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Is alternative splicing of apoptotic genes playing a role in the response to DNA or mitochondrial damage?

Yes, alternative splicing seem to play a key role in the response to DNA or mitocondrial damage as suggested by the number of apoptotic genes that are alternatively spliced, with often antagonistic roles of the isoforms generated.

Cancer chemotherapeutic agents such as cisplatin exert their cytotoxic effect by inducing DNA damage and activating programmed cell death (apoptosis). The tumour-suppressor protein p53 is an important activator of apoptosis. Although p53-deficient cancer cells are less responsive to chemotherapy, their resistance is not complete, which suggests that other apoptotic pathways may exist. A p53-related gene, p73, which encodes several proteins as a result of alternative splicing, can also induce apoptosis. Here we show that the amount of p73 protein in the cell is increased by cisplatin. This induction of p73 is not seen in cells unable to carry out mismatch repair and in which the nuclear enzyme c-Abl tyrosine kinase is not activated by cisplatin. The half-life of p73 is prolonged by cisplatin and by co-expression with c-Abl tyrosine kinase; the apoptosis-inducing function of p73 is also enhanced by the c-Abl kinase. Mouse embryo fibroblasts deficient in mismatch repair or in c-Abl do not upregulate p73 and are more resistant to killing by cisplatin. Our results indicate that c-Abl and p73 are components of a mismatch-repair-dependent apoptosis pathway which contributes to cisplatin-induced cytotoxicity. Caspase family genes play a critical role in the initiation and execution of programmed cell death. Programmed cell death is an important contributor to neuronal loss following cerebral ischemia. We have performed a series of experiments to investigate the role of a specific caspase, caspase-2, in the development of delayed neuronal death following transient global ischemia in the rat. A rat ischemic brain cDNA library was screened, and two splice-variants of caspase-2 mRNA were identified, caspase-2S and caspase-2L, which were highly homologous with the sequences of human and mouse caspase-2S and caspase-2L genes, respectively. RT-PCR demonstrated an increase in expression of both caspase-2S and caspase-2L mRNA at 8, 24 and 72 h of reperfusion after global ischemia. The ratio of the two PCR fragments did not change significantly throughout the time course of reperfusion. Western blot with monoclonal antibody specific to the pro-apoptotic caspase-2L splice variant revealed an increase in procaspase-2 (51 kDa) protein from 4 to 72 h following ischemia compared with sham-operated controls. Furthermore, an approximately 30-kDa cleavage product appeared at 8 h and increased with increasing duration of reperfusion. Thus, caspase-2L is both translated and activated following transient global ischemia. Finally, intraventricular administration of the caspase-2-like inhibitor (VDVAD-FMK) 30 min before induction of ischemia decreased the number of CA1 neurons staining positively for DNA damage (Klenow-labeling assay) and increased the number of healthy-appearing CA1 neurons (cresyl violet) compared with vehicle-treated controls. Taken together, the data suggest that caspase-2 induction and activation are important mediators of delayed neuronal death following transient global ischemia. Alternative splicing is an important source of protein diversity, and is an established but not yet fully understood mechanism for gene regulation in higher eukaryotes. Its regulation is governed by a variety of mechanisms, including variation in the expression levels of splicing factors engaged in spliceosome formation. SRp55 is one of the most ubiquitous splicing factors and one that can be up-regulated by DNA damage in the absence of p53, and we had previously found that depletion of its activity increased resistance to DNA damage in p53-dependant manner. To assess its influence on the splicing patterns of genes involved in apoptosis, we performed splice-specific microarray analysis of cells treated with siRNA specific for this gene. This analysis, backed by RT-PCR verification, identified three genes, KSR1, ZAK and mda7/IL24, which are sensitive to SRp55 depletion. We also analyzed the splice patterns of apoptosis-related genes in p53-deficient U2OS cells following treatment with the genotoxic drug mitomycin C. This analysis revealed that DNA damage resulted in changes in splicing activity that modified the splicing pattern of Fas, a key pro-apoptotic, p53-inducible death receptor. Interestingly, this modification led to an enrichment of the anti-apoptotic soluble Fas isoform, and this secreted isoform was detected in the media surrounding cells subjected to DNA damage. These findings show that modulation of splicing activity in p53-deficient cells during the early response to sub-lethal DNA damage results in a change in the splicing of target genes, thus modifying the cellular response to genotoxic agents. The transcription factor E2F1 has a key function during S phase progression and apoptosis. It has been well-demonstrated that the apoptotic function of E2F1 involves its ability to transactivate pro-apoptotic target genes. Alternative splicing of pre-mRNAs also has an important function in the regulation of apoptosis. In this study, we identify the splicing factor SC35, a member of the Ser-Rich Arg (SR) proteins family, as a new transcriptional target of E2F1. We demonstrate that E2F1 requires SC35 to switch the alternative splicing profile of various apoptotic genes such as c-flip, caspases-8 and -9 and Bcl-x, towards the expression of pro-apoptotic splice variants. Finally, we provide evidence that E2F1 upregulates SC35 in response to DNA-damaging agents and show that SC35 is required for apoptosis in response to these drugs. Taken together, these results demonstrate that E2F1 controls pre-mRNA processing events to induce apoptosis and identify the SC35 SR protein as a key direct E2F1-target in this setting. BRCA1 is a tumor suppressor gene that is mutated in families with breast and ovarian cancer. Several BRCA1 splice variants are found in different tissues, but their subcellular localization and functions are poorly understood at the moment. We previously described BRCA1 splice variant BRCA1a to induce apoptosis and function as a tumor suppressor of triple negative breast, ovarian and prostate cancers. In this study we have analyzed the function of BRCA1 isoforms (BRCA1a and BRCA1b) and compared them to the wild-type BRCA1 protein using several criteria like studying expression in normal and tumor cells by RNase protection assays, subcellular localization/fractionation by immunofluorescence microscopy and Western blot analysis, transcription regulation of biological relevant proteins and growth suppression in breast cancer cells. We are demonstrating for the first time that ectopically expressed GFP-tagged BRCA1, BRCA1a, and BRCA1b proteins are localized to the mitochondria, repress ELK-1 transcriptional activity and possess antiproliferative activity on breast cancer cells. These results suggest that the exon 9, 10, and 11 sequences (aa 263-1365) which contain two nuclear localization signals, p53, Rb, c-Myc, gamma-tubulin, Stat, Rad51, Rad50 binding domains, angiopoietin-1 repression domain are not absolutely required for mitochondrial localization and growth suppressor function of these proteins. Since mitochondrial dysfunction is a hallmark of cancer, we can speculate that the mitochondrial localization of BRCA1 proteins may be functionally significant in regulating both the mitochondrial DNA damage as well as apoptotic activity of BRCA1 proteins and mislocalization causes cancer. J. Cell. Physiol. 219: 634-641, 2009. (c) 2009 Wiley-Liss, Inc. DNA damage induces apoptosis and many apoptotic genes are regulated via alternative splicing (AS), but little is known about the control mechanisms. Here we show that ultraviolet irradiation (UV) affects cotranscriptional AS in a p53-independent way, through the hyperphosphorylation of RNA polymerase II carboxy-terminal domain (CTD) and a subsequent inhibition of transcriptional elongation, estimated in vivo and in real time. Phosphomimetic CTD mutants not only display lower elongation but also duplicate the UV effect on AS. Consistently, nonphosphorylatable mutants prevent the UV effect. Apoptosis promoted by UV in cells lacking p53 is prevented when the change in AS of the apoptotic gene bcl-x is reverted, confirming the relevance of this mechanism. Splicing-sensitive microarrays revealed a significant overlap of the subsets of genes that have changed AS with UV and those that have reduced expression, suggesting that transcriptional coupling to AS is a key feature of the DNA-damage response. The CCAAT box is a DNA element present in the majority of human promoters, bound by the trimeric NF-Y, composed of NF-YA, NF-YB, and NF-YC subunits. We describe and characterize novel isoforms of one of the two histone-like subunits, NF-YC. The locus generates a minimum of four splicing products, mainly located within the Q-rich activation domain. The abundance of each isoform is cell-dependent; only one major NF-YC isoform is present in a given cell type. The 37- and 50-kDa isoforms are mutually exclusive, and preferential pairings with NF-YA isoforms possess different transcriptional activities, with specific combinations being more active on selected promoters. The transcriptional regulation of the NF-YC locus is also complex, and mRNAs arise from the two promoters P1 and P2. Transient transfections, chromatin immunoprecipitations, and reverse transcription-PCRs indicate that P1 has a robust housekeeping activity; P2 possesses a lower basal activity, but it is induced in response to DNA damage in a p53-dependent way. Alternative promoter usage directly affects NF-YC splicing, with the 50-kDa transcript being excluded from P2. Specific functional inactivation of the 37-kDa isoform affects the basal levels of G(1)/S blocking and pro-apoptotic genes but not G(2)/M promoters. In summary, our data highlight an unexpected degree of complexity and regulation of the NF-YC gene, demonstrating the existence of a discrete cohort of NF-Y trimer subtypes resulting from the functional diversification of Q-rich transactivating subunits and a specific role of the 37-kDa isoform in suppression of the DNA damage-response under growing conditions.

Which oncogenes are able to induce cellular senescence?

Cellular senescence can be induced through activation or inactivation of a number of oncogenes, such as Ras, c-Abl, Raf, Myc, Skp2, BRAF, AKT, HDAC2, p38 MAPK, Caveolin-1 and Mek1.

Oncogenic activation of the mitogen-activated protein (MAP) kinase cascade in murine fibroblasts initiates a senescence-like cell cycle arrest that depends on the ARF/p53 tumor suppressor pathway. To investigate whether p53 is sufficient to induce senescence, we introduced a conditional murine p53 allele (p53(val135)) into p53-null mouse embryonic fibroblasts and examined cell proliferation and senescence in cells expressing p53, oncogenic Ras, or both gene products. Conditional p53 activation efficiently induced a reversible cell cycle arrest but was unable to induce features of senescence. In contrast, coexpression of oncogenic ras or activated mek1 with p53 enhanced both p53 levels and activity relative to that observed for p53 alone and produced an irreversible cell cycle arrest that displayed features of cellular senescence. p19(ARF) was required for this effect, since p53(-/-) ARF(-/-) double-null cells were unable to undergo senescence following coexpression of oncogenic Ras and p53. Although the levels of exogenous p53 achieved in ARF-null cells were relatively low, the stabilizing effects of p19(ARF) on p53 could not explain the cooperation between oncogenic Ras and p53 in promoting senescence. Hence, enforced p53 expression without oncogenic ras in p53(-/-) mdm2(-/-) double-null cells produced extremely high p53 levels but did not induce senescence. Taken together, our results indicate that oncogenic activation of the MAP kinase pathway in murine fibroblasts converts p53 into a senescence inducer through both quantitative and qualitative mechanisms. Caveolae are vesicular invaginations of the plasma membrane. Caveolin-1 is the principal structural component of caveolae in vivo. Several lines of evidence are consistent with the idea that caveolin-1 functions as a "transformation suppressor" protein. In fact, caveolin-1 mRNA and protein expression are lost or reduced during cell transformation by activated oncogenes. Interestingly, the human caveolin-1 gene is localized to a suspected tumor suppressor locus (7q31.1). We have previously demonstrated that overexpression of caveolin-1 arrests mouse embryonic fibroblasts in the G(0)/G(1) phase of the cell cycle through activation of a p53/p21-dependent pathway, indicating a role of caveolin-1 in mediating growth arrest. However, it remains unknown whether overexpression of caveolin-1 promotes cellular senescence in vivo. Here, we demonstrate that mouse embryonic fibroblasts transgenically overexpressing caveolin-1 show: 1) a reduced proliferative lifespan; 2) senescence-like cell morphology; and 3) a senescence-associated increase in beta-galactosidase activity. These results indicate for the first time that the expression of caveolin-1 in vivo is sufficient to promote and maintain the senescent phenotype. Subcytotoxic oxidative stress is known to induce premature senescence in diploid fibroblasts. Interestingly, we show that subcytotoxic level of hydrogen peroxide induces premature senescence in NIH 3T3 cells and increases endogenous caveolin-1 expression. Importantly, quercetin and vitamin E, two antioxidant agents, successfully prevent the premature senescent phenotype and the up-regulation of caveolin-1 induced by hydrogen peroxide. Also, we demonstrate that hydrogen peroxide alone, but not in combination with quercetin, stimulates the caveolin-1 promoter activity. Interestingly, premature senescence induced by hydrogen peroxide is greatly reduced in NIH 3T3 cells harboring antisense caveolin-1. Importantly, induction of premature senescence is recovered when caveolin-1 levels are restored. Taken together, these results clearly indicate a central role for caveolin-1 in promoting cellular senescence and they suggest the hypothesis that premature senescence may represent a tumor suppressor function mediated by caveolin-1 in vivo. MYC overexpression is thought to initiate tumorigenesis by inducing cellular proliferation and growth and to be restrained from causing tumorigenesis by inducing cell cycle arrest, cellular senescence, and/or apoptosis. Here we show that MYC can induce DNA breaks both in vitro and in vivo independent of increased production of reactive oxygen species (ROS). We provide an insight into the specific circumstances under which MYC generates ROS in vitro and propose a possible mechanism. We found that MYC induces DNA double-strand breaks (DSBs) independent of ROS production in murine lymphocytes in vivo as well as in normal human foreskin fibroblasts (NHFs) in vitro in normal (10%) serum, as measured by gammaH2AX staining. However, NHFs cultured in vitro in low serum (0.05%) and/or ambient oxygen saturation resulted in ROS-associated oxidative damage and DNA single-strand breaks (SSBs), as measured by Ape-1 staining. In NHFs cultured in low versus normal serum, MYC induced increased expression of CYP2C9, a gene product well known to be associated with ROS production. Specific inhibition of CYP2C9 by small interfering RNA was shown to partially inhibit MYC-induced ROS production. Hence, MYC overexpression can induce ROS and SSBs under some conditions, but generally induces widespread DSBs in vivo and in vitro independent of ROS production. Cellular senescence is generally defined as an irreversible state of G1 cell cycle arrest in which cells are refractory to growth factor stimulation. Cellular senescence can be induced through several different mechanisms. Primary mammalian cells display a finite life span, suggesting a mechanism that counts cell divisions. Those cells initially proliferate but eventually enter a state of permanent growth arrest, called replicative senescence. Erosion of telomeric DNA has emerged as a key factor in replicative senescence, which is antagonized during cell immortalization. Nevertheless, besides telomere shortening, there are other mechanisms inducing a growth arrest similar to the replicative senescencent phenotype. Oncogenic or mitogenic signals as well as DNA damage can induce such a phenotype of cellular senescence. All forms of cellular senescence share common signaling pathways and morphological features. Thereby, p53 seems to be essential for the senescence response. Many of these senescence inducing mechanisms can be experimentally recapitulated by the introduction of defined genetic elements. Replicative senescence due to telomere shortening can, for example, be induced by a domit negative version of telomerase, premature senescence by the overexpression of oncogenic ras, or p16. Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and maligcy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA-damaging chemotherapy. In cultured premaligt epithelial cells, SASPs induced an epithelial-mesenchyme transition and invasiveness, hallmarks of maligcy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promaligt paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment. Cellular senescence is characterized by an irreversible cell cycle arrest that, when bypassed by mutation, contributes to cellular immortalization. Activated oncogenes induce a hyperproliferative response, which might be one of the senescence cues. We have found that expression of such an oncogene, Akt, causes senescence in primary mouse hepatoblasts in vitro. Additionally, AKT-driven tumors undergo senescence in vivo following p53 reactivation and show signs of differentiation. In another in vivo system, i.e., liver fibrosis, hyperproliferative signaling through AKT might be a driving force of the senescence in activated hepatic stellate cells. Senescent cells up-regulate and secrete molecules that, on the one hand, can reinforce the arrest and, on the other hand, can signal to an innate immune system to clear the senescent cells. The mechanisms governing senescence and immortalization are overlapping with those regulating self-renewal and differentiation. These respective control mechanisms, or their disregulation, are involved in multiple pathological conditions including fibrosis, wound healing, and cancer. Understanding extracellular cues that regulate these processes may enable new therapies for these conditions. Activated oncogenes induce compensatory tumour-suppressive responses, such as cellular senescence or apoptosis, but the signals determining the main outcome remain to be fully understood. Here, we uncover a role for Cdk2 (cyclin-dependent kinase 2) in suppressing Myc-induced senescence. Short-term activation of Myc promoted cell-cycle progression in either wild-type or Cdk2 knockout mouse embryo fibroblasts (MEFs). In the knockout MEFs, however, the initial hyper-proliferative response was followed by cellular senescence. Loss of Cdk2 also caused sensitization to Myc-induced senescence in pancreatic beta-cells or splenic B-cells in vivo, correlating with delayed lymphoma onset in the latter. Cdk2-/- MEFs also senesced upon ectopic Wnt signalling or, without an oncogene, upon oxygen-induced culture shock. Myc also causes senescence in cells lacking the DNA repair protein Wrn. However, unlike loss of Wrn, loss of Cdk2 did not enhance Myc-induced replication stress, implying that these proteins suppress senescence through different routes. In MEFs, Myc-induced senescence was genetically dependent on the ARF-p53-p21Cip1 and p16INK4a-pRb pathways, p21Cip1 and p16INK4a being selectively induced in Cdk2-/- cells. Thus, although redundant for cell-cycle progression and development, Cdk2 has a unique role in suppressing oncogene- and/or stress-induced senescence. Pharmacological inhibition of Cdk2 induced Myc-dependent senescence in various cell types, including a p53-null human cancer cell line. Our data warrant re-assessment of Cdk2 as a therapeutic target in Myc- or Wnt-driven tumours. Activated RAS/BRAF oncogenes induce cellular senescence as a tumor-suppressive barrier in early cancer development, at least in part, via an oncogene-evoked DNA damage response (DDR). In contrast, Myc activation-although producing a DDR as well-is known to primarily elicit an apoptotic countermeasure. Using the Emu-myc transgenic mouse lymphoma model, we show here in vivo that apoptotic lymphoma cells activate macrophages to secrete transforming growth factor beta (TGF-beta) as a critical non-cell-autonomous inducer of cellular senescence. Accordingly, neutralization of TGF-beta action, like genetic inactivation of the senescence-related histone methyltransferase Suv39h1, significantly accelerates Myc-driven tumor development via cancellation of cellular senescence. These findings, recapitulated in human aggressive B cell lymphomas, demonstrate that tumor-prompted stroma-derived signals may limit tumorigenesis by feedback senescence induction. Cellular senescence has been recently shown to have an important role in opposing tumour initiation and promotion. Senescence induced by oncogenes or by loss of tumour suppressor genes is thought to critically depend on induction of the p19(Arf)-p53 pathway. The Skp2 E3-ubiquitin ligase can act as a proto-oncogene and its aberrant overexpression is frequently observed in human cancers. Here we show that although Skp2 inactivation on its own does not induce cellular senescence, aberrant proto-oncogenic signals as well as inactivation of tumour suppressor genes do trigger a potent, tumour-suppressive senescence response in mice and cells devoid of Skp2. Notably, Skp2 inactivation and oncogenic-stress-driven senescence neither elicit activation of the p19(Arf)-p53 pathway nor DNA damage, but instead depend on Atf4, p27 and p21. We further demonstrate that genetic Skp2 inactivation evokes cellular senescence even in oncogenic conditions in which the p19(Arf)-p53 response is impaired, whereas a Skp2-SCF complex inhibitor can trigger cellular senescence in p53/Pten-deficient cells and tumour regression in preclinical studies. Our findings therefore provide proof-of-principle evidence that pharmacological inhibition of Skp2 may represent a general approach for cancer prevention and therapy. The suppression of oncogenic levels of MYC is sufficient to induce sustained tumor regression associated with proliferative arrest, differentiation, cellular senescence, and/or apoptosis, a phenomenon known as oncogene addiction. However, after prolonged inactivation of MYC in a conditional transgenic mouse model of Eμ-tTA/tetO-MYC T-cell acute lymphoblastic leukemia, some of the tumors recur, recapitulating what is frequently observed in human tumors in response to targeted therapies. Here we report that these recurring lymphomas express either transgenic or endogenous Myc, albeit in many cases at levels below those in the original tumor, suggesting that tumors continue to be addicted to MYC. Many of the recurring lymphomas (76%) harbored mutations in the tetracycline transactivator, resulting in expression of the MYC transgene even in the presence of doxycycline. Some of the remaining recurring tumors expressed high levels of endogenous Myc, which was associated with a genomic rearrangement of the endogenous Myc locus or activation of Notch1. By gene expression profiling, we confirmed that the primary and recurring tumors have highly similar transcriptomes. Importantly, shRNA-mediated suppression of the high levels of MYC in recurring tumors elicited both suppression of proliferation and increased apoptosis, confirming that these tumors remain oncogene addicted. These results suggest that tumors induced by MYC remain addicted to overexpression of this oncogene. Activated oncogenes induce premature cellular senescence, a permanent state of proliferative arrest in primary rodent and human fibroblasts. Recent studies suggest that generation of reactive oxygen species (ROS) is involved in oncogenic Ras-induced premature senescence. However, the signaling mechanism controlling this oxidant-mediated irreversible growth arrest is not fully understood. Here, we show that through the Ras/MEK pathway, Ras oncogene up-regulated the expression of superoxide-generating oxidases, Nox1 in rat REF52 cells and Nox4 in primary human lung TIG-3 cells, leading to an increase in intracellular level of ROS. Ablation of Nox1 and Nox4 by small interfering RNAs (siRNAs) blocked the RasV12 senescent phenotype including β-galactosidase activity, growth arrest and accumulation of tumor suppressors such as p53 and p16Ink4a. This suggests that Nox-generated ROS transduce senescence signals by activating the p53 and p16Ink4a pathway. Furthermore, Nox1 and Nox4 siRNAs inhibited both Ras-induced DNA damage response and p38MAPK activation, whereas overexpression of Nox1 and Nox4 alone was able to induce senescence. The involvement of Nox1 in Ras-induced senescence was also confirmed with embryonic fibroblasts derived from Nox1 knockout mice. Together, these findings suggest that Nox1- and Nox4-generated ROS play an important role in Ras-induced premature senescence, which may involve DNA damage response and p38MAPK signaling pathways.

What is HbVar?

HbVar (http://globin.cse.psu.edu) is a relational database of hemoglobin variants and thalassemia mutations. Extensive information is recorded for each variant and mutation, including a description of the variant and associated pathology, hematology, electrophoretic mobility, methods of isolation, stability information, ethnic occurrence, structure studies, functional studies, and references. The initial information was derived from books by Dr. Titus Huisman and colleagues [Huisman et al., 1996, 1997, 1998]. The current database is updated regularly with the addition of new data and corrections to previous data. Queries can be formulated based on fields in the database. Tables of common categories of variants, such as all those involving the alpha1-globin gene (HBA1) or all those that result in high oxygen affinity, are maintained by automated queries on the database. Users can formulate more precise queries, such as identifying "all beta-globin variants associated with instability and found in Scottish populations." This new database should be useful for clinical diagnosis as well as in fundamental studies of hemoglobin biochemistry, globin gene regulation, and human sequence variation at these loci.

We have constructed a relational database of hemoglobin variants and thalassemia mutations, called HbVar, which can be accessed on the web at http://globin.cse.psu.edu. Extensive information is recorded for each variant and mutation, including a description of the variant and associated pathology, hematology, electrophoretic mobility, methods of isolation, stability information, ethnic occurrence, structure studies, functional studies, and references. The initial information was derived from books by Dr. Titus Huisman and colleagues [Huisman et al., 1996, 1997, 1998]. The current database is updated regularly with the addition of new data and corrections to previous data. Queries can be formulated based on fields in the database. Tables of common categories of variants, such as all those involving the alpha1-globin gene (HBA1) or all those that result in high oxygen affinity, are maintained by automated queries on the database. Users can formulate more precise queries, such as identifying "all beta-globin variants associated with instability and found in Scottish populations." This new database should be useful for clinical diagnosis as well as in fundamental studies of hemoglobin biochemistry, globin gene regulation, and human sequence variation at these loci. HbVar (http://globin.cse.psu.edu/globin/hbvar/) is a relational database developed by a multi-center academic effort to provide up-to-date and high quality information on the genomic sequence changes leading to hemoglobin variants and all types of thalassemia and hemoglobinopathies. Extensive information is recorded for each variant and mutation, including sequence alterations, biochemical and hematological effects, associated pathology, ethnic occurrence and references. In addition to the regular updates to entries, we report two significant advances: (i) The frequencies for a large number of mutations causing beta-thalassemia in at-risk populations have been extracted from the published literature and made available for the user to query upon. (ii) HbVar has been linked with the GALA (Genome Alignment and Annotation database, available at http://globin.cse.psu.edu/gala/) so that users can combine information on hemoglobin variants and thalassemia mutations with a wide spectrum of genomic data. It also expands the capacity to view and analyze the data, using tools within GALA and the University of California at Santa Cruz (UCSC) Genome Browser. HbVar (http://globin.bx.psu.edu/hbvar) is a locus-specific database (LSDB) developed in 2001 by a multi-center academic effort to provide timely information on the genomic sequence changes leading to hemoglobin variants and all types of thalassemia and hemoglobinopathies. Database records include extensive phenotypic descriptions, biochemical and hematological effects, associated pathology, and ethnic occurrence, accompanied by mutation frequencies and references. In addition to the regular updates to entries, we report significant advances and updates, which can be useful not only for HbVar users but also for other LSDB development and curation in general. The query page provides more functionality but in a simpler, more user-friendly format and known single nucleotide polymorphisms in the human alpha- and beta-globin loci are provided automatically. Population-specific beta-thalassemia mutation frequencies for 31 population groups have been added and/or modified and the previously reported delta- and alpha-thalassemia mutation frequency data from 10 population groups have also been incorporated. In addition, an independent flat-file database, named XPRbase (http://www.goldenhelix.org/xprbase), has been developed and linked to the main HbVar web page to provide a succinct listing of 51 experimental protocols available for globin gene mutation screening. These updates significantly augment the database profile and quality of information provided, which should increase the already high impact of the HbVar database, while its combination with the UCSC powerful genome browser and the ITHANET web portal paves the way for drawing connections of clinical importance, that is from genome to function to phenotype. Professor Titus H.J. Huisman is best known for his work on hemoglobin (Hb) variants. To date, more than 1,000 Hb variants have been discovered and characterized, of which about one-third were discovered in Titus Huisman's laboratory at the Medical College of Georgia, Augusta, GA, USA. A registry of these Hb variants and other information, a legacy from Professor Huisman, is now available online, at HbVar database (hhtp://globin.bx.psu.edu/hbvar). During the last century, major developments in Hb research have been made using physical, chemical, physiological and genetic methods. This review highlights the milestones and key developments in Hb research most relevant to hematologists, and that have impacted our understanding and management of the thalassemias and sickle cell disease. HbVar (http://globin.bx.psu.edu/hbvar) is one of the oldest and most appreciated locus-specific databases launched in 2001 by a multi-center academic effort to provide timely information on the genomic alterations leading to hemoglobin variants and all types of thalassemia and hemoglobinopathies. Database records include extensive phenotypic descriptions, biochemical and hematological effects, associated pathology and ethnic occurrence, accompanied by mutation frequencies and references. Here, we report updates to >600 HbVar entries, inclusion of population-specific data for 28 populations and 27 ethnic groups for α-, and β-thalassemias and additional querying options in the HbVar query page. HbVar content was also inter-connected with two other established genetic databases, namely FINDbase (http://www.findbase.org) and Leiden Open-Access Variation database (http://www.lovd.nl), which allows comparative data querying and analysis. HbVar data content has contributed to the realization of two collaborative projects to identify genomic variants that lie on different globin paralogs. Most importantly, HbVar data content has contributed to demonstrate the microattribution concept in practice. These updates significantly enriched the database content and querying potential, enhanced the database profile and data quality and broadened the inter-relation of HbVar with other databases, which should increase the already high impact of this resource to the globin and genetic database community.

Can DMSO as an additive improve proteomic analysis results?

Quantitative precisions improved significantly when DMSO (dimethylsulfoxide) was added to the matrix solution. Introducing to the 80% formic acid injection solution an organic solvent such as acetonitrile or acetonitrile-DMSO induced further retention selectivity, and increasing levels of organic solvents reduced on-column retention. Low percentages of dimethylsulfoxide (DMSO) in liquid chromatography solvents lead to a strong enhancement of electrospray ionization of peptides, improving the sensitivity of protein identification in bottom-up proteomics by up to tenfold.

In this report we explore the use of MALDI-FTICR mass spectrometry for the quantitative analysis of five HIV-1 protease inhibitors in cell lysates. 2,5-Dihydroxybenzoic acid (DHB) was used as the matrix. From a quantitative perspective, DHB is usually a poor matrix due to its poor shot-to-shot and poor spot-to-spot reproducibilities. We found that the quantitative precisions improved significantly when DMSO (dimethylsulfoxide) was added to the matrix solution. For lopinavir and ritonavir, currently the most frequently prescribed HIV-1 protease inhibitors, the signal-to-noise ratios improved significantly when potassium iodide was added to the matrix solution. The mean quantitative precisions, expressed as % relative standard deviation, were 6.4% for saquinavir, 7.3% for lopinavir, 8.5% for ritonavir, 11.1% for indinavir, and 7.2% for nelfinavir. The mean quantitative accuracies, expressed as % deviation, were 4.5% for saquinavir, 6.0% for lopinavir, 5.9% for ritonavir, 6.6% for indinavir, and 8.0% for nelfinavir. The concentrations measured for the individual quality control samples were all within 85-117% of the theoretical concentrations. The lower limits of quantification in cell lysates were 4 fmol/microL for saquinavir, 16 fmol/microL for lopinavir, 31 fmol/microL for ritonavir, and 100 fmol/microL for indinavir and nelfinavir. The mean mass accuracies for the protease inhibitors were 0.28 ppm using external calibration. Our results show that MALDI-FTICR mass spectrometry can be successfully used for precise, accurate, and selective quantitative analyses of HIV-1 protease inhibitors in cell lysates. In addition, the lower limits of quantification obtained allow clinical applications of the technique. In an effort to optimize reverse-phase liquid chromatography (RPLC) for proteomics, we studied the impact of composition of the sample injection solution on protein on-column selection and retention. All the proteins studied were retained on-column when injections were made in 50% formic acid, 0.1% TFA or 8.3M urea. When formic acid was increased to 80%, the superoxide dismutase standard (MW 26,159) and 58 mouse microsomal proteins that possessed low-range molecular weights, high pIs or basic amino acid clusters were non-retained, resulting in retention selectivity during sample injection. Introducing to the 80% formic acid injection solution an organic solvent such as acetonitrile or acetonitrile-DMSO induced further retention selectivity, and increasing levels of organic solvents reduced on-column retention. The proteome was split into the proteins that were retained on-column which eluted at higher retention times (RTs), vs the proteins that collected in the injection flow-through which normally eluted at lower RTs. This protein selectivity was confirmed after fraction collection, 1D-GE and o-LC-MS/MS. The significance of this procedure is that it can be exploited for fast extraction of small basic proteins from the bulk of the proteome and for on-column enrichment of hydrophobic proteins.

The antibodies MK-3475 and CT-011 have shown promising results in treating malignancies. Which protein are they targeting?

Modulation of the immune system by targeting coinhibitory and costimulatory receptors has become a promising new approach of immunotherapy for cancer. OBJECTIVE: CT-011 is a humanized IgG1 monoclonal antibody that modulates the immune response through interaction with PD-1, a protein belonging to the B7 receptor family present on lymphocytes. The objectives of this phase I study were to assess the dose-limiting toxicities, to determine the maximum tolerated dose, and to study the pharmacokinetics of CT-011 administered once to patients with advanced hematologic malignancies. We have developed a cancer vaccine in which autologous tumor is fused with dendritic cells resulting in the presentation of tumor antigens in the context of DC-mediated costimulation. The median t1/2 of CT-011 ranged from 217 to 410 hours. The PD1/PDL1 pathway is an important element contributing to tumor-mediated immune suppression. The recent approval of the CTLA-4-blocking antibody ipilimumab for the treatment of melanoma was a watershed event, opening up a new era in the field of immunotherapy. T-cell expression of programmed death receptor-1 down-regulates the immune response against malignancy by interacting with cognate ligands ( eg, PD-L1 ) on tumor cells; however, little is known regarding PD-1 and natural killer ( NK ) cells.

PURPOSE: CT-011 is a humanized IgG1 monoclonal antibody that modulates the immune response through interaction with PD-1, a protein belonging to the B7 receptor family present on lymphocytes. The objectives of this phase I study were to assess the dose-limiting toxicities, to determine the maximum tolerated dose, and to study the pharmacokinetics of CT-011 administered once to patients with advanced hematologic maligcies. EXPERIMENTAL DESIGN: Seventeen patients were treated with escalating doses of CT-011 ranging from 0.2 to 6 mg/kg. For pharmacokinetic analysis, blood samples were withdrawn from the patients before and immediately after treatment and at 24 hours, 48 hours, and on days 7, 14, and 21. CT-011 blood levels were assessed with a specific ELISA and derived concentrations were used to calculate pharmacokinetic parameters. Activation of the immune system was assessed by measuring peripheral blood CD4+, CD8+, and CD69+ lymphocytes. RESULTS: The study showed the antibody to be safe and well tolerated in this patient population. No single maximum tolerated dose was defined in this study. Clinical benefit was observed in 33% of the patients with one complete remission. Pharmacokinetic analyses show that serum Cmax and the AUC of CT-011 increased proportionally with dose. The median t1/2 of CT-011 ranged from 217 to 410 hours. Sustained elevation in the percentage of peripheral blood CD4+ lymphocytes was observed up to 21 days following CT-011 treatment. CONCLUSIONS: A single administration of 0.2 to 6.0 mg/kg of CT-011 is safe and well tolerated in patients with advanced hematologic maligcies. T-cell expression of programmed death receptor-1 (PD-1) down-regulates the immune response against maligcy by interacting with cognate ligands (eg, PD-L1) on tumor cells; however, little is known regarding PD-1 and natural killer (NK) cells. NK cells exert cytotoxicity against multiple myeloma (MM), an effect enhanced through novel therapies. We show that NK cells from MM patients express PD-1 whereas normal NK cells do not and confirm PD-L1 on primary MM cells. Engagement of PD-1 with PD-L1 should down-modulate the NK-cell versus MM effect. We demonstrate that CT-011, a novel anti-PD-1 antibody, enhances human NK-cell function against autologous, primary MM cells, seemingly through effects on NK-cell trafficking, immune complex formation with MM cells, and cytotoxicity specifically toward PD-L1(+) MM tumor cells but not normal cells. We show that lenalidomide down-regulates PD-L1 on primary MM cells and may augment CT-011's enhancement of NK-cell function against MM. We demonstrate a role for the PD-1/PD-L1 signaling axis in the NK-cell immune response against MM and a role for CT-011 in enhancing the NK-cell versus MM effect. A phase 2 clinical trial of CT-011 in combination with lenalidomide for patients with MM should be considered. We have developed a cancer vaccine in which autologous tumor is fused with dendritic cells (DCs) resulting in the presentation of tumor antigens in the context of DC-mediated costimulation. In clinical trials, immunologic responses have been observed, however responses may be muted by inhibitory pathways. The PD1/PDL1 pathway is an important element contributing to tumor-mediated immune suppression. In this study, we demonstrate that myeloma cells and DC/tumor fusions strongly express PD-L1. Compared with a control population of normal volunteers, increased PD-1 expression was observed on T cells isolated from patients with myeloma. It is interesting to note that after autologous transplantation, T-cell expression of PD-1 returned to levels seen in normal controls. We examined the effect of PD-1 blockade on T-cell response to DC/tumor fusions ex vivo. Presence of CT-011, an anti-PD1 antibody, promoted the vaccine-induced T-cell polarization towards an activated phenotype expressing Th1 compared with Th2 cytokines. A concomitant decrease in regulatory T cells and enhanced killing in a cytotoxicity assay was observed. In summary, we demonstrate that PD-1 expression is increased in T cells of patients with active myeloma, and that CT-011 enhances activated T-cell responses after DC/tumor fusion stimulation. Programmed death-1 receptor (PD-1) is expressed on T cells following TCR activation. Binding of this receptor to its cognate ligands, programmed death ligand (PDL)-1 and PDL-2, down-regulates signals by the TCR, promoting T-cell anergy and apoptosis, thus leading to immune suppression. Here, we find that using an anti-PD-1 antibody (CT-011) with Treg-cell depletion by low-dose cyclophosphamide (CPM), combined with a tumor vaccine, induces synergistic antigen-specific immune responses and reveals novel activities of each agent in this combination. This strategy led to complete regression of established tumors in a significant percentage of treated animals, with survival prolongation. We show for the first time that combining CT-011 and CPM significantly increases the number of vaccine-induced tumor-infiltrating CD8(+) T cells, with simultaneous decrease in infiltrating Treg cells. Interestingly, we find that CT-011 prolongs Treg-cell inhibition induced by CPM, leading to a sustainable significant synergistic decrease of splenic and tumor-infiltrated Treg cells. Surprisingly, we find that the anti-tumor effect elicited by the combination of CT-011 and CPM is dependent on both CD8(+) and CD4(+) T-cell responses, although the antigen we used is a class I MHC-restricted peptide. Thus, we describe a novel and effective therapeutic approach by combining multiple strategies to target several tumor-mediated immune inhibitory mechanisms. Programmed death 1 (PD-1) is a T cell co-inhibitory receptor with two ligands, PD-L1 and PD-L2. In cancer, this pathway plays a major role in immune resistance in the tumor environment. Blockade of this pathway can enhance antitumor immune responses. This review discusses the preclinical rationale for PD-1 pathway inhibition in advanced renal cell carcinoma and prostate cancer, in addition to the clinical activity and toxicity of the anti-PD-L1 antibody BMS-936559, as well as anti-PD-1 antibodies MK-3475 and BMS-936558.

Which are the different proteins/isoforms encoded but the ASPH (aspartate beta-hydroxylase) gene in humans?

Alternative splicing of the locus AbetaH-J-J (asparetyl-beta-hydroxylase) generates three functionally distinct proteins: an enzyme, AbetaH (aspartyl-beta-hydroxylase), a structural protein of the sarcoplasmic reticulum membrane (junctin), and an integral membrane calcium binding protein (junctate). Aspartyl (asparaginyl)-beta-hydroxylase (AAH), has also two related transcripts, Humbug and Junctin, which lack catalytic domains. The smallest BAH-related transcript (2,789 base pairs) uses an alternative 3' terminal exon, resulting in a protein lacking a catalytic domain. Evolutionary conservation of this noncatalytic isoform of BAH (humbug) is demonstrated in mouse, man, and Drosophila. A human junctin isoform (isoform 1, 225 aa) was also identified and characterized. The isoform 1 has a 15 aa insertion at the amino acid residue 55 of the human junctin.

The mouse aspartyl beta-hydroxylase gene (Asph, BAH) has been cloned and characterized. The mouse BAH gene spans 200 kilobase pairs of genomic DNA and contains 24 exons. Of three major BAH-related transcripts, the two largest (6,629 and 4,419 base pairs) encode full-length protein and differ only in the use of alternative polyadenylation signals. The smallest BAH-related transcript (2,789 base pairs) uses an alternative 3' terminal exon, resulting in a protein lacking a catalytic domain. Evolutionary conservation of this noncatalytic isoform of BAH (humbug) is demonstrated in mouse, man, and Drosophila. Monoclonal antibody reagents were generated, epitope-mapped, and used to definitively correlate RNA bands on Northern blots with protein species on Western blots. The gene for mouse junctin, a calsequestrin-binding protein, was cloned and characterized and shown to be encoded from the same locus. When expressed in heart tissue, BAH/humbug preferably use the first exon and often the fourth exon of junctin while preserving the reading frame. Thus, three individual genes share common exons and open reading frames and use separate promoters to achieve differential expression, splicing, and function in a variety of tissues. This unusual form of exon sharing suggests that the functions of junctin, BAH, and humbug may be linked. Junctate is a newly identified integral ER/SR membrane calcium binding protein, which is an alternative splicing form of the same gene generating aspartyl beta-hydroxylase and junctin. Screening a mouse heart cDNA library using canine junctin cDNA as a probe yielded three complete mouse heart cDNAs. One of the cDNAs is homologous to the previously reported human junctate. The three mouse junctate proteins are composed of 270, 259, and 215 amino acids (we named them junctate-1, -2, and -3). The apparent molecular masses of the mouse junctates in SDS-PAGE were in the range between 40 and 53 kDa. Northern and Western blot analyses indicate that mouse junctates are expressed in heart, brain, spleen, lung, liver, kidney, and stomach, but not in skeletal muscle. The apparent molecular weights of junctates from heart and brain were somewhat different from those from the other tissues tested, suggesting that there are tissue-specific expression patterns of the different junctate isoforms. Immunohistochemical studies showed that junctates were expressed both in ventricular and atrial tissues. This is the first study that shows the presence of 3 distinct cardiac junctate isoforms expressed in various mammalian tissues. Alternative splicing of the locus AbetaH-J-J generates three functionally distinct proteins: an enzyme, AbetaH (aspartyl-beta-hydroxylase), a structural protein of the sarcoplasmic reticulum membrane (junctin), and an integral membrane calcium binding protein (junctate). Junctin and junctate are two important proteins involved in calcium regulation in eukaryotic cells. To understand the regulation of these two proteins, we identified and functionally characterized one of the two promoter sequences of the AbetaH-J-J locus. We demonstrate that the P2 promoter of the AbetaH-J-J locus contains (i) a minimal sequence localized within a region -159 bp from the transcription initiation site, which is sufficient to activate transcription of both mRNAs; (ii) sequences which bind known transcriptional factors such as those belonging to the myocyte enhancer factor 2 (MEF-2), MEF-3, and NF-kappaB protein families; and (iii) sequences bound by unknown proteins. The functional characterization of the minimal promoter in C2C12 cells and in the rat soleus muscle in vivo model indicates the existence of cis elements having positive and negative effects on transcription. In addition, our data demonstrate that in striated muscle cells the calcium-dependent transcription factor MEF-2 is crucial for the transcription activity directed by the P2 promoter. The transcription directed by the AbetaH-J-J P2 promoter is induced by high expression of MEF-2, further stimulated by calcineurin and Ca2+/calmodulin-dependent protein kinase I, and inhibited by histone deacetylase 4. The human AbetaH-J-J locus is a genomic sequence which generates three functionally distinct proteins, the enzyme aspartyl-beta-hydroxylase (AbetaH), the structural protein of sarcoplasmic reticulum junctin, and the membrane-bound calcium binding protein junctate. The first and second exons are mutually exclusive when mature mRNAs are produced. Moreover, the use of different splice donors has been shown to be involved in the generation of protein diversity by alternative splicing. As to transcriptional regulation, two promoters (P1 and P2) were identified. When the P1 and P2 promoter sequences are compared, important differences are clearly detectable. The most interesting result emerging from studies focused on the P2 promoter is that the calcium-dependent transcriptional factor MEF-2 activates the transcription of junctin, junctate, and AbetaH in excitable tissues and, to a lesser extent, in kidney. No Sp1 binding sites are present in the P2 promoter. In contrast, P1 promoter contains GC-rich sequences, which have homologies with the Sp1 consensus binding site. The single genomic locus, AbetaH-J-J, encodes three functionally distinct proteins aspartyl beta-hydroxylase, junctin and junctate by alternative splicing. Among these three proteins, junctin and junctate could play important roles in the regulation of intracellular Ca(2+) by regulating either Ca(2+) release from intracellular Ca(2+) stores or Ca(2+) influx in various biological processes. Here we review recent findings concerning the expressional regulations and the proposed functions of junctin and junctate.

List processes which are under the control of the YAP protein.

Yes-associated protein (YAP), a transcription coactivator, is the major downstream effector of the Hippo pathway, which plays a critical role in organ size control, cell poliferation and cancer development and tissue homeostasis and differentiation.

Protein geranylgeranylation (GGylation) is an important biochemical process for many cellular signaling molecules. Previous studies have shown that GGylation is essential for cell survival in many types of cancer. However, the molecular mechanism mediating the cell survival effect remains elusive. In this report, we show that the Hippo pathway mediates GGylation-dependent cell proliferation and migration in breast cancer cells. Blockade of GGylation enhanced phosphorylation of Mst1/2 and Lats1, and inhibited YAP and TAZ activity and the Hippo-YAP/TAZ pathway-dependent transcription. The effect of GGylation blockade on inhibition of breast cancer cell proliferation and migration is dependent on the Hippo-YAP/TAZ signaling, in which YAP appears to regulate cell proliferation and TAZ to regulate cell migration. Furthermore, GGylation-dependent cell proliferation is correlated with the activity of YAP/TAZ in breast cancer cells. Finally, Gγ and RhoA are the GGylated proteins that may transduce GGylation signals to the Hippo-YAP/TAZ pathway. Taken together, our studies have demonstrated that the Hippo-YAP/TAZ pathway is essential for GGylation-dependent cancer cell proliferation and migration. The Hippo pathway is an important organ size control signaling network and the major regulatory mechanism of cell-contact inhibition. Yes associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) are its targets and terminal effectors: inhibition of the pathway promotes YAP/TAZ translocation to the nucleus, where they interact with transcriptional enhancer associate domain (TEAD) transcription factors and coactivate the expression of target genes, promoting cell proliferation. Defects in the pathway can result in overgrowth phenotypes due to deregulation of stem-cell proliferation and apoptosis; members of the pathway are directly involved in cancer development. The pharmacological regulation of the pathway might be useful in cancer prevention, treatment, and regenerative medicine applications; currently, a few compounds can selectively modulate the pathway. In this review, we present an overview of the Hippo pathway, the sequence and structural analysis of YAP/TAZ, the known pharmacological modulators of the pathway, especially those targeting YAP/TAZ-TEAD interaction. Yes-associated protein (YAP), a transcription coactivator, is the major downstream effector of the Hippo pathway, which plays a critical role in organ size control and cancer development. However, how YAP is regulated by extracellular stimuli in tumorigenesis remains incompletely understood. Netrin-1, a laminin-related secreted protein, displays proto-oncogenic activity in cancers. Nonetheless, the downstream signaling mediating its oncogenic effects is not well defined. Here we show that netrin-1 via its transmembrane receptors, deleted in colorectal cancer and uncoordinated-5 homolog, up-regulates YAP expression, escalating YAP levels in the nucleus and promoting cancer cell proliferation and migration. Inactivating netrin-1, deleted in colorectal cancer, or uncoordinated-5 homolog B (UNC5B) decreases YAP protein levels, abrogating cancer cell progression by netrin-1, whereas knockdown of mammalian STE20-like protein kinase 1/2 (MST1/2) or large tumor suppressor kinase 1/2 (Lats1/2), two sets of upstream core kinases of the Hippo pathway, has no effect in blocking netrin-1-induced up-regulation of YAP. Netrin-1 stimulates phosphatase 1A to dephosphorylate YAP, which leads to decreased ubiquitination and degradation, enhancing YAP accumulation and signaling. Hence, our findings support that netrin-1 exerts oncogenic activity through YAP signaling, providing a mechanism coupling extracellular signals to the nuclear YAP oncogene. YAP (Yes-associated protein) and TAZ (transcriptional coactivator with PDZ-binding motif) are major downstream effectors of the Hippo pathway that influences tissue homeostasis, organ size, and cancer development. Aberrant hyperactivation of YAP/TAZ causes tissue overgrowth and tumorigenesis, whereas their inactivation impairs tissue development and regeneration. Dynamic and precise control of YAP/TAZ activity is thus important to ensure proper physiological regulation and homeostasis of the cells. Here, we show that YAP/TAZ activation results in activation of their negative regulators, LATS1/2 (large tumor suppressor 1/2) kinases, to constitute a negative feedback loop of the Hippo pathway in both cultured cells and mouse tissues. YAP/TAZ in complex with the transcription factor TEAD (TEA domain family member) directly induce LATS2 expression. Furthermore, YAP/TAZ also stimulate the kinase activity of LATS1/2 through inducing NF2 (neurofibromin 2). This feedback regulation is responsible for the transient activation of YAP upon lysophosphatidic acid (LPA) stimulation and the inhibition of YAP-induced cell migration. Thus, this LATS-mediated feedback loop provides an efficient mechanism to establish the robustness and homeostasis of YAP/TAZ regulation. The Hippo signaling pathway converges on YAP to regulate growth, differentiation, and regeneration. Previous studies with overexpressed proteins have shown that YAP is phosphorylated by its upstream kinase, Lats1/2, on multiple sites, including an evolutionarily conserved 14-3-3-binding site whose phosphorylation is believed to inhibit YAP by excluding it from the nucleus. Indeed, nuclear localization of YAP or decreased YAP phosphorylation at this site (S168 in Drosophila, S127 in humans, and S112 in mice) is widely used in current literature as a surrogate of YAP activation even though the physiological importance of this phosphorylation event in regulating endogenous YAP activity has not been defined. Here we address this question by introducing a Yap(S112A) knock-in mutation in the endogenous Yap locus. The Yap(S112A) mice are surprisingly normal despite nuclear localization of the mutant YAP protein in vivo and profound defects in cytoplasmic translocation in vitro. Interestingly, the mutant Yap(S112A) mice show a compensatory decrease in YAP protein levels due to increased phosphorylation at a mammalian-specific phosphodegron site on YAP. These findings reveal a robust homeostatic mechanism that maintains physiological levels of YAP activity and caution against the assumptive use of YAP localization alone as a surrogate of YAP activity. BACKGROUND: The inactivation of the Hippo pathway lead to TAZ (PDZ-binding motif)/YAP (yes-associated protein) overexpression, and is associated with worse prognostic outcomes in various cancers including hepatocellular carcinoma (HCC). Although there are several reports of microRNA (miR) targeting for YAP, miR targeting for TAZ remains unclear. The aim of this study is to identify the miR targeting TAZ expression in HCC. METHODS: MicroRNA expression was analysed using the Human miFinder 384HC miScript miR PCR array, and was compared between low and high TAZ expression cell lines. Then, we extracted miR-9-3p as a tumour-suppressor miR targeting TAZ. We examined the functional role of miR-9-3p using miR-9-3p mimic and inhibitor in HCC cell lines). RESULTS: In HCC cell lines and HCC clinical samples, there was the inverse correlation between miR-9-3p and TAZ expressions. TAZ expression was induced by treatment of miR-9-3p inhibitor and was downregulated by treatment of miR-9-3p mimic. Treatment of miR-9-3p mimic inhibited cell proliferative ability with downregulated phosphorylations of Erk1/2, AKT, and β-catenin in HLF. Inversely, treatment of miR-9-3p inhibitor accelerated cell growth compared with control in HuH1. CONCLUSIONS: MicroRNA-9-3p was identified as the tumour-suppressor miR targetting TAZ expression in HCC cells. BACKGROUND: Ewing's sarcoma tumor is an aggressive maligcy of bone and soft tissue in children and young adults. Despite advances in modern therapy, metastasis occurs and results in high mortality. Intracellular molecules Yap, Akt, mTOR, and Erk are signaling pathway members that regulate the proliferation of tumor cells. OBJECTIVE AND METHODS: We studied the immunohistochemical expression of these proteins in 36 tumor samples from adult and pediatric patients with Ewing's sarcoma tumors. Patients' age, sex, tumor site, tumor size, clinical stage and survival (overall and disease-free survival) were collected. Tissue microarrays slides were stained with antibodies against Yap, Akt, mTOR, and Erk proteins. RESULTS: Tumors exhibited variable expression of Yap, Akt, mTOR, and Erk (from negative, low to high), with high levels of expression present in 31%, 53%, 77% and 0% respectively. Immunohistochemical expression of Akt was associated with worse overall and disease-free survival (p<0.05). The other biomarkers did not demonstrate any difference in survival between low versus high expression. CONCLUSION: Although Yap, Akt, mTOR, and Erk protein are all expressed in Ewing's sarcoma by immunohistochemistry, only Akt expression is associated with worse prognosis. Larger studies are needed to verify these results and plan targeted therapy, particularly against Akt.

What family do mDia proteins belong in?

mDia proteins are members of the formin family.

OBJECTIVE: To compare communication in triadic (three-person) and dyadic (two-person) older patient medical interviews and to determine the influence of the presence of a third person on the physician-older patient relationship. DESIGN: Matched sample of dyadic and triadic audiotaped outpatient medical visits. Audiotapes were coded with the Multi-dimensional Interaction Analysis (MDIA) system. SETTING: Hospital-based medical primary care group practice in a major urban teaching institution. PARTICIPANTS: Patients 60 years and older who were making their first visit to study physicians. In a sample of 96 audiotaped initial medical visits, 15 encounters involved three persons. These 15 cases were matched with 15 dyadic interviews for gender and race of the patient and for gender and race of the physician. MAIN OUTCOME MEASURES: Content, interactional processes, and specific language and communication behaviors of older patients, physicians, and third persons in the medical encounter, as measured by the MDIA system. RESULTS: The specific content and the quality of interactional processes of physicians were not affected by the presence of a third person. However, older patients raised fewer topics in all content areas (medical, personal habits, psychosocial, and physician-patient relationship) in triads than in dyads. Overall, patients were less responsive (ie, the quality of their questioning, informing, and supportiveness was poorer) on patient-raised topics in triads than in dyads. Patients were rated as less assertive and expressive, and there was less joint decision-making and shared laughter in triads than in dyads. Patients were frequently excluded from conversations in visits in which a third person was present. CONCLUSIONS: The presence of a third person in the medical encounter changes the interactional dynamics of older patient medical interviews and may influence the development of a trusting and effective physician-older patient relationship. Rho, a member of the Rho small G protein family, regulates the formation of stress fibers and focal adhesions in various types of cultured cells. We investigated here the actions of ROCK and mDia, both of which have been identified to be putative downstream target molecules of Rho, in Madin-Darby canine kidney cells. The domit active mutant of RhoA induced the formation of parallel stress fibers and focal adhesions, whereas the domit active mutant of ROCK induced the formation of stellate stress fibers and focal adhesions, and the domit active mutant of mDia induced the weak formation of parallel stress fibers without affecting the formation of focal adhesions. In the presence of C3 ADP-ribosyltransferase for Rho, the domit active mutant of ROCK induced the formation of stellate stress fibers and focal adhesions, whereas the domit active mutant of mDia induced only the diffuse localization of actin filaments. These results indicate that ROCK and mDia show distinct actions in reorganization of the actin cytoskeleton. The domit negative mutant of either ROCK or mDia inhibited the formation of stress fibers and focal adhesions, indicating that both ROCK and mDia are necessary for the formation of stress fibers and focal adhesions. Moreover, inactivation and reactivation of both ROCK and mDia were necessary for the 12-O-tetradecanoylphorbol-13-acetate-induced disassembly and reassembly, respectively, of stress fibers and focal adhesions. The morphologies of stress fibers and focal adhesions in the cells expressing both the domit active mutants of ROCK and mDia were not identical to those induced by the domit active mutant of Rho. These results indicate that at least ROCK and mDia cooperatively act as downstream target molecules of Rho in the Rho-induced reorganization of the actin cytoskeleton. Rho is a member of the Ras-related family of small molecular weight GTP-binding proteins, and works as a molecular switch by shuttling between the GDP-bound inactive form and the GTP-bound active form. Cellular functions of Rho have been studied by two ways; one is to express or microinject constitutively active Rho mutants in cells to identify the active phenotype of Rho, and the other is to use botulinum C3 exoenzyme that specifically ADP-ribosylates and inactivates Rho in cells to find out phenotypes of Rho inactivation. These analyses have revealed that Rho is involved in cell to substratum adhesion and motility, cell contraction and cytokinesis through the reorganization of the actincytoskeleton and modulation of its activity. These actions of Rho are mediated by downstream Rho effectors. Several putative Rho effectors have been isolated on the basis of their selective binding to the GTP-bound form of Rho. Among them, the ROCK family of Rho-associated serine/threonine protein kinases inactivates cofilin and myosin phosphatase to induce stabilization of filamentous actin and increase in the actomyosin-based contractility. mDia binds profilin likely to promote actin polymerization. Thus, these effectors in combination are supposed to work in organization of various forms of the actin cytoskeleton. Furthermore, analyses using a ROCK specific inhibitor Y-27632 have suggested that the Rho-ROCK pathway works in contractions of vascular and bronchial smooth muscles under various pathological conditions and is involved in maligt cell transformation and tumor invasion and metastasis. In migrating adherent cells such as fibroblasts and endothelial cells, the microtubule-organizing center (MTOC) reorients toward the leading edge [1-3]. MTOC reorientation repositions the Golgi toward the front of the cell [1] and contributes to directional migration [4]. The mechanism of MTOC reorientation and its relation to the formation of stabilized microtubules (MTs) in the leading edge, which occurs concomitantly with MTOC reorientation [3], is unknown. We show that serum and the serum lipid, lysophosphatidic acid (LPA), increased Cdc42 GTP levels and triggered MTOC reorientation in serum-starved wounded monolayers of 3T3 fibroblasts. Cdc42, but not Rho or Rac, was both sufficient and necessary for LPA-stimulated MTOC reorientation. MTOC reorientation was independent of Cdc42-induced changes in actin and was not blocked by cytochalasin D. Inhibition of dynein or dynactin blocked LPA- and Cdc42-stimulated MTOC reorientation. LPA also stimulates a Rho/mDia pathway that selectively stabilizes MTs in the leading edge [5, 6]; however, activators and inhibitors of MTOC reorientation and MT stabilization showed that each response was regulated independently. These results establish an LPA/Cdc42 signaling pathway that regulates MTOC reorientation in a dynein-dependent manner. MTOC reorientation and MT stabilization both act to polarize the MT array in migrating cells, yet these processes act independently and are regulated by separate Rho family GTPase-signaling pathways. Rho is a member of the Ras-related family of small molecular weight GTP-binding proteins, and Rho works as a molecular switch by shuttling between the GDP-bound inactive form and the GTP-bound active form. Rho is involved in cell motility, cell adhesion, and cytokinesis through the reorganization of the actin cytoskeleton. In addition to this, Rho also regulates Ras-induced transformation, transcriptional activation and cell cycle progression. These actions through the Rho signaling are mediated by downstream Rho effectors. Several putative Rho effectors including ROCK and mDia have been isolated on the basis of their selective binding to the GTP-bound form of Rho. Among them, the ROCK family of Rho-associated serine/threonine protein kinases inactivates myosin phosphatase and actin depolymerizing factor (cofilin/Destrin) to induce stabilization of filamentous actin and increase in the actomyosin-based contractility. mDia binds profilin likely to promote actin polymerization. Thus, these effectors are supposed to work in organization of the actin cytoskeleton. Furthermore, analyses using a ROCK specific inhibitor Y-27632 have suggested that the Rho-ROCK pathway works in contractions of vascular smooth muscles and is involved in maligt cell transformation and tumor invasion and metastasis. Diaphanous related formins (DRFs) are part of the formin protein family that control morphogenesis, embryonic differentiation, cytokinesis, and cell polarity. DRFs organize the cytoskeleton in eukaryotic cells via the interaction with specific members of the Rho family of small GTPases including Rho, Rac, and Cdc42. This is best understood for Rho, which transmits signals to the actin cytoskeleton through the cooperation of its DRF effector mDia with ROCK (Rho-associated kinase). Here, we show that a constitutive active form of the Rac-interacting DRF FHOD1 (formin homology 2 domain containing 1) associates with F-actin in NIH3T3 cells, resulting in the formation of thick actin fibers. Cytoskeletal changes induced by FHOD1 correlated with the induction of serum response element transcription and were mediated by formin homology domains 1 and 2 of FHOD1. FHOD1-induced effects required the activity of the Rho-ROCK cascade that is targeted at a level downstream of Rho by the DRF. However, when the functional interaction of FHOD1 with individual GTPases was addressed, Rac but not Rho or Cdc42 bound to FHOD1 in cells and induced its recruitment to actin filaments and lamellipodia/membrane ruffles. Furthermore, activated FHOD1 interfered with lamellipodia formation. These results indicate that FHOD1 acts as an effector of Rac in actin rearrangements and transcriptional regulation and may provide a link for the Rac-dependent activation of the Rho cascade. Cell movement is driven by the coordinated regulation of cytoskeletal reorganization through Rho GTPases downstream of integrin and growth-factor receptor signaling. We have reported that mDia, a target protein of Rho, interacts with Src and DIP. Here we show that DIP binds to p190RhoGAP and Vav2, and that DIP is phosphorylated by Src and mediates the phosphorylation of p190RhoGAP and Vav2 upon EGF stimulation. When endogenous DIP was inhibited by expressing domit-negative mutants of DIP or siRNA, phosphorylation of p190RhoGAP and Vav2 upon EGF stimulation was diminished, and EGF-induced actin organization, distribution of p190RhoGAP and Vav2, and cell movement were affected. Therefore, DIP seems to transfer the complex of the three proteins from cytosol to beneath the membrane, and the three proteins, in turn, can be phosphorylated by Src. DIP inactivated Rho and activated Rac following EGF stimulation in the membrane fraction. Thus, DIP acts as a regulatory molecule causing Src kinase-dependent feedback modulation of Rho GTPases downstream of Rho-mDia upon EGF stimulation, and plays an important role in cell motility. Cell shape-dependent control of cell-cycle progression underlies the spatial differentials of growth that drive tissue morphogenesis, yet little is known about how cell distortion impacts the biochemical signaling machinery that is responsible for growth control. Here we show that the Rho family GTPase, RhoA, conveys the "cell shape signal" to the cell-cycle machinery in human capillary endothelial cells. Cells accumulating p27(kip1) and arrested in mid G(1) phase when spreading were inhibited by restricted extracellular matrix adhesion, whereas constitutively active RhoA increased expression of the F-box protein Skp2 required for ubiquitination-dependent degradation of p27(kip1) and restored G(1) progression in these cells. Studies with domit-negative and constitutively active forms of mDia1, a downstream effector of RhoA, and with a pharmacological inhibitor of ROCK, another RhoA target, revealed that RhoA promoted G(1) progression by altering the balance of activities between these two downstream effectors. These data indicate that signaling proteins such as mDia1 and ROCK, which are thought to be involved primarily in cytoskeletal remodeling, also mediate cell growth regulation by coupling cell shape to the cell-cycle machinery at the level of signal transduction. Formin proteins regulate the actin and microtubule cytoskeletons and also control the activity of the SRF transcription factor through depletion of the G-actin pool. Although the conserved formin homology 2 (FH2) domains of the mDia1 and Bni1 formins can nucleate actin polymerization in vitro, the activity of other FH2 domains and the relationship between actin polymerization and microtubule reorganization have been controversial. We show that, similar to the mDia1 FH2 domain, the FH2 domains of mDia2 and ld are sufficient for SRF activation in vivo. We demonstrate that an mDia1 mutant defective for microtubule rearrangement in vivo is also defective in SRF activation in vivo as well as actin polymerization in vitro and that the mDia2 FH2 domain promotes actin polymerization in vitro. Using co-immunoprecipitation, we show that mDia1 is oligomeric in its inactive autoinhibited state in vivo, that the active mDia1 and mDia2 FH2 domains form homo- but not hetero-oligomers in vivo, and that oligomerization is abolished by inactivating FH2 deletion and point mutations. Nevertheless, inactive mDia1 FH2 domain mutants retain the ability to interfere with cellular mDia activity. Our results show that self-oligomerization is essential for SRF activation in vivo and F-actin assembly in vitro and provide strong support for recent structural models of the FH2 domain. Macrophages, dendritic cells, and neutrophils use phagocytosis to capture and clear off invading pathogens. The process is triggered by the interaction of ligands on the pathogens' surface with specific phagocytic receptors, including immunoglobulin (FcR) and complement C3bi (CR3) receptors (integrin alpha(M)beta2, Mac1) . Localized actin-filament assembly that acts as the driving force for particle engulfment is controlled by Rho-family small GTPases . RhoA regulates CR3-mediated phagocytosis through a mechanism that is still unclear . Mammalian Diaphanous-related (mDia) formins participate in the generation of a diverse set of actin-remodeling events downstream of RhoA , and mDia1 is recruited around fibronectin-coated beads in a RhoA-dependent manner in fibroblasts . Here, we set out to examine whether mDia proteins are involved in CR3-mediated phagocytosis in macrophages. We show that the RhoA effector mDia1 is recruited early during CR3-mediated phagocytosis and colocalizes with polymerized actin in the phagocytic cup. Interfering with mDia activity inhibits CR3-mediated phagocytosis while having no effect on FcR-mediated phagocytosis. These results indicate a new function for mDia proteins in the regulation of actin polymerization during CR3-mediated phagocytosis. Rho GTPases and the dynamic assembly and disassembly of actin filaments have been shown to have critical roles in both the internalization and trafficking of growth factor receptors. While all three mammalian Diaphanous-related (mDia1/2/3) formin GTPase effector proteins have been localized on endosomes, a role for their actin nucleation, filament elongation, and/or bundling remains poorly understood in the context of intracellular trafficking. In a study of a functional relationship between RhoB, a GTPase known to associate with both early- and late-endosomes, and the formin mDia2, we show that 1) RhoB and mDia2 interact on endosomes; 2) GTPase activity-the ability to hydrolyze GTP to GDP-is required for the ability of RhoB to govern endosome dynamics; and 3) the actin dynamics controlled by RhoB and mDia2 is necessary for vesicle trafficking. These studies further suggest that Rho GTPases significantly influence the activity of mDia family formins in driving cellular membrane remodeling through the regulation of actin dynamics. Rho GTPases and their downstream effectors regulate changes in the actin cytoskeleton that underlie cell motility and adhesion. They also participate, with RhoA, in the regulation of gene transcription by activating serum response factor (SRF)-mediated transcription from the serum response element (SRE). SRF-mediated transcription is also promoted by several proteins that regulate the polymerization or stability of actin. We have previously identified a family of PP2C phosphatases, POPXs, which can dephosphorylate the CDC42/RAC-activated kinase PAK and downregulate its enzymatic and actin cytoskeletal activity. We now report that POPX2 interacts with the formin protein mDia1 (DIAPH1). This interaction is enhanced when mDia1 is activated by RhoA. The binding of POPX2 to mDia1 or to an mDia-containing complex greatly decreases the ability of mDia1 to activate transcription from the SRE. We propose that the interaction between mDia1 and POPX2 (PPM1F) serves to regulate both the actin cytoskeleton and SRF-mediated transcription, and to link the CDC42/RAC1 pathways with those of RhoA. Formin-family proteins, in the active state, form actin-based structures such as stress fibres. Their activation mechanisms, however, are largely unknown except that mDia and its closely related formins can be activated by direct binding of the small GTPase Rho or Cdc42. Here we show that the Rho-dependent protein kinase ROCK phosphorylates the C-terminal residues Ser1131, Ser1137, and Thr1141 of formin homology domain protein 1 (FHOD1), a major endothelial formin that is normally autoinhibited by intramolecular interaction between the N- and C-terminal regions. Phosphorylation of FHOD1 at the three residues fully disrupts the autoinhibitory interaction, which culminates in formation of stress fibres. We also demonstrate that, in vascular endothelial cells, thrombin, a vasoactive substance leading to Rho activation, elicits both FHOD1 phosphorylation and stress fibre formation in a ROCK-dependent manner, and that FHOD1 depletion by RNA interference impairs thrombin-induced stress fibre formation. Based on these findings we propose a novel mechanism for activation of formin-family proteins: ROCK, activated by G protein-coupled receptor ligands such as thrombin, directly phosphorylates FHOD1 at the C-terminal region, which renders this formin in the active form, leading to stress fibre formation. mDia proteins are mammalian homologues of Drosophila diaphanous and belong to the formin family proteins that catalyze actin nucleation and polymerization. Although formin family proteins of nonmammalian species such as Drosophila diaphanous are essential in cytokinesis, whether and how mDia proteins function in cytokinesis remain unknown. Here we depleted each of the three mDia isoforms in NIH 3T3 cells by RNA interference and examined this issue. Depletion of mDia2 selectively increased the number of binucleate cells, which was corrected by coexpression of RNAi-resistant full-length mDia2. mDia2 accumulates in the cleavage furrow during anaphase to telophase, and concentrates in the midbody at the end of cytokinesis. Depletion of mDia2 induced contraction at aberrant sites of dividing cells, where contractile ring components such as RhoA, myosin, anillin, and phosphorylated ERM accumulated. Treatment with blebbistatin suppressed abnormal contraction, corrected localization of the above components, and revealed that the amount of F-actin at the equatorial region during anaphase/telophase was significantly decreased with mDia2 RNAi. These results demonstrate that mDia2 is essential in mammalian cell cytokinesis and that mDia2-induced F-actin forms a scaffold for the contractile ring and maintains its position in the middle of a dividing cell. We examined the role of the actin nucleation promoters neural Wiskott-Aldrich syndrome protein (N-WASP) and WAVE2 in cell protrusion in response to epidermal growth factor (EGF), a key regulator in carcinoma cell invasion. We found that WAVE2 knockdown (KD) suppresses lamellipod formation and increases filopod formation, whereas N-WASP KD has no effect. However, simultaneous KD of both proteins results in the formation of large jagged protrusions with lamellar properties and increased filopod formation. This suggests that another actin nucleation activity is at work in carcinoma cells in response to EGF. A mammalian Diaphanous-related formin, mDia1, localizes at the jagged protrusions in double KD cells. Constitutively active mDia1 recapitulated the phenotype, whereas inhibition of mDia1 blocked the formation of these protrusions. Increased RhoA activity, which stimulates mDia1 nucleation, was observed in the N-WASP/WAVE2 KD cells and was shown to be required for the N-WASP/WAVE2 KD phenotype. These data show that coordinate regulation between the WASP family and mDia proteins controls the balance between lamellar and lamellipodial protrusion activity. The Rho subgroup of the Rho GTPases consisting of RhoA, RhoB and RhoC induces a specific type of actin cytoskeleton and carry out a variety of functions in the cell. mDia and ROCK are downstream effectors of Rho mediating Rho action on the actin cytoskeleton; mDia produces actin filaments by nucleation and polymerization and ROCK activate myosin to cross-link them for induction of actomyosin bundles and contractility. mDia is potentially linked to Rac activation and membrane ruffle formation through c-Src-induced phosphorylation of focal adhesion proteins, and ROCK antagonizes this mDia action. Thus, cell morphogenesis, adhesion, and motility can be determined by the balance between mDia and ROCK activities. Though they are not oncogenes by themselves, overexpression of RhoA and RhoC are often found in clinical cancers, and RhoC has been repeatedly identified as a gene associated with metastasis. The Rho-ROCK pathway is implicated in Ras-mediated transformation, the amoeboid movement of tumor cells in the three-dimensional matrix, and transmigration of tumor cells through the mesothelial monolayer. On the other hand, the Rho-mDia1 pathway is implicated in Src-mediated remodeling of focal adhesions and migration of tumor cells. There is also an indication that the Rho pathway other than ROCK is involved in Src-mediated induction of podosome and regulation of matrix metalloproteases. Thus, Rho mediates various phenotypes of maligt transformation by Ras and Src through its effectors, ROCK and mDia. Mouse Diaphanous-related formins (mDias) are members of the formin protein family that nucleate actin polymerization and subsequently promote filamentous actin (F-actin) elongation by monomer addition to fast-growing barbed ends. It has been suggested that mDias preferentially recruit actin complexed to profilin due to their proline-rich FH1 domains. During filament elongation, dimeric mDias remain attached to the barbed ends by their FH2 domains, which form an anti-parallel ring-like structure enclosing the filament barbed ends. Dimer formation of mDia-FH2 domains is dependent on their N-terminal lasso and linker subdomains (connector). Here, we investigated the effect of isolated FH2 domains on actin polymerization using mDia1-FH2 domain plus connector, as well as core mDia1, mDia2, and mDia3 missing the connector, by cosedimentation and electron microscopy after negative staining. Analytical ultracentrifugation showed that core FH2 domains of mDia1 and mDia2 exhibited a low degree of dimer formation, whereas mDia3-FH2 minus connector and mDia1-FH2 plus connector readily dimerized. Only core mDia3-FH2 was able to nucleate actin polymerization. However, all tested core FH2 domains decorated and bundled F-actin, as demonstrated by electron microscopy after negative staining. Bundling activity was highest for mDia3-FH2, decreased for mDia2-FH2, and further decreased for mDia1-FH2. The mDia1-FH2 domain plus connector induced actin polymerization also in the absence of profilin, but failed to induce F-actin deformation and bundling. We also tested whether mDia1-FH2 was able to repolymerize actin in complex with different proteins that stabilize globular actin. The data obtained demonstrated that mDia1-FH2 induced actin repolymerization only from the actin/cofilin-1 complex, but not when complexed to actin depolymerizing factor, gelsolin segment 1, vitamin D binding protein, or deoxyribonuclease I. Inverted formin 2 (INF2) encodes a member of the diaphanous subfamily of formin proteins. Mutations in INF2 cause human kidney disease characterized by focal and segmental glomerulosclerosis. Disease-causing mutations occur only in the diaphanous inhibitory domain (DID), suggesting specific roles for this domain in the pathogenesis of disease. In a yeast two-hybrid screen, we identified the diaphanous autoregulatory domains (DADs) of the mammalian diaphanous-related formins (mDias) mDia1, mDia2, and mDia 3 as INF2_DID-interacting partners. The mDias are Rho family effectors that regulate actin dynamics. We confirmed in vitro INF2_DID/mDia_DAD binding by biochemical assays, confirmed the in vivo interaction of these protein domains by coimmunoprecipitation, and observed colocalization of INF2 and mDias in glomerular podocytes. We investigated the influence of this INF2_DID/mDia_DAD interaction on mDia mediated actin polymerization and on serum response factor (SRF) activation. We find that the interaction of INF2_DID with mDia_DAD inhibited mDia-mediated, Rho-activated actin polymerization, as well as SRF-responsive gene transcriptional changes. Similar assays using the disease-causing E184K and R218Q mutations in INF2_DID showed a decreased effect on SRF activation and gene transcription. The binding of INF2_DID to mDia_DAD may serve as a negative regulatory mechanism for mDias' function in actin-dependent cell processes. The effects of disease-causing INF2 mutations suggest an important role for this protein and its interaction with other formins in modulating glomerular podocyte phenotype and function. The single-celled human parasite Entamoeba histolytica possesses a dynamic actin cytoskeleton vital for its intestinal and systemic pathogenicity. The E. histolytica genome encodes several Rho family GTPases known to regulate cytoskeletal dynamics. EhRho1, the first family member identified, was reported to be insensitive to the Rho GTPase-specific Clostridium botulinum C3 exoenzyme, raising the possibility that it may be a misclassified Ras family member. Here, we report the crystal structures of EhRho1 in both active and inactive states. EhRho1 is activated by a conserved switch mechanism, but diverges from mammalian Rho GTPases in lacking a signature Rho insert helix. EhRho1 engages a homolog of mDia, EhFormin1, suggesting a role in mediating serum-stimulated actin reorganization and microtubule formation during mitosis. EhRho1, but not a constitutively active mutant, interacts with a newly identified EhRhoGDI in a prenylation-dependent manner. Furthermore, constitutively active EhRho1 induces actin stress fiber formation in mammalian fibroblasts, thereby identifying it as a functional Rho family GTPase. EhRho1 exhibits a fast rate of nucleotide exchange relative to mammalian Rho GTPases due to a distinctive switch one isoleucine residue reminiscent of the constitutively active F28L mutation in human Cdc42, which for the latter protein, is sufficient for cellular transformation. Nonconserved, nucleotide-interacting residues within EhRho1, revealed by the crystal structure models, were observed to contribute a moderating influence on fast spontaneous nucleotide exchange. Collectively, these observations indicate that EhRho1 is a bona fide member of the Rho GTPase family, albeit with unique structural and functional aspects compared with mammalian Rho GTPases. Filopodia are dynamic actin-rich cell surface protrusions involved in cell migration, axon guidance, and wound healing. The RhoGTPase Cdc42 generates filopodia via IRSp53, a multidomain protein that links the processes of plasma membrane deformation and actin dynamics required for their formation in mammalian cells. The Src homology 3 domain of IRSp53 binds to the actin regulators Mena, Eps8, WAVE1, WAVE2, mDia1, and mDia2. We show that mDia1 and WAVE2 synergize with IRSp53 to form filopodia. IRSp53 also interacts directly with these two proteins within filopodia, as observed in acceptor photobleaching FRET studies. Measurement of filopodium formation by time-lapse imaging of live cells also revealed that depleting neuronal cells of either mDia1 or WAVE2 protein decreases the ability of IRSp53 to induce filopodia. In contrast, IRSp53 does not appear to partner WAVE1 or mDia2 to give rise to these structures. In addition, although all three isoforms of mDia are capable of inducing filopodia, IRSp53 requires only mDia1 to do so. These findings suggest that mDia1 and WAVE2 are important Src homology 3 domain partners of IRSp53 in forming filopodia. Filopodia are dynamic, actin-rich finger-like structures that protrude from the cell membrane and play important roles in cell migration and neurite initiation and outgrowth. The insulin receptor substrate protein of 53 kDa (IRSp53) and the mammalian Diaphanous members of the formin family of proteins (mDia) are two key players in the formation of filopodia and neurites. IRSp53 is an adaptor protein that acts at the membrane:actin interface, coupling membrane deformation with F-actin polymerization. mDia formin proteins, instead, can nucleate and polymerize linear actin filaments. Emerging genetic and biochemical evidence indicate that there are multiple and independent pathways leading to filopodium and neurite formation, but the precise molecular components of these pathways remain ill-defined. We recently identified the PDZ domain-containing protein LIN7 as a novel regulator of IRSp53. We further showed that the association between these two proteins is required to promote the formation of filopodia and neurites independently from mDia formin proteins, highlighting novel mechanisms of filopodia and neurite formation. RhoA is one of the more extensively studied members of the Rho family of small GTPase where it is most readily recognized for its contributions to actin-myosin contractility and stress fiber formation. Accordingly, RhoA function during cell migration has been relegated to the rear of the cell where it mediates retraction of the trailing edge. However, RhoA can also mediate membrane ruffling, lamellae formation and membrane blebbing, thus suggesting an active role in membrane protrusions at the leading edge. With the advent of fluorescence resoce energy transfer (FRET)-based Rho activity reporters, RhoA has been shown to be active at the leading edge of migrating cells where it precedes Rac and Cdc42 activation. These observations demonstrate a remarkable versatility to RhoA signaling, but how RhoA function can switch between contraction and protrusion has remained an enigma. This review highlights recent advances regarding how the cooperation of Rho effector Rhotekin and S100A4 suppresses stress fiber generation to permit RhoA-mediated lamellae formation. The mammalian striatin family consists of three proteins, striatin, S/G2 nuclear autoantigen, and zinedin. Striatin family members have no intrinsic catalytic activity, but rather function as scaffolding proteins. Remarkably, they organize multiple diverse, large signaling complexes that participate in a variety of cellular processes. Moreover, they appear to be regulatory/targeting subunits for the major eukaryotic serine/threonine protein phosphatase 2A. In addition, striatin family members associate with germinal center kinase III kinases as well as other novel components, earning these assemblies the name striatin-interacting phosphatase and kinase (STRIPAK) complexes. Recently, there has been a great increase in functional and mechanistic studies aimed at identifying and understanding the roles of STRIPAK and STRIPAK-like complexes in cellular processes of multiple organisms. These studies have identified novel STRIPAK and STRIPAK-like complexes and have explored their roles in specific signaling pathways. Together, the results of these studies have sparked increased interest in striatin family complexes because they have revealed roles in signaling, cell cycle control, apoptosis, vesicular trafficking, Golgi assembly, cell polarity, cell migration, neural and vascular development, and cardiac function. Moreover, STRIPAK complexes have been connected to clinical conditions, including cardiac disease, diabetes, autism, and cerebral cavernous malformation. In this review, we discuss the expression, localization, and protein domain structure of striatin family members. Then we consider the diverse complexes these proteins and their homologs form in various organisms, emphasizing what is known regarding function and regulation. Finally, we explore possible roles of striatin family complexes in disease, especially cerebral cavernous malformation. The apical surface of secretory tubular epithelia is a dynamic cellular domain where massive membrane turnover takes place during exocytosis and its subsequent compensatory endocytosis. This extensive membrane flow poses a difficulty in targeting secretory vesicles efficiently to a narrow apical domain. We have studied how actin filaments mediate the secretory process in the murine exocrine pancreas, which produces and secretes digestive enzymes that are deposited into the intestine. We show that cargo-filled secretory vesicles move over bundles of linear actin cables from their storage areas to the apical membrane of pancreatic acinar cells. mDia1, a linear actin nucleator of the Formin family, was identified as the generator of these structures. The active form of mDia1 localizes to the apical surface, and the microfilament bundles it forms emanate from the apical surface and extend into the cytoplasm, generating polarized secretion tracks. These bundles ensure orderly progression of exocytosis, since the apical targeting of pancreatic vesicles is compromised in their absence, and vesicles fuse with each other to generate compound, membrane-associated secretory structures.

Is nucleosome eviction ATP-dependent?

Yes, nucleosome eviction and chromatin remodelling depends on ATP

ATP-dependent chromatin remodeling complexes play a critical role in chromatin dynamics. A large number of in vitro studies have pointed towards nucleosome sliding as the principal remodeling outcome of SWI/SNF action, whereas few have described histone octamer transfer as the principal outcome. In contrast, recent in vivo studies have linked the activity of SWI/SNF to histone eviction in trans from gene promoters. In this study, we have found that the chimeric transcription factor Gal4-VP16 can enhance SWI/SNF histone octamer transfer activity, resulting in targeted histone eviction from a nucleosome probe. This effect is dependent on the presence of the activation domain. We observed that under conditions mimicking the in vivo relative abundance of SWI/SNF with respect to the total number of nucleosomes in a cell nucleus, the accessibility of the transcription factor binding site is the first determit in the sequence of events leading to nucleosome remodeling. We propose a model mechanism for this transcription factor-mediated enhancement of SWI/SNF octamer transfer activity. ATP-dependent chromatin-remodeling complexes, such as RSC, can reposition, evict or restructure nucleosomes. A structure of a RSC-nucleosome complex with a nucleosome determined by cryo-EM shows the nucleosome bound in a central RSC cavity. Extensive interaction of RSC with histones and DNA seems to destabilize the nucleosome and lead to an overall ATP-independent rearrangement of its structure. Nucleosomal DNA appears disordered and largely free to bulge out into solution as required for remodeling, but the structure of the RSC-nucleosome complex indicates that RSC is unlikely to displace the octamer from the nucleosome to which it is bound. Consideration of the RSC-nucleosome structure and published biochemical information suggests that ATP-dependent DNA translocation by RSC may result in the eviction of histone octamers from adjacent nucleosomes. The histone chaperone Vps75 forms a complex with, and stimulates the activity of, the histone acetyltransferase Rtt109. However, Vps75 can also be isolated on its own and might therefore possess Rtt109-independent functions. Analysis of epistatic miniarray profiles showed that VPS75 genetically interacts with factors involved in transcription regulation whereas RTT109 clusters with genes linked to DNA replication/repair. Additional genetic and biochemical experiments revealed a close relationship between Vps75 and RNA polymerase II. Furthermore, Vps75 is recruited to activated genes in an Rtt109-independent manner, and its genome-wide association with genes correlates with transcription rate. Expression microarray analysis identified a number of genes whose normal expression depends on VPS75. Interestingly, histone H2B dynamics at some of these genes are consistent with a role for Vps75 in histone H2A/H2B eviction/deposition during transcription. Indeed, reconstitution of nucleosome disassembly using the ATP-dependent chromatin remodeler Rsc and Vps75 revealed that these proteins can cooperate to remove H2A/H2B dimers from nucleosomes. These results indicate a role for Vps75 in nucleosome dynamics during transcription, and importantly, this function appears to be largely independent of Rtt109. Ino80 is an ATP-dependent nucleosome-remodeling enzyme involved in transcription, replication, and the DNA damage response. Here, we characterize the fission yeast Ino80 and find that it is essential for cell viability. We show that the Ino80 complex from fission yeast mediates ATP-dependent nucleosome remodeling in vitro. The purification of the Ino80-associated complex identified a highly conserved complex and the presence of a novel zinc finger protein with similarities to the mammalian transcriptional regulator Yin Yang 1 (YY1) and other members of the GLI-Krüppel family of proteins. Deletion of this Iec1 protein or the Ino80 complex subunit arp8, ies6, or ies2 causes defects in DNA damage repair, the response to replication stress, and nucleotide metabolism. We show that Iec1 is important for the correct expression of genes involved in nucleotide metabolism, including the ribonucleotide reductase subunit cdc22 and phosphate- and adenine-responsive genes. We find that Ino80 is recruited to a large number of promoter regions on phosphate starvation, including those of phosphate- and adenine-responsive genes that depend on Iec1 for correct expression. Iec1 is required for the binding of Ino80 to target genes and subsequent histone loss at the promoter and throughout the body of these genes on phosphate starvation. This suggests that the Iec1-Ino80 complex promotes transcription through nucleosome eviction. The ATP-dependent chromatin remodeling complex SWI/SNF regulates transcription and has been implicated in promoter nucleosome eviction. Efficient nucleosome disassembly by SWI/SNF alone in biochemical assays, however, has not been directly observed. Employing a model system of dinucleosomes rather than mononucleosomes, we demonstrate that remodeling leads to ordered and efficient disassembly of one of the two nucleosomes. An H2A/H2B dimer is first rapidly displaced, and then, in a slower reaction, an entire histone octamer is lost. Nucleosome disassembly by SWI/SNF did not require additional factors such as chaperones or acceptors of histones. Observations in single molecules as well as bulk measurement suggest that a key intermediate in this process is one in which a nucleosome is moved toward the adjacent nucleosome. SWI/SNF recruited by the transcriptional activator Gal4-VP16 preferentially mobilizes the proximal nucleosome and destabilizes the adjacent nucleosome. The S. cerevisiae Rpd3 large (Rpd3L) and small (Rpd3S) histone deacetylase (HDAC) complexes are prototypes for understanding transcriptional repression in eukaryotes [1]. The current view is that they function by deacetylating chromatin, thereby limiting accessibility of transcriptional factors to the underlying DNA. However, an Rpd3 catalytic mutant retains substantial repression capability when targeted to a promoter as a LexA fusion protein [2]. We investigated the HDAC-independent properties of the Rpd3 complexes biochemically and discovered a chaperone function, which promotes histone deposition onto DNA, and a novel activity, which prevents nucleosome eviction but not remodeling mediated by the ATP-dependent RSC complex. These HDAC-independent activities inhibit Pol II transcription on a nucleosomal template. The functions of the endogenous Rpd3 complexes can be recapitulated with recombit Rpd3 core complex comprising Sin3, Rpd3, and Ume1. To test the hypothesis that Rpd3 contributes to chromatin stabilization in vivo, we measured histone H3 density genomewide and found that it was reduced at promoters in an Rpd3 deletion mutant but partially restored in a catalytic mutant. Importantly, the effects on H3 density are most apparent on RSC-enriched genes [3]. Our data suggest that the Rpd3 core complex could contribute to repression via a novel nucleosome stabilization function. Nucleosomes, the basic organizational units of chromatin, package and regulate eukaryotic genomes. ATP-dependent nucleosome-remodeling factors endow chromatin with structural flexibility by promoting assembly or disruption of nucleosomes and the exchange of histone variants. Furthermore, most remodeling factors induce nucleosome movements through sliding of histone octamers on DNA. We summarize recent progress toward unraveling the basic nucleosome sliding mechanism and the interplay of the remodelers' DNA translocases with accessory domains. Such domains optimize and regulate the basic sliding reaction and exploit sliding to achieve diverse structural effects, such as nucleosome positioning or eviction, or the regular spacing of nucleosomes in chromatin. We investigate how DNA sequence, ATP-dependent chromatin remodeling and nucleosome-depleted 'barriers' co-operate to determine the kinetics of nucleosome organization, in a stochastic model of nucleosome positioning and dynamics. We find that 'statistical' positioning of nucleosomes against 'barriers', hypothesized to control chromatin structure near transcription start sites, requires active remodeling and therefore cannot be described using equilibrium statistical mechanics. We show that, unlike steady-state occupancy, DNA site exposure kinetics near a barrier is dominated by DNA sequence rather than by proximity to the barrier itself. The timescale for formation of positioning patterns near barriers is proportional to the timescale for active nucleosome eviction. We also show that there are strong gene-to-gene variations in nucleosome positioning near barriers, which are eliminated by averaging over many genes. Our results suggest that measurement of nucleosome kinetics can reveal information about sequence-dependent regulation that is not apparent in steady-state nucleosome occupancy.

Is TREM2 associated with Alzheimer's disease in humans?

TREM2 variants have been found to be associated with early as well as with late onset Alzheimer's disease.

Triggering Receptor Expressed on Myeloid cells (TREM)2 deficiency originates a genetic syndrome characterized by bone cysts and presenile dementia, named Nasu-Hakola disease (NHD). Early onset dementia and marked involvement of frontal regions are features characterizing both NHD and other kinds of neurodegenerative disorders, such as Frontotemporal Lobar Degeneration (FTLD), and, in some cases, Alzheimer's disease (AD). Three Single Nucleotide Polymorphisms (SNPs) in TREM2 coding region were screened by allelic discrimination in a population of probable AD patients as well as FTLD patients as compared with age-matched controls. In addition, mutation scanning of the coding region of TREM2 gene was carried out in 7 patients with early onset AD (EOAD), 16 FTLD, and 20 controls. None of the SNPs analyzed was present, either in patients or controls. Moreover, mutation scanning of the five exons of TREM2 failed to detect the presence of novel polymorphisms. These data demonstrate that TREM2 coding region is highly conserved, implying a crucial role of this receptor. Further studies, including a functional analysis, are certainly required to clarify the role of TREM2 in neurodegenerative processes. BACKGROUND: Sequence variants, including the ε4 allele of apolipoprotein E, have been associated with the risk of the common late-onset form of Alzheimer's disease. Few rare variants affecting the risk of late-onset Alzheimer's disease have been found. METHODS: We obtained the genome sequences of 2261 Icelanders and identified sequence variants that were likely to affect protein function. We imputed these variants into the genomes of patients with Alzheimer's disease and control participants and then tested for an association with Alzheimer's disease. We performed replication tests using case-control series from the United States, Norway, The Netherlands, and Germany. We also tested for a genetic association with cognitive function in a population of unaffected elderly persons. RESULTS: A rare missense mutation (rs75932628-T) in the gene encoding the triggering receptor expressed on myeloid cells 2 (TREM2), which was predicted to result in an R47H substitution, was found to confer a significant risk of Alzheimer's disease in Iceland (odds ratio, 2.92; 95% confidence interval [CI], 2.09 to 4.09; P=3.42×10(-10)). The mutation had a frequency of 0.46% in controls 85 years of age or older. We observed the association in additional sample sets (odds ratio, 2.90; 95% CI, 2.16 to 3.91; P=2.1×10(-12) in combined discovery and replication samples). We also found that carriers of rs75932628-T between the ages of 80 and 100 years without Alzheimer's disease had poorer cognitive function than noncarriers (P=0.003). CONCLUSIONS: Our findings strongly implicate variant TREM2 in the pathogenesis of Alzheimer's disease. Given the reported antiinflammatory role of TREM2 in the brain, the R47H substitution may lead to an increased predisposition to Alzheimer's disease through impaired containment of inflammatory processes. (Funded by the National Institute on Aging and others.). BACKGROUND: Homozygous loss-of-function mutations in TREM2, encoding the triggering receptor expressed on myeloid cells 2 protein, have previously been associated with an autosomal recessive form of early-onset dementia. METHODS: We used genome, exome, and Sanger sequencing to analyze the genetic variability in TREM2 in a series of 1092 patients with Alzheimer's disease and 1107 controls (the discovery set). We then performed a meta-analysis on imputed data for the TREM2 variant rs75932628 (predicted to cause a R47H substitution) from three genomewide association studies of Alzheimer's disease and tested for the association of the variant with disease. We genotyped the R47H variant in an additional 1887 cases and 4061 controls. We then assayed the expression of TREM2 across different regions of the human brain and identified genes that are differentially expressed in a mouse model of Alzheimer's disease and in control mice. RESULTS: We found significantly more variants in exon 2 of TREM2 in patients with Alzheimer's disease than in controls in the discovery set (P=0.02). There were 22 variant alleles in 1092 patients with Alzheimer's disease and 5 variant alleles in 1107 controls (P<0.001). The most commonly associated variant, rs75932628 (encoding R47H), showed highly significant association with Alzheimer's disease (P<0.001). Meta-analysis of rs75932628 genotypes imputed from genomewide association studies confirmed this association (P=0.002), as did direct genotyping of an additional series of 1887 patients with Alzheimer's disease and 4061 controls (P<0.001). Trem2 expression differed between control mice and a mouse model of Alzheimer's disease. CONCLUSIONS: Heterozygous rare variants in TREM2 are associated with a significant increase in the risk of Alzheimer's disease. (Funded by Alzheimer's Research UK and others.). The rs75932628-T variant of the gene encoding the triggering receptor expressed on myeloid cells 2 (TREM2) has recently been identified as a rare risk factor for late-onset Alzheimer's disease (AD). In this study we examined the association between TREM2 exon 2 variants and early-onset AD in a sample of Caucasian subjects of French origin including 726 patients with age of onset ≤65 years and 783 controls. Only the rs75932628-T variant (predicted to cause an R47H substitution) conferred a significant risk for early-onset AD (OR, 4.07; 95% CI, 1.3 to 16.9; p = 0.009). These results confirm the association between this variant and AD and underline its involvement in early-onset cases. Two recent studies have reported the association of rs75932628-T in the TREM2 gene with the risk for Alzheimer's disease (AD). Rs75932628-T is a rare nonsynonymous variant (p.R47H) that confers a high risk of AD with an effect size similar to that of the APOE ɛ4 allele. However, this association has not been replicated in any independent studies to date. The allelic frequency of rs75932628 varies according to the population from 0.02% to 0.63% among healthy controls. In an attempt to replicate the association between rs75932628-T and AD risk, we genotyped rs75932628 in a cohort of 504 AD subjects and 550 healthy controls from a Spanish population. Rs75932628-T showed a minor allele frequency of 0.3% among this cohort. Interestingly, in our study, rs75932628-T was found exclusively in 1.4% of AD cases (7/504), including 4 early-onset AD cases, and in none of the controls (n = 0/550). Here, we report the first positive replication study in a Spanish population and confirm that TREM2 rs75932628-T is associated with the risk for AD. Recent works have demonstrated a rare functional variant (R47H) in triggering receptor expressed on myeloid cells (TREM) 2 gene, encoding TREM2 protein, increase susceptibility to late-onset Alzheimer's disease (AD), with an odds ratio similar to that of the apolipoprotein E ε4 allele. The reduced function of TREM2 was speculated to be the main cause in the pathogenic effects of this risk variant, and TREM2 is highly expressed in white matter, as well as in the hippocampus and neocortex, which is partly consistent with the pathological features reported in AD brain, indicating the possible involvement of TREM2 in AD pathogenesis. Emerging evidence has demonstrated that TREM2 could suppress inflammatory response by repression of microglia-mediated cytokine production and secretion, which may prevent inflammation-induced bystander damage of neurons. TREM2 also participates in the regulation of phagocytic pathways that are responsible for the removal of neuronal debris. In this article, we review the recent epidemiological findings of TREM2 that related with late-onset AD and speculate the possible roles of TREM2 in progression of this disease. Based on the potential protective actions of TREM2 in AD pathogenesis, targeting TREM2 might provide new opportunities for AD treatment. Genetic deficits and loss of function for the triggering receptor expressed in myeloid cells 2 (TREM2; encoded at chr6p21.1), a transmembrane spanning stimulatory receptor of the immunoglobulin/lectin-like gene superfamily, have been associated with deficiencies in phagocytosis and the innate immune system in Alzheimer's disease. In this study, we provide evidence that TREM2 is downregulated in samples of sporadic Alzheimer hippocampal CA1 compared with age-matched controls. A nuclear factor-кB (NF-кB)-sensitive miRNA-34a (encoded at chr1p36.22), upregulated in Alzheimer's disease, was found to target the 299 nucleotide human TREM2 mRNA 3'-untranslated region (3'-UTR) and downregulate the expression of a TREM2-3'-UTR reporter vector. A stabilized anti-miRNA-34a (AM-34a) quenched this pathogenic response. The results suggest that an epigenetic mechanism involving an NF-кB-mediated, miRNA-34a-regulated downregulation of TREM2 expression may shape innate immune and phagocytic responses that contribute to inflammatory neurodegeneration.

Which is the most common measure of differences between dinucleotide relative abundance "genomic signatures"

The concept of a genomic signature was introduced with the observation of species-type specific Dinucleotide Relative Abundance Profiles (DRAPs). The set of dinucleotide odds ratios or 'general design' is a remarkably stable property of the DNA of an organism, and can be used to discriminate between sequences from different organisms. The average absolute dinucleotide relative abundance difference is termed delta-distance. Delta-distance is the most commonly used measure of differences bwetween "genomic signatures". Delta-distances between different genomic sequences in the same species are low, and are generally smaller than the between-species delta-distances.

Early biochemical experiments established that the set of dinucleotide odds ratios or 'general design' is a remarkably stable property of the DNA of an organism, which is essentially the same in protein-coding DNA, bulk genomic DNA, and in different renaturation rate and density gradient fractions of genomic DNA in many organisms. Analysis of currently available genomic sequence data has extended these earlier results, showing that the general designs of disjoint samples of a genome are substantially more similar to each other than to those of sequences from other organisms and that closely related organisms have similar general designs. From this perspective, the set of dinucleotide odds ratio (relative abundance) values constitute a signature of each DNA genome, which can discriminate between sequences from different organisms. Dinucleotide-odds ratio values appear to reflect not only the chemistry of dinucleotide stacking energies and base-step conformational preferences, but also the species-specific properties of DNA modification, replication and repair mechanisms. Genomic homogeneity is investigated for a broad base of DNA sequences in terms of dinucleotide relative abundance distances (abbreviated delta-distances) and of oligonucleotide compositional extremes. It is shown that delta-distances between different genomic sequences in the same species are low, only about 2 or 3 times the distance found in random DNA, and are generally smaller than the between-species delta-distances. Extremes in short oligonucleotides include underrepresentation of TpA and overrepresentation of GpC in most temperate bacteriophage sequences; underrepresentation of CTAG in most eubacterial genomes; underrepresentation of GATC in most bacteriophage; CpG suppression in vertebrates, in all animal mitochondrial genomes, and in many thermophilic bacterial sequences; and overrepresentation of GpG/CpC in all animal mitochondrial sets and chloroplast genomes. Interpretations center on DNA structures (dinucleotide stacking energies, DNA curvature and superhelicity, nucleosome organization), context-dependent mutational events, methylation effects, and processes of replication and repair. We compare and contrast genome-wide compositional biases and distributions of short oligonucleotides across 15 diverse prokaryotes that have substantial genomic sequence collections. These include seven complete genomes (Escherichia coli, Haemophilus influenzae, Mycoplasma genitalium, Mycoplasma pneumoniae, Synechocystis sp. strain PCC6803, Methanococcus jannaschii, and Pyrobaculum aerophilum). A key observation concerns the constancy of the dinucleotide relative abundance profiles over multiple 50-kb disjoint contigs within the same genome. (The profile is rhoXY* = fXY*/fX*fY* for all XY, where fX* denotes the frequency of the nucleotide X and fY* denotes the frequency of the dinucleotide XY, both computed from the sequence concatenated with its inverted complementary sequence.) On the basis of this constancy, we refer to the collection [rhoXY*] as the genome signature. We establish that the differences between [rhoXY*] vectors of 50-kb sample contigs of different genomes virtually always exceed the differences between those of the same genomes. Various di- and tetranucleotide biases are identified. In particular, we find that the dinucleotide CpG=CG is underrepresented in many thermophiles (e.g., M. jannaschii, Sulfolobus sp., and M. thermoautotrophicum) but overrepresented in halobacteria. TA is broadly underrepresented in prokaryotes and eukaryotes, but normal counts appear in Sulfolobus and P. aerophilum sequences. More than for any other bacterial genome, palindromic tetranucleotides are underrepresented in H. influenzae. The M. jannaschii sequence is unprecedented in its extreme underrepresentation of CTAG tetranucleotides and in the anomalous distribution of CTAG sites around the genome. Comparative analysis of numbers of long tetranucleotide microsatellites distinguishes H. influenzae. Dinucleotide relative abundance differences between bacterial sequences are compared. For example, in these assessments of differences, the cyanobacteria Synechocystis, Synechococcus, and Anabaena do not form a coherent group and are as far from each other as general gram-negative sequences are from general gram-positive sequences. The difference of M. jannaschii from low-G+C gram-positive proteobacteria is one-half of the difference from gram-negative proteobacteria. Interpretations and hypotheses center on the role of the genome signature in highlighting similarities and dissimilarities across different classes of prokaryotic species, possible mechanisms underlying the genome signature, the form and level of genome compositional flux, the use of the genome signature as a chronometer of molecular phylogeny, and implications with respect to the three putative eubacterial, archaeal, and eukaryote domains of life and to the origin and early evolution of eukaryotes. We provide data and analysis to support the hypothesis that the ancestor of animal mitochondria (Mt) and many primitive amitochondrial (a-Mt) eukaryotes was a fusion microbe composed of a Clostridium-like eubacterium and a Sulfolobus-like archaebacterium. The analysis is based on several observations: (i) The genome signatures (dinucleotide relative abundance values) of Clostridium and Sulfolobus are compatible (sufficiently similar) and each has significantly more similarity in genome signatures with animal Mt sequences than do all other available prokaryotes. That stable fusions may require compatibility in genome signatures is suggested by the compatibility of plasmids and hosts. (ii) The expanded energy metabolism of the fusion organism was strongly selective for cementing such a fusion. (iii) The molecular apparatus of endospore formation in Clostridium serves as raw material for the development of the nucleus and cytoplasm of the eukaryotic cell. Plasmids are ubiquitous mobile elements that serve as a pool of many host beneficial traits such as antibiotic resistance in bacterial communities. To understand the importance of plasmids in horizontal gene transfer, we need to gain insight into the 'evolutionary history' of these plasmids, i.e. the range of hosts in which they have evolved. Since extensive data support the proposal that foreign DNA acquires the host's nucleotide composition during long-term residence, comparison of nucleotide composition of plasmids and chromosomes could shed light on a plasmid's evolutionary history. The average absolute dinucleotide relative abundance difference, termed delta-distance, has been commonly used to measure differences in dinucleotide composition, or 'genomic signature', between bacterial chromosomes and plasmids. Here, we introduce the Mahalanobis distance, which takes into account the variance-covariance structure of the chromosome signatures. We demonstrate that the Mahalanobis distance is better than the delta-distance at measuring genomic signature differences between plasmids and chromosomes of potential hosts. We illustrate the usefulness of this metric for proposing candidate long-term hosts for plasmids, focusing on the virulence plasmids pXO1 from Bacillus anthracis, and pO157 from Escherichia coli O157:H7, as well as the broad host range multi-drug resistance plasmid pB10 from an unknown host.

Name a method for enrichment of arginine-methylated peptides.

Immunoaffinity purification using specific antibodies has been used in order to perform enrichment of methylated peptides.

Protein methylation is a common posttranslational modification that mostly occurs on arginine and lysine residues. Arginine methylation has been reported to regulate RNA processing, gene transcription, DNA damage repair, protein translocation, and signal transduction. Lysine methylation is best known to regulate histone function and is involved in epigenetic regulation of gene transcription. To better study protein methylation, we have developed highly specific antibodies against monomethyl arginine; asymmetric dimethyl arginine; and monomethyl, dimethyl, and trimethyl lysine motifs. These antibodies were used to perform immunoaffinity purification of methyl peptides followed by LC-MS/MS analysis to identify and quantify arginine and lysine methylation sites in several model studies. Overall, we identified over 1000 arginine methylation sites in human cell line and mouse tissues, and ∼160 lysine methylation sites in human cell line HCT116. The number of methylation sites identified in this study exceeds those found in the literature to date. Detailed analysis of arginine-methylated proteins observed in mouse brain compared with those found in mouse embryo shows a tissue-specific distribution of arginine methylation, and extends the types of proteins that are known to be arginine methylated to include many new protein types. Many arginine-methylated proteins that we identified from the brain, including receptors, ion channels, transporters, and vesicle proteins, are involved in synaptic transmission, whereas the most abundant methylated proteins identified from mouse embryo are transcriptional regulators and RNA processing proteins.

Why do we use "N-terminal proteomics"?

N-terminal proteomics allows the systematic identification of protease/peptidase cleavage events revealing substrate cleavage specificities.

We present here a novel proteomics design for systematic identification of protease cleavage events by quantitative N-terminal proteomics, circumventing the need for time-consuming manual validation. We bypass the singleton detection problem of protease-generated neo-N-terminal peptides by introducing differential isotopic proteome labeling such that these substrate reporter peptides are readily distinguished from all other N-terminal peptides. Our approach was validated using the canonical human caspase-3 protease and further applied to mouse cathepsin D and E substrate processing in a mouse dendritic cell proteome, identifying the largest set of protein protease substrates ever reported and gaining novel insight into substrate specificity differences of these cathepsins. In this study, we performed the first large-scale identification of N-terminal peptides from the green sulfur bacterium Chlorobaculum tepidum. Combined fractional diagonal chromatography (COFRADIC) was used to isolate protein N-terminal peptides from three different proteome preparations, and following LC-MS/MS analysis, over 621 different proteins were identified by their N-terminal peptides. Our data constitute the largest data set currently available for protein N-termini of prokaryotic photosynthetic organisms. Protein N-terminal acetylation is one of the most common modifications occurring co- and post-translationally on either eukaryote or prokaryote proteins. However, compared to other protein modifications, the physiological role of protein N-terminal acetylation is relatively unclear. To explore the biological functions of protein N-terminal acetylation, a robust and large-scale method for qualitative and quantitative analysis of this modification is required. Enrichment of N(α)-acetylated peptides or depletion of the free N-terminal and internal tryptic peptides prior to analysis by mass spectrometry are necessary based on current technologies. This study demonstrated a simple strong cation exchange (SCX) fractionation method to selectively enrich N(α)-acetylated tryptic peptides via dimethyl labeling without the need for tedious protective labeling and depleting procedures. This method was introduced for the comprehensive analysis of N-terminal acetylated proteins from HepG2 cells. Several hundred N-terminal acetylation sites were readily identified in a single SCX flow-through fraction. Moreover, the N(α)-acetylated peptides of some protein isoforms were simultaneously observed in the SCX flow-through fraction, which indicated that this approach can be utilized to discriminate protein isoforms with very similar full sequences but different N-terminal sequences, such as β-actin/γ-actin, ERK1/ERK2, α-centractin/β-centractin, and ADP/ATP translocase 2 and 3. Compared to other methods, this method is relatively simple and can be directly implemented in a two-dimensional separation (SCX-RP)-mass spectrometry scheme for quantitative N-terminal proteomics using stable-isotope dimethyl labeling.

List omics technologies comprised in system biology.

System biology combines various omics technologies such as genomics, transcriptomics, proteomics, metabolomics, epigenomics, glucomics, degradomics and fluxomics.

Biomarkers are currently widely used to diagnose diseases, monitor treatments, and evaluate potential drug candidates. Research of differential Omics accelerate the advancements of biomarkers' discovery. By extracting biological knowledge from the 'omics' through integration, integrative system biology creates predictive models of cells, organs, biochemical processes and complete organisms, in addition to identifying human disease biomarkers. Recent development in high-throughput methods enables analysis of genome, transcriptome, proteome, and metabolome at an unprecedented scale, thus contributing to the deluge of experimental data in numerous public databases. Several integrative system biology approaches have been developed and applied to the discovery of disease biomarkers from databases. In this review, we highlight several of these approaches and identify future steps in the context of the field of integrative system biology. Since the main ultimate goal of farm animal raising is the production of proteins for human consumption, research tools to investigate proteins play a major role in farm animal and meat science. Indeed, proteomics has been applied to the field of farm animal science to monitor in vivo performances of livestock animals (growth performances, fertility, milk quality etc.), but also to further our understanding of the molecular processes at the basis of meat quality, which are largely dependent on the post mortem biochemistry of the muscle, often in a species-specific way. Post mortem alterations to the muscle proteome reflect the biological complexity of the process of "muscle to meat conversion," a process that, despite decades of advancements, is all but fully understood. This is mainly due to the enormous amounts of variables affecting meat tenderness per se, including biological factors, such as animal species, breed specific-characteristic, muscle under investigation. However, it is rapidly emerging that the tender meat phenotype is not only tied to genetics (livestock breeding selection), but also to extrinsic factors, such as the rearing environment, feeding conditions, physical activity, administration of hormonal growth promotants, pre-slaughter handling and stress, post mortem handling. From this intricate scenario, biochemical approaches and systems-wide integrated investigations (metabolomics, transcriptomics, interactomics, phosphoproteomics, mathematical modeling), which have emerged as complementary tools to proteomics, have helped establishing a few milestones in our understanding of the events leading from muscle to meat conversion. The growing integration of omics disciplines in the field of systems biology will soon contribute to take further steps forward. Traditional technologies to investigate system biology are limited by the detection of parameters resulting from the averages of large populations of cells, missing cells produced in small numbers, and attempting to uniform the heterogeneity. The advent of proteomics and genomics at a single-cell level has set the basis for an outstanding improvement in analytical technology and data acquisition. It has been well demonstrated that cellular heterogeneity is closely related to numerous stochastic transcriptional events leading to variations in patterns of expression among single genetically identical cells. The new-generation technology of single-cell analysis is able to better characterize a cell's population, identifying and differentiating outlier cells, in order to provide both a single-cell experiment and a corresponding bulk measurement, through the identification, quantification and characterization of all system biology aspects (genomics, transcriptomics, proteomics, metabolomics, degradomics and fluxomics). The movement of omics into single-cell analysis represents a significant and outstanding shift. Majority of eukaryotic proteins are glycosylated and their glycan moieties have numerous important structural, functional and regulatory roles. Because of structural complexity of glycans and technological limitations glycomics, and particularly glycoproteomics was not able to follow rapid progress in genomics and proteomics over last 30 years. However, the field of glycan has been progressing rapidly and first large-scale studies of the glycome have been completed recently. These studies have revealed significant differences in glycome composition between individuals, which may contribute to the human phenotypic variability. The current state-of-the-art in high-throughput glycomics and its integration with genomics, epigenomics and lipidomics is reviewed in this article. The field of metabolomics continues to grow rapidly over the last decade and has been proven to be a powerful technology in predicting and explaining complex phenotypes in diverse biological systems. Metabolomics complements other omics, such as transcriptomics and proteomics and since it is a 'downstream' result of gene expression, changes in the metabolome is considered to best reflect the activities of the cell at a functional level. Thus far, metabolomics might be the sole technology capable of detecting complex, biologically essential changes. As one of the omics technology, metabolomics has exciting applications in varied fields, including medical science, synthetic biology, medicine, and predictive modeling of plant, animal and microbial systems. In addition, integrated applications with genomics, transcriptomics, and proteomics provide greater understanding of global system biology. In this review, we discuss recent applications of metabolomics in microbiology, plant, animal, food, and medical science. Our knowledge on cyanobacterial molecular biology increased tremendously by the application of the "omics" techniques. Only recently, metabolomics was applied systematically to model cyanobacteria. Metabolomics, the quantitative estimation of ideally the complete set of cellular metabolites, is particularly well suited to mirror cellular metabolism and its flexibility under diverse conditions. Traditionally, small sets of metabolites are quantified in targeted metabolome approaches. The development of separation technologies coupled to mass-spectroscopy- or nuclear-magnetic-resoce-based identification of low molecular mass molecules presently allows the profiling of hundreds of metabolites of diverse chemical nature. Metabolome analysis was applied to characterize changes in the cyanobacterial primary metabolism under diverse environmental conditions or in defined mutants. The resulting lists of metabolites and their steady state concentrations in combination with transcriptomics can be used in system biology approaches. The application of stable isotopes in fluxomics, i.e. the quantitative estimation of carbon and nitrogen fluxes through the biochemical network, has only rarely been applied to cyanobacteria, but particularly this technique will allow the making of kinetic models of cyanobacterial systems. The further application of metabolomics in the concert of other "omics" technologies will not only broaden our knowledge, but will also certainly strengthen the base for the biotechnological application of cyanobacteria. Proteomics technology, a major component of system biology, has gained comprehensive attention in the area of medical diagnosis, drug development, and mechanism research. On the holistic and systemic theory, proteomics has a convergence with traditional Chinese medicine (TCM). In this review, we discussed the applications of proteomic technologies in diseases-TCM syndrome combination researches. We also introduced the proteomic studies on the in vivo and in vitro effects and underlying mechanisms of TCM treatments using Chinese herbal medicine (CHM), Chinese herbal formula (CHF), and acupuncture. Furthermore, the combined studies of proteomics with other "-omics" technologies in TCM were also discussed. In summary, this report presents an overview of the recent advances in the application of proteomic technologies in TCM studies and sheds a light on the future global and further research on TCM.

Rindopepimut is an analog of which growth factor?

Rindopepimut is an analog of EGFRvIII. It is being tested for treatment of glioblastoma multiforme

Celldex Therapeutics is developing rindopepimut (CDX-110), a 14-mer injectable peptide vaccine for the potential treatment of glioblastoma multiforme (GBM). Rindopepimut specifically targets a novel junctional epitope of the EGFR deletion mutant EGFRvIII, which is a constitutively active receptor that is expressed in approximately 60 to 70% of patients with GBM. EGFRvIII expression is correlated with worse prognosis and reduced overall survival. Importantly, EGFRvIII is not expressed in normal brain tissue, making it an excellent therapeutic target. Preclinical studies demonstrated lasting tumor regression and increased survival times, as well as efficient generation of EGFRvIII-specific humoral and cellular immune responses, in animals expressing EGFRvIII and vaccinated with rindopepimut. Phase I and II clinical trials in patients with GBM demonstrated significantly increased median time to progression and overall survival time in those vaccinated with rindopepimut compared with matched historical controls. Only limited side effects have been observed in patients. Given these results, rindopepimut is an extremely promising therapy for patients with GBM. Phase I and II clinical trials in patients with GBM were ongoing at the time of publication. In the future, it may be beneficial to combine rindopepimut with other treatment modalities to further prolong survival. Glioblastoma multiforme (GBM) is the most common and deadly of the human brain cancers. The EGF receptor is often amplified in GBM and provides a potential therapeutic target. However, targeting the normal receptor is complicated by its nearly ubiquitous and high level of expression in certain tissues. A naturally occurring deletion mutant of the EGF receptor, EGFRvIII, is a constitutively active variant originally identified in a high percentage of brain cancer cases, and more importantly is rarely found in normal tissue. A peptide vaccine, rindopepimut (CDX-110, Celldex Therapeutics), is directed against the novel exon 1-8 junction produced by the EGFRvIII deletion, and it has shown high efficacy in preclinical models. Recent Phase II clinical trials in patients with newly diagnosed GBM have shown EGFRvIII-specific immune responses and significantly increased time to progression and overall survival in those receiving vaccine therapy, as compared with published results for standard of care. Rindopepimut therefore represents a very promising therapy for patients with GBM. Glioblastoma multiforme (GBM) is the most common and aggressive glial cell-derived primary tumor. Current standard of care for patients with GBM includes maximal tumor resection plus adjuvant radiotherapy and temozolomide chemotherapy, increasing median overall survival to a mere 15 months from diagnosis. Because these therapies are inherently nonspecific, there is an increased likelihood of off-target and incomplete effects; therefore, targeted modalities are required for enhanced safety and efficacy. Rindopepimut is emerging as a safe and potentially effective drug for the treatment of GBM. Rindopepimut consists of a 14-mer peptide that spans the length of EGF receptor variant III, a mutant variant of EGF receptor found on approximately 30% of primary GBM, conjugated to the carrier protein keyhole limpet hemocyanin. Vaccination with rindopepimut has been shown to specifically eliminate cells expressing EGF receptor variant III. Phase II clinical trials have suggested that vaccination of newly diagnosed GBM patients with rindopepimut plus adjuvant granulocyte-macrophage colony-stimulating factor results in prolonged progression-free and overall survival with minimal toxicity. This review will outline the development of rindopepimut, as well as the current status of this vaccine.

Which gene mutations are responsible for isolated Non-compaction cardiomyopathy?

The gene mutations that have been shown to be the causes of isolated non-compaction cardiomyopathy are alpha-tropomyosin, alpha-tropomyosin, troponin T and desmoplakin

Isolated non-compaction of the ventricular myocardium (INVM), sometimes referred to as 'spongy myocardium', is a congenital and exceedingly rare cardiomyopathy. Isolated ventricular non-compaction occurs in the absence of other structural heart diseases and, hypothetically, it is due to the arrest of myocardial morphogenesis. Isolated non-compaction of the ventricular myocardium may manifest itself from infancy to young adulthood with a high mortality rate. Both sexes are affected. In our study, we present a case of INVM (left and right ventricles) in a 3-year-old girl, diagnosed by two-dimensional echocardiography. The anomaly presented as a restrictive cardiomyopathy. The girl was admitted to our hospital with heart failure, when she was 10 months old. She was treated with dopamine, digoxin, furosemide, spironolactone, and acenocoumarol and her condition improved. Presently, the girl remains asymptomatic and for 3 years of follow-up, her development has been almost normal. We here describe the genetic background of this disorder (based on a literature review). Noncompaction of the ventricular myocardium (NVM) is the morphological hallmark of a rare familial or sporadic unclassified heart disease of heterogeneous origin. NVM results presumably from a congenital developmental error and has been traced back to single point mutations in various genes. The objective of this study was to determine the underlying genetic defect in a large German family suffering from NVM. Twenty four family members were clinically assessed using advanced imaging techniques. For molecular characterization, a genome-wide linkage analysis was undertaken and the disease locus was mapped to chromosome 14ptel-14q12. Subsequently, two genes of the disease interval, MYH6 and MYH7 (encoding the alpha- and beta-myosin heavy chain, respectively) were sequenced, leading to the identification of a previously unknown de novo missense mutation, c.842G>C, in the gene MYH7. The mutation affects a highly conserved amino acid in the myosin subfragment-1 (R281T). In silico simulations suggest that the mutation R281T prevents the formation of a salt bridge between residues R281 and D325, thereby destabilizing the myosin head. The mutation was exclusively present in morphologically affected family members. A few members of the family displayed NVM in combination with other heart defects, such as dislocation of the tricuspid valve (Ebstein's anomaly, EA) and atrial septal defect (ASD). A high degree of clinical variability was observed, ranging from the absence of symptoms in childhood to cardiac death in the third decade of life. The data presented in this report provide first evidence that a mutation in a sarcomeric protein can cause noncompaction of the ventricular myocardium. Cardiac involvement is frequent in myotonic dystrophy type 2 (DM2) with dilated cardiomyopathy and severe arrhythmias having been reported. Left ventricular non-compaction is a cardiomyopathy often associated with neuromuscular disorders. We report the case of a 61-year-old man with DM2 treated for 5 years for a suspected dilated cardiomyopathy. Echocardiography showed left ventricular non-compaction typical pattern, with prominent apical trabeculations and intertrabecular spaces perfused from ventricular cavity. MRI confirmed the diagnosis. Physicians should be aware of the risk of severe cardiac complications in DM2 patients. Left ventricular non-compaction diagnosis is often overlooked. Neurological examination should be performed in all patients with left ventricular non-compaction. Accumulating data suggest a link between alterations/deficiencies in cytoskeletal proteins and the progression of cardiomyopathy and heart failure, although the molecular basis for this link remains unclear. Cypher/ZASP is a cytoskeletal protein localized in the sarcomeric Z-line. Mutations in its encoding gene have been identified in patients with isolated non-compaction of the left ventricular myocardium, dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy. To explore the role of Cypher in myocardium and to better understand molecular mechanisms by which mutations in cypher cause cardiomyopathy, we utilized a conditional approach to knockout Cypher, specially in either developing or adult myocardium. Cardiac-specific Cypher knockout (CKO) mice developed a severe form of DCM with disrupted cardiomyocyte ultrastructure and decreased cardiac function, which eventually led to death before 23 weeks of age. A similar phenotype was observed in inducible cardiac-specific CKO mice in which Cypher was specifically ablated in adult myocardium. In both cardiac-specific CKO models, ERK and Stat3 signaling pathways were augmented. Finally, we demonstrate the specific binding of Cypher's PDZ domain to the C-terminal region of both calsarcin-1 and myotilin within the Z-line. In conclusion, our studies suggest that (i) Cypher plays a pivotal role in maintaining adult cardiac structure and cardiac function through protein-protein interactions with other Z-line proteins, (ii) myocardial ablation of Cypher results in DCM with premature death and (iii) specific signaling pathways participate in Cypher mutant-mediated dysfunction of the heart, and may in concert facilitate the progression to heart failure. Left ventricular non-compaction (LVNC) is a rare disorder of endomyocardial morphogenesis that results in multiple trabeculations and deep intertrabecular recesses filled with direct blood flow from the left ventricular cavity. LVNC is attracting increasing interest as a model for the study of cardiomyopathies, since it is a genetically heterogeneous disorder which varies greatly in clinical presentation and age of onset. The authors present the case of a young black male with progressive congestive heart failure of 2-3 years' evolution. The investigation, which included transthoracic echocardiography (contrast and 3D), transesophageal echocardiography and cardiac magnetic resoce imaging, showed LVNC and severe aortic regurgitation, with severe left ventricular systolic dysfunction. The family history was suggestive of genetically transmitted disease and genetic study of the TAZ gene at locus Xq28 identified the mutation p.Phe128Ser (c.383T>C), the first description of this mutation in a patient with LVNC. The patient underwent aortic valve replacement, with excellent clinical evolution, regression of left ventricular dimensions and global systolic functio Aortic regurgitation (not related to LVNC) was the determining factor in the clinical expression. However, the excellent reverse remodeling that occurred after surgery highlights the heterogeneity of myocardial behavior in LVNC patients. Ventricular noncompaction is a form of cardiomyopathy where increased trabeculation is present frequently affecting the left ventricle and resembling an embryonic state of heart development. Clinically, left ventricular noncompaction may manifest as congestive heart failure, arrhythmias, and/or thromboembolic events. There are multiple genes linked to noncompaction, but recently, sarcomere gene mutations were found in both familial and sporadic cases of noncompaction. The association of noncompaction with sarcomere mutations supports the classification of ventricular noncompaction as cardiomyopathy and raises interesting questions regarding the continuum of hypertrophic cardiomyopathy, dilated cardiomyopathy, and noncompaction. The mutational spectrum of sarcomere genes in these disorders highlights the importance of the MYH7 gene encoding beta-myosin heavy chain and ACTC1 encoding the cardiac actin gene. Intriguingly, these mutations also share a low but definitive incidence of congenital heart malformations including septal defects. These human genetic findings support that normal myocardial and sarcomere function are required for proper compaction and septation and that these mutations also portend a high risk of developing heart failure in later life. AIMS: Left ventricular non-compaction (LVNC) is caused by mutations in multiple genes. It is still unclear whether LVNC is the primary determit of cardiomyopathy or rather a secondary phenomenon with intrinsic cardiomyocyte dysfunction being the actual cause of the disease. Here, we describe a family with LVNC due to a novel missense mutation, pE96K, in the cardiac troponin T gene (TNNT2). METHODS AND RESULTS: The novel mutation was identified in the index patient and all affected relatives, but not in 430 healthy control individuals. Mutations in known LVNC-associated genes were excluded. To investigate the pathophysiological implications of the mutation, we generated transgenic mice expressing human wild-type cTNT (hcTNT) or a human troponin T harbouring the pE96K mutation (mut cTNT). Animals were characterized by echocardiography, histology, and gene expression analysis. Mut cTNT mice displayed an impaired left ventricular function and induction of marker genes of heart failure. Remarkably, left ventricular non-compaction was not observed. CONCLUSION: Familial co-segregation and the cardiomyopathy phenotype of mut cTNT mice strongly support a causal relationship of the pE96K mutation and disease in our index patient. In addition, our data suggest that a non-compaction phenotype is not required for the development of cardiomyopathy in this specific TNNT2 mutation leading to LVNC. BACKGROUND: Isolated non-compaction cardiomyopathy (NCCM) was first described in 1984. This disorder, a primary genetic cardiomyopathy, is now attracting increased attention. METHOD: The current state of the epidemiology, pathogenesis, pathophysiology, clinical features, diagnosis, treatment, and prognosis of NCCM are discussed on the basis of a review of selected literature as well as the authors' personal experience. RESULTS: The pathogenesis of NCCM is thought to involve a genetically determined disturbance of the myocardial compaction process during fetal endomyocardial morphogenesis. It is not accompanied by any other cardiac anomalies. Echocardiography is the diagnostic method of choice. The diagnosis is based on the following echocardiographic criteria: the presence of at least 4 prominent trabeculations and deep intertrabecular recesses, blood flow from the ventricular cavity into the intertrabecular recesses, and a typical bilaminar structure of the affected portion of the left ventricular myocardium. NCCM can also be diagnosed with magnetic resoce imaging of the heart. The clinical severity of NCCM is variable; its manifestations include heart failure, thromboembolic events, and arrhythmias. The treatment is symptom-based. Patients with symptomatic NCCM have a poor prognosis. CONCLUSION: NCCM is a type of cardiomyopathy that was first described 25 years ago. Its molecular genetic basis is not yet fully clear, and the same is true of its diagnosis, treatment, and prognosis. Further study of these matters is needed. Non-compaction of the left ventricular myocardium (LVNC) has gained increasing recognition during the last 25 years. There is a morphological trait of the myocardial structure with a spectrum from normal variants to the pathological phenotype of LVNC, which reflects the embryogenic structure of the human heart due to an arrest in the compaction process during the first trimester. It must be cautioned not to overdiagnose LVNC: the morphological spectrum of trabeculations, from normal variants to pathological trabeculations with the morphological feature of LVNC must be carefully considered. The classical triad of complications are heart failure, arrhythmias, including sudden cardiac death, and systemic embolic events. Non-compaction of the left ventricular myocardium can occur in isolation or in association with congenital heart defects (CHDs), genetic syndromes, and neuromuscular disorders among others. The clinical spectrum is wide and the outcome is more favourable than in previously described populations with a negative selection bias. Familial occurrence is frequent with autosomal domit and X-linked transmissions. Different mutations in sarcomere protein genes were identified and there seems to be a shared molecular aetiology of different cardiomyopathic phenotypes, including LVNC, hypertrophic and dilated cardiomyopathies. Thus, genetic heterogeneity, with an overlap of different phenotypes, and the variability of hereditary patterns, raise the questions whether there is a morphological trait from dilated/hypertrophic cardiomyopathy to LVNC and what are the triggers and modifiers to develop either dilated, hypertrophic cardiomyopathy, or LVNC in patients with the same mutation. The variety in clinical presentation, the genetic heterogeneity, and the phenotype of the first transgenetic animal model of an LVNC-associated mutation question the hypothesis that LVNC be a distinct cardiomyopathy: it seems to be rather a distinct phenotype or phenotypic, morphological expression of different underlying diseases than a distinct cardiomyopathy. BACKGROUND: Left ventricular noncompaction of the myocardium (LVNC) has been recognized as a cardiomyopathy with a genetic etiology. Mutations in genes encoding sarcomere proteins were shown to be associated with LVNC. We evaluated the potential clinical impact of genetic analysis of sarcomere genes in patients with LVNC. METHODS AND RESULTS: We identified 5 mutations in cardiac myosin-binding protein C (MYBPC3) and 2 mutations in α-tropomyosin (TPM1) in a cohort of unrelated adult probands with isolated LVNC. The mutations in MYBPC3 and TPM1 and in 6 other previously reported sarcomere genes in this cohort resulted in a total of 18 (29%) heterozygous mutations in 63 probands. β-myosin heavy chain (MYH7) was the most prevalent disease gene and accounts for 13% of cases, followed by MYBPC3 (8%). Comparing sarcomere mutation-positive and mutation-negative LVNC probands showed no significant differences in terms of average age, myocardial function, and presence of heart failure or tachyarrhythmias at initial presentation or at follow-up. Familial disease was found in 16 probands of whom 8 were sarcomere mutation positive. Nonpenetrance was detected in 2 of 8 mutation-positive families with LVNC. CONCLUSIONS: Mutations in sarcomere genes account for a significant (29%) proportion of cases of isolated LVNC in this cohort. The distribution of disease genes confirms genetic heterogeneity and opens new perspectives in genetic testing in patients with LVNC and their relatives at high risk of inheriting the cardiomyopathy. The presence or absence of a sarcomere gene mutation in LVNC cannot be related to the clinical phenotype. Two sons of a consanguineous marriage developed biventricular cardiomyopathy. One boy died of severe heart failure at the age of 6 years, the other was transplanted because of severe heart failure at the age of 10 years. In addition, focal palmoplantar keratoderma and woolly hair were apparent in both boys. As similar phenotypes have been described in Naxos disease and Carvajal syndrome, respectively, the genes for plakoglobin (JUP) and desmoplakin (DSP) were screened for mutations using direct genomic sequencing. A novel homozygous 2 bp deletion was identified in an alternatively spliced region of DSP. The deletion 5208_5209delAG led to a frameshift downstream of amino acid 1,736 with a premature truncation of the predomit cardiac isoform DSP-1. This novel homozygous truncating mutation in the isoform-1 specific region of the DSP C-terminus caused Carvajal syndrome comprising severe early-onset heart failure with features of non-compaction cardiomyopathy, woolly hair and an acantholytic form of palmoplantar keratoderma in our patient. Congenital hair abnormality and manifestation of the cutaneous phenotype in toddler age can help to identify children at risk for cardiac death. Isolated non-compaction cardiomyopathy is a rare disease that is likely to develop in the embryonic period. It is caused by the intrauterine arrest of the myocardial compaction process in the beginning of the fetal development. It is characterized by prominent myocardial trabeculations and deep intertrabecular recesses, as well as the thickening of the myocardium into two distinct layers (compacted and not compacted). Even though this disease is said to be prevalent in the pediatric population or together with congenital heart disease, one can understand that this disease occurs in isolation, because the diagnosis is becoming more common in adult patients that have no other heart disease. The clinical manifestations vary greatly, because they range from absence of symptoms to congestive heart failure, arrhythmias and systemic thromboembolism. Echocardiography is the most widely used diagnostic procedure, but the little knowledge about this disease, its similarity to other myocardial diseases and the limitation of the echocardiographic technique used delay the diagnosis. The purpose of this review is to show that that other imaging techniques, such as MRI, CT and left ventriculography have emerged as diagnostic alternatives. We report on a German family presenting with a predomitly distal myopathy primarily affecting anterior compartments of lower legs in childhood. Proximal lower limb and hip girdle weakness developed later in early adulthood in the female index patient and likewise in her mother. Consecutive muscle biopsy findings were first attributed to a mild congenital myopathy and later on interpreted as neurogenic changes without clear signs of a myopathy. Molecular genetic analysis was performed because of the clinical impression of a distal myopathy combined with domit inheritance. The heterozygous mutation c.349G>A (p.D117N) in the ZASP gene could be found. This mutation had been previously associated with an adult-onset, isolated, dilated left ventricular non-compaction cardiomyopathy (OMIM*605906.0007), which was not present in our patients. Our data show that this mutation can be associated with an isolated skeletal muscle phenotype. Second, mutation analysis of the ZASP gene is suggested for distal myopathies of any age, even in cases of uncharacteristic muscle biopsy findings on routine analysis. We report on two prenatal ultrasound diagnoses of left ventricular non-compaction cardiomyopathy (LVNC) associated with mutation of the cardiac β-myosin heavy chain gene (MYH7). LVNC is characterized by a trabecular meshwork and deep intertrabecular myocardial recesses communicating with the left ventricular cavity. Clinical features range from non-penetrant disease in adult carriers to heart failure, arrhythmia and thromboembolism. Both cases showed cardiomegaly on prenatal ultrasound examinations, with features indicating non-compaction of the myocardium apparent in the third trimester. Mutations in the MYH7 gene were identified postnatally in each case in both the proband and the father. One infant underwent surgical mitral valvuloplasty and a mechanical valve implant later; in the other, left ventricular function was unimpaired at birth. Cardiac function in both cases remained stable at last follow-up. These cases highlight the importance of prenatal ultrasound diagnosis of LVNC and the need for cardiologic and molecular testing of first-degree relatives who may be unknown carriers of an MYH7 mutation. Left ventricular non-compaction cardiomyopathy is a rare congenital cardiomyopathy that affects both children and adults. Since the clinical manifestations are not sufficient to establish diagnosis, echocardiography is the diagnostic tool that makes it possible to document ventricular non-compaction and establish prognostic factors. We report a 47-year-old woman with a history of dilated cardiomyopathy with unknown etiology. Echocardiography showed mild left ventricular enlargement with severe systolic dysfunction (EF = 20-25%). According to cardiac magnetic resoce imaging findings non-compaction left ventricle with hypertrophic cardiomyopathy was considered, and right ventricular septal biopsy was recommended. Right ventricular endomyocardial biopsy showed moderate hypertrophy of cardiac myocytes with foci of myocytolysis and moderate interstitial fibrosis. No evidence of infiltrative deposition was seen. BACKGROUND: Dilated cardiomyopathy (DCM) is characterized by idiopathic dilatation and systolic contractile dysfunction of the ventricle(s) leading to an impaired systolic function. The origin of DCM is heterogeneous, but genetic transmission of the disease accounts for up to 50% of the cases. Mutations in alpha-tropomyosin (TPM1), a thin filament protein involved in structural and regulatory roles in muscle cells, are associated with hypertrophic cardiomyopathy (HCM) and very rarely with DCM. METHODS AND RESULTS: Here we present a large four-generation family in which DCM is inherited as an autosomal domit trait. Six family members have a cardiomyopathy with the age of diagnosis ranging from 5 months to 52 years. The youngest affected was diagnosed with dilated and non-compaction cardiomyopathy (NCCM) and died at the age of five. Three additional children died young of suspected heart problems. We mapped the phenotype to chromosome 15 and subsequently identified a missense mutation in TPM1, resulting in a p.D84N amino acid substitution. In addition we sequenced 23 HCM/DCM genes using next generation sequencing. The TPM1 p.D84N was the only mutation identified. The mutation co-segregates with all clinically affected family members and significantly weakens the binding of tropomyosin to actin by 25%. CONCLUSIONS: We show that a mutation in TPM1 is associated with DCM and a lethal, early onset form of NCCM, probably as a result of diminished actin binding caused by weakened charge-charge interactions. Consequently, the screening of TPM1 in patients and families with DCM and/or (severe, early onset forms of) NCCM is warranted. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction. BACKGROUND: We report an Italian family in which the proband showed a severe phenotype characterized by the association of congenital fiber type disproportion (CFTD) with a left ventricular non-compaction cardiomyopathy (LVNC). This study was focused on the identification of the responsible gene/s. METHODS AND RESULTS: Using the whole-exome sequencing approach, we identified the proband homozygous missense mutations in two genes, the myosin heavy chain 7B (MYH7B) and the integrin alpha 7 (ITGA7). Both genes are expressed in heart and muscle tissues, and both mutations were predicted to be deleterious and were not found in the healthy population.The R890C mutation in the MYH7B gene segregated with the LVNC phenotype in the examined family. It was also found in one unrelated patient affected by LVNC, confirming a causative role in cardiomyopathy.The E882K mutation in the ITGA7 gene, a key component of the basal lamina of muscle fibers, was found only in the proband, suggesting a role in CFTD. CONCLUSIONS: This study identifies two novel disease genes. Mutation in MYH7B causes a classical LVNC phenotype, whereas mutation in ITGA7 causes CFTD. Both phenotypes represent alterations of skeletal and cardiac muscle maturation and are usually not severe. The severe phenotype of the proband is most likely due to a synergic effect of these two mutations.This study provides new insights into the genetics underlying Mendelian traits and demonstrates a role for digenic inheritance in complex phenotypes. Isolated Left Ventricular Non Compaction Cardiomyopathy (LVNCC) is a rare genetic cardiomyopathy characterized by a thickened left ventricle with two distinct layers - an inner noncompacted (spongy) layer and an outer compact (dense) layer. The spongy layer is composed of deep intertrabecular recesses. Familial and sporadic forms are known to exist and there is significant genetic heterogeneity among the inherited forms. Symptoms vary and range from asymptomatic to severe heart failure and sudden death. The clinical diagnosis of LVNCC can be challenging partly because there is currently no consensus for diagnostic criteria. As such, many affected individuals are, inopportunely, first diagnosed at post-mortem examination.

From which tissue was the NCI-H520 cell-line derived?

Non-small cell lung cancer (NSCLC) cell line NCI-H520. Squamous cell carcinoma cell line NCI-H520.

The antitumor effect of CGP41251 (4'-N-benzoyl staurosporine), a selective protein kinase C (PKC) inhibitor, was examined on two kinds of human non-small cell lung cancer (NSCLC) cell lines (adenocarcinoma: A549 and squamous cell carcinoma: NCI-H520). CGP41251 at 0.5 or 1.0 microM inhibited the proliferation of these tumor cell lines significantly; However, at 0.1 microM, it did not show any significant inhibition. Cell cycle analysis indicated that CGP41251 at 0.5 or 1.0 microM arrested the cell cycle progression at the G2/M phase up to 24 hr, but 0.1 microM did not. It seems that the antiproliferative action of CGP41251 against human NSCLC is related to G2/M accumulation. In NCI-H520, CGP41251 caused DNA re-replication without mitosis. In a nude mice xenograft, CGP41251 at a dose of 200 mg/kg showed antitumor activity against these cell lines. Histopathologically, expansion of central necrosis was observed, although no destruction of tumor nests was seen by CGP41251 administration. In both tumor tissues, the PKC activity of the particulate fraction was significantly decreased by CGP41251 treatment. From these results, it is thought that the antitumor activity of CGP41251 against human NSCLS is accompanied by the decrease of PKC activity in the particulate fraction. Moreover, the G2/M arrest of the cell cycle induced by CGP41251 might be important for the growth inhibitory action of this compound. Humoral hypercalcemia of maligcy, a frequent complication of squamous cell carcinomas of the lung, is mediated by the parathyroid hormone-related peptide (PTHrP). This study was undertaken to determine whether 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] and two nonhypercalcemic analogues. EB1089 and 22-oxa-1,25(OH)(2)D(3) (OCT), suppress PTHrP gene expression in a human lung squamous cancer cell line, NCI H520. All three compounds (1) decreased steady-state PTHrP mRNA and secreted peptide levels via a transcriptional mechanism; (2) modulated promoter activity of 1,25(OH)(2)D(3)-responsive DNA sequences; and (3) activated the vitamin D receptor (VDR) both in vitro and in vivo. Thus, EB1089 and OCT inhibit PTHrP gene expression in NCI H520 cells and modulate gene expression through the same mechanism as 1,25(OH)(2)D(3), namely, activation of the VDR. 1,25(OH)(2)D(3) is hypercalcemic in vivo. However, the noncalcemic analogues EB1089 and OCT have a therapeutic potential through suppression of PTHrP gene transcription. PTH-related peptide (PTHrP) mediates the syndrome of humoral hypercalcemia of maligcy, a frequent complication of squamous cell carcinomas of the lung. This study was undertaken to determine whether 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] and two nonhypercalcemic analogs, EB1089 and 22-oxa-1,25-(OH)2D3 (22-oxacalcitriol), suppress serum- and epidermal growth factor (EGF)-induced PTHrP gene expression in a human lung squamous cancer cell line, NCI H520. PTHrP expression was up-regulated by serum and EGF in a concentration- and time-dependent manner. Nuclear run-on analysis showed that this induction was mediated via a transcriptional mechanism, and that sequences within promoter 1 were responsible. All three vitamin D3 compounds decreased both basal and serum- and EGF-induced steady state PTHrP messenger RNA and secreted peptide levels. These effects were again mediated via a transcriptional mechanism through sequences within promoter 1. All three vitamin D3 compounds also decreased the proliferation of NCI H520 cells in a concentration- and time-dependent manner. 1,25-(OH)2D3 is hypercalcemic in vivo. However, the noncalcemic analogs EB1089 and 22-oxa-1,25-(OH)2D3 have therapeutic potential, as they suppress not only the basal but also the growth factor-stimulated levels of PTHrP in a cancer cell line associated with hypercalcemia. Neuroendocrine differentiation of lung tumours is characterised by the expression of several neuroendocrine markers and is confined mostly to specific histological subtypes, i.e. small cell carcinomas and carcinoids. One of the markers seen in neuroendocrine tumours, high activity of the aromatic L-amino acid decarboxylase (AADC), is helpful in distinguishing the classic and variant small cell lung tumour subtypes. Here, we have analysed the expression and quantified the level of mRNA coding for AADC in human tumour cell lines by use of the reverse transcription and polymerase chain reaction (RT-PCR). High amounts of mRNA were detected in classic small cell lung carcinomas and a neuroblastoma cell line. Other cell lines (melanomas, non-small cell lung carcinomas and osteosarcoma) also showed AADC expression, but the levels were 2-3 orders lower. Also, the tissue-specific (neuronal versus liver-specific) mRNA type has been estimated. Small cell lung carcinomas, neuroblastoma and melanoma expressed messenger RNA specific for neuronal tissues. Importantly, the non-small cell lung carcinoma cell lines expressed either liver-specific (non-neuronal) mRNA (cell line A549) or predomitly the neuronal (cell line NCI-H520) AADC message. These data indicate that a range of tumour cell lines transcribe the AADC gene and that two distinct types of AADC mRNA which reflect the embryonal (neuronal or non-neuronal) origin of the tumour may be produced in non-small cell lung cancer cells. Cysteine-rich protein 61 (Cyr61) is a member of a family of growth factor-inducible immediate-early genes. It regulates cell adhesion, migration, proliferation, and differentiation and is involved in tumor growth. In our experiments, the role of Cyr61 in non-small cell lung cancer (NSCLC) was examined. Expression of Cyr61 mRNA was decreased markedly in four of five human lung tumor samples compared with their normal matched lung samples. NSCLC cell lines NCI-H520 and H460, which have no endogenous Cyr61, formed 60-90% fewer colonies after being transfected with a Cyr61 cDNA expression vector than cells transfected with the same amount of empty vector. After stable transfection of a Cyr61 cDNA expression vector, proliferation of both H520-Cyr61 and H460-Cyr61 sublines decreased remarkably compared with the cells stably transfected with empty vector. The addition of antibody against Cyr61 partially rescued the growth suppression of both H520-Cyr61 and H460-Cyr61 cells. Cell cycle analysis revealed that both H520-Cyr61 and H460-Cyr61 cells developed G(1) arrest, prominently up-regulated expression of p53 and p21(WAF1), and had decreased activity of cyclin-dependent kinase 2. The increase of pocket protein pRB2/p130 was also detected in these cells. Notably, both of the Cyr61-stably transfected lung cancer cell lines developed smaller tumors than those formed by the wild-type cells in nude mice. Taken together, we conclude that Cyr61 may play a role as a tumor suppressor in NSCLC. Juvenile Batten disease is a neurodegenerative disease caused by accelerated apoptotic death of photoreceptors and neurons attributable to defects in the CLN3 gene. CLN3 is antiapoptotic when overexpressed in NT2 neuronal precursor cells. CLN3 negatively modulates endogenous ceramide levels in NT2 cells and acts upstream of ceramide generation. Because defects in regulation of apoptosis are involved in the development of cancer, we evaluated the expression of CLN3 on both mRNA and protein levels in a variety of cancer cell lines and solid colon cancer tissue. We also observed the effect of the blocking of CLN3 protein expression on cancer cell growth, survival, ceramide production, and apoptosis by using an adenovirus-bearing antisense CLN3 construct. We show that CLN3 mRNA and protein are overexpressed in glioblastoma (U-373G and T98g), neuroblastoma (IMR-32 and SK-N-MC), prostate (Du145, PC-3, and LNCaP), ovarian (SK-OV-3, SW626, and PA-1), breast (BT-20, BT-549, and BT-474), and colon (SW1116, SW480, and HCT 116) cancer cell lines but not in pancreatic (CAPAN and As-PC-1) or lung (A-549 and NCI-H520) cancer cell lines. CLN3 is also up-regulated in mouse melanoma and breast carcinoma cancer cell lines. We found CLN3 expression is 22-330% higher than in corresponding normal colon control tissue in 8 of 10 solid colon tumors. An adenovirus-expressing antisense CLN3 (Ad-AS-CLN3) blocks CLN3 protein expression in DU-145, BT-20, SW1116, and T98g cancer cell lines as seen by Western blot. Blocking of CLN3 expression using Ad-AS-CLN3 inhibits growth and viability of cancer cells. It also causes elevation in endogenous ceramide production through de novo ceramide synthesis and results in increased apoptosis as shown by propidium iodide and JC-1 staining. This suggests that Ad-AS-CLN3 may be an option for therapy in some cancers. More importantly these results suggest that CLN3 is a novel molecular target for cancer drug discovery. The unique signal transduction pathways that distinguish non-small cell lung carcinoma (NSCLC) from small cell lung carcinoma (SCLC) are poorly understood. We investigated the ability of edelfosine, an inhibitor of phosphatidylinositol-specific phospholipase C (PLC) to inhibit cell viability among four NSCLC cell lines and four SCLC cell lines. The differential sensitivity of cells to edelfosine's cytostatic and cytotoxic effects has been attributed to edelfosine-induced changes in the activities of many enzymes, including c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinases (ERK), p38 kinase, and poly(ADP-ribose) polymerase (PARP). To investigate the role of these enzymes in edelfosine-induced cytotoxicity, we correlated edelfosine-induced changes in enzyme activity and cell viability among the different NSCLC and SCLC cell lines. We found that NSCLC cells are much more susceptible to the cytotoxic effects of this drug than are SCLC cells. Three out of the four edelfosine-sensitive NSCLC cell lines (NCI-H157, NCI-H520, NCI-H522) exhibit G2/M arrest, significant apoptosis and some degree of JNK activation in response to drug treatment. In contrast, none of the SCLC cell lines exhibit edelfosine-induced G2/M arrest or significant apoptosis. A comparison of the edelfosine-induced effects among the sensitive and resistant lung cancer lines indicates that there is little correlation between edelfosine-induced cytotoxicity and altered activities of JNK, ERK, p38, or cleavage of PARP. These results demonstrate that edelfosine-induced changes in JNK, ERK, p38, or PARP are not good predictors of cell susceptibility to edelfosine-induced cytotoxicity. Thus, edelfosine-induced inactivation of PLC may disrupt signaling cascades downstream of PLC that are unique to individual cellular environments. These findings also identify edelfosine as one of the few potential chemotherapeutic agents that has a greater cytotoxic effect against NSCLC cells than SCLC cells. The mouse parathyroid hormone-like hormone Pthlh(Pro) and Pthlh(Thr) variants are linked with susceptibility and resistance to skin carcinogenesis of Car-S and Car-R mice, respectively, and with in vitro effects (Oncogene, 19: 5324-5328, 2000). We have identified an additional Pthlh variant, consisting of Thr and three amino-acid changes in the C-terminus (Pthlh(SerAspTyr)), carried by an evolutionarily distant Mus spretus (SPRET/Ei) inbred strain. When transfected into NCI-H520 tumor cells, this Pthlh(SerAspTyr) variant did not stimulate tumor growth in nude mice. Analysis of cell adhesion, migration, and invasion patterns of Pthlh(Pro)-, Pthlh(Thr)-, and Pthlh(SerAspTyr)-transfected NCI-H520 cells revealed a 1.5-fold decrease in adhesion efficiency on both collagen type I and Matrigel, and a 5-6-fold increase in migration capability in Pthlh(Pro) transfectants as compared to nontransfected, vector-transfected, Pthlh(Thr)-, or Pthlh(SerAspTyr)-transfected cells. These findings suggest that the cancer modifier effects of the mouse Pthlh gene are mediated by differential cell adhesion and migration effects of PTHrP variants. BACKGROUND & OBJECTIVE: Bcl-2/E1B 19kDa interacting protein3-like (BNIP3L) gene is a tumor suppressor gene cloned from a human fetal liver cDNA library, which is located at 8p21, one of the high frequent regions of loss of heterozygosity (LOH) in lung carcinoma. BNIP3L protein can interact with antiapoptotic proteins, such as Bcl-2, Bcl-x(L), E1B19K, which promotes apoptosis. This study was designed to explore the correlation of alteration of expression and structure of BNIP3L gene with the progression of lung cancer. METHODS: The expression and structure of BNIP3L gene in 4 lung cancer cell strains and 30 tissues were determined by SP immunohistochemistry, immunoblot, semi-quantitative reverse transcription-PCR (RT-PCR), PCR-single strain conformation polymorphism (PCR-SSCP). RESULTS: (1) In 4 lung cancer cell strains, BNIP3L protein was not detected in A549, NCI-H460, NCI-H446, except for NCI-H520, in which the protein expression level was slightly lower than that in immortal bronchial epithelial cell strain HBE4-E6/E7. BNIP3L protein was observed in 46.7% (14/30) lung cancer tissues, while 100% (12/12) in normal lung tissues. The difference was significant in statistics (P< 0.05). (2) BNIP3L mRNA was detected in 4 lung cancer cell strains; and there existed no obvious discrepancy of the amount between these cell strains and HBE4-E6/E7. Absence or decrease of BNIP3L mRNA was observed in 26.7%(8/30) of lung cancer tissues. The average quantity of BNIP3L mRNA was 0.404+/-0.070 in lung cancer tissues, while 0.575+/-0.065 in paired normal lung tissues. The difference was significant in statistics (P< 0.05). In all the cancerous cell strains and tissues with BNIP3L mRNA, the products of RT-PCR were as long as those from their control samples in size, including the entire coding region, and no variation of BNIP3L gene structure such as absence, rearrangement, aberrant splicing were detected.(3) No point mutation was detected in all 6 exons of BNIP3L gene in 4 lung cancer cell strains and 30 tissues. CONCLUSION: BNIP3L protein expression was down-regulated in lung cancer, which might be involved in the occurrence and/or development of lung cancer. The down-regulation of BNIP3L protein expression in lung cancer was partly caused by the down-regulation of its transcription. The variation of gene structure may be not the reason of BNIP3L inactivity in lung cancer. Proteasome inhibitor PS-341 induces growth arrest and apoptosis of multiple myeloma (MM) cells via inactivation of NF-kappaB in vitro and has afforded some objective responses in individuals with relapsed, refractory MM. However, the activity of PS-341 against non-hematological maligcies remains to be fully elucidated. In this study, we found that PS-341 induced growth arrest and apoptosis of NCI-H520 and -H460 non-small cell lung cancer (NSCLC) cells in conjunction with markedly up-regulated levels of p21(waf1) and p53, and down-regulation of bcl-2 protein in these cells. Also, PS-341 caused phosphorylation of c-Jun NH(2)-terminal kinase (JNK) and c-Jun, and enhanced AP-1/DNA binding activities in these cells as measured by western blotting and enzyme-linked immunosorbent assay (ELISA), respectively. Interestingly, when the JNK/c-Jun/AP-1 signal pathway was disrupted by the JNK inhibitor SP600125, the ability of PS-341 to inhibit the growth of NSCLC cells and to up-regulate the levels of p21(waf1) in these cells was blunted, but the expression of p53 was sustained at a high level, suggesting that the JNK/c-Jun/AP-1 signal pathway might mediate the anti-lung cancer effects of PS-341, with p21(waf1) playing the central role. Thus, PS-341 might be useful for the treatment of individuals with NSCLC. The tyrosinase (Tyr) gene encodes the enzyme tyrosinase that catalyses the conversion of L-tyrosine into DOPA (3,4-dihydroxyphenylalanine)-quinone. The albino mutation abrogates functional activity of tyrosinase resulting in deficiency of melanin pigment production in skin and retina. Tyr maps to a region in the central position of Chromosome 7 that contains a skin tumor-modifier locus. We rescued the albino mutation in transgenic mice to assess a possible role of Tyr gene in two-stage skin carcinogenesis. Transgenic expression of the functional Tyr(Cys) allele in albino mice (Tyr(Ser)) caused a reduction in skin papilloma multiplicity, in four independent experiments and at three dose levels of DMBA (9,10-dimethyl-1,2-benzanthracene). In vitro mechanistic studies demonstrated that transfection of the Tyr(Cys) allele in a human squamous cell carcinoma cell line (NCI-H520) increases tyrosinase enzyme activity and confers resistance to hydrogen peroxide-induced oxidative DNA damage. These results provide direct evidence that the Tyr gene can act as a skin cancer-modifier gene, whose mechanism of action may involve modulation of oxidative DNA damage. The tumor suppressor gene DICE1 is located within a previously reported critical region of loss of heterozygosity on chromosome 13q14.3. Expression of the remaining DICE1 allele is down-regulated in non-small cell lung carcinomas. Ectopic expression of DICE1 cDNA by DICE1-green fluorescent protein fusion constructs resulted in inhibition of colony formation of human non-small cell lung carcinoma cell line SK-MES-1 and NCI-H520 and prostate carcinoma cell line DU145. In IGF-IR transformed Balb/c 3T3, DICE1 substantially sup-pressed growth in soft agar. These results demonstrate that DICE1 has a growth-suppressing activity and interferes with anchorage-independent growth of IGF-IR transformed tumor cells dependent upon IGF-I signaling. Heptaplatin, cis-malonato [(4R,5R)-4,5-bis (amino-methyl)-2-isopropyl-1,3-dioxolane] platinum(II) (SKI-2053R, Sunpla) is a new platinum derivative with anti-tumor activity comparable to cisplatin on various cancer cell lines. Preclinical studies suggest that it is less nephrotoxic than cisplatin. This study was undertaken to examine the combined effect of heptaplatin and ionizing radiation on two established human squamous carcinoma cell lines (NCI-H520, SQ20B). The cytotoxic activity of heptaplatin was concentration-dependent in both cell lines. When low dose heptaplatin was combined with high dose ionizing radiation, there was an additive cytotoxic effect on NCI-H520 cells (P < 0.05), while a moderate dose of heptaplatin and a low dose of ionizing radiation had an additive cytotoxic effect on the growth of SQ20B cells (P < 0.05). FACS analysis and DAPI staining showed that their additive cytotoxic effects were correlated with the induction of apoptosis. Further studies are warranted using heptaplatin and ionizing radiation in squamous cell carcinoma as a substitute for cisplatin. The RASSF8 gene, which maps close to the KRAS2 gene, contains a RAS-associated domain and encodes a protein that is evolutionarily conserved from fish to humans. Analysis of the RASSF8 transcript revealed a complex expression pattern of 5'-UTR mRNA isoforms in normal lung and in lung adenocarcinomas (ADCAs), with no apparent differences. However, RASSF8 gene transcript levels were approximately seven-fold-lower in lung ADCAs as compared to normal lung tissue. Expression of RASSF8 protein by transfected lung cancer cells led to inhibition of anchorage-independent growth in soft agar in A549 cells and reduction of clonogenic activity in NCI-H520 cells. These results raise the possibility protein encoded by RASSF8 is a novel tumor suppressor for lung cancer. PURPOSE: Whole-genome scan association analysis was carried out to identify genetic variants predictive of lung cancer risk in smokers and to confirm the identified variants in an independent sample. PATIENTS AND METHODS: A case-control study was performed using two pools consisting of DNA from 322 German smoking lung cancer patients and 273 healthy smoking controls, respectively. A replication study was carried out using 254 Italian lung adenocarcinoma (ADCA) patients and 235 healthy controls. RESULTS: Patients with genotypes GG or CG for the rs1862214 single nucleotide polymorphism, 5' upstream of the programmed cell death 5 (PDCD5) gene, compared with those with the common genotype CC showed an increased risk of lung cancer (odds ratio, 1.6; 95% CI, 1.2 to 2.1) and a higher incidence of poor clinical stage disease (hazard ratio [HR], 1.9; 95% CI, 1.1 to 3.4; P = .023), nodal involvement (HR, 1.9; 95% CI, 1.1 to 3.6; P = .033), and short-term survivorship (HR, 1.8; 95% CI, 1.2 to 2.6, P = .003). PDCD5 mRNA expression levels were approximately 2.4-fold lower in lung ADCA as compared to normal lung tissue. Human NCI-H520 cancer cells transfected with PDCD5 cDNA showed decreased colony-forming ability. CONCLUSION: These results suggest that the rs1862214 polymorphism in PDCD5 is predictive for lung cancer risk and prognosis, and that PDCD5 may represent a novel tumor suppressor gene influencing lung cancer. BACKGROUND: Inactivation of retinoblastoma (RB) tumor suppressor function occurs frequently in lung cancer. Short-hairpin RNA can be constructed to target specific sequences and efficiently knock down protein expression. We developed a short-hairpin RNA approach to specifically target Rb in lung cancer cells to determine the influence of RB knockdown on proliferation. METHODS: NCI-H520 human lung cancer cells (wild-type Rb) were transfected with pMSCVpuro-Rb3C, a plasmid containing a short-hairpin sequence targeted to human Rb. Transfectants harboring the construct were selected with puromycin. Loss of RB expression in selected cell populations was determined by immunoblotting. Proliferating cells were counted to establish growth rates. Retinoblastoma-proficient and RB-deficient tumor growth was monitored in nude mice. RESULTS: Transfection with pMSCVpuro-Rb3C dramatically diminished RB expression and led to aberrant expression of RB-regulated genes. Cells harboring pMSCVpuro-Rb3C grew at an increased rate compared with control cells: 480.6 +/- 37.7 versus 159.4 +/- 36.2 (relative cell count at 12 days). Tumor growth in nude mice also increased with RB knockdown compared with control mice: 135.2 +/- 73.6 mm3 versus 40.0 +/- 17.0 mm3 (tumor volume at 10 days). CONCLUSIONS: Inhibition of RB expression is efficiently achieved in lung cancer cells with short-hairpin RNA. Genetic targets of RB are deregulated with RB knockdown. Retinoblastoma depletion increases growth in vitro and in murine xenografts. These studies indicate that even in the context of an established tumor cell line, RB limits tumorigenic proliferation. Additionally, this model will serve as an ideal system to evaluate the role of RB activity on therapeutic response. Aberrant expression of COX-2 occurs in many types of maligcies including colon and lung cancers, and is implicated in development and progression of cancer. The molecular mechanisms associated with aberrant expression of COX-2 in lung cancer cells remain to be fully elucidated. In this study, we found that non-small cell lung cancer (NSCLC) NCI-H520 and NCI-H460 cells constitutively expressed COX-2 and produced prostaglandin E2 (PGE2) as measured by Western blotting and enzyme-linked immunosorbent assay (ELISA), respectively. Reporter assays showed that transcriptional regulation of COX-2 was blunted when either the NF-IL6 (C/EBPbeta) or nuclear factor-kappaB (NF-kappaB) binding site in the COX-2 promoter was mutated, suggesting that C/EBPbeta and NF-kappaB transcription factors have an important role in aberrant expression of COX-2 in these lung cancer cells. In addition, the eight herbal mixture PC-SPES (Lot. 5431219) caused growth arrest and apoptosis of NCI-H520 and NCI-H460 cells in association with blockade of NF-kappaB and down-regulation of C/EBPbeta, resulting in down-regulation of COX-2 and PGE2 in these cells. On the other hand, PC-SPES up-regulated the level of C/EBPbeta in these cells. Taken together, C/EBPbeta and NF-kappaB may be promising molecular targets for COX-2 inhibition in lung cancer cells. PC-SPES might be useful in the adjuvant setting for the treatment of individuals with resected NSCLC as well as other types of cancer in which COX-2 is activated. Integrin alpha11 (ITGA11/alpha11) is localized to stromal fibroblasts and commonly overexpressed in non-small-cell lung carcinoma (NSCLC). We hypothesized that stromal alpha11 could be important for the tumorigenicity of NSCLC cells. SV40 immortalized mouse embryonic fibroblasts established from wild-type (WT) and Itga11-deficient [knockout (KO)] mice were tested for their tumorigenicity in immune-deficient mice when implanted alone or coimplanted with the A549 human lung adenocarcinoma cells. A549 coimplanted with the fibroblasts showed a markedly enhanced tumor growth rate compared with A549, WT, or KO, which alone formed only small tumors. Importantly, the growth was significantly greater for A549+WT compared with A549+KO tumors. Reexpression of human alpha11 cDNA in KO cells rescued a tumor growth rate to that comparable with the A549+WT tumors. These findings were validated in two other NSCLC cell lines, NCI-H460 and NCI-H520. Gene expression profiling indicated that IGF2 mRNA expression level was >200 times lower in A549+KO compared with A549+WT tumors. Stable short-hairpin RNA (shRNA) down-regulation of IGF2 in WT (WT(shIGF2)) fibroblasts resulted in a decreased growth rate of A549+WT(shIGF2), compared with A549+WT tumors. The results indicate that alpha11 is an important stromal factor in NSCLC and propose a paradigm for carcinoma-stromal interaction indirectly through interaction between the matrix collagen and stromal fibroblasts to stimulate cancer cell growth. BHLHB3 is a basic helix-loop-helix (bHLH) domain-containing protein that acts as a transcriptional repressor. We found that BHLHB3 transcript levels were low in three human lung cancer cell lines and downregulated in human lung adenocarcinomas as compared to normal lung tissue. BHLHB3 gene overexpression inhibited colony formation of A549, NCI-H520 and NCI-H596 lung cancer cells. The reduced colony growth was likely due to inhibition of cell proliferation as suggested by the downregulation of cyclin D1 (CCND1) expression in NCI-H520 cells transfected to overexpress the BHLHB3 gene; no evidence of apoptosis was observed. These results point to the potential role of the BHLHB3 protein as a tumor suppressor for lung cancer. Starting from d- or l-tryptophan, we have synthesized and characterized six compounds 2.29-2.31a and b that belong to a class of nitrogen heterocycles: the carboline-based homodimers. Each individual homodimer features a 1,3-trans relationship on each side of the central diketopiperazine core, but differs in absolute stereochemistry and also in substitution on the 4' and 4'' oxygens (-Bn, -CH(3), or -H). The in vitro cytotoxicity of the six compounds was evaluated by measuring the growth inhibition in NCI-H520 and PC-3 human carcinoma cells. Phenol 2.30a inhibited cancer cell growth approximately three times better than its etiomer 2.30b and possessed a GI(50) comparable to the clinically used agent etoposide in both cell lines. We have concluded that both the stereochemistry imparted by l-tryptophan and the presence of hydroxy substituents at the 4' and 4'' positions are necessary to generate cytotoxic properties in the homodimer class. We are now employing 2.30a as a new lead compound in our efforts to discover improved indole-based cancer chemotherapeutics. This study investigates the anticancer effect of dehydrocostuslactone (DHE), a medicinal plant-derived sesquiterpene lactone, on human non-small cell lung cancer cell lines, A549, NCI-H460 and NCI-H520. Our results show that DHE inhibits the proliferation of A549, NCI-H460 and NCI-H520 cells. DHE-induced apoptosis in both A549 and NCI-H460 cells. DHE triggered endoplasmic reticulum (ER) stress, as indicated by changes in cytosol-calcium levels, PKR-like ER kinase (PERK) phosphorylation, inositol requiring protein 1 (IRE1) and CHOP/GADD153 upregulation, X-box transcription factor-1 (XBP-1) mRNA splicing, and caspase-4 activation. The release of calcium triggered the production of ROS, which further enhances calcium overloading and subsequently activates p38, JNK and ERK1/2. Both IRE1 miRNA transfection and BAPTA-AM pretreatment inhibit DHE-mediated apoptosis, supporting the hypothesis that DHE induces cell death through ER stress. Importantly, a novel anticancer agent for the treatment of non-small cell lung cancer, and is supported by animal studies which have shown a dramatic 50% reduction in tumor size after 28 days of treatment. This study demonstrates that DHE may be a novel anticancer agent for the treatment of non-small cell lung cancer. We report the radiosynthesis and evaluation of 3-[3,5-dimethyl-4-(4-[11C]methylpiperazinecarbonyl)-1H-pyrrol-2-ylmethylene]-2-oxo-2,3-dihydro-1H-indole-5-sulfonic acid (3-chlorophenyl)methylamide, termed [11C]SU11274 ([11C]14) for in vivo imaging of mesenchymal-epithelial transition (MET) receptor by positron emission tomography (PET). Following the synthesis of the precursor (13) that was achieved in 10 steps with a total yield of 9.7%, [11C]14 was obtained through radiomethylation in a range of 5-10% radiochemical yield and over 95% radiochemical purity. For in vivo PET studies, two human lung cancer xenograft models were established using MET-positive NCI-H1975 and MET-negative NCI-H520 cell lines. Quantitative [11C]14-PET studies showed that the tumor uptake of [11C]14 in the NCI-H1975 xenografts was significantly higher than that in the NCI-H520 xenografts, which is consistent with their corresponding immunohistochemical tissue staining patterns of MET receptors from the same animals. These studies demonstrated that [11C]14-PET is an appropriate imaging marker for quantification of MET receptor in vivo, which can facilitate efficacy evaluation in the clinical development of MET-targeted cancer therapeutics. Non-small cell lung carcinomas (NSCLC) overexpress the Her2/neu gene in approximately 59% of cases. Trastuzumab, a humanized monoclonal antibody, interferes with Her2 signaling and is approved for the treatment of Her2/neu overexpressing breast cancer. However, its therapeutic use in Her2/neu overexpressing NSCLC remains obscure. The present study aimed to determine the role of (64)Cu-labeled trastuzumab positron emission tomography (PET) for non-invasive imaging of Her2/neu expression in NSCLC. Trastuzumab was conjugated with the bifunctional chelator 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA) and radiolabeled with (64)Cu. The molecular specificity of DOTA-trastuzumab was determined in NSCLC cell lines with Her2/neu overexpression (NCI-H2170) and negative expression (NCI-H520). Imaging of Her2/neu expression was performed in NCI-H2170 tumor-bearing mice with (64)Cu-DOTA-trastuzumab PET and (64)Cu-DOTA-IgG. In vitro studies revealed specific binding of DOTA-trastuzumab in the Her2/neu positive NCI-H2170 cells, while no binding was seen in the Her2/neu negative NCI-H520 cell line. Biodistribution and PET studies revealed a significantly high accumulation of (64)Cu-DOTA-trastuzumab in the Her2/neu overexpressing NCI-H2170 tumor at 24 and 48 h post-injection (21.4 +/- 1.4% and 23.2 +/- 5.1% injection dose/gram (% ID/g), respectively). PET imaging of Her2/neu negative NCI-H520 tumors showed much less uptake of (64)Cu-DOTA-trastuzumab (4.0% ID/g). The NCI-H2170 tumor uptake of (64)Cu-DOTA-trastuzumab was significantly higher than that of (64)Cu-DOTA-IgG (P < 0.0001). (64)Cu-DOTA-trastuzumab showed a very clear image of a Her2/neu positive tumor and appeared to be effective as a PET tracer for imaging of Her2/neu gene expression in NSCLC, suggesting its potential clinical use for identifying patients that might benefit from trastuzumab-based therapy. Aminoacyl-tRNA synthetases [ARS]-interacting multifunctional protein 2 (AIMP2) has been implicated in the control of cell fate and lung cell differentiation. A variant of AIMP2 lacking exon 2 (AIMP2-DX2) is expressed in different cancer cells. We previously studied the expression level of AIMP2-DX2 in several lung cell lines and reported elevated expression levels of AIMP2-DX2 in NCI-H460 and NCI-H520. Here, we report that the suppression of AIMP2-DX2 by lentivirus mediated short hairpin (sh)RNA (sh-DX2) decreased the rate of glucose uptake and glucose transporters (Gluts) in NCI-H460 cells. Down-regulation of AIMP2-DX2 reduced glycosyltransferase (GnT)-V in the Golgi apparatus, while inducing the GnT-V antagonist GnT-III. Down-regulation of AIMP2-DX2 also suppressed the epidermal growth factor receptor/mitogen activated protein kinase (EGFR/MAPK) signaling pathway, leading to the decrease of the proliferation marker Ki-67 expression in nuclei. Furthermore, dual luciferase activity reduced capdependent protein translation in cells infected with sh-DX2. These results suggest that AIMP2-DX2 may be a relevant therapeutic target for lung cancer, and that the sh-DX2 lentiviral system can be an appropriate method for lung cancer therapy. BACKGROUND: Multidrug resistance (MDR) is a main reason for paclitaxel (TAX) treatment failure. Indirubin-3'-monoxime (IRO) and Matrine are traditional Chinese medicines, which may reverse the resistance of tumor cells to some chemotherapy drugs, but the relationship between paclitaxel resistance and Matrine is still unclear. The aim of this study was to explore the potential molecular mechanism of IRO and Matrine in reversal of TAX resistance. METHODS: In this study, MTT assay was used to measure the non-cytotoxic dosage of IRO and Matrine on NCI-H520/TAX25 cells and determine the reversal extent of TAX resistance under non-toxic doses. In addition, RT-PCR and Western blotting were used to evaluate the mRNA expression and the protein level of survivin, Oct-4, and Sox-2 in NCI-H520/TAX25 cells using semi-quantitative methods. RESULTS: There was no obvious inhibition on sensitive cell strains and drug-resistant strains, when the final concentration was at lest 4 µmol/L for IRO and 100 µmol/L for Matrine. So 4 µmol/L of IRO and 100 µmol/L of Matrine were considered as the reversal dosage. When 4 µmol/L of IRO or 100 µmol/L of Matrine were used together with TAX, the sensitivity to TAX increased evidently in NCI-H520/TAX2 cells; the reversal rate of IRO and Matrine was about 1.92 (43.56/22.6 nmol/L) and 1.74 (43.56/25.0 nmol/L), respectively. The mRNA expression and the protein level of survivin, Oct-4, and Sox-2 in NCI-H520/TAX25 decreased significantly (P < 0.05) after addition of IRO or Matrine in TAX treatment, compared to that of TAX treatment alone. CONCLUSION: The decrease in both mRNA expression and protein level of survivin, Oct-4, and Sox-2 might be the molecular mechanism, by which IRO and Matrine mediate the reversal of TAX resistance. Lung cancer is the leading cause of cancer death worldwide. Its early detection is of paramount importance for diagnosis, classification, treatment, and improvement of survivorship. However, current methods are not sensitive enough to detect lung cancer in its nascent stage. We reported an aptamer-Ag-Au shell-core ostructure-based surface-enhanced Raman scattering (SERS) assay for sensitive and specific detection, and near-infrared (NIR) photothermal therapy of lung adenocarcinoma cells (A549 cells). The ostructures target the cells with high affinity and specificity via the specific interaction between the aptamer (a 45-base oligonucleotide) and the cell, and distinguish A549 cells from other types of cancer cells (HeLa and MCF-7 cells) and subtypes of lung cancer cells (NCI-H157, NCI-H520, NCI-H1299, and NCI-H446 cells). The ostructures have a high capability to absorb NIR irradiation and are able to perform photothermal therapy of the cells at a very low irradiation power density (0.20 W cm(-2)) without destroying the healthy cells and the surrounding normal tissues. In addition, the ostructures exhibit a high SERS activity. Based on the SERS signal of the labeled Raman reporter (Rh6G molecules), we can specifically detect A549 cells at a very low abundance (~10 cells per mL) and monitor the therapy process of the cancer cells. Therefore, this ostructure-based SERS assay has great potential in specific recognition, sensitive detection, and effective photothermal therapy of lung cancer.

Have mutations in the Polycomb group been found in human diseases?

Yes, different members of the Polycomb family have been found mutated in diseases such as primary microcephaly, nonsyndromic cleft lip and several cancers (including hemotopoietic malignancies, esophageal carcinoma, head and neck cancer or prostate cancer). Exact anser: Yes

Endometrial stromal sarcomas (ESS) represent <10% of all uterine sarcomas. Cytogenetic data on this tumor type are limited to 32 cases, and the karyotypes are often complex, but the pattern of rearrangement is nevertheless clearly nonrandom with particularly frequent involvement of chromosome arms 6p and 7p. Recently, a specific translocation t(7;17)(p15;q21) leading to the fusion of two zinc finger genes, juxtaposed with another zinc finger (JAZF1) and joined to JAZF1 (JJAZ1), was described in a subset of ESS. We present three ESS whose karyotypes were without the disease-specific t(7;17) but instead showed rearrangement of chromosomal band 6p21, twice as an unbalanced t(6p;7p) and once as a three-way 6;10;10 translocation. All three tumors showed specific rearrangement of the PHD finger protein 1 (PHF1) gene, located in chromosomal band 6p21. In the two tumors with t(6;7), PHF1 was recombined with the JAZF1 gene from 7p15, leading to the formation of a JAZF1/PHF1 fusion gene. The third tumor showed a t(6p;10q;10p) as the sole karyotypic abnormality, leading to the fusion of PHF1 with another partner, the enhancer of polycomb (EPC1) gene from 10p11; EPC1 has hitherto not been associated with neoplasia. The PHF1 gene encodes a protein with two zinc finger motifs whose involvement in tumorigenesis and/or tumor progression has not been reported before, but its rearrangement clearly defines a new pathogenetic subgroup of ESS. Overexpression of the polycomb group protein enhancer of zeste homologue 2 (EZH2) has been found in several maligcies, including prostate cancer, with an aggressive phenotype. Amplification of the gene has previously been demonstrated in several maligcies, but not in prostate cancer. Our goal was to evaluate the gene copy number and expression alterations of EZH2 in prostate cancer. The copy number of EZH2 in cell lines (LNCaP, DU145, PC-3, 22Rv1), xenografts (n = 10), and clinical tumors (n = 191) was studied with fluorescence in situ hybridization. All cell lines had a gain of EZH2. Eight of the ten xenografts showed an increased copy number of the gene, including one case of high-level amplification (>or=5 copies of the gene and EZH2/centromere ratio >or=2). 34/125 (27%) of untreated prostate carcinomas showed increased copy number, but only one case of low-level amplification (>or=5 copies of the gene and EZH2/centromere ratio <2), whereas half (25/46) of the hormone-refractory carcinomas showed increased copy number, including seven cases of low-level amplification and three cases of high-level amplification (P < 0.0001). Expression of EZH2 was significantly (P = 0.0009) higher in hormone-refractory prostate cancer compared with that in benign prostatic hyperplasia or untreated cancer, according to quantitative real-time RT-PCR assay. Also, the expression of EZH2 protein was found to be higher in hormone-refractory tumors than in hormone-naïve tumors by immunohistochemistry. The EZH2 gene amplification was significantly (P < 0.05) associated with increased EZH2 protein expression. The data show that amplification of the EZH2 gene is rare in early prostate cancer, whereas a fraction of late-stage tumors contains the gene amplification leading to the overexpression of the gene, thus indicating the importance of EZH2 in the progression of prostate cancer. The Polycomb group (PcG) gene BMI1 is required for the proliferation and self-renewal of normal and leukemic stem cells. Overexpression of Bmi1 oncogene causes neoplastic transformation of lymphocytes and plays essential role in pathogenesis of myeloid leukemia. Another PcG protein, Ezh2, was implicated in metastatic prostate and breast cancers, suggesting that PcG pathway activation is relevant for epithelial maligcies. Whether an oncogenic role of the BMI1 and PcG pathway activation may be extended beyond the leukemia and may affect progression of solid tumors as well remains unknown. Here we demonstrate that activation of the BMI1 oncogene-associated PcG pathway plays an essential role in metastatic prostate cancer, thus mechanistically linking the pathogenesis of leukemia, self-renewal of stem cells, and prostate cancer metastasis. To characterize the functional status of the PcG pathway in metastatic prostate cancer, we utilized advanced cell- and whole animal-imaging technologies, gene and protein expression profiling, stable siRNA-gene targeting, and tissue microarray (TMA) analysis in relevant experimental and clinical settings. We demonstrate that in multiple experimental models of metastatic prostate cancer both BMI1 and Ezh2 genes are amplified and gene amplification is associated with increased expression of corresponding mRNAs and proteins. For the first time, we provide images of human prostate carcinoma metastasis precursor cells isolated from blood and shown to overexpress both BMI1 and Ezh2 oncoproteins. Consistent with the PcG pathway activation hypothesis, increased BMI1 and Ezh2 expression in metastatic cancer cells is associated with elevated levels of H2AubiK119 and H3metK27 histones. Quantitative immunofluorescence colocalization analysis and expression profiling experiments documented increased BMI1 and Ezh2 expression in clinical prostate carcinoma samples and demonstrated that high levels of BMI1 and Ezh2 expression are associated with markedly increased likelihood of therapy failure and disease relapse after radical prostatectomy. Gene-silencing analysis reveals that activation of the PcG pathway is mechanistically linked with highly maligt behavior of human prostate carcinoma cells and is essential for in vivo growth and metastasis of human prostate cancer. We conclude that the results of experimental and clinical analyses indicate the important biological role of the PcG pathway activation in metastatic prostate cancer. Our work suggests that the PcG pathway activation is a common oncogenic event in pathogenesis of metastatic solid tumors and provides justification for development of small molecule inhibitors of the PcG chromatin silencing pathway as a novel therapeutic modality for treatment of metastatic prostate cancer. Deregulated HOX expression, by chromosomal translocations and myeloid-lymphoid leukemia (MLL) rearrangements, is causal in some types of leukemia. Using real-time reverse transcription-PCR, we examined the expression of 43 clustered HOX, polycomb, MLL and FLT3 genes in 119 newly diagnosed adult acute myeloid leukemias (AMLs) selected from all major cytogenetic groups. Downregulated HOX expression was a consistent feature of favorable AMLs and, among these cases, inv(16) cases had a distinct expression profile. Using a 17-gene predictor in 44 additional samples, we observed a 94.7% specificity for classifying favorable vs intermediate/unfavorable cytogenetic groups. Among other AMLs, HOX overexpression was associated with nucleophosmin (NPM) mutations and we also identified a phenotypically similar subset with wt-NPM. In many unfavorable and other intermediate cytogenetic AMLs, HOX levels resembled those in normal CD34+ cells, except that the homogeneity characteristic of normal samples was not present. We also observed that HOXA9 levels were significantly inversely correlated with survival and that BMI-1 was overexpressed in cases with 11q23 rearrangements, suggesting that p19(ARF) suppression may be involved in MLL-associated leukemia. These results underscore the close relationship between HOX expression patterns and certain forms of AML and emphasize the need to determine whether these differences play a role in the disease process. Nonsyndromic cleft lip with or without cleft palate (CL/P) affects approximately 1 in 1,000 births. Genetic studies have provided evidence for the role of several genes and candidate loci in clefting; however, conflicting results have frequently been obtained and much have to be done to unravel the complex genetics of CL/P. In the present investigation we have focused on the candidate region in 6p23, a region that have been found linked to CL/P in several investigations, in the attempt to find out the susceptibility gene provisionally named OFC1. Gene expression experiments in mice embryo of positional candidate genes revealed that JARID2 was highly and specifically expressed in epithelial cells in merging palatal shelves. A family-based linkage disequilibrium study confirmed the pivotal role of JARID2 in orofacial development and strongly supports a role for this gene in CL/P etiology (multiallelic haplotype test P=6 x 10(-5)). Understanding the molecular role of JARID2 within facial development may offer additional information to further unravel the complex genetics of CL/P. We genotyped 370 subjects with primary myelofibrosis (PMF) and 148 with postpolycythemia vera/postessential thrombocythemia (PPV/PET) MF for mutations of EZH2. Mutational status at diagnosis was correlated with hematologic parameters, clinical manifestations, and outcome. A total of 25 different EZH2 mutations were detected in 5.9% of PMF, 1.2% of PPV-MF, and 9.4% of PET-MF patients; most were exonic heterozygous missense changes. EZH2 mutation coexisted with JAK2V617F or ASXL1 mutation in 12 of 29 (41.4%) and 6 of 27 (22.2%) evaluated patients; TET2 and CBL mutations were found in 2 and 1 patients, respectively. EZH2-mutated PMF patients had significantly higher leukocyte counts, blast-cell counts, and larger spleens at diagnosis, and most of them (52.6%) were in the high-risk International Prognostic Score System (IPSS) category. After a median follow-up of 39 months, 128 patients (25.9%) died, 81 (63.3%) because of leukemia. Leukemia-free survival (LFS) and overall survival (OS) were significantly reduced in EZH2-mutated PMF patients (P = .028 and P < .001, respectively); no such impact was seen for PPV/PET-MF patients, possibly due to the low number of mutated cases. In multivariate analysis, survival of PMF patients was predicted by IPSS high-risk category, a < 25% JAK2V617F allele burden, and EZH2 mutation status. We conclude that EZH2 mutations are independently associated with shorter survival in patients with PMF. Chronic myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS) have an inherent tendency to progress to acute myeloid leukemia (AML). Using high-resolution SNP microarrays, we studied a total of 517 MPN and MDS patients in different disease stages, including 77 AML cases with previous history of MPN (N = 46) or MDS (N = 31). Frequent chromosomal deletions of variable sizes were detected, allowing the mapping of putative tumor suppressor genes involved in the leukemic transformation process. We detected frequent deletions on the short arm of chromosome 6 (del6p). The common deleted region on 6p mapped to a 1.1-Mb region and contained only the JARID2 gene--member of the polycomb repressive complex 2 (PRC2). When we compared the frequency of del6p between chronic and leukemic phase, we observed a strong association of del6p with leukemic transformation (P = 0.0033). Subsequently, analysis of deletion profiles of other PRC2 members revealed frequent losses of genes such as EZH2, AEBP2, and SUZ12; however, the deletions targeting these genes were large. We also identified two patients with homozygous losses of JARID2 and AEBP2. We observed frequent codeletion of AEBP2 and ETV6, and similarly, SUZ12 and NF1. Using next generation exome sequencing of 40 patients, we identified only one somatic mutation in the PRC2 complex member SUZ12. As the frequency of point mutations in PRC2 members was found to be low, deletions were the main type of lesions targeting PRC2 complex members. Our study suggests an essential role of the PRC2 complex in the leukemic transformation of chronic myeloid disorders. T cell acute lymphoblastic leukemia (T-ALL) is an immature hematopoietic maligcy driven mainly by oncogenic activation of NOTCH1 signaling. In this study we report the presence of loss-of-function mutations and deletions of the EZH2 and SUZ12 genes, which encode crucial components of the Polycomb repressive complex 2 (PRC2), in 25% of T-ALLs. To further study the role of PRC2 in T-ALL, we used NOTCH1-dependent mouse models of the disease, as well as human T-ALL samples, and combined locus-specific and global analysis of NOTCH1-driven epigenetic changes. These studies demonstrated that activation of NOTCH1 specifically induces loss of the repressive mark Lys27 trimethylation of histone 3 (H3K27me3) by antagonizing the activity of PRC2. These studies suggest a tumor suppressor role for PRC2 in human leukemia and suggest a hitherto unrecognized dynamic interplay between oncogenic NOTCH1 and PRC2 function for the regulation of gene expression and cell transformation. Chronic myelomonocytic leukemia (CMML) has recently been associated with a high incidence of diverse mutations in genes such as TET2 or EZH2 that are implicated in epigenetic mechanisms. We have performed genome-wide DNA methylation arrays and mutational analysis of TET2, IDH1, IDH2, EZH2 and JAK2 in a group of 24 patients with CMML. 249 genes were differentially methylated between CMML patients and controls. Using Ingenuity pathway analysis, we identified enrichment in a gene network centered around PLC, JNK and ERK suggesting that these pathways, whose deregulation has been recently described in CMML, are affected by epigenetic mechanisms. Mutations of TET2, JAK2 and EZH2 were found in 15 patients (65%), 4 patients (17%) and 1 patient (4%) respectively while no mutations in the IDH1 and IDH2 genes were identified. Interestingly, patients with wild type TET2 clustered separately from patients with TET2 mutations, showed a higher degree of hypermethylation and were associated with higher risk karyotypes. Our results demonstrate the presence of aberrant DNA methylation in CMML and identifies TET2 mutant CMML as a biologically distinct disease subtype with a different epigenetic profile. In this study, we show the high frequency of spontaneous γδ T-cell leukemia (T-ALL) occurrence in mice with biallelic deletion of enhancer of zeste homolog 2 (Ezh2). Tumor cells show little residual H3K27 trimethylation marks compared with controls. EZH2 is a component of the PRC2 Polycomb group protein complex, which is associated with DNA methyltransferases. Using next-generation sequencing, we identify alteration in gene expression levels of EZH2 and acquired mutations in PRC2-associated genes (DNMT3A and JARID2) in human adult T-ALL. Together, these studies document that deregulation of EZH2 and associated genes leads to the development of mouse, and likely human, T-ALL. PURPOSE: A subset of patients with myelodysplastic syndromes (MDS) who are predicted to have lower-risk disease as defined by the International Prognostic Scoring System (IPSS) demonstrate more aggressive disease and shorter overall survival than expected. The identification of patients with greater-than-predicted prognostic risk could influence the selection of therapy and improve the care of patients with lower-risk MDS. PATIENTS AND METHODS: We performed an independent validation of the MD Anderson Lower-Risk Prognostic Scoring System (LR-PSS) in a cohort of 288 patients with low- or intermediate-1 IPSS risk MDS and examined bone marrow samples from these patients for mutations in 22 genes, including SF3B1, SRSF2, U2AF1, and DNMT3A. RESULTS: The LR-PSS successfully stratified patients with lower-risk MDS into three risk categories with significant differences in overall survival (20% in category 1 with median of 5.19 years [95% CI, 3.01 to 10.34 years], 56% in category 2 with median of 2.65 years [95% CI, 2.18 to 3.30 years], and 25% in category 3 with median of 1.11 years [95% CI, 0.82 to 1.51 years]), thus validating this prognostic model. Mutations were identified in 71% of all samples, and mutations associated with a poor prognosis were enriched in the highest-risk LR-PSS category. Mutations of EZH2, RUNX1, TP53, and ASXL1 were associated with shorter overall survival independent of the LR-PSS. Only EZH2 mutations retained prognostic significance in a multivariable model that included LR-PSS and other mutations (hazard ratio, 2.90; 95% CI, 1.85 to 4.52). CONCLUSION: Combining the LR-PSS and EZH2 mutation status identifies 29% of patients with lower-risk MDS with a worse-than-expected prognosis. These patients may benefit from earlier initiation of disease-modifying therapy. Chromosomal instability (CIN) is widely considered a hallmark of cancer, but its precise roles in cancer stem cells (CSC) and maligt progression remain uncertain. BMI1 is a member of the Polycomb group of chromatin-modifier proteins that is essential for stem cell self-renewal. In human cancers, BMI1 overexpression drives stem-like properties associated with induction of epithelial-mesenchymal transition (EMT) that promotes invasion, metastasis, and poor prognosis. Here, we report that BMI1 mediates its diverse effects through upregulation of the mitotic kinase Aurora A, which is encoded by the AURKA gene. Two mechanisms were found to be responsible for BMI1-induced AURKA expression. First, BMI1 activated the Akt pathway, thereby upregulating AURKA expression through activation of the β-catenin/TCF4 transcription factor complex. Second, BMI1 repressed miRNA let-7i through a Polycomb complex-dependent mechanism, thereby relieving AURKA expression from let-7i suppression. AURKA upregulation by BMI1 exerts several effects, including centrosomal amplification and aneuploidy, antiapoptosis, and cell-cycle progression through p53 degradation and EMT through stabilization of Snail. Inhibiting Aurora A kinase activity attenuated BMI1-induced tumor growth in vivo. In clinical specimens of head and neck cancer, we found that coamplification of BMI1 and AURKA correlated with poorer prognosis. Together, our results link CSCs, EMT, and CIN through the BMI1-AURKA axis and suggest therapeutic use from inhibiting Aurora A in head and neck cancers, which overexpress BMI1. Primary microcephaly (PM) is a developmental disorder of early neuroprogenitors that results in reduction of the brain mass, particularly the cortex. To gain fresh insight into the pathogenesis of PM, we describe a consanguineous family with a novel genetic variant responsible for the disease. We performed autozygosity mapping followed by exome sequencing to detect the causal genetic variant. Several functional assays in cells expressing the wild-type or mutant gene were performed to understand the pathogenesis of the identified mutation. We identify a novel mutation in PHC1, a human orthologue of the Drosophila polyhomeotic member of polycomb group (PcG), which significantly decreases PHC1 protein expression, increases Geminin protein level and markedly abolishes the capacity to ubiquitinate histone H2A in patient cells. PHC1 depletion in control cells similarly enhances Geminin expression and decreases histone H2A ubiquitination. The ubiquitination defect and accumulation of Geminin with consequent defect in cell cycle are rescued by over-expression of PHC1 in patient cells. Although patients with the PHC1 mutation exhibit PM with no overt progression of the disease, patient cells also show aberrant DNA damage repair, which is rescued by PHC1 overexpression. These findings reveal several cellular defects in cells carrying the PHC1 mutation and highlight the role of chromatin remodeling in the pathogenesis of PM.

Describe the mechanism of action of drisapersen

Drisapersen is a 2'-O-methyl-phosphorothioate oligonucleotide designed to skip exon 51 in dystrophin pre-mRNA to restore the reading frame of the mRNA. It has potential for treatment of Duchenne muscular dystrophy.

PURPOSE OF REVIEW: The most encouraging recent advances regarding pharmacological agents for treating Duchenne muscular dystrophy (DMD) are summarized. Emphasis is given to compounds acting downstream of dystrophin, the protein lacking in DMD, on cellular pathways leading to pathological consequences. The author highlights the progress that may have the greatest potential for clinical use in DMD. RECENT FINDINGS: Modifying the transcripts of the mutated gene by exon skipping has led to expression of shortened dystrophins in DMD patients. Currently, the most promising potential drugs are the exon-skipping agents eteplirsen and drisapersen. Biglycan and SMTC1100 upregulate utrophin. The steroid receptor modulating compounds VBP15 and tamoxifen, and specific antioxidants appear promising agents for symptomatic therapy. SUMMARY: The past 18 months have seen a strong increase in the number of exciting reports on novel therapeutic agents for DMD. Exon-skipping agents have been fine-tuned to improve tissue delivery and stability. Impressive discoveries regarding pathogenic events in cellular signalling have revealed targets that were unknown in the context of DMD, thus enabling approaches that limit inflammation, fibrosis and necrosis. The targets are nuclear hormone receptors, NADPH-oxidases and Ca channels. Inhibition of NF-KB, transforming growth factor-alpha (TGF-α) and transforming growth factor-beta (TGF-β)/myostatin production or action are also promising routes in counteracting the complex pathogenesis of DMD. Chronic administration of drisapersen, a 2'-OMe phosphorothioate antisense oligonucleotide (AON) to mice and monkeys resulted in renal tubular accumulation, with secondary tubular degeneration. Glomerulopathy occurred in both species with species-specific characteristics. Glomerular lesions in mice were characterized by progressive hyaline matrix accumulation, accompanied by the presence of renal amyloid and with subsequent papillary necrosis. Early changes involved glomerular endothelial hypertrophy and degeneration, but the chronic glomerular amyloid and hyaline alterations in mice appeared to be species specific. An immune-mediated mechanism for the glomerular lesions in mice was supported by early inflammatory changes including increased expression of inflammatory cytokines and other immunomodulatory genes within the renal cortex, increased stimulation of CD68 protein, and systemic elevation of monocyte chemotactic protein 1. In contrast, kidneys from monkeys given drisapersen chronically showed less severe glomerular changes characterized by increased mesangial and inflammatory cells, endothelial cell hypertrophy, and subepithelial and membranous electron-dense deposits, with ultrastructural and immunohistochemical characteristics of complement and complement-related fragments. Lesions in monkeys resembled typical features of C3 glomerulopathy, a condition described in man and experimental animals to be linked to dysregulation of the alternative complement pathway. Thus, inflammatory/immune mechanisms appear critical to glomerular injury with species-specific sensitivities for mouse and monkey. The lower observed proinflammatory activity in humans as compared to mice and monkeys may reflect a lower risk of glomerular injury in patients receiving AON therapy. Duchenne muscular dystrophy (DMD) is a progressive, lethal neuromuscular disorder caused by the absence of dystrophin protein due to mutations of the dystrophin gene. Drisapersen is a 2'-O-methyl-phosphorothioate oligonucleotide designed to skip exon 51 in dystrophin pre-mRNA to restore the reading frame of the mRNA. This study assessed safety, tolerability, and pharmacokinetics of drisapersen after a single subcutaneous administration in non-ambulatory subjects. Eligible subjects were non-ambulant boys aged ⩾9years, in wheelchairs for ⩾1 to ⩽4years, with a diagnosis of DMD resulting from a mutation correctable by drisapersen treatment. Four dose cohorts were planned (3, 6, 9 and 12mg/kg), but study objectives were met with the 9mg/kg dose. Less than proportional increase in exposure was demonstrated over the 3-9mg/kg dose range, though post hoc analysis showed dose proportionality was more feasible over the 3-6mg/kg range. Single doses of drisapersen at 3 and 6mg/kg did not result in significant safety or tolerability concerns; however, at the 9mg/kg dose, pyrexia and transient elevations in inflammatory parameters were seen. The maximum tolerated dose of 6mg/kg drisapersen was identified for further characterization in multiple dose studies in the non-ambulant DMD population. BACKGROUND: Duchenne muscular dystrophy is caused by dystrophin deficiency and muscle deterioration and preferentially affects boys. Antisense-oligonucleotide-induced exon skipping allows synthesis of partially functional dystrophin. We investigated the efficacy and safety of drisapersen, a 2'-O-methyl-phosphorothioate antisense oligonucleotide, given for 48 weeks. METHODS: In this exploratory, double-blind, placebo-controlled study we recruited male patients (≥5 years of age; time to rise from floor ≤7 s) with Duchenne muscular dystrophy from 13 specialist centres in nine countries between Sept 1, 2010, and Sept 12, 2012. By use of a computer-generated randomisation sequence, we randomly allocated patients (2:2:1:1; block size of six; no stratification) to drisapersen 6 mg/kg or placebo, each given subcutaneously and either continuously (once weekly) or intermittently (nine doses over 10 weeks). The primary endpoint was change in 6-min walk distance (6MWD) at week 25 in patients in the intention-to-treat population for whom data were available. Safety assessments included renal, hepatic, and haematological monitoring and recording of adverse events. This trial is registered with ClinicalTrials.gov, number NCT01153932. FINDINGS: We recruited 53 patients: 18 were given continuous drisapersen, 17 were given intermittent drisapersen, and 18 were given placebo (continuous and intermittent groups combined). At week 25, mean 6MWD had increased by 31·5 m (SE 9·8) from baseline for continuous drisapersen, with a mean difference in change from baseline of 35·09 m (95% CI 7·59 to 62·60; p=0·014) versus placebo. We recorded no difference in 6MWD changes from baseline between intermittent drisapersen (mean change -0·1 [SE 10·3]) and placebo (mean difference 3·51 m [-24·34 to 31·35]) at week 25. The most common adverse events in drisapersen-treated patients were injection-site reactions (14 patients given continuous drisapersen, 15 patients given intermittent drisapersen, and six given placebo) and renal events (13 for continuous drisapersen, 12 for intermittent drisapersen, and seven for placebo), most of which were subclinical proteinuria. None of the serious adverse events reported (one for continuous, two for intermittent, and two for placebo) resulted in withdrawal from the study. INTERPRETATION: Continuous drisapersen resulted in some benefit in 6MWD versus placebo at week 25. The safety findings are similar to those from previous studies. Ambulation improvements in this young population with early-stage Duchenne muscular dystrophy are encouraging but need to be confirmed in larger studies. FUNDING: GlaxoSmithKline, Prosensa Therapeutics BV (a subsidiary of Prosensa Holding NV).

Is microRNA(miRNA) 29 involved in post-ischemic cardiac remodeling?

miRNA 29 is involved in post-ischemic myocardial remodeling in particular in the peri-infarctual zone. miRNA 29 produces apoptosis and enhances fibrotic response.

BACKGROUND: Hemodynamic load regulates myocardial function and gene expression. We tested the hypothesis that afterload and preload, despite similar average load, result in different phenotypes. METHODS AND RESULTS: Afterload and preload were compared in mice with transverse aortic constriction (TAC) and aortocaval shunt (shunt). Compared with sham mice, 6 hours after surgery, systolic wall stress (afterload) was increased in TAC mice (+40%; P<0.05), diastolic wall stress (preload) was increased in shunt (+277%; P<0.05) and TAC mice (+74%; P<0.05), and mean total wall stress was similarly increased in TAC (69%) and shunt mice (67%) (P=NS, TAC versus shunt; each P<0.05 versus sham). At 1 week, left ventricular weight/tibia length was significantly increased by 22% in TAC and 29% in shunt mice (P=NS, TAC versus shunt). After 24 hours and 1 week, calcium/calmodulin-dependent protein kinase II signaling was increased in TAC. This resulted in altered calcium cycling, including increased L-type calcium current, calcium transients, fractional sarcoplasmic reticulum calcium release, and calcium spark frequency. In shunt mice, Akt phosphorylation was increased. TAC was associated with inflammation, fibrosis, and cardiomyocyte apoptosis. The latter was significantly reduced in calcium/calmodulin-dependent protein kinase IIdelta-knockout TAC mice. A total of 157 mRNAs and 13 microRNAs were differentially regulated in TAC versus shunt mice. After 8 weeks, fractional shortening was lower and mortality was higher in TAC versus shunt mice. CONCLUSIONS: Afterload results in maladaptive fibrotic hypertrophy with calcium/calmodulin-dependent protein kinase II-dependent altered calcium cycling and apoptosis. Preload is associated with Akt activation without fibrosis, little apoptosis, better function, and lower mortality. This indicates that different loads result in distinct phenotype differences that may require specific pharmacological interventions. MicroRNAs (miRNA) are small regulatory RNAs that control gene expression by translational suppression and destabilization of target mRNAs. There is increasing evidence that miRNAs regulate genes associated with fibrosis in organs, such as the heart, kidney, liver, and the lung. In a large-scale screening for miRNAs potentially involved in bleomycin-induced fibrosis, we found expression of miR-29 family members significantly reduced in fibrotic lungs. Analysis of normal lungs showed the presence of miR-29 in subsets of interstitial cells of the alveolar wall, pleura, and at the entrance of the alveolar duct, known sites of pulmonary fibrosis. miR-29 levels inversely correlated with the expression levels of profibrotic target genes and the severity of the fibrosis. To study the impact of miR-29 down-regulation in the lung interstitium, we characterized gene expression profiles of human fetal lung fibroblast IMR-90 cells in which endogenous miR-29 was knocked down. This confirmed the derepression of reported miR-29 targets, including several collagens, but also revealed up-regulation of a large number of previously unrecognized extracellular matrix-associated and remodeling genes. Moreover, we found that miR-29 is suppressed by transforming growth factor (TGF)-β1 in these cells, and that many fibrosis-associated genes up-regulated by TGF-β1 are derepressed by miR-29 knockdown. Interestingly, a comparison of TGF-β1 and miR-29 targets revealed that miR-29 controls an additional subset of fibrosis-related genes, including laminins and integrins, independent of TGF-β1. Together, these strongly suggest a role of miR-29 in the pathogenesis of pulmonary fibrosis. miR-29 may be a potential new therapeutic target for this disease. Myocardial ischaemia/reperfusion (I/R)-induced remodelling generally includes cell death (necrosis and apoptosis), myocyte hypertrophy, angiogenesis, cardiac fibrosis, and myocardial dysfunction. It is becoming increasingly clear that microRNAs (miRNAs or miRs), a group of highly conserved small (∼18-24 nucleotide) non-coding RNAs, fulfil specific functions in the reperfused myocardium towards post-infarct remodelling. While miR-21, -133, -150, -195, and -214 regulate cardiomyocyte hypertrophy, miR-1/-133 and miR-208 have been elucidated to influence myocardial contractile function. In addition, miR-21, -24, -133, -210, -494, and -499 appear to protect myocytes against I/R-induced apoptosis, whereas miR-1, -29, -199a, and -320 promote apoptosis. Myocardial fibrosis can be regulated by the miR-29 family and miR-21. Moreover, miR-126 and miR-210 augment I/R-induced angiogenesis, but miR-24, -92a, and -320 suppress post-infarct neoangiogenesis. In this review, we summarize the latest advances in the identification of myocardial ischaemia-associated miRNAs and their functional significance in the modulation of I/R-triggered remodelling. Controversial effects of some miRNAs in post-infarct remodelling will be also discussed.

What is the incidence of Edwards syndrom in the european population?

Between 0.125 and 39 in every 1000 live births. Most probably 1:5000 of live-born.

BACKGROUND: Maternal serum triple marker screening (alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol) can detect 60-70% of Down syndrome and 60% of Edwards syndrome. Previous studies have reported that positive serum screening is related to other fetal chromosomal abnormalities, pregcy complications, and adverse outcomes. We determined the incidence and karyotype of chromosomal abnormalities in screen positive women and evaluated a relationship between chromosomal and ultrasonographic abnormalities. METHODS: Of the 49,806 pregt women between 15 and 23 weeks' gestational age who received prenatal serum screening with a cut-off value (a risk of 1:270 for Down and 1:100 for Edwards syndrome), 2,116 (4.2%) and 196 (0.4%) were screen positive for Down syndrome and for Edwards syndrome, respectively. Chromosomal analysis in amniotic fluid was performed for 1,893 (89.5%) of the Down positive and 140 (71.4%) of the Edwards positive pregt women. Ultrasonographic examination was performed to detect fetal abnormalities. RESULTS: Eighty-three cases of chromosomal abnormalities including 40 trisomy 21 (2.1%) and 43 other chromosomal abnormalities (2.3%) were identified in the Down screen positive. Other chromosomal abnormalities included 9 numerical and 34 structural abnormalities. Ten cases of chromosomal abnormalities (9 trisomy 18 and 1 trisomy 9) were detected in the Edwards screen positive. Ultrasonographic abnormalities were found more frequently in the women who had chromosomal aberrations. CONCLUSIONS: These data suggest that 4.4% of the Down screen and 7.1% of the Edwards screen positive pregcy have fetal chromosomal abnormalities. Positive Down screening results reflect a relatively high probability of other abnormalities except trisomy 21. Edwards screen positive group show a low frequency of other chromosomal abnormalities except trisomy 18. A simultaneous use of maternal serum screening and ultrasonograms could be useful for the diagnosis of fetal abnormalities. AIM OF STUDY: An analysis of prenatal diagnostics efficiency of selected types of chromosomal aberrations in the Czech Republic in 2007. Update of 1994-2007 data according to particular selected diagnoses. TYPE OF STUDY: Retrospective epidemiological analysis of pre- and postnatal chromosomal aberrations diagnostics and its efficiency. MATERIAL AND METHODS: Data on pre- and postnatally diagnosed birth defects in the Czech Republic during 1994-2007 were used. Data on prenatally diagnosed birth defects (and for terminated pregcies) were collected from particular departments of prenatal diagnostics, medical genetics and ultrasound diagnostics in the Czech Republic, data on birth defects in births from the National Birth Defects Register (Institute for Health Information and Statistics). Total numbers over the period under the study, mean incidences of selected types of chromosomal aberrations and mean prenatal diagnostics efficiencies were analyzed. Following chromosomal aberrations were studied: Down, Edwards, Patau, Turner and Klinefelter syndromes and syndromes 47,XXX and 47,XYY. RESULTS: A relative proportion of Down, Edwards and Patau syndromes as well as other autosomal and gonosomal aberration is presented in figures. Recently, trisomies 13, 18 and 21 present around 70% of all chromosomal aberrations in selectively aborted fetuses, in other pregcies, "other chromosomal aberrations" category (mostly balanced reciprocal translocations and inversions) present more than 2/3 of all diagnoses. During the period under the study, following total numbers, mean relative incidences (per 10,000 live births, in brackets) and mean prenatal diagnostics efficiency (in %) were found in following chromosomal syndromes: Down syndrome 2,244 (16.58) and 63.37%, Edwards syndrome 521 (3.85) and 79.93%, Patau syndrome 201 (1.49) and 68.87%, Turner syndrome 380 (2.81) and 79.89%, 47,XXX syndrome 61 (0.45) and 59.74%, Klinefelter syndrome 163 (1.20) and 73.65% and 47,XYY syndrome 22 (0.16) and 54.76%. CONCLUSIONS: The study gives updated results of incidences analysis of both pre- and postnatally diagnosed chromosomal birth defects in the Czech Republic during the 1994-2007 period. Incidences found in our study correspond (in case of trisomies 13, 18 and 21) with those published widely in literature as well as with those found in large-scale international studies (ICBDSR, EUROCAT). In case of gonosomal aberrations, incidences found in this study are lower that those published, most probably due to a later registration (over 15 years of age of the child) of these diagnoses. OBJECTIVES: To determine whether older paternal age increases the risk of fathering a pregcy with Patau (trisomy 13), Edwards (trisomy 18), Klinefelter (XXY) or XYY syndrome. DESIGN: Case-control: cases with each of these syndromes were matched to four controls with Down syndrome from within the same congenital anomaly register and with maternal age within 6 months. SETTING: Data from 22 EUROCAT congenital anomaly registers in 12 European countries. PARTICIPANTS: Diagnoses with observed or (for terminations) predicted year of birth from 1980 to 2005, comprising live births, fetal deaths with gestational age ≥ 20 weeks and terminations after prenatal diagnosis of the anomaly. Data include 374 cases of Patau syndrome, 929 of Edwards syndrome, 295 of Klinefelter syndrome, 28 of XYY syndrome and 5627 controls with Down syndrome. MAIN OUTCOME MEASURES: Odds ratio (OR) associated with a 10-year increase in paternal age for each anomaly was estimated using conditional logistic regression. Results were adjusted to take account of the estimated association of paternal age with Down syndrome (1.11; 95% CI 1.01 to 1.23). RESULTS: The OR for Patau syndrome was 1.10 (95% CI 0.83 to 1.45); for Edwards syndrome, 1.15 (0.96 to 1.38); for Klinefelter syndrome, 1.35 (1.02 to 1.79); and for XYY syndrome, 1.99 (0.75 to 5.26). CONCLUSIONS: There was a statistically significant increase in the odds of Klinefelter syndrome with increasing paternal age. The larger positive associations of Klinefelter and XYY syndromes with paternal age compared with Patau and Edwards syndromes are consistent with the greater percentage of these sex chromosome anomalies being of paternal origin. Oesophageal atresia is a congenital defect of alimentary tract concerning the interruption of oesophagus with or without connection with the trachea. Its incidence is 1:3000-3500 of live-born. Associated anomalies including genetic disorders occur in 50% of patients. Edwards syndrome which is trisomy of chromosome 18 with poor prognosis. The incidence of Edwards syndrome is 1:5000 of live-born. About 5% of these children live more than 1 year. The aim of this article is a retrospective analysis of the course of treatment of newborn with oesophageal atresia and Edwards syndrome and making of therapeutic decision. The authors from different medical specializations: clinical genetics, paediatric surgery, paediatrics and neonatology, paediatric intensive care and palliative medicine, have undertaken a discussion regarding surgical treatment of children with oesophageal atresia and chromosomal, lethal syndrome. AIM OF STUDY: An analysis of incidences of selected birth defects in the Czech Republic in 2000 - 2008 period. TYPE OF STUDY: Retrospective epidemiological analysis of birth defects incidences in births and total birth defects incidences (including prenatally diagnosed cases) from the Czech National Birth Defects Register database. MATERIAL AND METHODS: Data from the National Birth Defects Register (Institute for Health Information and Statistics) in the Czech Republic in the 2000 - 2008 period were used along with data on prenatally diagnosed defects from particular departments of medical genetics. Sixteen selected defects (anencephaly, spina bifida, encephalocele, congenital hydrocephalus, coarctation of aorta, transposition of great vessels, hypoplastic left heart syndrome, Fallot tetralogy, omphalocele, gastroschisis, diaphragmatic hernia, oesophageal atresia and stenosis, anorectal malformations, Down syndrome, Edwards syndrome and Patau syndrome) were analyzed in detail. RESULTS: There were 119 570 live births (61 326 boys and 58 244 girls) in 2008. In the same period, 4664 live births with a birth defect (under the age of one year) were reported, out of which 2754 boys and 1910 girls. Mean incidence was 390.06 (449.08 in boys and 327.93 in girls) per 10 000 live births. In 1994 - 2006, totally 1 238 398 children were born, out of which more than 42 000 with a birth defect. In the 2000 - 2006 period, absolute numbers of diagnosed live births with birth defect varied between 3600 - 3800 cases per year while in 2007 and 2008 years absolute numbers raised over 4600 cases per year. During 2000 - 2008 period following mean incidences (per 10 000 live births) of selected defects were ascertained (total incidences including prenatal diagnostics in brackets): anencephaly 0 - 0.3 (1.9 - 3.7), spina bifida 0.7 - 2.3 (3.2 - 5.2), encephalocele 0.1 - 0.4 (0.9 - 2.4), congenital hydrocephalus 1.6 - 3.5 (5.3 - 7.0), coarctation of aorta 3.9 - 5.2 (4.8 - 6.1), transposition of great vessels 2.9 - 4.5 (3.2 - 5.0), hypoplastic left heart syndrome 0.7 - 2.3 (2.2 - 4.3), Fallot tetralogy 2.6 - 4.0 (3.2 - 4.4), omphalocele 1.0 - 1.7 (1.8 - 3.8), gastroschisis 0.2 - 1.2 (2.4 - 3.4), diaphragmatic hernia 1.3 - 2.9 (1.5 - 3.9), Down syndrome 3.3 - 6.5 (15.8 - 22.2), Edwards syndrome 0.2 - 1.0 (3.5 - 5.8) and Patau syndrome 0.2 - 1.0 (1.2 - 2.6). CONCLUSIONS: There has been no major change in birth defect incidences in live births in the Czech Republic in last years. Number of non-viable defects has decreased in stillbirths and in perinatal mortality in the Czech Republic. An incidence of some defects has decreased mostly due to a nation-wide system of prenatal diagnostics; some incidences remain stable in live-birth population in others incidences have increased. A total incidence has mostly increased (anencephaly being an exception) mostly due to an earlier prenatal diagnostics. In chromosomal syndromes, an increasing maternal age as well as a growing number of mothers of 35 years of age and over has contributed to the increased incidences. Edwards syndrome (trisomy 18) occurs in 1: 8000 live births and is closely related to the mother's age. Most of the embryos and fetuses with trisomy of 18 chromosome pair undergo natural abortion. Change in number and structure of chromosomes usually takes place spontaneously. However, the incidence of chromosome mutations increases with the presence of mutagenic factors. One of the chemical mutagenic factors is benzopyrene - present in cigarette smoke. Prenatal cytogenetic diagnostic is used for detecting diseases and clinical syndromes conditioned by chromosome aberrations. To this date the "golden standard" of this diagnostic is the assessment of the fetus karyotype by means of analysis of chromosome banding pattern from amniotic fluid-derived cells. The aim of the study was the analysis of indications for genetic amniocenteses carried out in the last 5 years and in case of which trisomy of chromosome 18 (Edwards syndrome) was diagnosed. The analysis covered 1593 results of fetus karyotypes obtained from Cytogenetic Laboratory of the Central Gynecological-Obstetric Clinical Hospital in Poznań over the last 5 years. The study procedure consisted in producing cell culture from amniotic fluid, appliance of appropriate color techniques and thorough microscopic analysis of chromosome banding pattern. As a result of the analysis it was discovered that in 1538 cases the karyotype was normal, and in 55 cases trisomy 18 was diagnosed, which constituted 3% of all cytogenetic tests. The highest number of trisomy 18 cases was noted in 2009 - 19 cases, which constitutes 5% of all tests. In 2010 and 2011 the results included respectively 2% and 3% of diagnosed trisomy 18 (Edwards syndrome). In the last 5 years normal results for karyotypes constituted 87%, in 10% cases other aberrations were diagnosed through cystogenetic tests, whereas 3% of the results have shown trisomy 18 (Edwards syndrome The most frequent indications for performing genetic amniocentesis, as a result of which trisomy 18 was diagnosed, were defects in ultrasound image, including fetal hydrops which constituted 27.3% of all indications. Malformation syndrome in fetus and hydramnion constituted only 9.1% of indications for cytogenetic tests where trisomy 18 was diagnosed. The highest incidence rate of trisomy 18 was diagnosed in fetuses of women aged between 30 and 34. These were followed by 29 fetuses with Edwards syndrome in mothers aged between 25 and 29.

Is exonuclease Xrn1 a component of the P-bodies?

In eukaryotic cells, XRN1 is often found in particles known as processing bodies (P bodies) together with other proteins involved in the 5' → 3' degradation pathway, such as DCP2 and the helicase DHH1 (Me31B). In yeast and human tissue culture cells, Xrn1 has been shown to be a component of P-bodies (processing bodies), dynamic cytoplasmic granules where RNA degradation can take place. Many P-body components including LSM1, GW182, DDX3, DDX6 and XRN1, but not others like DCP1a and EDC4 are recruited to the viral replication sites, as evidenced by their colocalization at perinuclear region with viral NS3.

Decapping is a central step in eukaryotic mRNA turnover. Recent studies have identified several factors involved in catalysis and regulation of decapping. These include the following: an mRNA decapping complex containing the proteins Dcp1 and Dcp2; a nucleolar decapping enzyme, X29, involved in the degradation of U8 snoRNA and perhaps of other capped nuclear RNAs; and a decapping 'scavenger' enzyme, DcpS, that hydrolyzes the cap structure resulting from complete 3'-to-5' degradation of mRNAs by the exosome. Several proteins that stimulate mRNA decapping by the Dcp1:Dcp2 complex co-localize with Dcp1 and Dcp2, together with Xrn1, a 5'-to-3' exonuclease, to structures in the cytoplasm called processing bodies. Recent evidence suggests that the processing bodies may constitute specialized cellular compartments of mRNA turnover, which suggests that mRNA and protein localization may be integral to mRNA decay. In eukaryotic cells degradation of bulk mRNA in the 5' to 3' direction requires the consecutive action of the decapping complex (consisting of DCP1 and DCP2) and the 5' to 3' exonuclease XRN1. These enzymes are found in discrete cytoplasmic foci known as P-bodies or GW-bodies (because of the accumulation of the GW182 antigen). Proteins acting in other post-transcriptional processes have also been localized to P-bodies. These include SMG5, SMG7, and UPF1, which function in nonsense-mediated mRNA decay (NMD), and the Argonaute proteins that are essential for RNA interference (RNAi) and the micro-RNA (miRNA) pathway. In addition, XRN1 is required for degradation of mRNAs targeted by NMD and RNAi. To investigate a possible interplay between P-bodies and these post-transcriptional processes we depleted P-body or essential pathway components from Drosophila cells and analyzed the effects of these depletions on the expression of reporter constructs, allowing us to monitor specifically NMD, RNAi, or miRNA function. We show that the RNA-binding protein GW182 and the DCP1:DCP2 decapping complex are required for miRNA-mediated gene silencing, uncovering a crucial role for P-body components in the miRNA pathway. Our analysis also revealed that inhibition of one pathway by depletion of its key effectors does not prevent the functioning of the other pathways, suggesting a lack of interdependence in Drosophila. As an important mode of suppressing gene expression, messenger RNAs containing an AU-rich element (ARE) in the 3' untranslated region are rapidly degraded in the cytoplasm. ARE-mediated mRNA decay (AMD) is initiated by deadenylation, and in vitro studies have indicated that subsequent degradation occurs in the 3'-5' direction through a complex of exonucleases termed the exosome. An alternative pathway of mRNA degradation occurs at processing bodies, cytoplasmic foci that contain decapping enzymes, the 5'-3' exonuclease Xrn1 and the Lsm1-7 heptamer. To determine which of the two pathways is important for AMD in live cells, we targeted components of both pathways using short interfering RNA in human HT1080 cells. We show that Xrn1 and Lsm1 are essential for AMD. On the other side, out of three exosome components tested, only knockdown of PmScl-75 caused a strong inhibition of AMD. Our results show that mammalian cells, similar to yeast, require the 5'-3' Xrn1 pathway to degrade ARE-mRNAs. Local control of mRNA translation modulates neuronal development, synaptic plasticity, and memory formation. A poorly understood aspect of this control is the role and composition of ribonucleoprotein (RNP) particles that mediate transport and translation of neuronal RNAs. Here, we show that staufen- and FMRP-containing RNPs in Drosophila neurons contain proteins also present in somatic "P bodies," including the RNA-degradative enzymes Dcp1p and Xrn1p/Pacman and crucial components of miRNA (argonaute), NMD (Upf1p), and general translational repression (Dhh1p/Me31B) pathways. Drosophila Me31B is shown to participate (1) with an FMRP-associated, P body protein (Scd6p/trailer hitch) in FMRP-driven, argonaute-dependent translational repression in developing eye imaginal discs; (2) in dendritic elaboration of larval sensory neurons; and (3) in bantam miRNA-mediated translational repression in wing imaginal discs. These results argue for a conserved mechanism of translational control critical to neuronal function and open up new experimental avenues for understanding the regulation of mRNA function within neurons. The exoribonuclease Xrn1 is widely recognised as a key component in the 5'-3' RNA degradation pathway. This enzyme is highly conserved between yeast and humans and is known to be involved in RNA interference and degradation of microRNAs as well as RNA turnover. In yeast and human tissue culture cells, Xrn1 has been shown to be a component of P-bodies (processing bodies), dynamic cytoplasmic granules where RNA degradation can take place. In this paper we show for the first time that Pacman, the Drosophila homologue of Xrn1, is localized in cytoplasmic particles in Drosophila testis cells. These particles are present in both the mitotically dividing spermatogonia derived from primordial stem cells and in the transcriptionally active spermatocytes. Pacman is co-localized with the decapping activator dDcp1 and the helicase Me31B (a Dhh1 homologue) in these particles, although this co-localization is not completely overlapping, suggesting that there are different compartments within these granules. Particles containing Pacman respond to stress and depletion of 5'-3' decay factors in the same way as yeast P-bodies, and therefore are likely to be sites of mRNA degradation or storage. Pacman is shown to be required for normal Drosophila spermatogenesis, suggesting that control of mRNA stability is crucial in the testis differentiation pathway. Intracellular mRNA transport and local translation play a key role in neuronal physiology. Translationally repressed mRNAs are transported as a part of ribonucleoprotein (RNP) particles to distant dendritic sites, but the properties of different RNP particles and mechanisms of their repression and transport remain largely unknown. Here, we describe a new class of RNP-particles, the dendritic P-body-like structures (dlPbodies), which are present in the soma and dendrites of mammalian neurons and have both similarities and differences to P-bodies of non-neuronal cells. These structures stain positively for a number of P-body and microRNP components, a microRNA-repressed mRNA and some translational repressors. They appear more heterogeneous than P-bodies of HeLa cells, and they rarely contain the exonuclease Xrn1 but are positive for rRNA. These particles show motorized movements along dendrites and relocalize to distant sites in response to synaptic activation. Furthermore, Dcp1a is stably associated with dlP-bodies in unstimulated cells, but exchanges rapidly on neuronal activation, concomitantly with the loss of Ago2 from dlP-bodies. Thus, dlP-bodies may regulate local translation by storing repressed mRNPs in unstimulated cells, and releasing them on synaptic activation. Importin-beta family members, which shuttle between the nucleus and the cytoplasm, are essential for nucleocytoplasmic transport of macromolecules. We attempted to explore whether importin-beta family proteins change their cellular localization in response to environmental change. In this report, we show that transportin (TRN) was minimally detected in cytoplasmic processing bodies (P-bodies) under normal cell conditions but largely translocated to stress granules (SGs) in stressed cells. Fluorescence recovery after photobleaching analysis indicated that TRN moves rapidly in and out of cytoplasmic granules. Depletion of TRN greatly enhanced P-body formation but did not affect the number or size of SGs, suggesting that TRN or its cargo(es) participates in cellular function of P-bodies. Accordingly, TRN associated with tristetraprolin (TTP) and its AU-rich element (ARE)-containing mRNA substrates. Depletion of TRN increased the number of P-bodies and stabilized ARE-containing mRNAs, as observed with knockdown of the 5'-3' exonuclease Xrn1. Moreover, depletion of TRN retained TTP in P-bodies and meanwhile reduced the fraction of mobile TTP to SGs. Therefore, our data together suggest that TRN plays a role in trafficking of TTP between the cytoplasmic granules and whereby modulates the stability of ARE-containing mRNAs. Derepression of transposable elements (TEs) in the course of epigenetic reprogramming of the mouse embryonic germline necessitates the existence of a robust defense that is comprised of PIWI/piRNA pathway and de novo DNA methylation machinery. To gain further insight into biogenesis and function of piRNAs, we studied the intracellular localization of piRNA pathway components and used the combination of genetic, molecular, and cell biological approaches to examine the performance of the piRNA pathway in germ cells of mice lacking Maelstrom (MAEL), an evolutionarily conserved protein implicated in transposon silencing in fruit flies and mice. Here we show that principal components of the fetal piRNA pathway, MILI and MIWI2 proteins, localize to two distinct types of germinal cytoplasmic granules and exhibit differential association with components of the mRNA degradation/translational repression machinery. The first type of granules, pi-bodies, contains the MILI-TDRD1 module of the piRNA pathway and is likely equivalent to the enigmatic "cementing material" first described in electron micrographs of rat gonocytes over 35 years ago. The second type of granules, piP-bodies, harbors the MIWI2-TDRD9-MAEL module of the piRNA pathway and signature components of P-bodies, GW182, DCP1a, DDX6/p54, and XRN1 proteins. piP-bodies are found predomitly in the proximity of pi-bodies and the two frequently share mouse VASA homolog (MVH) protein, an RNA helicase. In Mael-mutant gonocytes, MIWI2, TDRD9, and MVH are lost from piP-bodies, whereas no effects on pi-body composition are observed. Further analysis revealed that MAEL appears to specifically facilitate MIWI2-dependent aspects of the piRNA pathway including biogenesis of secondary piRNAs, de novo DNA methylation, and efficient downregulation of TEs. Cumulatively, our data reveal elaborate cytoplasmic compartmentalization of the fetal piRNA pathway that relies on MAEL function. P-bodies (processing bodies) are cytoplasmic foci visible by light microscopy in somatic cells of vertebrate and invertebrate origin as well as in yeast, plants and trypanosomes. At the molecular level, P-bodies are dynamic aggregates of specific mRNAs and proteins that serve a dual function: first, they harbour mRNAs that are translationally silenced, and such mRNA can exit again from P-bodies to re-engage in translation. Secondly, P-bodies recruit mRNAs that are targeted for deadenylation and degradation by the decapping/Xrn1 pathway. Whereas certain proteins are core constituents of P-bodies, others involved in recognizing short-lived mRNAs can only be trapped in P-bodies when mRNA decay is attenuated. This reflects the very transient interactions by which many proteins associate with P-bodies. In the present review, we summarize recent findings on the function, assembly and motility of P-bodies. An updated list of proteins and RNAs that localize to P-bodies will help in keeping track of this fast-growing field. Candida albicans is an opportunistic fungal pathogen that grows as budding yeast, pseudohyphal, and hyphal forms. In response to external signals, C. albicans switches rapidly among these forms. mRNA-containing cytoplasmic granules, termed processing bodies (P-bodies), have been reported to accumulate under various environmental stress conditions in diverse species from yeast to mammals. Here, we provide the first microscopic and genetic characterization of P-bodies in C. albicans. The core components of P-bodies, including the decapping machinery (Dcp2 and Dhh1), 5'-3' exoribonuclease (Kem1/Xrn1), and the P-body scaffolding protein (Edc3), were identified and their localizations with respect to P-bodies were demonstrated. Various growth conditions, including glucose deprivation, hyperosmotic stress, and heat stress, stimulated the accumulation of P-bodies. In addition, we observed P-body aggregation during hyphal development. The deletion mutant strain edc3/edc3 had a defect in filamentation and exhibited a dramatic reduction in the number of P-bodies. These results suggest that Edc3 plays an essential role in the assembly and maintece of P-bodies in C. albicans, and that the switch to filamentous growth appears to accompany P-body accumulation. The p53 tumor suppressor protein is an important regulator of cell proliferation and apoptosis. p53 can be found in the nucleus and in the cytosol, and the subcellular location is key to control p53 function. In this work, we found that a widely used monoclonal antibody against p53, termed Pab 1801 (Pan antibody 1801) yields a remarkable punctate signal in the cytoplasm of several cell lines of human origin. Surprisingly, these puncta were also observed in two independent p53-null cell lines. Moreover, the foci stained with the Pab 1801 were present in rat cells, although Pab 1801 recognizes an epitope that is not conserved in rodent p53. In contrast, the Pab 1801 nuclear staining corresponded to genuine p53, as it was upregulated by p53-stimulating drugs and absent in p53-null cells. We identified the Pab 1801 cytoplasmic puncta as P Bodies (PBs), which are involved in mRNA regulation. We found that, in several cell lines, including U2OS, WI38, SK-N-SH and HCT116, the Pab 1801 puncta strictly colocalize with PBs identified with specific antibodies against the PB components Hedls, Dcp1a, Xrn1 or Rck/p54. PBs are highly dynamic and accordingly, the Pab 1801 puncta vanished when PBs dissolved upon treatment with cycloheximide, a drug that causes polysome stabilization and PB disruption. In addition, the knockdown of specific PB components that affect PB integrity simultaneously caused PB dissolution and the disappearance of the Pab 1801 puncta. Our results reveal a strong cross-reactivity of the Pab 1801 with unknown PB component(s). This was observed upon distinct immunostaining protocols, thus meaning a major limitation on the use of this antibody for p53 imaging in the cytoplasm of most cell types of human or rodent origin. In mammalian cells, proteins involved in mRNA silencing and degradation localize to discrete cytoplasmic foci called processing or P-bodies. Here we show that microscopically visible P-bodies are greatly diminished following West Nile viral infection, but the component proteins are not depleted. On the other hand, many P-body components including LSM1, GW182, DDX3, DDX6 and XRN1, but not others like DCP1a and EDC4 are recruited to the viral replication sites, as evidenced by their colocalization at perinuclear region with viral NS3. Kinetic studies suggest that the component proteins are first released from P-bodies in response to WNV infection within 12 h post-infection, followed by recruitment to the viral replication sites by 24-36 h post-infection. Silencing of the recruited proteins individually with siRNA interfered with viral replication to varying extents suggesting that the recruited proteins are required for efficient viral replication. Thus, the P-body proteins might provide novel drug targets for inhibiting viral infection. Turnover of mRNA in the cytoplasm of human cells is thought to be redundantly conducted by the monomeric 5'-3' exoribonuclease hXRN1 and the 3'-5' exoribonucleolytic RNA exosome complex. However, in addition to the exosome-associated 3'-5' exonucleases hDIS3 and hDIS3L, the human genome encodes another RNase II/R domain protein-hDIS3L2. Here, we show that hDIS3L2 is an exosome-independent cytoplasmic mRNA 3'-5' exonuclease, which exhibits processive activity on structured RNA substrates in vitro. hDIS3L2 associates with hXRN1 in an RNA-dependent manner and can, like hXRN1, be found on polysomes. The impact of hDIS3L2 on cytoplasmic RNA metabolism is revealed by an increase in levels of cytoplasmic RNA processing bodies (P-bodies) upon hDIS3L2 depletion, which also increases half-lives of investigated mRNAs. Consistently, RNA sequencing (RNA-seq) analyses demonstrate that depletion of hDIS3L2, like downregulation of hXRN1 and hDIS3L, causes changed levels of multiple mRNAs. We suggest that hDIS3L2 is a key exosome-independent effector of cytoplasmic mRNA metabolism. P bodies are 100-300 nm sized organelles involved in mRNA silencing and degradation. A total of 60 human proteins have been reported to localize to P bodies. Several human SNPs contribute to complex diseases by altering the structure and function of the proteins. Also, SNPs alter various transcription factors binding, splicing and miRNA regulatory sites. Owing to the essential functions of P bodies in mRNA regulation, we explored computationally the functional significance of SNPs in 7 P body components such as XRN1, DCP2, EDC3, CPEB1, GEMIN5, STAU1 and TRIM71. Computational analyses of non-synonymous SNPs of these components was initiated using well utilized publicly available software programs such as the SIFT, followed by PolyPhen, PANTHER, MutPred, I-Mutant-2.0 and PhosSNP 1.0. Functional significance of noncoding SNPs in the regulatory regions were analysed using FastSNP. Utilizing miRSNP database, we explored the role of SNPs in the context that alters the miRNA binding sites in the above mentioned genes. Our in silico studies have identified various deleterious SNPs and this cataloguing is essential and gives first hand information for further analysis by in vitro and in vivo methods for a better understanding of maintece, assembly and functional aspects of P bodies in both health and disease.

What is the substrate of the microbial enzyme inulinase?

The inulinase acts on the beta-(2,1)-D-fructoside links in inulin releasing D-fructose.

Strains belonging to the yeast species Kluyveromyces marxianus have been isolated from a great variety of habitats, which results in a high metabolic diversity and a substantial degree of intraspecific polymorphism. As a consequence, several different biotechnological applications have been investigated with this yeast: production of enzymes (beta-galactosidase, beta-glucosidase, inulinase, and polygalacturonases, among others), of single-cell protein, of aroma compounds, and of ethanol (including high-temperature and simultaneous saccharification-fermentation processes); reduction of lactose content in food products; production of bioingredients from cheese-whey; bioremediation; as an anticholesterolemic agent; and as a host for heterologous protein production. Compared to its congener and model organism, Kluyveromyces lactis, the accumulated knowledge on K. marxianus is much smaller and spread over a number of different strains. Although there is no publicly available genome sequence for this species, 20% of the CBS 712 strain genome was randomly sequenced (Llorente et al. in FEBS Lett 487:71-75, 2000). In spite of these facts, K. marxianus can envisage a great biotechnological future because of some of its qualities, such as a broad substrate spectrum, thermotolerance, high growth rates, and less tendency to ferment when exposed to sugar excess, when compared to K. lactis. To increase our knowledge on the biology of this species and to enable the potential applications to be converted into industrial practice, a more systematic approach, including the careful choice of (a) reference strain(s) by the scientific community, would certainly be of great value. A new thermophilic inulinase-producing strain, which grows optimally at 60 degrees C, was isolated from soil samples with medium containing inulin as a sole carbon source. It was identified as a Bacillus smithii by analysis of 16s rDNA. Maximum inulinase yield of 135.2 IU/ml was achieved with medium pH7.0, containing inulin 2.0%, (NH(4))H(2)PO(4) 0.5%, yeast extract 0.5%, at 50 degrees C 200 rpm shaker for 72-h incubation. The purified inulinase from the extracellular extract of B. smithii T7 shows endoinulinolytic activity. The optimum pH for this endoinulinase is 4.5 and stable at pH range of 4.0-8.0. The optimum temperature for enzyme activity was 70 degrees C, the half life of the endoinulinase is 9 h and 2.5 h at 70 degrees C and 80 degrees C respectively. Comparatively lower Michaelis-Menten constant (4.17 mM) and higher maximum reaction velocity (833 IU/mg protein) demonstrate the endoinulinase's greater affinity for inulin substrate. These findings are significant for its potential industrial application. Approximately 1 million tons of Agave tequilana plants are processed annually by the Mexican Tequila industry generating vast amounts of agricultural waste. The aim of this study was to investigate the potential use of Agave tequilana waste as substrate for the production of commercially important enzymes. Two strains of Aspergillus niger (CH-A-2010 and CH-A-2016), isolated from agave fields, were found to grow and propagate in submerged cultures using Agave tequilana waste as substrate. Isolates showed simultaneous extracellular inulinase, xylanase, pectinase, and cellulase activities. Aspergillus CH-A-2010 showed the highest production of inulinase activity (1.48 U/ml), whereas Aspergillus niger CH-A-2016 produced the highest xylanase (1.52 U/ml) and endo-pectinase (2.7U/ml) activities. In both cases production of enzyme activities was significantly higher on Agave tequilana waste than that observed on lemon peel and specific polymeric carbohydrates. Enzymatic hydrolysis of raw A. tequilana stems and leaves, by enzymes secreted by the isolates yielded maximum concentrations of reducing sugars of 28.2 g/l, and 9.9 g/l respectively. In conclusion, Agave tequilana waste can be utilized as substrate for the production of important biotechnological enzymes. Exoinulinase (beta-d-fructan fructohydrolase, EC 3.2.1.80) secreted by Aspergillus terreus CCT4083 was obtained using sugar cane bagasse, an agroindustrial residue, as a carbon source. It was further purified from the supernatant culture in a rapid procedure. The enzyme presented 57 kDa on SDS-PAGE and 56 kDa on gel filtration chromatography. Inulin was hydrolyzed by the purified enzyme, yielding d-fructose as the main product. This enzyme showed maximum activity at pH 4.0 and 60 degrees C and maintained more than 90 and 75% of its original activity at 40 and 50 degrees C, respectively, after 3.5 h of preincubation. The K(M) values for inulin, sucrose, and raffinose were 11, 4.20, and 27.89 mM, respectively, and d-fructose was a competitive inhibitor (K(i) = 47.55 mM). The activation energies for sucrose, raffinose, and inulin were 10.4, 5.61, and 4.44 kcal/mol, respectively. The characteristics of A. terreus exoinulinase were compared to those of inulinases isolated from other organisms. The exoinulinase traits presented especially good thermostability and the ability to produce pure d-fructose, suggesting its application to the production of high-fructose syrup. An inulinase-producing Microbulbifer sp. strain, JAM-3301, was isolated from a deep-sea sediment. An inulin operon that contained three open reading frames was cloned and sequenced. Two of the three genes were expressed. One product was an endo-inulinase, and the other was a β-fructofuranosidase. Both enzymes worked together to effectively degrade inulin. A novel extracellular exoinulinase was purified and characterized from a new yeast strain KRF1(T), and the gene encoding the enzyme was successfully cloned. The enzyme was stable at low pH between 3.0 and 6.5. The K (m) and V (max) values of the purified enzyme for inulin were 2.3 mg/mL and 4.8 mg/min, respectively. The optimum temperature of the inulinase was 50 °C, and the enzyme remained 78 % of activity at 60 °C for 2 h. The inulinase showed an amino acid sequence identity of 58 % to its closest homolog in Meyerozyma (Pichia) guilliermondii. In the secondary structure, the domain G (VMEVH) of the enzyme contained three unique residues (V, M, and H). Compared with previously reported inulinases, the enzyme from strain KRF1(T) displayed strong acid resistance, notable thermostability, and high affinity for the substrate of inulin. Based on sequence analysis of the 26S rDNA D1/D2 domain and phenotypic characterization, the yeast strain KRF1(T) was found to represent a novel anamorphic, ascomycetous yeast species. A complete description of the species is given and the name Candida kutaonensis sp. nov (type strain = KRF1(T) = AS 2.4027(T) = CBS 11388(T)) is proposed. Fructans were extracted from Agave salmiana juice, characterized and subjected to hydrolysis process using a commercial inulinase preparation acting freely. To compare the performance of the enzymatic preparation, a batch of experiments were also conducted with chicory inulin (reference). Hydrolysis was performed for 6 h at two temperatures (50, 60 °C) and two substrate concentrations (40, 60 mg/ml). Hydrolysis process was monitored by measuring the sugars released and residual substrate by HPLC. A mathematical model which describes the kinetics of substrate degradation as well as fructose production was proposed to analyze the hydrolysis assessment. It was found that kinetics were significantly influenced by temperature, substrate concentration, and type of substrate (P < 0.01). The extent of substrate hydrolysis varied from 82 to 99%. Hydrolysis product was mainly constituted of fructose, obtaining from 77 to 96.4% of total reducing sugars. This work is focused on the synthesis of the fructooligosaccharides (FOS) from sucrose and inulin, using free, immobilized and pre-treated immobilized inulinase from Kluyveromyces marxianus NRRL Y 7571 and Aspergillus niger in an aqueous-organic system. Initially, the influence of pre-treatment using four different gases, propane, n-butane, CO(2) and liquefied petroleum gas (LPG), was investigated towards FOS production and best results were found when both enzymes were previously treated with LPG. The best reaction yields were obtained when the immobilized enzymes were treated with LPG. Considering FOS synthesis using the enzyme from A. niger, yields of 26.62% of GF2 (kestose), 30.62% of GF3 (nystose) and 8.47% of GF4 (fructosyl nystose) were achieved using sucrose as substrate. Using inulinases from K. marxianus NRRL Y 7571, 11.89% of GF2 and 20.83% of GF3 were obtained, using inulin as substrate. However, promising results were achieved using the free form of inulinase from A. niger (77.19% of GF2; 14.03% of GF3 and 0.07% of GF4) using inulin as substrate. Commercial inulinase from Aspergillus niger was immobilized in montmorillonite and then treated in pressurized propane and liquefied petroleum gas (LPG). Firstly, the effects of system pressure, exposure time, and depressurization rate, using propane and LPG, on enzymatic activity were evaluated through central composite design 2³. Residual activities of 145.1 and 148.5% were observed for LPG (30 bar, 6 h, and depressurization rate of 20 bar min⁻¹) and propane (270 bar, 1 h, and depressurization rate of 100 bar min⁻¹), respectively. The catalysts treated at these conditions in both fluids were then used for the production of fructooligosaccharides (FOS) using sucrose and inulin as substrates in aqueous and organic systems. The main objective of this step was to evaluate the yield and productivity in FOS, using alternatives for enhancing enzyme activity by means of pressurized fluids and also using low-cost supports for enzyme immobilization, aiming at obtaining a stable biocatalyst to be used for synthesis reactions. Yields of 18% were achieved using sucrose as substrate in aqueous medium, showing the potential of this procedure, hence suggesting a further optimization step to increase the process yield. Inulin is a carbohydrate composed of linear chains of β-2,1-linked D-fructofuranose molecules terminated by a glucose residue through a sucrose-type linkage at the reducing end. Jerusalem artichoke (JA) is one of the most interesting materials among unconventional and renewable raw materials, with levels of inulin reaching 50-80% of dry matter. Inulin or inulin-rich materials can be actively hydrolyzed by microbial inulinases to produce glucose and fructose syrups that can be used in bioprocesses. In this study, several microbial strains were isolated and their ability to inulinase biosynthesis was evaluated. The novel yeast strain Talf1, identified as Zygosaccharomyces bailii, was the best inulinase producer, attaining 8.67 U/ml of inulinase activity when JA juice was used as the inducer substrate. Z. bailii strain Talf1 and/or its enzymatic crude extract were further applied for bioethanol production and biodesulfurization (BDS) processes, using inulin and JA juice as carbon source. In a consolidated bioprocessing for ethanol production from 200 g/l inulin, Z. bailii strain Talf1 was able to produce 67 g/l of ethanol. This ethanol yield was improved in a simultaneous saccharification and fermentation (SSF) process, with the ethanologenic yeast Saccharomyces cerevisiae CCMI 885 and the Talf1 inulinases, achieving a production of 78 g/l ethanol. However, the highest ethanol yield (∼48%) was obtained in a SSF process from JA juice (∼130 g/l fermentable sugars), where the S. cerevisiae produced 63 g/l ethanol. Relatively to the dibenzothiophene BDS tests, the Gordonia alkanivorans strain 1B achieved a desulfurization rate of 4.8 μM/h within a SSF process using Talf1 inulinases and JA juice, highlighting the potential of JA as a less expensive alternative carbon source. These results showed the high potential of Z. bailii strain Talf1 inulinases as a versatile tool for bioprocesses using inulin-rich materials. Inulin is emerging as an extremely rare source of sugar, it is having more sweetening capacity than table sugar, has beneficial effect in diabetic patient. Inulinases mainly produced by the microorganism and it degrades inulin into fructose which is a digestible form. There are more than 58 strains of microorganisms which are involved in the production of inulinases. The present report investigates about the selectivity of inulin by inulinase and its action to produce fructose through molecular docking. We have investigated exo-inulinase and endo-inulinases from Penicillium sp. TN-88(BAC16218) and Penicillium sp. TN-88(BAA19132), respectively with different arrangement of amino acids in the active site which detect the substrate. The protein sequences described above were processed to homology modeling by Swiss model and further they were docked with 1-ketose and fructose-6-phosphate as substrate by DOCK6 software package (dock.compbio.ucsf.edu). The results of the present studies represented that fructose-6-phosphate ((2R,3R,4S) fructose-6-phosphate) was having better interaction with exo-inulinase showing grid score of -40.288094 and the conserved amino acid Asp-22, Asp 128, Asp 179 and Ser 84 of exo-inulinase are involved in the bonding. In addition to this it was also seen that 1-ketose ((3S,4R)-ketose 1-phosphate) did not shown any interaction with the conserved part of the endo-inulinase. Thirty fungal species grown on Cichorium intybus L. root extract as a sole carbon source, were screened for the production of exo-inulinase activities. The thermophile Thielavia terrestris NRRL 8126 and mesophile Aspergillus foetidus NRRL 337 gave the highest production levels of inulinases I & II at 50 and 24 ºC respectively. Yeast extract and peptone were the best nitrogen sources for highest production of inulinases I & II at five and seven days of incubation respectively. The two inulinases I & II were purified to homogeneity by gel-filtration and ion-exchange chromatography with 66.0 and 42.0 fold of purification respectively. The optimum temperatures of purified inulinases I & II were 75 and 50 ºC respectively. Inulinase I was more thermostable than the other one. The optimum pH for activity was found to be 4.5 and 5.5 for inulinases I & II respectively. A comparatively lower Michaelis-Menten constant (2.15 mg/ml) and higher maximum initial velocity (115 µmol/min/mg of protein) for inulinase I on inulin demonstrated the exoinulinase's greater affinity for inulin substrate. These findings are significant for its potential industrial application. The molecular mass of the inulinases I & II were estimated to be 72 & 78 kDa respectively by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Various carbon sources were evaluated for production of inulinase by yeast, Kluyveromyces marxianus MTCC 3995. Highest inulinase activity was observed with Dahlia extract (25.3 nkat mL(-1)) as carbon source. The enzyme activity was 1.4 folds higher than that observed in media containing pure chicory inulin (17.8 nkat mL(-1)). The yeast showed good growth on a simple medium containing dahlia extract (20% w/v) and yeast extract (2%w/v) as carbon and nitrogen source respectively, in 96 h. at 28°C and 120 rpm. Lowest inulinase yield (4.8 nkat mL(-1)) was seen in the medium containing glucose as C-source. Although varied inulinase levels were noticed on different C- sources, Inulinase: Sucrase (I/S) ratios were noticed to be similar. Among various protein sources tested, yeast extract was found to be the best source followed by beef extract (17.9 nkat mL(-1)) and peptone (13.8 nkat mL(-1)). The enzyme was optimally active at pH (4.0) and 50°C. TLC analysis of end product revealed that inulinase hydrolyzed inulin exclusively into fructose. Results suggest that the dahlia extract induced exoinulinase synthesis in Kluyveromyces marxianus and can be utilized as a potential substrate for inulinase production.

What is the treatment of acute myocarditis?

Treatment of acute myocarditis includes antiinflammatory drugs like ibuoprofen and steroids, inotropic agents and mechanical support (intra-aortic ballon pump). TandemHeart percutaneous ventricular assist device may be used in some, more compromised, patients for few days.

OBJECTIVE: To clarify the effects of Astragalus Membranaceus (AM) combined with taurine and/or coenzyme Q10(CoQ10) on coxsackievirus B3 (CVB3) murine myocarditis. METHODS: Viral myocarditis model was created by intraperitoneal inoculation with CVB3 solution and were treated by saline, AM, taurine, CoQ10, AM + taurine, AM + CoQ10, AM + taurine + CoQ10, respectively. The mortality, ECG, CVB3-RNA in myocardium and myocardial histopathologic changes were observed. RESULTS: AM combined with taurine and CoQ10 could significantly reduce the mortality of the mice and the incidence of abnormal ECG at acute stage. CVB3-RNA was significantly reduced in AM treated group, especially in AM + taurine group. No anti-virus effect was found in CoQ10 group. All drugs could lighten myocardial histopathologic changes and the effect could be enhanced by combined treatment. CONCLUSIONS: AM, taurine and CoQ10 have some curative effects on CVB3 murine myocarditis, AM combined with taurine and CoQ10 is the best. We report a successful case of extracorporeal membrane oxygenation (ECMO) support for a 7-year-old girl with acute fulmit myocarditis, and describe the pitfalls and management of ECMO. The problem with ECMO is that it may not reduce the afterload of the left ventricle (LV), and may be associated with increased LV wall stress and deteriorating pulmonary congestion. It is important for ECMO management to find the best balance between flow support and LV afterload. Acute fulmit myocarditis commonly manifests itself as severe, rapidly progressive hemodynamic deterioration and circulatory collapse that may be resistant to high doses of inotropic agents and steroids and to mechanical support by intra-aortic balloon pump. Acute myocarditis has a high mortality rate and may necessitate heart transplantation. The best short-term therapy available to support the patient may be a percutaneous left ventricular assist device. One such unit, the TandemHeart percutaneous ventricular assist device, can enable patients to recover in a few days. Two of our patients who experienced profound, therapy-resistant heart failure arising from acute myocarditis were successfully supported by the TandemHeart. To the best of our knowledge, these are the 1st reported cases in which the TandemHeart percutaneous ventricular assist device served as a bridge to recovery from acute fulmit myocarditis. La Société canadienne de cardiologie avait publié un ensemble complet de recommandations sur le diagnostic et la prise en charge de l’insuffisance cardiaque en janvier 2006. Selon les commentaires obtenus par l’entremise d’un programme national d’ateliers sur l’insuffisance cardiaque et par une sollicitation active des principaux intéressés, plusieurs thèmes ont été jugés importants pour le praticien. Les thèmes retenus pour la présente mise à jour incluent : les pratiques optimales en matière de diagnostic et de prise en charge de l’insuffisance cardiaque droite, de la myocardite et des dispositifs thérapeutiques et une revue des récentes études cliniques importantes ou détermites. Ces recommandations ont été rédigées avec une approche structurée pour l’analyse et l’évaluation des preuves que la Société a adoptées et décrites précédemment. Cette mise à jour a été rédigée d’un point de vue clinique pour plus de convivialité et de commodité. Les questions cliniques spécifiquement abordées sont notamment : Qu’est-ce que l’insuffisance cardiaque droite et comment approche-t-on les épreuves diagnostiques? Quelles autres entités cliniques peuvent prendre l’aspect de cette maladie nébuleuse et comment les distinguer? Quand doit-on s’inquiéter de la présence de myocardite et avec quelle rapidité les patients atteints de cette maladie doivent-ils être adressés vers un centre spécialisé? Parmi la myriade d’essais cliniques détermits publiés récemment, lesquels auront un impact sur nos normes de soins cliniques? Les objectifs sont d’aider les médecins et autres professionnels de la santé à traiter de manière optimale les patients atteints d’insuffisance cardiaque, de manière à exercer un impact mesurable sur leur santé et sur le pronostic clinique de la maladie au Canada. Kawasaki's disease is a disease of unknown cause. The characteristic clinical features of Kawasaki's disease are fever> or =102 degrees F for> or =5 days accompanied by a bilateral bulbar conjunctivitis/conjunctival suffusion, erythematous rash, cervical adenopathy, pharyngeal erythema, and swelling of the dorsum of the hands/feet. Kawasaki's disease primarily affects children and is rare in adults. In children, Kawasaki's disease is more likely to be associated with aseptic meningitis, coronary artery aneurysms, and thrombocytosis. In adult Kawasaki's disease, unilateral cervical adenopathy, arthritis, conjunctival suffusion/conjunctivitis, and elevated serum transaminases (serum glutamic oxaloacetic transaminase [SGOT]/serum glutamate pyruvate transaminase [SGPT]) are more likely. Kawasaki's disease in adults may be mimicked by other acute infections with fever and rash, that is, group A streptococcal scarlet fever, toxic shock syndrome (TSS), and Rocky Mountain Spotted Fever (RMSF). Because there are no specific tests for Kawasaki's disease, diagnosis is based on clinical criteria and the syndromic approach. In addition to rash and fever, scarlet fever is characterized by circumoral pallor, oropharyngeal edema, Pastia's lines, and peripheral eosinophilia, but not conjunctival suffusion, splenomegaly, swelling of the dorsum of the hands/feet, thrombocytosis, or an elevated SGOT/SGPT. In TSS, in addition to rash and fever, there is conjunctival suffusion, oropharyngeal erythema, and edema of the dorsum of the hands/feet, an elevated SGOT/SGPT, and thrombocytopenia. Patients with TSS do not have cervical adenopathy or splenomegaly. RMSF presents with fever and a maculopapular rash that becomes petechial, first appearing on the wrists/ankles after 3 to 5 days. RMSF is accompanied by a prominent headache, periorbital edema, conjunctival suffusion, splenomegaly, thrombocytopenia, an elevated SGOT/SGPT, swelling of the dorsum of the hands/feet, but not oropharyngeal erythema. We present a case of adult Kawasaki's disease with myocarditis and splenomegaly. The patient's myocarditis rapidly resolved, and he did not develop coronary artery aneurysms. In addition to splenomegaly, this case of adult Kawasaki's disease is remarkable because the patient had highly elevated serum ferritin levels of 944-1303 ng/mL; (normal<189 ng/mL). To the best of our knowledge, this is the first report of adult Kawasaki's disease with highly elevated serum ferritin levels. This is also the first report of splenomegaly in adult Kawasaki's disease. We conclude that Kawasaki's disease should be considered in the differential diagnosis in adult patients with rash/fever for> or =5 days with conjunctival suffusion, cervical adenopathy, swelling of the dorsum of the hands/feet, thrombocytosis and otherwise unexplained highly elevated ferritin levels.

List causative genes for autosomal recessive forms of monogenic Parkinson's disease

Causative genes for autosomal recessive forms of monogenic Parkinson's disease are: PARK2 PARK7 PINK1 PARK9 PARK14 PARK15

Mutations of the parkin gene on chromosome 6 cause autosomal recessive, early onset parkinsonism. This is the most frequent form of monogenic parkinsonism so far identified. The associated phenotypical spectrum encompasses early onset, levodopa-responsive parkinsonism (average onset in the early 30s in Europe), and it overlaps with dopa-responsive dystonia in cases with the earliest onset, and with clinically typical Parkinson's disease in cases with later onset. Despite clinical features, Lewy bodies are not found at autopsy in brains of patients with parkin mutations. The parkin protein possesses ubiquitin ligase activity, which is abolished by the pathogenic mutations. Rare monogenic forms of Parkinson's disease (PD) are promoting our understanding of the molecular pathways involved in the common, non-Mendelian forms of the disease. Here, we focus on PARK7, an autosomal recessive form of early-onset parkinsonism caused by mutations in the DJ-1 gene. We first review the genetics of this form and the rapidly expanding knowledge about the structure and biochemical properties of the DJ-1 protein. We also discuss how DJ-1 dysfunction might lead to neurodegeneration, and the implications of this novel piece of information for the pathogenesis of the common PD forms. Although much work remains to be done to clarify the biology of DJ-1, its proposed activity as a molecular chaperone and/or as oxidative sensor appear intriguing in the light of the current theories on the pathogenesis of PD. The identification of rare monogenic forms of Parkinson's disease (PD) has provided tremendous insight into the molecular pathogenesis of this disorder. Heritable mutations in alpha-synuclein, parkin, DJ-1 and PINK1 cause familial forms of PD. In the more common sporadic form of PD, oxidative stress and derangements in mitochondrial complex-I function are considered to play a prominent role in disease pathogenesis. However, the relationship of DJ-1 with other PD-linked genes and oxidative stress has not been explored. Here, we show that pathogenic mutant forms of DJ-1 specifically but differentially associate with parkin, an E3 ubiquitin ligase. Chemical cross-linking shows that pathogenic DJ-1 mutants exhibit impairments in homo-dimer formation, suggesting that parkin may bind to monomeric DJ-1. Parkin fails to specifically ubiquitinate and enhance the degradation of L166P and M26I mutant DJ-1, but instead promotes their stability in cultured cells. The interaction of parkin with L166P DJ-1 may involve a larger protein complex that contains CHIP and Hsp70, perhaps accounting for the lack of parkin-mediated ubiquitination. Oxidative stress also promotes an interaction between DJ-1 and parkin, but this does not result in the ubiquitination or degradation of DJ-1. Parkin-mediated alterations in DJ-1 protein stability may be pathogenically relevant as DJ-1 levels are dramatically increased in the detergent-insoluble fraction from sporadic PD/DLB brains, but are reduced in the insoluble fraction from parkin-linked autosomal recessive juvenile-onset PD brains. These data potentially link DJ-1 and parkin in a common molecular pathway at multiple levels that may have important implications for understanding the pathogenesis of inherited and sporadic PD. The identification of monogenic variants of Parkinson's disease (PD) has provided novel insights into its unknown pathogenesis. As the first protein linked to autosomal-recessive forms of PD, Parkin became a welcome tool to explain biochemical and neuropathological observations that had suggested involvement of the ubiquitin-proteasome system (UPS) in PD. Based on cellular expression studies and biochemical in vitro experiments, several researchers ascribed an E3-type, E2-dependent ubiquitin protein ligase activity to wild-type (but not mutant) Parkin proteins. Although the individual components of the proposed Parkin ubiquitin ligase complex in the normal human brain remain to be identified and the E3 ligase effect of Parkin function has not yet been confirmed in an animal model, the scientific exploration of a protein with several links to the UPS has provided many leads in PD research. This chapter describes assays that the authors have used to examine the cellular and in vitro effects of neural Parkin. PURPOSE OF REVIEW: Parkinson's disease is the second most common neurodegenerative disorder and affects 2% of the population over the age of 60 years. Due to the increasing proportion of elderly individuals in developed countries, Parkinson's disease and related neurodegenerative disorders represent a growing burden on the health care system. In the majority of cases, the cause of the disease is still unknown, and its elucidation remains one of the major challenges of the neurosciences. Recent findings in rare genetic forms of Parkinson's disease have allowed the development of novel animal models, providing a basis for a better understanding of the molecular pathogenesis of the disease, setting the stage for the development of novel treatment strategies. RECENT FINDINGS: Several novel genes for monogenic forms of Parkinson's disease, such as PINK-1 for an autosomal-recessive early-onset variant, and LRRK2 for a relatively common late-onset autosomal-domit form have recently been discovered, and several novel animal models have been generated on the basis of genes that had been found earlier. SUMMARY: The combination of genetic, pathologic and molecular findings provide increasing evidence that the pathways identified through the cloning of different disease genes are interacting on different levels and share several major pathogenic mechanisms. Parkinson's disease (PD) is a slowly progressive neurodegenerative disorder characterized clinically by bradykinesia, rigidity, tremor, gait dysfunction, and postural instability. Several genes have been identified for monogenic disorders that variably resemble Parkinson's disease. Here, we focus on PARK7, a gene relates to an autosomal recessive form of early-onset Parkinsonism and encodes a protein named DJ-1. Though the exact role of DJ-1 needs to be elucidated, it is generally thought to be functioned as a molecular chaperone and an oxidative sensor (or antioxidative factor). We will review the protective role of DJ-1 to prevent dopaminergic neurons in the substantia nigra pars compacta (SNpc) from degeneration and how its dysfunction would lead to neurodegeneration. PTEN-induced putative kinase 1 (PINK1) is a causative gene for autosomal recessive early onset parkinsonism. Mutations in PINK1 were identified originally in PARK6-linked parkinsonism families from Italy and Spain. PINK1 contains 8 exons spanning 1.8 kb, and encodes a protein of 581 amino acids with a mitochondrial targeting motif and a serine-threonine protein kinase domain. Until now PINK1-mutation positive parkinsonism is the second frequent one next to parkin among autosomal recessive parkinsonism. Most of reported mutations were distributed throughout the serine-threonine protein kinase domain. Thus, loss of function of kinase activity of PINK1 is the most probable disease mechanism. The clinical phenotype of PINK1 -mutation positive parkinsonism is similar to that of parkin mutation positive parkinsonism. Single heterozygous mutations of PINK1 have been also identified sporadic Parkinson's disease (PD) patients. The presence of dopamine hypometabolism in asymptomatic mutation carriers suggests that single heterozygous mutations of PINK1 are risk factors for developing parkinsonism. In addition, some functional data have been shown that PINK1 protein may function as neuroprotective roles for mitochondria. Recent biochemical and morphological studies using drosophila melanogaster suggested that Parkin and PINK1 share a common pathway to maintain mitochondrial function and that PINK1 functions upstream of Parkin. Moreover, co-expression of double mutations of PINK1 and DJ-1 in cultured cells from one family with heterozygous mutations, enhanced susceptibility to MPP+ (1-methyl-4-phenylpyridinium ion)-induced cell death. These data suggest that PINK1, parkin, and/or DJ-1 could play an important role to maintain mitochondrial functions. In the other word, the mitochondrion is a good target for elucidating the pathogenesis of not only sporadic form but also monogenic form of PD. Parkinson's disease (PD) is an etiologically heterogeneous disorder characterized by parkinsonism (bradykinesia, resting tremor, rigidity, and postural instability) with good response to L-dopa. PD is the second most prevalent neurodegenerative disorder after Alzheimer disease. Although the majority of PD cases are sporadic, 5-10% of PD is monogenic form of PD as familial PD (FPD). Multifactorial genetic-environmental interaction has been thought in PD pathogenesis, although these interactions are still poorly understood. In 2004, LRRK2 was identified as the causative gene for PARK8 originally mapped in the large Japanese Sagamihara family with late-onset autosomal domit PD (ADPD). Patients with LRRK2 mutations account for approximately 2-13% of ADPD and 0.5-3% of sporadic PD. Genetically, LRRK2 mutations have been distributed worldwide with some ethnic differences by single founder effect such as G2019S, R1441G, and G2385R variants. LRRK2 G2385R was reported to be a risk factor for sporadic PD in Asia. Clinically, most patients with LRRK2 mutations develop typical idiopathic PD, however, variable clinical features and pathologies such as diffuse Lewy body disease, multiple system atrophy, progressive supranuclear palsy, and amyotrophic lateral sclerosis have been reported. Although Lewy bodies have been considered as a pathological hallmark for sporadic PD classically, some FPD and sporadic PD patients with heterozygous LRRK2 mutations or homozygous parkin mutations have no Lewy bodies. On the other hand, LRRK2 was reported as a component of Lewy bodies. Based on the variability, multifunction of LRRK2 such as phosphorylation of other proteins, especially, alpha-synuclein and tau, have been suggested. As interaction of Parkin and LRRK2 was reported, interaction and intersection among the autosomal-recessive or autosomal-domit PD proteins could be involved in some common pathways, and LRRK2 may play an important role as a key FPD gene product. Identification of PARK8 and LRRK2 has given meaningful insights in not only PD but also numerous neurodegenerative disorders such as synucleinopathies and tauopathies with or without Lewy bodies. Over the last few years, several genes for monogenic forms of Parkinson's disease (PD) have been mapped and/or cloned. Mutations have been identified in the gene for alpha-synuclein in rare families with domit PD, indicating that aggregation of this protein in Lewy bodies is probably a crucial step in the molecular pathogenesis of the disorder. A much more common cause for domit PD, mutations in the gene for leucine-rich repeat kinase 2 (LRRK2), has recently been identified. Mutations in the parkin gene, in DJ-1 and PINK1 all cause autosomal recessive parkinsonism of early onset. These genes have been implicated in the proteasomal protein degradation pathway, in the oxidative stress response and mitochondrial function. Mutations in recessive genes probably are pathogenic through loss-of-function mechanisms, suggesting that their wildtype products protect dopaminergic cells against a variety of insults. Evidence is emerging that at least some of these genes may play a direct role in the etiology of the common sporadic form of PD. Further, it is likely that the cellular pathways identified in rare monogenic variants of the disease also shed light on the molecular pathogenesis in typical sporadic PD. Parkinson's disease (PD) is a common neurodegenerative disorder in the aging population, affecting more than 1% over the age of 65 years. Certain rare forms of the disease are monogenic, representing 5-10% of PD patients, but there is increasing evidence that multiple genetic risk factors are important also for common forms of PD. To date, 13 genetic loci, PARK1-13, have been suggested for rare forms of PD such as autosomal domit and autosomal recessive PD. At six of these loci, genes have been identified and reported by several groups to carry mutations that are linked to affected family members. Genes in which mutations have been linked to familial PD have also been shown to be candidate genes for idiopathic forms of PD, as those same genes may also carry other mutations that merely increase the risk. Four of the PARK genes, SNCA at PARK1, UCH-L1 at PARK5, PINK1 at PARK6 and LRRK2 at PARK8, have been implicated in sporadic PD. There are indeed multiple genetic risk factors that combine in different ways to increase or decrease risk, and several of these need to be identified in order to begin unwinding the causative pathways leading to the different forms of PD. In this review, we present the molecular genetics of PD that are understood today, to help explain the pathways leading to neurodegeneration. Genetic findings have changed our views on Parkinson's disease (PD) and parkinsonism, which will be collectively referred to as Parkinsonian Syndrome (PS) in the present manuscript. Mutations in several genes are found to cause monogenic forms of the disorder. Point mutations, duplications and triplications in the alpha-synuclein gene cause a rare domit form of PS in families. Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene have been identified as a much more common cause for domit PS, especially in certain ethnic groups, while mutations in the parkin gene, in DJ-1, PINK1 and ATP13A2 cause autosomal recessive parkinsonism of early onset. The monogenic variants are important tools in identifying cellular pathways that also shed light on the molecular pathogenesis of sporadic PS and some of these genes may play a role in the etiology of the common sporadic form of PS. Here we add recent findings to a greatly challenging puzzle. Over the last few years, genetic findings have changed our views on Parkinson's disease (PD), as mutations in a growing number of genes are found to cause monogenic forms of the disorder. Point mutations in the gene for alpha-synuclein, as well as duplications and triplications of the wild-type gene cause a domit form of PD in rare families, pointing towards mishandling of this protein as a crucial step in the molecular pathogenesis of the disorder. Mutations in the gene for leucine-rich repeat kinase 2 (LRRK2) have recently been identified as a much more common cause for domit PD, while mutations in the parkin gene, in DJ-1, PINK1 and ATP13A2 all cause autosomal-recessive parkinsonism of early onset. Mutations in recessive genes probably are pathogenic through loss-of-function mechanisms, suggesting that their wild-type products protect dopaminergic cells against a variety of insults. Evidence is emerging that at least some of these genes may play a direct role in the etiology of the common sporadic form of PD. Further, it is likely that the cellular pathways identified in rare monogenic variants of the disease also shed light on the molecular pathogenesis in typical sporadic PD. Research in Parkinson's disease (PD) genetics has been extremely prolific over the past decade. More than 13 loci and 9 genes have been identified, but their implication in PD is not always certain. Point mutations, duplications and triplications in the alpha-synuclein (SNCA) gene cause a rare domit form of PD in familial and sporadic cases. Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are a more frequent cause of autosomal domit PD, particularly in certain ethnic groups. Loss-of-function mutations in Parkin, PINK1, DJ-1 and ATP13A2 cause autosomal recessive parkinsonism with early-onset. Identification of other Mendelian forms of PD will be a main challenge for the next decade. In addition, susceptibility variants that contribute to PD have been identified in several populations, such as polymorphisms in the SNCA, LRRK2 genes and heterozygous mutations in the beta-glucocerebrosidase (GBA) gene. Genome-wide associations and re-sequencing projects, together with gene-environment interaction studies, are expected to further define the causal role of genetic determits in the pathogenesis of PD, and improve prevention and treatment. Recently, several genes for parkinsonism have been identified. Among them, familial Parkinson's disease (PD) could be assigned for PARK disorders. PARK disorders consist of three different inherited modes such as autosomal recessive, autosomal domit modes and susceptible genes. Some of them manifest not only typical parkinsonism, but also dystonia, pyramidal sign, and mental dysfunctions. While the monogenic forms of PARK disorders have been reviewed extensively, it is not easy to do differential diagnosis of PARK disorders due to the additional features except for typical parkinsonism. In this presentation, we focus on two different scenarios of patients with autosomal domit parkinsonism: (1) parkinsonism with mutations in one of the PARK genes; (2) parkinsonism with mutations other than PARK genes or yet other genes where parkinsonism is a well recognized, concomitant, or even an isolated feature. Several forms of autosomal recessive parkinsonism are known. In three forms, caused by mutations in parkin (PARK2), PINK1 (PARK6), or DJ-1 (PARK7), the phenotype is usually characterized by levodopa-responsive parkinsonism without atypical features. Parkin mutations are most frequent, explaining -50% of the cases with a clinical diagnosis of familial Parkinson's disease compatible with recessive inheritance and onset <45 years, and -15% of the sporadic cases with onset <45. Mutations in PINK1 and DJ-1 are less common, accounting for -1-8%, and -1-2% of the sporadic cases with early-onset. Since point mutations and genomic rearrangements can be present, sequencing and exon dosage are both required for accurate mutational screening of these genes. The phenotype of parkin mutations is characterized by early-onset parkinsonism, good response to levodopa, and benign course. The average onset age is in the 30s, but late-onset cases have been described. The phenotype associated with PINK1 and DJ-1 mutations has been studied in a smaller number of patients but it is overall indistinguishable from that of parkin. Mutations in other genes, including ATP13A2 (PARK9), PLA2G6 (PARK14), and FBX07 (PARK15), cause more rare forms of recessive parkinsonism with very early-onset (<30 years) and usually additional, atypical features (pyramidal, dystonic, ocular movement, and cognitive disturbances). Yet, it is expected that other monogenic forms of parkinsonism will be identified in the future, as mutations in the above-mentioned genes are not found in other patients with similar phenotypes. Parkinson's disease (PD) occurs in both familial and sporadic forms, and both monogenic and complex genetic factors have been identified. Early onset PD (EOPD) is particularly associated with autosomal recessive (AR) mutations, and three genes, PARK2, PARK7 and PINK1, have been found to carry mutations leading to AR disease. Since mutations in these genes account for less than 10% of EOPD patients, we hypothesized that further recessive genetic factors are involved in this disorder, which may appear in extended runs of homozygosity.We carried out genome wide SNP genotyping to look for extended runs of homozygosity (ROHs) in 1,445 EOPD cases and 6,987 controls. Logistic regression analyses showed an increased level of genomic homozygosity in EOPD cases compared to controls. These differences are larger for ROH of 9 Mb and above, where there is a more than three-fold increase in the proportion of cases carrying a ROH. These differences are not explained by occult recessive mutations at existing loci. Controlling for genome wide homozygosity in logistic regression analyses increased the differences between cases and controls, indicating that in EOPD cases ROHs do not simply relate to genome wide measures of inbreeding. Homozygosity at a locus on chromosome19p13.3 was identified as being more common in EOPD cases as compared to controls. Sequencing analysis of genes and predicted transcripts within this locus failed to identify a novel mutation causing EOPD in our cohort.There is an increased rate of genome wide homozygosity in EOPD, as measured by an increase in ROHs. These ROHs are a signature of inbreeding and do not necessarily harbour disease-causing genetic variants. Although there might be other regions of interest apart from chromosome 19p13.3, we lack the power to detect them with this analysis. Homozygous or compound heterozygous mutations in the phosphatase and tensin homolog-induced putative kinase 1 (PINK1) gene are causative of autosomal recessive, early onset Parkinson's disease. Single heterozygous mutations have been detected repeatedly both in a subset of patients and in unaffected individuals, and the significance of these mutations has long been debated. Several neurophysiological studies from non-manifesting PINK1 heterozygotes have demonstrated the existence of neural plasticity abnormalities, indicating the presence of specific endophenotypic traits in the heterozygous state. We performed a functional analysis of corticostriatal synaptic plasticity in heterozygous PINK1 knockout (PINK1(+/-) ) mice using a multidisciplinary approach and observed that, despite normal motor behavior, repetitive activation of cortical inputs to striatal neurons failed to induce long-term potentiation (LTP), whereas long-term depression was normal. Although nigral dopaminergic neurons exhibited normal morphological and electrophysiological properties with normal responses to dopamine receptor activation, a significantly lower dopamine release was measured in the striatum of PINK1(+/-) mice compared with control mice, suggesting that a decrease in stimulus-evoked dopamine overflow acts as a major determit for the LTP deficit. Accordingly, pharmacological agents capable of increasing the availability of dopamine in the synaptic cleft restored normal LTP in heterozygous mice. Moreover, monoamine oxidase B inhibitors rescued physiological LTP and normal dopamine release. Our results provide novel evidence for striatal plasticity abnormalities, even in the heterozygous disease state. These alterations might be considered an endophenotype to this monogenic form of Parkinson's disease and a valid tool with which to characterize early disease stage and design possible disease-modifying therapies.

How does ranolazine affect calcium handling in the heart

Ranolazine has only a small effect on the basal calcium current, while it greatly affects whole cell calcium current when facilitated by beta-adrenoceptor or histamine receptor activation. Ranolazine is a novel agent that inhibits the late sodium current thereby reducing cellular sodium and calcium overload. Ranolazine reduces Ca2+ overload and LV mechanical dysfunction during ischemia/reperfusion. ranolazine decreases I(Na,L)-induced dysregulation of calcium cycling that contributes to the antiarrhythmic actions of this agent. ranolazine desensitizes Ca(2+)-dependent RyR2 activation, and inhibits Ca(i) oscillations. ranolazine ameliorates the Ca(2+) response and cross-bridge kinetics of cardiac myofilaments.

1. Ranolazine has protective effects against ischaemia as exemplified by a reduction of the associated enzyme release and an attenuation of the fall of ATP and other metabolic changes. It has been suggested that ranolazine may affect GTP-binding proteins involved in the beta-adrenergic protein kinase A (PKA) cascade by interacting with Gs. Calcium channel currents are stimulated by this cascade but the effect of ranolazine upon them is not known. The whole cell patch clamp technique was used to examine the action of ranolazine on basal calcium channel currents and those stimulated by activation at various steps in the PKA cascade. 2. Ranolazine had only a small effect on the basal calcium current (100 microM caused 11.3% inhibition), but markedly attenuated the beta-adrenoceptor stimulated current (20 nM isoprenaline increased current by 2.3 fold, 10 microM ranolazine inhibited this increase by 47.6%). When the PKA cascade was activated downstream to the receptor by either G-protein activation with Gpp[NH]p or adenylate cyclase activation with forskolin, the calcium current showed a sensitivity to ranolazine similar to the basal current. Activation of the PKA cascade via H2 receptors gave rise to currents which showed an intermediate sensitivity to ranolazine. Ranolazine inhibition of ICa persisted during muscarinic attenuation of beta-adrenoceptor activation. 3. The results indicate that ranolazine, at concentrations which have significantly beneficial effects during ischaemic episodes, only greatly affects whole cell calcium current when facilitated by beta-adrenoceptor or histamine receptor activation. Ranolazine would appear to act at the receptor level, rather than at the GTP-binding or Gs/adenylate cyclase level. An additional smaller effect is also present, which may be mediated by a direct effect on the channel, or components closely associated with it. BACKGROUND: Despite advances in antithrombotic therapies and invasive technology, the risk of recurrent ischemic complications in patients with non-ST-elevation acute coronary syndromes (NSTE-ACSs) remains substantial. Ranolazine is a novel agent that inhibits the late sodium current thereby reducing cellular sodium and calcium overload and has been shown to reduce ischemia in patients with chronic stable angina. STUDY DESIGN: MERLIN-TIMI 36 is a phase III, randomized, double-blind, parallel-group, placebo-controlled, multinational clinical trial to evaluate the efficacy and safety of ranolazine during long-term treatment of patients with NSTE-ACS receiving standard therapy (N = 6500). Eligible patients are randomized 1:1 to ranolazine or matched placebo, initiated as 200 mg intravenously over 1 hour, followed by an 80-mg/h infusion (40 mg/h for patients with severe renal insufficiency) for up to 96 hours and oral ranolazine ER 1000 mg BID or matched placebo until the end of study. The primary end point is the time to first occurrence of any element of the composite of cardiovascular death, myocardial infarction, or recurrent ischemia. Secondary end points include ischemia on Holter monitoring, hospitalization for new or worsening heart failure, quality of life measures, and exercise performance. The evaluation of long-term safety will include death from any cause and symptomatic documented arrhythmia. Recruitment began in October 2004. The trial will continue until 730 major cardiovascular events and 310 deaths are recorded with expected completion in 24 to 28 months. CONCLUSIONS: MERLIN-TIMI 36 will evaluate the role of ranolazine in the acute and chronic management of patients presenting with NSTE-ACS. Ranolazine is a selective inhibitor of the late sodium current relative to peak sodium channel current, and via this mechanism, it may decrease sodium-dependent intracellular calcium overload during ischemia and reperfusion. Ranolazine reduces the frequency of angina attacks, but there is little information on its effects on myocardial stunning after short-term ischemia. The objective of this study was to test the effects of ranolazine on left ventricular (LV) function and myocardial stunning after ischemia/reperfusion in rabbits. Myocardial stunning was induced in rabbits by 15 minutes of coronary artery occlusion (CAO) followed by 3 hours reperfusion. Ten minutes before CAO, rabbits were randomly assigned to vehicle (n = 15) or ranolazine (2 mg/kg bolus plus 60 microg/kg/min infusion, IV, n = 15). Myocardial stunning was assessed by LV 2-dimensional echocardiography using, as a marker of severity, ischemic free-wall fractional thickening (FWft; systolic wall thickness - diastolic wall thickness/diastolic wall thickness). Regional ejection fraction (EF) was also assessed. During CAO, FWft was depressed in both groups, indicating an ischemic insult (FWft was reduced from 0.62 +/- 0.05 at baseline to 0.10 +/- 0.04 in vehicle and from 0.73 +/- 0.05 to 0.26 +/- 0.07 in ranolazine, P < 0.05, ranolazine vs vehicle). After reperfusion, previously ischemic myocardium remained stunned; however, FWft recovered significantly better in ranolazine (0.51 +/- 0.05) than in vehicle (0.35 +/- 0.04, P = .027). Baseline EF was 0.65 +/- 0.02 in the ranolazine and 0.68 +/- 0.02 in vehicle (P = ns). During CAO, EF was reduced by 36% +/- 6% in vehicle versus only 20% +/- 6% in ranolazine (P < .05). At the end of reperfusion, EF remained depressed in both groups, but the reduction in the vehicle group (25% +/- 5%) was significantly worse than in ranolazine (9% +/- 4%, P = .017). Improvement in function was independent of necrosis (negligible) or differences in hemodynamics (no differences between groups). Ranolazine treatment reduced myocardial stunning following brief ischemia/reperfusion suggesting that inhibiting the late sodium channel current may be a novel approach to treating stunning independent of effects on hemodynamics. The goal of this study was to test the hypothesis that the novel anti-ischemic drug ranolazine, which is known to inhibit late I(Na), could reduce intracellular [Na(+)](i) and diastolic [Ca(2+)](i) overload and improve diastolic function. Contractile dysfunction in human heart failure (HF) is associated with increased [Na(+)](i) and elevated diastolic [Ca(2+)](i). Increased Na(+) influx through voltage-gated Na(+) channels (late I(Na)) has been suggested to contribute to elevated [Na(+)](i) in HF. In isometrically contracting ventricular muscle strips from end-stage failing human hearts, ranolazine (10 micromol/L) did not exert negative inotropic effects on twitch force amplitude. However, ranolazine significantly reduced frequency-dependent increase in diastolic tension (i.e., diastolic dysfunction) by approximately 30% without significantly affecting sarcoplasmic reticulum (SR) Ca(2+) loading. To investigate the mechanism of action of this beneficial effect of ranolazine on diastolic tension, Anemonia sulcata toxin II (ATX-II, 40 nmol/L) was used to increase intracellular Na(+) loading in ventricular rabbit myocytes. ATX-II caused a significant rise in [Na(+)](i) typically seen in heart failure via increased late I(Na). In parallel, ATX-II significantly increased diastolic [Ca(2+)](i). In the presence of ranolazine the increases in late I(Na), as well as [Na(+)](i) and diastolic [Ca(2+)](i) were significantly blunted at all stimulation rates without significantly decreasing Ca(2+) transient amplitudes or SR Ca(2+) content. In summary, ranolazine reduced the frequency-dependent increase in diastolic tension without having negative inotropic effects on contractility of muscles from end-stage failing human hearts. Moreover, in rabbit myocytes the increases in late I(Na), [Na(+)](i) and [Ca(2+)](i) caused by ATX-II, were significantly blunted by ranolazine. These results suggest that ranolazine may be of therapeutic benefit in conditions of diastolic dysfunction due to elevated [Na(+)](i) and diastolic [Ca(2+)](i). Pathological conditions, including ischemia and heart failure, are associated with altered sodium channel function and increased late sodium current (I(Na,L)), leading to prolonged action potential duration, increased intracellular sodium and calcium concentrations, and arrhythmias. We used anemone toxin (ATX)-II to study the effects of increasing I(Na,L) on intracellular calcium cycling in rat isolated hearts. Cardiac contraction was abolished using paralytic agents. Ranolazine (RAN) was used to inhibit late I(Na). Hearts were loaded with fluo-4-acetoxymethyl ester, and myocyte intracellular calcium transients (CaTs) were measured using laser scanning confocal microscopy. ATX (1 nM) prolonged CaT duration at 50% recovery in hearts paced at a basal rate of 2 Hz and increased the sensitivity of the heart to the development of calcium alters caused by fast pacing. ATX increased the time required for recovery of CaT amplitude following a previous beat, and ATX induced spontaneous calcium release waves during rapid pacing of the heart. ATX prolonged the duration of repolarization from the initiation of the activation to terminal repolarization in the pseudo-electrocardiogram. All actions of ATX were both reversed and prevented by subsequent or prior exposure, respectively, of hearts to RAN (10 microM). Most importantly, the increased vulnerability of the heart to the development of calcium alters during rapid pacing was reversed or prevented by 10 microM RAN. These results suggest that enhancement of I(Na,L) alters calcium cycling. Reduction by RAN of I(Na,L)-induced dysregulation of calcium cycling could contribute to the antiarrhythmic actions of this agent in both reentrant and triggered arrhythmias. PURPOSE: Ranolazine is a novel antianginal medication that acts by ameliorating disturbed sodium and calcium homeostasis. By preventing myocyte sodium and calcium overload, ranolazine also have potential beneficial effects on myocardial function. Experimental models support this concept, as do 2 small studies in human participants receiving ranolazine intravenously. We evaluated changes in parameters of left ventricular function in stable angina patients treated with oral ranolazine. METHODS: Twenty-two participants were enrolled with Doppler echocardiography performed at baseline and a mean of 2 months after initiation of treatment. RESULTS: Global left ventricular function, as assessed by the myocardial performance index, was significantly improved on drug therapy (P < .0001). This was due to improvement in both diastolic and systolic parameters. Of 21 patients, 17 reported less angina and 8 patients reported an increase in activity level. CONCLUSIONS: We report improved parameters of left ventricular function in response to ranolazine as used in the clinical setting. RATIONALE: Previously, we demonstrated that a deoxycorticosterone acetate (DOCA)-salt hypertensive mouse model produces cardiac oxidative stress and diastolic dysfunction with preserved systolic function. Oxidative stress has been shown to increase late inward sodium current (I(Na)), reducing the net cytosolic Ca(2+) efflux. OBJECTIVE: Oxidative stress in the DOCA-salt model may increase late I(Na), resulting in diastolic dysfunction amenable to treatment with ranolazine. METHODS AND RESULTS: Echocardiography detected evidence of diastolic dysfunction in hypertensive mice that improved after treatment with ranolazine (E/E':sham, 31.9 ± 2.8, sham+ranolazine, 30.2 ± 1.9, DOCA-salt, 41.8 ± 2.6, and DOCA-salt+ranolazine, 31.9 ± 2.6; P=0.018). The end-diastolic pressure-volume relationship slope was elevated in DOCA-salt mice, improving to sham levels with treatment (sham, 0.16 ± 0.01 versus sham+ranolazine, 0.18 ± 0.01 versus DOCA-salt, 0.23 ± 0.2 versus DOCA-salt+ranolazine, 0.17 ± 0.0 1 mm Hg/L; P<0.005). DOCA-salt myocytes demonstrated impaired relaxation, τ, improving with ranolazine (DOCA-salt, 0.18 ± 0.02, DOCA-salt+ranolazine, 0.13 ± 0.01, sham, 0.11 ± 0.01, sham+ranolazine, 0.09 ± 0.02 seconds; P=0.0004). Neither late I(Na) nor the Ca(2+) transients were different from sham myocytes. Detergent extracted fiber bundles from DOCA-salt hearts demonstrated increased myofilament response to Ca(2+) with glutathionylation of myosin binding protein C. Treatment with ranolazine ameliorated the Ca(2+) response and cross-bridge kinetics. CONCLUSIONS: Diastolic dysfunction could be reversed by ranolazine, probably resulting from a direct effect on myofilaments, indicating that cardiac oxidative stress may mediate diastolic dysfunction through altering the contractile apparatus. BACKGROUND: Ranolazine is a new antianginal drug that reduces intracellular sodium and calcium accumulation during ischemia, thus potentially limiting myocardial ischemia. It remains unknown, however, if the drug can play a role in the pathophysiology of periprocedural myocardial infarction. The aim of this study was to verify in a randomized study if pretreatment with ranolazine before percutaneous coronary intervention (PCI) has any protective effect on periprocedural myocardial damage. METHODS: Seventy patients with stable angina (age 62 ± 18 years, 42 men) scheduled for elective coronary intervention entered a randomized, double-blind, placebo-controlled pilot trial. For 7 days before the procedure, 35 patients were assigned to receive ranolazine (1,000 mg twice daily) and 35 patients had placebo. Creatine kinase-MB and troponin I levels were measured at baseline and at 8 and 24 hours postprocedure. RESULTS: Comparison between the 2 groups did not show any difference in clinical features, extent of coronary artery disease, and technical aspects of PCI. Periprocedural myocardial infarction (ie, postprocedural increase of creatine kinase-MB ≥ 3 times above the upper limit of normal) was less commonly seen after PCI in the ranolazine than in the placebo group (6% vs 22%, P = .041). Detection of markers of myocardial injury above the upper limit of normal was less common [corrected] in the ranolazine vs placebo group: 23% vs 40% for creatine kinase-MB (P = .010) and 31% vs 48% for troponin I (P = .011). [corrected] Postprocedural peak markers levels were also significantly lower in the ranolazine vs placebo group (creatine kinase-MB: 3.1 ± 15.0 and 7.7 ± 19.1 ng/mL, P < .05; troponin I: 0.15 ± 0.35 and 0.47 ± 0.49 ng/mL, P < .05). No significant adverse effect was reported by the 2 groups of patients. CONCLUSIONS: Pretreatment with ranolazine 1,000 mg twice daily for 7 days significantly reduced procedural myocardial injury in elective PCI. Excessive reverse-mode (RM) sodium/calcium exchanger 1.1 (NCX1.1) activity, resulting from intracellular sodium accumulation caused by reduced Na+/K+-ATPase activity, increased Na-H exchanger 1 activity. The induction of the voltage-gated sodium channel late current component (late INa), is a major pathway for intracellular calcium (Ca2+i) loading in cardiac ischemia-reperfusion (IR) injury and cardiac glycoside toxicity. Inhibition of late INa with the antianginal agent ranolazine is protective in models of IR injury and cardiac glycoside toxicity. However, whether inhibition of late INa alone is sufficient to provide maximal protection or additional inhibition of RM NCX1.1 provides further benefit remains to be determined conclusively. Therefore, the effects of ranolazine were compared with the INa inhibitor lidocaine in models of IR injury and ouabain toxicity, RM NCX1.1-mediated Ca2+ overload, and patch-clamp assays of RM NCX1.1 currents. Ranolazine and lidocaine (10 μM) similarly reduced Ca2+i overload and improved left ventricle work recovery in whole-heart models of IR injury or exposure to ouabain (80 μM). Ranolazine (10 μM), but not lidocaine (10 μM), reduced RM NCX1.1-mediated Ca2+i overload in ventricular myocytes. Furthermore, ranolazine inhibited RM NCX1.1 currents (IC50 1.7 μM), without affecting forward mode currents, revealing that ranolazine has novel RM NCX1.1 inhibitory actions. However, because lidocaine provides similar protection to ranolazine in whole-heart models but does not inhibit RM NCX1.1, we conclude that induction of late INa is upstream of RM NCX1.1 activity and selective inhibition of late INa alone is sufficient to reduce Ca2+i overload and contractile dysfunction in IR injury and cardiac glycoside toxicity. The effective treatment of coronary artery disease targets two distinct goals, controlling symptomatic angina and decreasing the adverse events associated with ischemia. Traditional anti-anginal and anti-ischemic drugs function by altering the determits of myocardial oxygen supply or demand, usually by altering loading conditions, changing the heart rate, or impacting contractility. Blockade of the late inward sodium current, late I(Na), offers another target for the treatment of ischemia. Blockade of late I(Na) reduces the sodium and calcium overload that follows ischemia. This improves myocardial relaxation and reduces left ventricular diastolic stiffness, in turn enhancing myocardial contractility and perfusion. Ranolazine, a late I(Na) inhibitor, has been shown to provide both anti-anginal and anti-ischemic benefits without significant alterations in the heart rate and blood pressure in patients with stable coronary artery disease. When evaluated in patients with acute coronary syndrome, ranolazine has been shown to decrease recurrent ischemia, but not significantly reduce the risk of death or myocardial infarction. This review will address the rationale that inhibition of the late sodium current is beneficial in reducing cardiac dysfunction during ischemia, and discuss the clinical studies supporting the use of ranolazine for its anti-anginal and anti-ischemic effects. BACKGROUND: Hypertrophic cardiomyopathy (HCM), the most common mendelian heart disorder, remains an orphan of disease-specific pharmacological treatment because of the limited understanding of cellular mechanisms underlying arrhythmogenicity and diastolic dysfunction. METHODS AND RESULTS: We assessed the electromechanical profile of cardiomyocytes from 26 HCM patients undergoing myectomy compared with those from nonfailing nonhypertrophic surgical patients by performing patch-clamp and intracellular Ca(2+) (Ca(2+)(i)) studies. Compared with controls, HCM cardiomyocytes showed prolonged action potential related to increased late Na(+) (I(NaL)) and Ca(2+) (I(CaL)) currents and decreased repolarizing K(+) currents, increased occurrence of cellular arrhythmias, prolonged Ca(2+)(i) transients, and higher diastolic Ca(2+)(i). Such changes were related to enhanced Ca(2+)/calmodulin kinase II (CaMKII) activity and increased phosphorylation of its targets. Ranolazine at therapeutic concentrations partially reversed the HCM-related cellular abnormalities via I(NaL) inhibition, with negligible effects in controls. By shortening the action potential duration in HCM cardiomyocytes, ranolazine reduced the occurrence of early and delayed afterdepolarizations. Finally, as a result of the faster kinetics of Ca(2+)(i) transients and the lower diastolic Ca(2+)(i), ranolazine accelerated the contraction-relaxation cycle of HCM trabeculae, ameliorating diastolic function. CONCLUSIONS: We highlighted a specific set of functional changes in human HCM myocardium that stem from a complex remodeling process involving alterations of CaMKII-dependent signaling, rather than being a direct consequence of the causal sarcomeric mutations. Among the several ion channel and Ca(2+)(i) handling proteins changes identified, an enhanced I(NaL) seems to be a major contributor to the electrophysiological and Ca(2+)(i) dynamic abnormalities of ventricular myocytes and trabeculae from patients with HCM, suggesting potential therapeutic implications of I(NaL) inhibition. Calpain is an intracellular Ca²⁺-activated protease that is involved in numerous Ca²⁺ dependent regulation of protein function in many cell types. This paper tests a hypothesis that calpains are involved in Ca²⁺-dependent increase of the late sodium current (INaL) in failing heart. Chronic heart failure (HF) was induced in 2 dogs by multiple coronary artery embolization. Using a conventional patch-clamp technique, the whole-cell INaL was recorded in enzymatically isolated ventricular cardiomyocytes (VCMs) in which INaL was activated by the presence of a higher (1 μM) intracellular [Ca²⁺] in the patch pipette. Cell suspensions were exposed to a cell- permeant calpain inhibitor MDL-28170 for 1-2 h before INaL recordings. The numerical excitation-contraction coupling (ECC) model was used to evaluate electrophysiological effects of calpain inhibition in silico. MDL caused acceleration of INaL decay evaluated by the two-exponential fit (τ₁ = 42±3.0 ms τ₂ = 435±27 ms, n = 6, in MDL vs. τ₁ = 52±2.1 ms τ₂ = 605±26 control no vehicle, n = 11, and vs. τ₁ = 52±2.8 ms τ₂ = 583±37 ms n = 7, control with vehicle, P<0.05 ANOVA). MDL significantly reduced INaL density recorded at -30 mV (0.488±0.03, n = 12, in control no vehicle, 0.4502±0.0210, n = 9 in vehicle vs. 0.166±0.05pA/pF, n = 5, in MDL). Our measurements of current-voltage relationships demonstrated that the INaL density was decreased by MDL in a wide range of potentials, including that for the action potential plateau. At the same time the membrane potential dependency of the steady-state activation and inactivation remained unchanged in the MDL-treated VCMs. Our ECC model predicted that calpain inhibition greatly improves myocyte function by reducing the action potential duration and intracellular diastolic Ca²⁺ accumulation in the pulse train. CONCLUSIONS: Calpain inhibition reverses INaL changes in failing dog ventricular cardiomyocytes in the presence of high intracellular Ca²⁺. Specifically it decreases INaL density and accelerates INaL kinetics resulting in improvement of myocyte electrical response and Ca²⁺ handling as predicted by our in silico simulations.

Which is the primary distinction between the Reverse Warburg effect and the conventional Warburg effect?

The conventional "Warburg effect" reffers to the metabolic shift of cancer cells towards aerobic glycolysis, due to mitochondrial dysfunction. The "reverse Warburg effect" or "parasitic" energy-transfer, is a model of "two-compartment tumor metabolism". In this model, cancer cells secrete hydrogen peroxide (H2O2), initiating oxidative stress and aerobic glycolysis in the tumor stroma. The cancer-associated fibroblasts of the stroma are glycolytic and lack detectable mitochondria. These glycolytic stromal cells produce mitochondrial fuels (L-lactate, ketone bodies and chemical building blocks, such as amino acids -glutamine-, and nucleotides) that are then transferred to oxidative epithelial cancer cells. Lactate and ketones drive cancer cell oxidative mitochondrial metabolism (OXPHOS), and building blocks sustain the anabolic needs of rapidly proliferating cancer cells. Therefore, according to the "reverse Warburg effect", stromal catabolism fuels anabolic tumor growth via energy transfer. Thus, in "reverse Warburg effect" the cancer-associated fibroblasts of the stroma undergo aerobic glycolysis, rather than epithelial cancer cells themselves, as proposed by the conventional "Warburg effect".

Here, we propose a new model for understanding the Warburg effect in tumor metabolism. Our hypothesis is that epithelial cancer cells induce the Warburg effect (aerobic glycolysis) in neighboring stromal fibroblasts. These cancer-associated fibroblasts, then undergo myo-fibroblastic differentiation, and secrete lactate and pyruvate (energy metabolites resulting from aerobic glycolysis). Epithelial cancer cells could then take up these energy-rich metabolites and use them in the mitochondrial TCA cycle, thereby promoting efficient energy production (ATP generation via oxidative phosphorylation), resulting in a higher proliferative capacity. In this alternative model of tumorigenesis, the epithelial cancer cells instruct the normal stroma to transform into a wound-healing stroma, providing the necessary energy-rich micro-environment for facilitating tumor growth and angiogenesis. In essence, the fibroblastic tumor stroma would directly feed the epithelial cancer cells, in a type of host-parasite relationship. We have termed this new idea the "Reverse Warburg Effect." In this scenario, the epithelial tumor cells "corrupt" the normal stroma, turning it into a factory for the production of energy-rich metabolites. This alternative model is still consistent with Warburg's original observation that tumors show a metabolic shift towards aerobic glycolysis. In support of this idea, unbiased proteomic analysis and transcriptional profiling of a new model of cancer-associated fibroblasts (caveolin-1 (Cav-1) deficient stromal cells), shows the upregulation of both (1) myo-fibroblast markers and (2) glycolytic enzymes, under normoxic conditions. We validated the expression of these proteins in the fibroblastic stroma of human breast cancer tissues that lack stromal Cav-1. Importantly, a loss of stromal Cav-1 in human breast cancers is associated with tumor recurrence, metastasis, and poor clinical outcome. Thus, an absence of stromal Cav-1 may be a biomarker for the "Reverse Warburg Effect," explaining its powerful predictive value. We and others have previously identified a loss of stromal caveolin-1 (Cav-1) in cancer-associated fibroblasts (CAFs) as a powerful single independent predictor of breast cancer patient tumor recurrence, metastasis, tamoxifen-resistance, and poor clinical outcome. However, it remains unknown how loss of stromal Cav-1 mediates these effects clinically. To mechanistically address this issue, we have now generated a novel human tumor xenograft model. In this two-component system, nude mice are co-injected with i) human breast cancer cells (MDA-MB-231), and ii) stromal fibroblasts (wild-type (WT) versus Cav-1 (-/-) deficient). This allowed us to directly evaluate the effects of a Cav-1 deficiency solely in the tumor stromal compartment. Here, we show that Cav-1-deficient stromal fibroblasts are sufficient to promote both tumor growth and angiogenesis, and to recruit Cav-1 (+) micro-vascular cells. Proteomic analysis of Cav-1-deficient stromal fibroblasts indicates that these cells upregulate the expression of glycolytic enzymes, a hallmark of aerobic glycolysis (the Warburg effect). Thus, Cav-1-deficient stromal fibroblasts may contribute towards tumor growth and angiogenesis, by providing energy-rich metabolites in a paracrine fashion. We have previously termed this new idea the "Reverse Warburg Effect". In direct support of this notion, treatment of this xenograft model with glycolysis inhibitors functionally blocks the positive effects of Cav-1-deficient stromal fibroblasts on breast cancer tumor growth. Thus, pharmacologically-induced metabolic restriction (via treatment with glycolysis inhibitors) may be a promising new therapeutic strategy for breast cancer patients that lack stromal Cav-1 expression. We also identify the stromal expression of PKM2 and LDH-B as new candidate biomarkers for the "Reverse Warburg Effect" or "Stromal-Epithelial Metabolic Coupling" in human breast cancers. Cancer cells do not exist as pure homogeneous populations in vivo. Instead they are embedded in "cancer cell nests" that are surrounded by stromal cells, especially cancer associated fibroblasts. Thus, it is not unreasonable to suspect that stromal fibroblasts could influence the metabolism of adjacent cancer cells, and visa versa. In accordance with this idea, we have recently proposed that the Warburg effect in cancer cells may be due to culturing cancer cells by themselves, out of their normal stromal context or tumor microenvironment. In fact, when cancer cells are co-cultured with fibroblasts, then cancer cells increase their mitochondrial mass, while fibroblasts lose their mitochondria. An in depth analysis of this phenomenon reveals that aggressive cancer cells are "parasites" that use oxidative stress as a "weapon" to extract nutrients from surrounding stromal cells. Oxidative stress in fibroblasts induces the autophagic destruction of mitochondria, by mitophagy. Then, stromal cells are forced to undergo aerobic glycolysis, and produce energy-rich nutrients (such as lactate and ketones) to "feed" cancer cells. This mechanism would allow cancer cells to seed anywhere, without blood vessels as a food source, as they could simply induce oxidative stress wherever they go, explaining how cancer cells survive during metastasis. We suggest that stromal catabolism, via autophagy and mitophagy, fuels the anabolic growth of tumor cells, promoting tumor progression and metastasis. We have previously termed this new paradigm "The Autophagic Tumor Stroma Model of Cancer Metabolism", or the "Reverse Warburg Effect". We also discuss how glutamine addiction (glutaminolysis) in cancer cells fits well with this new model, by promoting oxidative mitochondrial metabolism in aggressive cancer cells. Breast cancer progression and metastasis are driven by complex and reciprocal interactions, between epithelial cancer cells and their surrounding stromal microenvironment. We have previously shown that a loss of stromal Cav-1 expression is associated with an increased risk of early tumor recurrence, metastasis and decreased overall survival. To identify and characterize the signaling pathways that are activated in Cav-1 negative tumor stroma, we performed gene expression profiling using laser microdissected breast cancer-associated stroma. Tumor stroma was laser capture microdissected from 4 cases showing high stromal Cav-1 expression and 7 cases with loss of stromal Cav-1. Briefly, we identified 238 gene transcripts that were upregulated and 232 gene transcripts that were downregulated in the stroma of tumors showing a loss of Cav-1 expression (p ≤ 0.01 and fold-change ≥ 1.5). Gene set enrichment analysis (GSEA) revealed "stemness," inflammation, DNA damage, aging, oxidative stress, hypoxia, autophagy and mitochondrial dysfunction in the tumor stroma of patients lacking stromal Cav-1. Our findings are consistent with the recently proposed "Reverse Warburg Effect" and the "Autophagic Tumor Stroma Model of Cancer Metabolism." In these two complementary models, cancer cells induce oxidative stress in adjacent stromal cells, which then forces these stromal fibroblasts to undergo autophagy/mitophagy and aerobic glycolysis. This, in turn, produces recycled nutrients (lactate, ketones and glutamine) to feed anabolic cancer cells, which are undergoing oxidative mitochondrial metabolism. Our results are also consistent with previous biomarker studies showing that the increased expression of known autophagy markers (such as ATG16L and the cathepsins) in the tumor stroma is specifically associated with metastatic tumor progression and/or poor clinical outcome. Recently, we proposed a new mechanism for understanding the Warburg effect in cancer metabolism. In this new paradigm, cancer-associated fibroblasts undergo aerobic glycolysis, and extrude lactate to "feed" adjacent cancer cells, which then drives mitochondrial biogenesis and oxidative mitochondrial metabolism in cancer cells. Thus, there is vectorial transport of energy-rich substrates from the fibroblastic tumor stroma to anabolic cancer cells. A prediction of this hypothesis is that cancer-associated fibroblasts should express MCT4, a mono-carboxylate transporter that has been implicated in lactate efflux from glycolytic muscle fibers and astrocytes in the brain. To address this issue, we co-cultured MCF7 breast cancer cells with normal fibroblasts. Interestingly, our results directly show that breast cancer cells specifically induce the expression of MCT4 in cancer-associated fibroblasts; MCF7 cells alone and fibroblasts alone, both failed to express MCT4. We also show that the expression of MCT4 in cancer-associated fibroblasts is due to oxidative stress, and can be prevented by pre-treatment with the anti-oxidant N-acetyl-cysteine. In contrast to our results with MCT4, we see that MCT1, a transporter involved in lactate uptake, is specifically upregulated in MCF7 breast cancer cells when co-cultured with fibroblasts. Virtually identical results were also obtained with primary human breast cancer samples. In human breast cancers, MCT4 selectively labels the tumor stroma, e.g., the cancer-associated fibroblast compartment. Conversely, MCT1 was selectively expressed in the epithelial cancer cells within the same tumors. Functionally, we show that overexpression of MCT4 in fibroblasts protects both MCF7 cancer cells and fibroblasts against cell death, under co-culture conditions. Thus, we provide the first evidence for the existence of a stromal-epithelial lactate shuttle in human tumors, analogous to the lactate shuttles that are essential for the normal physiological function of muscle tissue and brain. These data are consistent with the "reverse Warburg effect," which states that cancer-associated fibroblasts undergo aerobic glycolysis, thereby producing lactate, which is utilized as a metabolic substrate by adjacent cancer cells. In this model, "energy transfer" or "metabolic-coupling" between the tumor stroma and epithelial cancer cells "fuels" tumor growth and metastasis, via oxidative mitochondrial metabolism in anabolic cancer cells. Most importantly, our current findings provide a new rationale and novel strategy for anti-cancer therapies, by employing MCT inhibitors. Previously, we proposed that cancer cells behave as metabolic parasites, as they use targeted oxidative stress as a "weapon" to extract recycled nutrients from adjacent stromal cells. Oxidative stress in cancer-associated fibroblasts triggers autophagy and  mitophagy, resulting in compartmentalized cellular catabolism, loss of mitochondrial function, and the onset of aerobic glycolysis, in the tumor stroma. As such, cancer-associated fibroblasts produce high-energy nutrients (such as lactate and ketones) that fuel mitochondrial biogenesis, and oxidative metabolism in cancer cells. We have termed this new energy-transfer mechanism the "reverse Warburg effect." To further test the validity of this hypothesis, here we used an in vitro MCF7-fibroblast co-culture system, and quantitatively measured a variety of metabolic parameters by FACS analysis (analogous to laser-capture micro-dissection).  Mitochondrial activity, glucose uptake, and ROS production were measured with highly-sensitive fluorescent probes (MitoTracker, NBD-2-deoxy-glucose, and DCF-DA). Interestingly, using this approach, we directly show that cancer cells initially secrete hydrogen peroxide that then triggers oxidative stress in neighboring fibroblasts. Thus, oxidative stress is contagious (spreads like a virus) and is propagated laterally and vectorially from cancer cells to adjacent fibroblasts. Experimentally, we show that oxidative stress in cancer-associated fibroblasts quantitatively reduces mitochondrial activity, and increases glucose uptake, as the fibroblasts become more dependent on aerobic glycolysis.  Conversely, co-cultured cancer cells show significant increases in mitochondrial activity, and corresponding reductions in both glucose uptake and GLUT1 expression. Pre-treatment of co-cultures with extracellular catalase (an anti-oxidant enzyme that detoxifies hydrogen peroxide) blocks the onset of oxidative stress, and potently induces the death of cancer cells, likely via starvation.  Given that cancer-associated fibroblasts show the largest increases in glucose uptake, we suggest that PET imaging of human tumors, with Fluoro-2-deoxy-D-glucose (F-2-DG), may be specifically detecting the tumor stroma, rather than epithelial cancer cells. We have previously demonstrated that enhanced aerobic glycolysis and/or autophagy in the tumor stroma supports epithelial cancer cell growth and aggressive behavior, via the secretion of high-energy metabolites. These nutrients include lactate and ketones, as well as chemical building blocks, such as amino acids (glutamine) and nucleotides. Lactate and ketones serve as fuel for cancer cell oxidative metabolism, and building blocks sustain the anabolic needs of rapidly proliferating cancer cells. We have termed these novel concepts the "Reverse Warburg Effect," and the "Autophagic Tumor Stroma Model of Cancer Metabolism." We have also identified a loss of stromal caveolin-1 (Cav-1) as a marker of stromal glycolysis and autophagy. The aim of the current study was to provide genetic evidence that enhanced glycolysis in stromal cells favors tumorigenesis. To this end, normal human fibroblasts were genetically-engineered to express the two isoforms of pyruvate kinase M (PKM1 and PKM2), a key enzyme in the glycolytic pathway. In a xenograft model, fibroblasts expressing PKM1 or PKM2 greatly promoted the growth of co-injected MDA-MB-231 breast cancer cells, without an increase in tumor angiogenesis. Interestingly, PKM1 and PKM2 promoted tumorigenesis by different mechanism(s). Expression of PKM1 enhanced the glycolytic power of stromal cells, with increased output of lactate. Analysis of tumor xenografts demonstrated that PKM1 fibroblasts greatly induced tumor inflammation, as judged by CD45 staining. In contrast, PKM2 did not lead to lactate accumulation, but triggered a "pseudo-starvation" response in stromal cells, with induction of an NFκB-dependent autophagic program, and increased output of the ketone body 3-hydroxy-buryrate. Strikingly, in situ evaluation of Complex IV activity in the tumor xenografts demonstrated that stromal PKM2 expression drives mitochondrial respiration specifically in tumor cells. Finally, immuno-histochemistry analysis of human breast cancer samples lacking stromal Cav-1 revealed PKM1 and PKM2 expression in the tumor stroma. Thus, our data indicate that a subset of human breast cancer patients with a loss of stromal Cav-1 show profound metabolic changes in the tumor microenvironment. As such, this subgroup of patients may benefit therapeutically from potent inhibitors targeting glycolysis, autophagy and/or mitochondrial activity (such as metformin). We have recently proposed a new model of cancer metabolism to explain the role of aerobic glycolysis and L-lactate production in fueling tumor growth and metastasis. In this model, cancer cells secrete hydrogen peroxide (H2O2), initiating oxidative stress and aerobic glycolysis in the tumor stroma. This, in turn, drives L-lactate secretion from cancer-associated fibroblasts. Secreted L-lactate then fuels oxidative mitochondrial metabolism (OXPHOS) in epithelial cancer cells, by acting as a paracrine onco-metabolite. We have previously termed this type of two-compartment tumor metabolism the "Reverse Warburg Effect," as aerobic glycolysis takes place in stromal fibroblasts, rather than epithelial cancer cells. Here, we used MCT4 immuno-staining of human breast cancer tissue microarrays (TMAs; > 180 triple-negative patients) to directly assess the prognostic value of the "Reverse Warburg Effect." MCT4 expression is a functional marker of hypoxia, oxidative stress, aerobic glycolysis, and L-lactate efflux. Remarkably, high stromal MCT4 levels (score = 2) were specifically associated with decreased overall survival (< 18% survival at 10 y post-diagnosis). In contrast, patients with absent stromal MCT4 expression (score = 0), had 10-y survival rates of ~97% (p-value < 10 (-32) ). High stromal levels of MCT4 were strictly correlated with a loss of stromal Cav-1 (p-value < 10 (-14) ), a known marker of early tumor recurrence and metastasis. In fact, the combined use of stromal Cav-1 and stromal MCT4 allowed us to more precisely identify high-risk triple-negative breast cancer patients, consistent with the goal of individualized risk-assessment and personalized cancer treatment. However, epithelial MCT4 staining had no prognostic value, indicating that the "conventional" Warburg effect does not predict clinical outcome. Thus, the "Reverse Warburg Effect" or "parasitic" energy-transfer is a key determit of poor overall patient survival. As MCT4 is a druggable-target, MCT4 inhibitors should be developed for the treatment of aggressive breast cancers, and possibly other types of human cancers. Similarly, we discuss how stromal MCT4 could be used as a biomarker for identifying high-risk cancer patients that could likely benefit from treatment with FDA-approved drugs or existing MCT-inhibitors (such as, AR-C155858, AR-C117977, and AZD-3965). Cigarette smoke has been directly implicated in the disease pathogenesis of a plethora of different human cancer subtypes, including breast cancers. The prevailing view is that cigarette smoke acts as a mutagen and DNA damaging agent in normal epithelial cells, driving tumor initiation. However, its potential negative metabolic effects on the normal stromal microenvironment have been largely ignored. Here, we propose a new mechanism by which carcinogen-rich cigarette smoke may promote cancer growth, by metabolically "fertilizing" the host microenvironment. More specifically, we show that cigarette smoke exposure is indeed sufficient to drive the onset of the cancer-associated fibroblast phenotype via the induction of DNA damage, autophagy and mitophagy in the tumor stroma. In turn, cigarette smoke exposure induces premature aging and mitochondrial dysfunction in stromal fibroblasts, leading to the secretion of high-energy mitochondrial fuels, such as L-lactate and ketone bodies. Hence, cigarette smoke induces catabolism in the local microenvironment, directly fueling oxidative mitochondrial metabolism (OXPHOS) in neighboring epithelial cancer cells, actively promoting anabolic tumor growth. Remarkably, these autophagic-senescent fibroblasts increased breast cancer tumor growth in vivo by up to 4-fold. Importantly, we show that cigarette smoke-induced metabolic reprogramming of the fibroblastic stroma occurs independently of tumor neo-angiogenesis. We discuss the possible implications of our current findings for the prevention of aging-associated human diseases and, especially, common epithelial cancers, as we show that cigarette smoke can systemically accelerate aging in the host microenvironment. Finally, our current findings are consistent with the idea that cigarette smoke induces the "reverse Warburg effect," thereby fueling "two-compartment tumor metabolism" and oxidative mitochondrial metabolism in epithelial cancer cells. Autophagy is a highly regulated-cell pathway for degrading long-lived proteins as well as for clearing cytoplasmic organelles. Autophagy is a key contributor to cellular homeostasis and metabolism. Warburg hypothesized that cancer growth is frequently associated with a deviation of a set of energy generation mechanisms to a nonoxidative breakdown of glucose. This cellular phenomenon seems to rely on a respiratory impairment, linked to mitochondrial dysfunction. This mitochondrial dysfunction results in a switch to anaerobic glycolysis. It has been recently suggested that epithelial cancer cells may induce the Warburg effect in neighboring stromal fibroblasts in which autophagy was activated. These series of observations drove to the proposal of a putative reverse Warburg effect of pathophysiological relevance for, at least, some tumor phenotypes. In this review we introduce the autophagy process and its regulation and its selective pathways and role in cancer cell metabolism. We define and describe the Warburg effect and the newly suggested "reverse" hypothesis. We also discuss the potential value of modulating autophagy with several pharmacological agents able to modify the Warburg effect. The association of the Warburg effect in cancer and stromal cells to tumor-related autophagy may be of relevance for further development of experimental therapeutics as well as for cancer prevention.

What is the role of per genes in circadian rhythm control?

PER1 and PER2 genes are involved in cell cycle regulation and tumor suppression, controlling expression of genes such as c-Myc, Cyclin D1, Cyclin A, Mdm-2 and Gadd45alpha.

Period (Per) genes are key circadian rhythm regulators in mammals. Expression of mouse Per (mPer) genes has a diurnal pattern in the suprachiasmatic nucleus and in peripheral tissues. Genetic ablation mPER1 and mPER2 function results in a complete loss of circadian rhythm control based on wheel-running activity in mice. In addition, these animals also display apparent premature aging and a significant increase in neoplastic and hyperplastic phenotypes. When challenged by gamma radiation, mPer2-deficient mice respond by rapid hair graying, are deficient in p53-mediated apoptosis in thymocytes, and have robust tumor occurrences. Studies have demonstrated that the circadian clock function is very important for cell cycle, DNA damage response, and tumor suppression in vivo. The temporal expression of genes involved in cell cycle regulation and tumor suppression, such as c-Myc, Cyclin D1, Cyclin A, Mdm-2, and Gadd45alpha, is deregulated in mPer2 mutant mice. Genetic studies have demonstrated that many key regulators of cell cycle and growth control are also important circadian clock regulators, confirming the critical role of circadian function in organismal homeostasis. The Period (Per) genes are key circadian rhythm regulators in mammals. Expression of the mouse Per (mPer) genes have diurnal pattern in the suprachiamstic nuclei and in peripheral tissues. Genetic ablation mPER1 and mPER2 function results in a complete loss of circadian rhythm control based on wheel running activity in mice. In addition, these animals also display apparent premature aging and significant increase in neoplastic and hyperplastic phenotypes. When challenged by gamma-radiation, mPer2 deficient mice response by rapid hair graying, are deficient in p53-mediated apoptosis in thymocytes and have robust tumor occurrences. Our studies have demonstrated that the circadian clock function is very important for cell cycle, DNA damage response and tumor suppression in vivo. Temporal expression of genes involved in cell cycle regulation and tumor suppression, such as c-Myc, Cyclin D1, Cyclin A, Mdm-2 and Gadd45alpha is deregulated in mPer2 mutant mice. In addition, genetic studies have demonstrated that many key regulators of cell cycle and growth control are also important circadian clock regulators confirming the critical role of circadian function in organismal homeostasis. Recently studies of human breast and endometrial cancers revealed that the loss and deregulation of PERIOD proteins is common in the tumor cells.

Can sorafenib activate AMPK?

Sorafenib induces persisten AMPK activation

The multikinase inhibitor sorafenib is under clinical investigation for the treatment of many solid tumors, but in most cases, the molecular target responsible for the clinical effect is unknown. Furthermore, enhancing the effectiveness of sorafenib using combination strategies is a major clinical challenge. Here, we identify sorafenib as an activator of AMP-activated protein kinase (AMPK), in a manner that involves either upstream LKB1 or CAMKK2. We further show in a phase II clinical trial in KRAS mutant advanced non-small cell lung cancer (NSCLC) with single agent sorafenib an improved disease control rate in patients using the antidiabetic drug metformin. Consistent with this, sorafenib and metformin act synergistically in inhibiting cellular proliferation in NSCLC in vitro and in vivo. A synergistic effect of both drugs is also seen on phosphorylation of the AMPKα activation site. Our results provide a rationale for the synergistic antiproliferative effects, given that AMPK inhibits downstream mTOR signaling. These data suggest that the combination of sorafenib with AMPK activators could have beneficial effects on tumor regression by AMPK pathway activation. The combination of metformin or other AMPK activators and sorafenib could be tested in prospective clinical trials. AIM: To investigate the role of sorafenib (SFN) in autophagy of hepatocellular carcinoma (HCC). We evaluated how SFN affects autophagy signaling pathway in human HCC cell lines. METHODS: Two different human HCC cell lines, Hep3B and Huh7, were subjected to different concentrations of SFN. Cell viability and onset of apoptosis were determined with colorimetric assay and immunoblotting analysis, respectively. The changes in autophagy-related proteins, including LC3, ULK1, AMPK, and LKB, were determined with immunoblotting analysis in the presence or absence of SFN. To assess autophagic dynamics, autophagic flux was measured with chloroquine, a lysosomal inhibitor. The autophagic responsiveness between different HCC cell lines was compared under the autophagy enhancing conditions. RESULTS: Hep3B cells were significantly more resistant to SFN than Huh7 cells. Immunoblotting analysis revealed a marked increase in SFN-mediated autophagy flux in Huh7 cells, which was, however, absent in Hep3B cells. While both starvation and rapamycin enhanced autophagy in Huh7 cells, only rapamycin increased autophagy in Hep3B cells. Immunoblotting analysis of autophagy initiation proteins showed that SFN substantially increased phosphorylation of AMPK and consequently autophagy in Huh7, but not in Hep3B cells. CONCLUSION: The autophagic responsiveness to SFN is distinct between Hep3B and Huh7 cells. Resistance of Hep3B cells to SFN may be associated with altered autophagy signaling pathways.

What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?

The fusion protein BCR-ABL

Chronic myeloid leukemia (CML) is a clonal hematopoietic stem cell disorder characterized by Philadelphia chromosome and resultant production of the constitutively activated BCR-ABL tyrosine kinase. Imatinib (STI571), selective inhibitor of the ABL-tyrosine kinase, inhibits the activity of BCR-ABL tyrosine kinase. A phase I and II study of STI571 showed remarkable cytogenetic effect in patients with interferon-refractory CML, offering new hope for therapy for CML. It will, however, require long-term follow-up data from phase II and III clinical studies to validate the effect of STI571 on survival. As therapy for CML improves, monitoring minimal residual disease will be important. BACKGROUND: Chronic myelogenous leukemia (CML) is caused by the BCR-ABL tyrosine kinase, the product of the Philadelphia chromosome. Imatinib mesylate, formerly STI571, is a selective inhibitor of this kinase. METHODS: A total of 532 patients with late--chronic-phase CML in whom previous therapy with interferon alfa had failed were treated with 400 mg of oral imatinib daily. Patients were evaluated for cytogenetic and hematologic responses. Time to progression, survival, and toxic effects were also evaluated. RESULTS: Imatinib induced major cytogenetic responses in 60 percent of the 454 patients with confirmed chronic-phase CML and complete hematologic responses in 95 percent. After a median follow-up of 18 months, CML had not progressed to the accelerated or blast phases in an estimated 89 percent of patients, and 95 percent of the patients were alive. Grade 3 or 4 nonhematologic toxic effects were infrequent, and hematologic toxic effects were manageable. Only 2 percent of patients discontinued treatment because of drug-related adverse events, and no treatment-related deaths occurred. CONCLUSIONS: Imatinib induced high rates of cytogenetic and hematologic responses in patients with chronic-phase CML in whom previous interferon therapy had failed. Molecular abnormalities caused by the hybrid Bcr-Abl gene are causally associated with the development and progression of Philadelphia chromosome-positive (Ph(+)) chronic myelogenous leukemia (CML). Imatinib mesylate (STI571), a specific Bcr-Abl tyrosine-kinase signal-transduction inhibitor, has shown encouraging activity in phase I and II studies of CML. Here, we describe the use of imatinib mesylate to treat 75 patients in blast-phase CML (median age, 53 years; 65 with nonlymphoid and 10 with lymphoid blasts), and compare the results with those of a historical control group treated with standard cytarabine-based therapy. Imatinib mesylate was given as oral doses at 300 to 1000 mg per day and was the first salvage therapy for 47 patients. The objective response rate was 52% (39 of 75 patients: 16 had complete and 3 had partial hematologic response; 12 had hematologic improvement; 7 returned to second chronic phase; and 1 had a complete response in extramedullary blastic disease). Response rates were not different between nonlymphoid and lymphoid groups. The cytogenetic response rate was 16% (12 patients: 5 complete, 3 partial [Ph(+) below 35%], and 4 minor [Ph(+), 34% to 90%]). The estimated median overall survival was 6.5 months; the estimated 1-year survival was 22%. Response to therapy (landmark analysis at 8 weeks) was associated with survival prolongation. Compared with standard cytarabine combinations, imatinib mesylate therapy was less toxic and produced a higher response rate (55% versus 29%, P =.001), longer median survival (7 versus 4 months, P =.04), and lower 4-week induction mortality (4% versus 15%, P =.07). Imatinib mesylate is currently being tested in combination with other drugs to improve the prognosis for blast-phase CML. Chronic myeloid leukaemia (CML) is characterised by the occurrence of the Philadelphia (Ph) chromosome (9/22 translocation) and the formation of a fusion protein--the BCR-ABL transcript with constitutive activation of the BCR-ABL tyrosine kinase and consequent changes in the intracellular signal transduction, which is responsible for the deregulated myeloid cell proliferation. STI571 (signal transduction inhibition number 571) is a potent and selective inhibitor of the BCR-ABL tyrosine kinase. In the chronic phase of the disease, normal peripheral blood values are achieved within the first month of treatment in the large majority of patients and in many patients also a cytogenic response within the following months. The results in the advanced phase are far less favourable, which is explained by the development of resistance owing to reactivation of the BCR-ABL signal transduction. Side effects are primarily nausea, vomiting, various rashes, oedema, most often in the periorbital region, and musculoskeletal symptoms, including muscle cramps. Perspectives for treatment with STI571 are described, as are combinations with alpha-interferon and other cytostatics with a synergistic profile. The translocation (9;22) gives rise to the p190(Bcr-Abl) and p210(Bcr-Abl) tyrosine kinase proteins, considered sufficient for leukemic transformation. Philadelphia-positive (Ph(+)) acute leukemia patients failing to respond to initial induction therapy have a poor prognosis with few effective treatment options. Imatinib is an orally administered, potent inhibitor of the Bcr-Abl tyrosine kinase. We conducted a clinical trial in 56 patients with relapsed or refractory Ph(+) acute lymphoblastic leukemia (ALL; 48 patients) or chronic myelogenous leukemia in lymphoid blast crisis (LyBC; 8 patients). Imatinib was given once daily at 400 mg or 600 mg. Imatinib induced complete hematologic responses (CHRs) and complete marrow responses (marrow-CRs) in 29% of ALL patients (CHR, 19%; marrow-CR, 10%), which were sustained for at least 4 weeks in 6% of patients. Median estimated time to progression and overall survival for ALL patients were 2.2 and 4.9 months, respectively. CHRs were reported for 3 (38%) of the patients with LyBC (one sustained CHR). Grade 3 or 4 treatment-related nonhematologic toxicity was reported for 9% of patients; none of the patients discontinued therapy because of nonhematologic adverse reactions. Grade 4 neutropenia and thrombocytopenia occurred in 54% and 27% of patients, respectively. Imatinib therapy resulted in a clinically relevant hematologic response rate in relapsed or refractory Ph(+) acute lymphoid leukemia patients, but development of resistance and subsequent disease progression were rapid. Further studies are warranted to test the effects of imatinib in combination with other agents and to define the mechanisms of resistance to imatinib. Chronic myelogenous leukemia (CML) is characterized by the presence of a Bcr-Abl fusion protein with deregulated tyrosine kinase activity that is required for maintaining the maligt phenotype. Imatinib, a selective inhibitor of Bcr-Abl, induces major cytogenetic remission (MCR) or complete cytogenetic remission (CCR) in the majority of patients with CML in first chronic phase. However, thorough re-evaluation of cytogenetics in a cohort of patients in MCR or CCR demonstrated clonal karyotypic abnormalities in more than 10% of cases, some of which were clinically associated with a myelodysplastic syndrome (MDS). Further analysis identified previous exposure to cytarabine and idarubicin as significant risk factors for the subsequent occurrence of abnormalities in Philadelphia chromosome-negative (Ph-) cells. To investigate if cytogenetically normal but clonal hematopoiesis might be present in other patients in cytogenetic remission, we studied X-chromosome inactivation as a marker of clonality by polymerase chain reaction analysis of the human androgen receptor (HUMARA). We find that imatinib restores a polyclonal pattern in most patients in CCR and MCR. Nonetheless, our results are consistent with the notion that targeted therapy of CML with imatinib favors the manifestation of Ph- clonal disorders in some patients. They indicate that patients on imatinib should be followed with conventional cytogenetics, even after induction of CCR. Imatinib mesylate (STI571, Glivec, Gleevec) is a powerful inhibitor of the tyrosine kinase activity of Bcr-Abl, the oncoprotein responsible for chronic myeloid leukemia (CML). The drug shows great efficacy in chronic phase, but is less effective in maintaining hematologic remissions in blast crisis patients. Our group has previously described several cell lines made resistant to imatinib. We now examine the question of cross-resistance to other chemotherapeutic drugs used in CML. Four paired imatinib-sensitive/resistant CML cell lines were assessed by caspase-3 and MTS assays for their proliferative response to cytosine arabinoside (Ara-C), daunorubicin (DNR), homoharringtonine (HHT) and hydroxyurea (HU), either alone or in combination with imatinib. Primary blasts from advanced-stage CML patients refractory to imatinib therapy were studied by semi-solid media clonogenic assays. We found that these drugs are generally capable of major inhibition of proliferation of the CML cell lines, although differential responses to DNR and HHT were noted between some sensitive and resistant cell line pairs, implying that resistance to imatinib may confer a growth advantage under such conditions. The four drugs were also effective in preventing the formation of progenitor cell colonies from CML patients both before treatment with imatinib, and after relapse on the drug. Isobolographic analysis implied that these drugs will generally combine well with imatinib, and in some cases will be synergistic. We conclude that Ara-C, DNR or HHT, either alone or in combination with imatinib, are likely to be the best therapeutic alternatives in the management of patients who become resistant to imatinib monotherapy. Imatinib mesylate (Glivec) is a selective inhibitor of bcr-abl tyrosine kinase, the product of the Philadelphia chromosome, which is the hallmark of chronic myeloid leukaemia (CML). With imatinib, complete cytogenetic response (CCR) can be achieved in over 70% of newly diagnosed patients with CML. However, the optimal long-term management of patients who achieve CCR after imatinib is unknown. With longer follow-up, it is anticipated that some patients are likely to progress and become candidates for autologous transplantation. We studied filgrastim (r-metHuG-CSF) mobilisation of peripheral blood stem cells (PBSC) in 32 patients who have achieved CCR with imatinib. Our data demonstrate that (1) the target CD34(+) cell yields of >/=2.0 x 10(6)/kg were attained with filgrastim 10 microg/kg/day, in 9/18 (50%) of patients during uninterrupted imatinib therapy, and in 10/14 (70%) when imatinib was temporarily withheld. The median CD34(+) cell yield per aphaeresis was 0.70 x 10(6)/kg (range 0.14-2.18) and 2.90 x 10(6)/kg (range 0.15-8.71) in the two groups, respectively (P&<0.005). (2) The cell yields did not correlate with the duration of imatinib administration. (3) There was no impact of the mobilisation procedure on the level of leukaemia as measured by serial blood bcr-abl levels using real-time quantitative PCR with either protocol. (4) bcr-abl remained detectable at low levels in the harvests in most but not all patients. In conclusion, filgrastim can safely be used to mobilise PBSC in patients who have achieved CCR with imatinib, but CD34(+) cell yields are significantly improved when imatinib is temporarily withheld. The Philadelphia chromosome translocation (t(9;22)) results in the molecular juxtaposition of two genes, BCR and ABL, to form an aberrant BCR-ABL gene on chromosome 22. BCR-ABL is critical to the pathogenesis of chronic myelogenous leukemia and a subset of acute leukemias. The chimeric Bcr-Abl protein has constitutively elevated tyrosine phosphokinase activity. This abnormal enzymatic activation is critical to the oncogenic potential of Bcr-Abl. Initially, protein kinases were thought to be poor therapeutic targets because of their ubiquitous nature and crucial role in many normal physiologic processes. However, the advent of imatinib mesylate (Gleevec, Novartis Pharmaceuticals, Basel, Switzerland), formerly known as STI571 and CGP57148B, demonstrated that designer kinase inhibitors could be specific. This agent has shown striking activity in chronic myelogenous leukemia. It also inhibits phosphorylation of Kit (stem-cell factor receptor) and platelet-derived growth factor receptor. In addition, it has shown similar impressive responses, with little host toxicity, in gastrointestinal stromal tumors, which harbor activating Kit mutations, and in tumors with activated platelet-derived growth factor receptor. The studies of imatinib mesylate provide proof-of-principle for using aberrant kinases as a therapeutic target and are a model for the promise of molecular therapeutics. This paper reviews the current knowledge on the function of Bcr-Abl and its normal counterparts (Bcr and Abl), as well as the impact of this knowledge on the development of a remarkably successful targeted therapy approach. Chronic myeloid leukemia (CML) is arguably the best understood of all human maligcies. Its origins in the hematopoietic stem cell can be traced to a reciprocal translocation involving chromosomes 9 and 22, dubbed the Philadelphia chromosome, which is observed in essentially all patients. The resulting fusion gene, BCR/ABL, encodes an activated tyrosine kinase that can act alone to induce a CML-like syndrome in mouse models. These animal models have validated BCR/ABL as a target for the development of specific pharmaceutical inhibitors. The kinase inhibitor imatinib mesylate (Gleevec) is highly specific, effective, and minimally toxic, but may not effect cures as a single agent, particularly in patients with accelerated and blast-phase disease. Resistance to imatinib can confound therapy. Surprisingly, a high percentage of resistant cases manifest intact or augmented BCR/ABL signaling, suggesting that this oncoprotein, or signaling pathways emanating from it, remain viable targets. Combination chemotherapy is under active investigation, and among the most compelling strategies is dual treatment with agents that both target BCR/ABL signal transduction. BCR/ABL activates Ras, and compounds designed to antagonize Ras function called farnesyl transferase inhibitors (FTIs) have shown potent activity in vitro and in animal models of BCR/ABL-induced leukemia. Initial clinical trials in patients with refractory acute myeloid leukemia and CML in blast crisis have shown significant activity, suggesting that trials combining imatinib and FTIs are warranted. PURPOSE: Imatinib mesylate is a tyrosine kinase inhibitor with high affinity for the BCR-ABL fusion protein expressed by the hematopoietic cells in chronic myelogenous leukemia (CML). Some patients with chronic-phase or accelerated-phase CML either relapse after an initial response or are refractory to imatinib, prompting us to evaluate the efficacy of dose increase in such patients. EXPERIMENTAL DESIGN: Twelve chronic-phase patients initially receiving 400 mg/day and 4 patients with accelerated phase initially receiving either 400 mg/day (two patients) or 600 mg/day (two patients) had their dose increased (14 to 800 mg/day and 2 to 600 mg/day) because of progressive disease (usually clonal evolution) or inadequate cytogenetic response after at least 1 year of therapy. RESULTS: Six patients had major cytogenetic responses after dose increase (3 complete and 3 partial). Two others had minor cytogenetic responses. Two patients with clonal evolution transiently lost the additional clonal aberrations. Almost all of the responses occurred within 6 months, and were typically 3-6 months in duration. However, 3 patients have continuing major cytogenetic responses of >18 months duration. Dose increase was well tolerated, with thrombocytopenia, mild leukopenia, and exacerbation of prior edema being the most common adverse events. CONCLUSIONS: Although increasing the dose of imatinib can benefit a subgroup of patients with CML with either an inadequate cytogenetic response or disease progression, our results suggest the majority will not have a sustained meaningful response, and that other options, such as allogeneic stem cell transplant or investigational therapies, also need to be considered at the time of dose increase. Chronic myeloid leukemia (CML) is characterized by the Philadelphia translocation that fuses BCR sequences from chromosome 22 upstream of the ABL gene on chromosome 9. The chimerical Bcr-Abl protein expressed by CML cells has constitutive tyrosine kinase activity, which is essential for the pathogenesis of the disease. Imatinib, an ATP-competitive selective inhibitor of Bcr-Abl, has unprecedented efficacy for the treatment of CML. Most patients with early stage disease achieve durable complete hematological and complete cytogenetic remissions, with minimal toxicity. In contrast, responses are less stable in patients with advanced CML. This review highlights the pathogenesis of CML, its clinical features, and the development of imatinib as a specific molecularly targeted therapy. Aspects of disease monitoring and side effects are covered as well as resistance to imatinib and strategies to overcome resistance, such as alternative signal transduction inhibitors and drug combinations. Perspectives for further development are also discussed. The Philadelphia chromosome found in leukemia cells of chronic myelogenous leukemia (CML) patients is produced by translocation between chromosomes 9 and 22, resulting in expression of a chimera protein of Bcr and Abl kinase in the cytoplasm. Bcr-Abl kinase attracted oncology researchers as a molecular target for CML therapy, and a variety of small Abl kinase inhibitors were synthesized. STI571 (imatinib mesylate) was produced by modification of 2-phenylaminopyrimidine, a core structure of protein kinase C inhibitor, to improve selectivity, stability, solubility, and bioavailability. STI571 competitively binds to the ATP binding site of Bcr-Abl kinase and inhibits Abl tyrosine kinase activity. STI571 showed significant efficacy in the clinical study with CML patients at all stages: chronic phase, accelerated phase, and blast crisis. More than 90% of the patients showed good hematologic response to STI571. STI571 is also a potent inhibitor of a receptor-type c-Kit tyrosine kinase. Therefore, STI571 was examined for therapeutic efficacy against maligt Gastro-Intestinal Stromal Tumors (GIST), which are mainly caused by aberrant expression of a mutated c-Kit that is constitutively active without binding of a ligand, stem cell factor (SCF). More than a half of the metastatic GIST patients enrolled in the clinical study responded to STI571. Thus, STI571 is now used as a therapeutic drug for both CML and GIST in more than 80 countries worldwide. Certain point mutations in the ATP binding site were found to be a cause of resistance to STI571 in both Bcr-Abl and c-Kit kinases. Therefore, it would be better to make a precise therapeutic strategy with STI571 based on the gene analysis data. It is also expected that it will be possible to design an inhibitor to overcome such resistance by using the structural information on the mutants. Imatinib mesylate (IM) binds to the BCR-ABL protein, inhibiting its kinase activity and effectively controlling diseases driven by this kinase. IM resistance has been associated with kinase mutations or increased BCR-ABL expression. However, disease progression may be mediated by other mechanisms that render tumor cells independent of BCR-ABL. To demonstrate this potential, IM-resistant cells were found in chronic myelogenous leukemia patients with continuous BCR-ABL gene expression but undetectable BCR-ABL protein expression. These cells were unresponsive to IM and acquired BCR-ABL-independent signaling characteristics. IM resistance in some patients may be mediated through loss of kinase target dependence. Imatinib mesylate is a new drug that can inhibit the tyrosine kinase activity of Bcr-Abl, the receptors for platelet-derived growth factor receptor(PDGF) and stem cell factor, or c-kit. Chronic myeloid leukemia (CML) is distinguished by the presence of a reciprocal translocation between chromosomes 9 and 22 that results in a shortened chromosome 22, termed the Philadelphia(Ph) chromosome. As a result of the translocation, a fusion gene called the Bcr-Abl gene is created from two normal cellular genes, encoding a chimeric Bcr-Abl protein with a deregulated tyrosine kinase activity. The expression of Bcr-Abl tyrosine kinase has been shown to be necessary and sufficient for the transformed phenotype of CML cells. Imatinib can block the kinase activity of Bcr-Abl, thus inhibiting the proliferation of Ph-positive progenitors, and has shown activity against all phases of CML, though responses are most substantial and durable in patients in the chronic phase. An international phase III study which compared the efficacy of imatinib with that of interferon alpha combined with low-dose cytarabine in newly diagnosed chronic-phase CML showed the rate of major cytogenetic response at 24 months was 90%, including 82% of complete cytogenetic response. These results indicated that imatinib was superior to interferon-containing treatment as a first-line therapy. More than 10,000 patients worldwide, including those in Japan, have been treated with imatinib in clinical trials, and a lot of information has been accumulated on the use of this drug. The aim of this article is to review the use of this drug and the practical management of patients with chronic myeloid leukemia. Chronic Myeloid Leukemia (CML) has always been an ideal model to understand the molecular pathogenesis of human leukaemias and the way to cure them. This can be ascribed to the fact that CML was the first human cancer demonstrated to be strongly associated to the presence of a recurrent chromosomal translocation (the t(9;22)(q34;q11) that creates the Philadelphia (Ph)-chromosome) and to a specific molecular defect, the formation of a hybrid BCR-ABL gene that generates new fusion proteins endowed with a constitutive tyrosine-kinase (TK) activity, strongly implicated in the pathogenesis of the disease. The introduction into clinical practice of imatinib, (Glivec, Gleevec, Novartis), a potent tyrosine kinase inhibitor of the Bcr-Abl protein as well as of a restricted number of other TKs, has not only produced a substantial improvement in the treatment of CML, but represents a major break-through in the perspective of opening a new era, that of molecularly targeted therapy, in the management of other types of leukemia, lymphoma and cancer in general. Chronic myelogenous leukemia (CML) is a clonal hematopoietic disorder caused by the reciprocal translocation between chromosome 9 and 22. As a result of this translocation, a novel fusion gene, BCR-ABL, is created on Philadelphia (Ph) chromosome, and the constitutive activity of the BCR-ABL protein tyrosine kinase plays a critical role in the disease pathogenesis. Imatinib mesylate, a selective BCR-ABL tyrosine kinase inhibitor, was first given to a patient with CML in June 1998. Since then, it has continued to demonstrate remarkable efficacy in treating patients with CML. Based upon the results of early phase I and II studies, a phase III study (IRIS Study) that was randomized to first-line imatinib (400 mg/day) or to standard treatment with interferon+low-dose Ara-C, was conducted on 1,106 patients newly diagnosed (within 6 months) with chronic-phase CML. After median follow-up of 30 months, imatinib showed significantly superior tolerability, hematologic and cytogenetic responses (major cytogenetic response, 90%; complete cytogenetic response, 82%), and overall survival (95% without censoring allo-HSCT). Although imatinib is the first-line therapy and has changed the paradigm of CML treatment strategy, questions remain as to the meaning of cytogenetic and molecular response, curability, optimal dose, and relation with allo-HSCT. Imatinib mesylate was designed as an inhibitor targeting the BCR-ABL tyrosine kinase, the molecular counterpart of the Philadelphia translocation t(9;22)(q34;q11). We report on a patient with chronic myeloid leukemia (CML) undergoing acceleration during imatinib treatment. Cytogenetic analysis revealed four different cell populations: 46,XX,t(9;22)(q34;q11),der(18)t(2;18)(p11;p11)[1]/47,idem,i(17)(q10),-der(18)t(2;18),+der(22)t(9;22)[1]/46,idem,-t(9;22),der(9)t(9;22),ider(22)t(9;22)[12]/ 47,idem,-t(9;22),der(9)t(9;22),+22,ider(22)t(9;22)x2[1]. FISH analysis confirmed the presence of these four clones. Moreover, 49% of the interphase nuclei contained either one or two clustered fusion signals, indicating a low-level amplification of the BCR-ABL fusion gene. With quantitative real-time RT-PCR, a BCR-ABL/G6PDH ratio of 0.8 was determined, which is comparable to that measured in the K562 cell line with a known BCR-ABL amplification and which is increased by more than about 60-fold compared to a CML at diagnosis with >80% Philadelphia-positive cells. We give further evidence that the genomic BCR-ABL amplification results in an increased level of BCR-ABL transcript linking two potent mechanisms of resistance against imatinib treatment. Chronic myeloid leukemia cells contain a BCR-ABL oncoprotein with an enhanced tyrosine kinase activity, which is considered to be the principal 'cause' of the leukemia. Though the precise mechanisms underlying the leukemogenesis remains enigmatic, the use of imatinib to inhibit the dysregulated kinase activity has proved remarkably successful in clinical practice. Imatinib was the first small molecule developed to inhibit BCR-ABL tyrosine kinase activity and its success introduced the current era of molecularly targeted therapies for a number of other maligcies. In patients with chronic myeloid leukaemia who develop resistance to imatinib, the Bcr-Abl signaling pathway is often re-established. This has led to the emergence of a number of alternative treatment strategies designed to target the leukemic cell which are resistant to imatinib. Chronic myeloid leukemia (CML) originates from the hematopoietic stem cell and is characterized by the reciprocal translocation t(9;22)(q34;q11), which results in the BCR-ABL fusion gene on chromosome 22q-, also known as the Philadelphia chromosome. This chimeric gene codes for a cytoplasmic protein with constitutive tyrosine-kinase activity, responsible for cellular transformation and leukemogenesis in CML. The aim of this observational cohort study was to discriminate and quantify BCR-ABL transcripts in the peripheral blood of patients with CML who were treated with imatinib mesylate (Glivec, Novartis). Twenty-two patients were followed for six months during treatment. Quantitative real time polymerase chain reaction was performed before treatment and after 3 and 6 months from treatment initiation. As compared with the third month, there was a significant decrease in BCR-ABL expression in the sixth month of treatment (P = 0.0002). At the sixth month, there was a significant difference in the levels of the two major transcripts of BCR-ABL, B2A2 and B3A2 (P = 0.0347), indicating that B2A2 may be more sensitive to imatinib. The results of our study indicate that imatinib is able to modify the natural history of CML, and raise the hypothesis that patients who express the B2A2 transcript may have a better prognosis. Chronic myelogenous leukemia is characterized by the Philadelphia-chromosome, a shortened chromosome 22 which is the result of a reciprocal translocation between chromosome 9 and 22. The fusion gene is called BCR-ABL. After transcription and translation the constitutively activated p210 BCR-ABL oncoprotein is formed. This leads to uncontrolled activation of the ABL tyrosin kinase. Deregulated cellular proliferation and diminished apoptosis of BCR-ABL transformed cells is the result. Expression of the BCR-ABL oncoprotein is sufficient and necessary for the development of a CML phenotype. Imatinib mesylate (Glivec) is a small molecule that binds to the ATP pocket of ABL and blocks downstream signalling events. Imatinib is very effective in the treatment of CML in all stages of the disease. Patients with newly diagnosed chronic phase CML were randomized to imatinib or to interferon plus cytarabine in the IRIS trial. Imatinib showed significantly superior tolerability, hematologic and cytogenetic resposes and increased time to progression. In patients with advanced phase CML, imatinib is less effective and response duration is short. Median overall survival of blast crisis patients is 6.9 months only. Additional BCR-ABL independent chromosomal abnormalities are common in advanced phase CML and result in resistance to imatinib. BCR-ABL kinase-domaine mutations are frequently found in imatinib resistant patients and confer diminished sensitivity to imatinib. Second generation, more powerful ABL kinase inhibitors, which are effective against most of the known mutations are currently tested in clinical trials. Chronic myeloid leukemia (CML) is characterized by the presence of a BCR-ABL fusion gene, which is the result of a reciprocal translocation between chromosomes 9 and 22, and is cytogenetically visible as a shortened chromosome 22 (Philadelphia). Research during the past two decades has established that BCR-ABL is probably the pathogenetic pathway leading to CML, and that constitutive tyrosine kinase activity is central to BCR-ABL capacity to transform hematopoietic cells in vitro and in vivo. The tyrosine kinase inhibitor imatinib mesylate was introduced into the treatment regimen for CML in 1998. During the last few years, reports on chromosomal changes during imatinib treatment have been described. In this study, we evaluated the random aneuploidy rate with chromosomes 9 and 18 in bone marrow from treated and untreated patients. We found higher aneuploidy rates in both treated and untreated patients compared to the control group. In three patients who were treated with imatinib mesylate for more than 1.5 years, triploidy also appeared in some nuclei. To our knowledge, this is the first report on new chromosomal changes such as random aneuploidy and triploidy under imatinib treatment, but more studies are needed to investigate the long-term effect of the imatinib treatment on genetic instability. Philadelphia (Ph) chromosome is the cytogenetic hallmark of chronic myeloid leukemia (CML). The translocation forms a chimeric gene, bcr-abl, which generates BCR-ABL. This fusion protein constitutively activate ABL tyrosine kinase and causes CML. Imatinib mesylate is a selective tyrosine kinase inhibitor on ABL, c-Kit and PGDF-receptor, and functions through competitive inhibition at the ATP-binding site of the enzyme, which leads to growth arrest or apoptosis in cells that express BCR-ABL. Imatinib has revolutionized the management of patients with CML, and at a dose of 400 mg daily has become the current standard therapy for newly diagnosed patients with CML even when they have HLA-matched family donors. Although imatinib therapy has only a 5-year history, it is hoped that CML will be cured with this drug and with forthcoming second-generation tyrosine kinase inhibitors as well as by allogeneic stem cell transplantation in patients who have become resistant to these drugs. Imatinib mesylate, binding to the inactive conformation of Bcr-Abl tyrosine kinase and suppressing the Ph chromosome positive clone, has revolutionized the treatment of chronic myeloid leukaemia (CML) patients. Given the high rates of clinical and cytogenetic remission achieved, the molecular monitoring of BCR-ABL transcript levels by RT-qPCR has become always more important to assess minimal residual disease. Recently, recommendations for harmonizing current methodologies for detecting and measuring BCR-ABL transcripts in CML patients have been suggested. Studies of imatinib-treated patients have determined that the BCR-ABL levels measured early in therapy may predict durable cytogenetic remission and in turn prolonged progression free-survival or acquisition of resistance. The major mechanism of imatinib resistance is clonal expansion of leukaemia cells with mutations in the Bcr-Abl fusion tyrosine kinase. The early reduction of such mutations may allow timely treatment intervention to prevent or overcome resistance. We review current trends in the management of chronic myeloid leukaemia patients undergoing treatment with tyrosine kinase inhibitors. Imatinib is one of the most recent medications used for the treatment of chronic myeloid leukemia (CML) and gastrointestinal stromal tumor (GIST). It is an orally administered protein-tyrosine kinase inhibitor, an enzyme which is produced by BCR-ABL fusion which results from translocation of 9:22 chromosome (Philadelphia chromosome). Imatinib blocks proliferation and induces apoptosis of BCR-ABL-expression in CML. Many side effects produced by imatinib have been documented but its induction of hepatotoxcity has been rarely reported. Only a few cases so far have been reported in the literature and almost all were in females. We describe another case of hepatotoxicity due to imatinib in a 17-year old female with clinical, laboratory and histopathological changes. The case described here suggests that imatinib may also induce immune hepatitis, in some patients. Chronic myeloid leukemia (CML) is caused by Bcr-Abl, a constitutively active tyrosine kinase that is the result of a reciprocal translocation between chromosomes 9 and 22 and cytogenetically evident as the Philadelphia chromosome. Imatinib (Glivec, Gleevec), a specific small molecule inhibitor of Bcr-Abl, has become the standard drug therapy for CML, and has dramatically diminished the use of allogeneic stem cell transplantation. Despite unprecedented rates of complete cytogenetic response, residual disease remains detectable in the majority of patients, suggesting that imatinib fails to eradicate leukemic stem cells. In this publication, the current perspectives for CML patients treated with imatinib are reviewed, focusing on the results of both standard and high-dose therapy. Monitoring of time-dependent prognostic factors is reviewed. The reasons imatinib may not be able to eradicate the disease are discussed, and potential strategies to achieve disease elimination are presented. Lastly, resistance to imatinib and the potential of second-generation Abl kinase inhibitors in the setting of clinical resistance are considered. Chronic myelogenous leukemia (CML) is a progressive and often fatal hematopoietic neoplasm characterized by the presence of the Philadelphia chromosome. This arises from a balanced translocation between chromosomes 9 and 22, creating the bcr-abl fusion gene. It is often stated that the only proven curative option is allogeneic stem cell transplantation, which is indicated for only a limited subset of patients. The Bcr-Abl tyrosine kinase inhibitor imatinib represented a major advance over conventional CML therapy. After imatinib treatment, > 90% of patients had a complete hematologic response, and 70%-80% had a complete cytogenetic response. With 5 years of follow-up, the data are very encouraging and exhibit a major change in the natural history of the disease. The understanding of some of the mechanisms of resistance to imatinib has led to a rapid development of new agents that might overcome this resistance. The outlook today for patients with CML is much brighter than that of a few years ago. Chronic myeloid leukemia (CML) is characterized by the presence of the Philadelphia chromosome, which is associated with a balanced translocation involving chromosomes 9 and 22 to produce a fusion gene (bcr-abl) that gives rise to a constitutively activated Abl tyrosine kinase. This kinase led to the discovery of several small-molecule inhibitors, imatinib being the first and most successful of these. Resistance to imatinib results in some patients from Abl kinase point mutations. Overcoming imatinib resistance represents one of the biggest challenges facing clinicians in the modern management of CML. In this review, we discuss the current understanding of CML pathophysiology and mechanisms of imatinib resistance and how advancing this knowledge has led to the design of novel therapies in the area of blastic phase CML and Philadelphia chromosome-positive acute lymphoblastic leukemia with previous imatinib failure. BACKGROUND: Chronic myeloid leukemia (CML) is a hematopoietic stem cell cancer driven by the BCR-ABL fusion protein that arises from the translocation of chromosomes 9 and 22. The disease begins with an indolent chronic phase (CP) that can last for 3 to 5 years. If untreated, it progresses into accelerated phase (AP) and within a year, blast phase (BP). Survival at this point is less than 1 year. during disease progression, mutations and the Philadelphia chromosome (Ph) appear (a process called clonal evolution). The only known curative therapy for CML is allogeneic bone marrow transplant (BMT). However, toxicity is formidable, with treatment- related mortality reported in the 30% range. Thus, effective therapy that maintains the patient with CML in CP with minimal toxicity is the goal for treatment of modern therapies. Because the preeminent mutation driving CML is BCr-ABL, therapies targeting BCR-ABL are the logical choice for disease-specific therapy. BCR-ABL inhibitors, such as imatinib, are proof that targeting specific genetic mutations associated with cancer yields a high degree of efficacy with minimal toxicity. OBJECTIVE: This review will outline the evolution of therapy in CML. Preimatinib and imatinib-based treatment strategies, clinical efficacy, and the mechanism of imatinib resistance will be discussed. SUMMARY: The discovery of the Ph and, subsequently, the identification of BCr-ABL revolutionized the treatment of CML. Cytoreductive chemotherapy, such as busulfan and hydroxyurea, was a mainstay of therapy to control white blood cell (WBC) counts; however, it did not modify the progression of the disease to AP and BP. The overall survival with CML ranges from 45 to 58 months in patients treated with cytoreductive therapy only. Treatment was advanced with the introduction of interferon (IFn ) immunotherapy in the 1980s. In some studies, IFn produced a complete hematologic response (CHR) in more than 50% of patients; however, its nonspecific immunostimulatory mechanism also produced severe flulike symptoms that limited tolerability. despite the significant toxicity, cost, and inconvenience of injecting IFN thrice weekly, median survival ranged from 60 to 89 months. Allogeneic BMT is the only known curative therapy for CML; however, treatment-related mortality from infection, bleeding, and graft versus host disease, age, and the availability of suitable donors limits its widespread use. Imatinib functions by competing with adenosine triphosphate (ATP) for binding to the BCr-ABL tyrosine kinase. In the absence of ATP, BCR-ABL is not able to activate downstream effector tyrosine kinase molecules that drive wBC proliferation. The International randomized Interferon versus STI571 clinical trial was the first to document the efficacy of imatinib as a first-line therapy for patients in CP. More than 90% of these patients had a CHr. Toxicities associated with this therapy are low. response in patients with advanced CML is less pronounced than in CP and is shorter lived, with less than 30% of patients achieving a CHR. For patients with CML in BP, the only viable therapy is to attempt a temporary reduction in disease burden with a salvage chemotherapy regimen, such as VAC (etoposide, cytarabine, and carboplatin). The goal of this induction chemotherapy is to induce a second remission; then the patient may be considered for allogeneic BMT. The main toxicities seen with imatinib therapy are myelosuppression, edema, and myalgia/arthralgia. In many cases, imatinib dosage can be briefly halted or lowered while the toxicity is managed. Imatinib resistance may develop at any time and inevitably leads to disease progression. resistance is usually caused by mutations within BCr-ABL, decreasing the affinity of imatinib binding. next-generation kinase inhibitors are focused on the ability to inhibit these mutated forms of BCR-ABL. CONCLUSION: For the majority of patients with CML in CP, the standard of care is to maintain the patient in CP with imatinib therapy. Clinical trials have been extraordinarily successful, with 5-year survival rates greater than 90%. Allogeneic BMT continues to be an option for those who cannot tolerate imatinib or when CML progresses on imatinib therapy. Chronic myeloid leukemia (CML) is the first human maligcy for which the promise of targeted therapy has come true. CML is invariably associated with a specific genetic lesion--the t(9;22) chromosomal translocation. As a consequence of this translocation, a BCR-ABL fusion gene is formed on the 22q- derivative (traditionally known as the Philadelphia chromosome) and the deregulated tyrosine kinase activity of the protein encoded by this gene has been shown to be both necessary and sufficient for initiation and maintece of the disease. Imatinib mesylate, an orally available tyrosine kinase inhibitor that targets Bcr-Abl, entered clinical evaluation in 1998. Its efficacy surpassed almost everyone's predictions, and the observation of high response rates and favorable toxicity profile associated with imatinib therapy led to its approval as first-line treatment for all newly diagnosed CML patients over an exceptionally short period of time. The 6-year results of the Phase III trial have recently been reported and confirm durability of responses and declining incidence of adverse events over time, although, at present, occurrence of unexpected side effects in the long term cannot be excluded. Although imatinib does not 'cure' CML and has to be administered chronically to patients, it has revolutionized both outcome and quality of life of CML patients. Throughout its history, chronic myeloid leukemia (CML) has set precedents for cancer research and therapy. These range from the identification of the first specific chromosomal abnormality associated with cancer to the development of imatinib as a specific, targeted therapy for the disease. The successful development of imatinib as a therapeutic agent for CML can be attributed directly to decades of scientific discoveries. These discoveries determined that the BCR-ABL tyrosine kinase is the critical pathogenetic event in CML and an ideal target for therapy. This was confirmed in clinical trials of imatinib, with imatinib significantly improving the long-term survival of patients with CML. Continuing in this tradition of scientific discoveries leading to improved therapies, the understanding of resistance to imatinib has rapidly led to strategies to circumvent resistance. Continued studies of hematologic maligcies will allow this paradigm of targeting molecular pathogenetic events to be applied to many additional hematologic cancers. Chronic myeloid leukemia (CML) is characterized by the presence of the Philadelphia (Ph) chromosome, which results from a reciprocal translocation between the long arms of the chromosomes 9 and 22 t(9;22)(q34;q11). This translocation creates two new genes, BCR-ABL on the 22q- (Ph chromosome) and the reciprocal ABL-BCR on 9q-. The BCR-ABL gene encodes for a 210-kD protein with deregulated tyrosine kinase (TK) activity, which is crucial for maligt transformation in CML. The recognition of the BCR-ABL gene and corresponding protein led to the synthesis of small-molecule drugs, designed to interfere with BCR-ABL tyrosine kinase activation by competitive binding at the ATP-binding site. The first tyrosine kinase inhibitor (TKI), introduced into clinical practice in 1998, was imatinib mesylate. Imatinib became the first choice drug in chronic phase CML, because of its high efficacy, low toxicity and ability to maintain durable hematological and cytogenetic responses. However, approximately 20-25% of patients initially treated with imatinib will need alternative therapy, due to drug resistance, which is often caused by the appearance of clones expressing mutant forms of BCR-ABL. Second-generation TKIs have provided new therapeutic option for the patients resistant to imatinib. Dasatinib is the first, second-generation TKI, approved in the US and European Union for the treatment of CML patients with imatinib resistance or intolerance. This drug is a dual SRC-ABL kinase inhibitor, active in most clinically relevant BCR-ABL mutations, except highly resistant T315I. Other second-generation TKIs include nilotinib, bosutinib and INNO 406. Apart from TKIs, the promising group of molecules is inhibitors of Aurora family of serine-threonine kinases. One of these molecules, MK0457, has entered clinical trials, and initial reports indicate that this compound could be active in disease associated with T315I mutation. Thus, wide spectrum of new agents, with different mode of action, is currently in clinical development for CML. It is likely that combination therapy will be the best therapeutic strategy in the future. Chronic myeloid leukemia (CML) is a paradigm for neoplasias that are defined by a unique genetic aberration, the BCR-ABL1 fusion gene. CML is also the best example for molecular target therapy. The development of protein tyrosine kinase inhibitor, imatinib, has entirely changed the strategy of therapy for CML. Nonetheless, many fields of pathogenesis for CML have not been elucidated, such as the mechanisms of blastic crisis, the causes of genetic instability including the inactivation of tumor suppressor genes, and oncogenic signaling pathways downstreams of the BCR-ABL1 fusion gene product. Herein, we review current knowledge on the molecular pathogenesis of CML. Chronic myeloid leukemia (CML) is a progressive and often fatal myeloproliferative disorder. The hallmark of CML is an acquired chromosomal translocation known as the Philadelphia chromosome (Ph) that results in the synthesis of the BCR-ABL fusion protein, a constitutively active tyrosine kinase (TK). The introduction of imatinib, a TK inhibitor (TKI) specific for BCR-ABL, was a major breakthrough in CML therapy. Although most patients respond to first-line imatinib therapy, some experience a loss of response (resistance) or require treatment discontinuation because of toxicity (intolerance). In patients for whom standard-dose imatinib therapy (400 mg/day) fails, imatinib dose escalation (600-800 mg/day) is a second-line option. However, high-dose imatinib is not an appropriate approach for patients experiencing drug toxicity, and there remain questions over the durability of responses achieved with this strategy. Alternative second-line options include the newer TKIs dasatinib and nilotinib. A substantial amount of long-term data for these agents is available. Although both are potent and specific BCR-ABL TKIs, dasatinib and nilotinib exhibit unique pharmacologic profiles and response patterns relative to different patient characteristics, such as disease stage and BCR-ABL mutational status. To optimize therapeutic benefit, clinicians should select treatment based on each patient's historical response, adverse event tolerance level, and risk factors. INTRODUCTION: Imatinib mesylate, a selective Bcr-Abl tyrosine kinase inhibitor, has proved to be most effective therapy of Philadelphia chromosome-positive chronic myelogenous leukemia. Imatinib induces complete haematological and cytogenetic response in high percentage of patients. OBJECTIVE: The aim of this study was to identify potential prognostic factors before beginning treatment with imatinib associated with complete cytogenetic response. METHODS: We analyzed 20 patients with newly diagnosed Philadelphia positive chronic myelogenous leukemia treated at our institution from June 2006 until May 2009. These patients were treated with imatinib mesylate in oral dose of 400 to 800 mg daily. Complete blood counts were performed every month, while serum chemistry evaluations and bone marrow evaluations including morphology and cytogenetics were performed every 6 months. RESULTS: Of the 20 patients analyzed in this study, 19 (95%) achieved complete haematologic response within three months. In all patients cytogenetic analyses were done and all have achieved absolute cytogenetic response. The best cytogenetic response rate at any time during study treatment among 20 patients was: complete cytogenetic response in 15, partial cytogenetic response in three and minor cytogenetic response in two patients. Among 11 observed base-line patients' characteristics five were independent predictors of a high rate of complete cytogenetic response; the absence of blasts and basophils in peripheral blood, the presence of less than 5 percent of bone marrow blasts, white blood cell count less than 10 x 10(9)/L and the absence of splenomegaly (p < 0.01). CONCLUSION: Our results showed that some pre-treatment characteristics of patients might be the cause of differences in treatment outcome. On the basis of this analysis, we identified several pre-treatment patients' characteristics to be independent prognostic factors for achievement of complete cytogenetic response. Patients with splenomegaly and abnormally high leukocyte counts were first recognized in France, Germany, and Scotland in the 1840s. The only well-documented therapy in the 19th century was use of arsenic in one or other form, which did undoubtedly reduce the leukocyte count but probably did little or nothing to prolong life. These early cases were probably examples of chronic myeloid leukemia (CML) (then called chronic granulocytic leukemia). In the 20th century important steps in unraveling the pathogenesis of CML were the discovery of the Philadelphia chromosome in 1960, and of the (9;22) translocation in 1973. There followed definition of the breakpoint cluster region on chromosome 22 in 1984 and the demonstration of the BCR-ABL transcript in CML in 1985. In the first half of the 20th century patients were treated predomitly with radiotherapy, and later on with busulfan, hydroxycarbamide, or interferon-alfa (IFN-α). From 1980 onwards allogeneic stem cell transplantation (SCT) became the treatment of choice for eligible patients. The era of tyrosine kinase inhibitors (TKI) began in 1998 and today the use of the original TKI, imatinib, has replaced SCT as initial therapy for patients who present with CML in chronic phase. BACKGROUND/AIM: Imatinib mesylate, a tyrosine kinase inhibitor with specific activity against the breakpoint cluster region--Abelson murine leukemia (BCR-ABL) tyrosine kinase has been developed for treatment of chronic myelogenous leukemia (CML). Its hematologic and cytogenetic effects have been evaluated in a series of clinical trials. The aim of this study was to report hematologic and cytogenetic response in CML patients during the treatment with imatinib mesylate. METHODS: A total of 21 patients were treated and observed from July 2006 to December 2008. The median time from CML diagnosis was no more than 12 months, so all the patients received previous treatment with hydroxyurea for which the median time was 3 months. The patients received imatinib mesylate in an effective oral dose of 400 to 800 mg daily, which was followed with peripheral blood counts, bone marrow examination, and cytogenetic studies at 6, 12, 18 and 24 months. RESULTS: Complete hematologic responses were reported for 19 (90.48%) of 21 patients studied. Among 19 patients who had a response, 16 (86%) did so within 3 months. The best cytogenetic response rate at any time during the study treatment with imatinib mesylate, among 14 patients in which cytogenetic response evaluated was: complete cytogenetic response in 7 (50%) patients, partial cytogenetic response in 6 (42.9%) patients and minor cytogenetic response in 1 (7.1%) patient. No patients had progressed to accelerated or blastic phase. The most frequent adverse effects that seemed to be related to treatment with imatinib mesylate were edema and musculoskeletal pain; overall, most were mild. Only one patient discontinued treatment because of hematologic toxic effects. CONCLUSION: The results obtained in this study confirm that imatinib mesylate induces a complete hematological and cytogenetic response in a high percentage of patients with chronic-phase CML. Chronic myelogenous leukemia (CML) is characterized by Philadelphia (Ph) chromosome with a chimeric gene BCR-ABL created by reciprocal t(9:22) (q34;q11) translocation. Variant Ph chromosome translocations involving chromosomes other than 9 and 22 are found in 5-10% of CML cases. We here report a CML patient who carries a four-way Ph chromosome translocation, t(9;22;15;19) (q34;q11;q15;q13). The patient was diagnosed in 1997 and initially treated with hydroxyurea. In 2002, treatment with imatinib, a selective BCR-ABL tyrosine kinase inhibitor (TKI), was started but Ph-positive chromosomes remained at the levels of 42-65%, indicating imatinib failure. In 2006, the point mutations of F359I and L387M were detected in BCR/ABL gene, which may be related to imatinib failure. Treatment with nilotinib, a TKI with high target specificity, was then started which resulted in durable major molecular response. Administration of nilotinib offered an effective treatment in a CML patient with variant Ph chromosome translocations and BCR-ABL point mutations after imatinib failure. Chronic myeloid leukaemia (CML) is a genetically associated maligcy of haematopoietic stem cells, characterized by a t(9;22) translocation that forms the Philadelphia chromosome and creates a novel fusion gene, BCR-ABL. Treatment with molecular-targeted therapy is usually initiated with imatinib, an inhibitor of BCR-ABL tyrosine kinase. Imatinib resistance is, however, observed in some CML patients, especially in those with advanced disease. Through computerized literature searches, a systematic analysis was conducted to examine the efficacy and benefits of dasatinib therapy for imatinib resistant or intolerant CML patients in the chronic phase (CP), accelerated phase (AP) and fatal blast crisis phase (BC). In terms of major haematological and cytogenetic responses, this meta-analysis showed no significant differences in dasatinib treatment between myeloid BC-CML and lymphoid BC-CML patients with imatinib resistance or intolerance. Dasatinib therapy was, however, significantly more effective in improving major haematological and cytogenetic responses for CP-CML patients than for AP-CML patients with imatinib resistance or intolerance. OBJECTIVE: To summarize the use of tyrosine kinase inhibitors (TKIs) for treatment of patients with chronic myeloid leukemia (CML) and provide practical information for patient management. DATA SOURCES: Literature was retrieved from PubMed (2000-January 2011), using the search terms chronic myeloid leukemia and tyrosine kinase inhibitor. Abstracts presented at the 2008-2010 annual meetings of the American Society of Hematology and the American Society of Clinical Oncology, reference citations from identified publications, as well as the manufacturers' full prescribing information for cited drugs, also were reviewed. STUDY SELECTION AND DATA EXTRACTION: Articles evaluating the efficacy and safety of the TKIs imatinib, nilotinib, and dasatinib were evaluated. Focus was placed on publications supporting management of patients with CML in the chronic phase. Reports presenting clinical trial information of TKIs in development also were included. DATA SYNTHESIS: The discovery of targeted tyrosine kinase inhibition of BCR-ABL kinase dramatically changed the treatment of CML. Imatinib, the first TKI approved for treatment of patients with Philadelphia chromosome--positive CML, demonstrated significant superiority over the previous standard of care: interferon plus cytarabine. The newer, more potent TKIs, nilotinib and dasatinib, have demonstrated improved efficacy over imatinib as first-line therapy and provide an effective option for patients with resistance or intolerance to imatinib. CONCLUSIONS: To maximize efficacy of TKI therapy, close patient management, involving frequent monitoring of patient response, is essential. Given the importance of continuing TKI therapy, early recognition and management of adverse events are critical to optimizing outcomes in patients with CML. In addition to the safety profile and considerations of comorbidities, additional factors can affect therapeutic selection, including drug-drug and drug-food interactions. Research investigating new therapies, particularly for patients harboring the T315I mutation-which remains refractory to current TKIs-continues in the quest to improve outcomes in patients with CML. Chronic myelogenous leukemia (CML) accounts for 15-20% of adult leukemias but is very rare in children (2%). Fewer than 10% of CML patients are younger than 20 years. CML is a myeloproliferative disorder characterized by the presence of the Philadelphia chromosome or the BCR-ABL fusion oncogene. The objective of this paper is to present the monitoring of imatinib therapy in two children with CML by the BCR-ABL fusion gene expression assessment from peripheral blood with quantitative real-time polymerase chain reaction (PCR) method. PATIENTS AND METHODS: The 18 and six months follow-up of the patients included clinical examination, routine laboratory tests, bone marrow aspirate investigation including cytogenetic tests and the major BCR-ABL fusion gene expression measurement with qRT-PCR method from the peripheral blood. RESULTS: Patient No. 1 diagnosed with chronic phase CML showed excellent adherence to daily 400 mg imatinib treatment and achieved complete hematologic (CHR) and cytogenetic response (CCR) by three months and major molecular response (MMR) by 12 months, with lack of side effects due to imatinib. Patient No. 2 experienced severe hematologic toxicity, which necessitated temporary withdrawal of the drug. Transient non-compliance together with imatinib dose reduction has driven to treatment failure. In this case, mutational analysis is warranted. CONCLUSIONS: BCR-ABL fusion gene expression level measurement from peripheral blood with qRT-PCR method is an excellent tool in the follow-up of CML patients. PURPOSE: Imatinib induces a durable response in most patients with Philadelphia chromosome-positive chronic myeloid leukemia, but it is currently unclear whether imatinib reduces the leukemic stem cell (LSC) burden, which may be an important step toward enabling safe discontinuation of therapy. In this article, we use mathematical models of BCR-ABL levels to make inferences on the dynamics of LSCs. EXPERIMENTAL DESIGN: Patients with at least 1 BCR-ABL transcript measurement on imatinib were included (N = 477). Maximum likelihood methods were used to test 3 potential hypotheses of the dynamics of BCR-ABL transcripts on imatinib therapy: (i) monoexponential, in which there is little, if any, decline in BCR-ABL transcripts; (ii) biexponential, in which patients have a rapid initial decrease in BCR-ABL transcripts followed by a more gradual response; and (iii) triexponential, in which patients first exhibit a biphasic decline but then have a third phase when BCR-ABL transcripts increase rapidly. RESULTS: We found that most patients treated with imatinib exhibit a biphasic decrease in BCR-ABL transcript levels, with a rapid decrease during the first few months of treatment, followed by a more gradual decrease that often continues over many years. CONCLUSIONS: We show that the only hypothesis consistent with current data on progenitor cell turnover and with the long-term, gradual decrease in the BCR-ABL levels seen in most patients is that these patients exhibit a continual, gradual reduction of the LSCs. This observation may explain the ability to discontinue imatinib therapy without relapse in some cases. Chronic myeloid leukemia (CML) is caused by the BCR-ABL oncogene. The Philadelphia chromosome (Ph) from a reciprocal translocation, t(9;22) (q34;q11) causes a fusion gene, BCR-ABL, that encodes a constitutively active tyrosine kinase. Treatment of CML by imatinib is effective to control the tyrosyl phosphorylation of the protein related to the cell signaling. BCR-ABL mRNA is overexpressed in the minimal residual disease (MRD), known as an early sign of relapse. Between December 2005 and June 2008, we measured BCR-ABL mRNA levels in the bone marrow (BM) from patients by quantitative real-time polymerase chain reaction (RQ-PCR) in Aomori Prefectural Central Hospital. Eighty-six samples from 26 patients were collected. Among the 26 CML patients, 11 patients (42%) were in the pretreatment group. Seven (64%) of the 11 patients achieved complete molecular response (CMR). In the post-treatment group consisting of the remaining 15 patients, 9 (60%) patients achieved CMR. The patients receiving imatinib at a dose over 300 mg per day required 13 (6-77) months [median (range)] to achieve CMR. On the other hand, the patients receiving a dose below 300 mg per day required 29.5 (11-84) months [median (range)]. When BCR-ABL mRNA was detected during the treatment course of patients with CMR, careful observation of BCR-ABL mRNA was useful for tracking the clinical course of patients. In conclusion, the BCR-ABL mRNA level was useful for monitoring the clinical course in 26 patients with CML. Imatinib mesylate (STI 571; Gleevec; Novartis Pharmaceuticals, Basel, Switzerland) is an orally available tyrosine kinase inhibitor that targets a constitutively activated BCR-ABL tyrosine kinase with additional inhibitory effects on platelet derived growth factor (PDGF) receptors alpha and beta, and KIT. It has revolutionized the treatment of adult and pediatric patients with Philadelphia chromosome positive chronic myelogenous leukemia (CML) and is also FDA-approved for KIT-positive advanced gastrointestinal tumor (GIST) and dermatofibrosarcoma protuberans. A wide spectrum of dermatologic toxicities has been associated with this agent, among which a maculopapular rash is the most common event. In addition, a variety of pigmentary abnormalities of the skin and mucosal surfaces have been reported. Hypopigmentation is a well-recognized adverse effect. In contrast, paradoxical hyperpigmentation has only rarely been documented. In this case report we describe imatinib-induced cutaneous hyperpigmentation and graying of hair occurring in the same patient with dermatofibrosarcoma protuberans treated with imatinib. In chronic myeloid leukemia (CML), BCR-ABL-mediated oncogenic signaling can be successfully targeted with the BCRABL- inhibitors imatinib, nilotinib, and dasatinib leading to complete cytogenetic (Philadelphia chromosome not detectable upon cytogenetic testing of bone marrow) and even complete molecular (BCR-ABL not detectable by PCR in peripheral blood) responses. However, CML apparently can not be cured by BCR-ABL inhibitors alone, likely due to treatment-resistance of CML stem/progenitor cells, which provokes a relapse of disease after cessation of therapy. Evidence from patients treated with allogenic stem cell transplantation or IFN-α points to an important role of anti-tumor immunity for durable control of CML disease. Data from multiple in vitro and ex vivo studies indicate that BCR-ABL inhibitors may also influence anti-tumor immunity. Varying effects on different immune effector cell subsets and of the different compounds have been reported, the latter being due to their particular and diverse potency and spectrum of target kinases. As multiple approaches presently aim to combine BCR-ABL inhibition with immunotherapeutic strategies to improve disease control in CML, immunomodulatory effects of the available BCR-ABL inhibitors may be of direct clinical relevance. Here we review the available data regarding the effects of imatinib, nilotinib, and dasatinib on dendritic cells, T cells and natural killer cells as important cellular components of anti-tumor immunity. BACKGROUND: The cytogenetic characteristic of Chronic Myeloid Leukemia (CML) is the formation of the Philadelphia chromosome gene product, BCR-ABL. Given that BCR-ABL is the specific target of Gleevec in CML treatment, we investigated the regulation of the catalytic component of telomerase, hTERT, by BCR-ABL at multiple levels in K562 cells. METHODS: Molecular techniques such as over expression, knockdown, real-time PCR, immunoprecipitation, western blotting, reporter assay, confocal microscopy, telomerase assays and microarray were used to suggest that hTERT expression and activity is modulated by BCR-ABL at multiple levels. RESULTS: Our results suggest that BCR-ABL plays an important role in regulating hTERT in K562 (BCR-ABL positive human leukemia) cells. When Gleevec inhibited the tyrosine kinase activity of BCR-ABL, phosphorylation of hTERT was downregulated, therefore suggesting a positive correlation between BCR-ABL and hTERT. Gleevec treatment inhibited hTERT at mRNA level and significantly reduced telomerase activity (TA) in K562 cells, but not in HL60 or Jurkat cells (BCR-ABL negative cells). We also demonstrated that the transcription factor STAT5a plays a critical role in hTERT gene regulation in K562 cells. Knockdown of STAT5a, but not STAT5b, resulted in a marked downregulation of hTERT mRNA level, TA and hTERT protein level in K562 cells. Furthermore, translocation of hTERT from nucleoli to nucleoplasm was observed in K562 cells induced by Gleevec. CONCLUSIONS: Our data reveal that BCR-ABL can regulate TA at multiple levels, including transcription, post-translational level, and proper localization. Thus, suppression of cell growth and induction of apoptosis by Gleevec treatment may be partially due to TA inhibition. Additionally, we have identified STAT5a as critical mediator of the hTERT gene expression in BCR-ABL positive CML cells, suggesting that targeting STAT5a may be a promising therapeutic strategy for BCR-ABL positive CML patients. Until recently, pediatric Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia (ALL) was associated with an extremely poor outcome when treated with chemotherapy alone, and only modest survival benefits were obtained with the widespread use of hematopoietic stem cell transplantation (HSCT). The development of first-generation (imatinib) and second-generation (dasatinib and nilotinib) tyrosine kinase inhibitors (TKIs) that target the BCR-ABL1 fusion protein produced by the Ph chromosome revolutionized the treatment of chronic myelogenous leukemia (CML). The Children's Oncology Group (COG) AALL0031 trial showed that the addition of imatinib to intensive chemotherapy did not cause increased toxicity and resulted in 3-year event-free survival rates that were more than double those of historical control data from the pre-imatinib era. These findings create a new paradigm for integrating molecularly targeted agents with conventional chemotherapy and call for a reassessment of the routine use of HSCT for children and adolescents with Ph(+) ALL. Second-generation TKIs have theoretical advantages over imatinib, and are now being tested in Ph(+) ALL. The focus of contemporary trials is to define the optimal use of chemotherapy, HSCT, and TKI in Ph(+) ALL. In the coming years, it is anticipated that additional agents will become available to potentiate TKI therapy and/or circumvent TKI resistance in Ph(+) ALL. Recent genomic studies have identified a subtype of high-risk pediatric B-cell-precursor ALL with a gene-expression profile similar to that of Ph(+) ALL, suggestive of active kinase signaling. Many of these Ph-like ALL cases harbor chromosome rearrangements and mutations that dysregulate cytokine receptor and kinase signaling, and these leukemias may also be candidates for TKI therapy. BACKGROUND/AIM: Imatinib mesylate, a selective Bcr-Abl tyrosine kinase inhibitor, has revolutionized the treatment of Bcr-Abl positive chronic myeloid leukemia and become the standard of care for this disease. The aim of this study was evaluation and analysis of cytogenetic response in different intervals and risk groups as well as finding association between pre-treatment characteristics and later probability of achievement of major cytogenetic response. METHODS: We analyzed a total of 22 adult patients with newly diagnosed Philadelphia positive early chronic phase chronic myeloid leukemia treated at our institution from June 2006 to December 2009. RESULTS: The median follow-up time for patients during treatment with imatinib was 25.7 months (range, 12-42 months). A complete hematologic response was achieved in all of the analyzed patients within 6 months from the start of the treatment. The major cytogenetic response rate was 81.8%, and the complete cytogenetic response rate was 72.7%. The patients with low or moderate relative risk had the rate of complementary achieving major and complete cytogenetic response of 75-90%. A multivariate analysis identified the following independent prognostic factors for achieving major cytogenetic response: the absence of splenomegaly, white blood cell count less than 10 x 10(9)/L, the platelet count less than 450 x 10(9)/L, the presence of less than 5% of bone marrow blasts and basophils, the absence of blasts in peripheral blood, the presence of less than 7% of basophils in peripheral blood. CONCLUSION: Patients who early achieve complete and major cytogenetic response as well as those with low and moderate relative risk have a higher rate of achieving and maintaining complete cytogenetic response. There are also characteristics of patients before treatment that may indicate the treatment outcome. PURPOSE: Imatinib is an inhibitor of the Bcr-Abl tyrosine kinase; however, resistance is common. Flavopiridol, a cyclin-dependent kinase (CDK) inhibitor, down-regulates short-lived anti-apoptotic proteins via inhibition of transcription. In preclinical studies, flavopiridol synergizes with imatinib to induce apoptosis. We investigated this novel combination regimen in patients with Bcr-Abl(+) maligcies. METHODS: In a phase I dose-escalation study, imatinib was administered orally daily, and flavopiridol by 1 h intravenous infusion weekly for 3 weeks every 4 weeks. Adults with chronic myelogenous leukemia or Philadelphia chromosome-positive acute leukemia were eligible. Patients were divided into two strata based on peripheral blood and bone marrow blast counts. The primary objective was to identify the recommended phase II doses for the combination. Correlative pharmacokinetic and pharmacodynamic studies were also performed. RESULTS: A total of 21 patients received study treatment. Four dose levels were evaluated before the study was closed following the approval of the second-generation Bcr-Abl tyrosine kinase inhibitors (TKIs). Five patients responded, including four sustained responses. Four patients had stable disease. All but one responder, and all patients with stable disease had previously been treated with imatinib. One patient had a complete response sustained for 30 months. Changes in expression of phospho-Bcr/Abl, -Stat5, and Mcl-1 were monitored. No major pharmacokinetic interaction was observed. CONCLUSIONS: This is the first study to evaluate the combination of a CDK inhibitor and a TKI in humans. The combination of flavopiridol and imatinib is tolerable and produces encouraging responses, including in some patients with imatinib-resistant disease. Imatinib mesylate is the sole BCR-ABL tyrosine kinase inhibitor approved as first-line treatment of accelerated-phase (AP) chronic myeloid leukemia (CML). Indication was based on the STI571 0109 study, in which imatinib favorably compared to historical treatments in patients failing prior therapies. The relevance of these results to currently newly diagnosed AP-CML patients remains unknown. We evaluated the benefit of imatinib in 42 newly diagnosed AP-CML patients. In all, 16 patients had hematological acceleration without chromosomal abnormalities in addition to the Philadelphia chromosome (ACAs; HEM-AP), 16 solely had ACAs (ACA-AP) and 10 had hematological acceleration plus ACAs (HEM-AP + ACA). Major cytogenetic responses were achieved in 93.7% of HEM-AP patients, 75% of patients with ACA-AP (P=NS) and 40% of patients with HEM-AP + ACA (P=0.0053). The 24-month failure-free survival rate was 87.5% in HEM-AP patients, 43.8% in ACA-AP patients and 15% in HEM-AP + ACA patients (P=0.022). The 24-month estimate of progression-free survival was 100% in HEM-AP patients, 92.8% in ACA-AP patients and 58.3% in HEM-AP + ACA patients (P=0.0052). In conclusion, frontline imatinib allows favorable outcomes in HEM-AP and ACA-AP patients but appears insufficient for patients with HEM-AP + ACA. Broader-target and/or more potent BCR-ABL tyrosine kinase inhibitors alone or in combination may be considered in this setting. We conducted a review of patient medical records to assess treatment response patterns and prognostic indicators of response among chronic myeloid leukemia (CML) patients in the United States, the United Kingdom, Germany, and Japan. All 1,063 patients selected met the following inclusion criteria: aged 18 or older and in chronic phase at the time of diagnosis, Philadelphia chromosome and/or BCR-ABL positive, received first-line treatment with imatinib, and not enrolled in a randomized clinical trial during the period of retrospective review. Multivariable logistic regression models were used to evaluate prognostic indicators of complete hematological response (CHR), complete cytogenetic response (CCyR), and complete or major molecular response (C/MMR). Among patients treated with first-line imatinib, CHR at three months, CCyR at 12 months, and C/MMR at 18 months were observed in 53, 53.1, and 57.8 % of patients, respectively. Among patients treated with second-line dasatinib or nilotinib, CHR was achieved at three months in 49 and 42 %, CCyR at 12 months in 32 and 23 %, and MMR at 18 months in 30.5 and 26.1 % of patients, respectively. Prognostic indicators of first-line response included age, race, and Sokal score. For second-line treatment, duration of first-line hematological response and choice of drug used were also significant. Chronic myeloid leukemia (CML) is a pluripotent hematopoietic disorder that is currently considered incurable. The tyrosine kinase product of the Philadelphia chromosome, P210 BCR-ABL, provided a pathogenetic explanation for the initiation of the CML chronic phase and is the molecular therapeutic target for the disease. Imatinib mesylate, an orally available BCR-ABL kinase inhibitor, can induce haematologic and cytogenetic remission of CML. However, imatinib resistance occurs frequently, resulting in relapse. New treatment strategies are focusing on resistant CML stem cells and the bone marrow stroma. The identification of novel pathways and mechanisms in the bone marrow microenvironment could significantly contribute to the development of such strategies. In this work, we used a high-resolution label-free MS(E) proteomic approach to identify differential protein expression in the CML bone marrow plasma of responsive and resistant patients. Oxidative lipid metabolism and regulation of the switch from canonical to noncanonical WNT signaling may contribute to CML resistance in the bone marrow compartment. Imatinib was the first BCR-ABL tyrosine kinase inhibitor to become clinically available. In this study, we retrospectively evaluated the long-term efficacy of low-dose imatinib (final maintece dose <300 mg per day) due to intolerance, in comparison to optimal-dose imatinib (≥300 mg per day) in patients with Philadelphia chromosome-positive chronic myeloid leukemia in the chronic phase. The Kaplan-Meier estimates of the median time to complete cytogenetic response, major molecular response, and complete molecular response were longer for 31 patients receiving low-dose imatinib (360, 1360, and 1420 days, respectively) than 74 patients receiving optimal-dose imatinib (170, 420, and 720 days, respectively). However, the differences in response shrank over time and progression-free survival were comparable between the two groups. These findings suggest that long-term treatment with low-dose imatinib is an acceptable alternative for patients with intolerance to the optimal dose. Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) is triggered by constitutively activated BCR-ABL and SRC family tyrosine kinases.They account for the activations of multiple growth-signaling pathways, including Raf/MEK/ERK, Akt/mTOR and STAT5 pathways. The BCR-ABL tyrosine kinase inhibitor imatinib is the standard treatment for Ph+ leukemia and plays efficacious role in CML. However, imatinib has few inhibitory effects on SRC tyrosine kinase with response rate of Ph+ ALL lower and relapse more frequent and quicker compared with CML. Previous studies showed that oridonin inhibits proliferation and induces apoptosis in many tumor cells. However, the anticancer activity and mechanism of oridonin in Ph+ ALL is unknown. To investigate the anticancer activity of oridonin, we examined its role in constitutively activated Akt/mTOR, Raf/MEK/ERK, STAT5 and SRC pathway, mRNA level of bcr/abl gene, cell viability and apoptosis in Ph+ ALL SUP-B15 cells. Furthermore, we detected synergetic effect of oridonin plus imatinib. Our results showed that oridonin inhibiting activations of LYN (one of SRC family kinases) and ABL and their downstream Akt/mTOR, Raf/MEK/ERK and STAT5 pathways, downregulated Bcl-2 but upregulated Bax protein and then induced apoptosis in Ph+ ALL cells. Oridonin plus imatinib exerted synergetic effects by overcoming imatinib defect of upregulating Akt/mTOR and LYN signaling. Additionally, we examined the effect of oridonin on the signaling pathways in the primary specimens from Ph+ ALL patients. Our data showed that oridonin remarkably suppressed activations of Akt/mTOR, Raf/MEK and STAT5 pathway in these primary specimens and oridonin with imatinib exerted synergetic suppressive effects on mTOR, STAT5 and LYN signaling in one imatinib resistant patient specimen. Additional evaluation of oridonin as a potential therapeutic agent for Ph+ ALL seems warranted. BACKGROUND: Chronic myelogenous leukemia (CML) and Philadelphia chromosome-positive (Ph+) acute lymphatic leukemia (Ph + ALL) are caused by the t(9;22), which fuses BCR to ABL resulting in deregulated ABL-tyrosine kinase activity. The constitutively activated BCR/ABL-kinase "escapes" the auto-inhibition mechanisms of c-ABL, such as allosteric inhibition. The ABL-kinase inhibitors (AKIs) Imatinib, Nilotinib or Dasatinib, which target the ATP-binding site, are effective in Ph + leukemia. Another molecular therapy approach targeting BCR/ABL restores allosteric inhibition. Given the fact that all AKIs fail to inhibit BCR/ABL harboring the 'gatekeeper' mutation T315I, we investigated the effects of AKIs in combination with the allosteric inhibitor GNF2 in Ph + leukemia. METHODS: The efficacy of this approach on the leukemogenic potential of BCR/ABL was studied in Ba/F3 cells, primary murine bone marrow cells, and untransformed Rat-1 fibroblasts expressing BCR/ABL or BCR/ABL-T315I as well as in patient-derived long-term cultures (PDLTC) from Ph + ALL-patients. RESULTS: Here, we show that GNF-2 increased the effects of AKIs on unmutated BCR/ABL. Interestingly, the combination of Dasatinib and GNF-2 overcame resistance of BCR/ABL-T315I in all models used in a synergistic manner. CONCLUSIONS: Our observations establish a new approach for the molecular targeting of BCR/ABL and its resistant mutants using a combination of AKIs and allosteric inhibitors. DISEASE OVERVIEW: Chronic Myeloid Leukemia (CML) is a myeloproliferative neoplasm with an incidence of one-two cases per 100,000 adults and accounts for ∼15% of newly diagnosed cases of leukemia in adults. DIAGNOSIS: CML is characterized by a balanced genetic translocation, t(9;22)(q34;q11.2), involving a fusion of the Abelson oncogene (ABL) from chromosome 9q34 with the breakpoint cluster region (BCR) gene on chromosome 22q11.2. This rearrangement is known as the Philadelphia chromosome. The molecular consequence of this translocation is the generation of a BCR-ABL fusion oncogene, which in turn translates into a Bcr-Abl oncoprotein. FRONTLINE THERAPY: Three tyrosine kinase inhibitors (TKIs), imatinib, nilotinib, and dasatinib, have been approved by the US Food and Drug Administration for the first-line treatment of patients with newly diagnosed CML in chronic phase (CML-CP). Clinical trials with 2nd generation TKIs reported significantly deeper and faster responses; their impact on long-term survival remains to be determined. SALVAGE THERAPY: For patients who fail standard-dose imatinib therapy, imatinib dose escalation is a second-line option. Alternative second-line options include 2nd generation TKIs. Although both are potent and specific BCR-ABL TKIs, dasatinib and nilotinib exhibit unique pharmacological profiles and response patterns relative to different patient characteristics, such as disease stage and BCR-ABL mutational status. Patients who develop the T315I "gatekeeper" mutation display resistance to all currently available TKIs and are candidate for clinical trials. Allogeneic transplantation remains an important therapeutic option for CML-CP harboring the T315I mutation, patients who fail 2nd generation TKIs, and for all patients in advanced phase disease. PECAM-1 (CD31) is an immunoreceptor tyrosine-based inhibitory motif (ITIM)-containing surface glycoprotein expressed on various hematopoietic cells as well as on endothelial cells. PECAM-1 has been shown to play roles in regulation of adhesion, migration and apoptosis. The BCR/ABL fusion tyrosine kinase is expressed in chronic myeloid leukemia and Philadelphia-positive (Ph+) acute lymphoblastic leukemia cells, and its inhibition by the clinically used tyrosine kinase inhibitors imatinib or dasatinib induces apoptosis of these cells. In the present study, we demonstrate that PECAM-1 is tyrosine phospho-rylated in its ITIM motifs in various BCR/ABL-expressing cells including primary leukemia cells. Studies using imatinib and dasatinib as well as transient expression experiments in 293T cells revealed that PECAM-1 was phosphorylated directly by BCR/ABL, which was enhanced by the imatinib-resistant E255K and T315I mutations, or partly by the Src family tyrosine kinases, including Lyn, which were activated dependently or independently on BCR/ABL. We also demonstrate by using a substrate trapping mutant of SHP2 that tyrosine phosphorylated PECAM-1 binds SHP2 and is a major substrate for this tyrosine phosphatase in BCR/ABL-expressing cells. Overexpression of PECAM-1 in BCR/ABL-expressing cells, including K562 human leukemia cells, enhanced cell adhesion and partially inhibited imatinib-induced apoptosis involving mitochondria depolarization and caspase-3 cleavage, at least partly, in an ITIM-independent manner. These data suggest that PECAM-1 may play a role in regulation of apoptosis as well as adhesion of BCR/ABL-expressing cells to modulate their imatinib sensitivity and would be a possible candidate for therapeutic target in Ph+ leukemias. BACKGROUND: The availability of tyrosine kinase inhibitors (TKIs) has considerably changed the management of Philadelphia chromosome positive leukemia. The BCR-ABL inhibitor imatinib is also known to inhibit the tyrosine kinase of the stem cell factor receptor, c-Kit. Nilotinib is 30 times more potent than imatinib towards BCR-ABL in vitro. Studies in healthy volunteers and patients with chronic myelogenous leukemia or gastrointestinal stromal tumors have shown that therapeutic doses of nilotinib deliver drug levels similar to those of imatinib. The aim of this study was to compare the inhibitory effects of imatinib and nilotinib on proliferation, differentiation, adhesion, migration and engraftment capacities of human cord blood CD34(+) cells. DESIGN AND METHODS: After a 48-hour cell culture with or without TKIs, CFC, LTC-IC, migration, adhesion and cell cycle analysis were performed. In a second time, the impact of these TKIs on engraftment was assessed in a xenotransplantation model using NOD/SCID/IL-2Rγ (null) mice. RESULTS: TKIs did not affect LTC-IC frequencies despite in vitro inhibition of CFC formation due to inhibition of CD34(+) cell cycle entry. Adhesion of CD34(+) cells to retronectin was reduced in the presence of either imatinib or nilotinib but only at high concentrations. Migration through a SDF-1α gradient was not changed by cell culture in the presence of TKIs. Finally, bone marrow cellularity and human chimerism were not affected by daily doses of imatinib and nilotinib in a xenogenic transplantation model. No significant difference was seen between TKIs given the equivalent affinity of imatinib and nilotinib for KIT. CONCLUSIONS: These data suggest that combining non-myeloablative conditioning regimen with TKIs starting the day of the transplantation could be safe. The reciprocal translocation between chromosomes 9 and 22 [t(9;22)(q34;q11), Philadelphia chromosome] creates a BCR-ABL1 fusion protein that occurs in approximately 95% of cases of chronic myelogenous leukemia (CML), 15% of cases of adult acute lymphoblastic leukemia, and 5% of adult cases of acute myeloid leukemia. The BCR-ABL1 protein is a constitutively activated tyrosine kinase that induces and maintains the neoplastic phenotype in these leukemias. PCR-based methods to identify and quantitate the tumor-specific BCR-ABL1 RNA have been shown to be an ultrasensitive diagnostic, prognostic, and monitoring tool for Philadelphia-positive leukemias. A novel tyrosine kinase inhibitor (TKI), imatinib, has been confirmed as an effective targeted treatment in most CML patients. However, a significant minority of patients being treated with imatinib develop resistance to the drug as evidenced by rising BCR-ABL1 levels. The most common mechanism of resistance in these patients is the development of mutations in the BCR-ABL1 kinase domain (KD) that abrogate binding of imatinib. Although KD mutations are quite heterogeneous, the identification of the exact mutation site is clinically important, as some mutations, but not others, can be effectively treated with second-generation TKIs. One mutation, T315I, for example, renders the leukemia resistant to all first- and second-line TKIs. Thus, DNA sequencing of the BCR-ABL1 kinase domain in resistant patients helps identify those who may benefit from a change in TKI agents, or those who should be considered for other therapeutic measures, such as stem cell transplantation. We describe here a method for sequencing the BCR-ABL1 kinase domain in peripheral blood or bone marrow of CML patients. PURPOSE: Dasatinib is a dual Abl/Src tyrosine kinase inhibitor (TKI) designed as a prototypic short-acting BCR-ABL-targeted TKI that inhibits BCR-ABL with greater potency compared with imatinib, nilotinib, bosutinib, and ponatinib and has been shown to have potential immunomodulatory effects. Dasatinib is approved for the treatment of all phases of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia resistant or intolerant to prior imatinib treatment and first-line treatment for CML in chronic phase. In this article, the development of dasatinib as a treatment for patients with CML is reviewed. METHODS: This is a review of the relevant literature regarding dasatinib development in CML (2003-2013). RESULTS: Dasatinib demonstrates efficacy against most BCR-ABL mutations arising during imatinib therapy and is effective in treating patients with imatinib resistance due to other mechanisms. Randomized trial data show that first-line dasatinib provides superior responses compared with imatinib and enables patients to achieve early, deep responses correlated with improved longer-term outcomes. Dasatinib has a generally acceptable safety profile, with most adverse events (AEs) proving manageable and reversible. Cytopenias are commonly observed with dasatinib, and some nonhematologic AEs including pleural effusion have been consistently reported. CONCLUSION: Dasatinib is an effective treatment option for patients with CML.

When was empagliflozin FDA approved?

Empagliflozin was approved in 2014 by the European Commission and the United States Food and Drug Administration for the treatment of type 2 diabetes mellitus (T2DM).

OBJECTIVE: To review available studies of empagliflozin, a sodium glucose co-transporter-2 (SGLT2) inhibitor approved in 2014 by the European Commission and the United States Food and Drug Administration for the treatment of type 2 diabetes mellitus (T2DM). DATA SOURCES: PubMed was searched using the search terms empagliflozin, BI 10773, and BI10773, for entries between January 1, 2000, and December 1, 2014. Reference lists from retrieved articles were searched manually for additional peer-reviewed publications. STUDY SELECTION AND DATA EXTRACTION: All publications reporting clinical trials of empagliflozin were eligible for inclusion. DATA SYNTHESIS: Empagliflozin is a new once-daily oral SGLT2 inhibitor with a mechanism of action that is independent of β-cell function and the insulin pathway. Data from a comprehensive phase III clinical trial program have demonstrated its efficacy as monotherapy, as add-on to other glucose-lowering agents, and in different patient populations. In these studies, empagliflozin resulted in improvements in blood glucose levels as well as reductions in body weight and blood pressure. Empagliflozin was well tolerated and was not associated with an increased risk of hypoglycemia versus placebo. CONCLUSION: The oral antidiabetes agent, empagliflozin, can be used as monotherapy or alongside other glucose-lowering treatments, including insulin, to treat T2DM.

Which R/bioconductor package is used for integrative genomics visualizations?

Sushi.R is a flexible, quantitative and integrative genomic visualizations for publication-quality multi-panel figures using common genomic data formats including Browser Extensible Data (BED), bedGraph and Browser Extensible Data Paired-End (BEDPE). Sushi.R is open source and made publicly available through GitHub (https://github.com/dphansti/Sushi) and Bioconductor (http://bioconductor.org/packages/release/bioc/html/Sushi.html).

List symptoms of congenital toxoplasmosis triad.

Classic triad of toxoplasmosis include hydrocephalus, cerebral calcification and chorioretinitis.

Toxoplasma gondii was discovered by scientists working in North Africa and Brazil around 100 years ago. The parasite has since been found to be capable of infecting all warm-blooded animals including humans making it one of the most successful parasitic organisms worldwide. The pathogenic potential of T. gondii was recognized in the 1920s and 1930s, in congenitally infected children presenting with the classic triad of symptoms, namely hydrocephalus, retinochoroiditis and encephalitis. In addition, around the same time T. gondii parasites were found to be associated with severe intraocular inflammation. In the 1980s, T. gondii emerged as a major cause of death in patients with acquired immunodeficiency syndrome, illustrating the importance of the immune system in controlling T. gondii infection. T. gondii was reported as a major cause of abortion in sheep in New Zealand in the 1950s, which raised questions about potential new transmission routes for the parasite. The discovery of the cat as the definitive host in the 1960s was a very important finding as it helped to complete our understanding of the parasite's life cycle, and the oocyst stage of T. gondii shed in the faeces of infected cats was found to be an important source of infection for many intermediate hosts and helped to explain infection in herbivorous animals and people with a vegetarian diet. In addition, this stage of the parasite was very robust and could survive in the environment, depending on the climatic conditions, for up to 12-18 months. Knowledge of the parasite's life cycle, transmission routes, risk groups and host immune responses has helped in the development of strategies to control the disease, reduce transmission of the parasite and limit environmental contamination.

How many genes are imprinted in the human genome?

Among approximately 70 known imprinted genes are some causing disorders affecting growth, metabolism and cancer predisposition.

DNA methylation is a covalent modification of the nucleotide cytosine that is stably inherited at the dinucleotide CpG by somatic cells, and 70% of CpG dinucleotides in the genome are methylated. The exception to this pattern of methylation are CpG islands, CpG-rich sequences that are protected from methylation, and generally are thought to be methylated only on the inactive X-chromosome and in tumors, as well as differentially methylated regions (DMRs) in the vicinity of imprinted genes. To identify chromosomal regions that might harbor imprinted genes, we devised a strategy for isolating a library of normally methylated CpG islands. Most of the methylated CpG islands represented high copy number dispersed repeats. However, 62 unique clones in the library were characterized, all of which were methylated and GC-rich, with a GC content >50%. Of these, 43 clones also showed a CpG(obs)/CpG(exp) >0.6, of which 30 were studied in detail. These unique methylated CpG islands mapped to 23 chromosomal regions, and 12 were differentially methylated regions in uniparental tissues of germline origin, i.e., hydatidiform moles (paternal origin) and complete ovarian teratomas (maternal origin), even though many apparently were methylated in somatic tissues. We term these sequences gDMRs, for germline differentially methylated regions. At least two gDMRs mapped near imprinted genes, HYMA1 and a novel homolog of Elongin A and Elongin A2, which we term Elongin A3. Surprisingly, 18 of the methylated CpG islands were methylated in germline tissues of both parental origins, representing a previously uncharacterized class of normally methylated CpG islands in the genome, and which we term similarly methylated regions (SMRs). These SMRs, in contrast to the gDMRs, were significantly associated with telomeric band locations (P =.0008), suggesting a potential role for SMRs in chromosome organization. At least 10 of the methylated CpG islands were on average 85% conserved between mouse and human. These sequences will provide a valuable resource in the search for novel imprinted genes, for defining the molecular substrates of the normal methylome, and for identifying novel targets for mammalian chromatin formation. Genomic imprinting is a mechanism by which only one copy of a gene pair is expressed, and this expression is determined by the parental origin of the copy. The deregulation of imprinted genes has been implicated in a number of human diseases. The Imprinted Gene Catalogue now has more than 200 genes listed, and estimates based on mouse models suggest many more may exist in humans. Therefore, the development of methods to identify such genes is important. In this communication, we present a parametric model-based approach to analyzing arbitrary-sized pedigree data for genomic imprinting. We have modified widely used LINKAGE program to incorporate our proposed approach. In addition, our approach allows for the use of sex-specific recombinations in the analysis, which is of particular importance in a genome-wide analysis for imprinted genes. We compared our imprinting analysis approach to that implemented in the GENEHUNTER-IMPRINT program using simulation studies as well as by analyzing causal genes in Angelman's syndrome families, which are known to be imprinted. These analyses showed that the proposed approach is very powerful for detecting imprinted genes in large pedigrees. Genomic imprinting is an epigenetic mechanism that results in monoallelic expression of genes depending on parent-of-origin of the allele. Although the conservation of genomic imprinting among mammalian species has been widely reported for many genes, there is accumulating evidence that some genes escape this conservation. Most known imprinted genes have been identified in the mouse and human, with few imprinted genes reported in cattle. Comparative analysis of genomic imprinting across mammalian species would provide a powerful tool for elucidating the mechanisms regulating the unique expression of imprinted genes. In this study we analyzed the imprinting of 22 genes in human, mouse, and cattle and found that in only 11 was imprinting conserved across the three species. In addition, we analyzed the occurrence of the sequence elements CpG islands, C + G content, tandem repeats, and retrotransposable elements in imprinted and in nonimprinted (control) cattle genes. We found that imprinted genes have a higher G + C content and more CpG islands and tandem repeats. Short interspersed nuclear elements (SINEs) were notably fewer in number in imprinted cattle genes compared to control genes, which is in agreement with previous reports for human and mouse imprinted regions. Long interspersed nuclear elements (LINEs) and long terminal repeats (LTRs) were found to be significantly underrepresented in imprinted genes compared to control genes, contrary to reports on human and mouse. Of considerable significance was the finding of highly conserved tandem repeats in nine of the genes imprinted in all three species. Genomic imprinting characterizes genes with a monoallelic expression, which is dependent on the parental origin of each allele. Approximately 150 imprinted genes are known to date, in humans and mice but, though computational searches have tried to extract intrinsic characteristics of these genes to identify new ones, the existing list is probably far from being comprehensive. We used a high-throughput strategy by diverting the classical use of genotyping microarrays to compare the genotypes of mRNA/cDNA vs. genomic DNA to identify new genes presenting monoallelic expression, starting from human placental material. After filtering of data, we obtained a list of 1,082 putative candidate monoallelic SNPs located in more than one hundred candidate genes. Among these, we found known imprinted genes, such as IPW, GRB10, INPP5F and ZNF597, which contribute to validate the approach. We also explored some likely candidates of our list and identified seven new imprinted genes, including ZFAT, ZFAT-AS1, GLIS3, NTM, MAGI2, ZC3H12Cand LIN28B, four of which encode zinc finger transcription factors. They are, however, not imprinted in the mouse placenta, except for Magi2. We analyzed in more details the ZFAT gene, which is paternally expressed in the placenta (as ZFAT-AS1, a non-coding antisense RNA) but biallelic in other tissues. The ZFAT protein is expressed in endothelial cells, as well as in syncytiotrophoblasts. The expression of this gene is, moreover, downregulated in placentas from complicated pregcies. With this work we increase by about 10% the number of known imprinted genes in humans. BACKGROUND: Dysregulation of imprinted genes, which are expressed in a parent-of-origin-specific manner, plays an important role in various human diseases, such as cancer and behavioral disorder. To date, however, fewer than 100 imprinted genes have been identified in the human genome. The recent availability of high-throughput technology makes it possible to have large-scale prediction of imprinted genes. Here we propose a Bayesian model (dsPIG) to predict imprinted genes on the basis of allelic expression observed in mRNA-Seq data of independent human tissues. RESULTS: Our model (dsPIG) was capable of identifying imprinted genes with high sensitivity and specificity and a low false discovery rate when the number of sequenced tissue samples was fairly large, according to simulations. By applying dsPIG to the mRNA-Seq data, we predicted 94 imprinted genes in 20 cerebellum samples and 57 imprinted genes in 9 diverse tissue samples with expected low false discovery rates. We also assessed dsPIG using previously validated imprinted and non-imprinted genes. With simulations, we further analyzed how imbalanced allelic expression of non-imprinted genes or different minor allele frequencies affected the predictions of dsPIG. Interestingly, we found that, among biallelically expressed genes, at least 18 genes expressed significantly more transcripts from one allele than the other among different individuals and tissues. CONCLUSION: With the prevalence of the mRNA-Seq technology, dsPIG has become a useful tool for analysis of allelic expression and large-scale prediction of imprinted genes. For ease of use, we have set up a web service and also provided an R package for dsPIG at http://www.shoudanliang.com/dsPIG/.

Is exome sequencing efficient for the detection of germline mutations?

Exome sequencing is an efficient, sensitive, rapid and relatively cheap method for detection of germline mutations.

The advent of next-generation sequencing technologies has revolutionized the study of genetic variation in the human genome. Whole-genome sequencing currently represents the most comprehensive strategy for variant detection genome-wide but is costly for large sample sizes, and variants detected in noncoding regions remain largely uninterpretable. By contrast, whole-exome sequencing has been widely applied in the identification of germline mutations underlying Mendelian disorders, somatic mutations in various cancers and de novo mutations in neurodevelopmental disorders. Since whole-exome sequencing focuses upon the entire set of exons in the genome (the exome), it requires additional exome-enrichment steps compared with whole-genome sequencing. Although the availability of multiple commercial exome-enrichment kits has made whole-exome sequencing technically feasible, it has also added to the overall cost. This has led to the emergence of transcriptome (or RNA) sequencing as a potential alternative approach to variant detection within protein coding regions, since the transcriptome of a given tissue represents a quasi-complete set of transcribed genes (mRNAs) and other noncoding RNAs. A further advantage of this approach is that it bypasses the need for exome enrichment. Here we discuss the relative merits and limitations of these approaches as they are applied in the context of variant detection within gene coding regions. Melanoma of the eye is a rare and distinct subtype of melanoma, which only rarely are familial. However, cases of uveal melanoma (UM) have been found in families with mixed cancer syndromes. Here, we describe a comprehensive search for inherited genetic variation in a family with multiple cases of UM but no aggregation of other cancer diagnoses. The proband is a woman diagnosed with UM at 16 years who within 6 months developed liver metastases. We also identified two older paternal relatives of the proband who had died from UM. We performed exome sequencing of germline DNA from members of the affected family. Exome-wide analysis identified a novel loss-of-function mutation in the BAP1 gene, previously suggested as a tumor suppressor. The mutation segregated with the UM phenotype in this family, and we detected a loss of the wild-type allele in the UM tumor of the proband, strongly supporting a causative association with UM. Screening of BAP1 germline mutations in families predisposed for UM may be used to identify individuals at increased risk of disease. Such individuals may then be enrolled in preventive programs and regular screenings to facilitate early detection and thereby improve prognosis.

Which cellular processes are regulated by Nanog?

The pluripotency sustaining factor Nanog, controls a cascade of pathways that are intricately connected to govern pluripotency, self-renewal, genome surveillance and cell fate determination. Elevated expression of Nanog has also been reported to result in clonal expansion of murine ESCs, but it also plays a role in tumor development. A positive regulator of cell proliferation, it is essential for G1 to S transition in human embryonic stem cells while it regulates primordial germ cell migration.

Nanog is a newly identified homeodomain gene that functions to sustain the pluripotency of embryonic stem cells. However, the molecular mechanism through which og regulates stem cell pluripotency remains unknown. Mouse og encodes a polypeptide of 305 residues with a divergent homeodomain similar to those in the NK-2 family. The rest of og contains no apparent homology to any known proteins characterized so far. It is hypothesized that og encodes a transcription factor that regulates stem cell pluripotency by switching on or off target genes. To test this hypothesis, we constructed fusion proteins between og and DNA binding domains of the yeast transcription factor Gal4 and tested the transactivation potentials of these constructs. Our data demonstrate that both regions N- and C- terminal to the homeodomain have transcription activities. Despite the fact that it contains no apparent transactivation motifs, the C-terminal domain is about 7 times as active as the N-terminal one. This unique arrangement of dual transactivators may confer og the flexibility and specificity to regulate downstream genes critical for both pluripotency and differentiation of stem cells. Oct4 and Nanog are transcription factors required to maintain the pluripotency and self-renewal of embryonic stem (ES) cells. Using the chromatin immunoprecipitation paired-end ditags method, we mapped the binding sites of these factors in the mouse ES cell genome. We identified 1,083 and 3,006 high-confidence binding sites for Oct4 and Nanog, respectively. Comparative location analyses indicated that Oct4 and Nanog overlap substantially in their targets, and they are bound to genes in different configurations. Using de novo motif discovery algorithms, we defined the cis-acting elements mediating their respective binding to genomic sites. By integrating RNA interference-mediated depletion of Oct4 and Nanog with microarray expression profiling, we demonstrated that these factors can activate or suppress transcription. We further showed that common core downstream targets are important to keep ES cells from differentiating. The emerging picture is one in which Oct4 and Nanog control a cascade of pathways that are intricately connected to govern pluripotency, self-renewal, genome surveillance and cell fate determination. In this study, we show that NANOG, a master transcription factor, regulates S-phase entry in human embryonic stem cells (hESCs) via transcriptional regulation of cell cycle regulatory components. Chromatin immunoprecipitation combined with reporter-based transfection assays show that the C-terminal region of NANOG binds to the regulatory regions of CDK6 and CDC25A genes under normal physiological conditions. Decreased CDK6 and CDC25A expression in hESCs suggest that both CDK6 and CDC25A are involved in S-phase regulation. The effects of NANOG overexpression on S-phase regulation are mitigated by the down-regulation of CDK6 or CDC25A alone. Overexpression of CDK6 or CDC25A alone can rescue the impact of NANOG down-regulation on S-phase entry, suggesting that CDK6 and CDC25A are downstream cell cycle effectors of NANOG during the G1 to S transition. Tumor development has long been known to resemble abnormal embryogenesis. The embryonic stem cell (ESC) self-renewal gene NANOG is purportedly expressed by some epithelial cancer cells but a causal role in tumor development has remained unclear. Here, we provide compelling evidence that cultured cancer cells, as well as xenograft- and human primary prostate cancer cells express a functional variant of NANOG. NANOG mRNA in cancer cells is derived predomitly from a retrogene locus termed NANOGP8. NANOG protein is detectable in the nucleus of cancer cells and is expressed higher in patient prostate tumors than matched benign tissues. NANOGP8 mRNA and/or NANOG protein levels are enriched in putative cancer stem/progenitor cell populations. Importantly, extensive loss-of-function analysis reveals that RNA interference-mediated NANOG knockdown inhibits tumor development, establishing a functional significance for NANOG expression in cancer cells. Nanog short hairpin RNA transduced cancer cells exhibit decreased long-term clonal and clonogenic growth, reduced proliferation and, in some cases, altered differentiation. Thus, our results demonstrate that NANOG, a cell-fate regulatory molecule known to be important for ESC self-renewal, also plays a novel role in tumor development. Nanog is involved in controlling pluripotency and differentiation of stem cells in vitro. However, its function in vivo has been studied only in mouse embryos and various reports suggest that Nanog may not be required for the regulation of differentiation. To better understand endogenous Nanog function, more animal models should be introduced to complement the murine model. Here, we have identified the homolog of the mammalian Nanog gene in teleost fish and describe the endogenous expression of Ol-Nanog mRNA and protein during medaka (Oryzias latipes) embryonic development and in the adult gonads. Using medaka fish as a vertebrate model to study Nanog function, we demonstrate that Ol-Nanog is necessary for S-phase transition and proliferation in the developing embryo. Moreover, inhibition or overexpression of Ol-Nanog does not affect gene expression of various pluripotency and differentiation markers, suggesting that this transcription factor may not play a direct role in embryonic germ layer differentiation. STEM CELLS 2009;27:2081-2091. A cohort of genes associated with embryonic stem (ES) cell behaviour, including NANOG, are expressed in a number of human cancers. They form an ES-like signature we first described in glioblastoma multiforme (GBM), a highly invasive and incurable brain tumour. We have also shown that HEDGEHOG-GLI (HH-GLI) signalling is required for GBM growth, stem cell expansion and the expression of this (ES)-like stemness signature. Here, we address the function of NANOG in human GBMs and its relationship with HH-GLI activity. We find that NANOG modulates gliomasphere clonogenicity, CD133(+) stem cell cell behavior and proliferation, and is regulated by HH-GLI signalling. However, GLI1 also requires NANOG activity forming a positive loop, which is negatively controlled by p53 and vice versa. NANOG is essential for GBM tumourigenicity in orthotopic xenografts and it is epistatic to HH-GLI activity. Our data establish NANOG as a novel HH-GLI mediator essential for GBMs. We propose that this function is conserved and that tumour growth and stem cell behaviour rely on the status of a functional GLI1-NANOG-p53 network. Mouse embryonic stem cells (ESCs) require transcriptional regulation to ensure rapid proliferation that allows for self-renewal. However, the molecular mechanism by which transcriptional factors regulate this rapid proliferation remains largely unknown. Here we present data showing that CIBZ, a BTB domain zinc finger transcriptional factor, is a key transcriptional regulator for regulation of ESC proliferation. Here we show that deletion or siRNA knockdown of CIBZ inhibits ESC proliferation. Cell cycle analysis shows that loss of CIBZ delays the progression of ESCs through the G1 to S phase transition. Conversely, constitutive ectopic expression of exogenous CIBZ in ESCs promotes proliferation and accelerates G1/S transition. These findings suggest that regulation of the G1/S transition explains, in part, CIBZ-associated ESC proliferation. Our data suggest that CIBZ acts through the post-transcriptionally regulates the expression of Nanog, a positive regulator of ESC proliferation and G1/S transition, but does not affect Oct3/4 and Sox2 protein expression. Notably, constitutive overexpression of Nanog partially rescued the proliferation defect caused by CIBZ knockdown, indicating the role of CIBZ in ESC proliferation and G1/S transition at least in part depends on the Nanog protein level. In mammalian embryonic stem cells, the acquisition of pluripotency is dependent on Nanog, but the in vivo analysis of Nanog has been hampered by its requirement for early mouse development. In an effort to examine the role of Nanog in vivo, we identified a zebrafish Nanog ortholog and found that its knockdown impaired endoderm formation. Genome-wide transcription analysis revealed that og-like morphants fail to develop the extraembryonic yolk syncytial layer (YSL), which produces Nodal, required for endoderm induction. We examined the genes that were regulated by Nanog-like and identified the homeobox gene mxtx2, which is both necessary and sufficient for YSL induction. Chromatin immunoprecipitation assays and genetic studies indicated that Nanog-like directly activates mxtx2, which, in turn, specifies the YSL lineage by directly activating YSL genes. Our study identifies a Nanog-like-Mxtx2-Nodal pathway and establishes a role for Nanog-like in regulating the formation of the extraembryonic tissue required for endoderm induction. Nanog and FAK were shown to be overexpressed in cancer cells. In this report, the Nanog overexpression increased FAK expression in 293, SW480, and SW620 cancer cells. Nanog binds the FAK promoter and up-regulates its activity, whereas Nanog siRNA decreases FAK promoter activity and FAK mRNA. The FAK promoter contains four Nanog-binding sites. The site-directed mutagenesis of these sites significantly decreased up-regulation of FAK promoter activity by Nanog. EMSA showed the specific binding of Nanog to each of the four sites, and binding was confirmed by ChIP assay. Nanog directly binds the FAK protein by pulldown and immunoprecipitation assays, and proteins co-localize by confocal microscopy. Nanog binds the N-terminal domain of FAK. In addition, FAK directly phosphorylates Nanog in a dose-dependent manner by in vitro kinase assay and in cancer cells in vivo. The site-directed mutagenesis of Nanog tyrosines, Y35F and Y174F, blocked phosphorylation and binding by FAK. Moreover, overexpression of wild type Nanog increased filopodia/lamellipodia formation, whereas mutant Y35F and Y174F Nanog did not. The wild type Nanog increased cell invasion that was inhibited by the FAK inhibitor and increased by FAK more significantly than with the mutants Y35F and Y174F Nanog. Down-regulation of Nanog with siRNA decreased cell growth reversed by FAK overexpression. Thus, these data demonstrate the regulation of the FAK promoter by Nanog, the direct binding of the proteins, the phosphorylation of Nanog by FAK, and the effect of FAK and Nanog cross-regulation on cancer cell morphology, invasion, and growth that plays a significant role in carcinogenesis.

In which cells are A-type lamins expressed?

In the rat brain, lamin A and C are expressed in relatively equal amounts, while the expressions of lamin B1 and B2 vary depending on the cell type. Human cells with reduced expression of the major B-type lamin protein, lamin B1, were generated using RNA interference. In addition, horizontal cells and a subpopulation of retinal ganglion cells expressed lamin A and C, while photoreceptor cells expressed neither lamin A nor C, and all other retinal neurons expressed lamin C only. Parallel in vivo experiments showed that treatment with thioglycollate caused the percentage of lamin A/C-positive peritoneal macrophages to increase from 5 to 80% between Days 0 and 6.

The peripheral lamina of eukaryotic nuclei is composed of polypeptides called lamins that vary in number from one to four according to organism, cell type, and differentiated state of the cells. Early embryonic cells and stem cells of mammals generally possess only lamin B while lamins A and C appear later during differentiation. To study the role of the late appearance of lamins A and C in the differentiated phenotype, we have performed transfection of cDNAs coding for human lamins A or C into mouse embryonal carcinoma (EC) cell lines F9 and P19 lacking these two lamins. Transient transfections have shown that lamins A or C could be expressed, translocated to the peripheral lamina, and distributed into daughter cell nuclei after mitosis. These results demonstrated that EC cells devoid of lamins A and C nevertheless possessed the appropriate mechanisms for the localization and mitotic redistribution of exogenous lamins A and C. The nuclear lamina consists of a proteinaceous layer or meshwork situated subjacent to the inner nuclear membrane. It is a karyoskeletal structure formed by a polymer containing one to three major polypeptides collectively termed the lamins. In all cells examined of vertebrates and invertebrates, the lamins exhibit very similar Mr ranging from 60 000 to 80 000. In vertebrates, two groups of lamins can be distinguished by their isoelectric value, one being near-neutral and the other acidic (isoelectric pH values of 5.6 and lower). The lamins represent a family of polypeptides with regions highly conserved during evolution. In certain species, e.g., the amphibian, Xenopus laevis, they exhibit cell type-specific expression during embryonic development, terminal differentiation of certain somatic cells, and gametogenesis. The nuclear lamina of diverse cell types can be composed of one, two or three different lamin polypeptides, without obvious differences in its morphology. Mouse A-type lamin genes were isolated. Structural analyses revealed that all the three known mouse A-type lamins (A, C and C2) were coded in a single genomic locus in a 22 kilobase DNA segment. The three lamins were coded in 12, 10 and 10 exons for A, C and C2, respectively, and shared 8 exons among them. Primer extension analyses identified possible transcription start sites for both A/C and C2 genes suggesting that the locus is under the control of two separate promoters, that is a somatic cell-acting promoter (for A and C) and a testis-specific promoter (for C2) which resides in the first intron of the A/C gene. Sequence characteristics of the possible promoter regions are discussed. Divergence of the two somatic cell-type lamins (A and C) is formally accounted for by differential selection of poly(A) sites together with lamin A-specific splicing. AIMS: In order to clarify the differentiation and proliferation status of the Reed-Sternberg and Hodgkin cells we studied A and B-type lamin expression with specific monoclonal antibodies in nodular sclerosing Hodgkin's disease. Its normal counterpart, the reactive lymph node, was also examined for lamin subtype expression. METHODS AND RESULTS: The CD20 positive centrocytes and centroblasts of the follicle centre in the reactive lymph nodes expressed lamin B1, but were not or only very weakly positive for lamin B2 or A-type lamin antibodies. Mantle zone lymphocytes displayed lamins B1 and B2, but were negative for A-type lamins. Furthermore, CD3- and CD20-positive lymphocytes in the medulla and paracortex lacked A-type lamins, but were positive for both B-type lamins. Finally, the proliferation marker Ki67 was mainly detected in the centroblasts, but also in a fraction of the A-type lamin negative cells in the paracortex and medulla. In Hodgkin's disease, all cells expressed lamins B1 and B2, whereas A-type lamins were primarily observed in CD30-positive Reed-Sternberg and Hodgkin cells. About 20% of the Reed-Sternberg and Hodgkin cells expressed Ki67, with co-expression of lamin A in most of these cells. CONCLUSIONS: Ki67 and A-type lamin staining were in general mutually exclusive in lymph nodes, indicating that A-type lamin positive cells are not proliferative. This suggests also that the A-type lamin expression in Reed-Sternberg and Hodgkin cells is correlated with a relatively mature phenotype of these maligt cells. However, some of these differentiated maligt cells still have a capacity to proliferate as indicated by Ki67 positivity. Our observation that lamin B2 expression in the follicle centre cells of the reactive lymph node is low or absent indicates that this lamin subtype is not always expressed in nucleated cells, which is in clear contrast to the results obtained in previous studies in other diseases and in normal tissues. Absence of lamin B2 expression may be associated with the follicle centre stage of B-cells. We have examined the expression of lamins A, B1, and C in human tissues and cancer cell lines and the function of the lamin A/C and B1 gene promoters in transfected cells. Northern analysis and immunoblotting demonstrated that lamin A/C mRNA and protein were not detectable in some human cell lines whereas lamin B1 was always present. Sequencing of approximately 2.6 kb of the lamin A/C and 1.6 kb of the lamin B1 genes 5' to the translation initiation sites showed that they did not contain typical TATA boxes near the transcription start sites. The lamin B1 and A/C proximal promoter regions were transcribed in transfected HeLa, Raji, and NT2/D1 cell lines even if the cells did not contain detectable endogenous lamin A/C mRNA or protein. These results show that, similar to most cytoplasmic intermediate filament genes, transcriptional regulatory elements in the promoters of the human nuclear lamin A/C and B1 genes do not control their cell type-specific expression in culture lines. Nuclear lamins comprise the nuclear lamina, a scaffold-like structure that lines the inner nuclear membrane. B-type lamins are present in almost all cell types, but A-type lamins are expressed predomitly in differentiated cells, suggesting a role in maintece of the differentiated state. Previous studies have shown that lamin A/C is not expressed during mouse development before day 9, nor in undifferentiated mouse embryonic carcinoma cells. To further investigate the role of lamins in cell phenotype maintece and differentiation, we examined lamin expression in undifferentiated mouse and human embryonic stem (ES) cells. Wide-field and confocal immunofluorescence microscopy and semiquantitative reverse transcription-polymerase chain reaction analysis revealed that undifferentiated mouse and human ES cells express lamins B1 and B2 but not lamin A/C. Mouse ES cells display high levels of lamins B1 and B2 localized both at the nuclear periphery and throughout the nucleoplasm, but in human ES cells, B1 and B2 expression is dimmer and localized primarily at the nuclear periphery. Lamin A/C expression is activated during human ES cell differentiation before downregulation of the pluripotency marker Oct-3/4 but not before the downregulation of the pluripotency markers Tra-1-60, Tra-1-81, and SSEA-4. Our results identify the absence of A-type lamin expression as a novel marker for undifferentiated ES cells and further support a role for nuclear lamins in cell maintece and differentiation. Gametogenesis and embryogenesis are dynamic developmental stages marked by extensive modifications in the organization of the genome and nuclear architecture. In the literature it is conveyed that only B-type lamins are required in these early stages of development and that A-type lamins are not present or required until differentiation of specific cell types associated with specialized tissue is initiated. To assess the presence of nuclear structures that are putatively involved in genome regulation, we investigated the distribution of lamin proteins throughout the early stages of porcine embryonic development, using testes tissue sections, oocytes and in-vitro fertilized (IVF) porcine embryos and employing anti-lamin antibodies. We have shown that anti-lamin A staining is present at the one-cell, two-cell, four-cell, and six- to eight-cell stages of early porcine embryo development, but diminishes at the morulae and blastocyst stages. Large intranuclear anti-lamin A foci are prominent in the early preimplantation stages. Both anti-lamin A/C and anti-lamin B staining were clearly present in all embryonic stages. Immature porcine oocytes revealed lamin rings using the monoclonal anti-lamin A/C antibody and many immature oocytes exhibited a pale rim staining pattern with anti-lamin A antibody. A-type lamins were not observed in sperm precursor cells. Thus, we have shown that A-type lamins and B-type lamins are present at the nuclear envelope in very early porcine embryos and that lamin A is also found in large intranuclear aggregates in two-cell to eight-cell embryos but is lacking from later embryonic stages. Lamins are type V intermediate filament proteins that support nuclear membranes. They are divided into A-type lamins, which include lamin A and C, and B-type lamins, which include lamin B1 and B2. In the rat brain, lamin A and C are expressed in relatively equal amounts, while the expressions of lamin B1 and B2 vary depending on the cell type. Lamins play important roles in normal morphogenesis and function. In the nervous system, their abnormal expression causes several neurodegenerative diseases such as peripheral neuropathy, leukodystrophy and lissencephaly. The retina belongs to the central nervous system (CNS) and has widely been used as a source of CNS neurons. We investigated the expression patterns of lamin subtypes in the adult rat retina by immunohistochemistry and found that the staining patterns differed when compared with the brain. All retinal neurons expressed lamin B1 and B2 in relatively equal amounts. In addition, horizontal cells and a subpopulation of retinal ganglion cells expressed lamin A and C, while photoreceptor cells expressed neither lamin A nor C, and all other retinal neurons expressed lamin C only. This differential expression pattern of lamins in retinal neurons suggests that they may be involved in cellular differentiation and expression of cell-specific genes in individual retinal neurons.

What is the definition of autophagy?

There are several definitions of autophagy. Among them, autophagy can be defined as a non- apoptotic programmed cell death that consists on a catabolic trafficking pathway for bulk destruction and turnover of long-lived proteins and organelles via regulated lysosomal degradation.

Apoptosis is a physiological method of cell death commonly referred to as programmed cell death. However, non-apoptotic programmed cell death, such as autophagy and programmed necrosis, has been characterized by morphological criteria. In view of the human therapeutic use of DEX, and considering that no difference in the number and/or affinity of glucocorticoid receptors in activated and non-activated lymphocytes has been reported, we decided to evaluate the effect of DEX on fresh peripheral blood mononuclear cells (PBMC). Transmission electron microscopy showed that DEX can significantly induce apoptosis in non-activated PBMC. It was also observed by transmission electron microscopy that, independently of DEX treatment, PBMC also died by a process marked by extreme vacuolization and increase in cellular volume; these cells were erroneously classified as viable by flow cytometry using the 7-AAD assay. It is concluded that the DEX pro-apoptotic effect is not restricted to activated PBMC and, therefore, DEX-induced apoptosis could play either homeostatic (activated PBMC) or immunosuppressive (non-activated PBMC) roles. Autophagy is a catabolic trafficking pathway for bulk destruction and turnover of long-lived proteins and organelles via regulated lysosomal degradation. In eukaryotic cells, autophagy occurs constitutively at low levels to perform housekeeping functions, such as the destruction of dysfunctional organelles. Up-regulation occurs in the presence of external stressors (e.g. starvation, hormonal imbalance and oxidative stress) and internal needs (e.g. removal of protein aggregates), suggesting that the process is an important survival mechanism. However, the occurrence of autophagic structures in dying cells of different organisms has led to the hypothesis that autophagy may also have a causative role in stress-induced cell death. The identification within the last decade of a full set of genes essential for autophagy in yeast, the discovery of human orthologues and the definition of signalling pathways regulating autophagy have accelerated our molecular understanding and interest in this fundamental process. A growing body of evidence indicates that autophagy is associated with heart disease, cancer and a number of neurodegenerative disorders, such as Alzheimer's, Parkinson's and Huntington's diseases. Furthermore, it has been demonstrated that autophagy plays a role in embryogenesis, aging and immunity. Recently, it has been shown that autophagy can be intensified by specific drugs. The pharmacological modulation of the autophagic pathway represents a major challenge for clinicians to treat human disease. Autophagy is a ubiquitous eukaryotic cytoplasmic quality and quantity control pathway. The role of autophagy in cytoplasmic homeostasis seamlessly extends to cell-autonomous defense against intracellular microbes. Recent studies also point to fully integrated, multitiered regulatory and effector connections between autophagy and nearly all facets of innate and adaptive immunity. Autophagy in the immune system as a whole confers measured immune responses; on the flip side, suppression of autophagy can lead to inflammation and tissue damage, as evidenced by Crohn's disease predisposition polymorphisms in autophagy basal apparatus (Atg16L) and regulatory (IRGM) genes. Polymorphisms in the IRGM gene in human populations have also been linked to predisposition to tuberculosis. There are several areas of most recent growth: first, links between autophagy regulators and infectious disease predisposition in human populations; second, demonstration of a role for autophagy in infection control in vivo in animal models; third, the definition of specific antiautophagic defenses in highly evolved pathogens; and fourth, recognition of connections between the ubiquitin system and autophagy of bacteria (and interestingly mitochondria, which are incidentally organelles of bacterial evolutionary origin) via a growing list of modifier and adapter proteins including p62/SQSTM1, NDP52, Atg32, Parkin, and Nix/BNIP3L. Autophagy has been predomitly studied as a nonselective self-digestion process that recycles macromolecules and produces energy in response to starvation. However, autophagy independent of nutrient status has long been known to exist. Recent evidence suggests that this form of autophagy enforces intracellular quality control by selectively disposing of aberrant protein aggregates and damaged organelles--common denominators in various forms of neurodegenerative diseases. By definition, this form of autophagy, termed quality-control (QC) autophagy, must be different from nutrient-regulated autophagy in substrate selectivity, regulation and function. We have recently identified the ubiquitin-binding deacetylase, HDAC6, as a key component that establishes QC. HDAC6 is not required for autophagy activation per se; rather, it is recruited to ubiquitinated autophagic substrates where it stimulates autophagosome-lysosome fusion by promoting F-actin remodeling in a cortactin-dependent manner. Remarkably, HDAC6 and cortactin are dispensable for starvation-induced autophagy. These findings reveal that autophagosomes associated with QC are molecularly and biochemically distinct from those associated with starvation autophagy, thereby providing a new molecular framework to understand the emerging complexity of autophagy and therapeutic potential of this unique machinery. Autophagy is the endogenous, tightly regulated cellular "housekeeping" process responsible for the degradation of damaged and dysfunctional cellular organelles and protein aggregates. There is a growing consensus that autophagy is upregulated in the setting of myocardial ischemia-reperfusion. Moreover, emerging data suggest that autophagy may serve as an adaptive process and confer increased resistance to ischemia-reperfusion injury. Our aims in this review are to (1) provide a brief synopsis of process of autophagy (including an overview of the key molecular mediators of this catabolic process and its relationship with other cardiac signaling pathways) and (2) most importantly, summarize the current evidence for versus against the intriguing concept of autophagy-mediated cardioprotection. Relatively little is known about programmed cell death (PCD) in plants. It is nonetheless suggested here that tonoplast rupture and the subsequent rapid destruction of the cytoplasm can distinguish two large PCD classes. One class, which is here called 'autolytic', shows this feature, whilst the second class (called 'non-autolytic') can include tonoplast rupture but does not show the rapid cytoplasm clearance. Examples of the 'autolytic' PCD class mainly occur during normal plant development and after mild abiotic stress. The 'non-autolytic' PCD class is mainly found during PCD that is due to plant-pathogen interactions. Three categories of PCD are currently recognized in animals: apoptosis, autophagy, and necrosis. An attempt is made to reconcile the recognized plant PCD classes with these groups. Apoptosis is apparently absent in plants. Autophagic PCD in animals is defined as being accompanied by an increase in the number of autophagosomes, autolysosomes, and small lytic vacuoles produced by autolysosomes. When very strictly adhering to this definition, there is no (proof for) autophagic PCD in plants. Upon a slightly more lenient definition, however, the 'autolytic' class of plant PCD can be merged with the autophagic PCD type in animal cells. The 'non-autolytic' class of plant PCD, as defined here, can be merged with necrotic PCD in animals. The current working definition of autophagy is the following: all processes in which intracellular material is degraded within the lysosome/vacuole and where the macromolecular constituents are recycled. There are several ways to classify the different types of autophagy. For example, we can separate autophagy into two primary types, based on the initial site of cargo sequestration. In particular, during microautophagy and chaperone-mediated autophagy, uptake occurs directly at the limiting membrane of the lysosome or vacuole. In contrast, macroautophagy-whether selective or nonselective-and endosomal microautophagy involve sequestration within an autophagosome or an omegasome, or late endosomes/multivesicular bodies, respectively; the key point being that in these types of autophagy the initial sequestration event does not occur at the limiting membrane of the degradative organelle. In any case, the cargo is ultimately delivered into the lysosome or vacuole lumen for subsequent degradation. Thus, I think most autophagy researchers view the degradative organelle as the ultimate destination of the pathway. Indeed, this fits with the general concept that organelles allow reactions to be compartmentalized. With regard to the lysosome or vacuole, this also confers a level of safety by keeping the lytic contents away from the remainder of the cell. If we are willing to slightly modify our definition of autophagy, with a focus on "degradation of a cell's own components through the lysosomal/vacuolar machinery," we can include a newly documented process, programmed nuclear destruction (PND). Autophagy and senescence share a number of characteristics, which suggests that both responses could serve to collaterally protect the cell from the toxicity of external stress such as radiation and chemotherapy and internal forms of stress such as telomere shortening and oncogene activation. Studies of oncogene activation in normal fibroblasts as well as exposure of tumor cells to chemotherapy have indicated that autophagy and senescence are closely related but not necessarily interdependent responses; specifically, interference with autophagy delays but does not abrogate senescence. The literature relating to this topic is inconclusive, with some reports appearing to be consistent with a direct relationship between autophagy and senescence and others indicative of an inverse relationship. Before this question can be resolved, additional studies will be necessary where autophagy is clearly inhibited by genetic silencing and where the temporal responses of both autophagy and senescence are monitored, preferably in cells that are intrinsically incapable of apoptosis or where apoptosis is suppressed. Understanding the nature of this relationship may provide needed insights relating to cytoprotective as well as potential cytotoxic functions of both autophagy and senescence. With regard to cell biology, one area of focus that has shifted back and forth over the years has been the relative emphasis on catabolic versus anabolic processes: the breakdown of glucose, the synthesis of DNA, the oxidation of pyruvate, the biogenesis of membranes, protein degradation, and protein synthesis. Historically, the majority of studies concerned with degradation dealt with the production of energy; however, the analysis of the ubiquitin-proteasome system revealed the importance of protein degradation for controlling various aspects of cell physiology. The ubiquitin-proteasome system is limited primarily to targeting individual proteins for destruction, but cells also have to deal with larger structures that are damaged, potentially toxic or superfluous, and these substrates, including entire organelles, are the purview of autophagy. As a general definition, autophagy encompasses a range of processes in which the cell degrades parts of itself within the lysosome (or the analogous organelle, the vacuole, in yeast and plants), followed by the release and reuse of the breakdown products. Thus, autophagy is in part a mechanism for cellular recycling, but such a definition belies the importance of the different autophagic processes in cell and organismal function and homeostasis. Indeed, defects in autophagy are associated with many human diseases and metabolic disorders. Here, we provide a brief overview of the mechanism of autophagy and some of the physiological roles in which this process is involved. Not surprisingly, the death of a cell is a complex and well controlled process. For several decades, apoptosis, the first genetically programmed death process to be identified has taken centre stage as the principal mechanism of programmed cell death (type I cell death) in mammalian tissues. Apoptosis has been extensively studied and its contribution to the pathogenesis of disease well documented. However, apoptosis does not function alone in determining the fate of a cell. More recently, autophagy, a process in which de novo formed membrane enclosed vesicles engulf and consume cellular components, has been shown to engage in complex interplay with apoptosis. As a result, cell death has been subdivided into the categories apoptosis (Type I), autophagic cell death (Type II), and necrosis (Type III). The boundary between Type I and II cell death is not completely clear and as we will discuss in this review and perhaps a discrete difference does not exist, due to intrinsic factors among different cell types and crosstalk among organelles within each cell type. Apoptosis may begin with autophagy and autophagy can often end with apoptosis, inhibition or a blockade of caspase activity may lead a cell to default into Type II cell death from Type I.

Gene silencing can be achieved by RNA interference (RNAi) in eukaryotic organisms. What is the name of the analogous process in prokaryotic organisms?

Bacteria have developed several defense mechanisms against bacteriophages over evolutionary time, but the concept of prokaryotic RNA interference mediated defense mechanism against phages and other invading genetic elements has emerged only recently. Clustered regularly interspaced short palindromic repeats (CRISPR) together with closely associated genes (cas genes) constitute the CASS system that is believed to provide a RNAi-like defense mechanism against bacteriophages within the host bacterium.

BACKGROUND: All archaeal and many bacterial genomes contain Clustered Regularly Interspaced Short Palindrome Repeats (CRISPR) and variable arrays of the CRISPR-associated (cas) genes that have been previously implicated in a novel form of DNA repair on the basis of comparative analysis of their protein product sequences. However, the proximity of CRISPR and cas genes strongly suggests that they have related functions which is hard to reconcile with the repair hypothesis. RESULTS: The protein sequences of the numerous cas gene products were classified into approximately 25 distinct protein families; several new functional and structural predictions are described. Comparative-genomic analysis of CRISPR and cas genes leads to the hypothesis that the CRISPR-Cas system (CASS) is a mechanism of defense against invading phages and plasmids that functions analogously to the eukaryotic RNA interference (RNAi) systems. Specific functional analogies are drawn between several components of CASS and proteins involved in eukaryotic RNAi, including the double-stranded RNA-specific helicase-nuclease (dicer), the endonuclease cleaving target mRNAs (slicer), and the RNA-dependent RNA polymerase. However, none of the CASS components is orthologous to its apparent eukaryotic functional counterpart. It is proposed that unique inserts of CRISPR, some of which are homologous to fragments of bacteriophage and plasmid genes, function as prokaryotic siRNAs (psiRNA), by base-pairing with the target mRNAs and promoting their degradation or translation shutdown. Specific hypothetical schemes are developed for the functioning of the predicted prokaryotic siRNA system and for the formation of new CRISPR units with unique inserts encoding psiRNA conferring immunity to the respective newly encountered phages or plasmids. The unique inserts in CRISPR show virtually no similarity even between closely related bacterial strains which suggests their rapid turnover, on evolutionary scale. Corollaries of this finding are that, even among closely related prokaryotes, the most commonly encountered phages and plasmids are different and/or that the domit phages and plasmids turn over rapidly. CONCLUSION: We proposed previously that Cas proteins comprise a novel DNA repair system. The association of the cas genes with CRISPR and, especially, the presence, in CRISPR units, of unique inserts homologous to phage and plasmid genes make us abandon this hypothesis. It appears most likely that CASS is a prokaryotic system of defense against phages and plasmids that functions via the RNAi mechanism. The functioning of this system seems to involve integration of fragments of foreign genes into archaeal and bacterial chromosomes yielding heritable immunity to the respective agents. However, it appears that this inheritance is extremely unstable on the evolutionary scale such that the repertoires of unique psiRNAs are completely replaced even in closely related prokaryotes, presumably, in response to rapidly changing repertoires of domit phages and plasmids. BACKGROUND: In eukaryotes, RNA interference (RNAi) is a major mechanism of defense against viruses and transposable elements as well of regulating translation of endogenous mRNAs. The RNAi systems recognize the target RNA molecules via small guide RNAs that are completely or partially complementary to a region of the target. Key components of the RNAi systems are proteins of the Argonaute-PIWI family some of which function as slicers, the nucleases that cleave the target RNA that is base-paired to a guide RNA. Numerous prokaryotes possess the CRISPR-associated system (CASS) of defense against phages and plasmids that is, in part, mechanistically analogous but not homologous to eukaryotic RNAi systems. Many prokaryotes also encode homologs of Argonaute-PIWI proteins but their functions remain unknown. RESULTS: We present a detailed analysis of Argonaute-PIWI protein sequences and the genomic neighborhoods of the respective genes in prokaryotes. Whereas eukaryotic Ago/PIWI proteins always contain PAZ (oligonucleotide binding) and PIWI (active or inactivated nuclease) domains, the prokaryotic Argonaute homologs (pAgos) fall into two major groups in which the PAZ domain is either present or absent. The monophyly of each group is supported by a phylogenetic analysis of the conserved PIWI-domains. Almost all pAgos that lack a PAZ domain appear to be inactivated, and the respective genes are associated with a variety of predicted nucleases in putative operons. An additional, uncharacterized domain that is fused to various nucleases appears to be a unique signature of operons encoding the short (lacking PAZ) pAgo form. By contrast, almost all PAZ-domain containing pAgos are predicted to be active nucleases. Some proteins of this group (e.g., that from Aquifex aeolicus) have been experimentally shown to possess nuclease activity, and are not typically associated with genes for other (putative) nucleases. Given these observations, the apparent extensive horizontal transfer of pAgo genes, and their common, statistically significant over-representation in genomic neighborhoods enriched in genes encoding proteins involved in the defense against phages and/or plasmids, we hypothesize that pAgos are key components of a novel class of defense systems. The PAZ-domain containing pAgos are predicted to directly destroy virus or plasmid nucleic acids via their nuclease activity, whereas the apparently inactivated, PAZ-lacking pAgos could be structural subunits of protein complexes that contain, as active moieties, the putative nucleases that we predict to be co-expressed with these pAgos. All these nucleases are predicted to be DNA endonucleases, so it seems most probable that the putative novel phage/plasmid-defense system targets phage DNA rather than mRNAs. Given that in eukaryotic RNAi systems, the PAZ domain binds a guide RNA and positions it on the complementary region of the target, we further speculate that pAgos function on a similar principle (the guide being either DNA or RNA), and that the uncharacterized domain found in putative operons with the short forms of pAgos is a functional substitute for the PAZ domain. CONCLUSION: The hypothesis that pAgos are key components of a novel prokaryotic immune system that employs guide RNA or DNA molecules to degrade nucleic acids of invading mobile elements implies a functional analogy with the prokaryotic CASS and a direct evolutionary connection with eukaryotic RNAi. The predictions of the hypothesis including both the activities of pAgos and those of the associated endonucleases are readily amenable to experimental tests. Compelling evidence indicates that the CRISPR-Cas system protects prokaryotes from viruses and other potential genome invaders. This adaptive prokaryotic immune system arises from the clustered regularly interspaced short palindromic repeats (CRISPRs) found in prokaryotic genomes, which harbor short invader-derived sequences, and the CRISPR-associated (Cas) protein-coding genes. Here, we have identified a CRISPR-Cas effector complex that is comprised of small invader-targeting RNAs from the CRISPR loci (termed prokaryotic silencing (psi)RNAs) and the RAMP module (or Cmr) Cas proteins. The psiRNA-Cmr protein complexes cleave complementary target RNAs at a fixed distance from the 3' end of the integral psiRNAs. In Pyrococcus furiosus, psiRNAs occur in two size forms that share a common 5' sequence tag but have distinct 3' ends that direct cleavage of a given target RNA at two distinct sites. Our results indicate that prokaryotes possess a unique RNA silencing system that functions by homology-dependent cleavage of invader RNAs. Bacteria have developed several defense mechanisms against bacteriophages over evolutionary time, but the concept of prokaryotic RNA interference mediated defense mechanism against phages and other invading genetic elements has emerged only recently. Clustered regularly interspaced short palindromic repeats (CRISPR) together with closely associated genes (cas genes) constitute the CASS system that is believed to provide a RNAi-like defense mechanism against bacteriophages within the host bacterium. However, a CASS mediated RNAi-like pathway in enteric pathogens such as Vibrio cholerae O395 or Escherichia coli O157 have not been reported yet. This study specifically was designed to investigate the possibility and evolutionary origin of CASS mediated RNAi-like pathway in the genome of a set of enteric pathogens, especially V. cholerae. The results showed that V. cholerae O395 and also other related enteric pathogens have the essential CASS components (CRISPR and cas genes) to mediate a RNAi-like pathway. The functional domains of a V. cholerae Cas3 protein, which is believed to act as a prokaryotic Dicer, was revealed and compared with the domains of eukaryotic Dicer proteins. Extensive homology in several functional domains provides significant evidence that the Cas3 protein has the essential domains to play a vital role in RNAi like pathway in V. cholerae. The secondary structure of the pre-siRNA for V. cholerae O395 was determined and its thermodynamic stability also reinforced the previous findings and signifies the probability of a RNAi-like pathway in V. cholerae O395. The CRISPR/Cas system in prokaryotes provides resistance against invading viruses and plasmids. Three distinct stages in the mechanism can be recognized. Initially, fragments of invader DNA are integrated as new spacers into the repetitive CRISPR locus. Subsequently, the CRISPR is transcribed and the transcript is cleaved by a Cas protein within the repeats, generating short RNAs (crRNAs) that contain the spacer sequence. Finally, crRNAs guide the Cas protein machinery to a complementary invader target, either DNA or RNA, resulting in inhibition of virus or plasmid proliferation. In this article, we discuss our current understanding of this fascinating adaptive and heritable defense system, and describe functional similarities and differences with RNAi in eukaryotes.

Between which types of DNA bases are mutational biases introduced due to directional mutation pressure?

The rates of substitution mutations in two directions, v (from an AT-pair to a GC-pair) and u (from a GC-pair to an AT-pair), are usually not the same. Thereafter, the effect of mutation on a genome is not random but has a directionality toward higher or lower GC content of DNA. The net effect, v/(u + v), has previously been defined as directional mutation pressure. Thus, directional mutation pressure (GC/AT pressure) refers to mutational biases between alpha-bases (A or T) and gamma-bases (G or C).

The genetic code has been influenced by directional mutation pressure affecting the base composition of DNA, sometimes in the direction of increased GC content and at other times, in the direction of AT. Such pressure led to changes in species-specific usages of codons and tRNA anticodons, and also in amino acid assignments of codons in mitochondria and in several intact organisms. These code changes are probably recent evolutionary events. The genetic code is not 'frozen', but instead it is still evolving. The prokaryotic genetic code has been influenced by directional mutation pressure (GC/AT pressure) that has been exerted on the entire genome. This pressure affects the synonymous codon choice, the amino acid composition of proteins and tRNA anticodons. Unassigned codons would have been produced in bacteria with extremely high GC or AT genomes by deleting certain codons and the corresponding tRNAs. A high AT pressure together with genomic economization led to a change in assignment of the UGA codon, from stop to tryptophan, in Mycoplasma. A quantitative theory of directional mutation pressure proposed in 1962 explained the wide variation of DNA base composition observed among different bacteria and its small heterogeneity within individual bacterial species. The theory was based on the assumption that the effect of mutation on a genome is not random but has a directionality toward higher or lower guanine-plus-cytosine content of DNA, and this pressure generates directional changes more in neutral parts of the genome than in functionally significant parts. Now that DNA sequence data are available, the theory allows the estimation of the extent of neutrality of directional mutation pressure against selection. Newly defined parameters were used in the analysis, and two apparently universal constants were discovered. Analysis of DNA sequence has revealed that practically all organisms are subject to directional mutation pressure. The theory also offers plausible explanations for the large heterogeneity in guanine-plus-cytosine content among different parts of the vertebrate genome. Clues to evolution of the genetic code can be found by comparing usage of anticodons in various organisms and organelles. GC content of DNA varies, as a result of directional mutation pressure (AT/GC pressure), especially in bacteria. Low GC in Mycoplasma is accompanied by use of UGA for tryptophan and, in ciliated protozoa, by use of UAA and UAG for glutamine. These are examples of "stop codon capture," which has been preceded by duplication of tRNA genes followed by nucleotide substitutions in their sequences, including mutational changes in their anticodons. Evolutionary changes in the code may have resulted from disappearance of codons and anticodons resulting from GC pressure and from their reappearance when the direction of the pressure was reversed. In this manner, codon UGA and anticodon UCA for tryptophan could have disappeared under GC pressure and reappeared in Mycoplasma under AT pressure. Stop codon UGA may have been the third of the three stop codons to appear, originating from mutations in UAA. Changes in the code are adaptive and nondeleterious. We propose that the number of anticodons has increased and that evolution continued until three existing forms of the universal code were produced: eukaryotic, eubacterial, and the code for halobacteria and methanococci. These three codes are distinguished from each other by their anticodon pattern. The eukaryotic code contains eight INN (ANN) anticodons that have replaced GNN anticodons as a result of AT pressure. Mitochondrial and chloroplast codes have evolved from the eubacterial code through genomic economization and AT pressure, leading to losses of GNN and CNN anticodons.(ABSTRACT TRUNCATED AT 250 WORDS) We present a new approach for analyzing directional mutation pressure and nucleotide content in protein-coding genes. Directional mutation pressure, the heterogenicity in the likelihood of different nucleotide substitutions, is used to explain the increasing or decreasing guanine-cytosine content (GC%) in DNA and is represented by microD, in agreement with Sueoka (1962, Proc Natl Acad Sci USA 48:582-592). The new method uses simulation to facilitate identification of significant A+T or G+C pressure as well as the comparison of directional mutation pressure among genes, even when they are translated by different genetic codes. We use the method to analyze the evolution of directional mutation pressure and nucleotide content of mitochondrial cytochrome b genes. Results from a survey of 110 taxa indicate that the cytochrome b genes of most taxa are subjected to significant directional mutation pressure and that the gene is subject to A+T pressure in most cases. Only in the anseriform bird Cairina moschata is the cytochrome b gene subject to significant G+C pressure. The GC% at nonsynonymous codon sites decreases proportionately with increasing A+T pressure, and with a slope less than one, indicating a presence of selective constraints. The cytochrome b genes of insects, nematodes, and eumycotes are subject to extreme A+T pressures (microD = 0.123, 0.224, and 0.130) and, in parallel, the GC% of the nonsynonymous codon sites has decreased from about 0.44 in organisms that are not subjected to A+T or G+C pressure to about 0.332, 0.323, and 0.367, respectively. The distribution of taxa according to the GC% at nonsynonymous codon sites and directional mutation pressure supports the notion that variation in these parameters is a phylogenetic component. Using a general form of the directional mutation theory, this paper analyzes the effect of mutations in mutator genes on the G+C content of DNA, the frequency of substitution mutations, and evolutionary changes (cumulative mutations) under various degrees of selective constraints. Directional mutation theory predicts that when the mutational bias between A/T and G/C nucleotide pairs is equilibrated with the base composition of a neutral set of DNA nucleotides, the mutation frequency per gene will be much lower than the frequency immediately after the mutator mutation takes place. This prediction explains the wide variation of the DNA G+C content among unicellular organisms and possibly also the wide intragenomic heterogeneity of third codon positions for the genes of multicellular eukaryotes. The present analyses lead to several predictions that are not consistent with a number of the frequently held assumptions in the field of molecular evolution, including belief in a constant rate of evolution, symmetric branching of phylogenetic trees, the generality of higher mutation frequency for neutral sets of nucleotides, the notion that mutator mutations are generally deleterious because of their high mutation rates, and teleological explanations of DNA base composition. As a result of the nucleotide sequence analysis of an aphid endosymbiont's operon homologous to the Escherichia coli groE, we noted that directional base substitutions tending toward an increase of A + T content represent an obvious evolutionary trend in this prokaryotic operon, housed for a long period by an eukaryotic cell. This result, when taken together with previous reports, raised the possibility that genomic DNA of prokaryotes residing in an eukaryotic cell is subject to A/T-biased directional mutation pressure and/or both negative and positive selection operating under conditions specific to the intracellular environments.

Is it feasible to determine the complete proteome of yeast?

Yes, since the complete genome of yeast is known.

N-Myristoylation is an irreversible modification that affects the membrane binding properties of crucial cytoplasmic proteins from signal transduction cascades. We characterized the two putative N-myristoyltransferases of Arabidopsis thaliana as a means of investigating the entire N-myristoylation proteome (N-myristoylome) in a higher eukaryote. AtNMT1 compensated for the nmt1 defect in yeast, whereas AtNMT2 and chimeras of the two genes did not. Only AtNMT1 modified known N-myristoylated proteins in vitro. AtNMT1 is therefore responsible for the A. thaliana N-myristoylome, whereas AtNMT2 does not seem to have usual myristoylation activity. We began with the whole set of N-myristoylated G proteins in the A. thaliana proteome. We then used a reiterative approach, based on the in vitro N-myristoylation of more than 60 different polypeptides, to determine the substrate specificity of AtNMT1. We found that the positive charge on residue 7 of the substrate was particularly important in substrate recognition. The A. thaliana N-myristoylome consists of 437 proteins, accounting for 1.7% of the complete proteome. We demonstrated the N-myristoylation of several unexpected protein families, including innate immunity proteins, thioredoxins, components of the protein degradation pathway, transcription factors, and a crucial regulatory enzyme of glycolysis. The role of N-myristoylation is discussed in each case; in particular, this process may underlie the "guard" hypothesis of innate immunity. Isotope labelling of proteins is important for progress in the field of structural proteomics. It enables the utilisation of the power of nuclear magnetic resoce spectroscopy (NMR) for the characterisation of the three-dimensional structures and corresponding dynamical features of proteins. The usual approach to obtain isotopically labelled protein molecules is by expressing the corresponding gene in bacterial or yeast host organisms, which grow on isotope-enriched media. This method has several drawbacks. Here, we demonstrate that it is possible to fully label a plant with (15)N-isotopes. The advantage of in vivo labelling of higher organisms is that all constituting proteins are labelled and become available as functional, post-translationally modified, correctly folded proteins. A hydroponics set-up was used to create the first example of a uniformly (15)N-labelled (> 98%) plant species, the potato plant (Solanum tuberosum L., cv. Elkana). Two plants were grown at low costs using potassium-[(15)N]-nitrate as the sole nitrogen source. At harvest time, a total of 3.6 kg of potato tubers and 1.6 kg of foliage, stolons and roots were collected, all of which were fully (15)N-labelled. Gram quantities of soluble (15)N-labelled proteins (composed mainly of the glycoprotein patatin and Kunitz-type protease inhibitors) were isolated from the tubers. NMR results on the complete proteome of potato sap and on an isolated protease inhibitor illustrate the success of the labelling procedure. The presented method of isotope labelling is easily modified to label other plants. Its envisioned impact in the field of structural proteomics of plants is discussed. Although mass spectrometry has become a powerful tool for the functional analysis of biological systems, complete proteome characterization cannot yet be achieved. Instead, the sheer complexity of living organisms demands fractionation of cellular extracts to enable more targeted analyses. Here, we introduce the concept of "fluorous proteomics," whereby specific peptide subsets from samples of biological origin are tagged with perfluorinated moieties and subsequently enriched by solid-phase extraction over a fluorous-functionalized stationary phase. This approach is extremely selective, yet can readily be tailored to enrich different subsets of peptides. Additionally, this methodology overcomes many of the limitations of traditional bioaffinity-based enrichment strategies, while enabling new affinity enrichment schemes impossible to implement with bioaffinity reagents. The potential of this methodology is demonstrated by the facile enrichment of peptides bearing particular side-chain functionalities or post-translational modifications from tryptic digests of individual proteins as well as whole cell lysates. BACKGROUND: Mass spectrometry has become a powerful tool for the analysis of large numbers of proteins in complex samples, enabling much of proteomics. Due to various analytical challenges, so far no proteome has been sequenced completely. O'Shea, Weissman and co-workers have recently determined the copy number of yeast proteins, making this proteome an excellent model system to study factors affecting coverage. RESULTS: To probe the yeast proteome in depth and determine factors currently preventing complete analysis, we grew yeast cells, extracted proteins and separated them by one-dimensional gel electrophoresis. Peptides resulting from trypsin digestion were analyzed by liquid chromatography mass spectrometry on a linear ion trap-Fourier transform mass spectrometer with very high mass accuracy and sequencing speed. We achieved unambiguous identification of more than 2,000 proteins, including very low abundant ones. Effective dynamic range was limited to about 1,000 and effective sensitivity to about 500 femtomoles, far from the subfemtomole sensitivity possible with single proteins. We used SILAC (stable isotope labeling by amino acids in cell culture) to generate one-to-one pairs of true peptide signals and investigated if sensitivity, sequencing speed or dynamic range were limiting the analysis. CONCLUSION: Advanced mass spectrometry methods can unambiguously identify more than 2,000 proteins in a single proteome. Complex mixture analysis is not limited by sensitivity but by a combination of dynamic range (high abundance peptides preventing sequencing of low abundance ones) and by effective sequencing speed. Substantially increased coverage of the yeast proteome appears feasible with further development in software and instrumentation. Experience from different fields of life sciences suggests that accessible, complete reference maps of the components of the system under study are highly beneficial research tools. Examples of such maps include libraries of the spectroscopic properties of molecules, or databases of drug structures in analytical or forensic chemistry. Such maps, and methods to navigate them, constitute reliable assays to probe any sample for the presence and amount of molecules contained in the map. So far, attempts to generate such maps for any proteome have failed to reach complete proteome coverage. Here we use a strategy based on high-throughput peptide synthesis and mass spectrometry to generate an almost complete reference map (97% of the genome-predicted proteins) of the Saccharomyces cerevisiae proteome. We generated two versions of this mass-spectrometric map, one supporting discovery-driven (shotgun) and the other supporting hypothesis-driven (targeted) proteomic measurements. Together, the two versions of the map constitute a complete set of proteomic assays to support most studies performed with contemporary proteomic technologies. To show the utility of the maps, we applied them to a protein quantitative trait locus (QTL) analysis, which requires precise measurement of the same set of peptides over a large number of samples. Protein measurements over 78 S. cerevisiae strains revealed a complex relationship between independent genetic loci, influencing the levels of related proteins. Our results suggest that selective pressure favours the acquisition of sets of polymorphisms that adapt protein levels but also maintain the stoichiometry of functionally related pathway members.

Which mutations of alpha-myosin heavy chain gene are implicated in hypertrophic cardiomyopathy?

The following mutations of alpha-myosin heavy chain gene are implicated in hypertrophic cardiomyopathy: R403Q; Q1065H and Arg-249-->Gln

To analyze potential functional consequences of myosin heavy chain (MHC) mutations identified in patients with familial hypertrophic cardiomyopathy (FHC), we have assessed the stability of the mutant MHCs and their ability to form thick filaments. Constructs encoding wild-type rat alpha MHC and seven corresponding FHC missense mutants were transfected into COS cells. Immunoblot analysis suggested that FHC mutations do not grossly alter protein stability. Wild-type alpha MHC transfected into COS cells forms structures previously shown to be arrays of thick filaments, which also resemble myosin structures observed early in differentiation of muscle cells. Surprisingly, up to 29% of COS cells transfected with the FHC mutants failed to form filamentous structures. To assess whether this phenotype was specific for the FHC mutants and not generalizable to any myosin mutation, COS cells were transfected with a construct encoding an MHC with a 168-amino acid deletion of the hinge/rod region. This deletion construct formed filamentous structures with the same frequency as wild-type MHC. Biochemical analysis of one FHC mutant (Arg-249-->Gln) demonstrates that the structures formed by the mutant are solubilized at a lower ionic strength than those formed by wild-type MHC. We conclude that although the FHC mutant MHC is not labile, its assembly properties may be impaired. A new mouse cardiac electrophysiology method was used to study mice harboring an alpha-myosin heavy chain Arg403Gln missense mutation (alpha-MHC403/+), which results in histological and hemodynamic abnormalities characteristic of familial hypertrophic cardiomyopathy (FHC) and sudden death of uncertain etiology during exercise. Wild-type animals had completely normal cardiac electrophysiology. In contrast, FHC mice demonstrated (a) electrocardiographic abnormalities including prolonged repolarization intervals and rightward axis; (b) electrophysiological abnormalities including heterogeneous ventricular conduction properties and prolonged sinus node recovery time; and (c) inducible ventricular ectopy. These data identify distinct electrophysiologic abnormalities in FHC mice with a specific alpha-myosin mutation, and also validate a novel method to explore in vivo the relationship between specific genotypes and their electrophysiologic phenotypes. Genetically-manipulated mice harboring an alpha-myosin heavy chain Arg403Gln missense mutation (alpha-MHC403/+) display a phenotype characteristic of familial hypertrophic cardiomyopathy (FHC). Male and female (30 +/- 8 week old) heterozygous alpha-MHC403/+ mice and litter-mate controls were evaluated using a surface electrocardiogram (ECG) and an in vivo cardiac electrophysiology study (EPS). Wild type animals had normal intracardiac electrophysiology, with no significant differences between male and female control mice during EPS. The female wild-type mice did have slower heart rates and longer ECG intervals than their male wild-type counterparts. The female alpha-MHC403/+ mice had similar ECG's, cardiac conduction times, and refractory periods compared with female wild-type mice. In contrast, male FHC mice had distinctive ECG and electrophysiologic abnormalities including right axis deviation, prolonged ventricular repolarization and prolonged sinus node recovery times. During programmed ventricular stimulation, 62% of male alpha-MHC403/+ mice and 28% of female alpha-MHC403/+ mice had inducible ventricular tachycardia. These studies identify gender-specific electrophysiologic abnormalities in alpha-MHC403/+ FHC mice, concordant with the histological and hemodynamic derangements previously reported. Heterozygous mice bearing an Arg403Gln missense mutation in the alpha cardiac myosin heavy chain gene (alpha-MHC403/+) exhibit the histopathologic features of human familial hypertrophic cardiomyopathy. Surprisingly, homozygous alpha-MHC403/403 mice die by postnatal day 8. Here we report that neonatal lethality is caused by a fulmit dilated cardiomyopathy characterized by myocyte dysfunction and loss. Heart tissues from neonatal wild-type and alpha-MHC403/403 mice demonstrate equivalent switching of MHC isoforms; alpha isoforms in each increase from 30% at birth to 70% by day 6. Cardiac dimensions and function, studied for the first time in neonatal mice by high frequency (45 MHz) echocardiography, were normal at birth. Between days 4 and 6, alpha-MHC403/403 mice developed a rapidly progressive cardiomyopathy with left ventricular dilation, wall thinning, and reduced systolic contraction. Histopathology revealed myocardial necrosis with dystrophic calcification. Electron microscopy showed normal architecture intermixed with focal myofibrillar disarray. We conclude that 45-MHz echocardiography is an excellent tool for assessing cardiac physiology in neonatal mice and that the concentration of Gln403 alpha cardiac MHC in myocytes influences both cell function and cell viability. We speculate that variable incorporation of mutant and normal MHC into sarcomeres of heterozygotes may account for focal myocyte death in familial hypertrophic cardiomyopathy. Patients with familial hypertrophic cardiomyopathy (FHC) are at risk for ventricular arrhythmias and sudden death. Regional variability in the QT interval [QT dispersion (QTd)] is significantly increased in humans with FHC and ventricular arrhythmias. A mouse model of FHC resulting from a mutation in the alpha-myosin heavy-chain (Arg403Gln) was used to study the electrophysiologic phenotype of this disease. Cardiac electrophysiology studies and surface ECGs were performed in FHC mice and wild-type controls to evaluate the feasibility and significance of QTd measurements in predicting the risk for ventricular arrhythmias. Atrial and ventricular pacing electrodes were placed by either a transvenous or epicardial approach. Standard pacing and extrastimulus protocols were followed. The QT interval was measured in six surface ECG leads. QTd was defined as the difference between the maximum and minimum measured QT intervals. Male FHC mice had greater QTd than wild-type controls (37.1 +/- 3.0 ms versus 23.9 +/- 1.9 ms, p = 0.001). There was also a significant gender difference in QTd within each genotype; female wild-type mice had greater QTd than male wild-type mice (37.4 +/- 5.3 ms versus 23.9 +/- 1.9 ms, p = 0.005), and male FHC mice had greater QTd than female FHC mice (37.1 +/- 3.0 ms versus 27.2 +/- 2.0 ms, p = 0.02). Twelve of 23 FHC mice had inducible ventricular arrhythmias, whereas only 2 of 32 wild-type mice were inducible (p = 0.004). Although a significantly increased number of FHC mice had arrhythmias compared with wild-type mice, QTd did not correlate with arrhythmia inducibility. The importance of this study is that it validates the mouse model for further investigation of arrhythmogenic risk and gender differences in the electrophysiologic phenotype in FHC. It also suggests that although gender- and genotype-specific QTd values are increased, they do not predict arrhythmia risk in FHC mice. BACKGROUND: To understand further the pathogenesis of familial hypertrophic cardiomyopathy, we determined how the cardiomyopathy induced by an Arg403-->Gln missense mutation in the alpha-myosin heavy chain (403) is affected by chronically enhancing sympathetic drive by mating the mice with those overexpressing G(s)alpha (G(s)alpha x403). METHODS AND RESULTS: Heart rate in 3-month-old conscious mice was elevated similarly (P<0.05) in mice overexpressing G(s)alpha (G(s)alpha mice; 746 +/- 14 bpm) and G(s)alpha x403 mice (718+/- 19 bpm) compared with littermate wild-type mice (WT; 623+/- 18 bpm) and 403 mice (594+/- 16 bpm). Left ventricular ejection fraction (LVEF), as determined by echocardiography, was enhanced in G(s)alpha x403 mice (88+/- 1%, P<0.001) compared with WT (69+/- 1%), 403 (75+/- 1%), and G(s)alpha (69 +/- 2%) mice. Isolated cardiomyocytes from G(s)alpha x403 mice also exhibited higher (P<0.001) baseline percent contraction (11.9+/- 0.5%) than WT (7.0+/- 0.5%), 403 (5.5+/- 0.5%), and G(s)alpha (7.8+/- 0.3%) cardiomyocytes. Relaxation of myocytes was impaired in 403 mice compared with WT but enhanced in G(s)alpha and normalized in G(s)alpha x403 mice. This was also observed in vivo. In vivo isoproterenol (0.1 microgram . kg(-1) . min(-1)) increased LVEF to maximal levels in G(s)alpha x403 and G(s)alpha, whereas in 403, the response was attenuated compared with WT. At 10 months of age, G(s)alpha x403 had significantly depressed LVEF (57 +/- 4%). Histopathological examination demonstrated that myocyte hypertrophy and fibrosis were already present in young G(s)alpha x403 mice and that old animals had severe cardiomyopathy. By 15 months of age, the survival of G(s)alpha x403 was 0% compared with 100% for WT, 71% for G(s)alpha, and 100% for 403 mice (P<0.05). CONCLUSIONS: These results show that the cardiomyopathy developed by G(s)alpha x403 mice is synergistic rather than additive, most likely owing to the elevated baseline function combined with enhanced responsiveness to sympathetic stimulation. BACKGROUND: Mutations in the beta-myosin heavy-chain (betaMyHC) gene cause hypertrophic (HCM) and dilated (DCM) forms of cardiomyopathy. In failing human hearts, downregulation of alphaMyHC mRNA or protein has been correlated with systolic dysfunction. We hypothesized that mutations in alphaMyHC could also lead to pleiotropic cardiac phenotypes, including HCM and DCM. METHODS AND RESULTS: A cohort of 434 subjects, 374 (134 affected, 214 unaffected, 26 unknown) belonging to 69 DCM families and 60 (29 affected, 30 unaffected, 1 unknown) in 21 HCM families, was screened for alphaMyHC gene (MYH6) mutations. Three heterozygous MYH6 missense mutations were identified in DCM probands (P830L, A1004S, and E1457K; 4.3% of probands). A Q1065H mutation was detected in 1 of 21 HCM probands and was absent in 2 unaffected offspring. All MYH6 mutations were distributed in highly conserved residues, were predicted to change the structure or chemical bonds of alphaMyHC, and were absent in at least 300 control chromosomes from an ethnically similar population. The DCM carrier phenotype was characterized by late onset, whereas the HCM phenotype was characterized by progression toward dilation, left ventricular dysfunction, and refractory heart failure. CONCLUSIONS: This study suggests that mutations in MYH6 may cause a spectrum of phenotypes ranging from DCM to HCM. Male but not female mice carrying a single R403Q missense allele for cardiac alpha-myosin heavy chain (M-alphaMHC(R403Q/+) and F-alphaMHC(R403Q/+), respectively) develop significant hypertrophic cardiomyopathy (HCM) compared with male and female wild-type mice (M-alphaMHC(+/+) and F-alphaMHC(+/+), respectively) after approximately 30 wk of age. We tested the hypothesis that myofilament mechanical performance differs between M-alphaMHC(R403Q/+) and F-alphaMHC(R403Q/+) at younger ages (10-20 wk) and could account for sex differences in HCM development. The sensitivity of chemically skinned myocardial strips to Ca(2+) activation (pCa(50)) was significantly (P < 0.05) enhanced in male mice independent of genotype (M-alphaMHC(R403Q/+): 5.70 +/- 0.06, M-alphaMHC(+/+): 5.63 +/- 0.05, F-alphaMHC(R403Q/+): 5.57 +/- 0.03, F-alphaMHC(+/+): 5.54 +/- 0.04) by two-way ANOVA, whereas maximum developed tension was significantly enhanced in alpha-MHC(R403Q/+) independent of sex (M-alphaMHC(R403Q/+): 29.3 +/- 2.3, M-alphaMHC(+/+): 26.0 +/- 1.4, F-alphaMHC(R403Q/+): 30.2 +/- 2.1, F-alphaMHC(+/+): 26.2 +/- 1.2 mN/mm(2)). The frequency of maximum work generated by sinusoidal length perturbation was significantly higher in alphaMHC(R403Q/+) mice than in sex-matched controls (M-alphaMHC(R403Q/+): 2.26 +/- 0.47, M-alphaMHC(+/+): 1.29 +/- 0.18, F-alphaMHC(R403Q/+): 3.21 +/- 0.33, F-alphaMHC(+/+): 2.52 +/- 0.36 Hz). Unloaded shortening velocity was significantly enhanced in alphaMHC(R403Q/+) and in female mice (M-alphaMHC(R403Q/+): 2.26 +/- 0.47, M-alphaMHC(+/+): 1.29 +/- 0.18, F-alphaMHC(R403Q/+): 3.21 +/- 0.33, F-alphaMHC(+/+): 2.52 +/- 0.36 muscle lengths/s), and normalized mechanical power, calculated from the tension-velocity relationship, was significantly enhanced in alphaMHC(R403Q/+) independent of sex (M-alphaMHC(R403Q/+): 60 +/- 2 10(-3), M-alphaMHC(+/+): 37 +/- 3 10(-3), F-alphaMHC(R403Q/+): 57 +/- 3 10(-3), F-alphaMHC(+/+) 25 +/- 3 10(-3) muscle lengths/s x normalized tension). We did not find a statistically significant sex x mutation interaction for any measure of myofilament performance. Therefore, sarcomeric incorporation of the R403Q myosin similarly enhanced left ventricular myofilament mechanical performance in both male and female mice. The sex-dependent development of HCM due to the R403Q myosin may then be inhibited by female sex hormones, which may additionally underlie the observed sex differences for pCa(50) and unloaded shortening velocity. BACKGROUND: Familial hypertrophic cardiomyopathy (FHC) is characterized by genetic and clinical heterogeneity. Five percent of FHC families have 2 FHC-causing mutations, which results in earlier disease onset, increased cardiac dysfunction, and a higher incidence of sudden death events. These observations suggest a relationship between the number of gene mutations and phenotype severity in FHC. METHODS AND RESULTS: We sought to develop, characterize, and investigate the pathogenic mechanisms in a double-mutant murine model of FHC. This model (designated TnI-203/MHC-403) was generated by crossbreeding mice with the Gly203Ser cardiac troponin I (TnI-203) and Arg403Gln alpha-myosin heavy chain (MHC-403) FHC-causing mutations. The mortality rate in TnI-203/MHC-403 mice was 100% by age 21 days. At age 14 days, TnI-203/MHC-403 mice developed a significantly increased ratio of heart weight to body weight, marked interstitial myocardial fibrosis, and increased expression of atrial natriuretic factor and brain natriuretic peptide compared with nontransgenic, TnI-203, and MHC-403 littermates. By age 16 to 18 days, TnI-203/MHC-403 mice rapidly developed a severe dilated cardiomyopathy and heart failure, with inducibility of ventricular arrhythmias, which led to death by 21 days. Downregulation of mRNA levels of key regulators of Ca(2+) homeostasis in TnI-203/MHC-403 mice was observed. Increased levels of phosphorylated STAT3 were observed in TnI-203/MHC-403 mice and corresponded with the onset of disease, which suggests a possible cardioprotective response. CONCLUSIONS: TnI-203/MHC-403 double-mutant mice develop a severe cardiac phenotype characterized by heart failure and early death. The presence of 2 disease-causing mutations may predispose individuals to a greater risk of developing severe heart failure than human FHC caused by a single gene mutation. Although familial hypertrophic cardiomyopathy (FHC) is characterized as cardiac disease in the absence of overt stressors, disease penetrance, and pathological progression largely depend on modifying factors. Accordingly, pressure overload by transverse aortic constriction (TAC) was induced in 2-month-old, male mice with and without a FHC (R403Q) mutation in α-myosin heavy chain. A significantly greater number of FHC mice (n = 8) than wild-type (WT) mice (n = 5) died during the 9-week study period. TAC induced a significant increase in cardiac mass whether measured at 2 or 9 weeks post-TAC in both WT and FHC mice, albeit to a different extent. However, the temporal and morphological trajectory of ventricular remodeling was impacted by the FHC transgene. Both WT and FHC hearts responded to TAC with an early (2 weeks post-TAC) and significant augmentation of the relative wall thickness (RWT) indicative of concentric hypertrophy. By 9 weeks post-TAC, RWT decreased in WT hearts (eccentric hypertrophy) but remained elevated in FHC hearts. WT hearts following TAC demonstrated enhanced cardiac function as measured by the end-systolic pressure-volume relationship, pre-load recruitable stroke work (PRSW), and myocardial relaxation indicative of compensatory hypertrophy. Similarly, TAC induced differential histological and cellular remodeling; TAC reduced expression of the sarcoplasmic reticulum Ca(2+)-ATPase (2a) (SERCA2a; 2 and 9 weeks) and phospholamban (PLN; 2 weeks) but increased PLN phosphorylation (2 weeks) and β-myosin heavy chain (β-MyHC; 9 weeks) in WT hearts. FHC-TAC hearts showed increased β-MyHC (2 and 9 weeks) and a late (9 weeks) decrease in PLN expression concomitant with a significant increase in PLN phosphorylation. We conclude that FHC hearts respond to TAC induced pressure overload with increased premature death, severe concentric hypertrophy, and a differential ability to undergo morphological, functional, or cellular remodeling compared to WT hearts.

Which are the cardiac manifestations of Marfan syndrome?

Cardiac manifestations of Marfan syndrome include aortic root dilation,aortic regurgitation, mitral valve prolapse and mitral valve regurgitation.

Marfan's syndrome in its complete and incomplete forms takes very often a course with cardiac complications, predetermining the fate of such patients. The incomplete forms often present difficulties for the timely etiological elucidation of the cardiac changes leading to a retardation in the prescribing a rational regime to the patients and timeliness of the operation treatment. The authors' team own observations are reported on 10 patients with Marfan's syndrome, one with complete form and nine--incomplete forms, all of them with cardiac complications; two with mitral insufficiency, three with aortic insufficiency, four with aortic and mitral insufficiency and one with aortic, mitral and tricuspidal insufficiency; seven of the patients had aneurysm at the initial part of the aorta, manifested to various degrees and one--dysplasia of aorta. Rhythm disturbances were found in one of the patients. One of the patients underwent operation--prosthesis of mitral and aortic valve--with good results. Three of them died of severe total cardiac insufficiency. Echocardiographic and clinical evaluation was undertaken in 33 adult patients with Marfan syndrome. Cardiovascular manifestations were found in 32 (97%), mitral valve prolapse in 23 (70%) and dilated aortic root (> or = 21 mm/m2) in 26 patients (79%). The aortic root diameter was 58-85 mm in six patients with proximal aortic dissection, 57-76 mm in four patients undergoing elective surgery and 35-49 mm in conservatively treated patients. Average age at surgery was 28 years. Echocardiography with Doppler is the method of choice for diagnosis and control of patients with Marfan syndrome. The Marfan syndrome is an autosomal domit disorder of the connective tissue with mutations on the fibrillin-1 gene encoding for fibrillin, a major component of the extracellular microfibrils. The prevalence of the syndrome is 7-17/100,000. The mean life expectancy for untreated patients with Marfan syndrome is 32 years with aortic dissection, aortic rupture or cardiac failure due to mitral and aortic valve regurgitation as the predomit cause of death in > 90% of the cases. In severely affected cases with neonatal Marfan syndrome, patients are likely to survive only a few months. According to the literature database the prevalence of aortic dilatation is 76%, 26% for aortic regurgitation, 62% for mitral valve prolapse, and 29% for mitral valve regurgitation in adult patients with classic Marfan syndrome. Pathogenesis and the natural cause of each cardiovascular manifestation is thoroughly discussed with the problems resulting from associated cardiac arrhythmias, sudden cardiac death, endocarditis, and less frequent cardiovascular manifestations of the Marfan syndrome. Special focus is placed on the analysis of cardiovascular complications during pregcy. Marfan's syndrome is a disease of collagen microfibrils, the essential composition of which, fibrillin, is defective. The coding gene of this large protein has been localised on chromosome 15 and partially cloned. Its mutation is transmitted in the autosomal domit mode. It is common, affects many organs, especially those rich in collagen. They include the skeleton, the eye and cardiovascular system. The prognosis of these patients depends on the degree of cardiovascular involvement; the aorta is the principal site of the lesions, particularly the aortic root which tends to develop aneurysmal dilatation, then dissection, the main cause of premature death of these patients. Mitral valve prolapse giving rise to mitral regurgitation may also be observed. Much progress has been made is recent years in the management of Marfan's syndrome, especially in ultrasound follow-up of the aortic root and the definition of risk factors for dissection. In parallel, advances have been made in the treatment, both medical with the use of betablockers to try to slow progression to aneurysm, and surgical, in replacement of the aorta and aortic valve in time and under optimal conditions. Life expectancy is thereby significantly increased. Similar progress has been made to allow these patients to have a pregcy, classically thought to carry a high risk of maternal death. AIMS: To investigate the natural history of mitral valve and aortic abnormalities in patients with Marfan syndrome during childhood and adolescence. METHODS: Fifty two patients with Marfan syndrome were followed for a mean of 7.9 years. Occurrence of adverse cardiovascular outcomes was measured clinically and by ultrasound examination. RESULTS: Mitral valve prolapse (MVP) was diagnosed in 46 patients at a mean age of 9.7 years, more than 80% of whom presented as "silent MVP". Mitral regurgitation (MR) occurred in 25 patients, aortic dilatation in 43, and aortic regurgitation (AR) in 13. Both MVP and aortic dilatation developed at a constant rate during the age period 5-20 years. In 23 patients MVP was diagnosed before aortic dilatation, in 18 the reverse occurred, and in 11 patients the two abnormalities were diagnosed simultaneously. During follow up, 21 patients showed progression of mitral valve dysfunction; progression of aortic abnormalities occurred in 13. Aortic surgery was performed in 10; two died of subsequent complications. Mitral valve surgery was performed in six. In sporadic female Marfan patients the age at initial diagnosis of MVP, MR, aortic dilatation, and AR was lowest, the grade of MR and AR most severe, the time lapse between the occurrence of MVP and subsequent MR as well as between dilatation and subsequent AR shortest, and the risk for cardiovascular associated morbidity and mortality highest. CONCLUSIONS: During childhood and adolescence in Marfan syndrome, mitral valve dysfunction as well as aortic abnormalities develop and progress gradually, often without symptoms, but may cause considerable morbidity and mortality by the end of the second decade, especially in female sporadic patients. INTRODUCTION: Cardiovascular complications are the major cause of morbidity and mortality in Marfan syndrome (MS), a common connective tissue disorder. Currently it is considered that the prognosis and morphologic characteristics in infantile Marfan syndrome may be quite different from those reported in older patients. The objective of this study was to analyze the cardiovascular manifestations and evolution of the patients with Marfan syndrome followed at our pediatric cardiac unit. METHODS: The authors reviewed the clinical files of all the patients that fulfilled the diagnostic criteria for MS according to De Paepe et al. (1996). We analyzed the following parameters: gender, age at referral, race, family history, clinical examination, diagnostic exams, therapy and evolution. The patients were divided into two groups according to the age at diagnosis: infants (group 1) and older patients (group 2). RESULTS: Group 1 included 3 infants, two boys and one girl, sporadic cases, presenting congestive heart failure. The major cardiac diagnoses were aortic dilatation (1/3) and mitral valve prolapse with severe mitral regurgitation (2/3). Congenital heart disease was associated in two cases (patent ductus arteriosus and atrial septal defect). Two needed cardiac surgery at an early age and one was recently proposed for surgery. There were no deaths. Group 2 included 20 patients, 14 boys and 6 girls, first seen at a mean age of 8 years. Ten had a positive family history and none presented cardiac symptoms. The major cardiac manifestations were mitral valve prolapse (18/20) and aortic dilatation (17/20). There was no significant progression of the cardiac lesions, except for one case, during the 12 years of follow-up. CONCLUSION: Infantile MS presented high morbidity; mitral regurgitation was severe in two cases. All patients presented heart failure, two needing early operations. In classic MS evolution was favorable, and the commonest cardiac lesions were mitral valve prolapse and aortic dilatation. We emphasize the need for beta-blockers to prevent progression of aortic dilatation. The decision for surgery rests upon the severity of valve regurgitation and the rate of progression of aortic dilatation. It is important to inform patients and family about physical exercise, prevention of endocarditis, risks associated with pregcy and genetic counseling. BACKGROUND: Marfan syndrome is an inherited connective tissue disorder with an autosomic domit transmission. The prevalence is 1:5000-10 000 and the clinical major criteria involve the skeletal and ocular apparatus and the cardiovascular and central nervous system. The main cause of morbidity is represented by the thoracic aortic dissection/aneurysm that is responsible for 80% of the deaths. METHODS: We performed a clinical study on 227 patients enrolled at our Clinical and Research Marfan and Related Disorders Center. The aim of this study was to describe the prevalence of cardiovascular manifestation in this cohort of patients. RESULTS: Aortic dilation was present in 172 patients (75.8%), mitral valve prolapse in 179 (78.9%). Aortic insufficiency was present in 83 patients (36.6%), mitral insufficiency in 165 (72.7%). When analyzed separately, in < 10-year and > 40-year patients aortic dilation was more prevalent than mitral valve prolapse. Three patients presented with interatrial septal defect, 4 aortic bicuspid valve; 23 had a history of ventricular and supraventricular arrhythmias, and in 2 patients an implantable cardioverter device had been implanted. Fifty-seven patients were treated with beta-blockers and 28 had been operated for aortic aneurysmal dilation. CONCLUSIONS: In Marfan syndrome mitral valve prolapse and aortic dilation are the main cardiovascular manifestations, interatrial septal defect and aortic bicuspid valve had the same prevalence than in subjects without Marfan syndrome. These data refer to our first patient evaluation; further studies are needed to evaluate the progression and the natural history of cardiovascular manifestations in Marfan syndrome. Marfan syndrome is a domitly inherited connective tissue disease characterized by cardiovascular, skeletal and ocular manifestations, which was firstly described by Antoine Marfan in 1896. The underlying disorder is a mutation, which impairs fibrillin synthesis and is associated with the FBN-1 gene on the 15th chromosome. Ghent Nosology is used for diagnosis. The progressive dilatation of the proximal aorta leading to dissection and rupture is the typical feature of the disease. Aortic aneurysm and aortic rupture are the lethal complications of the disorder. Increased life expectancy depends on the control and the prevention of the cardiovascular complications. The most frequent cardiovascular manifestation is the mitral valve involvement. The principal pathologic findings on the mitral valve are annular dilatation, fibromyxomatous changes of the leaflets and chordae, elongation and rupture of chordae and deposition of calcium. Prolapsus occurs in 80% of the cases. Elective surgery with optimal timing is associated with increased survival. In the follow-up of patients after surgery for aortic aneurysm and dissection, serial imaging studies in order to detect a new onset aneurysm or dissection on different sites of the aorta are essential. Marfan syndrome (MFS) is a systemic disorder of connective tissue with autosomal domit inheritance. The diagnosis of MFS is based on the identification of a combination of clinical manifestations in the ocular, musculoskeletal, and cardiovascular organ systems defined in the Ghent Nosology (De Paepe et al, 1996). Confirmation of the diagnosis in an individual requires the presence of major clinical manifestations in at least two organ systems associated with involvement of a third organ system. In relatives of an affected proband, major involvement of one organ system and involvement of a second organ system confirms the diagnosis. Major clinical criteria are very specific for MFS and include a combination of (4 out of 8) skeletal manifestations, ectopia lentis, dural ectasia and dilatation or dissection of the ascending aorta. The prevalence of- and the guidelines for the assessment of each of these major criteria are well established. Minor clinical criteria are less typical, but their importance in the diagnostic process should not be underestimated. Unfortunately, figures on the prevalence as well as practical guidelines for the assessment of most minor criteria are lacking, especially for those involving the cardiovascular system. The major cardiovascular manifestation in MFS is a progressive dilatation of the ascending aorta, leading to aortic aneurysm formation and eventually to fatal aortic rupture or dissection. Aortic dissection in early adult life is the leading cause of death in MFS. Early diagnosis of individuals at risk of the disease is extremely important as timely treatment of cardiovascular complications has greatly improved life expectancy in MFS. Despite progress in medical and surgical treatment of aortic aneurysms, MFS continues to be associated with significant morbidity and mortality. This may be related to inadequate diagnosis or treatment, but also to the occurrence of cardiovascular problems in ageing MFS patients that were unrecognised until now, such as left ventricular (LV) dysfunction.This thesis is focused on the study of cardiovascular manifestations of MFS which localize beyond the aortic root and on the presently unknown relationship between the severity of the cardiovascular phenotype and the genotype. In the first part, we have studied the prevalence and diagnostic value of the following cardiovascular manifestations of MFS: mitral valve prolapse (MVP) and calcification of the mitral valve annulus, dilatation of the main pulmonary artery (MPA) and dilatation or dissection of the descending aorta. We found a significantly higher prevalence of MVP in MFS patients compared to normal controls, indicating that this feature is useful in the diagnostic evaluation of the condition. In contrast, calcification of the mitral valve annulus appears to be very uncommon, difficult to quantify and therefore not useful in the diagnosis of MFS. We also studied the dimension of the MPA in a series of MFS patients and defined a cut-of value that can be used in the diagnostic evaluation of adult MFS patients. In addition, we showed that diameters of the aorta measured at different levels beyond the aortic root are increased in MFS patients compared to controls. Unfortunately, there was too much overlap with the values obtained in the normal control population to provide cut-off values for the descending aorta. Based on these findings, we developed practical guidelines for the cardiovascular evaluation of patients referred for MFS. In the second part, we studied LV function in MFS patients free of valvular heart disease using a combination of echocardiography (both conventional echocardiography and tissue Doppler imaging) and Magnetic Resoce Imaging. We could demonstrate that MFS patients present a combination of systolic and diastolic dysfunction that is not related to valvular heart disease. This may be attributed to a primary contractile dysfunction of the myocardium and is likely related to the underlying alterations in the elastic features of the myocardium, resulting from the microfibrillar defect. This observation is important in the development of new therapeutic strategies for MFS. Affected individuals may benefit from a treatment with agents that support myocardial function such as angiotensin converting enzyme--inhibitors or angiotensin II type-1 receptor blockers. Furthermore, since MFS patients survive longer thanks to improved medical and surgical treatments, LV dysfunction may become an important issue in the follow-up of these patients. In the third part, we have studied aspects of local and global wave reflection in the aorta of MFS patients. Early return of reflected waves boosts systolic pressure and presents an extra load for the heart and the central vessels. As such, these wave reflections are regarded as one of the important determits of central blood pressure and can contribute to the development of aortic dilatation in MFS. However, we were unable to demonstrate clear differences in both local and global parameters of wave reflection between MFS patients and normal controls. This could be explained by the fact that increased length of the aorta on the one hand and increased aortic stiffness on the other hand counterbalance each other in MFS patients without yielding any net effect on wave reflection. In the last part of this thesis, we investigated the correlation between the severity of the cardiovascular phenotype in MFS and the type of FBN1 mutation. First, we investigated the correlation between parameters of aortic stiffness (distensibility and pulse wave velocity measured by Magnetic Resoce Imaging) and the type of FBN1 mutation (missense or in-frame deletions/insertions versus nonsense or out-of-frame deletions/insertions). We could not demonstrate any significant differences between these different mutation types, indicating that the FBN1 genotype is not the sole determit of aortic stiffness. Second, we provided a detailed description of clinical findings in three unrelated MFS families in which an FBN1 mutation was identified and which demonstrate striking intrafamilial phenotypic variability as another illustration of the absence of genotype/phenotype correlations in MFS. This study also illustrated several important issues in MFS. First, repeated clinical examination of suspected patients can be necessary in order to establish a correct and final diagnosis. Second, extensive family history taking and clinical examination of first degree relatives can be highly contributory to the diagnosis. Third, patients with an 'atypical' MFS phenotype may show substantial clinical overlap with other connective tissue disorders such as Weill-Marchesani syndrome or Ehlers-Danlos syndrome and represent a diagnostic challenge. We demonstrated that additional mutational analysis of the FBN1 gene can be a valuable aid to the diagnosis and help to outline medical management options in these challenging cases. In conclusion, we have refined diagnostic guidelines for the assessment of minor cardiovascular manifestations in MFS, shown that LV dysfunction is part of the cardiovascular spectrum and should be followed in the management of MFS patients, and demonstrated that aortic wave reflection is not elevated in MFS. In this work, we also investigated genotype/phenotype correlations, illustrated the marked (intrafamilial) variability in phenotypic expression of the condition, and the value of molecular testing in the diagnosis of MFS. Overall, this thesis nicely illustrates that close interaction and collaboration between cardiology and genetics is an added value to the study of disease pathogenesis of MFS and aortic aneurysms in general. BACKGROUND: The typical cardiac manifestations of Marfan syndrome are aortic regurgitation with progressive dilatation of the aortic root, which may cause dissection and rupture of the ascending aorta, mitral valve prolapse and mitral valve regurgitation. In this study, we aimed to show echocardiographic findings in 11 patients with Marfan syndrome. METHODS: Diagnosis of Marfan syndrome was based on the Ghent criteria. All patients had a full echocardiographic evaluation. During the evaluation, we investigated the presence of mitral valve prolapse, mitral valve regurgitation, tricuspid valve prolapse, dilatation of the aortic root, and aortic regurgitation. RESULTS: Eleven patients were diagnosed as Marfan syndrome (seven male, four female, age 4-14 years). All had mitral valve prolapse (nine with mitral valve regurgitation). Among these 11 patients, seven had accompanying tricuspid valve prolapse, six had dilatation of the aortic root and two had aortic regurgitation. CONCLUSION: Eleven patients in our clinic were diagnosed as Marfan syndrome since they had distinct characteristics of marfanoid phenotype. Echocardiographic evaluation of these patients showed marked heart valve involvement. In Marfan syndrome, it is known that the aortic valve is affected following mitral valve involvement. In our experience, aortic root dilatation is less common. However, particular attention should be given to following up aortic root status with noninvasive echocardiography to institute measures to prevent complications. Inherited connective tissue diseases such as Marfan syndrome are frequently associated with cardiovascular manifestations. Aortic involvement with dilation and dissection is the most common finding and the major cause of death in Marfan syndrome patients. We report the echocardiographic study of a 53-year-old male patient with uncommon coexistence of cardiovascular abnormalities typical of connective tissue disease at first clinical presentation in acute clinical setting: dissection of the descending aorta associated with severe mitral regurgitation due to leaflet flail and massive aortic insufficiency due to ascending aortic enlargement, leading to left ventricular dilation and dysfunction. BACKGROUND: Cardiac manifestations of Marfan syndrome include aortic root dilation and mitral valve prolapse (MVP). Only scant data exist describing MVP in patients with Marfan syndrome undergoing aortic root replacement. METHODS AND RESULTS: We retrospectively analyzed data from 166 MFS patients with MVP who were enrolled in a prospective multicenter registry of patients who underwent aortic root aneurysm repair. Of these 166 patients, 9% had mitral regurgitation (MR) grade >2, and 10% had MR grade 2. The severity of MVP and MR was evaluated by echocardiography preoperatively and ≤ 3 years postoperatively. Forty-one patients (25%) underwent composite graft aortic valve replacement, and 125 patients (75%) underwent aortic valve-sparing procedures; both groups had similar prevalences of MR grade >2 (P=0.7). Thirty-three patients (20%) underwent concomitant mitral valve (MV) intervention (repair, n=29; replacement, n=4), including all 15 patients with MR grade >2. Only 1 patient required MV reintervention during follow-up (mean clinical follow-up, 31 ± 10 months). Echocardiography performed 21 ± 13 months postoperatively revealed MR >2 in only 3 patients (2%). One early death and 2 late deaths occurred. CONCLUSIONS: Although the majority of patients with Marfan syndrome who undergo elective aortic root replacement have MVP, only 20% have concomitant MV procedures. These concomitant procedures do not seem to increase operative risk. In patients with MR grade ≤ 2 who do not undergo a concomitant MV procedure, the short-term incidence of progressive MR is low; however, more follow-up is needed to determine whether patients with MVP and MR grade ≤ 2 would benefit from prophylactic MV intervention. PURPOSE: Marfan syndrome (MFS) is a genetic disorder of the connective tissue. Aortic root dilation is a main criterion of the Ghent Nosology. Dural ectasia and the presence of mitral valve prolapse (MVP) contribute to its systemic score. The purpose of this study was to investigate the frequency of dural ectasia and its correlation with cardiovascular manifestations in a pediatric study population. PATIENTS AND METHODS: 119 pediatric patients with confirmed or suspected MFS were examined in the local Marfan Clinic. 31 children with MFS who underwent magnetic resoce imaging (MRI) were included. Each patient was evaluated according to the Ghent nosology. Echocardiography was used to measure the aortic root diameter and assess the presence of MVP and mitral regurgitation. Z-scores were calculated for the evaluation of the aortic root diameters. MRI was performed to determine the dural sac ratio (DSR). RESULTS: The prevalence of dural ectasia was 90.3 %, of aortic root dilation 32.2 %, of MVP 64.5 % and of mitral regurgitation 51.6 %. DSR at L5 correlated with the intraindividual z-scores (slope, 3.62 ± 1.5 [0.56; 6.68]; r = 0.17; p = 0.02; F = 5.84). Z-scores ≥ 2 were accompanied by dural ectasia in 100 %, MVP in 95 % and mitral regurgitation in 100 % of cases. MVP was accompanied by mitral regurgitation in 70 % of cases. CONCLUSION: As the examined cardiac manifestations show a coincidence with dural ectasia in 95 - 100 % of cases, MRI for diagnostic dural sac imaging should be reserved for MFS suspicions with the absence of those manifestations in order to establish the diagnosis according to the Ghent criteria. Thus, the present study supports the recent downgrading of dural ectasia to a contributor to the systemic score.

How is connected "isolated Non-compaction cardiomyopathy" with dilated cardiomyopathy?

Mutations in cardiac beta-myosin heavy chain and alpha-tropomyosin link isolated Non-compaction cardiomyopathy with dilated cardiomyopathy

BACKGROUND: Dilated cardiomyopathy (DCM) is characterized by idiopathic dilatation and systolic contractile dysfunction of the ventricle(s) leading to an impaired systolic function. The origin of DCM is heterogeneous, but genetic transmission of the disease accounts for up to 50% of the cases. Mutations in alpha-tropomyosin (TPM1), a thin filament protein involved in structural and regulatory roles in muscle cells, are associated with hypertrophic cardiomyopathy (HCM) and very rarely with DCM. METHODS AND RESULTS: Here we present a large four-generation family in which DCM is inherited as an autosomal domit trait. Six family members have a cardiomyopathy with the age of diagnosis ranging from 5 months to 52 years. The youngest affected was diagnosed with dilated and non-compaction cardiomyopathy (NCCM) and died at the age of five. Three additional children died young of suspected heart problems. We mapped the phenotype to chromosome 15 and subsequently identified a missense mutation in TPM1, resulting in a p.D84N amino acid substitution. In addition we sequenced 23 HCM/DCM genes using next generation sequencing. The TPM1 p.D84N was the only mutation identified. The mutation co-segregates with all clinically affected family members and significantly weakens the binding of tropomyosin to actin by 25%. CONCLUSIONS: We show that a mutation in TPM1 is associated with DCM and a lethal, early onset form of NCCM, probably as a result of diminished actin binding caused by weakened charge-charge interactions. Consequently, the screening of TPM1 in patients and families with DCM and/or (severe, early onset forms of) NCCM is warranted. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction.

What is the role of AMPK in diabetic cardiomyopathy?

AMPK activation protects cardiac structure and function by increasing cardiac autophagy in the diabetic heart. Decreased AMPK activity and the subsequent reduction in cardiac autophagy are central to the development of diabetic cardiomyopathy. In fact, dissociation of Bcl-2 from Beclin1 may be an important mechanism for preventing diabetic cardiomyopathy via AMPK activation that restores autophagy and protects against cardiac apoptosis. In addition, genetic inhibition of AMPK in cardiomyocytes attenuates cardiac autophagy, exacerbates cardiac dysfunction and increases mortality in diabetic mice. The modulation of AT-1R/AMPK-MAPK pathway might play crucial roles for the pathogenesis of diabetic cardiomyopathy and it could become an important therapeutic target to ameliorate the diabetic cardiomyopathy. Stimulation of AMPK by metformin or trimetazidine administration may represent a novel approach to treat diabetic cardiomyopathy.

In obese rodents, excess myocardial lipid accumulation (lipotoxicity) of myocardium may cause cardiomyopathy that in the obese Zucker diabetic fatty (ZDF) fa/fa rat can be prevented by treatment with troglitazone (TGZ). To determine the underlying mechanisms, we measured total 5'-AMP-activated kinase (AMPK) protein and its activated, phosphorylated form, P-AMPK. P-AMPK was significantly reduced in both ZDF fa/fa rat and ob/ob mouse hearts compared with lean, wild-type controls. TGZ treatment of obese ZDF rats, which lowered cardiac lipid content, increased P-AMPK. Expression of protein phosphatase 2C (PP2C), which inactivates AMPK activity by dephosphorylation, was increased in untreated ZDF fa/fa rat hearts, but fell with TGZ treatment, suggesting that PP2C can influence AMPK activity. In cultured myocardiocytes, fatty acids reduced P-AMPK, suggesting a feed-forward effect of lipid overload. Our findings highlight a role of PP2C and AMPK in the derangements of cardiac lipid metabolism in obesity and provide new insights as to the mechanisms of the liporegulatory disorder leading to lipotoxic cardiomyopathy. 5-[5-(2-Nitrophenyl) furfuryliodine]-1,3-diphenyl-2-thiobarbituric acid (UCF-101) is a protease inhibitor which was reported to protect against ischaemic heart damage and apoptosis. This study evaluated the impact of UCF-101 on steptozotocin (STZ)-induced diabetic cardiomyocyte dysfunction. Adult FVB mice were made diabetic with a single injection of STZ (200 mg kg(1)). Two weeks after STZ injection, cardiomyocytes from control and STZ-treated mice were isolated and treated with UCF-101 (20 mum for 1 h). Cardiomyocyte contractile properties were analysed, including peak shortening (PS), maximal velocity of shortening/relengthening (+/-dL/dt), time to PS (TPS) and time to 90% relengthening (TR(90)). Steptozotocin-induced diabetes depressed PS and +/-dL/dt and prolonged TPS and TR(90) in cardiomyocytes, all of which were significantly alleviated by UCF-101. Immunoblotting analysis showed that UCF-101 significantly alleviated STZ-induced loss of phospholamban phosphorylation without affecting sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2a) and phospholamban. Steptozotocin reduced AMP-activated protein kinase (AMPK) phosphorylation at Thr172 of the catalytic subunit without affecting total AMPK expression, which was restored by UCF-101. Short-term exposure to UCF-101 did not change the expression of X-linked inhibitor of apoptosis protein (XIAP) and Omi stress-regulated endoprotease, high temperature requirement protein A2 (Omi/HtrA2), favouring an apoptosis-independent mechanism. Both the AMPK activator resveratrol and the antioxidant N-acetylcysteine mimicked the UCF-101-induced beneficial effect in STZ-induced diabetic cardiomyocytes. In addition, UCF-101 promoted the phosphorylation of p38 mitogen-activated protein kinases and c-Jun N-terminal kinase (JNK) after 15 min of incubation, while it failed to affect the phosphorylation of extracellular signal-regulated kinase (ERK) and glycogen synthase kinase-3beta (GSK-3beta) within 120 min in H9C2 myoblasts. Taken together, these results indicate that UCF-101 protects against STZ-induced cardiomyocyte contractile dysfunction, possibly via an AMPK-associated mechanism. AIM: To investigate the influence of trimetazidine, which is known to be an antioxidant and modulator of metabolism, on cardiac function and the development of diabetic cardiomyopathy in db/db mouse. METHODS: Trimetazidine was administered to db/db mice for eight weeks. Cardiac function was measured by inserting a Millar catheter into the left ventricle, and oxidative stress and AMP-activated protein kinase (AMPK) activity in the myocardium were evaluated. RESULTS: Untreated db/db mice exhibited a significant decrease in cardiac function compared to normal C57 mice. Oxidative stress and lipid deposition were markedly increased in the myocardium, concomitant with inactivation of AMPK and increased expression of peroxisome proliferator-activated receptor coactivator-1 alpha (PGC-1 alpha). Trimetazidine significantly improved systolic and diastolic function in hearts of db/db mice and led to reduced production of reactive oxygen species and deposition of fatty acid in cardiomyocytes. Trimetazidine also caused AMPK activation and reduced PGC-1 alpha expression in the hearts of db/db mice. CONCLUSION: The data suggest that trimetazidine significantly improves cardiac function in db/db mice by attenuating lipotoxicity and improving the oxidation status of the heart. Activation of AMPK and decreased expression of PGC-1 alpha were involved in this process. Furthermore, our study suggests that trimetazidine suppresses the development of diabetic cardiomyopathy, which warrants further clinical investigation. OBJECTIVE: Autophagy is a critical cellular system for removal of aggregated proteins and damaged organelles. Although dysregulated autophagy is implicated in the development of heart failure, the role of autophagy in the development of diabetic cardiomyopathy has not been studied. We investigated whether chronic activation of the AMP-activated protein kinase (AMPK) by metformin restores cardiac function and cardiomyocyte autophagy in OVE26 diabetic mice. RESEARCH DESIGN AND METHODS: OVE26 mice and cardiac-specific AMPK domit negative transgenic (DN)-AMPK diabetic mice were treated with metformin or vehicle for 4 months, and cardiac autophagy, cardiac functions, and cardiomyocyte apoptosis were monitored. RESULTS: Compared with control mice, diabetic OVE26 mice exhibited a significant reduction of AMPK activity in parallel with reduced cardiomyocyte autophagy and cardiac dysfunction in vivo and in isolated hearts. Furthermore, diabetic OVE26 mouse hearts exhibited aggregation of chaotically distributed mitochondria between poorly organized myofibrils and increased polyubiquitinated protein and apoptosis. Inhibition of AMPK by overexpression of a cardiac-specific DN-AMPK gene reduced cardiomyocyte autophagy, exacerbated cardiac dysfunctions, and increased mortality in diabetic mice. Finally, chronic metformin therapy significantly enhanced autophagic activity and preserved cardiac functions in diabetic OVE26 mice but not in DN-AMPK diabetic mice. CONCLUSIONS: Decreased AMPK activity and subsequent reduction in cardiac autophagy are important events in the development of diabetic cardiomyopathy. Chronic AMPK activation by metformin prevents cardiomyopathy by upregulating autophagy activity in diabetic OVE26 mice. Thus, stimulation of AMPK may represent a novel approach to treat diabetic cardiomyopathy. We have recently shown that in diabetic OVE26 mice (type I diabetes), the AMP-activated protein kinase (AMPK) is reduced along with cardiac dysfunction and decreased cardiac autophagy. Genetic inhibition of AMPK in cardiomyocytes attenuates cardiac autophagy, exacerbates cardiac dysfunction and increases mortality in diabetic mice. More importantly, we have found chronic AMPK activation with metformin, one of the most used antidiabetes drugs and a well-characterized AMPK activator, significantly enhances autophagic activity, preserves cardiac function and prevents most of the primary characteristics of diabetic cardiomyopathy in OVE26 mice, but not in domit negative-AMPK diabetic mice. We conclude that AMPK activation protects cardiac structure and function by increasing cardiac autophagy in the diabetic heart. Toll-like receptor (TLR)4 regulates inflammation and metabolism and has been linked to the pathogenesis of heart disease. TLR4 is upregulated in diabetic cardiomyocytes, and we examined the role of TLR4 in modulating cardiac fatty acid (FA) metabolism and the pathogenesis of diabetic heart disease in nonobese diabetic (NOD) mice. Both wild-type (WT) NOD and TLR4-deficient NOD animals had increased plasma triglyceride levels after the onset of diabetes. However, by comparison, TLR4-deficient NOD mouse hearts had lower triglyceride accumulation in the early stages of diabetes, which was associated with a reduction in myeloid differentiation primary response gene (88) (MyD88), phosphorylation of p38 MAPK (phospho-p38), lipoprotein lipase (LPL), and JNK levels but increased phospho-AMP-activated protein kinase (AMPK). Oleic acid treatment in H9C2 cardiomyocytes also led to cellular lipid accumulation, which was attenuated by TLR4 small interfering RNA. TLR4 deficiency in the cells decreased FA-induced augmentation of MyD88, phospho-p38, and LPL, suggesting that TLR4 may modulate FA-induced lipid metabolism in cardiomyocytes. In addition, although cardiac function was impaired in both diabetic WT NOD and TLR4-deficient NOD animals compared with control nondiabetic mice, this deficit was less in the diabetic TLR4-deficient NOD mice, which had greater ejection fraction, greater fractional shortening, and increased left ventricular developed pressure in the early stages after the development of diabetes compared with their diabetic WT NOD counterparts. Thus, we conclude that TLR4 plays a role in regulating lipid accumulation in cardiac muscle after the onset of type 1 diabetes, which may contribute to cardiac dysfunction. Diabetic cardiomyopathy is associated with suppression of cardiac autophagy, and activation of AMP-activated protein kinase (AMPK) restores cardiac autophagy and prevents cardiomyopathy in diabetic mice, albeit by an unknown mechanism. We hypothesized that AMPK-induced autophagy ameliorates diabetic cardiomyopathy by inhibiting cardiomyocyte apoptosis and examined the effects of AMPK on the interaction between Beclin1 and Bcl-2, a switch between autophagy and apoptosis, in diabetic mice and high glucose-treated H9c2 cardiac myoblast cells. Exposure of H9c2 cells to high glucose reduced AMPK activity, inhibited Jun NH2-terminal kinase 1 (JNK1)-B-cell lymphoma 2 (Bcl-2) signaling, and promoted Beclin1 binding to Bcl-2. Conversely, activation of AMPK by metformin stimulated JNK1-Bcl-2 signaling and disrupted the Beclin1-Bcl-2 complex. Activation of AMPK, which normalized cardiac autophagy, attenuated high glucose-induced apoptosis in cultured H9c2 cells. This effect was attenuated by inhibition of autophagy. Finally, chronic administration of metformin in diabetic mice restored cardiac autophagy by activating JNK1-Bcl-2 pathways and dissociating Beclin1 and Bcl-2. The induction of autophagy protected against cardiac apoptosis and improved cardiac structure and function in diabetic mice. We concluded that dissociation of Bcl-2 from Beclin1 may be an important mechanism for preventing diabetic cardiomyopathy via AMPK activation that restores autophagy and protects against cardiac apoptosis. Diabetes induces cardiomyocyte apoptosis and suppresses cardiac autophagy, indicating that the interplay between autophagy and apoptotic cell death pathways is important in the pathogenesis of diabetic cardiomyopathy. The potential mechanism, however, remains unknown. We recently reported that diabetes depresses AMP-activated protein kinase (AMPK) activity, inhibits MAPK8/JNK1-BCL2 signaling, and promotes the interaction between BECN1 and BCL2. Concomitantly, diabetes induces cardiomyocyte apoptosis and suppresses cardiac autophagy. Activation of AMPK directly phosphorylates MAPK8, which mediates BCL2 phosphorylation and subsequent BECN1-BCL2 dissociation, leading to restoration of cardiac autophagy, protection against cardiac apoptosis, and ultimately improvement in cardiac structure and function. We conclude that dissociation of BCL2 from BECN1 through activation of MAPK8-BCL2 signaling may be an important mechanism by which AMPK activation restores autophagy, protects against cardiac apoptosis, and prevents diabetic cardiomyopathy.

Are circRNAs associated with diseases and traits?

Yes. Circular RNAs (circRNAs) play a crucial role in fine tuning the level of miRNA mediated regulation of gene expression by sequestering the miRNAs. Their interaction with disease associated miRNAs indicates that circular RNAs are important for disease regulation.

Circular RNAs are new players in regulation of post transcriptional gene expression. Animal genomes express many circular RNAs from diverse genomic locations. A recent study has validated a fairly large number of circular RNAs in human, mouse, and nematode. Circular RNAs play a crucial role in fine tuning the level of miRNA mediated regulation of gene expression by sequestering the miRNAs. Their interaction with disease associated miRNAs indicates that circular RNAs are important for disease regulation. In this paper we studied the potential association of circular RNAs (circRNA) with human diseases in two different ways. Firstly, the interactions of circRNAs with disease associated miRNAs were identified, following which the likelihood of a circRNA being associated with a disease was calculated. For the miRNAs associated with individual diseases, we constructed a network of predicted interactions between the miRNAs and protein coding, long non-coding and circular RNA genes. We carried out gene ontology (GO) enrichment analysis on the set of protein coding genes in the miRNA- circRNA interactome of individual diseases to check the enrichment of genes associated with particular biological processes. Secondly, disease associated SNPs were mapped on circRNA loci, and Argonaute (Ago) interaction sites on circular RNAs were identified. We compiled a database of disease-circRNA association in Circ2Traits (http://gyanxet-beta.com/circdb/), the first comprehensive knowledgebase of potential association of circular RNAs with diseases in human.

Which is the most common cause of sudden cardiac death in young athletes?

the most common cause of sudden cardiac death in young athletes is hypertrophic cardiomyopathy

Sudden death in athletes is a rare but tragic occurrence. Congenital cardiovascular abnormalities, usually asymptomatic and often undiagnosed during life, are the main causes in young athletes. Hypertrophic cardiomyopathy and congenital coronary anomalies are the most commonly occurring disorders. Idiopathic concentric left ventricular hypertrophy (non-physiological), arrhythmogenic right ventricular dysplasia and Marfan's syndrome with aortic rupture have also been implicated. Rarer causes include mitral valve prolapse and myocarditis. Coronary atherosclerosis is the major cause in older, and occasionally in younger athletes. Those involved in the medical care of athletes should be aware of the potential causes of sudden death in these groups. Symptomatic athletes should be fully investigated. Screening programmes are probably not justified on a cost effective basis. The causes of sudden and unexpected death in 29 highly conditioned, competitive athletes, ages 13-30 years, are summarized. Sudden death occurred during or just after severe exertion on the athletic field in 22 of the 29 athletes. Structural cardiovascular abnormalities were identified at necropsy in 28 of the 29 athletes (97%), and in 22 (76%) were almost certainly the cause of death. The most common cause of death in this series was hypertrophic cardiomyopathy, which was present in 14 athletes. Other cardiovascular abnormalities that occurred in more than one athlete were anomalous origin of the left coronary artery from the right (anterior) sinus of Valsalva, idiopathic concentric left ventricular hypertrophy, coronary heart disease and ruptured aorta. Cardiac disease was suspected during life in only seven of the 29 patients, and in only two of the seven was the correct diagnosis made clinically. Hence, in this series of young athletes, sudden death was usually due to structural cardiovascular disease, and hypertrophic cardiomyopathy was a frequent cause of sudden death; atherosclerotic coronary heart disease was relatively uncommon. The causes of sudden, unexpected death in highly-conditioned competitive athletes are summarized. In the vast majority of young athletes (less than 35 years of age) sudden death is due to underlying structural cardiovascular disease. Hypertrophic cardiomyopathy appears to be the most common cause of such deaths and may account for about one-half of the sudden deaths in a youthful athletic population. Cardiovascular abnormalities that appear to be less frequent important causes of sudden death include anomalous origin of the left coronary artery from the anterior sinus of Valsalva, ruptured aorta (due to cystic medial necrosis), idiopathic concentric left ventricular hypertrophy and coronary artery atherosclerosis. Other diseases which are probably particularly uncommon causes of sudden death in the young athlete include mitral valve prolapse, aortic valvular stenosis, acute myocarditis, QT interval prolongation syndromes, hypoplasia of the coronary arteries or sarcoidosis. Cardiovascular disease in young athletes is usually unsuspected during life. In only about 25% of those competitive athletes who die suddenly is underlying disease identified prior to participation and rarely is the correct clinical diagnosis made. In contrast, when sudden death occurs in older competitive or recreational athletes (over 35 years of age) it is usually due to coronary artery disease. Hypertrophic cardiomyopathy (HCM) is the most common cause of death in the young, particularly in young competitive athletes. Death often occurs suddenly in asymptomatic, apparently healthy individuals. Several clinical parameters as well as genetic factors have been characterized that can identify those HCM patients who are at high risk for sudden cardiac death (SCD). The clinical parameters that have some predictive values for SCD in HCM patients are the following: a prior history of SCD, a family history of SCD, history of syncope, symptomatic ventricular tachycardia on Holter monitoring, inducible ventricular tachycardia during electrophysiologic studies, and myocardial ischemia in children with HCM. Recent identification of mutations in the beta myosin heavy chain gene and genotype-phenotype correlation in HCM patients have shown that the beta myosin heavy chain mutations are also prognosticators in HCM families. Several mutations such as Arg403Gln and Arg719Gln are associated with a high incidence of SCD, while Leu908Val mutation is associated with a benign course and a low incidence of SCD in HCM families. Additional genetic factors such as a polymorphism in angiotensin-converting enzyme I gene may also contribute to a high incidence of SCD in HCM families. Identification and characterization of HCM patients at high risk for SCD provide the opportunity to render prophylactic therapeutic interventions, such as implantation of defibrillators, in these individuals. Hypertrophic cardiomyopathy (HC) is probably the most common cause of sudden cardiac death in youthful athletes, and this diagnosis has represented a contraindication to continued participation in competitive sports. Less well appreciated is the fact that within the clinical spectrum of HC are patients who, despite having this disease, have been able to undertake particularly intensive and often extraordinary levels of training for sports competition over many years without dying suddenly. Fourteen such patients (13 men and 1 woman, aged 30 to 66 years [mean 43]) form the present study group. HC was initially identified at 24 to 57 years of age (mean 34), usually under fortuitous circumstances. Patients most often competed in distance running (including the marathon, 7), but also in swimming, triathalon, basketball, and football. The duration of training ranged from 6 to 22 years (mean 15) and 5 continue to train and compete actively. The magnitude of training, competition, and achievement was considerable in most patients; 12 of the 14 performed either at the national, collegiate or professional level in their sport, completed numerous marathon and triathalon events, or sustained particularly rigorous training regimens of > or = 50 miles/week. Echocardiographic studies demonstrated a left ventricular wall thickness of 18 to 28 mm (mean 20) in most patients (12 of 14) having a relatively localized pattern of ventricular septal hypertrophy. It is possible for some patients with HC to tolerate particularly intense athletic training and competition for many years, and even maintain high levels of achievement without incurring symptoms and disease progression or dying suddenly.(ABSTRACT TRUNCATED AT 250 WORDS) OBJECTIVE: To develop clinical, demographic, and pathological profiles of young competitive athletes who died suddenly. DESIGN: Systematic evaluation of clinical information and circumstances associated with sudden deaths; interviews with family members, witnesses, and coaches; and analyses of postmortem anatomic, microscopic, and toxicologic data. PARTICIPANTS AND SETTING: A total of 158 sudden deaths that occurred in trained athletes throughout the United States from 1985 through 1995 were analyzed. MAIN OUTCOME MEASURES--Characteristics and probable cause of death. RESULTS: Of 158 sudden deaths among athletes, 24 (15%) were explained by noncardiovascular causes. Among the 134 athletes who had cardiovascular causes of sudden death, the median age was 17 years (range, 12-40 years), 120 (90%) were male, 70 (52%) were white, and 59 (44%) were black. The most common competitive sports involved were basketball (47 cases) and football (45 cases), together accounting for 68% of sudden deaths. A total of 121 athletes (90%) collapsed during or immediately after a training session (78 cases) or a formal athletic contest (43 cases), with 80 deaths (63%) occurring between 3 PM and 9 PM. The most common structural cardiovascular diseases identified at autopsy as the primary cause of death were hypertrophic cardiomyopathy (48 athletes [36%]), which was disproportionately prevalent in black athletes compared with white athletes (48% vs 26% of deaths; P = .01), and malformations involving anomalous coronary artery origin (17 athletes [13%]). Of 115 athletes who had a standard preparticipation medical evaluation, only 4 (3%) were suspected of having cardiovascular disease, and the cardiovascular abnormality responsible for sudden death was correctly identified in only 1 athlete (0.9%). CONCLUSIONS: Sudden death in young competitive athletes usually is precipitated by physical activity and may be due to a heterogeneous spectrum of cardiovascular disease, most commonly hypertrophic cardiomyopathy. Preparticipation screening appeared to be of limited value in identification of underlying cardiovascular abnormalities. Nontraumatic sudden death in young athletes is always disturbing, as apparently invincible athletes, become, without warning, victims of silent heart disease. Despite public perception to the contrary, sudden death in young athletes is exceedingly rare. It most commonly occurs in male athletes, who have estimated death rates nearly fivefold greater than the rates of female athletes. Congenital cardiovascular disease is the leading cause of non-traumatic sudden athletic death, with hypertrophic cardiomyopathy being the most common cause. Screening athletes for disorders capable of provoking sudden death is a challenge because of the low prevalence of disease, and the cost and limitations of available screening tests. Current recommendations for cardiovascular screening call for a careful history and physical examination performed by a knowledgeable health care provider. Specialized testing is recommended only in cases that warrant further evaluation. The athlete projects the ultimate image of well-being in the health status spectrum. Nevertheless, exercise-related sudden cardiac death (SCD) is an uncommon, yet tragic, occurrence. Exercise-related SCD is defined by symptoms that arise within 1 hour of participation in sport. The major mechanisms involved in exercise-related SCD are related to haemodynamic and electrophysiological changes brought about by exercise in the susceptible individual. Fatal arrhythmia seems to be the most common mechanism of death. Between 1 and 5 cases of SCD per 1 million athletes occur annually. In young athletes (<35 years old), the majority of these cases are caused by defined and hereditary cardiovascular disorders. Among other aetiologies, hypertrophic cardiomyopathy and coronary artery anomalies are most common in this group. In older athletes (>35 years old), sudden death is usually associated with atherosclerotic cardiac disease. A problem for identifying athletes at risk for SCD is that the athlete's heart undergoes adaptive changes in response to regular physical exercise. Alterations in cardiac function influence the physical examination, the electrocardiogram and the echocardiogram. Because of these characteristic 'abnormalities' of the athlete's heart, it is often difficult to distinguish physiological adaptations from pathophysiological processes. Although studies and observations have helped to clarify the cardiovascular pathology responsible for SCD in young, apparently healthy individuals, effective methods for preventing SCD and identifying and screening athletes at risk remain elusive. Problems with routine comprehensive screening of athletes include the limitations inherent in the predictive value of available diagnostic procedures and the cost of testing large populations. The variation from normal cardiac physiology found within the athletic population and the rarity of SCD in athletes means that elaborate screening to determine individuals at risk is neither practical nor cost effective. A thorough assessment of pertinent family and medical histories, cardiac auscultation of young athletes, evaluation of exercise-induced symptoms and education of older athletes to the symptoms of cardiac ischaemia are all essential to primary prevention of SCD in the athletic population. Until reliable methods can accurately identify those athletes at risk for SCD, broad recommendations are available to help guide the management and participation in sports of athletes with cardiovascular disease. Sudden cardiac death in athletes is usually due to underlying cardiovascular disease. In the young less than 30 years of age, the most common abnormality is hypertrophic cardiomyopathy, followed by congenital coronary artery anomalies. The final common pathway is usually ventricular fibrillation. Sudden cardiac death in the young is rare but remains a source of concern. A careful screening history and physical examination, especially for potential athletes, should identify the majority of young people at risk. Sudden cardiac death of a young competitive athlete is a rare but tragic event. Hypertrophic cardiomyopathy and coronary artery anomalies are the most frequent causes. Most cardiovascular abnormalities go unrecognized until the time of death owing to the lack of preceding signs or symptoms suggestive of disease. Physicians responsible for the care of athletes should be familiar with the various causes of sudden cardiac death, the physiologic adaptations seen in so-called athlete's heart, and existing cardiovascular screening guidelines. The preparticipation evaluation, although it has limitations, is the major instrument readily available for prevention of sudden cardiac death. Effort should be made to follow established consensus guidelines. CONTEXT: Throughout the past 40 years, a vast and sometimes contradictory literature has accumulated regarding hypertrophic cardiomyopathy (HCM), a genetic cardiac disease caused by a variety of mutations in genes encoding sarcomeric proteins and characterized by a broad and expanding clinical spectrum. OBJECTIVES: To clarify and summarize the relevant clinical issues and to profile rapidly evolving concepts regarding HCM. DATA SOURCES: Systematic analysis of the relevant HCM literature, accessed through MEDLINE (1966-2000), bibliographies, and interactions with investigators. STUDY SELECTION AND DATA EXTRACTION: Diverse information was assimilated into a rigorous and objective contemporary description of HCM, affording greatest weight to prospective, controlled, and evidence-based studies. DATA SYNTHESIS: Hypertrophic cardiomyopathy is a relatively common genetic cardiac disease (1:500 in the general population) that is heterogeneous with respect to disease-causing mutations, presentation, prognosis, and treatment strategies. Visibility attached to HCM relates largely to its recognition as the most common cause of sudden death in the young (including competitive athletes). Clinical diagnosis is by 2-dimensional echocardiographic identification of otherwise unexplained left ventricular wall thickening in the presence of a nondilated cavity. Overall, HCM confers an annual mortality rate of about 1% and in most patients is compatible with little or no disability and normal life expectancy. Subsets with higher mortality or morbidity are linked to the complications of sudden death, progressive heart failure, and atrial fibrillation with embolic stroke. Treatment strategies depend on appropriate patient selection, including drug treatment for exertional dyspnea (beta-blockers, verapamil, disopyramide) and the septal myotomy-myectomy operation, which is the standard of care for severe refractory symptoms associated with marked outflow obstruction; alcohol septal ablation and pacing are alternatives to surgery for selected patients. High-risk patients may be treated effectively for sudden death prevention with the implantable cardioverter-defibrillator. CONCLUSIONS: Substantial understanding has evolved regarding the epidemiology and clinical course of HCM, as well as novel treatment strategies that may alter its natural history. An appreciation that HCM, although an important cause of death and disability at all ages, does not invariably convey ominous prognosis and is compatible with normal longevity should dictate a large measure of reassurance for many patients. OBJECTIVES: The goal of this study was to determine the impact of race on identification of hypertrophic cardiomyopathy (HCM). BACKGROUND: Sudden death in young competitive athletes is due to a variety of cardiovascular diseases (CVDs) and, most commonly, HCM. These catastrophes have become an important issue for African Americans, although HCM has been previously regarded as rare in this segment of the U.S. population. METHODS: We studied the relationship of race to the prevalence of CVDs causing sudden death in our national athlete registry, and compared these findings with a representative multicenter hospital-based cohort of patients with HCM. RESULTS: Of 584 athlete deaths, 286 were documented to be due to CVD at ages 17 +/- 3 years; 156 (55%) were white, and 120 (42%) were African American. Most were male (90%), and 67% participated in basketball and football. Among the 286 cardiovascular deaths, most were due to HCM (n = 102; 36%) or anomalous coronary artery of wrong sinus origin (n = 37; 13%). Of the athletes who died of HCM, 42 (41%) were white, but 56 (55%) were African American. In contrast, of 1,986 clinically identified HCM patients, only 158 (8%) were African American (p < 0.001). CONCLUSIONS: In this autopsy series, HCM represented a common cause of sudden death in young and previously undiagnosed African American male athletes, in sharp contrast with the infrequent clinical identification of HCM in a hospital-based population (i.e., by seven-fold). This discrepancy suggests that many HCM cases go unrecognized in the African American community, underscoring the need for enhanced clinical recognition of HCM to create the opportunity for preventive measures to be employed in high-risk patients with this complex disease. Sudden cardiac deaths in athletes are usually due to underlying cardiovascular disease. The final pathway is usually ventricular fibrillation following hypertrophic cardiomyopathy and coronary artery anomalies in young persons below the age of 30 years. Sudden cardiac death in young is rare but remains as a source of concern. A postmortem study was conducted to ascertain the cardiac causes of sudden death in persons below the age group 30 years following exercise in games or otherwise. Out of 15 cases in autopsy finding, hypertrophic cardiomyopathy (n=7) was the commonest cause followed by coronary artery anomalies (n=4). Sudden unexpected death is a source of concern and careful screening of history and physical examination for potential athletes should identify majority of people at risk. The annual incidence of sudden cardiac death in young athletes is approximately 1 in 200,000. The most common causes include hypertrophic cardiomyopathy and arrhythmogenic right ventricular dysplasia/cardiomyopathy. These genetic disorders typically manifest in the second decade of life and have the potential for sudden death as the first symptom. Medical care providers must be aware of these disease entities when evaluating patients with seizures, syncope, and/or palpitations. The purpose of this article is to describe their genetics, clinical presentation, and diagnosis. Most cases of sudden cardiac death in young athletes (<35 years) are caused by inherited cardiomyopathies, notably hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. INTRODUCTION: Sudden cardiac death in athletes is a growing problem, despite the huge existing knowledge in medicine and sports. EFFECTS OF VIGOROUS PHYSICAL ACTIVITY: In response to vigorous physical activity, the body undergoes profound morphologic and functional changes. These changes are usually healthy, but sometimes may gravitate to some cardiac diseases. But still, most saudden cardiac deaths are due to previous unknown diseases. CAUSES OF SUDDEN CARDIAC DEATH: The most common cause of sudden cardiac death in athletes is hypertrophic cardiomyopathy. Other reasons are congenital coronary artery anomalies, nivocarditis, dilatative cardiomyopathy, arrhythmogenic cardiomyopathy of the right ventricle, sarcoidosis, mitral valve prolapse, aortic valve stenosis, atherosclerosis, long QT syndrome, and blunt impact to the chest. CONCLUSION: Bearing in mind the above mentioned, more frequent physical examinations of athletes are recommended. Cardiovascular disease is the most frequent cause of death in young athletes, and hypertrophic cardiomyopathy (HCM) is the single most common condition responsible for these tragedies. Detection of diseases such as HCM can be achieved in general athlete populations through preparticipation screening, and most effectively if testing with electrocardiography or echocardiography is incorporated into the process. Criteria for disqualification and eligibility, based on identified cardiovascular abnormalities, are available in consensus panel guidelines for both United States and European athletes. Removal from intense training and competition is recommended for athletes with HCM, some of whom may ultimately be judged to be at unacceptably high risk for sudden death and eligible for prophylactic defibrillator implantation. Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death in young people, including trained athletes. The implantable cardioverter-defibrillator (ICD), although initially designed as a treatment for older patients with coronary artery disease, has more recently proved to be a safe and effective therapeutic intervention in young patients with HCM, both for primary or secondary prevention of sudden death. The largest such report of >500 patients showed that the ICD intervened appropriately to abort ventricular tachycardia/fibrillation (VT/VF) in 20% of patients over an average follow-up period of only 3.7 years, at a rate of about 4% per year in those patients implanted prophylactically, and often with considerable delays of up to 10 years. Extensive experience with high-risk HCM patients showed that appropriate device discharges for VT/VF occur with similar frequency in patients with 1, 2, or > or = 3 noninvasive risk markers. Despite the extreme morphology characteristic of HCM, often with massive degrees of left ventricular (LV) hypertrophy and/or LV outflow tract obstruction, ICDs performed in a highly effective fashion, with failure to convert life-threatening arrhythmias extraordinarily rare. In conclusion, in a large high-risk HCM cohort, ICD interventions for life-threatening ventricular tachyarrhythmias were frequent and highly effective in restoring normal rhythm. An important proportion of ICD discharges occurred in primary prevention patients with only one risk factor. Therefore, a single marker of high risk may represent sufficient evidence to justify the recommendation for a prophylactic ICD in selected patients with HCM. Hypertrophic cardiomyopathy is considered a principal cause of sudden unexpected cardiac death in young athletes. However, a number of demographic features observed in these deaths are not consistent with the diagnosis. All of these characteristics instead share in common a propensity for ventricular hypertrophy, implying that these deaths may reflect electrical stability in the extremely rare athlete with exaggerated myocardial hypertrophy in response to sports training. This review provides an evidence-based line of reasoning that supports this concept. Hypertrophic cardiomyopathy (HCM) is the main cause of sudden unexpected death in the young and especially in young athletes with an incidence up to 2.3 per 100,000 athletes and year. Risk stratification models including patient history (syncope, familial risk of sudden death) and findings in noninvasive tests (nonsustained ventricular tachycardia, abnormal blood pressure response during exercise, maximum left ventricular wall thickness > or = 30 mm) have been developed in order to estimate the risk of individual patients. Echocardiographic parameters are helpful in distinguishing HCM from athlete's heart. Definitive diagnosis of HCM implicates disqualification from competitive sports resulting in a significant reduction of sudden cardiac death due to HCM during sports competition. This positive development should lead to a widespread preparticipation screening of athletes including historical, clinical, and electrocardiographic examination. At least in borderline findings and symptomatic athletes, an additional echocardiogram should be performed in order to minimize or better exclude the risk of sudden cardiac death. Hypertrophic cardiomyopathy is regarded as the most common cause of sudden cardiac death in young people (including trained athletes). Introduction of implantable cardioverter-defibrillators to the hypertrophic cardiomyopathy patient population represents a new paradigm for clinical practice and perhaps the most significant advance in the management of this disease to date. Implantable defibrillators offer the only proven protection against sudden death by virtue of effectively terminating ventricular tachycardia/fibrillation and, in the process, altering the natural history of hypertrophic cardiomyopathy and providing the potential opportunity of normal or near-normal longevity for many patients. However, targeting the most appropriate candidates for prophylactic device therapy can be complex, compounded by the unpredictability of the underlying arrhythmogenic substrate, absence of a single domit and quantitative risk marker in this heterogeneous disease, and the historical difficulty in assembling sufficiently powered prospective and randomized trials in large patient populations. Nevertheless, the current risk factor algorithm, when combined with a measure of individual physician judgment, is an effective strategy for identifying high-risk patients. Indeed, prevention of sudden death has now become an integral, albeit challenging, component of overall hypertrophic cardiomyopathy management. Hypertrophic cardiomyopathy (HCM) is a common genetic cardiovascular disease that affects the left ventricle. HCM can appear at any age, with the majority of the patients remaining clinically stable. When patients complain of symptoms, these include: dyspnea, dizziness, syncope and angina. HCM can lead to sudden cardiac death (SCD), mainly due to ventricular tachyarrhythmia or ventricular tachycardia. High-risk patients benefit from implantable cardioverter-defibrillators. Left ventricular outflow tract obstruction is not a rare feature in HCM, especially in symptomatic patients, and procedures that abolish that obstruction provide positive and consistent results that can improve long-term survival. HCM is the most common cause of sudden death in young competitive athletes and preparticipation screening programs have to be implemented to avoid these tragic fatalities. The structure of these programs is a matter of large debate. Worldwide registries are necessary to identify the full extent of HCM-related SCD. Sudden death in the young is rare. About 25% of cases occur during sports. Most young people with sudden cardiac death (SCD) have underlying heart disease, with hypertrophic cardiomyopathy and coronary artery anomalies being commonest in most series. Arrhythmogenic right ventricular dysplasia and long QT syndrome are the most common primary arrhythmic causes of SCD. It is estimated that early cardiopulmonary resuscitation and widespread availability of automatic external defibrillators could prevent about a quarter of pediatric sudden deaths. PURPOSE OF REVIEW: This article will review the incidence and most common causes of sudden cardiac death (SCD) in healthy young adults, including competitive athletes, as well as members of the general population. RECENT FINDINGS: SCD is rare but devastating in a young individual. The incidence of SCD in the young ranges from as low as 0.4 per 100,000 patient-years to as high as 13.4 per 100,000 patient-years. SCD occurs in all populations, not only in athletes. SUMMARY: Whether SCD is more common in athletes is the cause of continued debate stemming from conflicting data. Hypertrophic cardiomyopathy is the most common underlying cause of SCD in young athletes in most series; however, in nonathletic populations, the underlying causes of SCD are more varied. Sudden cardiac death (SCD) is an uncommon but devastating potential consequence of participation in competitive sport. It is seen in adolescent and young adult athletes. The most common cause of this, hypertrophic cardiomyopathy (HCM), is a genetic disorder responsible for more than a third of cases and is manageable. Screening is undertaken for HCM, using differing strategies in Europe and North America. Screening and early diagnosis have reduced the mortality rate but has come at a significant economic cost. The evidence and relevant arguments for and against screening are presented together with management strategies as reflected by an illustrative case. Hypertrophic cardiomyopathy is a common inherited cardiovascular disease present in one in 500 of the general population. It is caused by more than 1400 mutations in 11 or more genes encoding proteins of the cardiac sarcomere. Although hypertrophic cardiomyopathy is the most frequent cause of sudden death in young people (including trained athletes), and can lead to functional disability from heart failure and stroke, the majority of affected individuals probably remain undiagnosed and many do not experience greatly reduced life expectancy or substantial symptoms. Clinical diagnosis is based on otherwise unexplained left-ventricular hypertrophy identified by echocardiography or cardiovascular MRI. While presenting with a heterogeneous clinical profile and complex pathophysiology, effective treatment strategies are available, including implantable defibrillators to prevent sudden death, drugs and surgical myectomy (or, alternatively, alcohol septal ablation) for relief of outflow obstruction and symptoms of heart failure, and pharmacological strategies (and possibly radiofrequency ablation) to control atrial fibrillation and prevent embolic stroke. A subgroup of patients with genetic mutations but without left-ventricular hypertrophy has emerged, with unresolved natural history. Now, after more than 50 years, hypertrophic cardiomyopathy has been transformed from a rare and largely untreatable disorder to a common genetic disease with management strategies that permit realistic aspirations for restored quality of life and advanced longevity. The authors hypothesized that prospective, systematic Internet searches could identify occurrences of sudden cardiac death (SCD) in athletes and would be useful for establishing a system of active surveillance. Weekly advanced Google searches of the Internet were conducted for cases of SCD in young athletes during a 12-month period (2007-2008). Athletes ages 11-30 years who collapsed during a game, practice, or within an hour of exercise were included in the study. Individuals with known histories of cardiac issues and events occurring outside the United States were excluded. Verification of SCD was by autopsy reports and death certificates from county coroner offices and vital record agencies. Initially, 71 events were identified. Verification for the cause of death by coroner reports was possible in 45 cases, 43 (96 %) of which were confirmed to be SCDs. A total of 69 individuals 11-30 years of age (mean 17 ± 5 years) died suddenly of cardiovascular causes while participating in 15 different organized sports and a variety of nonorganized physical activities. The most common cause of death was hypertrophic cardiomyopathy (30 %), followed by coronary artery anomalies (9 %), and myocarditis (9 %). The incidence of athlete SCD, the types of sports involved, and the cardiac causes of death in our study were comparable with those of previous reports. Readily available Internet searches have the potential to be a powerful tool for identifying occurrences of athlete SCD. An active surveillance system using Google searches followed by coroner report verification can provide important epidemiologic and clinical information.

Could the Menzerath-Altmann law be proved mathematically trivial in genomes?

Yes. The view of Menzerath-Altmann law in genomes, as inevitable, is seriously flawed.

Menzerath's law, the tendency of Z (the mean size of the parts) to decrease as X (the number of parts) increases, is found in language, music and genomes. Recently, it has been argued that the presence of the law in genomes is an inevitable consequence of the fact that Z=Y/X, which would imply that Z scales with X as Z ∼ 1/X. That scaling is a very particular case of Menzerath-Altmann law that has been rejected by means of a correlation test between X and Y in genomes, being X the number of chromosomes of a species, Y its genome size in bases and Z the mean chromosome size. Here we review the statistical foundations of that test and consider three non-parametric tests based upon different correlation metrics and one parametric test to evaluate if Z ∼ 1/X in genomes. The most powerful test is a new non-parametric one based upon the correlation ratio, which is able to reject Z ∼ 1/X in nine out of 11 taxonomic groups and detect a borderline group. Rather than a fact, Z ∼ 1/X is a baseline that real genomes do not meet. The view of Menzerath-Altmann law as inevitable is seriously flawed.

What is the rate of survival after commotio cordis?

Survival rates for commotio cordis are low, even when resuscitation is performed. Survival rates vary between 10% and 28%.

Commotio cordis is the condition of sudden cardiac death or near sudden cardiac death after blunt, low-impact chest wall trauma in the absence of structural cardiac abnormality. Ventricular fibrillation is the most commonly reported induced arrhythmia in commotio cordis. Blunt impact injury to the chest with a baseball is the most common mechanism. Survival rates for commotio cordis are low, even with prompt CPR and defibrillation. CONTEXT: Although blunt, nonpenetrating chest blows causing sudden cardiac death (commotio cordis) are often associated with competitive sports, dangers implicit in such blows can extend into many other life activities. OBJECTIVE: To describe the comprehensive spectrum of commotio cordis events. DESIGN AND SETTING: Analysis of confirmed cases from the general community assembled in the US Commotio Cordis Registry occurring up to September 1, 2001. MAIN OUTCOME MEASURE: Commotio cordis event. RESULTS: Of 128 confirmed cases, 122 (95%) were in males and the mean (SD) age was 13.6 (8.2) years (median, 14 years; range, 3 months to 45 years); only 28 (22%) cases were aged 18 years or older. Commotio cordis events occurred most commonly during organized sporting events (79 [62%]), such as baseball, but 49 (38%) occurred as part of daily routine and recreational activities. Fatal blows were inflicted with a wide range of velocities but often occurred inadvertently and under circumstances not usually associated with risk for sudden death in informal settings near the home or playground. Twenty-two (28%) participants were wearing commercially available chest barriers, including 7 in whom the projectile made direct contact with protective padding (baseball catchers and lacrosse/hockey goalies), and 2 in whom the projectile was a baseball specifically designed to reduce risk. Only 21 (16%) individuals survived their event, with particularly prompt cardiopulmonary resuscitation/defibrillation (most commonly reversing ventricular fibrillation) the only identifiable factor associated with a favorable outcome. CONCLUSIONS: The expanded spectrum of commotio cordis illustrates the potential dangers implicit in striking the chest, regardless of the intent or force of the blow. These findings also suggest that the safety of young athletes will be enhanced by developing more effective preventive strategies (such as chest wall barriers) to achieve protection from ventricular fibrillation following precordial blows. Commotio cordis is arrhythmia or sudden death from low-impact, blunt trauma to the chest without apparent heart injury. Ventricular fibrillation is the most common associated arrhythmia, and heart block, bundle branch block, and ST-segment elevation are also seen. Commotio cordis occurs most commonly in baseball but has also been reported in hockey, softball, and several other sports. Approximately two to four cases are reported each year, but the true incidence is uncertain. Survival is low, even when resuscitation is performed. Preventive measures include education of participants and coaches, chest protection, and softer baseballs. Other considerations include having external automatic defibrillators and trained personnel at youth sporting events. BACKGROUND: The commotio cordis literature has largely focused on events occurring in the United States. However, with enhanced public awareness, commotio cordis has been increasingly recognized internationally as a cause of cardiac arrest and sudden death due to blunt nonpenetrating chest blows. OBJECTIVE: This study sought to characterize the demographics of commotio cordis globally in comparison to the U.S. experience. METHODS: This study used interrogation of the Commotio Cordis Registry (Minneapolis, Minnesota). RESULTS: We report 60 cases of commotio cordis occurring outside the United States from 19 countries (most commonly the United Kingdom and Canada) on 5 continents and compared these events to 2:3 occuring in the U.S. In the 2 groups, events were largely similar demographically, including frequency of survival (26% in U.S. vs 25%; P = .84), and the striking male predomice evident in both groups (i.e., 95%), although non-U.S. victims were somewhat older (19 ± 13 vs 15 ± 9; P = .002). Not unexpectedly, the groups differed with baseball/softball and football predomit in the United States (55% of events) and soccer, cricket, and hockey most common internationally (47% of events). Notably, the frequency with which soccer participation caused commotio cordis was much more common than expected, particularly in non-U.S. athletes (20% vs 3% U.S.; P < .001). CONCLUSION: Commotio cordis demonstrates a global occurrence, very similar demographically in the United States and internationally. However, the frequency with which chest blows from soccer balls caused commotio cordis events (particularly during sports played internationally) seems to contradict the prevailing notion that air-filled projectiles convey less risk for ventricular fibrillation than do those with solid cores (e.g., baseball or lacrosse balls). CONTENT: Commotio cordis is blunt, nonpenetrating trauma to the chest resulting in irregular heart rhythm and often leading to sudden death. This article presents the epidemiology, variables leading to commotio cordis, theories on predisposing factors, diagnosis, treatment, treatment outcomes, and return-to-play recommendations. EVIDENCE ACQUISITION: A PubMed (MEDLINE) search for commotio cordis was conducted on July 1, 2008, and it yielded 106 results, of which 26 were used for this review, including experimental models, simulation studies, case analysis studies, case reports, general recommendation, review articles, and editorials. RESULTS: There are more than 190 reported cases of commotio cordis in the United States. Forty-seven percent of reported cases occurred during athletic participation. Commotio cordis is the second-most common cause of sudden cardiac death in athletes. Occurrence of commotio cordis is related to time of impact during the cardiac cycle, direct impact over the heart, the hardness and speed of the projectile, and the ineffectiveness of chest barriers. As a result, the US Consumer Product Safety Commission recommends that softer "safety" baseballs be used for youth baseball. Resuscitation using defibrillation was effective in only 15% of cases. Resuscitation within 3 minutes resulted in a survival rate of 25% (17 of 68 cases). Survival drops to 3% when resuscitation is delayed beyond 3 minutes. Survival of commotio cordis has risen from 10% to 15% since 2001. Reduced ventricular ejection fraction has been identified in some commotio cordis survivors. CONCLUSION: Preventive measures, such as using soft "safety" balls and making automated external defibrillators available at sporting venues, can reduce commotio cordis morbidity and mortality. Chest protector designs can be improved to enhance protection. Return to play is best left to clinical judgment given that data are lacking with regard to susceptibility for reoccurrence. BACKGROUND: Commotio cordis events due to precordial blows triggering ventricular fibrillation are a cause of sudden death (SD) during sports and also daily activities. Despite the absence of structural cardiac abnormalities, these events have been considered predomitly fatal with low survival rates. OBJECTIVE: To determine whether expected mortality rates for commotio cordis have changed over time, associated with greater public visibility. METHODS: US Commotio Cordis Registry was accessed to tabulate frequency of reported SD or resuscitated cardiac arrest over 4 decades. RESULTS: At their commotio cordis event, 216 study patients were 0.2-51 years old (mean age 15±9 years); 95% were males. Death occurred in 156 individuals (72%), while the other 60 (28%) survived. Proportion of survivors increased steadily with concomitant decrease in fatal events. For the initial years (1970-1993), 6 of 59 cases survived (10%), while during 1994-2012, 54 of 157 (34%) survived (P = .001). The most recent 6 years, survival from commotio cordis was 31 of 53 (58%), with survivor and nonsurvivor curves ultimately crossing. Higher survival rates were associated with more prompt resuscitation (40%<3 minutes vs 5%>3 minutes; P<.001) and participation in competitive sports (39%; P<.001), but with lower rates in African Americans (1 of 24; 4%) than in whites (54 of 166; 33%; P = .004). Independent predictors of mortality were black race (P = .045) and participation in noncompetitive sports (P = .002), with an on-site automated external defibrillator use protective against SD (P = .01). CONCLUSIONS: Survival from commotio cordis has increased, likely owing to more rapid response times and access to defibrillation, as well as greater public awareness of this condition.

What is the oldest human sample analysed by paleontology proteomics?

The Tyrolean Iceman's brain is the oldest (5300 years old) human sample that has been studied by paleoproteomics.

The application of high-resolution analytical techniques to characterize ancient bone proteins requires clean, efficient extraction to obtain high quality data. Here, we evaluated many different protocols from the literature on ostrich cortical bone and moa cortical bone to evaluate their yield and relative purity using the identification of antibody-antigen complexes on enzyme-linked immunosorbent assay and gel electrophoresis. Moa bone provided an ancient comparison for the effectiveness of bone extraction protocols tested on ostrich bone. For the immunological part of this study, we focused on collagen I, osteocalcin, and hemoglobin because collagen and osteocalcin are the most abundant proteins in the mineralized extracellular matrix and hemoglobin is common in the vasculature. Most of these procedures demineralize the bone first, and then the remaining organics are chemically extracted. We found that the use of hydrochloric acid, rather than ethylenediaminetetraacetic acid, for demineralization resulted in the cleanest extractions because the acid was easily removed. In contrast, the use of ethylenediaminetetraacetic acid resulted in smearing upon electrophoretic separation, possibly indicating these samples were not as pure. The denaturing agents sodium dodecyl sulfate, urea, and guanidine HCl have been used extensively for the solubilization of proteins in non-biomineralized tissue, but only the latter has been used on bone. We show that all three denaturing agents are effective for extracting bone proteins. One additional method tested uses ammonium bicarbonate as a solubilizing buffer that is more appropriate for post-extraction analyses (e.g., proteomics) by removing the need for desalting. We found that both guanidine HCl and ammonium bicarbonate were effective for extracting many bone proteins, resulting in similar electrophoretic patterns. With the increasing use of proteomics, a new generation of scientists are now interested in the study of proteins from not only extant bone but also from ancient bone. Disease detection in historical samples currently relies on DNA extraction and amplification, or immunoassays. These techniques only establish pathogen presence rather than active disease. We report the first use of shotgun proteomics to detect the protein expression profile of buccal swabs and cloth samples from two 500-year-old Andean mummies. The profile of one of the mummies is consistent with immune system response to severe pulmonary bacterial infection at the time of death. Presence of a probably pathogenic Mycobacterium sp. in one buccal swab was confirmed by DNA amplification, sequencing, and phylogenetic analyses. Our study provides positive evidence of active pathogenic infection in an ancient sample for the first time. The protocol introduced here is less susceptible to contamination than DNA-based or immunoassay-based studies. In scarce forensic samples, shotgun proteomics narrows the range of pathogens to detect using DNA assays, reducing cost. This analytical technique can be broadly applied for detecting infection in ancient samples to answer questions on the historical ecology of specific pathogens, as well as in medico-legal cases when active pathogenic infection is suspected. The Tyrolean Iceman, a Copper-age ice mummy, is one of the best-studied human individuals. While the genome of the Iceman has largely been decoded, tissue-specific proteomes have not yet been investigated. We studied the proteome of two distinct brain samples using gel-based and liquid chromatography-mass spectrometry-based proteomics technologies together with a multiple-databases and -search algorithms-driven data-analysis approach. Thereby, we identified a total of 502 different proteins. Of these, 41 proteins are known to be highly abundant in brain tissue and 9 are even specifically expressed in the brain. Furthermore, we found 10 proteins related to blood and coagulation. An enrichment analysis revealed a significant accumulation of proteins related to stress response and wound healing. Together with atomic force microscope scans, indicating clustered blood cells, our data reopens former discussions about a possible injury of the Iceman's head near the site where the tissue samples have been extracted.

What are the results of loss of the protein Lon1 in the plant Arabidopsis?

Loss of Lon1 in Arabidopsis changes the mitochondrial proteome leading to altered metabolite profiles and growth retardation. Additionaly, seedling establishment is also impaired.

Maintece of protein quality control and turnover is essential for cellular homeostasis. In plant organelles this biological process is predomitly performed by ATP-dependent proteases. Here, a genetic screen was performed that led to the identification of Arabidopsis thaliana Lon1 protease mutants that exhibit a post-embryonic growth retardation phenotype. Translational fusion to yellow fluorescent protein revealed AtLon1 subcellular localization in plant mitochondria, and the AtLon1 gene could complement the respiratory-deficient phenotype of the yeast PIM1 gene homolog. AtLon1 is highly expressed in rapidly growing plant organs of embryonic origin, including cotyledons and primary roots, and in inflorescences, which have increased mitochondria numbers per cell to fulfill their high energy requirements. In lon1 mutants, the expression of both mitochondrial and nuclear genes encoding respiratory proteins was normal. However, mitochondria isolated from lon1 mutants had a lower capacity for respiration of succinate and cytochrome c via complexes II and IV, respectively. Furthermore, the activity of key enzymes of the tricarboxylic acid (TCA) cycle was significantly reduced. Additionally, mitochondria in lon1 mutants had an aberrant morphology. These results shed light on the developmental mechanisms of selective proteolysis in plant mitochondria and suggest a critical role for AtLon1 protease in organelle biogenesis and seedling establishment. Intracellular selective proteolysis is an important post-translational regulatory mechanism maintaining protein quality control by removing defective, damaged or even deleterious protein aggregates. The ATP-dependent Lon protease is a key component of protein quality control that is highly conserved across the kingdoms of living organisms. Major advancements have been made in bacteria and in non-plant organisms to understand the role of Lon in protection against protein oxidation, ageing and neurodegenerative diseases. This review presents the progress currently made in plants. The Lon gene family in Arabidopsis consists of four members that produce distinct protein isoforms localized in several organelles. Lon1 and Lon4 that potentially originate from a recent gene duplication event are dual-targeted to mitochondria and chloroplasts through distinct mechanisms revealing divergent evolution. Arabidopsis mutant analysis showed that mitochondria and peroxisomes biogenesis or maintece of function is modulated by Lon1 and Lon2, respectively. Consequently, the lack of Lon selective proteolysis leading to growth retardation and impaired seedling establishment can be attributed to defects in the oil reserve mobilization pathway. The current progress in Arabidopsis research uncovers the role of Lon in the proteome homeostasis of plant organelles and stimulates biotechnology scenarios of plant tolerance against harsh abiotic conditions because of climate instability. Lon1 is an ATP-dependent protease and chaperone located in the mitochondrial matrix in plants. Knockout in Arabidopsis (Arabidopsis thaliana) leads to a significant growth rate deficit in both roots and shoots and lowered activity of specific mitochondrial enzymes associated with respiratory metabolism. Analysis of the mitochondrial proteomes of two lon1 mutant alleles (lon1-1 and lon1-2) with different severities of phenotypes shows a common accumulation of several stress marker chaperones and lowered abundance of Complexes I, IV, and V of OXPHOS. Certain enzymes of the tricarboxylic acid (TCA) cycle are modified or accumulated, and TCA cycle bypasses were repressed rather than induced. While whole tissue respiratory rates were unaltered in roots and shoots, TCA cycle intermediate organic acids were depleted in leaf extracts in the day in lon1-1 and in both lon mutants at night. No significant evidence of broad steady-state oxidative damage to isolated mitochondrial samples could be found, but peptides from several specific proteins were more oxidized and selected functions were more debilitated in lon1-1. Collectively, the evidence suggests that loss of Lon1 significantly modifies respiratory function and plant performance by small but broad alterations in the mitochondrial proteome gained by subtly changing steady-state protein assembly, stability, and damage of a range of components that debilitate an anaplerotic role for mitochondria in cellular carbon metabolism.

Which gene is involved in Giant Axonal Neuropathy?

Giant axonal neuropathy (GAN) is a progressive neurodegenerative disease caused by autosomal recessive mutations in the GAN gene resulting in a loss of a ubiquitously expressed protein, gigaxonin

Giant axonal neuropathy (GAN) is an autosomal recessive neurologic disorder clinically characterized by a severe polyneuropathy, CNS abnormalities, and characteristic tightly curled hair. Recently, mutations in the gigaxonin gene have been identified as the underlying genetic defect. The authors report two novel mutations confirming that GAN is caused by mutations in the gigaxonin gene and raise the question whether some mutations may cause a mild subclinical neuropathy. Giant axonal neuropathy is a rare severe autosomal recessive childhood disorder affecting both the peripheral nerves and the central nervous system. Peripheral nerves characteristically show giant axonal swellings filled with neurofilaments. The giant axonal neuropathy gene was localised by homozygosity mapping to chromosome 16q24.1 and identified as encoding a novel, ubiquitously expressed cytoskeletal protein named gigaxonin.We describe a consanguineous Algerian family with three affected sibs aged 16, 14 and 12 years who present a mild demyelinating sensory motor neuropathy, hypoacousia and kyphoscoliosis which was moderate in the two elder patients, severe in the third one, with no sign of central nervous system involvement and normal cerebral magnetic resoce imaging. This clinical picture is different from the classical severe form, with kinky hairs and early onset of central nervous system involvement and from the less severe form, with protracted course and late involvement of central nervous system. Nerve biopsy showed a moderate loss of myelinated fibers and several giant axons with thin or absent myelin, filled with neurofilaments. This neuropathological aspect is similar to the previously described families linked to the gigaxonin gene. Genetic study in this family showed absence of linkage to chromosome 16q24.1, indicating for the first time, a genetic heterogeneity in giant axonal neuropathy. We propose to call this form of giant axonal neuropathy giant axonal neuropathy 2, and to use the name of giant axonal neuropathy 1 for the form linked to 16q24.1. Giant axonal neuropathy (GAN, MIM: 256850) is a devastating autosomal recessive disorder characterized by an early onset severe peripheral neuropathy, varying central nervous system involvement and strikingly frizzly hair. Giant axonal neuropathy is usually caused by mutations in the gigaxonin gene (GAN) but genetic heterogeneity has been demonstrated for a milder variant of this disease. Here, we report ten patients referred to us for molecular genetic diagnosis. All patients had typical clinical signs suggestive of giant axonal neuropathy. In seven affected individuals, we found disease causing mutations in the gigaxonin gene affecting both alleles: two splice-site and four missense mutations, not reported previously. Gigaxonin binds N-terminally to ubiquitin activating enzyme E1 and C-terminally to various microtubule associated proteins causing their ubiquitin mediated degradation. It was shown for a number of gigaxonin mutations that they impede this process leading to accumulation of microtubule associated proteins and there by impairing cellular functions. The objective of the study was to investigate a girl with giant axonal neuropathy and detect the mutation of GAN gene in her family. The encoding exons of GAN gene were amplified from genomic DNA of the proband and her parents by polymerase chain reaction and directly sequenced after purification. The proband manifested typical neurological symptoms and pathological abnormalities. The case had 2 heterozygous missense mutations in GAN gene: 1. c. 224 T>A in exon 2, her mother was a heterozygote of this mutation and had normal phenotype; 2. c.1634G>A in exon 10, and her father was a heterozygote of this mutation and had normal phenotype. Both of the mutations caused amino acid changes in the gigaxonin protein. In this family, missense mutation of c.224 T>A and missense mutation of c.1634G>A in GAN gene caused the phenotype of giant axonal neuropathy in the proband. Her parents are heterozygotes of the disease without symptoms. Giant axonal neuropathy is a rare autosomal recessive disorder, which typically involves both central and peripheral nervous system. Yet the phenotypic-genotypic correlation remains obscure. We report a novel compound heterozygous mutation with the c. 805C>T in exon 4(Arg545His missense mutation) and the c. 1634G>A in exon 11(Arg269Trp missense mutation) in an 11-year-old Chinese giant axonal neuropathy case. This patient had an atypical giant axonal neuropathy phenotype rather similar to Charcot-Marie-Tooth disease, without tightly curled hair and mental retardation. The patient had a slowly progressive sensory motor neuropathy since age 3 years, and she also had nystagmus, feet deformities, scoliosis, and cerebellar tonsillar protrusion. Electrophysiological studies indicated a predomitly axonal sensory-motor neuropathy. The diagnosis was confirmed by sural nerve biopsy and direct sequencing of all the 11 gigaxonin exons. The proband's parents are heterozygotes of the disease without symptoms. Our findings extend the number of gigaxonin mutations that cause giant axonal neuropathy. Giant axonal neuropathy is a severe autosomal recessive neurodegenerative disorder of childhood that affects both the peripheral and central nervous systems. It is caused by mutations in the GAN gene linked to chromosome 16q24.1 At least 45 distinct disease-causing mutations have been identified throughout the gene in families of various ethnic origins, with different symptomatologies and different clinical courses. To date, no characteristic mutation or phenotype-genotype correlation has been established. We describe a novel missense mutation in four siblings born to consanguineous parents of Arab original with clinical and molecular features compatible with giant axonal neuropathy. The phenotype was characterized by a predomit motor and sensory peripheral neuropathies and severe skeletal deformities. Giant Axonal Neuropathy is a pediatric neurodegenerative disorder caused by autosomal recessive mutations in the GAN gene on chromosome 16q24.1. Mutations in the GAN gene lead to functional impairment of the cytoskeletal protein gigaxonin and a generalized disorder of intermediate filaments, including neurofilaments in axons. Tightly curled hair is a common but not universal feature of Giant Axonal Neuropathy. The pathogenesis of curly hair is unknown, although disruption of keratin architecture is thought to play a role. As part of a broader natural history study of Giant Axonal Neuropathy, we found that the absence of curly hair is correlated with superior motor function (p=0.013) when controlling for age, as measured by the Gross Motor Function Measure. Theoretically, higher levels of functional gigaxonin protein or compensatory mechanisms could produce fewer abnormalities of neurofilaments and keratin, accounting for this phenotype. We suggest that straight-haired patients with Giant Axonal Neuropathy are potentially underdiagnosed due to their divergence from the classic phenotype of the disease. Due to their non-specific features of an axonal neuropathy, these patients may be misdiagnosed with Charcot-Marie-Tooth Disease type 2. Genetic testing for Giant Axonal Neuropathy should be considered in relevant cases of Charcot-Marie-Tooth Disease type 2. INTRODUCTION: Giant axonal neuropathy (GAN) is a rare autosomal recessive neurodegenerative disorder caused by mutations in the GAN gene. Herein we report ultrastructural changes in Chinese patients with GAN. METHODS: General clinical assessment, sural nerve biopsy, and genetic analysis were performed. RESULTS: Sural biopsy revealed giant axons in 3 patients, 2 with a mild phenotype and 1 with a classical phenotype. Ultrastructurally, all patients had giant axons filled with closely packed neurofilaments. In addition, the classical patient had some axons containing irregular tubular-like structures. GAN mutation analysis revealed novel compound heterozygous c.98A>C and c.158C>T mutations in the BTB domain in 1 mild patient, a novel homozygous c.371T>G mutation in the BACK domain in another mild patient, and a novel c.1342G>T homozygous mutation in the Kelch domain in the classical patient. CONCLUSION: Closely packed neurofilaments in giant axons are common pathological changes in Chinese patients with GAN, whereas irregular tubular-like structures appear in the classical type of this neuropathy. Giant axonal neuropathy (GAN) is a rare pediatric neurodegenerative disease. It is best known for the "giant" axons caused by accumulations of intermediate filaments. The disease is progressive, with onset around age 3 years and death by the third decade of life. GAN results from recessive mutations in the GAN gene encoding gigaxonin, and our analysis of all reported mutations shows that they are distributed throughout the protein structure. Precisely how these mutations cause the disease remains to be determined. In addition to changes in peripheral nerves that are similar to those seen in neuropathies such as Charcot-Marie-Tooth type 2, GAN patients exhibit a wide range of central nervous system signs. These features, corroborated by degeneration of central tracts apparent from postmortem pathology, indicate that GAN is also a progressive neurodegenerative disease. To reflect this phenotype more precisely, we therefore propose that the disease should be more appropriately referred to as "giant axonal neurodegeneration."

Are there studies representing the involvement of Notch mutations in neurodegenerative diseases such as Down syndrome, Pick's and Prion's disease, and cadasil syndrome?

The Notch signaling pathway is an evolutionarily conserved, intercellular signaling mechanism essential for proper embryonic development in organisms as diverse as insects, nematodes, echinoderms and mammals. Disruptions in conserved developmental pathways frequently result in inherited congenital anomalies in humans. Mutations in genes encoding Notch pathway components underlie human disease such as Down syndrome, Pick's and Prion's disease, and cadasil syndrome.

In addition to neuronal vacuolation and astrocytic hypertrophy, dendritic atrophy is a prominent feature of prion disease. Because increased Notch-1 expression and cleavage releasing its intracellular domain (NICD) inhibit both dendrite growth and maturation, we measured their levels in brains from mice inoculated with Rocky Mountain Laboratory (RML) prions. The level of NICD was elevated in the neocortex, whereas the level of beta-catenin, which stimulates dendritic growth, was unchanged. During the incubation period, levels of the disease-causing prion protein isoform, PrPSc, and NICD increased concomitantly in the neocortex. Additionally, increased levels of Notch-1 mRNA and translocation of NICD to the nucleus correlated well with regressive dendritic changes. In scrapie-infected neuroblastoma (ScN2a) cells, the level of NICD was elevated compared with uninfected control (N2a) cells. Long neurofilament protein-containing processes extended from the surface of N2a cells, whereas ScN2a cells had substantially shorter processes. Transfection of ScN2a cells with a Notch-1 small interfering RNA decreased Notch-1 mRNA levels, diminished NICD concentrations, and rescued the long process phenotype. These results suggest that PrPSc in neurons and in ScN2a cells activates Notch-1 cleavage, resulting in atrophy of dendrites in the CNS and shrinkage of processes on the surface of cultured cells. Whether diminishing Notch-1 activation in vivo can prevent or even reverse neurodegeneration in prion disease remains to be established. Down syndrome (DS) patients suffer from mental retardation, but also display enhanced beta-APP production and develop cortical amyloid plaques at an early age. As beta-APP and Notch are both processed by gamma-secretase, we analyzed expression of the Notch signaling pathway in the adult DS brain and in a model system for DS, human trisomy 21 fibroblasts by quantitative PCR. In adult DS cortex we found that Notch1, Dll1 and Hes1 expression is up-regulated. Moreover, DS fibroblasts and Alzheimer disease cortex also show overexpression of Notch1 and Dll1, indicating that enhanced beta-APP processing found in both DS and AD could be instrumental in these changes. Using pull-down studies we could demonstrate interaction of APP with Notch1, suggesting that these transmembrane proteins form heterodimers, but independent of gamma-secretase. We could demonstrate binding of the intracellular domain of Notch1 to the APP adaptor protein Fe65. Furthermore, activated Notch1 can trans-activate an APP target gene, Kai1, and vice versa, activated APP can trans-activate the classical Notch target gene Hes1. These data suggest that Notch expression is activated in Down syndrome, possibly through cross-talk with APP signaling. This interaction might affect brain development, since the Notch pathway plays a pivotal role in neuron-glia differentiation. Notch-1 is a protein that influences cell fate decisions, with its expression occurring primarily during embryogenesis and development. However, Notch-1 is also expressed in the adult brain, in regions with high synaptic plasticity, particularly the hippocampus. Its role in adults is unknown; however, it may impact neurite outgrowth or cell differentiation in adult brain regions undergoing neurogenesis. Notch-1 is increased in Alzheimer's disease (AD); however, its expression in other CNS degenerative diseases has not been described. To begin to define the range of degenerative disorders where Notch-1 expression is altered, we examined Notch-1 immunoreactivity in a variety of neurodegenerative diseases to determine whether its increase is selective for AD. We examined sections of hippocampus from 13 AD, 13 classical Pick's disease (PiD; with Pick bodies), 4 dementia lacking distinctive histopathology (DLDH) and 8 control brains, emphasizing hippocampal (dentate gyrus) pathology. We determined that Notch-1 immunoexpression is increased in AD and PiD relative to control cases. DLDH cases were not significantly different than control cases with respect to Notch-1 expression. Given the increase in Notch-1 immunoexpression in AD and PiD, two diseases where abnormal tau aggregates are present, and the lack of Notch-1 immunoexpression in DLDH (where tau aggregates are absent), we cannot rule out the possibility that tau aggregates are associated with Notch-1 expression in neurodegenerative diseases. Missense mutations in the PRESENILIN1 (PSEN1) gene frequently underlie familial Alzheimer's disease (FAD). Nonsense and most splicing mutations result in the synthesis of truncated peptides, and it has been assumed that truncated PSEN1 protein is functionless so that heterozygotes for these mutations are unaffected. Some FAD mutations affecting PSEN1 mRNA splicing cause loss of exon 8 or 9 sequences while maintaining the reading frame. We attempted to model these exon-loss mutations in zebrafish embryos by injecting morpholino antisense oligonucleotides (morpholinos) directed against splice acceptor sites in zebrafish psen1 transcripts. However, this produced cryptic changes in splicing potentially forming mRNAs encoding truncated presenilin proteins. Aberrant splicing in the region between exons 6 and 8 produces potent domit negative effects on Psen1 protein activity, including Notch signalling, and causes a hydrocephalus phenotype. Reductions in Psen1 activity feedback positively to increase psen1 transcription through a mechanism apparently independent of gamma-secretase. We present evidence that the domit negative effects are mediated through production of truncated Psen1 peptides that interfere with the normal activity of both Psen1 and Psen2. Mutations causing such truncations would be domit lethal in embryo development. Somatic cellular changes in ageing cells that interfere with PSEN1 splicing, or otherwise cause protein truncation, might contribute to sporadic Alzheimer's disease, cancer and other diseases. Stem cells are central to the development and maintece of many tissues. This is due to their capacity for extensive proliferation and differentiation into effector cells. More recently it has been shown that the proliferative and differentiative ability of stem cells decreases with age, suggesting that this may play a role in tissue aging. Down syndrome (DS), is associated with many of the signs of premature tissue aging including T-cell deficiency, increased incidence of early Alzheimer-type, Myelodysplastic-type disease and leukaemia. Previously we have shown that both hematopoietic (HSC) and neural stem cells (NSC) in patients affected by DS showed signs of accelerated aging. In this study we tested the hypothesis that changes in gene expression in HSC and NSC of patients affected by DS reflect changes occurring in stem cells with age. The profiles of genes expressed in HSC and NSC from DS patients highlight pathways associated with cellular aging including a downregulation of DNA repair genes and increases in proapoptotic genes, s-phase cell cycle genes, inflammation and angiogenesis genes. Interestingly, Notch signaling was identified as a potential hub, which when deregulated may drive stem cell aging. These data suggests that DS is a valuable model to study early events in stem cell aging. Prion diseases are disorders of protein conformation in which PrPC, the normal cellular conformer, is converted to an abnormal, protease-resistant conformer rPrPSc. Approximately 80% of rPrPSc accumulates in neuronal plasma membranes where it changes their physical properties and profoundly affects membrane functions. In this review we explain how rPrPSc is transported along axons to presynaptic boutons and how we envision the conversion of PrPC to rPrPSc in the postsynaptic membrane. This information is a prerequisite to the second half of this review in which we present evidence that rPrPSc accumulation in synaptic regions links Notch-1 signaling with the dendritic degeneration. The hypothesis that the Notch-1 intracellular domain, NICD, is involved in prion disease was tested by treating prion-infected mice with the gamma-secretase inhibitor (GSI) LY411575, with quinacrine (Qa), and with the combination of GSI + Qa. Surprisingly, treatment with GSI alone markedly decreased NICD but did not prevent dendritic degeneration. Qa alone produced near normal dendritic trees. The combined GSI + Qa treatment resulted in a richer dendritic tree than in controls. We speculate that treatment with GSI alone inhibited both stimulators and inhibitors of dendritic growth. With the combined GSI + Qa treatment, Qa modulated the effect of GSI perhaps by destabilizing membrane rafts. GSI + Qa decreased PrPSc in the neocortex and the hippocampus by 95%, but only by 50% in the thalamus where disease was begun by intrathalamic inoculation of prions. The results of this study indicate that GSI + Qa work synergistically to prevent dendrite degeneration and to block formation of PrPSc. Cerebral autosomal domit arteriopathy with subcortical infarct and leukoencephalopathy: A rare syndrome raising anesthetic concerns! Anaplastic astrocytoma WHO grade III (A3) is a lethal brain tumor that often occurs in middle aged patients. Clinically, it is challenging to distinguish A3 from glioblastoma multiforme (GBM) WHO grade IV. To reveal the genetic landscape of this tumor type, we sequenced the exome of a cohort of A3s (n=16). For comparison and to illuminate the genomic landscape of other glioma subtypes, we also included in our study diffuse astrocytoma WHO grade II (A2, n=7), oligoastrocytoma WHO grade II (OA2, n=2), anaplastic oligoastrocytoma WHO grade III (OA3, n=4), and GBM (n=28). Exome sequencing of A3s identified frequent mutations in IDH1 (75%, 12/16), ATRX (63%, 10/16), and TP53 (82%, 13/16). In contrast, the majority of GBMs (75%, 21/28) did not contain IDH1 or ATRX mutations, and displayed a distinct spectrum of mutations. Finally, our study also identified novel genes that were not previously linked to this tumor type. In particular, we found mutations in Notch pathway genes (NOTCH1, NOTCH2, NOTCH4, NOTCH2NL), including a recurrent NOTCH1-A465Tmutation, in 31% (5/16) of A3s. This study suggests genetic signatures will be useful for the classification of gliomas. Signaling pathways have become a major source of targets for novel therapies in hepatocellular carcinoma (HCC). Survival benefits achieved with sorafenib, a multikinase inhibitor, are unprecedented and underscore the importance of improving our understanding of how signaling networks interact in transformed cells. Numerous signaling modules are de-regulated in HCC, including some related to growth factor signaling (e.g., IGF, EGF, PDGF, FGF, HGF), cell differentiation (WNT, Hedgehog, Notch), and angiogenesis (VEGF). Intracellular mediators such as RAS and AKT/MTOR may also play a role in HCC development and progression. Different molecular mechanisms have been shown to induce aberrant pathway activation. These include point mutations, chromosomal aberrations, and epigenetically driven down-regulation. The use of novel molecular technologies such as next-generation sequencing in HCC research has enabled the identification of novel pathways previously underexplored in the HCC field, such as chromatin remodeling and autophagy. Considering recent failures of molecular therapies in advanced clinical trials (e.g., sunitinib, brivanib), survey of these and other new pathways may provide alternative therapeutic targets. Cerebral arteriovenous malformations (AVMs) are common vascular malformations, which may result in hemorrhagic strokes and neurological deficits. Bone morphogenetic protein (BMP) and Notch signaling are both involved in the development of cerebral AVMs, but the cross-talk between the two signaling pathways is poorly understood. Here, we show that deficiency of matrix Gla protein (MGP), a BMP inhibitor, causes induction of Notch ligands, dysregulation of endothelial differentiation, and the development of cerebral AVMs in MGP null (Mgp(-/-)) mice. Increased BMP activity due to the lack of MGP induces expression of the activin receptor-like kinase 1, a BMP type I receptor, in cerebrovascular endothelium. Subsequent activation of activin receptor-like kinase 1 enhances expression of Notch ligands Jagged 1 and 2, which increases Notch activity and alters the expression of Ephrin B2 and Ephrin receptor B4, arterial and venous endothelial markers, respectively. Reducing the expression of Jagged 1 and 2 in the Mgp(-/-) mice by crossing them with Jagged 1 or 2 deficient mice reduces Notch activity, normalizes endothelial differentiation, and prevents cerebral AVMs, but not pulmonary or renal AVMs. Our results suggest that Notch signaling mediates and can modulate changes in BMP signaling that lead to cerebral AVMs. BACKGROUND: Alterations in the NOTCH1 signaling pathway are found in about 60% of pediatric T-ALL, but its impact on prognosis remains unclear. PROCEDURE: We extended the previously published CoALL cohort (n = 74) to a larger cohort (n = 127) and additionally included 38 Argentine patients from ALL IC-BFM to potentially identify novel mutations and decipher a stronger discriminatory effect on the genotype/phenotype relationship with regard to early treatment response and long-term outcome. RESULTS: Overall, 101 out of 165 (61.2%) T-ALL samples revealed at least one NOTCH1 mutation, 28 of whom had combined NOTCH1 and FBXW7 mutations. Eight T-ALL samples (4.8%) exclusively revealed FBXW7 mutations. Fifty-six T-ALL (33.9%) exhibited a wild-type configuration of either gene. Four novel NOTCH1 mutations were identified localized in the C-terminal PEST domain, in the rarely affected LNR repeat domain and in the ankyrin domain. Novel LNR mutations may contribute to a better understanding of the structure of the NOTCH1 negative regulatory region (NRR) and the R1946 mutation in the ankyrin domain may represent an unusual loss-of-function mutation. CONCLUSIONS: Overall, NOTCH1 pathway mutations did not affect the relapse rate and outcome of the extended T-ALL cohort uniformly treated according to CoALL protocols, although NOTCH1 mutations were associated with good response to induction therapy (P = 0.009). Individually, HD and PEST domain mutations might exert distinct functional effects on cellular homeostasis under treatment NOTCH1 pathway activity with prognostic implications. The Notch signaling pathway plays a critical role in maintaining the balance between cell proliferation, differentiation and apoptosis, and is a highly conserved signaling pathway that regulates normal development in a context- and dose-dependent manner. Dysregulation of Notch signaling has been suggested to be key events in a variety of hematological maligcies. Notch1 signaling appears to be the central oncogenic trigger in T cell acute lymphoblastic leukemia (T-ALL), in which the majority of human maligcies have acquired mutations that lead to constitutive activation of Notch1 signaling. However, emerging evidence unexpectedly demonstrates that Notch signaling can function as a potent tumor suppressor in other forms of leukemia. This minireview will summarize recent advances related to the roles of activated Notch signaling in human lymphocytic leukemia, myeloid leukemia, stem cells and stromal microenvironment, and we will discuss the perspectives of Notch signaling as a potential therapeutic target as well.

Are there any functional differences between Mfd and its human Cocaine syndrome protein B (CSB) homolog?

Both Cockayne syndrome protein B (CSB) and Mfd are involved in transcription-coupled repair. CSB is the human TCR coupling factor and Mfd is the bacterial TCR coupling factor. However, unlike Mfd, CSB does not act as a helicase nor does it dissociate stalled RNA polymerase II, suggesting a coupling mechanism in humans different from that in prokaryotes. Moreover, Mfd may be functionally distinct from its human CSB homolog in that it does not detectably contribute to the recovery of gene expression or global repair following oxidative damage.

Transcription is coupled to repair in Escherichia coli and in humans. Proteins encoded by the mfd gene in E. coli and by the ERCC6/CSB gene in humans, both of which possess the so-called helicase motifs, are required for the coupling reaction. It has been shown that the Mfd protein is an ATPase but not a helicase and accomplishes coupling, in part, by disrupting the ternary complex of E. coli RNA polymerase stalled at the site of DNA damage. In this study we overproduced the human CSB protein using the baculovirus vector and purified and characterized the recombit protein. CSB has an ATPase activity that is stimulated strongly by DNA; however, it neither acts as a helicase nor does it dissociate stalled RNA polymerase II, suggesting a coupling mechanism in humans different from that in prokaryotes. CSB is a DNA-binding protein, and it also binds to XPA, TFIIH, and the p34 subunit of TFIIE. These interactions are likely to play a role in recruiting repair proteins to ternary complexes formed at damage sites. Transcription-coupled repair (TCR) is a cellular process by which some forms of DNA damage are repaired more rapidly from transcribed strands of active genes than from nontranscribed strands or the overall genome. In humans, the TCR coupling factor, CSB, plays a critical role in restoring transcription following both UV-induced and oxidative DNA damage. It also contributes indirectly to the global repair of some forms of oxidative DNA damage. The Escherichia coli homolog, Mfd, is similarly required for TCR of UV-induced lesions. However, its contribution to the restoration of transcription and to global repair of oxidative damage has not been examined. Here, we report the first direct study of transcriptional recovery following UV-induced and oxidative DNA damage in E. coli. We observed that mutations in mfd or uvrA reduced the rate that transcription recovered following UV-induced damage. In contrast, no difference was detected in the rate of transcription recovery in mfd, uvrA, fpg, nth, or polB dinB umuDC mutants relative to wild-type cells following oxidative damage. mfd mutants were also fully resistant to hydrogen peroxide (H(2)O(2)) and removed oxidative lesions from the genome at rates comparable to wild-type cells. The results demonstrate that Mfd promotes the rapid recovery of gene expression following UV-induced damage in E. coli. In addition, these findings imply that Mfd may be functionally distinct from its human CSB homolog in that it does not detectably contribute to the recovery of gene expression or global repair following oxidative damage.

What is membrane scission?

Membrane scission is the final step in order to complete the budding process, pinching off of the vesicle. To promote membrane scission, dynamin proteins polymerize, wrap around, and constrict the membrane. The scission of biological membranes is facilitated by a variety of protein complexes that bind and manipulate lipid bilayers.

Respiratory syncytial virus is a single-stranded RNA virus in the Paramyxoviridae family that preferentially assembles and buds from the apical surface of polarized epithelial cells, forming filamentous structures that contain both viral proteins and the genomic RNA. Recent studies have described both viral and host factors that are involved in ribonucleoprotein assembly and trafficking of viral proteins to the cell surface. At the cell surface, viral proteins assemble into filaments that probably require interactions between viral proteins, host proteins and the cell membrane. Finally, a membrane scission event must occur to release the free virion. This article will review the recent literature describing the mechanisms that drive respiratory syncytial virus assembly and budding. BACKGROUND: Dynamin 2 (Dyn2) is a ~100kDa GTPase that assembles around the necks of nascent endocytic and Golgi vesicles and catalyzes membrane scission. Mutations in Dyn2 that cause centronuclear myopathy (CNM) have been shown to stabilize Dyn2 polymers against GTP-dependent disassembly in vitro. Precisely timed regulation of assembly and disassembly is believed to be critical for Dyn2 function in membrane vesiculation, and the CNM mutations interfere with this regulation by shifting the equilibrium toward the assembled state. METHODS: In this study we use two fluorescence fluctuation spectroscopy (FFS) approaches to show that a CNM mutant form of Dyn2 also has a greater propensity to self-assemble in the cytosol and on the plasma membrane of living cells. RESULTS: Results obtained using brightness analysis indicate that unassembled wild-type Dyn2 is predomitly tetrameric in the cytosol, although different oligomeric species are observed, depending on the concentration of expressed protein. In contrast, an R369W mutant identified in CNM patients forms higher-order oligomers at concentrations above 1μM. Investigation of Dyn2-R369W by Total Internal Reflection Fluorescence (TIRF) FFS reveals that this mutant forms larger and more stable clathrin-containing structures on the plasma membrane than wild-type Dyn2. CONCLUSIONS AND GENERAL SIGNIFICANCE: These observations may explain defects in membrane trafficking reported in CNM patient cells and in heterologous systems expressing CNM-associated Dyn2 mutants. The multivesicular body (MVB) sorting pathway is a mechanism for delivering transmembrane proteins into the lumen of the lysosome for degradation. ESCRT-III is the final complex in the pathway that assembles on endosomes and executes membrane scission of intraluminal vesicles. In addition, proteins of this complex are involved in other topologically similar processes such as cytokinesis, virus egress and autophagy. Here we show that protein kinase CK2α is involved in the phosphorylation of the ESCRT-III subunits CHMP3 and CHMP2B, as well as of VPS4B/SKD1, an ATPase that mediates ESCRT-III disassembly. This phosphorylation is observed both in vitro and in cells. While we do not observe recruitment of CK2α to endosomes, we demonstrate the localization of CK2α to midbodies during cytokinesis. Phosphomimetic and non-phosphorylatable mutants of ESCRT-III proteins can still bind endosomes and localize to midbodies, indicating that CK2α does not regulate ESCRT-III localization. Finally, we analyzed two cellular functions where CHMP3, CHMP2B and VPS4 are known to be involved, epidermal growth factor degradation and cytokinetic abscission. We demonstrate that the former is impaired by CK2α downregulation whereas the latter is not affected. Taken together, our results indicate that CK2α regulates the function of ESCRT-III proteins in MVB sorting. Author information: (1)Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706 Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706 Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706. (2)Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706. (3)Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706 Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706. (4)Department of Biomolecular Chemistry, School of Medicine and Public Health, Department of Botany, Department of Genetics, Department of Chemistry, Graduate Program in Biophysics, Department of Mathematics, Department of Biochemistry, Institute for Molecular Virology, Howard Hughes Medical Institute, and Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706 [email protected]. Dynamin, the GTPase required for clathrin-mediated endocytosis, is recruited to clathrin-coated pits in two sequential phases. The first is associated with coated pit maturation; the second, with fission of the membrane neck of a coated pit. Using gene-edited cells that express dynamin2-EGFP instead of dynamin2 and live-cell TIRF imaging with single-molecule EGFP sensitivity and high temporal resolution, we detected the arrival of dynamin at coated pits and defined dynamin dimers as the preferred assembly unit. We also used live-cell spinning-disk confocal microscopy calibrated by single-molecule EGFP detection to determine the number of dynamins recruited to the coated pits. A large fraction of budding coated pits recruit between 26 and 40 dynamins (between 1 and 1.5 helical turns of a dynamin collar) during the recruitment phase associated with neck fission; 26 are enough for coated vesicle release in cells partially depleted of dynamin by RNA interference. We discuss how these results restrict models for the mechanism of dynamin-mediated membrane scission. The physical properties of membrane necks are relevant in vesiculation, a process that plays an essential role in cellular physiology. Because the neck's radius is, in general, finite, membrane scission and the consequent pinching off of the vesicle can only occur if it is narrowed to permit the necessary membrane topological reformation. Here we examine, in a simple single phase lipid vesicle, how external forces can promote neck constriction not only by direct compression at the neck but also, counterintuitively, by dilation at remote locations. These results provide a new perspective on the role played by actin polymerization in the process of endocytosis. Mammalian cytokinesis proceeds by constriction of an actomyosin ring and furrow ingression, resulting in the formation of the midbody bridge connecting two daughter cells. At the centre of the midbody resides the Flemming body, a dense proteinaceous ring surrounding the interlocking ends of anti-parallel microtubule arrays. Abscission, the terminal step of cytokinesis, occurs near the Flemming body. A series of broad processes govern abscission: the initiation and stabilisation of the abscission zone, followed by microtubule severing and membrane scission-The latter mediated by the endosomal sorting complex required for transport (ESCRT) proteins. A key goal of cell and developmental biologists is to develop a clear understanding of the mechanisms that underpin abscission, and how the spatiotemporal coordination of these events with previous stages in cell division is accomplished. This article will focus on the function and dynamics of the ESCRT proteins in abscission and will review recent work, which has begun to explore how these complex protein assemblies are regulated by the cell cycle machinery.

How many TAp73 isoforms have been identified in humans?

The TP73 gene, due to the presence of two promoters (P1 and P2) in its 5' flanking region, encodes a fully transcriptionally active domain (TAp73) and the amino terminus deleted (ΔNp73). TAp73 possesses pro-apoptotic properties, while deltaNp73 has anti-apoptotic functions. Alternative 3'-end splicing results in generation of at least seven TAp73 distinctive isoforms ( α, β, γ, etc ).

Inactivation of the tumour suppressor p53 is the most common defect in cancer cells. p53 is a sequence specific transcription factor that is activated in response to various forms of genotoxic stress to induce cell cycle arrest and apoptosis. Induction of p53 is subjected to complex and strict control through several pathways, as it will often determine cellular fate. The p73 protein shares strong structural and functional similarities with p53 such as the potential to activate p53 responsive genes and the ability to induce apoptosis. In addition to alternative splicing at the carboxyl terminus which yields several p73 isoforms, a p73 variant lacking the N-terminal transactivation domain (Delta Np73) was described in mice. In this study, we report the cloning and characterisation of the human Delta Np73 isoforms, their regulation by p53 and their possible role in carcinogenesis. As in mice, human Delta Np73 lacks the transactivation domain and starts with an alternative exon (exon 3'). Its expression is driven by a second promoter located in a genomic region upstream of this exon, supporting the idea of two independently regulated proteins, derived from the same gene. As anticipated, Delta Np73 is capable of regulating TAp73 and p53 function since it is able to block their transactivation activity and their ability to induce apoptosis. Interestingly, expression of the Delta Np73 is strongly up-regulated by the TA isoforms and by p53, thus creating a feedback loop that tightly regulates the function of TAp73 and more importantly of p53. The regulation of Delta Np73 is exerted through a p53 responsive element located on the Delta N promoter. Expression of Delta Np73 not only regulates the function of p53 and TAp73 but also shuts off its own expression, once again finely regulating the whole system. Our data also suggest that increased expression of Delta Np73, functionally inactivating p53, could be involved in tumorogenesis. An extensive analysis of the expression pattern of Delta Np73 in primary tumours would clarify this issue. p73, a recently identified gene highly homologous to p53, can transactivate p53 target genes and induce apoptosis. Here we report the identification of an NH(2)-terminal truncated isoform of human p73, DeltaNp73, which is capable of suppressing p53- and p73-dependent transactivation. We speculate that this suppression is achieved by competing for the DNA binding site in the case of p53 and by direct association in the case of TAp73. Expression of DeltaNp73 in cancer cell lines also inhibited suppressive activity of p53 and TAp73 in colony formation, implying possible involvement of DeltaNp73 in oncogenesis by inhibiting the tumor-suppressive function of p53 and TAp73. Also reported is the identification of TAp73eta, a new member of the COOH-terminal truncated isoform of p73 and tissue-specific expression of these isoforms, along with other previously identified p73 isoforms. The p73 gene is a p53 homologue which induces apoptosis and inhibits cell proliferation. Although p73 maps at 1p36.3 and is frequently deleted in neuroblastoma (NB), it does not act as a classic oncosuppressor gene. In developing sympathetic neurons of mice, p73 is predomitly expressed as a truncated anti-apoptotic isoform (DeltaNp73), which antagonizes both p53 and the full-length p73 protein (TAp73). This suggests that p73 may be part of a complex tumor-control mechanism. To determine the role of DeltaNp73 in NB we analyzed the pattern of expression of this gene in vivo and evaluated the prognostic significance of its expression. Our results indicate that DeltaNp73 expression is associated with reduced apoptosis in a NB tumor tissue. Expression of this variant in NB patients significantly correlates with age at diagnosis and VMA urinary excretion. Moreover it is strongly associated with reduced survival (HR=7.93; P<0.001) and progression-free survival (HR=5.3; P<0.001) and its role in predicting a poorer outcome is independent from age, primary tumor site, stage and MYCN amplification (OS: HR=5.24, P=0.012; PFS: HR=4.36, P=0.005). In conclusion our data seem to indicate that DeltaNp73 is a crucial gene in neuroblastoma pathogenesis. p73 has significant homology to p53. However, tumor-associated up-regulation of p73 and genetic data from human tumors and p73-deficient mice exclude a classical Knudson-type tumor suppressor role. We report that the human TP73 gene generates an NH(2) terminally truncated isoform. DeltaNp73 derives from an alternative promoter in intron 3 and lacks the transactivation domain of full-length TAp73. DeltaNp73 is frequently overexpressed in a variety of human cancers, but not in normal tissues. DeltaNp73 acts as a potent transdomit inhibitor of wild-type p53 and transactivation-competent TAp73. DeltaNp73 efficiently counteracts transactivation function, apoptosis, and growth suppression mediated by wild-type p53 and TAp73, and confers drug resistance to wild-type p53 harboring tumor cells. Conversely, down-regulation of endogenous DeltaNp73 levels by antisense methods alleviates its suppressive action and enhances p53- and TAp73-mediated apoptosis. DeltaNp73 is complexed with wild-type p53, as demonstrated by coimmunoprecipitation from cultured cells and primary tumors. Thus, DeltaNp73 mediates a novel inactivation mechanism of p53 and TAp73 via a domit-negative family network. Deregulated expression of DeltaNp73 can bestow oncogenic activity upon the TP73 gene by functionally inactivating the suppressor action of p53 and TAp73. This trait might be selected for in human cancers. TP73, despite significant homology to TP53, is not a classic tumor suppressor gene, since it exhibits upregulation of nonmutated products in human tumors and lacks a tumor phenotype in p73-deficient mice. We recently reported that an N-terminally truncated isoform, DeltaNp73, is upregulated in breast and gynecological cancers. We further showed that DeltaNp73 is a potent transdomit inhibitor of wild-type p53 and TAp73 in cultured human tumor cells by efficiently counteracting their target gene transactivations, apoptosis, and growth suppression functions (A. I. Zaika et al., J. Exp. Med. 6:765-780, 2002). Although these data strongly suggest oncogenic properties of DeltaNp73, this can only be directly shown in primary cells. We report here that DeltaNp73 confers resistance to spontaneous replicative senescence of primary mouse embryo fibroblasts (MEFs) and immortalizes MEFs at a 1,000-fold-higher frequency than occurs spontaneously. DeltaNp73 cooperates with cMyc and E1A in promoting primary cell proliferation and colony formation and compromises p53-dependent MEF apoptosis. Importantly, DeltaNp73 rescues Ras-induced senescence. Moreover, DeltaNp73 cooperates with oncogenic Ras in transforming primary fibroblasts in vitro and in inducing MEF-derived fibrosarcomas in vivo in nude mice. Wild-type p53 is likely a major target of DeltaNp73 inhibition in primary fibroblasts since deletion of p53 or its requisite upstream activator ARF abrogates the growth-promoting effect of DeltaNp73. Taken together, DeltaNp73 behaves as an oncogene that targets p53 that might explain why DeltaNp73 upregulation may be selected for during tumorigenesis of human cancers. p73 is a p53 paralog that encodes proapoptotic (transactivation-competent (TA)) and antiapoptotic (domit negative) isoforms. TAp73 transcription factors mediate cell cycle arrest and/or apoptosis in response to DNA damage and are involved in developmental processes in the central nervous system and the immune system. p73 proteins may also play a role in the regulation of cell growth. Indeed, p73 expression is itself modulated during the cell cycle and TAp73 proteins accumulate in S phase cells. In addition, the function of p73 proteins is also regulated by post-translational modifications and protein-protein interactions in different cellular and pathophysiological contexts. Here we show that p73 is a physiological target of the p34cdc2-cyclin B mitotic kinase complex in vivo. Both p73beta and p73alpha isoforms are hyperphosphorylated in normal mitotic cells and during mitotic arrest induced by microtubule-targeting drugs. p34cdc2-cyclin B phosphorylates and associates with p73 in vivo, which results in a decreased ability of p73 to both bind DNA and activate transcription in mitotic cells. Indeed, p73 is excluded from condensed chromosomes in meta- and anaphase, redistributes throughout the mitotic cytoplasm, and unlike p53, shows no association with centrosomes. Together these results indicate that M phase-specific phosphorylation of p73 by p34cdc2-cyclin B is associated with negative regulation of its transcriptional activating function. p73, an important developmental gene, shares a high sequence homology with p53 and induces both G(1) cell cycle arrest and apoptosis. However, the molecular mechanisms through which p73 induces apoptosis are unclear. We found that p73-induced apoptosis is mediated by PUMA (p53 up-regulated modulator of apoptosis) induction, which, in turn, causes Bax mitochondrial translocation and cytochrome c release. Overexpression of p73 isoforms promotes cell death and bax promoter transactivation in a time-dependent manner. However, the kinetics of apoptosis do not correlate with the increase of Bax protein levels. Instead, p73-induced mitochondrial translocation of Bax is kinetically compatible with the induction of cell death. p73 is localized in the nucleus and remains nuclear during the induction of cell death, indicating that the effect of p73 on Bax translocation is indirect. The ability of p73 to directly transactivate PUMA and the direct effect of PUMA on Bax conformation and mitochondrial relocalization suggest a molecular link between p73 and the mitochondrial apoptotic pathway. Our data therefore indicate that PUMA-mediated Bax mitochondrial translocation, rather than its direct transactivation, correlates with cell death. Finally, human DeltaNp73, an isoform lacking the amino-terminal transactivation domain, inhibits TAp73-induced as well as p53-induced apoptosis. The DeltaNp73 isoforms seem therefore to act as domit negatives, repressing the PUMA/Bax system and, thus, finely tuning p73-induced apoptosis. Our findings demonstrate that p73 elicits apoptosis via the mitochondrial pathway using PUMA and Bax as mediators. The p73 gene is able to encode transcriptionaly active TAp73, as well as a domit-negatively acting DeltaNp73 transcript isoforms. We studied differential expression of these forms in normal brain as well as glial tumors, by semiquantitative RT-PCR. The expression of p73 was low or undetectable in normal brain tissues. Most of the tumors and non-tumor brain tissues also lacked significant expression of p73 in patients with low-grade astrocytomas. In contrast, most high-grade glial tumors displayed strong up-regulation of TAp73, whereas only a few displayed DeltaNp73 expression. These aberrations may reflect the inactivation of retinoblastoma pathway in these tumors which result in the activation of E2F transcription factors, since TAp73 is a known target of E2F1 gene. The study of TAp73 expression in brain tumors may serve as a means to evaluate the retinoblastoma pathway-dependent tumor progression. p53 family members with a transactivation (TA) domain induce cell cycle arrest and promote apoptosis. However, DeltaNp63 isotypes lacking the TA-domain promote cell proliferation and tumorigenesis in vitro and in vgammavo. Although p53, TAp63 or TAp73 are stabilized upon DNA damage, we found that the genotoxic stress agents induced a dramatic decrease and phosphorylation of DeltaNp63alpha in squamous cell carcinoma cells. Further work revealed that RACK1 physically associated with the p63alpha C-terminal domain through its WD40 domain. However, stratifin binds with phosphorylated DeltaNp63alpha in response to cisplatin. Upon DNA damage induced by cisplatin, stratifin mediated a nuclear export of DeltaNp63alpha into cytoplasm and then RACK1 targeted latter into a proteasome degradation pathway possibly serving as an E3 ubiquitin ligase. Moreover, siRNA knockdown of both stratifin and RACK1 inhibited a nuclear export and protein degradation of DeltaNp63alpha, respectively. Our data suggest that modification and down regulation of DeltaNp63alpha is one of the major determits of the cellular response to DNA damage in human head and neck cancers. Tazarotene, a member of the new class of acetylenic retinoids, has been shown to be effective in the treatment of several hyperproliferative skin diseases, including non-melanoma skin cancer. Its effectiveness is thought to rely on the ability to activate retinoic acid receptors beta and gamma and to induce a number of downstream anti-proliferative genes. Here, we show that the p53-related gene p73 is a target of tazarotene. Indeed, tazarotene modulates the expression of the p73 gene in immortalized keratinocyte cell lines by inducing the pro-apoptotic and anti-proliferative TAp73 isoforms and by repressing the anti-apoptotic and pro-proliferative DeltaNp73 isoforms. This occurs at the transcriptional level through a coordinated action on P1p73 and P2p73 promoters that control the expression of TA and DeltaN isoforms, respectively. The selective downregulation of DeltaNp73 expression by small interfering RNA led to an enhancement of tazarotene-induced bax activation and apoptosis, whereas the downregulation of both TA and DeltaN isoforms impairs tazarotene-mediated apoptosis. These results indicate the relevance of p73 gene products in tazarotene-induced growth inhibition and effectiveness in the treatment of skin tumors. The p53 gene and its homologue p73 are rarely mutated in neuroblastoma. In recent studies, we showed that overexpression of DeltaNp73alpha, an isoform lacking the N-terminal transactivation (TA) domain, surprisingly induces p53 protein accumulation in the wild-type (wt) p53 human neuroblastoma line SH-SY5Y. As can be expected owing to its domit-negative effect, DeltaNp73alpha inhibits Waf1/p21 gene expression, but equally importantly, it upregulates BTG2TIS21/PC3, another p53 target gene. This effect is not observed in neuroblastoma cells that express a mutated p53. To better understand the DeltaNp73-mediated transactivation of the BTG2TIS21/PC3 gene we performed luciferase assays with two reporter plasmids harboring long and short BTG2 promoter sequences in three human neuroblastoma cell lines and one breast cancer cell line. Our results demonstrate that BTG2TIS21/PC3 transactivation by DeltaNp73alpha depends on both p53 status (as it is not observed in a p53-/- neuroblastoma cell line) and cellular context (as it occurs in a p53+/+ neuroblastoma cell line but not in a p53+/+ breast tumor cell line). The fact that DeltaNp73alpha may either inhibit or stimulate wt-p53 transcriptional activity, depending on both the p53 target gene and the cellular context, was confirmed by real-time quantitative PCR. Moreover, transactivation of the BTG2TIS21/PC3 promoter requires a complete DeltaNp73alpha C-terminus sequence as it is not observed with DeltaNp73beta, which lacks most of the C-terminal domain. We have previously shown that DeltaNp73alpha is the only p73 isoform expressed in undifferentiated neuroblastoma tumors. In light of all these findings, we propose that DeltaNp73alpha not only acts as an inhibitor of p53/TAp73 functions in neuroblastoma tumors, but also cooperates with wt-p53 in playing a physiological role through the activation of BTG2TIS21/PC3 gene expression. BACKGROUND: To clarify the role of p53 homologs in oncogenesis and cytodifferentiation of odontogenic tumors, expression of p63 and p73 was analyzed in ameloblastomas as well as tooth germs. METHODS: Tissue specimens of nine tooth germs and 48 benign and five maligt ameloblastomas were examined by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) for the expression of p63 and p73. RESULTS: Immunoreactivity for p63 and p73 was evident in epithelial cells neighboring the basement membrane in developing and neoplastic odontogenic tissues. p63 expression in desmoplastic ameloblastomas was significantly higher than in acanthomatous and granular cell ameloblastomas, and ameloblastic carcinomas showed higher p63 expression than metastasizing ameloblastomas. p73 expression was significantly higher in plexiform ameloblastomas than in follicular ameloblastomas, and basal cell ameloblastomas showed higher p73 expression than granular cell ameloblastomas. mRNA transcripts for Delta Np63 and TAp73 were detected in all developing and neoplastic odontogenic tissues. TAp63 mRNA was expressed in five of eight tooth germs, 16 of 34 ameloblastomas, and one of one maligt ameloblastoma, whereas Delta Np73 mRNA was recognized in one of eight tooth germs, nine of 34 ameloblastomas, and one of one maligt ameloblastoma. CONCLUSION: The expression of p63 and p73 suggests that these p53 homologs play a role in differentiation and proliferation of odontogenic epithelial cells. Variations of predomitly expressed isoforms suggest that p63 and p73 might differentially function in odontogenic tissues. p73, unlike p53, is expressed as a number of isomeric forms. Alternative splicing at the 3' end of p73 transcript, together with the usage of a second promoter downstream of exon 3, can generate up to 24 p73 isoforms. Variants lacking the TA domain (DeltaN isoforms) are induced by TAp73 and by p53, and inhibit their transcriptional activity. However, understanding the complex biology of p73 has been handicapped by the lack of high affinity specific antibodies for the different isoforms. Here, we report the characterization, by Western blotting and immunoprecipitation, of three new polyclonal antisera recognizing all p73 isoforms, only DeltaN isoforms or only p73alpha, and which have advantages of affinity and specificity over previously available antibodies. The p73 gene codes for various different protein isoforms. They include proteins expressed under the control of the P1 promoter that contain a transactivation domain and are similar in function to p53 (TAp73 isoforms), as well as proteins regulated by the P2 promoter that lack this domain and function as domit negative inhibitors of TAp73 and p53 (DeltaNp73 isoforms). Whereas TAp73 functions as a tumor suppressor with pro-apoptotic function, DeltaNp73 is likely to prevent the induction of apoptosis in tumor cells and to participate in oncogenesis. Here we used a loss-of-function strategy to assess the role of DeltaNp73 in SH-SY5Y neuroblastoma cells. An antisense oligonucleotide designed to target DeltaNp73 mRNA, but not TAp73, was used to effectively downregulate this transcript. DeltaNp73 downregulation was accompanied by increased levels of the pro-apoptotic BH3 family member PUMA at the mRNA and protein level, and by conformational activation of BAX which translocated to mitochondria. These DeltaNp73 antisense-mediated alterations led to the induction of apoptosis as detected by decreased cell viability, augmented DNA fragmentation and increased caspase-3 activity in cell lysates. Our results demonstrate the cytoprotective role of DeltaNp73 in neuroblastoma and suggest its use as a target for molecular intervention therapy. PURPOSE: To determine the protein and mRNA expression of p53, p63, and p73 in central and peripheral human corneal endothelial cells. Since these proteins are known to be involved in the regulation of cell division, this study seeks information about their influence in regulating cell proliferation in the human corneal endothelium. METHODS: Human donor corneas were separated into central and peripheral sections. The endothelial tissue from these samples was dissected and samples were analyzed for mRNA transcription of p53, transactivating p63 (TAp63), delta N p63 (DeltaNp63), transactivating p73 (TAp73), and delta N p73 (DeltaNp73) via the reverse transcriptase-polymerase chain reaction (RT-PCR). Additional samples were analyzed for p53, p63, and p73 protein expression via SDS-PAGE, western blotting, and immunodetection. Frozen corneal sections were immunostained for p53 and analyzed via fluorescence microscopy. RESULTS: p53 and TAp63 mRNA and protein expression were detected in central and peripheral human corneal endothelium. p53 and TAp63 protein expression were greater in central than in peripheral tissue. DeltaNp63 and all isoforms of p73 were not detected in either central or peripheral corneal endothelium. CONCLUSIONS: p53 is expressed in both peripheral and central human corneal endothelium, although it is more highly expressed in the central endothelium. Similarly, TAp63 is more highly expressed in central rather than in peripheral endothelium. This suggests that the peripheral endothelium may have more potential for cell division than the central endothelium. DeltaNp63, a stem cell marker, was not detected in the corneal endothelium. Neither the TAp73 nor the DeltaNp73 isoforms were detected in either central or peripheral human corneal endothelium. BACKGROUND: The p73 gene is a p53 homologue that induces apoptosis and inhibits cell proliferation. N-terminal truncated isoforms of p73 (DeltaNp73) act as domit-negative inhibitors of wild-type p53 and TAp73 and result in tumour growth in nude mice. AIMS: To detect DeltaNp73 expression in 24 benign prostatic hyperplasia samples, 33 prostate carcinomas, and five normal samples and to evaluate the relation between DeltaNp73, TAp73 concentrations, and the clinicopathological characteristics of patients with prostate cancer. METHODS: TAp73 was determined by real time polymerase chain reaction (PCR); DeltaNp73 and DeltaN'p73 were assessed using reverse transcription PCR. western blotting was used to analyse protein expression. p53 mutation was determined by immunohistochemistry. RESULTS: A significant increase of DeltaNp73 was seen in 20 of 33 carcinomas and 17 of 24 benign prostate hyperplasia tissues, but in none of the normal samples. None of the specimens expressed DeltaN'p73. No significant relation was found between TAp73 expression and clinical parameters. The incidence of positive expression of DeltaNp73 correlated with the Gleason score in prostate carcinomas. Cancer samples with wild-type p53 had significantly higher expression of DeltaNp73 than p53 mutant cancers. CONCLUSION: These data suggest a potential role for DeltaNp73 in prostate cancer progression. AIM: This study was aimed to determine p73 status in thyroid tumours. METHODS: Differential expression of the TAp73, DeltaTAp73 transcripts was measured in a panel of 60 thyroid maligcies by quantitative RT-PCR. RESULTS: By comparison to normal thyroid tissue surrounding the tumours, we observed significant downregulation of TP73 transcripts in adenomas and in differentiated carcinomas. Correlations were found in normal tissue specimens between the expression of TAp73 and DeltaNp73 transcripts and that of p53, p14ARF p16INK4a, but these correlations were lost in carcinomas (PTC or FTC). CONCLUSIONS: We have found significant variations of TAp73, DeltaNp73, p53, p14ARF p16INK4a, expressions and correlations between the expressions of those different genes in thyroid cancer. PURPOSE: We aimed to determine the clinical role of the p53 family members p53 and p73 in the responsiveness to platinum-based chemotherapy and survival in ovarian cancer, considering their cross-talk and the p53 polymorphism at codon 72. EXPERIMENTAL DESIGN: A detailed analysis of p53 and p73 in a series of 122 ovarian cancers was done. We used a functional yeast-based assay to determine the p53 mutational status. Red yeast colonies, indicating mutant p53, were subsequently sequenced to determine the specific p53 alteration. p53 mutations were divided into two groups according to their previous characterization in the literature: those that efficiently inhibit transcriptionally active TAp73 function and those that do not. A p53 polymorphism at codon 72 was determined in corresponding normal tissue or blood of ovarian cancer patients. Isoform-specific p73 expression analysis using real-time reverse transcription-PCR has previously been done in the majority of ovarian cancers included in this study. In a retrospective chart review, responsiveness to chemotherapy was assessed, and survival data with long follow-up times were collected. RESULTS: Eighty of 122 (65.6%) of ovarian cancers harbored p53 mutations. p53 mutational status was an important determit of responsiveness to platinum-based chemotherapy in all patients with a residual tumor of <2 cm in diameter after initial surgery (wild-type versus mutant, P = 0.029). In addition, p53 mutational status was a strong prognosticator for recurrence-free and overall survival (P < 0.0001 and P = 0.003, respectively) in univariate analyses. High expression levels of domit-negative p73 isoforms (DeltaNp73 and DeltaN'p73) significantly correlated with chemotherapeutic failure (P = 0.048) and with worse recurrence-free and overall survival in patients with p53 mutant cancers (P = 0.048 and P = 0.005, respectively). Eight p53 mutations, present in 19 cases, were found that efficiently inhibit TAp73 (i.e., 175H, 220C, 245S, 245D, 248W, 248Q, 266E, and 273H). Patients with p53 mutations that efficiently inhibit TAp73 function had a significantly shorter overall survival than patients with p53 mutations of unknown effect on TAp73 (P = 0.044). The p53 polymorphism at codon 72 had no influence on responsiveness to chemotherapy or survival. CONCLUSION: We provide the first clinical evidence that domit-negative p73 isoforms contribute to drug resistance in vivo, underscoring the importance of a p53-p73 cross-talk. NH2-terminally truncated p73 isoforms were of significant clinical effect by providing an additional unfavorable factor for response to platinum-based chemotherapy and survival in p53 mutant ovarian cancers. We found that MEK1 inhibitor PD184352 strikingly increased apoptosis induced by arsenic trioxide (ATO) in 21 of 25 patients with primary acute myelogenous leukemia (AML). Isobologram analysis confirmed the synergistic (13 of 25 patients) or additive (8 of 25 patients) nature of this interaction. Moreover, we demonstrated that the p53-related gene p73 is a molecular target of the combined treatment in AML blasts. Indeed, ATO modulates the expression of the p73 gene by inducing the proapoptotic and antiproliferative TAp73 and the antiapoptotic and proproliferative DeltaNp73 isoforms, thereby failing to elevate the TA/DeltaNp73 ratio. Conversely, treatment with PD184352 reduces the level of DeltaNp73 and blunts the arsenic-mediated up-regulation of DeltaNp73, thus causing an increase in the TA/DeltaNp73 ratio of dual-treated cells. High doses of ATO induced p53 accumulation in 11 of 21 patients. Combined treatment resulted in the induction of the proapoptotic p53/p73 target gene p53AIP1 (p53-regulated apoptosis-inducing protein 1) and greatly enhanced the apoptosis of treated cells. The goal of this study was to determine whether patterns of expression profiles of p73 isoforms and of p53 mutational status are useful combinatorial biomarkers for predicting outcome in a gynecological cancer cohort. This is the first such study using matched tumor/normal tissue pairs from each patient. The median follow-up was over two years. The expression of all 5 N-terminal isoforms (TAp73, DeltaNp73, DeltaN'p73, Ex2p73 and Ex2/3p73) was measured by real-time RT-PCR and p53 status was analyzed by immunohistochemistry. TAp73, DeltaNp73 and DeltaN'p73 were significantly upregulated in tumors. Surprisingly, their range of overexpression was age-dependent, with the highest differences delta (tumor-normal) in the youngest age group. Correction of this age effect was important in further survival correlations. We used all 6 variables (five p73 isoform levels plus p53 status) as input into a principal component analysis with Varimax rotation (VrPCA) to filter out noise from non-disease related individual variability of p73 levels. Rationally selected and individually weighted principal components from each patient were then used to train a support vector machine (SVM) algorithm to predict clinical outcome. This SVM algorithm was able to predict correct outcome in 30 of the 35 patients. We use here a mathematical tool for pattern recognition that has been commonly used in e.g. microarray data mining and apply it for the first time in a prognostic model. We find that PCA/SVM is able to test a clinical hypothesis with robust statistics and show that p73 expression profiles and p53 status are useful prognostic biomarkers that differentiate patients with good vs. poor prognosis with gynecological cancers. Mutations in p73 are rare in cancer. Emerging evidence suggests that the relative expression of various p73 isoforms may contribute to tumorigenesis. Alternative promoters and N-terminal splicing result in the transcription and processing of either full-length (TA) or N-terminally truncated (deltaN) p73 isoforms. TAp73 possesses pro-apoptotic functions, while deltaNp73 has anti-apoptotic properties via functional inhibition of TAp73 and p53. Here, we report that TAp73, but not deltaNp73, is covalently modified by NEDD8 under physiologic conditions in an Mdm2-dependent manner. Co-expression of NEDP1, a cysteine protease that specifically cleaves NEDD8 conjugates, was shown to deneddylate TAp73. In addition, blockage of the endogenous NEDD8 pathway increased TAp73-mediated transactivation of p53- and p73-responsive promoter-driven reporter activity, and in conjunction, neddylated TAp73 species were found preferentially in the cytoplasm. These results suggest that Mdm2 attenuates TAp73 transactivation function, at least in part, by promoting NEDD8-dependent TAp73 cytoplasmic localization and provide the first evidence of a covalent post-translational modification exclusively targeting the TA isoforms of p73. Glial tumours are a devastating, poorly understood condition carrying a gloomy prognosis for which clinicians sorely lack reliable predictive parameters facilitating a sound treatment strategy. Tp73, a p53 family member, expresses two main classes of isoforms--transactivatory activity (TA)p73 and DeltaTAp73--exhibiting tumour suppressor gene and oncogene properties, respectively. The authors examined their expression status in high- and low-grade adult gliomas. Isoform-specific real-time reverse transcription-polymerase chain reaction was used for the analysis of Tp73 isoform transcript expression in a series of 51 adult patients harbouring glial tumours, in order to compare tumour grades with each other, and with non-tumoural samples obtained from epileptic patients as well. Our data demonstrate increase of TAp73 and DeltaTAp73 transcript levels at onset and early stage of the disease. We also show that DeltaEx2-3 isoform expression in low-grade tumours anticipates clinical and imaging progression to higher grades, and correlates to the patients' survival. Expression levels of P1 promoter generated Tp73 isoforms--and particularly DeltaEx2-3--indeed allow for prediction of the clinical progression of low-grade gliomas in adults. Our data are the first such molecular biology report regarding low-grade tumours and as such should be of help for sound decision-making. p73, like Notch, has been implicated in neurodevelopment and in the maintece of the mature central nervous system. In this study, by the use of reporter-gene assays, we demonstrate that C-promoter binding factor-1 (CBF-1)-dependent gene transcription driven by the Notch-1 intracellular domain (N1(ICD)) is potently antagonized by exogenously expressed transactivating (TA) p73 splice variants in SH-SY5Y neuroblastomas and in primary neurones. Time course analysis indicated that the inhibitory effects of TAp73 are direct and are not mediated via the product of a downstream target gene. We found that endogenous TAp73 stabilized by either c-Abl or cisplatin treatment also potently antagonized N1(ICD)/CBF-1-dependent gene transcription. Furthermore, western blotting revealed that exogenous TAp73 suppressed endogenous hairy and enhancer of split-1 (HES-1) protein levels and antagonized the increase in HES-1 protein induced by exogenous N1(ICD) expression. Evidence of a direct physical interaction between N1(ICD) and TAp73alpha was demonstrated by co-immunoprecipitation. Using Notch deletion constructs, we demonstrate that TAp73alpha binds the N1(ICD) in a region C-terminal of aa 2094. Interestingly, DeltaNp73alpha and TAp73alpha(R292H) also co-purified with N1(ICD), but neither inhibited N1(ICD)/CBF-1-dependent transcription. This suggests that an intact transactivation (TA) domain and the ability to bind DNA are necessary for TAp73 to antagonize Notch signalling. Finally we found that TAp73alpha reversed the N1(ICD)-mediated repression of retinoic acid-induced differentiation of SH-SY5Y neuroblastomas, providing functional evidence for an inhibitory effect of TAp73alpha on notch signalling. Collectively, these findings may have ramifications for neurodevelopment, neurodegeneration and oncogenesis. Breast cancers lacking estrogen and progesterone receptor expression and Her2 amplification exhibit distinct gene expression profiles and clinical features, and they comprise the majority of BRCA1-associated tumors. Here we demonstrated that the p53 family member p63 controls a pathway for p73-dependent cisplatin sensitivity specific to these "triple-negative" tumors. In vivo, DeltaNp63 and TAp73 isoforms were coexpressed exclusively within a subset of triple-negative primary breast cancers that commonly exhibited mutational inactivation of p53. The DeltaNp63alpha isoform promoted survival of breast cancer cells by binding TAp73 and thereby inhibiting its proapoptotic activity. Consequently, inhibition of p63 by RNA interference led to TAp73-dependent induction of proapoptotic Bcl-2 family members and apoptosis. Breast cancer cells expressing DeltaNp63alpha and TAp73 exhibited cisplatin sensitivity that was uniquely dependent on TAp73. Thus, in response to treatment with cisplatin, but not other chemotherapeutic agents, TAp73 underwent c-Abl-dependent phosphorylation, which promoted dissociation of the DeltaNp63alpha/TAp73 protein complex, TAp73-dependent transcription of proapoptotic Bcl-2 family members, and apoptosis. These findings define p63 as a survival factor in a subset of breast cancers; furthermore, they provide what we believe to be a novel mechanism for cisplatin sensitivity in these triple-negative cancers, and they suggest that such cancers may share the cisplatin sensitivity of BRCA1-associated tumors. BACKGROUND: Medulloblastoma is the most common maligt brain tumor of childhood. Children who relapse usually die of their disease, which reflects resistance to radiation and/or chemotherapy. Improvements in outcome require a better understanding of the molecular basis of medulloblastoma growth and treatment response. TP73 is a member of the TP53 tumor suppressor gene family that has been found to be overexpressed in a variety of tumors and mediates apoptotic responses to genotoxic stress. In this study, we assessed expression of TP73 RNA species in patient tumor specimens and in medulloblastoma cell lines, and manipulated expression of full-length TAp73 and amino-terminal truncated DeltaNp73 to assess their effects on growth. METHODS: We analyzed medulloblastoma samples from thirty-four pediatric patients and the established medulloblastoma cell lines, Daoy and D283MED, for expression of TP73 RNA including the full-length transcript and the 5'-terminal variants that encode the DeltaNp73 isoform, as well as TP53 RNA using quantitative real time-RTPCR. Protein expression of TAp73 and DeltaNp73 was quantitated with immunoblotting methods. Clinical outcome was analyzed based on TP73 RNA and p53 protein expression. To determine effects of overexpression or knock-down of TAp73 and DeltaNp73 on cell cycle and apoptosis, we analyzed transiently transfected medulloblastoma cell lines with flow cytometric and TUNEL methods. RESULTS: Patient medulloblastoma samples and cell lines expressed full-length and 5'-terminal variant TP73 RNA species in 100-fold excess compared to non-neoplastic brain controls. Western immunoblot analysis confirmed their elevated levels of TAp73 and amino-terminal truncated DeltaNp73 proteins. Kaplan-Meier analysis revealed trends toward favorable overall and progression-free survival of patients whose tumors display TAp73 RNA overexpression. Overexpression of TAp73 or DeltaNp73 induced apoptosis under basal growth conditions in vitro and sensitized them to cell death in response to chemotherapeutic agents. CONCLUSION: These results indicate that primary medulloblastomas express significant levels of TP73 isoforms, and suggest that they can modulate the survival and genotoxic responsiveness of medulloblastomas cells. p53, p63 and p73 are members of the p53 gene family involved in development, differentiation and response to cellular stress. p53 gene is a transcription factor essential for the prevention of cancer formation. The p53 pathway is ubiquitously lost in human cancer either by p53 gene mutation (60% of cancers) or by lost of cell signalling upstream and downstream of p53 in the remaining cancers expressing WTp53 gene. As p53 pathway inactivation is a common denominator to all cancers, the understanding of p53 tumour suppressor activity is likely to bring us closer to cancer therapy. However, despite all the experimental evidences showing the importance of p53 in preventing carcinogenesis, it is difficult in clinical studies to link p53 status to cancer treatment and clinical outcome. The recent discovery that p53 gene encodes for nine different p53 proteins (isoforms) may have a profound impact on our understanding of p53 tumour suppressor activity. Studies in several tumour types have shown that the nine different p53 isoforms are abnormally expressed in tumour tissues compared to normal cells. p53 protein isoforms modulate p53 transcriptional activity and cell fate outcome in response to stress. Regulation of p53 function in normal and tumour tissues in man is likely to be more complex than has been hitherto appreciated. Therefore, the tumour p53 status needs to be determined more accurately by integrating p53 isoform expression, functional p53 mutation analysis and a panel of antibodies specific of p53 and of its target genes. The human p73 protein is essential for normal morphogenesis and maintece of neural tissue. Recently, several TP73 transcripts have been revealed in medulloblastoma (MB), the most common maligt brain tumor in children. Here, we performed immunohistochemical analysis on 29 MB specimens using anti-p73alpha and anti-DeltaNp73 antibodies. Real-time PCR quantification was performed to assess TAp73 and DeltaNp73 transcripts in a subset of 13 MB samples. Normal cerebellar tissues and RNA were used for comparison. Pilot clinical-pathological correlations were also provided. We report significant differences for TAp73 and DeltaNp73 mRNA expression between tumor tissues and reference (P = 0.013, P = 0.028). Immunohistochemically, 52 and 29% MB samples were positive for p73alpha and DeltaNp73, respectively. p73alpha expression was found to be in both the nucleus and cytoplasm, whereas DeltaNp73 was localized predomitly in the cytoplasm. In normal cerebellum, positive staining for p73alpha and DeltaNp73 was observed in the Purkinje cells of newborns, not adult samples, which supports the developmental role of TP73 during organogenesis of the human cerebellum. Survival analysis has shown negative relationship of DeltaNp73-immunoreactivity with overall survival (OS) and event free survival (EFS) (P = 0.026 and P = 0.127, respectively). For p73alpha-positive cases, the negative trend in OS (P = 0.149) and EFS (P = 0.216) was also apparent. Our results indicate the involvement of p73 protein in MB tumorigenesis and define TP73 as a potential prognostic and therapeutic target for medulloblastoma. The p53 gene has been investigated for its role in epithelial ovarian cancer but data collected until now are contradictory. The evidence that p53 belongs with p63 and p73 to a family of transcription factors re-opened interest in this gene family. Here, we used quantitative real time RT-PCR to determine expression levels of TAp53, TAp73 and their N-terminal splice variants in a cohort of 169 ovarian cancer patients with stage I and stage III disease. The TAp73 levels in stage III biopsies differed by 100-fold depending on the p53 status and overall survival appears to be significantly related to DeltaNp73 expression. Kaplan-Meyer analyses did not suggest a correlation between overall survival and levels of TAp73, DeltaNp73 or the DeltaNp73/TAp73 ratio. In conclusion, these data suggest that at least in our patient cohort p53 and p73 expression levels are not correlated to maligt progression of ovarian cancer. They might, however, play a role in tumour initiation. A member of the p53 family, p73, has several isoforms and differentially regulates transcription of genes involved in the control of the cell cycle and apoptosis. We have previously shown efficient and p53-independent, tumor-specific cell death induced by the viral proteins E1A and Apoptin. Here, we demonstrate that the induction of apoptosis by these viral proteins involves activation of TAp73. Both E1A and Apoptin induced expression of endogenous TAp73 and the p53/p73 BH3-only pro-apoptotic target, PUMA, independently of the p53 function. Furthermore, exogenous expression of TAp73 isoforms, particularly TAp73beta, sensitized cells to killing by both E1A and Apoptin, while expression of DeltaNp73alpha blocked this activity. Besides, knockout of the p73 regulator, c-Abl, attenuated E1A-induced apoptosis. In accordance with the role of p73 in apoptosis induced by these viral proteins, overexpression of TAp73beta strongly induced apoptosis in p53-deficient cancer cells in vitro and in HNSCC xenografts. Using a doxycycline-inducible system, we provide evidence for target selectivity and significant differences in protein stability for specific p73 isoforms, suggesting a diverse and pivotal role for p73 in response to various genotoxic agents. Collectively, our data show that in the absence of the p53 function, viral proteins E1A and Apoptin utilize the p73 pathway to induce efficient tumor cell death. p73, a member of the p53 family, exhibits activities similar to those of p53, including the ability to induce growth arrest and apoptosis. p73 influences chemotherapeutic responses in human cancer patients, in association with p53. Alternative splicing of the TP73 gene produces many p73 C- and N-terminal isoforms, which vary in their transcriptional activity towards p53-responsive promoters. In this paper, we show that the C-terminal spliced isoforms of the p73 protein differ in their DNA-binding capacity, but this is not an accurate predictor of transcriptional activity. In different p53-null cell lines, p73beta induces either mitochondrial-associated or death receptor-mediated apoptosis, and these differences are reflected in different gene expression profiles. In addition, p73 induces cell cycle arrest and p21(WAF1) expression in H1299 cells, but not in Saos-2. This data shows that TAp73 isoforms act differently depending on the tumour cell background, and have important implications for p73-mediated therapeutic responses in individual human cancer patients. The Brn-3a/POU4F1 POU transcription factor is critical for the survival and differentiation of specific sensory neurons during development or upon injury; by regulating expression of target genes, either directly or indirectly upon interaction with other proteins. In this study, we demonstrated the physical interaction of Brn-3a with different p73 isoforms and showed co-localization in sensory neurons arising from the neural crest. The biological effects of p73/ Brn-3a interaction depend on the particular p73 isoform, because co-expression of Brn-3a with TAp73 enhanced cell cycle arrest, whereas Brn-3a and DeltaNp73 cooperated to increase protection from apoptosis. Brn-3a antagonized TAp73 transactivation of pro-apoptotic Bax, but co-operated to increase transcription of the cell cycle regulator p21 CIP1/Waf1. The region 425-494 amino acids within the TAp73 C terminus were critical for Brn-3a to repress Bax transactivation, but not for cooperation on the p21 CIP1/Waf1 promoter. Our results suggest that co-factors binding to the p73 C terminus facilitate maximal activation on the Bax but not p21 CIP1/Waf1 promoter and that Brn-3a modulates this interaction. Thus, the physical interaction of Brn-3a with specific p73 isoforms will be critical for determining cell fate during neuronal development or in injured neurons expressing both factors. The secreted mitogen vascular endothelial growth factor, VEGF, plays a pivotal role in angiogenesis. Hypoxia, inactivation of p53 and oncogenic K-Ras induce VEGF expression. Other factors such as p73 may also affect VEGF levels. Curiously, p73 may also regulate angiogenesis by affecting the expression of the pigment epithelium-derived factor, PEDF. Additionally, VEGF might harbor additional functions through the activation of E2F transcription factors. Recently, a new VEGF variant formed by alternative splicing, VEGF(165)b, has been described as exerting anti-angiogenic activity. We study here whether p73 isoforms levels -TAp73 and DeltaTAp73- and p53 and K-Ras status affect the expression of the above-mentioned angiogenesis-related genes (through the correlation between their expressions), the prognostic value of VEGF(165)b and PEDF and the correlation between VEGF and E2F-1 levels. Tumor and normal tissue of 112 colorectal cancer patients was analyzed to evaluate: (i) levels of TAp73, DeltaTAp73, VEGF, VEGF(165)b, PEDF and E2F-1 by quantitative real-time RT-PCR, (ii) p53 status by immunohistochemistry and (iii) mutations in the first exon of K-Ras by PCR-SSCP. Tumor characteristics were examined in each patient. Associations were observed between: (i) specific p73 isoforms and VEGF and VEGF(165)b expression; (ii) DeltaEx2p73 variant and downregulation of PEDF; (iii) VEGF and PEDF expression; (iv) inactive p53 and VEGF(165)b levels; (v) oncogenic K-Ras and PEDF downregulation; (vi) E2F-1 and VEGF expressions; (vii) VEGF(165)b downregulation and poor prognosis parameters of tumors. We conclude that the levels of p73 isoforms could affect the expression of VEGF, VEGF(165)b and PEDF. This scenario becomes complicated because a feedback between VEGF and PEDF may exist. VEGF may activate the E2F-1 factor. Mutations in K-Ras could negatively regulate PEDF expression. p53 inactivation might result in compensatory mechanisms such as over-expression of VEGF(165)b. Our data support the role of VEGF(165)b as a tumor suppressor factor in colorectal carcinogenesis and its possible prognosis value. The role of various p73 isoforms in tumorigenesis has been controversial. However, as we have recently shown, the generation of TAp73-deficient (TAp73(-/-)) mice reveals that TAp73 isoforms exert tumor-suppressive functions, indicating an emerging role for Trp-73 in the maintece of genomic stability. Unlike mice lacking all p73 isoforms, TAp73(-/-) mice show a high incidence of spontaneous tumors. Moreover, TAp73(-/-) mice are infertile and produce oocytes exhibiting spindle abnormalities. These data suggest a link between TAp73 activities and the common molecular machinery underlying meiosis and mitosis. Previous studies have indicated that the spindle assembly checkpoint (SAC) complex, whose activation leads to mitotic arrest, also regulates meiosis. In this study, we demonstrate in murine and human cells that TAp73 is able to interact directly with several partners of the SAC complex (Bub1, Bub3, and BubR1). We also show that TAp73 is involved in SAC protein localization and activities. Moreover, we show that decreased TAp73 expression correlates with increases of SAC protein expression in patients with lung cancer. Our results establish TAp73 as a regulator of SAC responses and indicate that TAp73 loss can lead to mitotic arrest defects. Our data suggest that SAC impairment in the absence of functional TAp73 could explain the genomic instability and increased aneuploidy observed in TAp73-deficient cells. The p53 homologue p73 is overexpressed in many tumors, including lung cancer. We have evaluated the differential expression and subcellular localization of the functionally distinct apoptotic (TA) and anti-apoptotic (DeltaN) isoforms of p73 in non-small cell lung cancer (NSCLC), their possible association with p53 expression and determined the methylation status of the two p73 gene promoters (P1 and P2) in this tumor type. Immunohistochemical analysis showed that both isoforms are expressed in the majority of cases. However, the oncogenic DeltaN variant, derived from the transcripts DeltaN'p73 (from P1) and/or DeltaNp73 (from P2), is localized mainly in the nucleus, while the anti-oncogenic TAp73 isoform (derived from a P1 transcript) is sequestered in the cytoplasm in almost all cases analyzed. Significant correlation was found between p53 and DeltaNp73 expression (p=0.041). Methylation analysis conducted on 41 tumor samples showed that the P1 promoter is almost invariably unmethylated (39/41 cases) whereas P2 was found completely methylated in 17 cases and partially or totally unmethylated in 24 samples. No correlation was found between the methylation status of P1 and P2 and p73 expression. Our results demonstrate that both isoforms contribute to p73 overexpression in NSCLC and suggest that their different intracellular localization may reflect an alteration of the functional p53-p73 network that might contribute to lung cancer development. p63 and p73 express two main classes of isoforms: isoforms which contain the transactivation domain (TAp73 and TAp63) executing transcriptional activity and domit-negative isoforms which are truncated at the NH2-terminus acting as operant inhibitors of TAp73, TAp63 and wild-type p53, and thus possessing oncogenic potential. Like wt p53, TAp63 and TAp73 isoforms transactivate target genes that activate apoptosis signaling pathways. In an attempt to understand how the CD95 gene is regulated by the p53 family, we investigated the contributions of a p53-responsive element (RE) within the first intron of the CD95 gene as well as three elements within the promoter. The intronic element conferred transcriptional activation by p53, TAp63 and TAp73 and cooperated with the p53-REs in the promoter of the CD95 gene. Cooperation between the p53-REs in the promoter and the intronic p53-binding site resulted in maximal transcriptional activation of the CD95 gene by the p53 family. BACKGROUND: Differential mRNA splicing and alternative promoter usage of the TP73 gene results in the expression of multiple NH2-truncated isoforms that act as oncogenes. Abundant levels of these p73 variants in a variety of human cancers correlated with adverse clinical prognosis and response failure to conventional therapies, underscoring their relevance as marker for disease severity and target for cancer intervention. With respect to an equally important role for amino-truncated p73 splice forms (DeltaTAp73) and DeltaNp73 (summarized as DNp73) in the tumorigenic process, we designed locked nucleic acid (LNA) antisense oligonucleotide (ASO) gapmers against individual species that were complementary to DeltaEx2 and DeltaEx2/3 splice junctions and a region in exon 3B unique for DeltaN' and DeltaN. RESULTS: Treatment of cancer cells with these ASOs resulted in a strong and specific reduction of tumorigenic p73 transcripts and proteins, importantly, without abolishing the wild-type p73 tumor suppressor form as observed with p73-shRNA. The specific antisense oligonucleotides rescued cells from apoptosis inhibition due to overexpression of their corresponding amino-truncated p73 isoform and decreased tumor cell proliferation. Furthermore, ASO-116 against DeltaEx2/3 coupled to magnetic obead polyethyleneimine (MNB/PEI) carriers significantly inhibited maligt melanoma growth, which correlated with a shift in the balance between endogenous TAp73 and DeltaEx2/3 towards apoptotic full-length p73. CONCLUSION: Our study demonstrates the successful development of LNA-ASOs that selectively differentiate between the closely related p73 oncoproteins, and provide new tools to further delineate their biological properties in different human maligcies and for therapeutic cancer targeting. The p53 tumor suppressor is part of a small family of related proteins that includes two other members, p73 and p63. Interest in the p53 family members, their functions and their complex interactions and regulation, has steadily grown over recent years and does not show signs of waning. p73 is a major determit of chemosensitivity in humans, and mutant p53 proteins carrying specific polymorphisms can induce drug resistance by inhibiting TAp73. Cooperation between TA (transactivating, proapoptotic, antiproliferative) and Delta N (truncated, antiapoptotic, pro-proliferative) p73 isoforms and among the three family members guarantees equilibrium between proliferation, differentiation, and cell death, thus creating a harmony that is lost in several human cancers. In this article, we review our current knowledge of the role of p73 in cancer chemosensitivity and the real prospect of therapy targeting this molecule. We also draw attention to the crucial role of specific phosphorylation and acetylation events for p73-induced apoptosis and drug chemosensitivity. Mice with a complete deficiency of p73 have severe neurological and immunological defects due to the absence of all TAp73 and DeltaNp73 isoforms. As part of our ongoing program to distinguish the biological functions of these isoforms, we generated mice that are selectively deficient for the DeltaNp73 isoform. Mice lacking DeltaNp73 (DeltaNp73(-/-) mice) are viable and fertile but display signs of neurodegeneration. Cells from DeltaNp73(-/-) mice are sensitized to DNA-damaging agents and show an increase in p53-dependent apoptosis. When analyzing the DNA damage response (DDR) in DeltaNp73(-/-) cells, we discovered a completely new role for DeltaNp73 in inhibiting the molecular signal emanating from a DNA break to the DDR pathway. We found that DeltaNp73 localizes directly to the site of DNA damage, can interact with the DNA damage sensor protein 53BP1, and inhibits ATM activation and subsequent p53 phosphorylation. This novel finding may explain why human tumors with high levels of DeltaNp73 expression show enhanced resistance to chemotherapy. The p73 gene possesses an extrinsic P1 promoter and an intrinsic P2 promoter, resulting in TAp73 and DeltaNup73 isoforms, respectively. The ultimate effect of p73 in oncogenesis is thought to depend on the apoptotic TA to antiapoptotic DeltaN isoforms' ratio. This study was aimed at identifying novel transcription factors that affect TA isoform synthesis. With the use of bioinformatics tools, in vitro binding assays, and chromatin immunoprecipitation analysis, a region extending -233 to -204 bp upstream of the transcription start site of the human p73 P1 promoter, containing conserved Sp1-binding sites, was characterized. Treatment of cells with Sp1 RNAi and Sp1 inhibitor functionally suppress TAp73 expression, indicating positive regulation of P1 by the Sp1 protein. Notably Sp1 inhibition or knockdown also reduces DeltaNup73 protein levels. Therefore, Sp1 directly regulates TAp73 transcription and affects DeltaNup73 levels in lung cancer. TAp73gamma was shown to be the only TA isoform overexpressed in several lung cancer cell lines and in 26 non-small cell lung cancers, consistent with Sp1 overexpression, thereby questioning the apoptotic role of this specific p73 isoform in lung cancer. BACKGROUND & AIMS: p73 belongs to the p53 family of transcription factors known to regulate cell cycle and apoptosis. The Trp73 gene has two promoters that drive the expression of two major p73 isoform subfamilies: TA and ΔN. In general, TAp73 isoforms show proapoptotic activities, whereas members of the N-terminally truncated (ΔN) p73 subfamily that lack the transactivation domain show antiapoptotic functions. We found that upregulation of ΔNp73 in hepatocellular carcinoma (HCC) correlated with reduced survival. Here, we investigated the molecular mechanisms accounting for the oncogenic role of ΔNp73 in HCC. RESULTS: ΔNp73β can directly interfere with the transcriptional activation function of the TA (containing the transactivation domain) isoforms of the p53 family and consequently inhibit transactivation of proapoptotic target genes. Interference of ΔNp73β with apoptosis-/chemosensitivity takes place at several levels of apoptosis signaling. ΔNp73β negatively regulates the genes encoding for the death receptors CD95, TNF-R1, TRAIL-R2 and TNFRSF18. Furthermore, ΔNp73β represses the genes encoding caspase-2, -3, -6, -8 and -9. Concomitantly, ΔNp73β inhibits apoptosis emanating from mitochondria. CONCLUSIONS: Thus, ΔNp73 expression in HCC selects against both the death receptor and the mitochondrial apoptosis activity of the TA isoforms. Our data suggest that ΔNp73 isoforms repress apoptosis-related genes of the extrinsic and intrinsic apoptosis signaling pathways thereby contributing to chemoresistance. The clinical importance of these data is evidenced by our finding that the ΔNp73ß target gene signature can predict the prognosis of patients suffering from HCC. BACKGROUND: p63 is a member of the p53 transcription factor family. p63 is expressed from two promoters resulting in proteins with opposite functions: the transcriptionally active TAp63 and the domit-negative DeltaNp63. Similar to p53, the TAp63 isoforms induce cell cycle arrest and apoptosis. The DeltaNp63 isoforms are domit-negative variants opposing the activities of p53, TAp63 and TAp73. To avoid unnecessary cell death accompanied by proper response to stress, the expression of the p53 family members must be tightly regulated. NAD(P)H quinone oxidoreductase (NQO1) has recently been shown to interact with and inhibit the degradation of p53. Due to the structural similarities between p53 and p63, we were interested in studying the ability of wild-type and polymorphic, inactive NQO1 to interact with and stabilize p63. We focused on TAp63gamma, as it is the most potent transcription activator and it is expected to have a role in tumor suppression. PRINCIPAL FINDINGS: We show that TAp63gamma can be degraded by the 20S proteasomes. Wild-type but not polymorphic, inactive NQO1 physically interacts with TAp63gamma, stabilizes it and protects it from this degradation. NQO1-mediated TAp63gamma stabilization was especially prominent under stress. Accordingly, we found that downregulation of NQO1 inhibits TAp63gamma-dependant p21 upregulation and TAp63gamma-induced growth arrest stimulated by doxorubicin. CONCLUSIONS/SIGNIFICANCE: Our report is the first to identify this new mechanism demonstrating a physical and functional relationship between NQO1 and the most potent p63 isoform, TAp63gamma. These findings appoint a direct role for NQO1 in the regulation of TAp63gamma expression, especially following stress and may therefore have clinical implications for tumor development and therapy. p73 is a p53-related transcription factor with fundamental roles in development and tumor suppression. Transcription from two different promoters on the p73 gene results in generation of transcriptionally active TAp73 isoforms and domit negative DeltaNp73 isoforms with opposing pro- and anti-apoptotic functions. Therefore, the relative ratio of each isoform is an important determit of the cell fate. Proteasomal degradation of p73 is mediated by polyubiquitination-dependent and -independent processes both of which appear, thus far, to lack selectivity for the TAp73 and DeltaNp73 isoforms. Here, we describe the characterization of another transcriptional target of TAp73; a ring finger domain ubiquitin ligase p73 Induced RING 2 protein (PIR2). Although PIR2 was initially identified a p53-induced gene (p53RFP), low abundance of PIR2 transcript in mouse embryonic fibroblasts of TAp73 KO mice compared with WT mice and comparison of PIR2 mRNA and protein levels following TAp73 or p53 overexpression substantiate TAp73 isoforms as strong inducers of PIR2. Although PIR2 expression was induced by DNA damage, its expression did not alter apoptotic response or cell cycle profile per se. However, coexpression of PIR2 with TAp73 or DeltaNp73 resulted in an increase of the TA/DeltaNp73 ratio, due to preferential degradation of DeltaNp73. Finally, PIR2 was able to relieve the inhibitory effect of DeltaNp73 on TAp73 induced apoptosis following DNA damage. These results suggest that PIR2, by being induced by TAp73 and degrading DeltaNp73, differentially regulates TAp73/DeltaNp73 stability, and, hence, it may offer a therapeutic approach to enhance the chemosensitivity of tumor cells. BACKGROUND: We examined the association of one linked GC/AT polymorphism at p73 with the risk of colorectal cancer. AIM: In this study, we investigated whether this polymorphism was related to the risk of colorectal cancer, and whether there were relationships between the polymorphism and loss of heterozygosity, protein expression, or clinicopathologic variables. MATERIALS AND METHODS: The p73 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism in 150 Tunisian patients with colorectal cancer and in 204 healthy control subjects. Immunohistochemistry was performed on normal mucosa, primary tumor, and metastasis. RESULTS: The frequencies of the genotypes were 52% for wild-type (GC/GC), 31% for heterozygotes (GC/AT), and 17% for variants(AT/AT) in patients, and 54%, 35%, and 11% in controls, respectively. There were no significant differences of the frequencies of the 3 genotypes between the patients and controls (P=0.11). We did not find any relationship of the genotypes with clinicopathologic features of patients. We found that patients with the GC/GC genotype had a significantly more favorable clinical outcome than the patients with the AT variants (AT/AT or GC/AT genotype). There were no significant difference between tumoral immunostaining and p73 polymorphism (P=0.16) but we found that the samples carrying the AT allele showed a tendency to be more stained in tumor. No loss of heterozygosity was observed at p73 locus. Our results suggest that the AT/AT genotype is significantly associated with poor prognosis in colorectal cancer. All these findings suggest that p73 polymorphism analysis may provide useful prognostic information for colorectal cancer patients. We evaluate whether 1,25(OH)(2)D(3) downregulates TP73 variants in colon and breast carcinomas, the role of survivin in this context, and the significance of this network in the clinic. Tumor cells were treated/untreated with 1,25(OH)(2)D(3) and transiently transfected with survivin. Levels of survivin and TP73 variants were evaluated by quantitative RT-PCR and Western blotting. In 75 colon and 60 breast cancer patients, the expressions of survivin and TP73 isoforms were determined. Tumor characteristics were examined in each patient. Survivin protein levels were also evaluated in a subgroup of patients and cell lines. Decrease in survivin and TAp73 transcripts and protein and ΔNp73 mRNA was detected after 1,25(OH)(2)D(3) treatment. Ectopic survivin expression led to an increase in the TAp73, ΔNp73, ΔEx2p73, and ΔEx2-3p73 transcripts. In cancer patients, direct correlations were observed between TP73 variants and survivin levels. 1,25(OH)(2)D(3) negatively regulate survivin and TP73 variants in colon and breast cancer cells. Positive regulation of TP73 isoforms by survivin may exist, which reinforces the possibility that the downregulation of TP73 forms by 1,25(OH)(2)D(3) is survivin-dependent. p73 possesses an extrinsic P1 promoter and an intrinsic P2 promoter controlling the expression of the pro-apoptotic TAp73 isoforms and the anti-apoptotic ΔΝp73 isoforms respectively. In this study, we investigated the DNA methylation status of both promoters as a means of epigenetic transcriptional control of their corresponding isoforms in 102 primary non-small cell lung carcinomas (NSCLCs). We demonstrated that while P1 hypermethylation-associated reduction of TAp73 mRNA levels is relatively infrequent, the P2 hypomethylation-associated over-expression of ΔΝp73 mRNA is a frequent event, particularly among squamous cell carcinomas. P2 hypomethylation strongly correlated with LINE-1 element hypomethylation, indicating that ΔΝp73 over-expression may be a passive consequence of global DNA hypomethylation. The ΔNp63 protein, a product of the TP63 gene that lacks the N-terminal domain, has a critical role in the maintece of self renewal and progenitor capacity in several types of epithelial tissues. ΔNp63 is frequently overexpressed in squamous cell carcinoma (SCC) and in some other epithelial tumours. This overexpression may contribute to tumour progression through domit-negative effects on the transcriptionally active (TA) isoforms of the p53 family (TAp63, TAp73 and p53), as well as through independent mechanisms. However, the molecular basis of ΔNp63 overexpression is not fully understood. Here, we show that the expression of ΔNp63 is regulated by the Wnt/β-catenin pathway in human hepatocellular carcinoma (HCC) and SCC cell lines. This regulation operates in particular through TCF/LEF sites present in the P2 promoter of TP63. In addition, we show that ΔNp63 and β-catenin are frequently coexpressed and accumulated in oesophageal SCC, but not in HCC. These results suggest that activation of the β-catenin pathway may contribute to overexpression of ΔNp63 during tumour progression, in a cell type-specific manner. PURPOSE: Cumulative data support the role of ΔTAp73 variants in tumorigenic processes such as drug resistance. We evaluate the impact of TP73 isoforms and their putative target genes ABCB1, HMGB1, and CASP1 on the survival of colon cancer patients and the correlation between their expressions. EXPERIMENTAL DESIGN: We determined in 77 colon cancer patients the expression of ΔEx2p73, ΔEx2/3p73, ΔNp73, TAp73, ABCB1, HMGB1, and CASP1 by quantitative real-time reverse transcriptase-PCR. Tumor characteristics, disease-free survival, and overall survival (OS) were examined in each patient. Functional experiments were carried out to check whether ectopic expression of ΔNp73 modifies the proliferation, drug resistance, migration, and invasion properties of colon tumor cells and the expression of ABCB1, HMGB1, and CASP1. RESULTS: Positive correlations were observed between the expression levels of ΔTAp73 variants and HMGB1. Furthermore, a trend was observed for ABCB1. Overexpression of ΔEx2/3p73 and ΔNp73 isoforms was significantly associated with advanced stages (P = 0.04 and P = 0.03, respectively) and predicted shortened OS (P = 0.04 and P = 0.05, respectively). High levels of ABCB1 and HMGB1 were associated with shorter OS (P = 0.04 and P = 0.05, respectively). Multivariate analysis showed that, in addition to the tumor stage, ABCB1 and HMGB1 had independent relationships with OS (P = 0.008). Ectopic expression of ΔNp73 was associated with an increase in proliferation and drug resistance. CONCLUSIONS: The positive correlation between ΔTAp73 variants and HMGB1 and ABCB1 expression supports them as TP73 targets. The fact that upregulation of ΔTAp73 isoforms was associated with shortened OS, increase in proliferation, and drug resistance confirms their oncogenic role and plausible value as prognostic markers. ABCB1 and HMGB1, putative ΔTAp73 target genes, strongly predict OS in an independent manner, making clear the importance of studying downstream TP73 targets that could predict the outcome of colon cancer patients better than ΔTAp73 variants themselves do. Studies on oocyte transcriptome are important to understand the biological pathways involved in oogenesis, totipotence and early embryonic development. Moreover, genes regulating physiological pathways in gametes could represent potential candidates for reproductive disorders. In addition to oocyte specific transcription factors, also the members of the p53 family could be etiologically involved due to their biological functions. In fact, their role in the control of cell cycle, apoptosis, and germ-line genome stability is well known. Female reproductive aging is one of the causes of fertility reduction and it is often associated with egg aneuploidy increase. In order to verify the potential involvement of p73 in reproductive aging, we determined its expression in single mature MII oocytes from two groups of women, younger than 35 or older than 38 years, respectively. We found that TAp73 isoforms are down regulated in oocytes from women older than 38 years. We confirmed these data in pools of mouse oocytes. TAp73 down regulation in oocytes from women of advanced reproductive age could explain both the reduction of fertility and the increase of newborns with chromosomal abnormalities. p63 and p73, two p53 family members, play crucial roles in development and tumor suppression. p63 and p73 have multiple isoforms, which have similar or distinct biological functions. Transactivation (TA) isoforms of p63 and p73 have high similarity with p53 and often have biological functions similar to p53. p53 plays an important role in nucleotide excision repair (NER) through transcriptional regulation of target genes involved in NER, including DDB2, XPC and GADD45. To investigate whether TAp63 and TAp73 play a similar role in NER, Saos2 cells with inducible expression of specific isoforms of TAp63 and TAp73, including TAp63α/β/γ and TAp73α/β/γ isoforms, were employed. Overexpression of TAp63γ significantly enhances NER of ultraviolet (UV)-induced DNA damage, including cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts, and enhances cell survival after UV irradiation in Soas2 cells. The enhancement of NER of UV-induced DNA damage by TAp63γ was also confirmed in H1299 cells with overexpression of TAp63γ. Consistently, knockdown of endogenous TAp63 decreases NER of UV-induced DNA damage in H1299 cells. TAp63α/β and TAp73α/β/γ isoforms do not have a clear effect on NER in Saos2 or H1299 cells. TAp63γ overexpression clearly induces the expression of DDB2, XPC and GADD45 at both RNA and protein levels. Furthermore, luciferase reporter assays show that TAp63γ transcriptionally activates DDB2, XPC and GADD45 genes through the regulation of the p53 binding elements in these genes. These results demonstrate that TAp63γ enhances NER to remove UV-induced DNA damage and maintain genomic stability through transcriptional induction of a set of NER proteins, which provides an additional important mechanism that contributes to the function of TAp63 in tumor suppression. p73 is expressed as TA and ΔN isoforms, both of which are implicated in tumor suppression and/or promotion. To address how p73 possesses these opposing functions, we developed three-dimensional culture of MCF10A cells, which undergo cell morphogenesis to form polarized spheroids with hollow lumen similar to normal mammary acini in vivo. Here, we showed that upon knockdown of p73, particularly TAp73 but not ΔNp73, MCF10A cells formed irregular and near-normal acini without hollow lumen in three-dimensional culture. We also found that upon knockdown of p73 or TAp73, but not ΔNp73, MCF10A cells underwent epithelial-to-mesenchymal transition (EMT) via down-regulation of E-cadherin coupled with up-regulation of β-catenin and laminin V. In addition, we found that Snail-1, Slug, and Twist, all of which are known to act as EMT inducers by repressing E-cadherin expression, were increased markedly upon knockdown of p73 and TAp73 but little if any by ΔNp73. Furthermore, we showed that knockdown of p73 or TAp73 in MCF10A cells led to a marked increase in cell proliferation and migration. Together, our data suggest that TAp73 is necessary for maintaining normal cell polarity by suppressing EMT. Apoptin, a protein derived from the chicken anaemia virus, induces cell death in various cancer cells but shows little or no cytotoxicity in normal cells. The mechanism of apoptin-induced cell death is currently unknown but it appears to induce apoptosis independent of p53 status. Here we show that p73, a p53 family member, is important in apoptin-induced apoptosis. In p53 deficient and/or mutated cells, apoptin induced the expression of TAp73 leading to the induction of apoptosis. Knockdown of p73 using siRNA resulted in a significant reduction in apoptin-induced cytotoxicity. The p53 and p73 pro-apoptotic target PUMA plays an important role in apoptin-induced cell death as knockdown of PUMA significantly reduced cell sensitivity to apoptin. Importantly, apoptin expression resulted in a marked increase in TAp73 protein stability. Investigation into the mechanisms of TAp73 stability showed that apoptin induced the expression of the ring finger domain ubiquitin ligase PIR2 which is involved in the degradation of the anti-apoptotic ∆Np73 isoform. Collectively, our results suggest a novel mechanism of apoptin-induced apoptosis through increased TAp73 stability and induction of PIR2 resulting in the degradation of ∆Np73 and activation of pro-apoptotic targets such as PUMA causing cancer cell death. Amyotrophic lateral sclerosis (ALS) is a devastating paralytic disorder caused by dysfunction and degeneration of motor neurons starting in adulthood. Most of our knowledge about the pathophysiological mechanisms of ALS comes from transgenic mice models that emulate a subgroup of familial ALS cases (FALS), with mutations in the gene encoding superoxide dismutase (SOD1). In the more than 15 years since these mice were generated, a large number of abnormal cellular mechanisms underlying motor neuron degeneration have been identified, but to date this effort has led to few improvements in therapy, and no cure. Here, we consider that this surfeit of mechanisms is best interpreted by current insights that suggest a very early initiation of pathology in motor neurons, followed by a diversity of secondary cascades and compensatory mechanisms that mask symptoms for decades, until trauma and/or aging overloads their protective function. This view thus posits that adult-onset ALS is the consequence of processes initiated during early development. In fact, motor neurons in neonatal mutant SOD mice display important alterations in their intrinsic electrical properties, synaptic inputs and morphology that are accompanied by subtle behavioral abnormalities. We consider evidence that human mutant SOD1 protein in neonatal hSOD1(G93A) mice instigates motor neuron degeneration by increasing persistent sodium currents and excitability, in turn altering synaptic circuits that control excessive motor neuron firing and leads to excitotoxicity. We also discuss how therapies that are aimed at suppressing abnormal neuronal activity might effectively mitigate or prevent the onset of irreversible neuronal damage in adulthood. J. Cell. Biochem. 113: 3301-3312, 2012. © 2012 Wiley Periodicals, Inc. p73 is a p53 family transcription factor. Due to the presence in the 5' flanking region of two promoters, there are two N-terminal variants, TAp73, which retains a fully active transactivation domain (TA), and ΔNp73, in which the N terminus is truncated. In addition, extensive 3' splicing gives rise to at least seven distinctive isoforms; TAp73-selective knockout highlights its role as a regulator of cell death, senescence and tumor suppressor. ΔNp73-selective knockout, on the other hand, highlights anti-apoptotic function of ΔNp73 and its involvement in DNA damage response. In this work, we investigated the expression pattern of murine p73 C-terminal isoforms. By using a RT-PCR approach, we were able to detect mRNAs of all the C-terminal isoforms described in humans. We characterized their in vivo expression profile in mouse organs and in different mouse developmental stages. Finally, we investigated p73 C-terminal expression profile following DNA damage, ex vivo after primary cultures treatment and in vivo after systemic administration of cytotoxic compounds. Overall, our study first elucidates spatio-temporal expression of mouse p73 isoforms and provides novel insights on their expression-switch under triggered conditions. P73 is a member of the p53 transcription factors family with a prominent role in neurobiology, affecting brain development as well as controlling neuronal survival. Accordingly, p73 has been identified as key player in many age-related neurodegenerative diseases, such as Alzheimer's disease, neuroAIDS and Niemann-Pick type C disease. Here we investigate possible correlations of p73 with Parkinson disease. Tyrosine hydroxylase is a crucial player in Parkinson disease being the enzyme necessary for dopamine synthesis. In this work we show that levels of tyrosine hydroxylase can be influenced by p73. We also demonstrate that p73 can protect against tyrosine hydroxylase depletion in an in vitro model of Parkinson disease. Histone deacetylases (HDACs) play important roles in fundamental cellular processes, and HDAC inhibitors are emerging as promising cancer therapeutics. p73, a member of the p53 family, plays a critical role in tumor suppression and neural development. Interestingly, p73 produces two classes of proteins with opposing functions: the full-length TAp73 and the N-terminally truncated ΔNp73. In the current study, we sought to characterize the potential regulation of p73 by HDACs and found that histone deacetylase 1 (HDAC1) is a key regulator of TAp73 protein stability. Specifically, we showed that HDAC1 inhibition by HDAC inhibitors or by siRNA shortened the half-life of TAp73 protein and subsequently decreased TAp73 expression under normal and DNA damage-induced conditions. Mechanistically, we found that HDAC1 knockdown resulted in hyperacetylation and inactivation of heat shock protein 90, which disrupted the interaction between heat shock protein 90 and TAp73 and thus promoted the proteasomal degradation of TAp73. Functionally, we found that down-regulation of TAp73 was required for the enhanced cell migration mediated by HDAC1 knockdown. Together, we uncover a novel regulation of TAp73 protein stability by HDAC1-heat shock protein 90 chaperone complex, and our data suggest that TAp73 is a critical downstream mediator of HDAC1-regulated cell migration. BACKGROUND: P73 belongs to the p53 family of cell survival regulators with the corresponding locus Trp73 producing the N-terminally distinct isoforms, TAp73 and DeltaNp73. Recently, two studies have implicated the murine Trp73 in the modulation in phospho-tau accumulation in aged wild type mice and in young mice modeling Alzheimer's disease (AD) suggesting that Trp73, particularly the DeltaNp73 isoform, links the accumulation of amyloid peptides to the creation of neurofibrillary tangles (NFTs). Here, we reevaluated tau pathologies in the same TgCRND8 mouse model as the previous studies. RESULTS: Despite the use of the same animal models, our in vivo studies failed to demonstrate biochemical or histological evidence for misprocessing of tau in young compound Trp73+/- + TgCRND8 mice or in aged Trp73+/- mice analyzed at the ages reported previously, or older. Secondly, we analyzed an additional mouse model where the DeltaNp73 was specifically deleted and confirmed a lack of impact of the DeltaNp73 allele, either in heterozygous or homozygous form, upon tau pathology in aged mice. Lastly, we also examined human TP73 for single nucleotide polymorphisms (SNPs) and/or copy number variants in a meta-analysis of 10 AD genome-wide association datasets. No SNPs reached significance after correction for multiple testing and no duplications/deletions in TP73 were found in 549 cases of AD and 544 non-demented controls. CONCLUSION: Our results fail to support P73 as a contributor to AD pathogenesis. The TP73 gene, a member of the p53 family, due to the use of different promoters and alternative splicing, is transcribed into different isoforms with contrasting attributes and which contribute to its functional diversity. Considerable efforts are made to identify the functional diversity of the p73 splicing variants during tumorigenesis. TAp73α and TAp73β isoforms have been shown to differentially regulate cell cycle progression, differentiation and apoptosis. Interestingly, a particular increase in expression of the TAp73 isoform, in favor of the α splicing variant, has been reported in multiple tumour types. Here, we report a distinctive role for TAp73β isoform in the control of cell migration and invasion. In fact, TAp73β- dependent induction of p57(Kip2) expression accounted for inhibitory effects on the actin cytoskeleton dynamics and thereby cancer cell motility. In contrast, TAp73α is not able to induce p57(Kip2) expression, and exhibits a positive effect on actin cytoskeleton dynamics as well as cell migration and invasion. In conclusion, the inhibitory effect on cell migration and invasion of TAp73β would qualify this distinct p73 isoform as tumor suppressor gene. In contrast, the promoting effect of TAp73α on cell motility and invasion strengthens the potential oncogenic activities of this p73 isoform.

Is the yeast Μac1 transcription factor induced upon copper deficiency?

In Saccharomyces cerevisiae, transcriptional responses to copper deficiency are mediated by the copper-responsive transcription factor Mac1. Ace1 mediates copper-induced gene expression in cells exposed to stressful levels of copper salts, whereas Mac1 activates a subset of genes under copper-deficient conditions.

In Saccharomyces cerevisiae, copper ions regulate gene expression through the two transcriptional activators, Ace1 and Mac1. Ace1 mediates copper-induced gene expression in cells exposed to stressful levels of copper salts, whereas Mac1 activates a subset of genes under copper-deficient conditions. DNA microarray hybridization experiments revealed a limited set of yeast genes differentially expressed under growth conditions of excess copper or copper deficiency. Mac1 activates the expression of six S. cerevisiae genes, including CTR1, CTR3, FRE1, FRE7, YFR055w, and YJL217w. Two of the last three newly identified Mac1 target genes have no known function; the third, YFR055w, is homologous to cystathionine gamma-lyase encoded by CYS3. Several genes that are differentially expressed in cells containing a constitutively active Mac1, designated Mac1(up1), are not direct targets of Mac1. Induction or repression of these genes is likely a secondary effect of cells because of constitutive Mac1 activity. Elevated copper levels induced the expression of the metallothioneins CUP1 and CRS5 and two genes, FET3 and FTR1, in the iron uptake system. Copper-induced FET3 and FTR1 expression arises from an indirect copper effect on cellular iron pools. Copper is an indispensable metal for life. For convenience of genetic manipulation and sharing similar metabolic pathway of metals with mammalian cells, the yeast Saccharomyces cerevisiae is widely used for metal homeostasis studies. Storage and mobilization of copper ions in yeast vacuoles or mammalian lysosomes are important for cells to avoid their toxicity and elevate their utility. Though regulation of other genes involved in copper homeostasis is well understood, the regulation of gene encoding low-affinity copper transporter Ctr2p, which mediates mobilization of vacuolar or lysosomal stored copper ions, is still unclear. In this study, we found that copper depletion can upregulate yeast CTR2 gene transcription while copper overload downregulate it. The copper-depletion induced CTR2 transcription can be abrogated by genetic deletion of copper-sensing transcription factor Mac1p. Though absent of consensus Mac1p binding sequences, CTR2 promoter region is demonstrated to be occupied by Mac1p, according to our results of chromatin immunoprecipitation (ChIP) assay. Overexpression of Mac1p can upregulate CTR2 transcription and partially complement the growth defect of copper-deficient yeast strain. Taken together, our results suggest that Mac1p can activate the expression of vacuolar copper transporter Ctr2p in response to copper deficiency, resulting in yeast resistance to copper starvation. CTR2 encodes a low-affinity copper transporter that mediates the mobilization of vacuolar copper stores in yeast. We previously reported that CTR2 can be upregulated by copper deficiency via copper-sensing transcription factor Mac1p. In the present study, we found that iron depletion also induces the transcription of CTR2. The upregulation of CTR2 induced by iron depletion was abrogated by the genetic deletion of either Mac1p or iron-sensing transcription factor Aft1p. The ablation of either MAC1 or AFT1 also abrogated CTR2 expression induced by copper depletion. Our further study revealed that exogenous Aft1p upregulates CTR2 transcription only in the presence of Mac1p, whereas exogenous Mac1p upregulates CTR2 transcription only in the presence of Aft1p. Exogenous Mac1p and Aft1p form a stable complex and synergistically enhance CTR2 transcription. These data suggest that Aft1p and Mac1p might corporately regulate transcription of CTR2.

What is the mechanism of DNA replication termination in vertebrates?

Eukaryotic DNA replication terminates when replisomes from adjacent replication origins converge. Termination involves local completion of DNA synthesis, decatenation of daughter molecules and replisome disassembly. DNA synthesis does not slow detectably as forks approach each other, and leading strands pass each other unhindered before undergoing ligation to downstream lagging strands. Dissociation of the replicative CMG helicase (comprising CDC45, MCM2-7 and GINS) occurs only after the final ligation step, and is not required for completion of DNA synthesis, strongly suggesting that converging CMGs pass one another and dissociate from double-stranded DNA. This termination mechanism allows rapid completion of DNA synthesis while avoiding premature replisome disassembly.

Which are the different members/isoforms of the Ras oncogenes?

Ras proteins are proto-oncogenes that are frequently mutated in human cancers. Three closely related isoforms, HRAS, KRAS and NRAS, are expressed in all cells and have overlapping but distinctive functions.

Among the wealth of information that we have gathered about Ras in the past decade, the introduction of the concept of space in the field has constituted a major revolution that has enabled many pieces of the Ras puzzle to fall into place. In the early days, it was believed that Ras functioned exclusively at the plasma membrane. Today, we know that within the plasma membrane, the 3 Ras isoforms-H-Ras, K-Ras, and N-Ras-occupy different microdomains and that these isoforms are also present and active in endomembranes. We have also discovered that Ras proteins are not statically associated with these localizations; instead, they traffic dynamically between compartments. And we have learned that at these localizations, Ras is under site-specific regulatory mechanisms, distinctively engaging effector pathways and switching on diverse genetic programs to generate different biological responses. All of these processes are possible in great part due to the posttranslational modifications whereby Ras proteins bind to membranes and to regulatory events such as phosphorylation and ubiquitination that Ras is subject to. As such, space and these control mechanisms act in conjunction to endow Ras signals with an enormous signal variability that makes possible its multiple biological roles. These data have established the concept that the Ras signal, instead of being one single, homogeneous entity, results from the integration of multiple, site-specified subsignals, and Ras has become a paradigm of how space can differentially shape signaling. H-ras, N-ras, and K-ras are canonical ras gene family members frequently activated by point mutation in human cancers and coding for 4 different, highly related protein isoforms (H-Ras, N-Ras, K-Ras4A, and K-Ras4B). Their expression is nearly ubiquitous and broadly conserved across eukaryotic species, although there are quantitative and qualitative differences of expression depending on the tissue and/or developmental stage under consideration. Extensive functional studies have determined during the last quarter century that these Ras gene products are critical components of signaling pathways that control eukaryotic cell proliferation, survival, and differentiation. However, because of their homology and frequent coexpression in various cellular contexts, it remained unclear whether the different Ras proteins play specific or overlapping functional roles in physiological and pathological processes. Initially, their high degree of sequence homology and the observation that all Ras isoforms share common sets of downstream effectors and upstream activators suggested that they were mostly redundant functionally. In contrast, the notion of functional specificity for each of the different Ras isoforms is supported at present by an increasing body of experimental observations, including 1) the fact that different ras isoforms are preferentially mutated in specific types of tumors or developmental disorders; 2) the different transforming potential of transfected ras genes in different cell contexts; 3) the distinct sensitivities exhibited by the various Ras family members for modulation by different GAPs or GEFs; 4) the demonstration that different Ras isoforms follow distinct intracellular processing pathways and localize to different membrane microdomains or subcellular compartments; 5) the different phenotypes displayed by genetically modified animal strains for each of the 3 ras loci; and 6) the specific transcriptional networks controlled by each isoform in different cellular settings. Ras proteins are proto-oncogenes that are frequently mutated in human cancers. Three closely related isoforms, HRAS, KRAS and NRAS, are expressed in all cells and have overlapping but distinctive functions. Recent work has revealed how differences between the Ras isoforms in their trafficking, localization and protein-membrane orientation enable signalling specificity to be determined. We review the various strategies used to characterize compartmentalized Ras localization and signalling. Localization is an important contextual modifier of signalling networks and insights from the Ras system are of widespread relevance for researchers interested in signalling initiated from membranes. All mammalian cells express 3 closely related Ras proteins, termed H-Ras, K-Ras, and N-Ras, that promote oncogenesis when they are mutationally activated at codon 12, 13, or 61. Although there is a high degree of similarity among the isoforms, K-Ras mutations are far more frequently observed in cancer, and each isoform displays preferential coupling to particular cancer types. We examined the mutational spectra of Ras isoforms curated from large-scale tumor profiling and found that each isoform exhibits surprisingly distinctive codon mutation and amino-acid substitution biases. These findings were unexpected given that these mutations occur in regions that share 100% amino-acid sequence identity among the 3 isoforms. Of importance, many of these mutational biases were not due to differences in exposure to mutagens, because the patterns were still evident when compared within specific cancer types. We discuss potential genetic and epigenetic mechanisms, as well as isoform-specific differences in protein structure and signaling, that may promote these distinct mutation patterns and differential coupling to specific cancers. Ras proteins are small GTPase functioning as molecular switches that, in response to particular extracellular signalling, as growth factors, activate a diverse array of intracellular effector cascades regulating cell proliferation, differentiation and apoptosis. Human tumours frequently express Ras proteins (Ha-, Ki-, N-Ras) activated by point mutations which contribute to maligt phenotype, including invasiveness and angiogenesis. Despite the common signalling pathways leading to similar cellular responses, studies clearly demonstrate unique roles of the Ras family members in normal and pathological conditions and the lack of functional redundancy seems to be explainable, at least in part, by the ability of Ras isoforms to localize in different microdomains to plasma membrane and intracellular organelles. This different intracellular compartmentalization could help Ras isoforms to contact different downstream effectors finally leading to different biological outcomes. Interestingly, it has also been shown that Ha- and Ki-Ras exert an opposite role in regulating intracellular redox status. In this regard we suggest that H-Ras specific induction of ROS (reactive oxygen species) production could be one of the main determits of the invasive phenotype which characterize cancer cells harbouring H-Ras mutations. In our hypothesis then, while K-Ras (not able to promote oxidative stress) could mainly contribute to cancer progression and invasiveness through activation of MAPK and PI3K, H-Ras-mediated oxidative stress could play a unique role in modulation of intercellular contacts leading to a loss of cell adhesion and eventually also to a metastatic spread. H-Ras, K-Ras, and N-Ras regulate cellular growth and survival and are often activated by somatic mutation in human tumors. Although oncogenic lesions occur in a single Ras isoform within individual tumors, it is unclear whether the remaining wild-type isoforms play supporting roles in tumor growth. Here, we show that oncogenic and wild-type Ras isoforms play independent and nonredundant roles within the cell. Oncogenic Ras regulates basal effector pathway signaling, whereas wild-type Ras mediates signaling downstream of activated receptor tyrosine kinases (RTK). We show that both are necessary for exponential growth of Ras-mutant cell lines. Furthermore, we show that oncogenic Ras desensitizes signaling from EGF receptor (EGFR). Depletion of oncogenic Ras with siRNA oligonucleotides relieves this negative feedback, leading to the hyperactivation of EGFR and wild-type Ras signaling. Consistent with this model, combining oncogenic Ras depletion with EGFR inhibition potently increases cell death. SIGNIFICANCE: The results of this study highlight a novel role for wild-type Ras signaling in cancer cells harboring oncogenic RAS mutations. Furthermore, these findings reveal that therapeutically targeting oncogenic Ras signaling alone may be ineffective owing to feedback activation of RTKs, and suggest that blocking upstream RTKs in combination with downstream effector pathways may be beneficial in the treatment of Ras-mutant tumors. Ras proteins undergo an incompletely understood trafficking process in the cell. Rasosomes are protein oparticles of 80-100 nm diameter that carry lipidated Ras isoforms (H-Ras and N-Ras) as well as their effectors through the cytoplasm and near the plasma membrane (PM). In this study, we identified the subcellular origin of rasosomes and how they spread Ras proteins through the cell. We found no dependency of rasosome formation on galectins, or on the GDP-/GTP-bound state of Ras. We found that significantly more rasosomes are associated with forms of Ras that are localized to the Golgi, namely N-Ras or the singly palmitoylated H-Ras mutant (C181S). To explore the possibility that rasosome originate from the Golgi, we used photoactivatable (PA)-GFP-H-Ras mutants and showed that rasosomes bud from the Golgi in a two-step mechanism. Newly released rasosomes first move in an energy-dependent directed fashion and then convert to randomly diffusing rasosomes. Dual fluorescence time-lapse imaging revealed the appearance of dually labeled rasosomes, indicating a dynamic exchange of cytoplasmic and PM-associated Ras with rasosome-associated Ras. Finally, higher levels of rasosomes correlate with higher levels of ERK phosphorylation, a key marker of Ras downstream signaling. We suggest that H-Ras and N-Ras proteins exchange with rasosomes that can function as carriers of palmitoylated Ras and its signals. The mutant forms of KRas, NRas and HRas drive the initiation and progression of a number of human cancers, but less is known about the role of WT (wild-type) Ras alleles and isoforms in cancer. We used zinc-finger nucleases targeting HRas and NRas to modify both alleles of these genes in the mutant KRas-driven Hec1A endometrial cancer cell line, which normally expresses WT copies of these genes. The disruption of either WT isoform of Ras compromised growth-factor-dependent signalling through the ERK (extracellular-signal-regulated kinase) pathway. In addition, the disruption of HRas hindered the activation of Akt and subsequent downstream signalling. This was associated with decreased proliferation, increased apoptosis and decreased anchorage-independent growth in the HRas-disrupted cells. However, xenograft tumour growth was not significantly affected by the disruption of either NRas or HRas. As expected, deleting the mutant allele of KRas abolished tumour growth, whereas deletion of the remaining WT copy of KRas increased the tumorigenic properties of these cells; deleting a single copy of either HRas or NRas did not mimic this effect. The present study demonstrates that the WT copies of HRas, NRas and KRas play unique roles in the context of mutant KRas-driven tumours. In addition to their role as oncogenes, Ras GTPases are key regulators of cell function. There is a proven relationship between the signaling pathways of transforming growth factor-β1 (TGF- β1) and Ras GTPases. Each of the Ras isoforms (H, N and K) exhibits specific modulatory activity on different cellular pathways. Our purpose has been to study some of the mechanisms involved in the development of renal fibrosis, assessing the individual role of N-Ras in basal and TGF-β1-mediated extracellular matrix (ECM) synthesis, proliferation, and migration in immortalized N-Ras deficient fibroblasts (N-ras(-/-)). Compared to normal counterparts, fibroblasts deficient for N-Ras exhibited higher basal activity levels of phosphatidylinositol-3-kinase (PI3K)/Akt and MEK/Erk, accompanied by upregulated collagen synthesis and diminished proliferation and migration rates. We found that the absence of N-Ras did not affect TGF-β1-induced proliferation and migration, which required PI3K/Akt but not Erk1/2 activation. Similar effector pathway dependence was found for fibronectin and collagen type I expression. Our results indicate that N-Ras might contribute to renal fibrosis through the down-regulation of ECM synthesis and up-regulation proliferation and migration modulating Akt activation. N-Ras also regulates TGF-β1-induced collagen I and fibronectin expression through Erk-independent pathways. Mutations in Ras isoforms such as K-Ras, N-Ras, and H-Ras contribute to roughly 85, 15, and 1% of human cancers, respectively. Proper membrane targeting of these Ras isoforms, a prerequisite for Ras activity, requires farnesylation or geranylgeranylation at the C-terminal CAAX box. We devised an in vivo screening strategy based on monitoring Ras activation and phenotypic physiological outputs for assaying synthetic Ras function inhibitors (RFI). Ras activity was visualized by the translocation of RBD Raf1 -GFP to activated Ras at the plasma membrane. By using this strategy, we screened one synthetic farnesyl substrate analog (AGOH) along with nine putative inhibitors and found that only m-CN-AGOH inhibited Ras activation. Phenotypic analysis of starving cells could be used to monitor polarization, motility, and the inability of these treated cells to aggregate properly during fruiting body formation. Incorporation of AGOH and m-CN-AGOH to cellular proteins was detected by western blot. These screening assays can be incorporated into a high throughput screening format using Dictyostelium discoideum and automated microscopy to determine effective RFIs. These RFI candidates can then be further tested in mammalian systems.

Which is the subcellular localization of ERAP2?

Endoplasmic reticulum aminopeptidase 2 (ERAP2) is localized to the luminal side of the endoplasmic reticulum.

The placental leucine aminopeptidase (P-LAP), adipocyte-derived leucine aminopeptidase (A-LAP) and leukocyte-derived aminopeptidase (L-RAP) belong to one distinct group of the M1 family of amimopeptidases, which we term the "Oxytocinase subfamily". They share HEXXH(X)18E Zn-binding and GAMEN motifs essential for the enzymatic activities. Intracellular localization is the characteristic feature of the subfamily members. While P-LAP is translocated from intracellular vesicles to plasma membrane in a stimulus-dependent manner, both A-LAP and L-RAP are retained in the endoplasmic reticulum. They contain sequences necessary for the specific localization in the cell. It is getting evident that the subfamily members play important roles in the maintece of homeostasis including maintece of normal pregcy, memory retention, blood pressure regulation and antigen presentation. In this review, current situation of this newly identified subfamily is summarized. The human endoplasmic reticulum aminopeptidase (ERAP) 1 and 2 proteins were initially identified as homologues of human placental leucine aminopeptidase/insulin-regulated aminopeptidase. They are categorized as a unique class of proteases based on their subcellular localization on the luminal side of the endoplasmic reticulum. ERAPs play an important role in the N-terminal processing of the antigenic precursors that are presented on the major histocompatibility complex (MHC) class I molecules. ERAPs are also implicated in the regulation of a wide variety of physiological phenomena and pathogenic conditions. In this review, the current knowledge on ERAPs is summarized. Epithelial cell adhesion molecule (EpCAM) is an epithelial and cancer cell "marker" and there is a cumulative and growing evidence of its signaling role. Its importance has been recognized as part of the breast cancer stem cell phenotype, the tumorigenic breast cancer stem cell is EpCAM(+). In spite of its complex functions in normal cell development and cancer, relatively little is known about EpCAM-interacting proteins. We used breast cancer cell lines and performed EpCAM co-immunoprecipitation followed by mass spectrometry in search for novel potentially interacting proteins. The endoplasmic reticulum aminopeptidase 2 (ERAP2) was found to co-precipitate with EpCAM and to co-localize in the cytoplasm/ER and the plasma membrane. ERAP2 is a proteolytic enzyme set in the endoplasmic reticulum (ER) where it plays a central role in the trimming of peptides for presentation by MHC class I molecules. Expression of EpCAM and ERAP2 in vitro in the presence of dog pancreas rough microsomes (ER vesicles) confirmed N-linked glycosylation, processing in ER and the size of EpCAM. The association between ERAP2 and EpCAM is a unique and novel finding that provides new ideas on EpCAM processing and on how antigen presentation may be regulated in cancer.

Have thyronamines effects on fat tissue?

There is not clear evidence that thyronamines have direct effect on adipose tissue

The thyroid hormone decarboxylation product, 3,5,3'-triiodothyronamine (T3AM), has been shown to inhibit the cAMP production stimulated by isoproterenol in turkey erythrocytes. This adrenergic receptor binding inhibition was not shown by the thyroid hormones nor by tyramine, but was observed for 3,5-diiodotyramine, 3,5-diiodothyronamine, and thyronamine. T3AM also inhibits prolactin secretion in cultured pituitary cells as well as domperidon binding in rat corpora striata membranes. T3AM has no thyromimetic activity at the nuclear level. The molecular structure of T3AM, determined as a borosalicylate salt by X-ray diffraction techniques, is the first report of a decarboxylated thyroid hormone analogue. Sulfotransferases (SULTs) catalyze the sulfation of many endogenous compounds that include monoamine neurotransmitters, such as dopamine (DA), and thyroid hormones (iodothyronines). Decarboxylation of iodothyronines results in formation of thyronamines. In the mouse, thyronamines act rapidly in a nongenomic fashion to initiate hypothermia and decrease cardiac output and heart rate. These effects are attenuated after 1-4 h, and metabolism of thyronamines via sulfation may be a mechanism for termination of thyronamine action. We carried out this study to test thyronamine (T0AM), 3-iodothyronamine (T1AM), 3,5-diiodothyronamine (T2AM), and 3,5,3'-triiodothyronamine (T3AM) as substrates for human liver and cDNA-expressed SULT activities. We characterized several biochemical properties of SULTs using the thyronamines that acted as substrates for SULT activities in a human liver high-speed supernatant pool (n=3). T1AM led to the highest SULT activity. Activities with T0AM and T3AM were 10-fold lower, and there was no detectable activity with T2AM. Thyronamines were then tested as substrates with eight cDNA-expressed SULTs (1A1, 1A2, 1A3, 1C2, 1E1, 2A1, 2B1a, and 2B1b). Expressed SULT1A3 had the greatest activity with T0AM, T1AM, and T3AM, whereas SULT1A1 showed similar activity only with T3AM. Expressed SULT1E1 had low activity with each substrate. T1AM, the most active thyronamine pharmacologically, was associated with the greatest SULT activity of the thyronamines tested in the liver pool and in both the expressed SULT1A3 and SULT1E1 preparations. Our results support the conclusion that sulfation contributes to the metabolism of thyronamines in human liver and that SULT activities may regulate the physiological effects of endogenous thyronamines. A class of thyroid hormone metabolites has dramatic physiological effects on metabolism and heart rate by still-unknown mechanisms of action. A recent study has discovered that thyronamines can inhibit neuronal reuptake of neurotransmitters and prevent the intracellular transport of monoamines for release. This discovery presents a third signaling pathway for thyroid hormone, expands the role that thyroid plays in the central nervous system, and suggests mechanisms of action for the effects of thyronamine-derived neuromodulators. 3-Iodothyronamine is considered as a derivate of thyroid hormone as a result of enzymatic deiodination and decarboxylation. The physiological role of thyronamine (T1AM) is not known. The aim of this study was to analyze the metabolic response to T1AM in the Djungarian hamster Phodopus sungorus. We measured the influence of T1AM (50 mg/kg) on metabolic rate (VO(2)), body temperature (T (b)) and respiratory quotient (RQ) in this species and in BL/6 mice. T1AM treated hamsters as well as the mice showed a rapid decrease in VO(2) and T (b), accompanied by a reduction of RQ from normal values of about approximately 0.9 to approximately 0.70 for several hours. This indicates that carbohydrate utilisation is blocked by the injection of T1AM and that metabolic pathways are rerouted from carbohydrate to lipid utilisation in response to T1AM. This assumption was further supported by the observation that the treatment of T1AM caused ketonuria and a significant loss of body fat. Our results indicate that T1AM has the potential to control the balance between glucose and lipid utilisation in vivo. Trace amine-associated receptors, a novel class of G-protein coupled receptors which respond to trace amines but not to classical biogenic amines, have been found to be expressed in heart. Therefore, we investigated the cardiac effects of the trace amines p-tyramine, beta-phenylethylamine, octopamine, and tryptamine. Isolated rat hearts were perfused in the presence of trace amines, monitoring the hemodynamic variables. In addition, radioligand binding experiments with [3H]-p-tyramine and [125I]-3-iodothyronamine were performed in rat ventricular tissue. Octopamine, beta-phenylethylamine, and tryptamine produced a dose-dependent negative inotropic effect as shown by reduced cardiac output (IC(50)=109 microM, 159 microM, and 242 microM, respectively). In the same preparation a similar effect was produced by thyronamine and 3-iodothyronamine, with IC(50)=94 microM and 27 microM, respectively. The negative inotropic effect of octopamine was confirmed in a papillary muscle preparation. All trace amines except tryptamine increased the heart rate, but this action could be attributed to their sympathomimetic properties, since it was abolished by propranolol. The negative inotropic effect of trace amines was significantly increased by the tyrosine kinase inhibitor genistein. Specific and saturable binding of [(3)H]-p-tyramine and [125I]-3-iodothyronamine was observed in ventricular tissue. While [3H]-p-tyramine was displaced by 3-iodothyronamine, [(125)I]-3-iodothyronamine was not displaced by p-tyramine. In conclusion, trace amines and thyronamines are negative inotropic agents. Their effect appears to be mediated by a subtype of trace amine-associated receptor which is characterized by the rank of potency: 3-iodothyronamine > thyronamine = octopamine = beta-phenylethylamine, while tryptamine and p-tyramine are significantly less active. Thyronamines are naturally occurring, chemical relatives of thyroid hormone. Systemic administration of synthetic 3-iodothyronamine (T(1)AM) and - to a lesser extent - thyronamine (T(0)AM), leads to acute bradycardia, hypothermia, decreased metabolic rate, and hyperglycemia. This profile led us to hypothesize that the central nervous system is among the principal targets of thyronamines. We investigated whether a low dose i.c.v. infusion of synthetic thyronamines recapitulates the changes in glucose metabolism that occur following i.p. thyronamine administration. Plasma glucose, glucoregulatory hormones, and endogenous glucose production (EGP) using stable isotope dilution were monitored in rats before and 120 min after an i.p. (50 mg/kg) or i.c.v. (0.5 mg/kg) bolus infusion of T(1)AM, T(0)AM, or vehicle. To identify the peripheral effects of centrally administered thyronamines, drug-naive rats were also infused intravenously with low dose (0.5 mg/kg) thyronamines. Systemic T(1)AM rapidly increased EGP and plasma glucose, increased plasma glucagon, and corticosterone, but failed to change plasma insulin. Compared with i.p.-administered T(1)AM, a 100-fold lower dose administered centrally induced a more pronounced acute EGP increase and hyperglucagonemia while plasma insulin tended to decrease. Both systemic and central infusions of T(0)AM caused smaller increases in EGP, plasma glucose, and glucagon compared with T(1)AM. Neither T(1)AM nor T(0)AM influenced any of these parameters upon low dose i.v. administration. We conclude that central administration of low-dose thyronamines suffices to induce the acute alterations in glucoregulatory hormones and glucose metabolism following systemic thyronamine infusion. Our data indicate that thyronamines can act centrally to modulate glucose metabolism. The relation between thyrotoxicosis, the clinical syndrome resulting from exposure to excessive thyroid hormone concentrations, and the sympathetic nervous system remains enigmatic. Nevertheless, beta-adrenergic blockers are widely used to manage severe thyrotoxicosis. Recent experiments show that the effects of thyrotoxicosis on hepatic glucose production and insulin sensitivity can be modulated by selective hepatic sympathetic and parasympathetic denervation. Indeed, thyroid hormone stimulates hepatic glucose production via a sympathetic pathway, a novel central pathway for thyroid hormone action. Rodent studies suggest that similar neural routes exist for thyroid hormone analogues (e.g. thyronamines). Further elucidation of central effects of thyroid hormone on autonomic outflow to metabolic organs, including the thyroid and brown adipose tissue, will add to our understanding of hyperthyroidism. Thyronamines (TAMs) are a newly identified class of endogenous signaling compounds. Their structure is identical to that of thyroid hormone and deiodinated thyroid hormone derivatives, except that TAMs do not possess a carboxylate group. Despite some initial publications dating back to the 1950s, TAMs did not develop into an independent area of research until 2004, when they were rediscovered as potential ligands to a class of G protein-coupled receptors called trace-amine associated receptors. Since this discovery, two representatives of TAMs, namely 3-iodothyronamine (3-T(1)AM) and thyronamine (T(0)AM), have been detected in vivo. Intraperitoneal or central injection of 3-T(1)AM or T(0)AM into mice, rats, or Djungarian hamsters caused various prompt effects, such as metabolic depression, hypothermia, negative chronotropy, negative inotropy, hyperglycemia, reduction of the respiratory quotient, ketonuria, and reduction of fat mass. Although their physiological function remains elusive, 3-T(1)AM and T(0)AM have already revealed promising therapeutic potential because they represent the only endogenous compounds inducing hypothermia as a prophylactic or acute treatment of stroke and might thus be expected to cause fewer side effects than synthetic compounds. This review article summarizes the still somewhat scattered data on TAMs obtained both recently and more than 20 yr ago to yield a complete and updated picture of the current state of TAM research. Thyronamines T(0)AM and T(1)AM are naturally occurring decarboxylated thyroid hormone derivatives. Their in vivo administration induces effects opposite to those induced by thyroid hormone, including lowering of body temperature. Since the mitochondrial energy-transduction apparatus is known to be a potential target of thyroid hormone and its derivatives, we investigated the in vitro effects of T(0)AM and T(1)AM on the rates of O(2) consumption and H(2)O(2) release by rat liver mitochondria. Hypothyroid animals were used because of the low levels of endogenous thyronamines. We found that both compounds are able to reduce mitochondrial O(2) consumption and increase H(2)O(2) release. The observed changes could be explained by a partial block, operated by thyronamines, at a site located near the site of action of antimycin A. This hypothesis was confirmed by the observation that thyronamines reduced the activity of Complex III where the site of antimycin action is located. Because thyronamines exerted their effects at concentrations comparable to those found in hepatic tissue, it is conceivable that they can affect in vivo mitochondrial O(2) consumption and H(2)O(2) production acting as modulators of thyroid hormone action.

What are the names of anti-CD52 monoclonal antibody that is used for treatment of multiple sclerosis patients?

Alemtuzumab and Campath-1H are the names of anti-CD52 monoclonal antibody that is used for treatment of multiple sclerosis patients. It has been shown to be effective for treatment naive and treatment resistant multiple sclerosis patients.

The central nervous system lesions of multiple sclerosis (MS) can be detected by magnetic resoce imaging (MRI) and the initial perivascular inflammatory component is distinguished by the presence of gadolinium enhancement. To assess the effect of systemic lymphocyte depletion on disease activity, seven patients with MS received a 10-day intravenous course of the humanised monoclonal antibody CAMPATH-1H (anti-CDw52). With some variations in the protocol, enhanced cerebral MR images were obtained monthly for 3-4 months before and at least 6 months after treatment. 28 enhancing areas were detected on the first series of 7 scans; 51 additional active lesions were identified on 18 scans before treatment; 15 were detected on 20 scans done over the next 3 months, but only 2 active lesions were seen on 23 scans during follow-up beyond 3 months. The difference in lesion incidence rate before and after treatment varied and the rate ratio was significantly reduced in only three patients. Collectively, in a "meta-analysis", the rate ratios were 0.15 [corrected] (95% CI 0.09-0.24) for all seven patients and 0.24 (0.14-0.42; p < 0.001) with exclusion of the patient whose scanning schedule differed. The effect of CAMPATH-1H on disease activity provides direct, but preliminary, evidence that disease activity in MS depends on the availability of circulating lymphocytes and can be prevented by lymphocyte depletion. It is too early to say anything about the clinical results of treatment with this agent. BACKGROUND: Multiple sclerosis results from T-cell-dependent inflammatory demyelination of the central nervous system. Our objective was long-term suppression of inflammation with short-term monoclonal antibody treatment. METHODS: We depleted 95% of circulating lymphocytes in 27 patients with multiple sclerosis by means of a 5-day pulse of the humanised anti-CD52 monoclonal antibody, Campath-1H. Clinical and haematological consequences of T-cell depletion, and in-vitro responses of patients' peripheral-blood mononuclear cells were analysed serially for 18 months after treatment. FINDINGS: Radiological and clinical markers of disease activity were significantly decreased for at least 18 months after treatment. However, a third of patients developed antibodies against the thyrotropin receptor and carbimazole-responsive autoimmune hyperthyroidism. The depleted peripheral lymphocyte pool was reconstituted with cells that had decreased mitogen-induced proliferation and interferon gamma secretion in vitro. INTERPRETATION: Campath-1H causes the immune response to change from the Th1 phenotype, suppressing multiple sclerosis disease activity, but permitting the generation of antibody-mediated thyroid autoimmunity. Campath 1-H (Alemtuzumab) is a humanised monoclonal antibody which targets the CD52 antigen, a low molecular weight glycoprotein present on the surface of most lymphocyte lineages, causing complement mediated lysis and rapid and prolonged T lymphocyte depletion. Following encouraging initial data from other centres we report our open label experience of using Campath 1-H as a treatment in aggressive relapsing multiple sclerosis in a consecutive series of 39 highly selected patients treated across three regional centres and followed for a mean of 1.89 years. The mean annualised relapse rate fell from 2.48 pre treatment to 0.19 post treatment with 29% of documented relapses observed in the 12 weeks following initial infusion. Mean change in EDSS was -0.36 overall and -0.15 in those patients completing > or =1 year of follow- up. Eighty-three per cent of patients had stable or improved disability following treatment. Infusion related side effects were common including rash, headache and pyrexia but were usually mild and self limiting. Transient worsening of pre-existing neurological deficits during infusion was observed in 3 patients. 12 patients developed biochemical evidence of autoimmune dysfunction, 2 patients developed thyroid disease and 1 patient autoimmune skin disease. We conclude that relapse rates fall following Campath 1-H. Whilst side effects were common these were normally self limiting or easily managed, suggesting Campath 1-H may be of use in the treatment of very active relapsing remitting multiple sclerosis. BACKGROUND: Alemtuzumab, a humanized monoclonal antibody that targets CD52 on lymphocytes and monocytes, may be an effective treatment for early multiple sclerosis. METHODS: In this phase 2, randomized, blinded trial involving previously untreated, early, relapsing-remitting multiple sclerosis, we assigned 334 patients with scores of 3.0 or less on the Expanded Disability Status Scale and a disease duration of 3 years or less to receive either subcutaneous interferon beta-1a (at a dose of 44 microg) three times per week or annual intravenous cycles of alemtuzumab (at a dose of either 12 mg or 24 mg per day) for 36 months. In September 2005, alemtuzumab therapy was suspended after immune thrombocytopenic purpura developed in three patients, one of whom died. Treatment with interferon beta-1a continued throughout the study. RESULTS: Alemtuzumab significantly reduced the rate of sustained accumulation of disability, as compared with interferon beta-1a (9.0% vs. 26.2%; hazard ratio, 0.29; 95% confidence interval [CI], 0.16 to 0.54; P<0.001) and the annualized rate of relapse (0.10 vs. 0.36; hazard ratio, 0.26; 95% CI, 0.16 to 0.41; P<0.001). The mean disability score on a 10-point scale improved by 0.39 point in the alemtuzumab group and worsened by 0.38 point in the interferon beta-1a group (P<0.001). In the alemtuzumab group, the lesion burden (as seen on T(2)-weighted magnetic resoce imaging) was reduced, as compared with that in the interferon beta-1a group (P=0.005). From month 12 to month 36, brain volume (as seen on T(1)-weighted magnetic resoce imaging) increased in the alemtuzumab group but decreased in the interferon beta-1a group (P=0.02). Adverse events in the alemtuzumab group, as compared with the interferon beta-1a group, included autoimmunity (thyroid disorders [23% vs. 3%] and immune thrombocytopenic purpura [3% vs. 1%]) and infections (66% vs. 47%). There were no significant differences in outcomes between the 12-mg dose and the 24-mg dose of alemtuzumab. CONCLUSIONS: In patients with early, relapsing-remitting multiple sclerosis, alemtuzumab was more effective than interferon beta-1a but was associated with autoimmunity, most seriously manifesting as immune thrombocytopenic purpura. The study was not powered to identify uncommon adverse events. (ClinicalTrials.gov number, NCT00050778.) Monoclonal antibodies are of growing interest as treatment options for immune-mediated diseases in neurology. As our knowledge of immunological principals increases, we learn to modulate specifically mechanisms of pathogenesis by the use of monoclonal antibodies. It is clearly desirable to improve efficacy in disease treatment without increasing toxicity by using drugs with more specific modes of action. Natalizumab was the first monoclonal antibody approved in the field of neurology for treatment of relapsing remitting multiple sclerosis (MS). Several other monoclonal antibodies are currently under investigation. Alemtuzumab, a monoclonal antibody targeting CD52, is a highly promising agent currently being studied in two phase III clinical trials. In this review, data from the recently published phase II clinical trial in the treatment of early relapsing remitting MS is summarized and analyzed in light of the development of alemtuzumab for MS and its potential role in treating this disease is discussed. Alemtuzumab is a humanized monoclonal antibody against CD52, an antigen found on the surface of normal and maligt lymphocytes. It is approved for the treatment of B-cell chronic lymphocytic leukaemia and is undergoing Phase III clinical trials for the treatment of multiple sclerosis. The exact mechanism by which alemtuzumab mediates its biological effects in vivo is not clearly defined and mechanism of action studies have been hampered by the lack of cross-reactivity between human and mouse CD52. To address this issue, a transgenic mouse expressing human CD52 (hCD52) was created. Transgenic mice did not display any phenotypic abnormalities and were able to mount normal immune responses. The tissue distribution of hCD52 and the level of expression by various immune cell populations were comparable to those seen in humans. Treatment with alemtuzumab replicated the transient increase in serum cytokines and depletion of peripheral blood lymphocytes observed in humans. Lymphocyte depletion was not as profound in lymphoid organs, providing a possible explanation for the relatively low incidence of infection in alemtuzumab-treated patients. Interestingly, both lymphocyte depletion and cytokine induction by alemtuzumab were largely independent of complement and appeared to be mediated by neutrophils and natural killer cells because removal of these populations with antibodies to Gr-1 or asialo-GM-1, respectively, strongly inhibited the activity of alemtuzumab whereas removal of complement by treatment with cobra venom factor had no impact. The hCD52 transgenic mouse appears to be a useful model and has provided evidence for the previously uncharacterized involvement of neutrophils in the activity of alemtuzumab. Alemtuzumab, formally known as Campath-1H, is a humanized monoclonal antibody directed against CD52, a protein on the surface of lymphocytes and monocytes with unknown function. A single dose of alemtuzumab leads to a rapid, profound and prolonged lymphopenia. A Phase II trial has shown that alemtuzumab reduces the risk of relapse and accumulation of disability by over 70% compared with interferon beta in patients with early relapsing-remitting multiple sclerosis (MS). Alemtuzumab has been used in Cambridge as an experimental treatment for MS since 1991. In this review we summarize our experience; describing how this prototypical, "bench-to-bedside" therapy continues to inform basic science, revealing aspects of the pathogenesis of MS and lymphopeniaassociated autoimmunity. Multiple sclerosis (MS) is considered to be an autoimmune disease leading to inflammatory demyelination and axonal damage in the central nervous system (CNS). Current treatments involve non-specific immunosuppression and immunomodulation. The development of monoclonal antibodies for therapeutic use allows targeting of specific immune mechanisms. Natalizumab, a monoclonal antibody directed against alpha4beta1 integrin that plays a crucial role in the transmigration of immune cells across the blood-brain-barrier, has been licensed for relapsing-remitting (RR) MS in 2006. Rituximab, directed against CD20 expressed on pre B-cells and B-cells has been tested successfully in a phase II trial and suggests that several B-cell dependent mechanisms may be relevant to the mode of action. Alemtuzumab, targeting CD52 expressed on T-cells, B-cells, monocytes and macrophages, has also shown to be effective in early RRMS and phase III trials are currently ongoing. Daclizumab binds to CD25, the alpha chain of the interleukin (IL)-2 receptor, and is also being tested for RRMS. Beside the clinical data the results from these clinical trials give also new insights into the pathogenesis of MS. We critically discuss the potential but also the pitfalls and potential hazards of these new therapeutic strategies. Multiple sclerosis (MS) is the most common disabling neurological disease in young adults characterized by recurrent relapses and / or progression that are attributable to multifocal inflammation, demyelination and axonal pathology within the central nervous system. Currently approved disease-modifying treatments achieve their effects primarily by blocking the proinflammatory response in a nonspecific manner. Their limited clinical efficacy urges a more differentiated and specific therapeutic approach. Advances in understanding the pathophysiology of MS and appreciation of the contribution of neurodegenerative processes to disease pathology have led to promising therapeutic approaches at different points along the MS disease pathway: (i) monoclonal antibody therapy has provided the opportunity to rationally direct the therapeutic intervention by specifically targeting mechanisms of the immune system such as CD52 (alemtuzumab), CD25 (daclizumab), VLA-4 (natalizumab) and CD20 (rituximab); (ii) novel oral immunomodulating agents have shown to prevent lymphocyte recirculation from lymphoid organs such as fingolimod (FTY720); (iii) blocking of intracellular signaling cascades or ion channels at the cell-surface can protect axons from degeneration and restore axonal function in experimental settings; (iv) neuroprotective agents and stem cell therapy are able to promote remyelination and axonal regeneration in vitro. Despite the tremendous efforts undertaken, a better understanding of the sequential evolution of the MS lesion and the development of clinical surrogate markers, which allow to define subsets of patients with different forms of underlying pathogenesis, is necessary. This will pave the way for an optimized treatment approach, which will likely need both to target inflammation and to focus on promotion of neuroprotection and repair. Alemtuzumab is a humanized monoclonal antibody targeting CD52, a broadly expressed cell surface molecule on immune cells. Application results in a rapid and long-lasting removal of lymphocyte populations from the circulation. Alemtuzumab-treatment of MS patients with relapsing-remitting forms of the disease significantly reduced the risk of relapse and accumulation of disability compared to interferon β-1a treatment in a phase II trial. Interestingly, further analysis together with parallel experimental studies suggested that alemtuzumab not only reduces disease activity due to its immune cell-depleting effect, but also confers neuroprotective effects, presumably by inducing production of neurotrophic factors in autoreactive T cells. However, alemtuzumab-treated MS patients experienced increased rates of novel autoimmunity and a slight increase in infections, demonstrating that alemtuzumab-mediated skewing of the immune cell compartment has a broad influence on immune functions. This review discusses the current concepts about the underlying mechanisms causing these altered immune responses in alemtuzumab-treated MS patients. BACKGROUND: Alemtuzumab (CD52-specific humanized monoclonal antibody) was found to be an effective therapy for treatment-naive patients with relapsing-remitting multiple sclerosis. OBJECTIVE: Evaluate alemtuzumab's effects in patients with treatment-refractory relapsing-remitting multiple sclerosis. METHODS: Forty-five relapsing-remitting multiple sclerosis patients who experienced ≥2 relapses during 2 years prior to the study entry whilst receiving interferon therapy were administered 24 mg i.v. alemtuzumab/day for 5 days at baseline and 3 days 12 months later. Patients received premedication with 1 g i.v. methylprednisolone on days 1-3 at both times. RESULTS: After 2-year follow-up, the annualized relapse rate was reduced by 94% compared to pre-treatment levels, from 1.6 (2 years prior to treatment) to 0.17 for the 2 years following (P<0.0001). Moreover, 86% of patients showed stable or improved scores on the Expanded Disability Status Scale, and only 1 experienced an increase in disability lasting ≥6 months. The majority (70-88%) showed stable or improved leg, arm and cognitive function as measured by the Multiple Sclerosis Functional Composite. Serious adverse events observed in single patients were transient neutropenia and pneumonia, pulmonary emboli and deep vein thrombosis. Five patients developed clinical thyroid disorders but no opportunistic infections or cases of immune thrombocytopenic purpura were observed. CONCLUSIONS: Alemtuzumab effectively reduced relapse rates and improved clinical scores in patients with active relapsing-remitting multiple sclerosis not controlled by interferon therapy. BACKGROUND: Alemtuzumab is a lymphocyte depleting monoclonal antibody that has demonstrated superior efficacy over interferon β-1a for relapsing-remitting multiple sclerosis (MS), and is currently under investigation in phase 3 trials. One unresolved issue is the duration and significance of the lymphopenia induced. The long term effects on lymphocyte reconstitution of a single course, and the consequences that this has on disability, morbidity, mortality and autoimmunity, were examined. METHODS: The lymphocyte reconstitution (n=36; 384 person years) and crude safety data (n=37; 447 person years) are reported for the first patients with progressive MS to receive alemtuzumab (1991-1997). Reconstitution time was expressed as a geometric mean or, when a non-negligible number of individuals failed to recover, as a median using survival analysis. RESULTS: Geometric mean recovery time (GMRT) of total lymphocyte counts to the lower limit of the normal range (LLN; ≥1.0×10(9) cells/l) was 12.7 months (95% CI 8.8 to 18.2 months). For B cells, GMRT to LLN (≥0.1×10(9)/l) was 7.1 months (95% CI 5.3 to 9.5); median recovery times for CD8 (LLN ≥0.2×10(9) cells/l) and CD4 lymphocytes (LLN ≥0.4×10(9) cells/l) were 20 months and 35 months, respectively. However, CD8 and CD4 counts recovered to baseline levels in only 30% and 21% of patients, respectively. No infective safety concerns arose during 447 person years of follow-up. CONCLUSIONS: Lymphocyte counts recovered to LLN after a single course of alemtuzumab in approximately 8 months (B cells) and 3 years (T cell subsets), but usually did not recover to baseline values. However, this long lasting lymphopenia in patients with a previously normal immune system was not associated with an increased risk of serious opportunistic infection. Recent years have broadened the spectrum of therapeutic strategies and specific agents for treatment of multiple sclerosis (MS). While immune-modulating drugs remain the first-line agents for MS predomitly due to their benign safety profile, our growing understanding of key processes in initiation and progression of MS has pioneered development of new agents with specific targets. One concept of these novel drugs is to hamper migration of immune cells towards the affected central nervous system (CNS). The first oral drug approved for MS therapy, fingolimod inhibits egress of lymphocytes from lymph nodes; the monoclonal antibody natalizumab prevents inflammatory CNS infiltration by blocking required adhesion molecules. The second concept is to deplete T cells and/or B cells from the peripheral circulation using highly specific monoclonal antibodies such as alemtuzumab (anti-CD52) or rituximab/ocrelizumab (anti-CD20). All of these novel, highly effective agents are a substantial improvement in our therapeutic armamentarium; however, they have in common to potentially lower the abundance of immune cells within the CNS, thereby collaterally affecting immune surveillance within this well-controlled compartment. In this review, we aim to critically evaluate the risk/benefit ratio of therapeutic strategies in treatment of MS with a specific focus on infectious neurological side effects. BACKGROUND: The anti-CD52 monoclonal antibody alemtuzumab reduces disease activity in previously untreated patients with relapsing-remitting multiple sclerosis. We aimed to assess efficacy and safety of alemtuzumab compared with interferon beta 1a in patients who have relapsed despite first-line treatment. METHODS: In our 2 year, rater-masked, randomised controlled phase 3 trial, we enrolled adults aged 18-55 years with relapsing-remitting multiple sclerosis and at least one relapse on interferon beta or glatiramer. Eligible participants were randomly allocated in a 1:2:2 ratio by an interactive voice response system, stratified by site, to receive subcutaneous interferon beta 1a 44 μg, intravenous alemtuzumab 12 mg per day, or intravenous alemtuzumab 24 mg per day. Interferon beta 1a was given three-times per week and alemtuzumab was given once per day for 5 days at baseline and for 3 days at 12 months. The 24 mg per day group was discontinued to aid recruitment, but data are included for safety assessments. Coprimary endpoints were relapse rate and time to 6 month sustained accumulation of disability, comparing alemtuzumab 12 mg and interferon beta 1a in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT00548405. FINDINGS: 202 (87%) of 231 patients randomly allocated interferon beta 1a and 426 (98%) of 436 patients randomly allocated alemtuzumab 12 mg were included in the primary analyses. 104 (51%) patients in the interferon beta 1a group relapsed (201 events) compared with 147 (35%) patients in the alemtuzumab group (236 events; rate ratio 0·51 [95% CI 0·39-0·65]; p<0·0001), corresponding to a 49·4% improvement with alemtuzumab. 94 (47%) patients in the interferon beta 1a group were relapse-free at 2 years compared with 278 (65%) patients in the alemtuzumab group (p<0·0001). 40 (20%) patients in the interferon beta 1a group had sustained accumulation of disability compared with 54 (13%) in the alemtuzumab group (hazard ratio 0·58 [95% CI 0·38-0·87]; p=0·008), corresponding to a 42% improvement in the alemtuzumab group. For 435 patients allocated alemtuzumab 12 mg, 393 (90%) had infusion-associated reactions, 334 (77%) had infections (compared with 134 [66%] of 202 patients in the interferon beta 1a group) that were mostly mild-moderate with none fatal, 69 (16%) had thyroid disorders, and three (1%) had immune thrombocytopenia. INTERPRETATION: For patients with first-line treatment-refractory relapsing-remitting multiple sclerosis, alemtuzumab could be used to reduce relapse rates and sustained accumulation of disability. Suitable risk management strategies allow for early identification of alemtuzumab's main adverse effect of secondary autoimmunity. FUNDING: Genzyme (Sanofi) and Bayer Schering Pharma. BACKGROUND: The anti-CD52 monoclonal antibody alemtuzumab reduced disease activity in a phase 2 trial of previously untreated patients with relapsing-remitting multiple sclerosis. We aimed to assess efficacy and safety of first-line alemtuzumab compared with interferon beta 1a in a phase 3 trial. METHODS: In our 2 year, rater-masked, randomised controlled phase 3 trial, we enrolled adults aged 18-50 years with previously untreated relapsing-remitting multiple sclerosis. Eligible participants were randomly allocated in a 2:1 ratio by an interactive voice response system, stratified by site, to receive intravenous alemtuzumab 12 mg per day or subcutaneous interferon beta 1a 44 μg. Interferon beta 1a was given three-times per week and alemtuzumab was given once per day for 5 days at baseline and once per day for 3 days at 12 months. Coprimary endpoints were relapse rate and time to 6 month sustained accumulation of disability in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT00530348. FINDINGS: 187 (96%) of 195 patients randomly allocated interferon beta 1a and 376 (97%) of 386 patients randomly allocated alemtuzumab were included in the primary analyses. 75 (40%) patients in the interferon beta 1a group relapsed (122 events) compared with 82 (22%) patients in the alemtuzumab group (119 events; rate ratio 0·45 [95% CI 0·32-0·63]; p<0.0001), corresponding to a 54·9% improvement with alemtuzumab. Based on Kaplan-Meier estimates, 59% of patients in the interferon beta 1a group were relapse-free at 2 years compared with 78% of patients in the alemtuzumab group (p<0·0001). 20 (11%) of patients in the interferon beta 1a group had sustained accumulation of disability compared with 30 (8%) in the alemtuzumab group (hazard ratio 0·70 [95% CI 0·40-1·23]; p=0·22). 338 (90%) of patients in the alemtuzumab group had infusion-associated reactions; 12 (3%) of which were regarded as serious. Infections, predomitly of mild or moderate severity, occurred in 253 (67%) patients treated with alemtuzumab versus 85 (45%) patients treated with interferon beta 1a. 62 (16%) patients treated with alemtuzumab had herpes infections (predomitly cutaneous) compared with three (2%) patients treated with interferon beta 1a. By 24 months, 68 (18%) patients in the alemtuzumab group had thyroid-associated adverse events compared with 12 (6%) in the interferon beta 1a group, and three (1%) had immune thrombocytopenia compared with none in the interferon beta 1a group. Two patients in the alemtuzumab group developed thyroid papillary carcinoma. INTERPRETATION: Alemtuzumab's consistent safety profile and benefit in terms of reductions of relapse support its use for patients with previously untreated relapsing-remitting multiple sclerosis; however, benefit in terms of disability endpoints noted in previous trials was not observed here. FUNDING: Genzyme (Sanofi) and Bayer Schering Pharma. Alemtuzumab (previously known as Campath(®)) is a humanized monoclonal antibody directed against the CD52 antigen on mature lymphocytes that results in lymphopenia and subsequent modification of the immune repertoire. Here we explore evidence for its efficacy and safety in relapsing-remitting multiple sclerosis. One Phase II and two Phase III trials of alemtuzumab versus active comparator (interferon beta-1a) have been reported. Two of these rater-blinded randomized studies assessed clinical and radiological outcomes in treatment-naïve patients; one explored patients who had relapsed despite first-line therapy. Compared to interferon beta-1a, alemtuzumab reduced the relapse rate by 49%-74% (P < 0.0001), and in two studies it reduced the risk of sustained disability accumulation by 42%-71% (P < 0.01). In one study (Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis; CARE-MS1), there was no significant difference compared to interferon, perhaps reflecting the surprisingly low frequency of disability events in the comparator group. After alemtuzumab, the Expanded Disability Status Scale score improved by 0.14-1.2 points, culminating in a net advantage with alemtuzumab of 0.41-0.77 points over interferon in the CAMMS223 and CARE-MS2 trials (both P < 0.001). Radiological markers of new lesion formation and brain atrophy following alemtuzumab were significantly improved when compared to interferon in all studies. Adverse events were more common following alemtuzumab than interferon beta-1a (7.2-8.66 versus 4.9-5.7 events per person-year). While infusion reactions are the most common, autoimmunity is the most concerning; within Phase III studies, thyroid disorders (17%-18% versus 5%-6%) and immune thrombocytopenic purpura (1% versus 0%) were reported in patients taking alemtuzumab and interferon beta-1a, respectively. All patients responded to conventional therapy. One patient taking alemtuzumab in the Phase II study suffered a fatal intracranial hemorrhage following immune thrombocytopenic purpura, heralding assiduous monitoring of all patients thereafter. Alemtuzumab has been submitted for licensing in relapsing-remitting multiple sclerosis in the United States and Europe. Alemtuzumab was first used in multiple sclerosis in 1991. It is a monoclonal antibody which is directed against CD52, a protein of unknown function on lymphocytes. Alemtuzumab causes a lymphopenia, following which homeostatic reconstitution leads to prolonged alteration of the immune repertoire. This reduces the risk of relapse and disability accumulation in multiple sclerosis; it is the only drug to show superiority over interferon β-1a in disability outcomes in a monotherapy phase III trial. It should be used with a parallel risk management programme to identify the principal adverse effects of alemtuzumab, especially secondary autoimmunity months or years later, mainly against the thyroid but also immune thrombocytopenia. This review charts the development of alemtuzumab as a drug for multiple sclerosis and summarizes the latest clinical trial data. Alemtuzumab is a monoclonal antibody against the CD52 antigen present at high levels on the surface of lymphocytes. While treatment of multiple sclerosis patients with alemtuzumab results in marked depletion of lymphocytes from the circulation, it has not been associated with a high incidence of serious infections. In a human CD52 transgenic mouse, alemtuzumab treatment showed minimal impact on the number and function of innate immune cells. A transient decrease in primary adaptive immune responses was observed post-alemtuzumab but there was little effect on memory responses. These results potentially help explain the level of immunocompetence observed in alemtuzumab-treated MS patients. CONTEXT: Alemtuzumab, an anti-CD52 monoclonal antibody, increased the risk of thyroid dysfunction in CAMMS223, a phase 2 trial in relapsing-remitting multiple sclerosis. OBJECTIVE: The objective of the study was a detailed description of thyroid dysfunction in CAMMS223. DESIGN: Relapsing-remitting multiple sclerosis patients (n=334) were randomized 1:1:1 to 44 μg sc interferon-β-1a (SC IFNB-1a, Rebif) or annual courses of 12 or 24 mg iv alemtuzumab. Thyroid function tests (TSH, free T3, free T4) and thyrotropin-binding inhibitory immunoglobulin (TBII) were assessed at screening, month 1, and quarterly thereafter; antithyroid peroxidase antibodies were assessed at screening and every 6 months. Thyroid dysfunction episodes were categorized post hoc by an endocrinologist. RESULTS: During a median follow-up of 57.3 months, 34% of alemtuzumab and 6.5% of SC IFNB-1a patients had thyroid dysfunction (P<.0001). Ten percent of alemtuzumab and 3% of SC IFNB-1a patients had more than one episode of thyroid dysfunction. With alemtuzumab, Graves' hyperthyroidism occurred in 22%, hypothyroidism in 7%, and subacute thyroiditis in 4%. Of patients with overt Graves' hyperthyroidism, 23% spontaneously became euthyroid and an additional 15% spontaneously developed hypothyroidism. Of patients with overt hypothyroidism, 74% were TBII positive. The annual incidence of a first episode of thyroid dysfunction increased each year through year 3 and then decreased each subsequent study year. CONCLUSIONS: Thyroid dysfunction was more common with alemtuzumab than with SC IFNB-1a. There were few serious episodes. Regular monitoring facilitated early detection. Unique features of this population included high prevalence of Graves' hyperthyroidism, multiple episodes of thyroid dysfunction in individual patients, spontaneous hypothyroidism after overt Graves' hyperthyroidism, and a high prevalence of TBII-positive overt hypothyroidism. Alemtuzumab (anti-CD52 mAb) provides long-lasting disease activity suppression in relapsing-remitting multiple sclerosis (RRMS). The objective of this study was to characterize the immunological reconstitution of T cell subsets and its contribution to the prolonged RRMS suppression following alemtuzumab-induced lymphocyte depletion. The study was performed on blood samples from RRMS patients enrolled in the CARE-MS II clinical trial, which was recently completed and led to the submission of alemtuzumab for U.S. Food and Drug Administration approval as a treatment for RRMS. Alemtuzumab-treated patients exhibited a nearly complete depletion of circulating CD4(+) lymphocytes at day 7. During the immunological reconstitution, CD4(+)CD25(+)CD127(low) regulatory T cells preferentially expanded within the CD4(+) lymphocytes, reaching their peak expansion at month 1. The increase in the percentage of TGF-β1-, IL-10-, and IL-4-producing CD4(+) cells reached a maximum at month 3, whereas a significant decrease in the percentages of Th1 and Th17 cells was detected at months 12 and 24 in comparison with the baseline. A gradual increase in serum IL-7 and IL-4 and a decrease in IL-17A, IL-17F, IL-21, IL-22, and IFN-γ levels were detected following treatment. In vitro studies have demonstrated that IL-7 induced an expansion of CD4(+)CD25(+)CD127(low) regulatory T cells and a decrease in the percentages of Th17 and Th1 cells. In conclusion, our results indicate that differential reconstitution of T cell subsets and selectively delayed CD4(+) T cell repopulation following alemtuzumab-induced lymphopenia may contribute to its long-lasting suppression of disease activity. INTRODUCTION: Alemtuzumab is a humanized IgG1 kappa monoclonal antibody approved for treatment of B-cell chronic lymphocytic leukemia. This cytolytic antibody is directed against CD52 and depletes lymphocytes, with monocytes, macrophages, natural killer cells and a subpopulation of granulocytes being affected to a much lesser degree. Alemtuzumab is currently under review to treat relapsing multiple sclerosis (MS) in the United States, based on positive Phase II and Phase III trials in both treatment-naïve and treated relapsing MS patients. There was excellent efficacy in suppressing both clinical and neuroimaging disease activities. In these trials, the comparator arm was not placebo, but high dose frequently dosed subcutaneous interferon beta 1a. Alemtuzumab has recently been approved by the European authorities for active relapsing MS, in essence as a first-line agent. It produces long-standing effects, consistent with an induction agent. Efficacy will have to be weighed against risk of adverse effects, which include autoimmune disorders and infection. Alemtuzumab joins an increasingly crowded market, and will add to the complexity of treating MS. AREAS COVERED: This review will discuss alemtuzumab as a therapy for MS, reviewing PubMed for clinical trials, publications and presentations at international meetings. It will focus on a United States market perspective. EXPERT OPINION: Alemtuzumab offers induction strategy for very active relapsing MS patients who have failed conventional therapy, and possibly selected treatment-naive patients. Alemtuzumab use is likely to be restricted to specialized MS centers, with long-term monitoring to determine the true risk for adverse effects.

Is there a package in R/bioconductor for classification of alternative splicing?

Yes. SpliceR is an R package for classification of alternative splicing and prediction of coding potential from RNA-seq data.

BACKGROUND: RNA-seq data is currently underutilized, in part because it is difficult to predict the functional impact of alternate transcription events. Recent software improvements in full-length transcript deconvolution prompted us to develop spliceR, an R package for classification of alternative splicing and prediction of coding potential. RESULTS: spliceR uses the full-length transcript output from RNA-seq assemblers to detect single or multiple exon skipping, alternative donor and acceptor sites, intron retention, alternative first or last exon usage, and mutually exclusive exon events. For each of these events spliceR also annotates the genomic coordinates of the differentially spliced elements, facilitating downstream sequence analysis. For each transcript isoform fraction values are calculated to identify transcript switching between conditions. Lastly, spliceR predicts the coding potential, as well as the potential nonsense mediated decay (NMD) sensitivity of each transcript. CONCLUSIONS: spliceR is an easy-to-use tool that extends the usability of RNA-seq and assembly technologies by allowing greater depth of annotation of RNA-seq data. spliceR is implemented as an R package and is freely available from the Bioconductor repository ( http://www.bioconductor.org/packages/2.13/bioc/html/spliceR.html).

Which brain structures have been investigated as potential targets for deep brain stimulation of patients suffering from major depression?

Subgenual cingulate gyrus, the anterior limb of the capsula interna, nucleus accumbens, medial forebrain bundle, habenula, and caudate nucleus have been investigated as potential targeted for the deep brain stimulation of patients suffering from major depression.

Obsessive-compulsive disorder (OCD) is an anxiety disorder associated with recurrent intrusive thoughts and repetitive behaviors. Although conventional pharmacological and/or psychological treatments are well established and effective in treating OCD, symptoms remain unchanged in up to 30% of patients. Deep brain stimulation (DBS) of the anterior limb of the internal capsule has recently been proposed as a possible therapeutic alternative in treatment-resistant OCD. In the present study, the authors tested the hypothesis that DBS of the ventral caudate nucleus might be effective in a patient with intractable severe OCD and concomitant major depression. Psychiatric assessment included the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), the Hamilton Depression Rating Scale (HDRS), the Hamilton Anxiety Rating Scale (HARS), and the Global Assessment of Functioning (GAF) Scale for determining the symptom severity of OCD, depression, and anxiety as well as the quality of pychosocial and occupational functioning, respectively. Neuropsychological assessment consisted of a wide range of tests primarily exploring memory and executive functions. Deep brain stimulation of the ventral caudate nucleus markedly improved symptoms of depression and anxiety until their remission, which was achieved at 6 months after the start of stimulation (HDRS < or = 7 and HARS < or = 10). Remission of OCD (Y-BOCS < 16) was also delayed after 12 or 15 months of DBS. The level of functioning pursuant to the GAF scale progressively increased during the 15-month follow-up period. No neuropsychological deterioration was observed, indicating that DBS of the ventral caudate nucleus could be a promising strategy in the treatment of refractory cases of both OCD and major depression. The introduction of deep brain stimulation (DBS) as a treatment for medication-refractory essential tremor in the late 1980s revealed, for the first time, that "chronically" implanted brain hardware had the potential to modulate neurologic function with surprisingly low morbidity. Over time, the therapeutic promise of DBS has become evident in Parkinson's disease and dystonia. In some experienced centers, complex tremor disorders, such as posttraumatic Holmes tremor and the tremor of multiple sclerosis, are being increasingly targeted. More recently, other indications, including obsessive-compulsive disorder, Tourette's syndrome, major depression, and chronic pain, have been proposed. As the field has expanded, our knowledge about potential cognitive side effects of DBS has also expanded. This article reviews the current knowledge regarding the impact of stimulation of the subthalamic nucleus, globus pallidus internus, and ventralis intermedius nucleus of the thalamus on symptoms in essential tremor, Parkinson's disease, and dystonia. Also discussed are the emerging targets, what is known about the cognitive sequelae of DBS, and what has been learned about the complications and therapeutic failures. The burden of depression as a severe illness with high suicidality and prevalence is immense. Despite substantial advancement in psychopharmacology and psychotherapy over the last decades a residual group of very ill patients with a chronic disease and high suicidal risk remains. Modern theories about the pathophysiology of depression are derived from studies examining the mechanism of antidepressants influencing the serotonergic (5-HT) and noradrenergic (NE) systems. Serotonergic fibers originate from the dorsal raphe nuclei (DRN), noradrenergic fibers from the locus coeruleus (LC). Both nuclei represent relatively small brain regions and both are controlled to some extent by the habenular complex. We propose the hypothesis of an overactivation of the habenula in human major depressive episodes (MDE's). Increased activation of the lateral habenular nucleus leads to the down regulation of the serotonergic, noradrenergic, dopaminergic systems and stimulation of the hypothalamic-pituitary-adrenal (HPA) axis. Functional inhibition of the lateral habenula via deep brain stimulation (DBS) has antidepressive properties. The hypothesis is based on the findings of a clinical imaging study examining the habenular after tryptophan depletion and on several animal studies which are discussed. Providing that our hypothesis will be validated by an analogous tyrosine depletion study and additional preclinical studies, the next logical step would be to directly test our hypothesis in patients. Possible criteria for patient selection, ethical issues and locus of DBS are carefully discussed. Learning that certain actions lead to risky rewards is critical for biological, social, and economic survival, but the precise neural mechanisms of such reward-guided learning remain unclear. Here, we show that the human nucleus accumbens plays a key role in learning about risks by representing reward value. We recorded electrophysiological activity directly from the nucleus accumbens of five patients undergoing deep brain stimulation for treatment of refractory major depression. Patients engaged in a simple reward-learning task in which they first learned stimulus-outcome associations (learning task), and then were able to choose from among the learned stimuli (choosing task). During the learning task, nucleus accumbens activity reflected potential and received reward values both during the cue stimulus and during the feedback. During the choosing task, there was no nucleus accumbens activity during the cue stimulus, but feedback-related activity was pronounced and similar to that during the learning task. This pattern of results is inconsistent with a prediction error response. Finally, analyses of cross-correlations between the accumbens and simultaneous recordings of medial frontal cortex suggest a dynamic interaction between these structures. The high spatial and temporal resolution of these recordings provides novel insights into the timing of activity in the human nucleus accumbens, its functions during reward-guided learning and decision-making, and its interactions with medial frontal cortex. For decades, the most severe, protracted and therapy-resistant forms of major depression have compelled clinicians and researchers to look for last resort treatment. Early psychosurgical procedures were hazardous and often associated with severe and persistent side effects including avolition, apathy and change of personality. With the introduction of psychopharmacological treatments in the 1950s, the frequency of ablative procedures declined rapidly. The past decade, however, has witnessed the resurgence of surgical strategies as a result of refined techniques and advances such as high frequency stimulation of deep brain nuclei. Recent data suggest that the overall effect of high frequency stimulation lies in the functional inhibition of neural activity in the region stimulated. Contrary to other psychosurgical procedures, high frequency stimulation reversibly modulates targeted brain areas and allows a postsurgical adaption of the stimulation parameters according to clinical outcome. With increased understanding of the brain regions and functional circuits involved in the pathogenesis of psychiatric disorders, major depression has emerged as a target for new psychosurgical approaches to selectively and precisely modulate neural areas involved in the disease process. Recent studies of minimally intervening procedures report good clinical outcome in the treatment of therapy-resistant forms of major depression. High frequency stimulation was successfully applied in several small samples of patients with treatment-resistant depression when the stimulation focused on different areas, e.g., nucleus accumbens, the lateral habenula or cortical areas. Nevertheless, the reticence toward psychosurgery, even for those patients suffering from the most debilitating forms of depression, still prevails, even though recent studies have shown significant improvement in terms of quality of life with the limitation that the number of treated cases has been small. In any event, valid and unambiguous criteria for patient eligibility have yet to be refined and standardized. In this review, we suggest possible standard criteria for the application of deep brain stimulation on patients suffering from otherwise treatment-resistant depression. The ventral striatum, including the head of the caudate nucleus and the nucleus accumbens, is a putative target for deep brain stimulation (DBS) in the treatment of obsessive-compulsive disorder (OCD) and major depression (MD). However, the respective roles of these structures in the pathophysiology of OCD and MD remain to be clarified. To address this issue, DBS of the ventral striatum was tested in 2 patients with severely distressing and intractable forms of OCD and MD. Comparisons of clinical outcomes and anatomical data on electrode positioning showed that caudate nucleus stimulation preferentially alleviated OCD manifestations, whereas nucleus accumbens stimulation improved depressive symptoms. These findings suggest that the caudate nucleus and nucleus accumbens participate differently in the pathogenesis of both of these psychiatric conditions. Over the past 20 years, there has been a concerted effort to expand our understanding of the neural circuitry involved in the pathogenesis of psychiatric disorders. Distinct neuronal circuits and networks have been implicated in obsessive compulsive disorder (OCD) and major depressive disorder (MDD) involving feedback loops between the cortex, striatum, and thalamus. When neurosurgery is used as a therapeutic tool in severe OCD and MDD, the goal is to modulate specific targets or nodes within these networks in an effort to produce symptom relief.Currently, four lesioning neurosurgical procedures are utilized for treatment refractory OCD and MDD: cingulotomy, capsulotomy, subcaudate tractotomy, and limbic leucotomy. Deep brain stimulation (DBS) is a novel neurosurgical approach that has some distinct advantages over lesioning procedures. With DBS, the desired clinical effect can be achieved by reversible, high frequency stimulation in a nucleus or at a node in the circuit without the need to produce an irreversible lesion. Recent trials of deep brain stimulation in both OCD and MDD at several neuroanatomical targets have reported promising early results in highly refractory patients and with a good safety profile. Future definitive trials in MDD and OCD are envisaged. Deep brain stimulation (DBS) to the nucleus accumbens (NAcc-DBS) was associated with antidepressant, anxiolytic, and procognitive effects in a small sample of patients suffering from treatment-resistant depression (TRD), followed over 1 year. Results of long-term follow-up of up to 4 years of NAcc-DBS are described in a group of 11 patients. Clinical effects, quality of life (QoL), cognition, and safety are reported. Eleven patients were stimulated with DBS bilateral to the NAcc. Main outcome measures were clinical effect (Hamilton Depression Rating Scale, Montgomery-Asperg Rating Scale of Depression, and Hamilton Anxiety Scale) QoL (SF-36), cognition and safety at baseline, 12 months (n=11), 24 months (n=10), and last follow-up (maximum 4 years, n=5). Analyses were performed in an intent-to-treat method with last observation carried forward, thus 11 patients contributed to each point in time. In all, 5 of 11 patients (45%) were classified as responders after 12 months and remained sustained responders without worsening of symptoms until last follow-up after 4 years. Both ratings of depression and anxiety were significantly reduced in the sample as a whole from first month of NAcc-DBS on. All patients improved in QoL measures. One non-responder committed suicide. No severe adverse events related to parameter change were reported. First-time, preliminary long-term data on NAcc-DBS have demonstrated a stable antidepressant and anxiolytic effect and an amelioration of QoL in this small sample of patients suffering from TRD. None of the responders of first year relapsed during the observational period (up to 4 years). Direct peripheral nerve stimulation is an effective treatment for a number of disorders including epilepsy, depression, neuropathic pain, cluster headache, and urological dysfunction. The efficacy of this stimulation is ultimately due to modulation of activity in the central nervous system. However, the exact brain regions involved in each disorder and how they are modulated by peripheral nerve stimulation is not fully understood. The use of functional neuroimaging such as SPECT, PET and fMRI in patients undergoing peripheral nerve stimulation can help us to understand these mechanisms. We review the literature for functional neuroimaging performed in patients implanted with peripheral nerve stimulators for the above-mentioned disorders. These studies suggest that brain activity in response to peripheral nerve stimulation is a complex interaction between the stimulation parameters, disease type and severity, chronicity of stimulation, as well as nonspecific effects. From this information we may be able to understand which brain structures are involved in the mechanism of peripheral nerve stimulation as well as define the neural substrates underlying these disorders.

Is alemtuzumab effective for remission induction in patients diagnosed with T-cell prolymphocytic leukemia?

Yes, alemtuzumab (anti-CD52, Campath-1H) is effective for remission induction in patients diagnosed with T-cell prolymphocytic leukemia. Alemtuzumab can be administered in combination with other chemotherapeutic agents or as mono-therapy. Response rate to alemtuzumab is more than 90%. Alemtuzumab therapy is associated with improved survival of T-cell prolymphocytic leukemia patients.

Certain features that make an antigen a good candidate for antibody therapy have been defined. CD52 is a 21- to 28-kd nonmodulating cell surface glycosylphosphatidylinositol-linked glycoprotein that is abundantly expressed (up to 5 x 10(5) molecules per cell) on most normal and maligt lymphocytes and monocytes. Its functions are unknown. CD52 is an excellent target for complement-mediated lysis and antibody-dependent cellular cytotoxicity. A series of rat and genetically reshaped human CD52 antibodies has been assessed for the ability to deplete lymphocytes in vivo to induce immunosuppression and for the treatment of lymphoid maligcies. CD52 antibodies that activate both complement and antibody-dependent cellular cytotoxicity consistently deplete lymphocytes from blood, spleen, and bone marrow but are less effective against lymph node disease or extranodal masses. CD52 antibodies provide effective therapy for chronic leukemias, such as T-cell prolymphocytic leukemia and some subtypes of B-cell chronic lymphocytic leukemia, that may be resistant to conventional chemotherapy. For example, most patients with T-cell prolymphocytic leukemia, including those with large tumor burdens and high peripheral white blood cell counts, will enter complete remission using the antibody CAMPATH-1H without any evidence of tumor lysis. In contrast, in chronic lymphocytic leukemia, CD52 antibodies may be more effective in the setting of minimal residual disease and may allow harvesting of uncontaminated stem cells. Further experiments to enhance the activity of CD52 antibodies in sites refractory to antibody alone are currently being undertaken. T-cell prolymphocytic leukemia (T-PLL) is a chemotherapy-resistant maligcy with a median survival of 7.5 months. Preliminary results indicated a high remission induction rate with the human CD52 antibody, CAMPATH-1H. This study reports results in 39 patients with T-PLL treated with CAMPATH-1H between March 1993 and May 2000. All but 2 patients had received prior therapy with a variety of agents, including 30 with pentostatin; none achieved complete remission (CR). CAMPATH-1H (30 mg) was administered intravenously 3 times weekly until maximal response. The overall response rate was 76% with 60% CR and 16% partial remission (PR). These responses were durable with a median disease-free interval of 7 months (range, 4-45 months). Survival was significantly prolonged in patients achieving CR compared to PR or no response (NR), including one patient who survived 54 months. Nine patients remain alive up to 29 months after completing therapy. Seven patients received high-dose therapy with autologous stem cell support, 3 of whom remain alive in CR 5, 7, and 15 months after autograft. Stem cell harvests in these patients were uncontaminated with T-PLL cells as demonstrated by dual-color flow cytometry and polymerase chain reaction. Four patients had allogeneic stem cell transplants, 3 from siblings and 1 from a matched unrelated donor. Two had nonmyeloablative conditioning. Three are alive in CR up to 24 months after allograft. The conclusion is that CAMPATH-1H is an effective therapy in T-PLL, producing remissions in more than two thirds of patients. The use of stem cell transplantation to consolidate responses merits further study. Immunotherapy utilizing CAMPATH-1H for patients with chemotherapy-refractory chronic lymphocytic leukemia has yielded encouraging results with many reports of complete remission. Here we report the outcome of two patients with CD4-positive T cell prolymphocytic leukemia treated with CAMPATH-1H. Both patients responded rapidly to treatment and subsequently developed CD4 lymphopenia. One patient remained in complete remission after 14 weeks of treatment. Serial peripheral blood flow cytometry revealed that the CD52 antigen was present throughout treatment. The other patient who was initially CD52-positive, became CD52-negative after 6 weeks of treatment, and developed progressive symptoms of T cell prolymphocytic leukemia. Immunotherapy was stopped, chemotherapy proved futile, and the patient died. This change in phenotype from CD52-positive to -negative during CAMPATH-1H therapy points out a need to develop strategies for maintaining antigenic expression during monoclonal antibody therapy. Alemtuzumab is a humanized monoclonal antibody against CD52, a small glycosylphosphatidylinositol-anchored glycoprotein that is highly expressed on normal T- and B-lymphocytes, and on a large proportion of maligt lymphoid cells, but not on hematopoietic progenitor cells. Over the past several years, a number of clinical trials have demonstrated the clinical activity of alemtuzumab in treating patients with chronic lymphocytic leukemia, T-cell maligcies such as T-prolymphocytic leukemia and cutaneous T-cell lymphoma, as well as in the prevention and therapy of graft-versus-host disease in the setting of allogeneic stem cell transplantation. Its application in a number of autoimmune disorders is currently under investigation. The most significant side effect of alemtuzumab is predisposition to infections related to the associated profound lymphopenia. Despite this, and with appropriate and more effective antibiotic prophylaxis, it is likely that we will witness an expansion of the role of alemtuzumab in the future. Prolymphocytic leukemia is a rare chronic lymphoproliferative disorder that includes two subtypes, B cell and T cell, each with its own distinct clinical, laboratory and pathological features. T-cell prolymphocytic leukemia has an aggressive course with short median survival and poor response to chemotherapy. With the use of the purine analogue pentostatin more than half of patients will have a major response and a minority will have a complete remission, usually lasting months. With the introduction of alemtuzumab, most patients who progressed despite treatment with pentostatin had a major response with a complete remission rate higher than that obtained with pentostatin when used as a first line. Unfortunately, progression still follows shortly. We recommend alemtuzumab as initial therapy and offer stem cell transplant (SCT) to selected young, healthy patients who respond. Although B-cell prolymphocytic leukemia is also a progressive disease, some patients can achieve a prolonged progression-free-survival with fludarabine. Patients presenting with massive splenomegaly may be effectively palliated with splenic irradiation or splenectomy. Rituximab is a promising agent and further investigations are warranted to better define its role in treatment of this disorder. T-cell maligcies are rare, making up 10% to 15% of all lymphoid neoplasms in adults. They include many different types of disorders such as T-cell prolymphocytic leukemia, T-cell large granular lymphocytic leukemia, adult T-cell leukemia/lymphoma, cutaneous T-cell lymphoma, and peripheral T-cell lymphoma, which are themselves divided into multiple subcategories. Most T-cell maligcies arise as a result of chromosomal abnormalities, including T-cell receptor rearrangement anomalies. Viral infections are implicated in the development of adult T-cell leukemia/lymphoma and some cases of peripheral T-cell lymphoma have been linked to Epstein-Barr virus or human immunodeficiency virus infection. With the possible exception of T-cell large granular lymphocytic leukemia, which often has an indolent course, T-cell maligcies have not responded well to conventional chemotherapeutic treatment. The introduction of monoclonal antibodies for the treatment of cancer has changed the outlook for patients with T-cell maligcies. Recent studies with single-agent alemtuzumab, an anti-CD52 monoclonal antibody, have shown improved response rates and survival in patients with T-cell prolymphocytic leukemia and cutaneous T-cell lymphoma. Preliminary data also suggest that alemtuzumab may have activity in patients with heavily pretreated peripheral T-cell lymphoma who are refractory to conventional chemotherapy. Preclinical studies with mice bearing human adult T-cell leukemia/lymphoma cells suggest that alemtuzumab may have a potential therapeutic role in this setting. Treatment of T-cell hematologic maligcies with alemtuzumab appears promising. Earlier treatment and combination with chemotherapeutic agents may improve treatment outcome for patients with these maligcies and allow for consolidation with stem cell transplant strategies in selected patients. The recent success of monoclonal antibodies in the treatment of various hematological and nonhematological cancers is the result of several decades of research in immune therapy of cancer. The identification of cancer-specific surface markers has led to the development of numerous monoclonal antibodies directed at these antigens, which have been associated with variable success in treating patients with different maligcies. Alemtuzumab, one such monoclonal antibody, is a humanized antibody directed against CD52. The target antigen is a small glycosylphosphatidylinositol (GPI)-anchored glycoprotein that is highly expressed on normal T- and B-lymphocytes and on a large proportion of maligt lymphoid cells, but not on hematopoietic progenitor cells. A number of clinical trials have demonstrated the clinical activity of alemtuzumab in chronic lymphocytic leukemia (CLL), T-cell maligcies such as T-prolymphocytic leukemia (T-PLL) and cutaneous T-cell lymphoma (CTCL), and have examined its role as an immunosuppressive agent in transplantation and for the treatment of autoimmune disorders. Effective antibiotic prophylaxis can limit the incidence of infections, which are the major side effect associated with the profound lymphopenia occurring as a result of treatment with this agent. Intravenous alemtuzumab is an effective and well-tolerated treatment for T-cell prolymphocytic leukemia (T-PLL). Alemtuzumab given intravenously as first-line treatment in 32 patients resulted in an overall response rate of 91% with 81% complete responses. Studies in B-cell chronic lymphocytic leukemia have shown subcutaneous alemtuzumab to be equally as effective as intravenous alemtuzumab. The UKCLL05 pilot study examined the efficacy and toxicity of this more convenient method of administration in 9 previously untreated patients with T-PLL. Only 3 of 9 patients (33%) responded to treatment. Furthermore, 2 of 9 patients (22%) died while on treatment. Recruitment was terminated because of these poor results. After rescue therapy with intravenous alemtuzumab and/or pentostatin, median progression-free survival and overall survival were similar to the intravenous group. Alemtuzumab delivered intravenously, but not subcutaneously, remains the treatment of choice for previously untreated T-PLL. T-cell Prolymphocytic leukemia (T-PLL) is a rare post-thymic T-cell maligcy that follows an aggressive clinical course. The classical presentation includes an elevated white blood cell (WBC) count with anemia and thrombocytopenia, hepatosplenomegaly, and lymphadenopathy. T-PLL is a disease of the elderly and to our knowledge it has never been described in the pediatric age group. We report a case of T-PLL in a 9 year old male who was initially diagnosed with T-cell acute lymphoblastic lymphoma (ALL), the diagnosis was later refined to T-PLL following additional analysis of bone marrow morphology and immunophenotype. Two unusual findings in our patient included CD117 expression and an isolated chromosomal 12(p13) deletion. The patient failed to respond to standard ALL induction chemotherapy, but achieved complete remission following treatment with a fludarabine and alemtuzumab-based regimen. B- and T-cell subtypes of prolymphocytic leukemia (PLL) are rare, aggressive lymphoid maligcies with characteristic morphologic, immunophenotypic, cytogenetic, and molecular features. Prognosis for these patients remains poor, with short survival times and no curative therapy. The advent of mAbs has improved treatment options. In B-PLL, rituximab-based combination chemoimmunotherapy is effective in fitter patients. TP53 abnormalities are common and, as for chronic lymphocytic leukemia, these patients should generally be managed using an alemtuzumab-based therapy. Currently, the best treatment for T-PLL is IV alemtuzumab, which has resulted in very high response rates of more than 90% when given as frontline treatment and a significant improvement in survival. Consolidation of remissions with autologous or allogeneic stem cell transplantation further prolongs survival times, and the latter may offer potential cure. The role of allogeneic transplantation with nonmyeloablative conditioning needs to be explored further in both T- and B-PLL to broaden the patient eligibility for what may be a curative treatment. BACKGROUND: Scarce systematic trial data have prevented uniform therapeutic guidelines for T-cell prolymphocytic leukemia (T-PLL). A central need in this historically refractory tumor is the controlled evaluation of multiagent chemotherapy and its combination with the currently most active single agent, alemtuzumab. METHODS: This prospective multicenter phase 2 trial assessed response, survival, and toxicity of a novel regimen in previously treated (n = 9) and treatment-naive (n = 16) patients with T-PLL. Induction by fludarabine, mitoxantrone, and cyclophosphamide (FMC), for up to 4 cycles, was followed by alemtuzumab (A) consolidation, up to 12 weeks. RESULTS: Of the 25 patients treated with FMC, 21 subsequently received alemtuzumab. Overall response rate to FMC was 68%, comprising 6 complete remissions (all bone-marrow confirmed) and 11 partial remissions. Alemtuzumab consolidation increased the intent-to-treat overall response rate to 92% (12 complete remissions; 11 partial remissions). Median overall survival after FMC-A was 17.1 months and median progression-free survival was 11.9 months. Progression-free survival tended to be shorter for patients with high-level T-cell leukemia 1 oncoprotein expression. Hematologic toxicities were the most frequent grade 3/4 side effects under FMC-A. Exclusively in the 21 alemtuzumab-consolidated patients, 13 cytomegalovirus reactivations were observed; 9 of these 13 represented a clinically relevant infection. CONCLUSIONS: FMC-A is a safe and efficient protocol in T-PLL, which compares favorably to published data. T-cell prolymphocytic leukaemia (T-PLL) is an extremely uncommon haematological maligcy that has an aggressive course and a grave prognosis. We describe a patient who presented with lymphocytosis, scalp erythema, ascites and splenomegaly and was diagnosed with T-PLL. He was treated with alemtuzumab with a good response and was referred for allogeneic stem cell transplantation.

What is the association between moon cycle and rupture risk of intracranial aneurysms?

It has been reported that moon phases correlate with the incidence of aneurysmal subarachnoid hemorrhage due to ruptured intracranial aneurysms. However, other authors have found no correlation between incidence of aneurysmal SAH, location of the aneurysm, initial clinical presentation, or amount of subarachnoid blood and the lunar cycle.

OBJECTIVE: To analyze the impact of the lunar cycle and season on the incidence of aneurysmal subarachnoid hemorrhage (SAH). PATIENTS AND METHODS: The medical records of 111 patients who were admitted over a 5-year period to our department because of aneurysmal SAH were retrospectively reviewed. The date of aneurysm rupture was matched with the corresponding season and moon phase. RESULTS: An incidence peak for aneurysm rupture (28 patients) was seen during the phase of new moon, which was statistically significant (p < 0.001). In contrast, no seasonal variation in the incidence of SAH was observed. CONCLUSION: The lunar cycle seems to affect the incidence of intracranial aneurysm rupture, with the new moon being associated with an increased risk of aneurysmal SAH.

Is there an association between TERT promoter mutation and survival of glioblastoma patients?

Telomerase reverse transcriptase (TERT) promoter are associated with shorter survival of glioblastoma patients. Prognostic value of TERT mutations for poor survival is largely due to their inverse correlation with IDH1 mutations.

BACKGROUND: Glioblastoma multiforme (GBM) is a heterogeneous, highly aggressive primary brain tumor with strongly variable patient survival. Because reliable prognostic biomarkers are lacking, we investigated the relation between telomerase-associated parameters and the disease course. METHODS: Telomerase-associated parameters were determined in 100 GBM tissues and associated with clinical characteristics and overall survival. Expressions of telomere length, telomerase activity (TA), and human telomerase reverse transcriptase (hTERT) were analyzed by quantitative PCR, telomeric repeat amplification protocol assay, and reverse transcriptase-PCR, respectively. Mutation status of isocitrate dehydrogenase (IDH)1 was determined by direct sequencing, and O(6)-methylguanine DNA methyltransferase (MGMT) promoter methylation by methylation-specific PCR. RESULTS: Of 100 GBM tissues, 61 were positive for both hTERT mRNA and TA, with a highly significant correlation between both parameters (linear regression, P < .0001). Telomere length determination revealed a significant difference between the hTERT/TA-positive and -negative subgroups, with markedly longer telomeres in the hTERT/TA-negative cohort (unpaired Student's t-test, P = .0001). Accordingly, significantly shorter telomeres were detected in GBM tissues derived from older patients (>60 y at diagnosis, P < .0001). While no association of telomere parameters with MGMT promoter status was found, all tumors with IDH1 mutation (6/100) were negative for both hTERT expression and TA and harbored significantly longer telomeres. Patients with tumors lacking hTERT expression/TA showed a significant survival benefit (Kaplan-Meier test, both P < .01), which, however, was based exclusively on the younger patient subgroup (≤60 y, both P < .005; >60 y, both ns). CONCLUSIONS: Telomerase activation is not an independent prognostic parameter in GBM but predicts aggressive tumor behavior solely in a younger patient cohort. OBJECTIVE: This study explored the effects of telomerase reverse transcriptase (TERT) promoter mutations on transcriptional activity of the TERT gene under hypoxic and temozolomide (TMZ) treatment conditions, and investigated the status and prognostic value of these mutations in gliomas. METHODS: The effect of TERT promoter mutations on the transcriptional activity of the TERT gene under hypoxic and TMZ treatment conditions was investigated in glioma cells using the luciferase assay. TERT promoter mutations were detected in 101 glioma samples (grades I-IV) and 49 other brain tumors by sequencing. TERT mRNA expression in gliomas was examined by real-time PCR. Hazard ratios from survival analysis of glioma patients were determined relative to the presence of TERT promoter mutations. RESULTS: Mutations in the TERT promoter enhanced gene transcription even under hypoxic and TMZ treatment conditions, inducing upregulation of TERT mRNA expression. Mutations were detected in gliomas, but not in meningiomas, pituitary adenomas, cavernomas, intracranial metastases, normal brain tissues, or peripheral blood of glioma patients. Patients with TERT promoter mutations had lower survival rates, even after adjusting for other known or potential risk factors, and the incidence of mutation was correlated with patient age. CONCLUSION: TERT promoter mutations were specific to gliomas. TERT promoter mutations maintained its ability of inducing high transcriptional activity even under hypoxic and TMZ treatment conditions, and the presence of mutations was associated with poor prognosis in glioma patients. These findings demonstrate that TERT promoter mutations are novel prognostic markers for gliomas that can inform prospective therapeutic strategies.

Is bapineuzumab effective for treatment of patients with Alzheimer's disease?

Clinical trials have demonstrated that bapineuzumab, a humanized monoclonal antibody against the end terminus of amyloid plaques, is not effective for treatment of patients with Alzheimer's disease. The burden of beta amyloid plaques was reduced in response to bapineuzumab therapy. However, bapineuzumab therapy did not improve cognitive functioning and was associated with significant adverse effects in Alzheimer's disease patients.

Ya que la población mundial sigue envejeciendo, la Enfermedad de Alzheimer presenta una crisis inminente para la salud pública, que si se descuida, amenazará con sobrecargar los sistemas de atención de salud en el mundo desarrollado. Para abordar significativamente el síntoma más catastrófico y devastador de la Enfermedad de Alzheimer (EA), la dementia, debemos ser capaces de detectar la enfermedad antes de que aparezcan los síntomas clínicos, y ofrecer a los pacientes tratamientos preventivos que bloqueen o retrasen significativamente la progresión de la enfermedad. Esta revisión resume varios de los métodos más prometedores de detección precoz para la EA y el deterioro cognitivo leve (DCL) que podrían ser utilizados para identificar a los pacientes con alto riesgo de desarrollar la enfermedad y para monitorear la progresión de ésta y la respuesta a tratamientos en investigatión. Además, se destacan algunos de los programas de tratamiento en investigatión que podrían llegar a constituir terapias modificadoras de la enfermedad, que retrasen significativamente el desarrollo de la dementia. Estos potentiates tratamientos están dirigidos a muy diversas vías, y un día podrán ser administrados en combinación para aumentar la eficatia y prévenir el deterioro cognitivo en patientes con EA. Aunque todavía se enfrentan numerosos desafíos, los investigadores de la EA han realizado grandes progresos para la comprensión de los mecanismes de la enfermedad. Como se ha observado en el tratamiento de la enfermedad cardíaca, incluso modestos tratamientos preventives pueden tener un gran impacto en la evolutión clínica y reducir drásticamente la prevalentia de la enfermedad en un subgrupo de la población. Por lo tanto, hay esperanzas en que el desarrollo de tratamientos profilácticos combinado con una mejoría en los métodos de detectión precoz, proveerá un dramático alivio para millones de individuos que están envejeciendo amenazados por el espectro de la Enfermedad de Alzheimer. The field of Alzheimer's disease therapeutic research seems poised to bring to clinic the next generation of treatments, moving beyond symptomatic benefits to modification of the underlying neurobiology of the disease. But a series of recent trials has had disappointingly negative results that raise questions about our drug development strategies. Consideration of ongoing programs demonstrates difficult pitfalls. But a clear path forward is emerging. Successful strategies will utilize newly available tools to reconsider issues of diagnosis, assessment and analysis, facilitating the study of new treatments at early stages in the disease process at which they are most likely to yield major clinical benefits. BACKGROUND: Bapineuzumab, a humanized anti-amyloid-beta (Abeta) monoclonal antibody for the potential treatment of Alzheimer disease (AD), was evaluated in a multiple ascending dose, safety, and efficacy study in mild to moderate AD. METHODS: The study enrolled 234 patients, randomly assigned to IV bapineuzumab or placebo in 4 dose cohorts (0.15, 0.5, 1.0, or 2.0 mg/kg). Patients received 6 infusions, 13 weeks apart, with final assessments at week 78. The prespecified primary efficacy analysis in the modified intent-to-treat population assumed linear decline and compared treatment differences within dose cohorts on the Alzheimer's Disease Assessment Scale-Cognitive and Disability Assessment for Dementia. Exploratory analyses combined dose cohorts and did not assume a specific pattern of decline. RESULTS: No significant differences were found in the primary efficacy analysis. Exploratory analyses showed potential treatment differences (p < 0.05, unadjusted for multiple comparisons) on cognitive and functional endpoints in study "completers" and APOE epsilon4 noncarriers. Reversible vasogenic edema, detected on brain MRI in 12/124 (9.7%) bapineuzumab-treated patients, was more frequent in higher dose groups and APOE epsilon4 carriers. Six vasogenic edema patients were asymptomatic; 6 experienced transient symptoms. CONCLUSIONS: Primary efficacy outcomes in this phase 2 trial were not significant. Potential treatment differences in the exploratory analyses support further investigation of bapineuzumab in phase 3 with special attention to APOE epsilon4 carrier status. CLASSIFICATION OF EVIDENCE: Due to varying doses and a lack of statistical precision, this Class II ascending dose trial provides insufficient evidence to support or refute a benefit of bapineuzumab. Evidence for the involvement of inflammatory processes in the pathogenesis of Alzheimer's disease (AD) has been documented for a long time. However, the inflammation hypothesis in relation to AD pathology has emerged relatively recently. Even in this hypothesis, the inflammatory reaction is still considered to be a downstream effect of the accumulated proteins (amyloid beta (Abeta) and tau). This review aims to highlight the importance of the immune processes involved in AD pathogenesis based on the outcomes of the two major inflammation-relevant treatment strategies against AD developed and tested to date in animal studies and human clinical trials - the use of anti-inflammatory drugs and immunisation against Abeta. BACKGROUND: Carbon-11-labelled Pittsburgh compound B ((11)C-PiB) PET is a marker of cortical fibrillar amyloid-beta load in vivo. We used (11)C-PiB PET to investigate whether bapineuzumab, a humanised anti-amyloid-beta monoclonal antibody, would reduce cortical fibrillar amyloid-beta load in patients with Alzheimer's disease. METHODS: Patients with mild-to-moderate Alzheimer's disease were randomly assigned to receive intravenous bapineuzumab or placebo in a ratio of seven to three in three ascending dose groups (0.5, 1.0, or 2.0 mg/kg). Each dose group was enrolled after safety review of the previous group. Randomisation was by interactive voice response system; masking was achieved with numbered kit allocation. Patients, investigators, study site personnel, sponsor staff, and carers were masked to treatment. Patients received up to six infusions, 13 weeks apart, and had (11)C-PiB PET scans at baseline and at weeks 20, 45, and 78. The primary outcome was the difference between the pooled bapineuzumab group and the pooled placebo group in mean change from screening to week 78 in (11)C-PiB cortical to cerebellar retention ratio averaged across six cortical regions of interest. Analysis was by modified intention to treat. This study is registered with EudraCT, number 2004-004120-12; ISRCTN17517446. FINDINGS: 28 patients were assigned to bapineuzumab (n=20) or placebo (n=8). 19 patients in the bapineuzumab group and seven in the placebo group were included in the modified intention-to-treat analysis. Estimated mean (11)C-PiB retention ratio change from baseline to week 78 was -0.09 (95% CI -0.16 to -0.02; p=0.014) in the bapineuzumab group and 0.15 (95% CI 0.02 to 0.28; p=0.022) in the placebo group. Estimated mean difference in (11)C-PiB retention ratio change from baseline to week 78 between the bapineuzumab group and the placebo group was -0.24 (95% CI -0.39 to -0.09; p=0.003). Differences between the bapineuzumab group and the placebo group in the individual regions of interest were similar to the overall mean difference. Adverse events were typically mild to moderate in severity and transient. Two patients in the 2.0 mg/kg bapineuzumab group had transient cerebral vasogenic oedema. INTERPRETATION: Treatment with bapineuzumab for 78 weeks reduced cortical (11)C-PiB retention compared with both baseline and placebo. (11)C-PiB PET seems to be useful in assessing the effects of potential Alzheimer's disease treatments on cortical fibrillar amyloid-beta load in vivo. FUNDING: Elan Pharmaceuticals and Wyeth Research. Pre-clinical and clinical data suggest that the development of a safe and effective anti-amyloid-beta (Abeta) immunotherapy for Alzheimer's disease (AD) will require therapeutic levels of anti-Abeta antibodies, while avoiding proinflammatory adjuvants and autoreactive T cells which may increase the incidence of adverse events in the elderly population targeted to receive immunotherapy. The first active immunization clinical trial with AN1792 in AD patients was halted when a subset of patients developed meningoencephalitis. The first passive immunotherapy trial with bapineuzumab, a humanized monoclonal antibody against the end terminus of Abeta, also encountered some dose dependent adverse events during the Phase II portion of the study, vasogenic edema in 12 cases, which were significantly over represented in ApoE4 carriers. The proposed remedy is to treat future patients with lower doses, particularly in the ApoE4 carriers. Currently there are at least five ongoing anti-Abeta immunotherapy clinical trials. Three of the clinical trials use humanized monoclonal antibodies, which are expensive and require repeated dosing to maintain therapeutic levels of the antibodies in the patient. However in the event of an adverse response to the passive therapy antibody delivery can simply be halted, which may provide a resolution to the problem. Because at this point we cannot readily identify individuals in the preclinical or prodromal stages of AD pathogenesis, passive immunotherapy is reserved for those that already have clinical symptoms. Unfortunately those individuals have by that point accumulated substantial neuropathology in affected regions of the brain. Moreover, if Abeta pathology drives tau pathology as reported in several transgenic animal models, and once established if tau pathology can become self propagating, then early intervention with anti-Abeta immunotherapy may be critical for favorable clinical outcomes. On the other hand, active immunization has several significant advantages, including lower cost and the typical immunization protocol should be much less intrusive to the patient relative to passive therapy, in the advent of Abeta-antibody immune complex-induced adverse events the patients will have to receive immuno-supperssive therapy for an extended period until the anti Abeta antibody levels drop naturally as the effects of the vaccine decays over time. Obviously, improvements in vaccine design are needed to improve both the safety, as well as the efficacy of anti-Abeta immunotherapy. The focus of this review is on the advantages of DNA vaccination for anti-Abeta immunotherapy, and the major hurdles, such as immunosenescence, selection of appropriate molecular adjuvants, universal T cell epitopes, and possibly a polyepitope design based on utilizing existing memory T cells in the general population that were generated in response to childhood or seasonal vaccines, as well as various infections. Ultimately, we believe that the further refinement of our AD DNA epitope vaccines, possibly combined with a prime boost regime will facilitate translation to human clinical trials in either very early AD, or preferably in preclinical stage individuals identified by validated AD biomarkers. The amyloid hypothesis provides a basis for the development of new therapeutic strategies in Alzheimer's disease. Two large trials have recently been published. The first is a phase 2 study of passive immunotherapy with bapineuzumab, a humanized anti-Abeta monoclonal antibody directed against the N-terminus of Abeta. This trial showed no differences within dose cohorts on the primary efficacy analysis. Exploratory analyses showed potential treatment differences on cognitive and functional endpoints in study completers and apolipoprotein E epsilon4 noncarriers. A safety concern was the occurrence of reversible vasogenic edema. The second study is a phase 3 trial of tarenflurbil, a modulator of the activity of gamma-secretase. Tarenflurbil had no beneficial effect on the primary or secondary outcomes. The tarenflurbil group had a small increase in frequency of dizziness, anemia, and infections. Possible explanations for the negative results of these trials may be related to the study design or the choice of dosage. However, it may also be that these negative findings reflect our still incomplete understanding of, at least part of, the pathogenesis of Alzheimer's disease. IMPORTANCE OF THE FIELD: Alzheimer's disease is the leading cause of dementia in the elderly, and there is no disease-modifying therapy yet available. Immunotherapy directed against the beta-amyloid peptide may be capable of slowing the rate of disease progression. Bapineuzumab, an anti-beta-amyloid monoclonal antibody, will be the first such agent to emerge from Phase III clinical trials. AREAS COVERED IN THIS REVIEW: The primary literature on bapineuzumab from 2009 and 2010 is reviewed in its entirety, along with the literature on AN1792, a first-generation anti-beta-amyloid vaccine, from 2003 to 2009. Other Alzheimer's disease immunotherapeutics currently in development, according to www.clinicaltrials.gov , are also discussed. WHAT THE READER WILL GAIN: In addition to a critical appraisal of the Phase II trial results for bapineuzumab, this review considers the broader field of immunotherapy for Alzheimer's disease as a whole, including the challenges ahead. TAKE HOME MESSAGE: Bapineuzumab appears capable of reducing the cerebral beta-amyloid peptide burden in patients with Alzheimer's disease. However, particularly in APOE 4 carriers, its ability to slow disease progression remains uncertain, and vasogenic edema - a dose-limiting and potentially severe adverse reaction - may limit its clinical applicability. BACKGROUND: Active and passive immunotherapy in both amyloid-beta precursor protein (APP) transgenic mice and Alzheimer's Disease (AD) patients have resulted in remarkable reductions in amyloid plaque accumulation, although the degree of amyloid regression has been highly variable. Nine individuals with a clinical diagnosis of AD dementia were actively immunized with the Aβ peptide 1-42 (AN-1792) and subjected to detailed postmortem biochemical analyses. These patients were compared to 6 non-immunized AD cases and 5 non-demented control (NDC) cases. RESULTS: All patients were assessed for the presence of AD pathology including amyloid plaques, neurofibrillary tangles and vascular amyloidosis. This effort revealed that two immunotherapy recipients had dementia as a consequence of diseases other than AD. Direct neuropathological examination consistently demonstrated small to extensive areas in which amyloid plaques apparently were disrupted. Characterization of Aβ species remts by ELISA suggested that total Aβ levels may have been reduced, although because the amounts of Aβ peptides among treated individuals were extremely variable, those data must be regarded as tentative. Chromatographic analysis and Western blots revealed abundant dimeric Aβ peptides. SELDI-TOF mass spectrometry demonstrated a substantive number of Aβ-related peptides, some of them with elongated C-terminal sequences. Pro-inflammatory TNF-α levels were significantly increased in the gray matter of immunized AD cases compared to the NDC and non-immunized AD groups. CONCLUSIONS: Immunotherapy responses were characterized by extreme variability. Considering the broad range of biological variation that characterizes aging and complicates the recognition of reliable AD biomarkers, such disparities will make the interpretation of outcomes derived from epidemiologic and therapeutic investigations challenging. Although in some cases the apparent removal of amyloid plaques by AN-1792 was impressive, proportionate alterations in the clinical progression of AD were not evident. The fact that plaque elimination did not alter the trajectory of decline into dementia suggests the likelihood that these deposits alone are not the underlying cause of dementia. The field of Alzheimer's disease (AD) research eagerly awaits the results of a large number of Phase III clinical trials that are underway to investigate the effectiveness of anti-amyloid-β (Aβ) immunotherapy for AD. In this case report, we review the pertinent clinical history, examine the neuropathology, and characterize the Aβ profile of an AD patient who received bapineuzumab immunotherapy. The patient received four bapineuzumab infusions over a 39 week period. During the course of this treatment, there was no remarkable change in cognitive impairment as determined by MMSE scores. Forty-eight days after the fourth bapineuzumab infusion was given, MRI revealed that the patient had developed lacunar infarcts and possible vasogenic edema, probably related to immunotherapy, but a subsequent MRI scan 38 days later demonstrated resolution of vasogenic edema. The patient expired due to acute congestive heart failure complicated by progressive AD and cerebrovascular accident 378 days after the first bapineuzumab infusion and 107 days after the end of therapy. Neuropathological and biochemical analysis did not produce evidence of lasting plaque regression or clearance of Aβ due to immunotherapy. The Aβ species profile of this case was compared with non-immunized AD cases and non-demented controls and found to be similar to non-immunized AD cases. SELDI-TOF mass spectrometric analysis revealed the presence of full-length Aβ₁₋₄₂ and truncated Aβ peptides demonstrating species with and without bapineuzumab specific epitopes. These results suggest that, in this particular case, bapineuzumab immunotherapy neither resulted in detectable clearance of amyloid plaques nor prevented further cognitive impairment. Several second-generation active β-amyloid (Aβ) vaccines and passive Aβ immunotherapies are under clinical investigation with the aim of boosting Aβ clearance from the brain of the Alzheimer's disease (AD) patients. However, the preliminary cognitive efficacy of bapineuzumab, a humanized anti-Aβ monoclonal antibody, appears uncertain. Moreover, the occurrence of vasogenic edema and, more rarely, brain microhemorrhages, especially in apolipoprotein E ϵ4 carriers, have led to abandoning of the highest dose of the drug. Solanezumab, another humanized anti-Aβ monoclonal antibody, was shown to neutralize soluble Aβ oligomers, which is believed to be the more neurotoxic Aβ species. Phase II studies showed a good safety profile of solanezumab while studies on cerebrospinal and plasma biomarkers documented good signals of pharmacodynamic activity. However, the preliminary equivocal cognitive results obtained with bapineuzumab as well as the detrimental cognitive effects observed with semagacestat, a potent γ-secretase inhibitor, raise the possibility that targeting Aβ may not be clinically efficacious in AD. The results of four ongoing large Phase III trials on bapineuzumab and two Phase III trials on solanezumab will tell us if passive anti-Aβ immunization is able to alter the course of this devastating disease, and if Aβ is still a viable target for anti-AD drugs. Conflict of interest statement: Conflicts of Interest RS has served as a study investigator and a consultant for Janssen Alzheimer Immunotherapy Research & Development, LLC, and for Pfizer Inc., and has received honoraria for participation in symposiums. She has also served as a consultant and/or site investigator for Bristol-Myers-Squibb, Roche, Elan, Biogen-IDEC, Avid, and Bayer. SS has served as a consultant and study investigator for Janssen Alzheimer Immunotherapy Research & Development, LLC., Pfizer Inc., and Elan Corporation, plc. phase 2 and 3 studies of bapineuzumab. DB reports no conflicts of interest. DT provides review of MRI images for Janssen Alzheimer Immunotherapy Research & Development, LLC. JB serves as a neuroradiological consultant to SYNARC Inc., an imaging contract research organization contracted by both sponsor companies (Janssen Alzheimer Immunotherapy Research & Development, LLC. and Pfizer Inc.); he also serves as a consultant to Janssen Alzheimer Immunotherapy Research & Development, LLC. for non-clinical research activities. NF has provided consulting and/or image analysis services to Elan Corporation, plc., Janssen Alzheimer Immunotherapy Research & Development, LLC., Pfizer Inc., and Wyeth Pharmaceuticals as well as to AstraZeneca, Bristol-Myers Squibb, Eli Lilly and Company, GE Healthcare, Lundbeck A/S, and IXICO. MR serves as consultant to Janssen Alzheimer Immunotherapy Research & Development, LLC. MS participates in a consulting/advisory capacity for Eli Lilly and Company, Amerisciences, Takeda Pharmaceuticals Inc., Eisai Co., Ltd., Pfizer Inc., and GlaxoSmithKline plc. and receives royalties from Wiley and AmeriSciences, LP. He receives contracting fees/grants from Celgene Corporation, Ceregene, Inc., Bayer AG, Baxter International Inc., Bristol-Myers Squibb, Eli Lilly and Company, Pfizer Inc., Janssen Alzheimer Immunotherapy Research & Development, LLC., Avid Radiopharmaceuticals, Inc., Genentech, Inc. and Eisai Co., Ltd. LH serves on the study steering committee and has acted as a consultant for Janssen Alzheimer Immunotherapy Research & Development, LLC., but receives less than $10,000 annually for such consulting activities. AP has received grant/research support from Baxter International Inc., Bristol-Myers Squibb, Eisai Co., Ltd., Elan Corporation, plc., Genentech, Inc./ Hoffmann-La Roche Inc., Janssen Alzheimer Immunotherapy Research & Development, LLC., Medivation, Inc., Pfizer Inc., and Toyama Chemical Co., Ltd. He has also served as a consultant/participated on advisory boards for Elan Corporation, plc., Janssen Alzheimer Immunotherapy Research & Development, LLC., Medivation, Inc., Pfizer Inc., Transition Therapeutics Inc., and Toyama Chemical Co., Ltd.. He is also a member of the speakers’ bureau for Forest Laboratories, Inc. IL is a stockholder in Elan Corporation, plc. RB is an employee of and receives stock and stock options from Pfizer Inc. MA, KM, YL, EL, KG, RHB, and GK are employees of Janssen Alzheimer Immunotherapy Research & Development, LLC. MG is a consultant to Janssen Alzheimer Immunotherapy Research & Development, LLC. and is a stockholder in Elan Corporation, plc. The exact mechanisms leading to Alzheimer's disease (AD) are largely unknown, limiting the identification of effective disease-modifying therapies. The two principal neuropathological hallmarks of AD are extracellular β-amyloid (Aβ), peptide deposition (senile plaques) and intracellular neurofibrillary tangles containing hyperphosphorylated tau protein. During the last decade, most of the efforts of the pharmaceutical industry were directed against the production and accumulation of Aβ. The most innovative of the pharmacological approaches was the stimulation of Aβ clearance from the brain of AD patients via the administration of Aβ antigens (active vaccination) or anti-Aβ antibodies (passive vaccination). Several active and passive anti-Aβ vaccines are under clinical investigation. Unfortunately, the first active vaccine (AN1792, consisting of preaggregate Aβ and an immune adjuvant, QS-21) was abandoned because it caused meningoencephalitis in approximately 6% of treated patients. Anti-Aβ monoclonal antibodies (bapineuzumab and solanezumab) are now being developed. The clinical results of the initial studies with bapineuzumab were equivocal in terms of cognitive benefit. The occurrence of vasogenic edema after bapineuzumab, and more rarely brain microhemorrhages (especially in Apo E ε4 carriers), has raised concerns on the safety of these antibodies directed against the N-terminus of the Aβ peptide. Solanezumab, a humanized anti-Aβ monoclonal antibody directed against the midregion of the Aβ peptide, was shown to neutralize soluble Aβ species. Phase II studies showed a good safety profile of solanezumab, while studies on cerebrospinal and plasma biomarkers documented good signals of pharmacodynamic activity. Although some studies suggested that active immunization may be effective against tau in animal models of AD, very few studies regarding passive immunization against tau protein are currently available. The results of the large, ongoing Phase III trials with bapineuzumab and solanezumab will tell us if monoclonal anti-Aβ antibodies may slow down the rate of deterioration of AD. Based on the new diagnostic criteria of AD and on recent major failures of anti-Aβ drugs in mild-to-moderate AD patients, one could argue that clinical trials on potential disease-modifying drugs, including immunological approaches, should be performed in the early stages of AD. Several anti-amyloid β (Aβ) antibodies are under evaluation for the treatment of Alzheimer's disease (AD). Clinical studies using the N-terminal-directed anti-Aβ antibody bapineuzumab have demonstrated reduced brain PET-Pittsburg-B signals, suggesting the reduction of Aβ plaques, and reduced levels of total and phosphorylated tau protein in the CSF of treated AD patients. Preclinical studies using 3D6 (the murine form of bapineuzumab) have demonstrated resolution of Aβ plaque and vascular burdens, neuritic dystrophy, and preservation of synaptic density in the transgenic APP mouse models. In contrast, few studies have evaluated the direct interaction of this antibody with synaptotoxic soluble Aβ species. In the current report, we demonstrated that 3D6 binds to soluble, synaptotoxic assemblies of Aβ(1-42) and prevents multiple downstream functional consequences in rat hippocampal neurons including changes in glutamate AMPA receptor trafficking, AD-type tau phosphorylation, and loss of dendritic spines. In vivo, we further demonstrated that 3D6 prevents synaptic loss and acutely reverses the behavioral deficit in the contextual fear conditioning task in transgenic mouse models of AD, two endpoints thought to be linked to synaptotoxic soluble Aβ moieties. Importantly C-terminal anti-Aβ antibodies were ineffective on these endpoints. These results, taken with prior studies, suggest that N-terminal anti-Aβ antibodies effectively interact with both soluble and insoluble forms of Aβ and therefore appear particularly well suited for testing the Aβ hypothesis of AD. At this time there are no effective methods to alter the disease course in Alzheimer's disease. All FDA approved interventions are for symptomatic relief only. However, it is an exciting time as many agents in development have theorhetical potential to impact the disease course. This review discusses some of the agents that have been in clinical trials, particularly those that affect amyloid processing. Some agents have failed while others still provide hope. Since amyloid is the peptide most closely linked to disease pathogenesis, it is possible that some of the anti-amyloid agents will impact the disease progression in a meaningful way. Introduction. Amyloid-beta-related angiitis (ABRA) is a form of CNS vasculitis in which perivascular beta-amyloid in the intracerebral vessels is thought to act as a trigger for inflammation mediated by CD68+ macrophages and CD3+ T lymphocytes. Patients with severe ABRA may develop coma responsive to immunosuppressive treatment. Case Presentation. A 57-year-old man presented to the neurological intensive care unit febrile, obtunded, and with a left hemiparesis. He had suffered from intermittent left arm weakness and numbness for several months prior. Serum and cerebrospinal fluid studies showed a lymphocytic leukocytosis in the cerebrospinal fluid (CSF), but no other evidence of infection, and the patient underwent a brain biopsy. Histopathological examination demonstrated amyloid angiopathy, with an extensive perivascular lymphocytic infiltrate, indicative of ABRA. The patient was started on cyclophosphamide and steroids. Following a week of treatment he awakened and over several weeks made a significant neurological recovery. Conclusions. ABRA can have a variety of clinical presentations, including impairments in consciousness and coma. Accurate pathological diagnosis, followed by aggressive immunosuppression, can lead to impressive neurological improvements. This diagnosis should be considered in patients with paroxysmal recurrent neurological symptoms and an accelerated progression. The lack of progress in the development of disease-modifying therapy in Alzheimer's disease (AD) was highlighted recently by the cessation of a phase 3 clinical trial studying the effects of bapineuzumab on mild to moderate disease. No treatment benefit was apparent, whereas several serious side effects occurred more commonly in the treatment group compared to placebo. This is the latest failure in a now long list of trials targeting lesional proteins believed to be fundamental drivers of the disease process. As the focus of the trial is directly tied to ostensible disease pathogenesis, objectivity compels us yet again to re-examine the amyloid cascade hypothesis as even a marginally significant pathogenic mediator of disease and to perhaps revert back to traditional science where repeated negative data leads one to consider other ideas. In the case of AD, amyloid-β metabolism and tau phosphorylation have been exhaustively studied, both to no avail. Oxidative stress has similarly been examined in detail by multiple mechanisms and targeted for treatment with a similar result. An appeal to the scientific community may be made to consider lesions in a different light. Have we been seduced by so-called hallmark lesions into believing that they are responsible for disease when in fact the reverse is true, and will we genuinely consider a systems biology approach to AD or instead continue on the path of the lesion, which has so far followed a flat line of progress? Alzheimer's disease (AD) is a neurodegenerative disorder that impairs mainly the memory and cognitive function in elderly. Extracellular beta amyloid deposition and intracellular tau hyperphosphorylation are the two pathological events that are thought to cause neuronal dysfunction in AD. Since the detailed mechanisms that underlie the pathogenesis of AD are still not clear, the current treatments are those drugs that can alleviate the symptoms of AD patients. Recent studies have indicated that these symptom-reliving drugs also have the ability of regulating amyloid precursor protein processing and tau phosphorylation. Thus the pharmacological mechanism of these drugs may be too simply-evaluated. This review summarizes the current status of AD therapy and some potential preclinical considerations that target beta amyloid and tau protein are also discussed. Early detection of neurodegenerative diseases: circulating brain-enriched microRNA. Bapineuzumab is a humanized antibody developed by Pfizer and Johnson & Johnson targeting the amyloid (Aβ) plaques that underlie Alzheimer's disease neuropathology. Here we report the crystal structure of a Fab-Aβ peptide complex that reveals Bapineuzumab surprisingly captures Aβ in a monomeric helical conformation at the N-terminus. Microscale thermophoresis suggests that the Fab binds soluble Aβ(1-40) with a K(D) of 89 (±9) nM. The structure explains the antibody's exquisite selectivity for particular Aβ species and why it cannot recognize N-terminally modified or truncated Aβ peptides. Bapineuzumab, an investigational agent for Alzheimer's disease. Alzheimer's disease (AD) is the most common dementia in the industrialized world, with prevalence rates well over 30% in the over 80-years-old population. The dementia causes enormous costs to the social healthcare systems, as well as personal tragedies for the patients, families and caregivers. AD is strongly associated with Amyloid-beta (Aβ) protein aggregation, which results in extracellular plaques in the brain, and according to the amyloid cascade hypothesis appeared to be a promising target for the development of AD therapeutics. Within the past decade convincing data has arisen positioning the soluble prefibrillar Aβ-aggregates as the prime toxic agents in AD. However, different Aβ aggregate species are described but their remarkable metastability hampers the identification of a target species for immunization. Passive immunotherapy with monoclonal antibodies (mAbs) against Aβ is in late clinical development but recently the two most advanced mAbs, Bapineuzumab and Solanezumab, targeting an N-terminal or central epitope, respectively, failed to meet their target of improving or stabilizing cognition and function. Preliminary data from off-label treatment of a small cohort for 3 years with intravenous polyclonal immunoglobulins (IVIG) that appear to target different conformational epitopes indicate a cognitive stabilization. Thus, it might be the more promising strategy reducing the whole spectrum of Aβ-aggregates than to focus on a single aggregate species for immunization. An international task force of investigators from academia, industry, nonprofit foundations, and regulatory agencies met in Monte Carlo, Monaco, on October 31, 2012, to review lessons learned from the recent bapineuzumab and solanezumab trials, and to incorporate insights gained from these trials into future clinical studies. Although there is broad consensus that Alzheimer's disease (AD) should be treated during its earliest stages, the concept of secondary prevention has evolved to be described more accurately as treatment of preclinical, presymptomatic, or early AD. There continues to be a strong emphasis on biomarkers and a need for new biomarkers; however, there has also been a realization, based on completed trials, that the most reliable indicator of clinical efficacy across the entire spectrum of disease from asymptomatic to AD dementia is likely a measure of cognition. The task force made many recommendations that should improve the likelihood of success in future trials, including larger phase 2 or combined phase 2/phase 3 studies, clear evidence of target engagement in the central nervous system, evidence of downstream effects on biomarkers before initiating phase 3 studies, consideration of adaptive and targeted trial designs, and use of sensitive measures of cognition as the most robust indicator of treatment benefit. Alzheimer's disease (AD) is the most common neurodegenerative disorder. Currently available therapies are symptomatic but do not alter underlying disease progression. Immunotherapeutic approaches such as anti Aβ peptide active vaccination trials have had limited success to date. Intravenous immunoblobulin (IVIg) is widely used in immune-mediated neurological disorders such myasthenia gravis and Guillain-Barre syndrome. These preparations have been obtained from the pooled plasma of healthy human donors and contain natural anti-amyloid antibodies and are well tolerated. A small pilot study of passive immunotherapy using IVIg has suggested cognitive improvement. A multicenter phase III trial is ongoing and will determine whether or not this treatment can ameliorate cognitive deficits in mild-to-moderate AD. Here, we briefly review the pathogenic role of amyloid and tau in AD, as well as immunotherapeutic efforts to date. We also summarize what is known about naturally occurring anti-Aβ and tau antibodies in IVIg with a view toward explaining potential mechanisms underlying their therapeutic effects. Recent studies have suggested a protective role of physiological β-amyloid autoantibodies (Aβ-autoantibodies) in Alzheimer's disease (AD). However, the determination of both free and dissociated Aβ-autoantibodies in serum hitherto has yielded inconsistent results regarding their function and possible biomarker value. Here we report the application of a new sandwich enzyme-linked immunosorbent assay (ELISA) for the determination of antigen-bound Aβ-autoantibodies (intact Aβ-IgG immune complexes) in serum and cerebrospinal fluid (CSF) of a total number of 112 AD patients and age- and gender-matched control subjects. Both serum and CSF levels of Aβ-IgG immune complexes were found to be significantly higher in AD patients compared to control subjects. Moreover, the levels of Aβ-IgG complexes were negatively correlated with the cognitive status across the groups, increasing with declining cognitive test performance of the subjects. Our results suggest a contribution of IgG-type autoantibodies to Aβ clearance in vivo and an increased immune response in AD, which may be associated with deficient Aβ-IgG removal. These findings may contribute to elucidating the role of Aβ-autoantibodies in AD pathophysiology and their potential application in AD diagnosis. Alzheimer's disease (AD) is characterized by brain accumulation of the neurotoxic amyloid-β peptide (Aβ) and by loss of cholinergic neurons and nicotinic acetylcholine receptors (nAChRs). Recent evidence indicates that memory loss and cognitive decline in AD correlate better with the amount of soluble Aβ than with the extent of amyloid plaque deposits in affected brains. Inhibition of nAChRs by soluble Aβ40 is suggested to contribute to early cholinergic dysfunction in AD. Using phage display screening, we have previously identified a heptapeptide, termed IQ, homologous to most nAChR subtypes, binding with omolar affinity to soluble Aβ40 and blocking Aβ-induced inhibition of carbamylcholine-induced currents in PC12 cells expressing α7 nAChRs. Using alanine scanning mutagenesis and whole-cell current recording, we have now defined the amino acids in IQ essential for reversal of Aβ40 inhibition of carbamylcholine-induced responses in PC12 cells, mediated by α7 subtypes and other endogenously expressed nAChRs. We further investigated the effects of soluble Aβ, IQ and analogues of IQ on α3β4 nAChRs recombitly expressed in HEK293 cells. Results show that omolar concentrations of soluble Aβ40 potently inhibit the function of α3β4 nAChRs, and that subsequent addition of IQ or its analogues does not reverse this effect. However, co-application of IQ makes the inhibition of α3β4 nAChRs by Aβ40 reversible. These findings indicate that Aβ40 inhibits different subtypes of nAChRs by interacting with specific receptor domains homologous to the IQ peptide, suggesting that IQ may be a lead for novel drugs to block the inhibition of cholinergic function in AD. In recent years, efforts have been directed to develop "disease-modifying" medications to treat Alzheimer's disease (AD), able to halt or slow the pathological process. Because the earlier the treatment starts, the greater is the possibility of efficacy, it is important to set up biomarkers for early diagnosis of functional brain abnormalities, before the clinical manifestation of the overt disease. Up to now, strategies to develop disease-modifying drugs have mainly targeted β amyloid (Aβ, accumulation, aggregation, clearance) and/or tau protein (phosphorylation and aggregation). Active and passive immunotherapy is the main strategy aimed at increasing Aβ clearance. Unfortunately several candidate diseasemodifying drugs have failed in phase III clinical trials conducted in mild to moderate AD. More recently, in phase III studies, bapineuzumab has been discontinued because it did not prove clinically effective (despite its significant effect on biomarkers), while solaneuzumab has been found effective in slowing AD progression. Several methological problems have been recently pointed out to explain the lack of clinical efficacy of novel disease-modifying drug-treatments; moreover, new insights in pathophysiology of AD give the premise to develop novel drug targeting. Clinical trials recently completed and/or still ongoing are discussed in the present review. Alzheimer's disease, which is characterized by gradual cognitive decline associated with deterioration of daily living activities and behavioral disturbances throughout the course of the disease, is estimated to affect 27 million people around the world. It is expected that the illness will affect about 63 million people by 2030, and 114 million by 2050, worldwide. Current Alzheimer's disease medications may ease symptoms for a time but are not capable of slowing down disease progression. Indeed, all currently available therapies, such as cholinesterase inhibitors (donepezil, galantamine, rivastigmine), are primarily considered symptomatic therapies, although recent data also suggest possible disease-modifying effects. Gantenerumab is an investigational fully human anti-amyloid beta monoclonal antibody with a high capacity to bind and remove beta-amyloid plaques in the brain. This compound, currently undergoing Phase II and III clinical trials represents a promising agent with a disease-modifying potential in Alzheimer's disease. Here, we present an overview of gantenerumab ranging from preclinical studies to human clinical trials. Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease, and corresponds to the most common cause of dementia worldwide. Although not fully understood, the pathophysiology of AD is largely represented by the neurotoxic events triggered by the beta-amyloid cascade and by cytoskeletal abnormalities subsequent to the hyperphosphorylation of microtubule-associated Tau protein in neurons. These processes lead respectively to the formation of neuritic plaques and neurofibrillary tangles, which are the pathological hallmarks of the disease. Clinical benefits of the available pharmacological treatment for AD with antidementia drugs (namely cholinesterase inhibitors and memantine) are unquestionable, although limited to a temporary, symptomatic support to cognitive and related functions. Over the past decade, substantial funding and research have been dedicated to the search and development of new pharmaceutical compounds with disease-modifying properties. The rationale of such approach is that by tackling key pathological processes in AD it may be possible to attenuate or even change its natural history. In the present review, we summarize the available evidence on the new therapeutic approaches that target amyloid and Tau pathology in AD, focusing on pharmaceutical compounds undergoing phase 2 and phase 3 randomized controlled trials.

Which deiodinase polymorphisms are implicated in arterial hypertension?

Two deiodinase polymorphisms are implicated in arterial hypertension: Ala92 type 2 deiodinase allele and rs7140952 polymorphism of DIO2

Accumulating evidence suggests that genes of the hypothalamic-pituitary-thyroid pathway influence susceptibility to hypertension. Type 2 iodothyronine deiodinase is responsible for the conversion of thyroxine to tri-iodothyronine for use in peripheral tissues. The present study evaluated whether a type 2 iodothyronine deiodinase nonsynonymous polymorphism, threonine 92 to alanine (Thr92Ala), is a determit of hypertension susceptibility. A total of 372 euthyroid subjects were genotyped for Thr92Ala polymorphism using the Sequenom MassARRAY platform. Associations with hypertension and hypertension-related intermediate phenotypes were performed with generalized estimating equations. Type 2 iodothyronine deiodinase Thr92Ala allele frequencies differed significantly between hypertensive and normotensive subjects, with an excess of Ala92 carriers in hypertensive compared with normotensive subjects (64.8% versus 47.1%; P=0.011). Adjusted for age, gender and race, the estimated odds ratio for hypertension in Ala92 allele carriers compared with Thr92 homozygotes was 2.11 (95% CI: 1.15 to 3.89). Among euthyroid adults, the common Ala92 allele of the type 2 iodothyronine deiodinase increases risk for the development of hypertension. These data support an important role for genetic variation in the hypothalamic-pituitary-thyroid pathway in influencing susceptibility to hypertension. BACKGROUND: Overt hypothyroidism has been associated with arterial hypertension and increased arterial stiffness. Results in euthyroid individuals have been conflicting. We investigated associations of thyroid function with systolic (SAP) and diastolic (DAP) arterial pressure in euthyroid subjects. METHODS: 311 euthyroid individuals (185 women, mean age 43.9 +/- 9) without a history of diabetes attending a preventive medicine program were examined. Subjects receiving thyroxine (10.6%) were excluded; 19.3% had hypertension, 43% had a family history for hypertension. TSH, fT4, thyroid autoantibodies, insulin, glucose were measured. The "fT4.TSH product", which has been suggested as a T4 resistance-index, was calculated. RESULTS: TSH range was 0.1-8, median 1.4 mU/L, fT4 range was 11.5-25.2 pmol/L, median 17.4. TSH and the "fT4.TSH product" were positively associated with DAP (p < 0.03, for both associations). In the subgroup of individuals with TSH levels 0.36-2.5 mU/L, both TSH and the "fT4.TSH product" were positively correlated with SAP (r = +0.133 p = 0.044, r = +0.152 p = 0.026) and DAP (r = +0.243 p < 0.001, r = +0.252 p < 0.001 respectively); in multivariate analysis the "fT4.TSH product" was a significant predictor of DAP independently of HOMA-IR and BMI (p < 0.001). Similar associations were found when only the non-hypertensive subjects were analysed (p = 0.004). Hypertensive patients had higher TSH levels (p = 0.02) and belonged more frequently to the subgroup with TSH > 2 mU/L (35.3% vs 21.3%, p = 0.045). CONCLUSION: In euthyroid individuals the association of thyroid function with diastolic arterial pressure remains significant even when a stricter "normal range" for TSH levels is considered. The "freeT4.TSH" product appears to be an even stronger predictor of DAP, independently of HOMA insulin resistance index and obesity. INTRODUCTION: Thyroid function and genetic variation in the hypothalamus-pituitary-thyroid axis have been implicated in blood pressure regulation and susceptibility to hypertension. However studies conducted thus far were small with controversial results. OBJECTIVE: To examine whether serum thyroid parameters and polymorphisms in the type 2 deiodinase and the TSH receptor are associated with blood pressure and the presence of hypertension in two large cohorts of elderly subjects. DESIGN AND PARTICIPANTS: We studied a random sample of 1444 subjects of the Rotterdam study, and 997 subjects of the Rotterdam Scan study, two population-based cohort studies among elderly individuals aged 55-90 years. Outcome measurements Data on blood pressure and hypertension were obtained, and serum thyroid parameters, D2-Thr92Ala, D2-ORFa-Gly3Asp and TSHR-Asp727Glu polymorphisms were determined. RESULTS: In contrast to previous findings, no consistent and/or significant associations were found between serum TSH and FT4 and blood pressure in both cohorts. In addition, the D2-Thr92Ala, D2-ORFa-Gly3Asp and TSHR-Asp727Glu polymorphisms were not associated with blood pressure or the risk of hypertension. CONCLUSIONS: In two large populations of elderly subjects, neither serum thyroid parameters nor polymorphisms in the type 2 deiodinase and the TSH receptor, were associated with blood pressure or the presence of hypertension. Our data suggest that thyroid function is not an important determit of hypertension in elderly Dutch subjects. Thyroid hormone is essential for the normal function of virtually all tissues. The iodothyronine deiodinases catalyze the removal of an iodine residue from the pro-hormone thyroxine (T(4)) molecule, thus producing either the active form triiodothyronine (T(3); activation) or inactive metabolites (reverse T(3); inactivation). Type I deiodinase (D1) catalyzes both reactions. Over the last years, several studies have attempted to understand the mechanisms of D1 function, underlying its effects on normal thyroid hormone metabolism and pathological processes. Although peripheral D1-generated T(3) production contributes to a portion of plasma T(3) in euthyroid state, pathologically increased thyroidal D1 activity seems to be the main cause of the elevated T(3) concentrations observed in hyperthyroid patients. On the other hand, D1-deficient mouse models show that, in the absence of D1, inactive and lesser iodothyronines are excreted in feces with the loss of associated iodine, demonstrating the scavenging function for D1 that might be particularly important in an iodine deficiency setting. Polymorphisms in the DIO1 gene have been associated with changes in serum thyroid hormone levels, whereas decreased D1 activity has been reported in the nonthyroid illness syndrome and in several human neoplasias. The current review aims at presenting an updated picture of the recent advances made in the biochemical and molecular properties of D1 as well as its role in human physiology.

At which kind of individuals is pharmacological treatment of subclinical hypothyroidism effective in reducing cardiovascular events?

Treatment of subclinical hypothyroidism is associated with fewer cardiovascular events in younger individuals, but this issue has not been resolved yet in elderly people.

Subclinical hypothyroidism (SH), defined by elevated serum levels of thyroid stimulating hormone (TSH) with normal levels of free thyroid hormones, is common in adults, especially in women over 60 years of age. Among individuals with this condition, up to two-thirds have serum TSH levels between 5-10 mU/L and thyroid autoantibodies; almost half of them may progress to overt thyroid failure, the annual percent risk increasing with serum TSH level. There is evidence that elevated TSH levels in patients with SH do not reflect pituitary compensation to maintain euthyroidism, but a mild tissue hypothyroidism sensu strictu. When lasting more than 6-12 months, SH may be associated with an atherogenic lipid profile, a hypercoagulable state, a subtle cardiac defect with mainly diastolic dysfunction, impaired vascular function, and reduced submaximal exercise capacity. The deviation from normality usually increases with serum TSH level ('dosage effect' phenomenon). Restoration of euthyroidism by levothyroxine (LT4) treatment may correct the lipid profile and cardiac abnormalities, especially in patients with an initially higher deviation from normality and higher serum TSH levels. Importantly, a strong association between SH and atherosclerotic cardiovascular disease, independent of the traditional risk factors, has been recently reported in a large cross-sectional survey (the Rotterdam Study). However, whether SH confers a high risk for cardiovascular disease, and whether LT4 therapy has a long-term benefit that clearly outweighs the risks of overzealous treatment in these individuals, remain topics of controversy. Therefore, until randomized, controlled, prospective, and adequately powered trials provide unequivocal answers to these critical questions, it is advisable to prescribe LT4 therapy on a case-by-case basis, taking into account the risk of progressive thyroid failure and the risk of cardiovascular events. Subclinical hypothyroidism is defined as an elevated serum thyroid-stimulating hormone (TSH) level in the face of normal free thyroid hormone values. The overall prevalence of subclinical hypothyroidism is 4-10% in the general population and up to 20% in women aged >60 years. The potential benefits and risks of therapy for subclinical hypothyroidism have been debated for 2 decades, and a consensus is still lacking. Besides avoiding the progression to overt hypothyroidism, the decision to treat patients with subclinical hypothyroidism relies mainly on the risk of metabolic and cardiovascular alterations. Subclinical hypothyroidism causes changes in cardiovascular function similar to, but less marked than, those occurring in patients with overt hypothyroidism. Diastolic dysfunction both at rest and upon effort is the most consistent cardiac abnormality in patients with subclinical hypothyroidism, and also in those with slightly elevated TSH levels (>6 mIU/L). Moreover, mild thyroid failure may increase diastolic blood pressure as a result of increased systemic vascular resistance. Restoration of euthyroidism by levothyroxine replacement is generally able to improve all these abnormalities. Early clinical and autopsy studies had suggested an association between subclinical hypothyroidism and coronary heart disease, which has been subsequently confirmed by some, but not all, large cross-sectional and prospective studies. Altered coagulation parameters, elevated lipoprotein (a) levels, and low-grade chronic inflammation are regarded to coalesce with the hypercholesterolemia of untreated patients with subclinical hypothyroidism to enhance the ischemic cardiovascular risk. Although a consensus is still lacking, the strongest evidence for a beneficial effect of levothyroxine replacement on markers of cardiovascular risk is the substantial demonstration that restoration of euthyroidism can lower both total and low-density lipoprotein-cholesterol levels in most patients with subclinical hypothyroidism. However, the actual effectiveness of thyroid hormone substitution in reducing the risk of cardiovascular events remains to be elucidated. In conclusion, the multiplicity and the possible reversibility of subclinical hypothyroidism-associated cardiovascular abnormalities suggest that the decision to treat a patient should depend on the presence of risk factors, rather than on a TSH threshold. On the other hand, levothyroxine replacement therapy can always be discontinued if there is no apparent benefit. Levothyroxine replacement therapy is usually safe providing that excessive administration is avoided by monitoring serum TSH levels. However, the possibility that restoring euthyroidism may be harmful in the oldest of the elderly population of hypothyroid patients has been recently raised, and should be taken into account in making the decision to treat patients with subclinical hypothyroidism who are aged >85 years. BACKGROUND: Subclinical hypothyroidism is defined as an elevated serum thyroid-stimulating hormone (TSH) level with normal free thyroid hormones values. The prevalence of subclinical hypothyroidism is 4% to 8% in the general population, and up to 15% to 18% in women who are over 60 years of age. There is considerable controversy regarding the morbidity, the clinical significance of subclinical hypothyroidism and if these patients should be treated. OBJECTIVES: To assess the effects of thyroid hormone replacement for subclinical hypothyroidism. SEARCH STRATEGY: We searched The Cochrane Library, MEDLINE, EMBASE and LILACS. Ongoing trials databases, reference lists and abstracts of congresses were scrutinized as well. SELECTION CRITERIA: All studies had to be randomised controlled trials comparing thyroid hormone replacement with placebo or no treatment in adults with subclinical hypothyroidism. Minimum duration of follow-up was one month. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. We contacted study authors for missing or additional information. MAIN RESULTS: Twelve trials of six to 14 months duration involving 350 people were included. Eleven trials investigated levothyroxine replacement with placebo, one study compared levothyroxine replacement with no treatment. We did not identify any trial that assessed (cardiovascular) mortality or morbidity. Seven studies evaluated symptoms, mood and quality of life with no statistically significant improvement. One study showed a statistically significant improvement in cognitive function. Six studies assessed serum lipids, there was a trend for reduction in some parameters following levothyroxine replacement. Some echocardiographic parameters improved after levothyroxine replacement therapy, like myocardial relaxation, as indicated by a significant prolongation of the isovolumic relaxation time as well as diastolic dysfunction. Only four studies reported adverse events with no statistically significant differences between groups. AUTHORS' CONCLUSIONS: In current RCTs, levothyroxine replacement therapy for subclinical hypothyroidism did not result in improved survival or decreased cardiovascular morbidity. Data on health-related quality of life and symptoms did not demonstrate significant differences between intervention groups. Some evidence indicates that levothyroxine replacement improves some parameters of lipid profiles and left ventricular function. BACKGROUND: Some studies have proposed that subclinical hypothyroidism (SCH) has adverse effects on the cardiovascular system, but little is known about the effect on patients undergoing cardiovascular operations. We examined the influence of preoperative SCH on postoperative outcome in patients undergoing coronary artery bypass grafting (CABG). METHODS: Among patients who underwent CABG between July 2005 and June 2007 at Seoul National University Bundang Hospital, 224 with normal thyroid function and 36 with SCH were enrolled. Preoperative risks and postoperative outcomes were evaluated prospectively without thyroid hormone replacement. RESULTS: There were no significant differences in primary outcomes (major adverse cardiovascular events) and secondary outcomes such as wound problems, mediastinitis, leg infection, respiratory complications, delirium, or reoperation during the same hospitalization. However, patients with SCH had a higher incidence of postoperative atrial fibrillation than those with normal thyroid function after adjustment for age, gender, body mass index, and other independent variables such as emergency operation, the use of cardiopulmonary bypass, combined valvular operation, preoperative creatinine levels, left ventricular systolic dysfunction, and nonuse of beta-blockers (45.5% vs 29%; odds ratio, 2.552; 95% confidence interval, 1.117 to 5.830; p = 0.026). CONCLUSIONS: SCH appears to influence the postoperative outcome for patients by increasing the development of postoperative atrial fibrillation. However, it is still unproven whether preoperative thyroxine replacement therapy for patients with SCH might prevent postoperative atrial fibrillation after CABG.

Is intense physical activity associated with longevity?

YES:

OBJECTIVE: To compare the long term survival of a group of athletes taking prolonged vigorous physical exercise to that of the general population. DESIGN: Follow up of a cohort of participants in the Dutch eleven cities ice skating tour (a race and recreational tour) over a distance of 200 kilometers. SETTING: Data on participation from the organising committee and data on mortality from all municipalities in The Netherlands. SUBJECTS: 2259 Male athletes. MAIN OUTCOME MEASURES: Comparison of all cause mortality in male participants in the tour with that in the general population of The Netherlands. RESULTS: The standardised mortality ratio for all participants during 32 years of follow up was 0.76 (95% confidence interval 0.68 to 0.85), and 0.90 (0.48 to 1.44) for participants in the race, and 0.72 (0.60 to 0.86) for participants in the recreational tour who finished within the time limit. CONCLUSIONS: The capacity for prolonged and vigorous physical exercise, particularly if the exercise is recreational, is a strong indicator of longevity. Physical activity is associated with better health; however, the optimal intensity of activity remains unclear. A total of 13,485 men (mean age, 57.5 years) from the Harvard Alumni Health Study reported their walking, stair climbing, and sports/recreation in 1977. Between 1977 and 1992, 2,539 died. After adjusting for the different activity components, distance walked and storeys climbed independently predicted longevity (p, trend = 0.004 and <0.001, respectively). Light activities (<4 multiples of resting metabolic rate (METs)) were not associated with reduced mortality rates, moderate activities (4-<6 METs) appeared somewhat beneficial, and vigorous activities (> or =6 METs) clearly predicted lower mortality rates (p, trend = 0.72, 0.07, and <0.001, respectively). These data provide some support for current recommendations that emphasize moderate intensity activity; they also clearly indicate a benefit of vigorous activity. Longitudinal observations on the sports play, social habits and health status of 52,000 men who entered Harvard College or the University of Pennsylvania between 1916 and 1950 have afforded means of identifying causes of disease and death. These observations were then translated into the eff ect of sports and physical exercise on health and longevity. Student sports play in college predicted a decreased risk of developing cardiovascular disease (CVD) at least up to age 50 years. Questionnaire surveys showed physical exercise (sports play, walking and stair climbing) in middle age to be inversely related to the later development of CVD and early death. In a 10-year follow-up between 1962 and 1972, alumni aged 35-74 years who expended greater than or equal to ≥ 2000 kcal week(-1) (8.4 MJ week -1 ) in such activities had a 25% reduced risk of CVD and death compared with less active men. But, the 'protective eff ect' of early athleticism waned unless a physically active life was maintained. In contrast, sedentary students who took up an active life were at a lower risk of CVD and death than former student athletes who gave up or reduced their physical activities in middle age. A total of 17,815 Harvard alumni aged 45-84 years were followed from a 1977 questionnaire survey through 1992, with 4399 deaths occurring. Death rates declined with increased levels of total activity (estimated in kilocalories), and declined also with increased intensity of effort measured as from none, to light, to moderately vigorous or vigorous sports play. Death rates at any given quantity of physical exercise were lower for men playing moderately intense sports than for less vigorous men. Over the age range, in the 16-year follow-up, Harvard alumni playing moderately vigorous or more intense sports gained 1.5 years by age 90 compared with less active men.

How homoplasy affects phylogenetic reconstruction?

Evolutionary processes create both newly derived characteristics shared by related descendant lineages (homology) and "false" similarities which confound phylogenetic reconstruction (homoplasy). Homology arises by divergent evolution from a common ancestor and provides us with a phylogenetic signal, while homoplasy arises by convergent evolution or random coincidence. Homoplastic characters do not allows branch points and clade membership to be accurately estimated, as they may group unrelated taxa together. Such characters add "noise" in phylogenetic analysis and are not informative for the population genetics and the phylogenetic reconstruction of closely related taxa. In phylogenetic reconstruction, homoplasy leads to inaccurate conclusions about phylogenetic relationships among operational taxonomic units, and characters with high degree of homoplasy result in incongruences of cladistic relationships.

DNA hybridization is a "distance method" for phylogenetic reconstruction and, as such, shares a set of assumptions, advantages, and problems with other techniques that do not directly employ character data. The technique purports to measure the average percent mismatch of homologous nucleotide sequences between the single-copy genomes of species. This measurement, as any other, is subject to considerations of accuracy and precision. While replicate measurements and technical modifications can improve precision, the accuracy of such measurements is limited by the equivalence of genomes under comparison. Such routine events in genome evolution as gene duplication and deletion may complicate the interpretation of DNA hybridization distances. Beyond measurement limitations, the most serious potential distortions of distances are due to biased sequence sampling and homoplasy. These problems, however, do not necessarily preclude phylogenetic reconstruction, and their effects may be mitigated by numerical corrections. Homoplasy, in particular, is a difficulty faced by all methods of phylogenetic inference. If such distortions can be eliminated, mitigated by correction, or shown to be trivial, pairwise tree-construction strategies should provide reliable estimates of phylogeny. Molecular evolutionary processes modify DNA over time, creating both newly derived substitutions shared by related descendant lineages (phylogenetic signal) and "false" similarities which confound phylogenetic reconstruction (homoplasy). However, some types of DNA regions, for example those containing tandem duplicate repeats, are preferentially subject to homoplasy-inducing processes such as sporadically occurring concerted evolution and DNA insertion/deletion. This added level of homoplasic "noise" can make DNA regions with repeats less reliable in phylogenetic reconstruction than those without repeats. Most molecular datasets which distinguish among African hominoids support a human-chimpanzee clade; the most notable exception is from the involucrin gene. However, phylogenetic resolution supporting a chimpanzee-gorilla clade is based entirely on involucrin DNA repeat regions. This is problematic because (1) involucrin repeats are difficult to align, and published alignments are contradictory; (2) involucrin repeats are subject to DNA insertion/deletion; (3) gorillas are polymorphic in that some do not have repeats reported to be synapomorphies linking chimpanzees and gorillas. Gene tree/species tree conflicts can occur due to the sorting of ancestrally polymorphic alleles during speciation. Because hominoid females transfer between groups, mitochondrial and nuclear gene flow occur to the same extent, and the probability of conflict between mitochondrial and nuclear gene trees is theoretically low. When hominoid intraspecific mitochondrial variability is taken into account [based on cytochrome oxidase subunit II (COII) gene sequences], humans and chimpanzees are most closely related, showing the same relative degree of separation from gorillas as when single individuals representing species are analyzed. Conflicting molecular phylogenies can be explained in terms of molecular evolutionary processes and sorting of ancient polymorphisms. This perspective can enhance our understanding of hominoid molecular phylogenies. The species diversity of the phylum Rotifera has been largely studied on the basis of morphological characters. However, cladistic relationships within this group are poorly resolved due to extensive homoplasy in morphological traits, substantial phenotypic plasticity and a poor fossil record. We undertook this study to determine if a phylogeny based on partial 18S rDNA, which included the helix E23 of 18S rDNA sequence, was concordant with established taxonomic relationships within the order Ploimida (class: Monogononta). We also estimated the level of polymorphism within clones and populations of Ploimida 'species'. Finally, we included the Cycliophora Symbion pandora as outgroup and the variable helix E23 region to examine the influence of their signal on the evolutionary relationships among Acanthocephala, Bdelloidea and Ploimida. Phylogenetic reconstruction was performed using maximum parsimony, neighbour joining and maximum likelihood methods. We found 1) that morphologically similar Ploimida 'species' show vastly different 18S E23 rDNA sequences; 2) inclusion of the helix E23 of 18S rDNA and its secondary structure analysis results in better resolution of family level relationships within the Ploimida; 3) an impact of Symbion pandora as an outgroup with inclusion of the helix E23 on the relationships between the Rotifera and the Acanthocephala; and 4) partial incongruence and differential substitution rate between conserved region and helix E23 region of the 18S rDNA gene depending on the taxomic group studied. Early hominid masticatory characters are widely considered to be more prone to homoplasy than characters from other regions of the early hominid skull and therefore less reliable for phylogenetic reconstruction. This hypothesis has important implications for current reconstructions of early hominid phylogeny, but it has never been tested. In this paper we evaluate the likely veracity of the hypothesis using craniometric data from extant primate groups for which reliable consensus molecular phylogenies are available. Datasets representing the extant large-bodied hominoid genera and the extant papionin genera were compiled from standard measurements. The data were adjusted to minimise the confounding effects of body size, and then converted into discrete character states using divergence coding. Each dataset was divided into four regional character groups: (1) palate and upper dentition, (2) mandible and lower dentition, (3) face and (4) cranial vault and base. Thereafter, the regional character groups were analysed using cladistic methods and the resulting phylogenetic hypotheses judged against the consensus molecular phylogenies for the hominoids and papionins. The analyses indicated that the regions dominated by masticatory characters-the palate and upper dentition, and the mandible and lower dentition-are no less reliable for phylogenetic reconstruction than the other regions of the skull. The four regions were equally affected by homoplasy and were, therefore, equally unreliable for phylogenetic reconstruction. This finding challenges the recent suggestion that Paranthropus is polyphyletic, which is based on the assumption that masticatory characters are especially prone to homoplasy. Our finding also suggests that, contrary to current practice, there is no a priori reason to de-emphasise the phylogenetic significance of the masticatory similarities between Homo rudolfensis and the australopiths. The corollary of this is that H. rudolfensis is unlikely to be a member of the Homo clade and should therefore be allocated to another genus. Nucleotide transitions are frequently down-weighted relative to transversions in phylogenetic analysis. This is based on the assumption that transitions, by virtue of their greater evolutionary rate, exhibit relatively more homoplasy and are therefore less reliable phylogenetic characters. Relative amounts of homoplastic and consistent transition and transversion changes in mitochondrial protein coding genes were determined from character-state reconstructions on a highly corroborated phylogeny of mammals. We found that although homoplasy was related to evolutionary rates and was greater for transitions, the absolute number of consistent transitions greatly exceeded the number of consistent transversions. Consequently, transitions provided substantially more useful phylogenetic information than transversions. These results suggest that down-weighting transitions may be unwarranted in many cases. This conclusion was supported by the fact that a range of transition: transversion weighting schemes applied to various mitochondrial genes and genomic partitions rarely provided improvement in phylogenetic estimates relative to equal weighting, and in some cases weighting transitions more heavily than transversions was most effective. Phylogenetic reconstruction using molecular data is often subject to homoplasy, leading to inaccurate conclusions about phylogenetic relationships among operational taxonomic units. Compared with other molecular markers, single-nucleotide polymorphisms (SNPs) exhibit extremely low mutation rates, making them rare in recently emerged pathogens, but they are less prone to homoplasy and thus extremely valuable for phylogenetic analyses. Despite their phylogenetic potential, ascertainment bias occurs when SNP characters are discovered through biased taxonomic sampling; by using whole-genome comparisons of five diverse strains of Bacillus anthracis to facilitate SNP discovery, we show that only polymorphisms lying along the evolutionary pathway between reference strains will be observed. We illustrate this in theoretical and simulated data sets in which complex phylogenetic topologies are reduced to linear evolutionary models. Using a set of 990 SNP markers, we also show how divergent branches in our topologies collapse to single points but provide accurate information on internodal distances and points of origin for ancestral clades. These data allowed us to determine the ancestral root of B. anthracis, showing that it lies closer to a newly described "C" branch than to either of two previously described "A" or "B" branches. In addition, subclade rooting of the C branch revealed unequal evolutionary rates that seem to be correlated with ecological parameters and strain attributes. Our use of nonhomoplastic whole-genome SNP characters allows branch points and clade membership to be estimated with great precision, providing greater insight into epidemiological, ecological, and forensic questions. Species-level phylogenetic studies require fast-evolving nucleotide positions to resolve relationships among close relatives, but these sites may be highly homoplastic and perhaps uninformative or even misleading deeper in the tree. Here we describe a species-level analysis of tiger beetles in the genus Cicindela (Coleoptera: Cicindelidae) for 132 terminal taxa and 1897 nucleotide positions from three regions of mtDNA, comprising 75% coverage of species occurring in North America. Evenly weighted parsimony analysis recovered four major clades representing radiations confined to North and Central America. Relationships near the tips were well supported but signal was contradictory at deeper nodes. Two major categories (3rd positions and all others) can be distinguished in likelihood analysis of character variation, of which only the fast-changing 3rd position characters were affected by saturation. However, their downweighting under a variety of criteria did not improve the tree topology at basal nodes. There was weak conflict between 3rd and non-3rd position characters deep in the tree, but support levels declined towards the root for all categories, even on trees that were reconstructed from 3rd and non-3rd positions separately. Statistical analysis of parsimony-based character transitions along branches showed a largely homogeneous distribution of change along the root-to-tip axis. The comparison of character transitions among the four major portions of the tree revealed deviations from stochastic distribution for the non-3rd positions, but not for 3rd positions. Hence, variability of functionally constrained non-3rd positions differs between clades and may be dependent on the character states at other sites, consistent with the covarion model of molecular evolution. The results suggest that some properties of 3rd positions are less problematic for phylogenetic reconstruction than other categories despite their high total homoplasy. In densely sampled data sets of closely related species, the disadvantages of weighting schemes according to homoplasy levels outweigh the benefits, showing the difficulty of devising meaningful weighting schemes that are applicable universally throughout the tree. During phylogenetic analysis of the Nepenthaceae cpDNA trnK intron, it became apparent that a second non-functional copy of the locus was present in most of the investigated taxa. The translocation event was older than the radiation of all recent Nepenthaceae, and the translocated pseudogenized copy was conserved in nearly all members of the plant family. Using single chloroplast PCR and inverse PCR, we could exclude a plastom location for the second copy. Although translocation into the nucleus is possible, mitochondrial localization seems more likely based on these data. In total, the translocated sequence contained at least 3525 base pairs (bp) that were homologous to the Spinacia oleracea chloroplast genome. Comparative phylogenetic analysis of the non-functional copy revealed a high amount of homoplasies compared to topologies from the cpDNA trnK intron phylogenetic reconstruction. Therefore, this copy proved to be insufficient for phylogenetic reconstruction of the family. Since two different paralogs of the non-functional copy were found in one species, it is feasible that different paralogs were conserved in different groups and that paralogous sequences were included in the data matrix. These data demonstrate that phylogenetic analyses of pseudogenized copies of phylogenetically relevant loci should be performed with great caution. In addition, pseudogenized copies can exist in nearly every member of a plant family, and can be PCR-amplified at levels comparable to the specific copy. In this case, the inclusion of such copies can easily remain unnoticed, thus leading to faulty hypotheses. Phylogenetic reconstructions are often plagued by difficulties in distinguishing phylogenetic signal (due to shared ancestry) from phylogenetic noise or homoplasy (due to character-state convergences or reversals). We use a new interpretive hypothesis, termed hemiplasy, to show how random lineage sorting might account for specific instances of seeming "phylogenetic discordance" among different chromosomal traits, or between karyotypic features and probable species phylogenies. We posit that hemiplasy is generally less likely for underdomit chromosomal polymorphisms (i.e., those with heterozygous disadvantage) than for neutral polymorphisms or especially for overdomit rearrangements (which should tend to be longer-lived), and we illustrate this concept by using examples from chiropterans and afrotherians. Chromosomal states are especially powerful in phylogenetic reconstructions because they offer strong signatures of common ancestry, but their evolutionary interpretations remain fully subject to the principles of cladistics and the potential complications of hemiplasy. Distinguishing phylogenetic signal from homoplasy (shared similarities among taxa that do not arise by common ancestry) is an implicit goal of any phylogenetic study. Large amounts of homoplasy can interfere with accurate tree inference, and it is expected that common measures of clade support, including bootstrap proportions and Bayesian posterior probabilities, should also be impacted to some degree by homoplasy. Through data simulation and analysis of 38 empirical data sets, we show that high amounts of homoplasy will affect all measures of clade support in a manner that is dependent on clade size. More specifically, the smallest taxon bipartitions in an unrooted tree topology will receive higher support relative to clades of intermediate sizes, even when all clades are supported by the same amount of data. We determine that the ultimate causes of this effect are the inclusion of random trees (due to homoplasy) during bootstrap resampling and Markov chain Monte Carlo (MCMC) topology searching and the higher relative proportion of small taxon bipartitions (i.e., 2 or 3 taxa) to larger sized bipartitions. However, the use of explicit model-based methods, especially Bayesian MCMC methods, effectively overcomes this clade size effect even when very small amounts of phylogenetic signal are present. We develop a post hoc statistic, the clade disparity index (CDI), to measure both the relative magnitude of the clade size effect and its statistical significance. In analyses of both simulated and empirical data, CDI values indicate that Bayesian MCMC analyses are substantially more likely to estimate clade support values that are uncorrelated with clade size than are maximum parsimony and maximum likelihood bootstrap analyses and thus less affected by homoplasy. These results may be especially relevant to "deep" phylogenetic problems, such as reconstructing the tree of life, as they represent the largest possible extremes of time and evolutionary rates, 2 factors that cause homoplasy. The objective was to apply a novel modification of a genome-wide, comparative cytogenetic technique (comparative genomic hybridization, comparative genomic hybridization (CGH)), to study species belonging to the myrmecophagous (ant/termite eating) mammalian orders/superorders (Pholidota, Tubulidentata, Carnivora, and Xenarthra), as a model for other applications in mammalian systematics and conservation biology. In this study, CGH was applied to high-quality metaphase spreads of pangolin (Pholidota), using probes of sloth and canine (Xenarthra and Carnivora, respectively) genomic DNA labeled with different fluorophores, thereby facilitating analysis of the visible color spectrum on pangolin karyotypes. Our results posited that pholidotes are closer to carnivores than to xenarthrans, which confirmed the current consensus that myrmecophagy in these mammalian lineages was more likely because of homoplasy (convergent evolution) than being an ancestral character. Since the modified CGH technique used is genome-wide, has chromosome-level resolution, and does not need full genome sequencing, it has considerable potential in systematics and other fields. Understanding the evolutionary history of species is at the core of molecular evolution and is done using several inference methods. The critical issue is to quantify the uncertainty of the inference. The posterior probabilities in Bayesian phylogenetic inference and the bootstrap values in frequentist approaches measure the variability of the estimates due to the sampling of sites from genes and the sampling of genes from genomes. However, they do not measure the uncertainty due to taxon sampling. Taxa that experienced molecular homoplasy, recent selection, a spur of evolution, and so forth may disrupt the inference and cause incongruences in the estimated phylogeny. We define a taxon influence index to assess the influence of each taxon on the phylogeny. We found that although most taxa have a weak influence on the phylogeny, a small fraction of influential taxa strongly alter it even in clades only loosely related to them. We conclude that highly influential taxa should be given special attention and sampling them more thoroughly can lead to more dependable phylogenies. Since its discovery in the early 2000s, methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) has become a rapidly emerging cause of human infections, most often associated with livestock exposure. We applied whole-genome sequence typing to characterize a diverse collection of CC398 isolates (n = 89), including MRSA and methicillin-susceptible S. aureus (MSSA) from animals and humans spanning 19 countries and four continents. We identified 4,238 single nucleotide polymorphisms (SNPs) among the 89 core genomes. Minimal homoplasy (consistency index = 0.9591) was detected among parsimony-informative SNPs, allowing for the generation of a highly accurate phylogenetic reconstruction of the CC398 clonal lineage. Phylogenetic analyses revealed that MSSA from humans formed the most ancestral clades. The most derived lineages were composed predomitly of livestock-associated MRSA possessing three different staphylococcal cassette chromosome mec element (SCCmec) types (IV, V, and VII-like) including nine subtypes. The human-associated isolates from the basal clades carried phages encoding human innate immune modulators that were largely missing among the livestock-associated isolates. Our results strongly suggest that livestock-associated MRSA CC398 originated in humans as MSSA. The lineage appears to have undergone a rapid radiation in conjunction with the jump from humans to livestock, where it subsequently acquired tetracycline and methicillin resistance. Further analyses are required to estimate the number of independent genetic events leading to the methicillin-resistant sublineages, but the diversity of SCCmec subtypes is suggestive of strong and diverse antimicrobial selection associated with food animal production. IMPORTANCE: Modern food animal production is characterized by densely concentrated animals and routine antibiotic use, which may facilitate the emergence of novel antibiotic-resistant zoonotic pathogens. Our findings strongly support the idea that livestock-associated MRSA CC398 originated as MSSA in humans. The jump of CC398 from humans to livestock was accompanied by the loss of phage-carried human virulence genes, which likely attenuated its zoonotic potential, but it was also accompanied by the acquisition of tetracycline and methicillin resistance. Our findings exemplify a bidirectional zoonotic exchange and underscore the potential public health risks of widespread antibiotic use in food animal production. Copepods are a diverse and ecologically crucial group of minute crustaceans that are relatively neglected in terms of studies on nervous system organization. Recently, morphological neural characters have helped clarify evolutionary relationships within Arthropoda, particularly among Tetraconata (i.e., crustaceans and hexapods), and indicate that copepods occupy an important phylogenetic position relating to both Malacostraca and Hexapoda. This taxon therefore provides the opportunity to evaluate those neural characters common to these two clades likely to be results of shared ancestry (homology) versus convergence (homoplasy). Here we present an anatomical characterization of the brain and central nervous system of the well-studied harpacticoid copepod species Tigriopus californicus. We show that this species is endowed with a complex brain possessing a central complex comprising a protocerebral bridge and central body. Deutocerebral glomeruli are supplied by the antennular nerves, and a lateral protocerebral olfactory neuropil corresponds to the malacostracan hemiellipsoid body. Glomeruli contain synaptic specializations comparable to the presynaptic "T-bars" typical of dipterous insects, including Drosophila melanogaster. Serotonin-like immunoreactivity pervades the brain and ventral nervous system, with distinctive deutocerebral distributions. The present observations suggest that a suite of morphological characters typifying the Tigriopus brain reflect a ground pattern organization of an ancestral Tetraconata, which possessed an elaborate and structurally differentiated nervous system. In this study, we analyse the evolutionary dynamics and phylogenetic implications of gene order rearrangements in five newly sequenced mitochondrial (mt) genomes and four published mt genomes of isopod crustaceans. The sequence coverage is nearly complete for four of the five newly sequenced species, with only the control region and some tRNA genes missing, while in Janira maculosa only two thirds of the genome could be determined. Mitochondrial gene order in isopods seems to be more plastic than that in other crustacean lineages, making all nine known mt gene orders different. Especially the asellote Janira is characterized by many autapomorphies. The following inferred ancestral isopod mt gene order exists slightly modified in modern isopods: nad1, tnrL1, rrnS, control region, trnS1, cob, trnT, nad5, trnF. We consider the inferred gene translocation events leading to gene rearrangements as valuable characters in phylogenetic analyses. In this first study covering major isopod lineages, potential apomorphies were identified, e.g., a shared relative position of trnR in Valvifera. We also report one of the first findings of homoplasy in mitochondrial gene order, namely a shared relative position of trnV in unrelated isopod lineages. In addition to increased taxon sampling secondary structure, modification in tRNAs and GC-skew inversion may be potentially fruitful subjects for future mt genome studies in a phylogenetic context. The Euro-American lineage of the Mycobacterium tuberculosis complex consists of 10 sublineages, each defined by a deletion of a large genomic region (RD, region of difference); by spoligotyping, that probes the polymorphism of the Direct Repeat (DR) locus, the Euro-American strains are classified into 5 lineages (T, Haarlem, LAM, S and X) and 34 sublineages, but the relationships between the RD-defined sublineages and the spoligotype groupings are largely unclear. By testing a global sample of 158 Euro-American strains, mutually exclusive deletions of RD115, RD122, RD174, RD182, RD183, RD193, RD219, RD726 or RD761 were found in 122 strains; deletion of RD724, typical of strains from Central Africa, was not found. The RD-defined sublineages, tested for katG463/gyrA95 polymorphism, belonged to Principal Genotypic Group (PGG) 2, with the exception of RD219 sublineage belonging to PGG3; the 36 strains with no deletion were of either PGG2 or 3. Based on these polymorphisms, a phylogenetic reconstruction of the Euro-American lineage, that integrates the previously reported phylogeny, is proposed. Although certain deletions were found to be associated to certain spoligotype lineages (i.e., deletion RD115 to T and LAM, RD174 to LAM, RD182 to Haarlem, RD219 to T), our analysis indicates a general lack of concordance between RD-defined sublineages and spoligotype groupings. Moreover, of the 42 spoligotypes detected among the study strains, sixteen were shared by strains belonging to different RD sublineages. IS6110-RFLP analysis of strains sharing spoligotypes confirmed a poor genetic relatedness between strains of different RD sublineages. These findings provide evidence for the occurrence of a high degree of homoplasy in the DR locus leading to convergent evolution to identical spoligotypes. The incongruence between Large Sequence Polymorphism and spoligotype polymorphism argues against the use of spoligotyping for establishing phylogenetic relationships within the Euro-American lineage. Bcl-2 family proteins regulate apoptosis in animals. This protein family includes several homologous proteins and a collection of other proteins lacking sequence similarity except for a Bcl-2 homology (BH)3 motif. Thus, membership in the Bcl-2 family requires only one of the four BH motifs. On this basis, a growing number of diverse BH3-only proteins are being reported. Although compelling cell biological and biophysical evidence validates many BH3-only proteins, claims of significant BH3 sequence similarity are often unfounded. Computational and phylogenetic analyses suggest that only some BH3 motifs arose by divergent evolution from a common ancestor (homology), whereas others arose by convergent evolution or random coincidence (homoplasy), challenging current assumptions about which proteins constitute the extended Bcl-2 family. Conflict among data sources can be frequent in evolutionary biology, especially in cases where one character set poses limitations to resolution. Earthworm taxonomy, for example, remains a challenge because of the limited number of morphological characters taxonomically valuable. An explanation to this may be morphological convergence due to adaptation to a homogeneous habitat, resulting in high degrees of homoplasy. This sometimes impedes clear morphological diagnosis of species. Combination of morphology with molecular techniques has recently aided taxonomy in many groups difficult to delimit morphologically. Here we apply an integrative approach by combining morphological and molecular data, including also some ecological features, to describe a new earthworm species in the family Hormogastridae, Hormogaster abbatissaesp. n., collected in Sant Joan de les Abadesses (Girona, Spain). Its anatomical and morphological characters are discussed in relation to the most similar Hormogastridae species, which are not the closest species in a phylogenetic analysis of molecular data. Species delimitation using the GMYC method and genetic divergences with the closest species are also considered. The information supplied by the morphological and molecular sources is contradictory, and thus we discuss issues with species delimitation in other similar situations. Decisions should be based on a profound knowledge of the morphology of the studied group but results from molecular analyses should also be considered. Molecular methods have been used for the first time to determine the phylogeny of families, genera and species within the Pennatulacea (sea pens). Variation in ND2 and mtMutS mitochondrial protein-coding genes proved adequate to resolve phylogenetic relationships among pennatulacean families. The gene mtMutS is more variable than ND2 and differentiates all genera, and many pennatulacean species. A molecular phylogeny based on a Bayesian analysis reveals that suborder Sessiliflorae is paraphyletic and Subselliflorae is polyphyletic. Many families of pennatulaceans do not represent monophyletic groups including Umbellulidae, Pteroeididae, and Kophobelemnidae. The high frequency of morphological homoplasy in pennatulaceans has led to many misinterpretations in the systematics of the group. The traditional classification scheme for pennatulaceans requires revision. Rate of substitution of genomic regions is among the most debated intrinsic features that impact phylogenetic informativeness. However, this variable is also coupled with rates of nonsynonymous substitutions that underscore the nature and degree of selection on the selected genes. To empirically address these variables, we constructed four completely overlapping data sets of plastid matK, atpB, rbcL, and mitochondrial matR genes and used the rosid lineage (angiosperms) as a working platform. The genes differ in combinations of overall rates of nucleotide and amino acid substitutions. Tree robustness, homoplasy, accuracy in contrast to a reference tree, and phylogenetic informativeness are evaluated. The rapidly evolving/unconstrained matK faired best, whereas remaining genes varied in degrees of contribution to rosid phylogenetics across the lineage's 108 million years evolutionary history. Phylogenetic accuracy was low with the slowly evolving/unconstrained matR despite least amount of homoplasy. Third codon positions contributed the highest amount of parsimony informative sites, resolution and informativeness, but magnitude varied with gene mode of evolution. These findings are in clear contrast with the views that rapidly evolving regions and the 3rd codon position have inevitable negative impact on phylogenetic reconstruction at deep historic level due to accumulation of multiple hits and subsequent elevation in homoplasy and saturation. Relaxed evolutionary constraint in rapidly evolving genes distributes substitutions across codon positions, an evolutionary mode expected to reduce the frequency of multiple hits. These findings should be tested at deeper evolutionary histories.

What is known about the association between the use of selective serotonin reuptake inhibitors during pregnancy and risk for autism in offspring?

Greater risk for autism spectrum disorders has been reported among mothers that have used selective serotonin reuptake inhibitors during pregnancy. However, others did not find an association between the use of selective serotonin reuptake inhibitors during pregnancy and risk for autism in offspring. Also, selective serotonin reuptake inhibitor use during pregnancy were associated with a greater number of gastrointestinal complaints in children with autism spectrum disorders.

Selective serotonin reuptake inhibitors (SSRIs), such as citalopram (CTM), have been widely prescribed for major depressive disorder, not only for adult populations, but also for children and pregt mothers. Recent evidence suggests that chronic SSRI exposure in adults increases serotonin (5-HT) levels in the raphe system and decreases norepinephrine (NE) locus ceruleus (LC) neural activity, suggesting a robust opposing interaction between these two monoamines. In contrast, perinatal SSRI exposure induces a long-lasting downregulation of the 5-HT-raphe system, which is opposite to that seen with chronic adult treatment. Therefore, the goal of the present investigation was to test the hypothesis that perinatal CTM exposure (20 mg/kg/d) from postnatal day 1 (PN1) to PN10 leads to hyperexcited NE-LC circuit function in adult rats (>PN90). Our single-neuron LC electrophysiological data demonstrated an increase in spontaneous and stimulus-driven neural activity, including an increase in phasic bursts in CTM-exposed animals. In addition, we demonstrated a corresponding immunoreactive increase in the rate-limiting catalyzing catecholamine enzyme (tyrosine hydroxylase) within the LC and their neocortical target sites compared to saline controls. Moreover, these effects were only evident in male exposed rats, suggesting a sexual dimorphism in neural development after SSRI exposure. Together, these results indicate that administration of SSRIs during a sensitive period of brain development results in long-lasting alterations in NE-LC circuit function in adults and may be useful in understanding the etiology of pervasive developmental disorders such as autism spectrum disorder. Serotonin, a neurotransmitter found throughout the brain and body, has long been of interest in autism. Repeated findings of elevated platelet serotonin levels in approximately one third of children with autism has led some to believe that dysfunctional serotonin signaling may be a causal mechanism for the disorder. Because serotonin is critical to fetal brain development, concerns have arisen regarding prenatal exposure to substances that manipulate serotonin levels, such as selective serotonin reuptake inhibitors (SSRIs). This review examines evidence regarding the serotonin system and autism spectrum disorders (ASD), as well as what the literature has reported thus far on developmental effects of prenatal exposure to SSRIs. Possible mechanisms by which SSRIs could affect the fetus during pregcy and clinical implications are also discussed. Though the majority of studies conducted in infants and children suggest prenatal exposure to SSRIs does not affect neurodevelopment, interpretation must be tempered given small sample sizes. The only published study that focused on prenatal SSRI exposure and ASD found an increased risk with exposure to SSRIs, especially during the first trimester. Obstacles that will be faced in future research are isolating medication effects from maternal depression and, given the infrequent occurrence of exposure and outcome, obtaining an adequate sample size. Whether serotonin is an etiologic factor in ASD, and what it points to as a marker for subgrouping, remains unclear. Understanding how the development of ASD might be affected by prenatal factors that influence serotonin levels, such as SSRIs, could identify modifiable targets for prevention. OBJECTIVE: To study the association between parental depression and maternal antidepressant use during pregcy with autism spectrum disorders in offspring. DESIGN: Population based nested case-control study. SETTING: Stockholm County, Sweden, 2001-07. PARTICIPANTS: 4429 cases of autism spectrum disorder (1828 with and 2601 without intellectual disability) and 43,277 age and sex matched controls in the full sample (1679 cases of autism spectrum disorder and 16,845 controls with data on maternal antidepressant use nested within a cohort (n=589,114) of young people aged 0-17 years. MAIN OUTCOME MEASURE: A diagnosis of autism spectrum disorder, with or without intellectual disability. EXPOSURES: Parental depression and other characteristics prospectively recorded in administrative registers before the birth of the child. Maternal antidepressant use, recorded at the first antenatal interview, was available for children born from 1995 onwards. RESULTS: A history of maternal (adjusted odds ratio 1.49, 95% confidence interval 1.08 to 2.08) but not paternal depression was associated with an increased risk of autism spectrum disorders in offspring. In the subsample with available data on drugs, this association was confined to women reporting antidepressant use during pregcy (3.34, 1.50 to 7.47, P=0.003), irrespective of whether selective serotonin reuptake inhibitors (SSRIs) or non-selective monoamine reuptake inhibitors were reported. All associations were higher in cases of autism without intellectual disability, there being no evidence of an increased risk of autism with intellectual disability. Assuming an unconfounded, causal association, antidepressant use during pregcy explained 0.6% of the cases of autism spectrum disorder. CONCLUSIONS: In utero exposure to both SSRIs and non-selective monoamine reuptake inhibitors (tricyclic antidepressants) was associated with an increased risk of autism spectrum disorders, particularly without intellectual disability. Whether this association is causal or reflects the risk of autism with severe depression during pregcy requires further research. However, assuming causality, antidepressant use during pregcy is unlikely to have contributed significantly towards the dramatic increase in observed prevalence of autism spectrum disorders as it explained less than 1% of cases. RATIONALE: Women are increasingly prescribed selective serotonin reuptake inhibitors (SSRIs) during pregcy, with potential implications for neurodevelopment. Whether prenatal SSRI exposure has an effect on neurodevelopment and behavior in the offspring is an important area of investigation. OBJECTIVES: The aim of this paper was to review the existing preclinical and clinical literature of prenatal SSRI exposure on serotonin-related behaviors and markers in the offspring. The goal is to determine if there is a signal in the literature that could guide clinical care and/or inform research. RESULTS: Preclinical studies (n = 4) showed SSRI exposure during development enhanced depression-like behavior. Half of rodent studies examining anxiety-like behavior (n = 13) noted adverse effects with SSRI exposure. A majority of studies of social behavior (n = 4) noted a decrease in sociability in SSRI exposed offspring. Human studies (n = 4) examining anxiety in the offspring showed no adverse effects of prenatal SSRI exposure. The outcome of one study suggested that children with autism were more likely to have a mother who was prescribed an SSRI during pregcy. CONCLUSIONS: Preclinical findings in rodents exposed to SSRIs during development point to an increase in depression- and anxiety-like behavior and alteration in social behaviors in the offspring, though both the methods used and the findings were not uniform. These data are not robust enough to discourage use of SSRIs during human pregcy, particularly given the known adverse effects of maternal mental illness on pregcy outcomes and infant neurodevelopment. Future research should focus on consistent animal models and prospective human studies with larger samples. Autism spectrum disorders (ASD) are currently diagnosed in the presence of impairments in social interaction and communication, and a restricted range of activities and interests. However, there is considerable variability in the behaviors of different individuals with an ASD diagnosis. The heterogeneity spans the entire range of IQ and language abilities, as well as other behavioral, communicative, and social functions. While any psychiatric condition is likely to incorporate a degree of heterogeneity, the variability in the nature and severity of behaviors observed in ASD is thought to exceed that of other disorders. The current paper aims to provide a model for future research into ASD subgroups. In doing so, we examined whether two proposed risk factors - low birth weight (LBW), and in utero exposure to selective serotonin reuptake inhibitors (SSRIs) - are associated with greater behavioral homogeneity. Using data from the Western Australian Autism Biological Registry, this study found that LBW and maternal SSRI use during pregcy were associated with greater sleep disturbances and a greater number of gastrointestinal complaints in children with ASD, respectively. The findings from this "proof of principle" paper provide support for this "bottom-up" approach as a feasible method for creating homogenous groups.

Which transcription factors are involved in E-cadherin repression during EMT?

Downregulation of E-cadherin is a crucial event for epithelial to mesenchymal transition (EMT) in embryonic development and cancer progression. Overexpression of Snail1 (Snail), Snail2 (Slug), Zeb1, Twist, SIP1 and DeltaEF1 have been found to mediate E-cadherin repression, induce the mesenchymal markers vimentin and fibronectin, and finally promote the migratory and invasive capabilities in cancer cells.

Downregulation of E-cadherin is a crucial event for epithelial to mesenchymal transition (EMT) in embryonic development and cancer progression. Using the EpFosER mammary tumour model we show that during EMT, upregulation of the transcriptional regulator deltaEF1 coincided with transcriptional repression of E-cadherin. Ectopic expression of deltaEF1 in epithelial cells was sufficient to downregulate E-cadherin and to induce EMT. Analysis of E-cadherin promoter activity and chromatin immunoprecipitation identified deltaEF1 as direct transcriptional repressor of E-cadherin. In human cancer cells, transcript levels of deltaEF1 correlated directly with the extent of E-cadherin repression and loss of the epithelial phenotype. The protein was enriched in nuclei of human cancer cells and physically associated with the E-cadherin promoter. RNA interference-mediated downregulation of deltaEF1 in cancer cells was sufficient to derepress E-cadherin expression and restore cell to cell adhesion, suggesting that deltaEF1 is a key player in late stage carcinogenesis. Epithelial-mesenchymal transition (EMT), a crucial event in cancer progression and embryonic development, is induced by transforming growth factor (TGF)-beta in mouse mammary NMuMG epithelial cells. Id proteins have previously been reported to inhibit major features of TGF-beta-induced EMT. In this study, we show that expression of the deltaEF1 family proteins, deltaEF1 (ZEB1) and SIP1, is gradually increased by TGF-beta with expression profiles reciprocal to that of E-cadherin. SIP1 and deltaEF1 each dramatically down-regulated the transcription of E-cadherin in NMuMG cells through direct binding to the E-cadherin promoter. Silencing of the expression of both SIP1 and deltaEF1, but not either alone, completely abolished TGF-beta-induced E-cadherin repression. However, expression of mesenchymal markers, including fibronectin, N-cadherin, and vimentin, was not affected by knockdown of SIP1 and deltaEF1. TGF-beta-induced the expression of Ets1, which in turn activated deltaEF1 promoter activity. Moreover, up-regulation of SIP1 and deltaEF1 expression by TGF-beta was suppressed by knockdown of Ets1 expression. In addition, Id2 suppressed the TGF-beta- and Ets1-induced up-regulation of deltaEF1. Taken together, these findings suggest that the deltaEF1 family proteins, SIP1 and deltaEF1, are necessary, but not sufficient, for TGF-beta-induced EMT and that Ets1 induced by TGF-beta may function as an upstream transcriptional regulator of SIP1 and deltaEF1. AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metaplasia and esophageal adenocarcinoma specimens was examined by real-time reverse transcription-polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. The effect of Slug on epithelial mesenchymal transition (EMT) markers was examined by transfection of Slug into an adenocarcinoma line OE33. RESULTS: Cellular localisation of Slug in Barrett's metaplasia was largely cytoplasmic whilst in adenocarcinoma it was nuclear. Semi-quantitative analysis indicated that Slug was more abundant in adenocarcinoma compared to matched Barrett's metaplastic specimens. Snail and Twist were expressed in adenocarcinoma but were cytoplasmic in location and not induced compared to Barrett's mucosa. These observations were supported by mRNA studies where only Slug mRNA was shown to be over-expressed in adenocarcinoma and inversely correlated to E-cadherin expression. Overexpression of Slug in OE33 mediated E-cadherin repression and induced the mesenchymal markers vimentin and fibronectin. CONCLUSION: Progression to adenocarcinoma is associated with increased Slug expression and this may represent a mechanism of E-cadherin silencing. Functional loss of the cell-cell adhesion molecule E-cadherin is an essential event for epithelial-mesenchymal transition (EMT), a process that allows cell migration during embryonic development and tumour invasion. In most carcinomas, transcriptional repression has emerged as the main mechanism responsible for E-cadherin downregulation. Here, we report the identification of class I bHLH factor E2-2 (TCF4/ITF2) as a new EMT regulator. Both isoforms of E2-2 (E2-2A and E2-2B) induce a full EMT when overexpressed in MDCK cells but without affecting the tumorigenic properties of parental cells, in contrast to other EMT inducers, such as Snail1 or class I bHLH E47. E-cadherin repression mediated by E2-2 is indirect and independent of proximal E-boxes of the promoter. Knockdown studies indicate that E2-2 expression is dispensable for maintece of the EMT driven by Snail1 and E47. Comparative gene-profiling analysis reveals that E2-2 factors induce similar, yet distinct, genetic programs to that induced by E47 in MDCK cells. These results, together with the embryonic expression pattern of Tcf4 and E2A (which encodes E12/E47), support a distinct role for E2-2 and suggest an interesting interplay between E-cadherin repressors in the regulation of physiological and pathological EMT processes. Breast tumor interleukin-6 (IL-6) levels increase with tumor grade, and elevated serum IL-6 correlates with poor breast cancer patient survival. Epithelial-mesenchymal transition (EMT) phenotypes such as impaired E-cadherin expression or aberrant Vimentin induction are associated with enhanced metastasis and unfavorable clinical outcome in breast cancer. Despite this fact, few tumor microenvironment-derived extracellular signaling factors capable of provoking such a phenotypic transition have been identified. In this study, we showed that IL-6 promoted E-cadherin repression among a panel of estrogen receptor-alpha-positive human breast cancer cells. Furthermore, ectopic stable IL-6 expressing MCF-7 breast adenocarcinoma cells (MCF-7(IL-6)) exhibited an EMT phenotype characterized by impaired E-cadherin expression and induction of Vimentin, N-cadherin, Snail and Twist. MCF-7(IL-6) cells formed xenograft tumors that displayed loss of E-cadherin, robust Vimentin induction, increased proliferative indices, advanced tumor grade and undifferentiated histology. Finally, we showed aberrant IL-6 production and STAT3 activation in MCF-7 cells that constitutively express Twist, a metastatic regulator and direct transcriptional repressor of E-cadherin. To our knowledge, this is the first study that shows IL-6 as an inducer of an EMT phenotype in breast cancer cells and implicates its potential to promote breast cancer metastasis. What's known on the subject? and What does the study add? Epithelial-mesenchymal transition (EMT) is involved in tumor progression where the underlying cellular changes associated with EMT have been identified in in vitro models and confirmed in a limited number of in vivo studies. ZEB1, which targets E-cadherin repression, is a transcriptional regulator that has been implicated in EMT, and is associated with uterine and colorectal cancers. Regulation of ZEB1 expression has been shown to involve different microRNAs (miRNAs), identifying a potential role for miRNA in EMT. In the present study we have identified novel expression of ZEB1 in bladder tumours and shown a role for ZEB1 in enhanced migration and invasion potential in in vitro assays. Confirmation of ZEB1 expression in bladder tumours was shown in tissue microarrays (TMAs). OBJECTIVE: To evaluate ZEB1 expression in bladder tumorigenesis and define a possible role for this transcription factor in urothelial carcinomas of the bladder (UCBs). MATERIALS AND METHODS: Five hundred and fifty-eight samples were assembled in 10 tissue microarrays (TMAs; 263 non-muscle-invasive Ta/T1/Tis, 295 muscle-invasive T2-T4). All tumours were transitional cell carcinomas (TCCs) and processed for immunohistochemistry to assess nuclear ZEB1 expression. Expression levels of ZEB1 were modulated in bladder carcinoma cell lines CUBIII or UM-UC-3 after forced expression or shRNA knockdown, respectively. Protein expression levels were determined using western blot analysis and transfectants were assessed for migration and invasion potential in standard in vitro assays. RESULTS: Nuclear ZEB1 expression was recorded in 22.8% of non-muscle-invasive UCBs and 21.7% of muscle-invasive UCBs, including 24.1% grade I/II and 21.1% grade III tumours, and absent in normal bladder mucosa. No significant correlation was observed for tumour stage and grade, nodal involvement, vascular invasion, metastasis and overall or cancer-specific survival. The introduction or knockdown of ZEB1 expression in bladder carcinoma cell lines showed enhanced or reduced migration and invasive potential, respectively. Changes in ZEB1 expression were accompanied by altered microRNA (miRNA) expression underlying events linked to epithelial-mesenchymal transition (EMT). CONCLUSION: The results in the present study showed novel expression of ZEB1 in bladder cancer in the absence of a link to clinical variables of change, including metastasis and survival. However, in vitro assays showed enhanced or reduced migration and invasion after the introduction or reduction of ZEB1, respectively, in transfected bladder cell lines. Modulation in expression of ZEB1 was closely linked to changes in the miR-200 family along with alternative known prognostic indicators of bladder tumour progression. Expression of E-cadherin, a hallmark of epithelial-mesenchymal transition (EMT), is often lost due to promoter DNA methylation in basal-like breast cancer (BLBC), which contributes to the metastatic advantage of this disease; however, the underlying mechanism remains unclear. Here, we identified that Snail interacted with Suv39H1 (suppressor of variegation 3-9 homolog 1), a major methyltransferase responsible for H3K9me3 that intimately links to DNA methylation. We demonstrated that the SNAG domain of Snail and the SET domain of Suv39H1 were required for their mutual interactions. We found that H3K9me3 and DNA methylation on the E-cadherin promoter were higher in BLBC cell lines. We showed that Snail interacted with Suv39H1 and recruited it to the E-cadherin promoter for transcriptional repression. Knockdown of Suv39H1 restored E-cadherin expression by blocking H3K9me3 and DNA methylation and resulted in the inhibition of cell migration, invasion and metastasis of BLBC. Our study not only reveals a critical mechanism underlying the epigenetic regulation of EMT, but also paves a way for the development of new treatment strategies against this disease. Snail family proteins regulate transcription of molecules for cell-cell adhesion during epithelial-mesenchymal transition (EMT). Based on putative glycogen synthase kinase 3β (GSK-3β) phosphorylation sites within the Slug/Snail2, we explored the significance of GSK-3β-mediated phosphorylation in Slug/Snail2 expression during EMT. Mutation of the putative GSK-3β phosphorylation sites (S92/96A or S100/104A) enhanced the Slug/Snail2-mediated EMT properties of E-cadherin repression and vimentin induction, compared with wild-type Slug/Snail2. S92/96A mutation inhibited degradation of Slug/Snail2 and S100/104A mutation extended nuclear stabilization. Inhibition of GSK-3β activity caused similar effects, as did the phosphorylation mutations. Thus, our study suggests that GSK-3β-mediated phosphorylation of Slug/Snail2 controls its turnover and localization during EMT. The proliferation, directional migration to the vitreous and epithelial-mesenchymal transition (EMT) of quiescent, differentiated retinal pigment epithelium (RPE) cells is a major feature in the development of proliferative vitreoretinopathy (PVR) following exposure of the immuno-privileged eye niche to serum components, thrombin among them. We have previously documented thrombin induction of RPE cell proliferation and migration. We here analyzed the effect of thrombin on the E/N cadherin switch, a hallmark of EMT. Results show that thrombin induces the specific repression of epithelial E-cadherin gene transcription, alongside with the up-regulation of mesenchymal N-cadherin protein in RPE cells. We demonstrate, for the first time, that thrombin induces E-cadherin repression by stimulating snail-2 (SLUG) transcription factor expression, and the concomitant up-regulation of N-cadherin through the transcription-independent increase in protein translation promoted by PI3K/PKC-ζ/mTOR signaling. Our present findings suggest that the activation of protease-activated receptor-1 (PAR-1) by thrombin induces EMT of RPE cells, further supporting a central role for thrombin in PVR pathogenesis. Snail1 (Snail) and Snail2 (Slug) are transcription factors that share a similar DNA binding structure of four and five C2H2 zinc finger motifs (ZF), respectively. Both factors bind specifically to a subset of E-box motifs (E2-box: CAGGTG/CACCTG) in target promoters like the E-cadherin promoter and are key mediators of epithelial-to-mesenchymal transition (EMT). However, there are differences in the biological actions, in binding affinities to E-cadherin promoter, and in the target genes of Snail1 and Snail2, although the molecular bases are presently unknown. In particular, the role of each Snail1 and Snail2 ZF in the binding to E-boxes and in EMT induction has not been previously explored. We have approached this question by modeling Snail1 and Snail2 protein-DNA interactions and through mutational and functional assays of different ZFs. Results show that Snail1 efficient repression and binding to human and mouse E-cadherin promoter as well as EMT-inducing ability require intact ZF1 and ZF2, while for Snail2, either ZF3 or ZF4 is essential for those functions. Furthermore, the differential distribution of E2-boxes in mouse and human E-cadherin promoters also contributes to the differential Snail factor activity. These data indicate a non-equivalent role of Snail1 and Snail2 ZFs in gene repression, contributing to the elucidation of the molecular differences between these important EMT regulators.

Is desmin an intermediate filament protein involved in Dilated Cardiomyopathy (DCM)?

According to the predominant view, desmin mutations cause dilated cardiomyopathy (DCM). Mice deficient in desmin, the muscle-specific member of the intermediate filament gene family, display defects in all muscle types and particularly in the myocardium. Desmin null hearts develop cardiomyocyte hypertrophy and dilated cardiomyopathy (DCM) characterized by extensive myocyte cell death, calcific fibrosis and multiple ultrastructural defects. Desmin defects were also recently identified in 1 familial dilated cardiomyopathy.

The cardiac cytoskeleton and the extracellular matrix play an essential role for maintaining cellular integrity and function of the myocardium. The network of microtubules and intermediate filaments are disrupted by the inflammatory reaction which depends on resident cells (myocytes, fibroblasts, endothel cells) and on systemic cells (granulocytes, macrophages, monocytes, lymphocytes). Changes in the cardiac cytoskeleton and the extracellular matrix may affect contractile function, since the cytoskeleton organizes the intra- and intercellular architecture. The inflammation in heart disease and the induction of fibrosis are mediated by cytokines and growth factors derived from fibroblast activation and from the B- and T-cell activity. A possible connecting link for the induction of fibrosis is the presentation of the myocardial antigens to the immune system and its subsequent cellular and humoral autoreactive response (Figure 1). Different autoantibodies to sarcolemmal and myolemmal antigens, to laminin, to extracellular matrix proteins, to the collagens and to myofibrils were demonstrated both in endomyocardial biopsy and as circulating autoantibodies in the peripheral blood. The pathophysiological role of the cytoskeleton and the extracellular matrix are well defined for beta-tubulin, fibronectin, laminin, desmin, vimentin, vinculin and collagen: beta-tubulin is increased or altered in dilated cardiomyopathy (DCM). Fibronectin appears in irregular forms in DCM as well. Ultrastructural analysis showed an increased content of laminin in basement membranes. In addition anti-laminin antibodies were found in 73% of patients with myocarditis and in 78% of patients with DCM. Desmin (z-bands) are partly destroyed in DCM. Anti-desmin antibody titers as indicators of a possible secondary immune response are found high in patients with acute myocarditis declining during reconvalescence and are also elevated in DCM. The vimentin of the endothelial cells and the vinculin of the sarcolemmal membrane and the intercalated discs have been demonstrated to be irregularly shaped and increased in content in DCM whereas in myocarditis their appearance and content is still unknown. The intracellular content of collagen type 5 is increased in DCM and in myocarditis. The presence of autoantibodies to components of the cytoskeleton and the extracellular matrix in myocarditis and perimyocarditis is well-described. Antibodies to the myolemma and the sarcolemma are found in almost all patients with perimyocarditis in the serum or bound in the biopsy. Some of them have been known cytolytic in vitro to isolated heart cells. In pericarditis a shift to antibodies to the extracellular matrix, collagen and intermediate filaments is observed among the circulating antibodies.(ABSTRACT TRUNCATED AT 400 WORDS) Familial dilated cardiomyopathy (DCM) should be an "evidence-based" diagnosis derived from clinical and echocardiographic screening of informed and consenting relatives of index patients, and on the examination of clinical reports for deceased relatives. Most familial dilated cardiomyopathy pedigrees show an autosomal pattern of inheritance. Very few of them are X-linked and matrilinear. Autosomal recessive inheritance is difficult to be assessed in an evidence-based setting. By linkage analysis, several loci, but no disease gene, have been identified. At present, few cases of familial dilated cardiomyopathy can benefit of a molecular diagnosis. The diagnosis of dystrophin defect-related dilated cardiomyopathy is important for patients and families, especially for carrier detection. These patients present X-linked inheritance, domit cardiac involvement and raised levels of serum creatine phosphokinase. Defects of the glycoprotein complex associated to dystrophin (DAG) are rare skeletal muscle diseases with possible cardiac involvement. Mitochondrial diseases, both pure cardiomyopathies and multiorgan syndromes involving the heart, are associated to defects of mitochondrial DNA genes or of nuclear genes coding for mitochondrial proteins. Barth's syndrome develops in male children with granulocytopenia, dilated cardiomyopathy, and methylglutaconic aciduria. Cardiomyopathies with atrioventricular block are observed in hemochromatosis, Emery-Dreifuss syndrome, desmin storage disease, and in isolated familial dilated cardiomyopathy. Actin defects were recently identified in 2 unrelated patients with familial dilated cardiomyopathy. Desmin defects were also recently identified in 1 familial dilated cardiomyopathy. The overall knowledge, although in progression, is still limited. Clinical family screening identifies familial forms, preclinical cases, and inheritance pattern. By candidate gene screening, the molecular diagnosis can be provided for dystrophin, DAG, mitochondrial DNA, actin and desmin gene defects. Mice deficient in desmin, the muscle-specific member of the intermediate filament gene family, display defects in all muscle types and particularly in the myocardium. Desmin null hearts develop cardiomyocyte hypertrophy and dilated cardiomyopathy (DCM) characterized by extensive myocyte cell death, calcific fibrosis and multiple ultrastructural defects. Several lines of evidence suggest impaired vascular function in desmin null animals. To determine whether altered capillary function or an intrinsic cardiomyocyte defect is responsible for desmin null DCM, transgenic mice were generated to rescue desmin expression specifically to cardiomyocytes. Desmin rescue mice display a wild-type cardiac phenotype with no fibrosis or calcification in the myocardium and normalization of coronary flow. Cardiomyocyte ultrastructure is also restored to normal. Markers of hypertrophy upregulated in desmin null hearts return to wild-type levels in desmin rescue mice. Working hearts were perfused to assess coronary flow and cardiac power. Restoration of a wild-type cardiac phenotype in a desmin null background by expression of desmin specifically within cardiomyocyte indicates that defects in the desmin null heart are due to an intrinsic cardiomyocytes defect rather than compromised coronary circulation. Canine-dilated cardiomyopathy (DCM) in dogs is a disease of the myocardium associated with dilatation and impaired contraction of the ventricles and is suspected to have a genetic cause. A missense mutation in the desmin gene (DES) causes DCM in a human family. Human DCM closely resembles the canine disease. In the present study, we evaluated whether DES gene mutations are responsible for DCM in Dobermann dogs. We have isolated bacterial artificial chromosome clones (BACs) containing the canine DES gene and determined the chromosomal location by fluorescence in situ hybridization (FISH). Using data deposited in the NCBI trace archive and GenBank, the canine DES gene DNA sequence was assembled and seven single nucleotide polymorphisms (SNPs) were identified. From the canine DES gene BAC clones, a polymorphic microsatellite marker was isolated. The microsatellite marker and four informative desmin SNPs were typed in a Dobermann family with frequent DCM occurrence, but the disease phenotype did not associate with a desmin haplotype. We concluded that mutations in the DES gene do not play a role in Dobermann DCM. Availability of the microsatellite marker, SNPs and DNA sequence reported in this study enable fast evaluation of the DES gene as a DCM candidate gene in other dog breeds with DCM occurrence. BACKGROUND: Desmin-related myofibrillar myopathy (DRM) is a cardiac and skeletal muscle disease caused by mutations in the desmin (DES) gene. Mutations in the central 2B domain of DES cause skeletal muscle disease that typically precedes cardiac involvement. However, the prevalence of DES mutations in dilated cardiomyopathy (DCM) without skeletal muscle disease is not known. METHODS AND RESULTS: Denaturing high-performance liquid chromatography was used to screen DES for mutations in 116 DCM families from the Familial Dilated Cardiomyopathy Registry and in 309 subjects with DCM from the Beta-Blocker Evaluation of Survival Trial (BEST). DES mutations were transfected into SW13 and human smooth muscle cells and neonatal rat cardiac myocytes, and the effects on cytoskeletal desmin network architecture were analyzed with confocal microscopy. Five novel missense DES mutations, including the first localized to the highly conserved 1A domain, were detected in 6 subjects (1.4%). Transfection of DES mutations in the 2B domain severely disrupted the fine intracytoplasmic staining of desmin, causing clumping of the desmin protein. A tail domain mutation (Val459Ile) showed milder effects on desmin cytoplasmic network formation and appears to be a low-penetrant mutation restricted to black subjects. CONCLUSIONS: The prevalence of DES mutations in DCM is between 1% and 2%, and mutations in the 1A helical domain, as well as the 2B rod domain, are capable of causing a DCM phenotype. The lack of severe disruption of cytoskeletal desmin network formation seen with mutations in the 1A and tail domains suggests that dysfunction of seemingly intact desmin networks is sufficient to cause DCM. AIMS: Desmin, the muscle-specific intermediate filament protein, is a major target in dilated cardiomyopathy and heart failure in humans and mice. The hallmarks of desmin-deficient (des(-/-)) mice pathology include pronounced myocardial degeneration, extended fibrosis, and osteopontin (OPN) overexpression. We sought to identify the molecular and cellular events regulating adverse cardiac remodelling in des(-/-) mice and their potential link to OPN. METHODS AND RESULTS: In situ hybridization, histology, and immunostaining demonstrated that inflammatory cells and not cardiomyocytes were the source of OPN. RNA profile comparison revealed that activation of inflammatory pathways, sustained by innate immunity mechanisms, predominated among all changes occurring in degenerating des(-/-) myocardium. The expression of the most highly up-regulated genes (OPN: 226×, galectin-3: 26×, osteoactivin/Gpnmb/DC-HIL: 160× and metalloprotease-12: 98×) was associated with heart infiltrating macrophages. To evaluate the role of OPN, we generated des(-/-)OPN(-/-) mice and compared their cardiac function and remodelling indices with those of des(-/-). Osteopontin promoted cardiac dysfunction in this model since des(-/-)OPN(-/-) mice showed 53% improvement of left ventricular function, paralleled to an up to 44% reduction in fibrosis. The diminished fibrotic response in the absence of OPN could be partly mediated by a dramatic reduction in myocardial galectin-3 levels, associated with an impaired galectin-3 secretion by OPN-deficient infiltrating macrophages. CONCLUSION: Cardiomyocyte death due to desmin deficiency leads to inflammation and subsequent overexpression of a series of remodelling modulators. Among them, OPN seems to be a major regulator of des(-/-) adverse myocardial remodelling and it functions at least by potentiating galectin-3 up-regulation and secretion.

Is lambrolizumab effective for treatment of patients with melanoma ?

Lambrolizumab, a programmed death-1 receptor (PD-1)/its ligand (PD-L1) antibody, has been shown to be effective for treatment of patients with melanoma. High rate of sustained tumor regression with mainly minimal adverse effects in melanoma patients treated with lambrolizumab has been reported. Because of all these reasons PD-1/PD-L1 antibodies are considered 'drug of the year.

BACKGROUND: The programmed death 1 (PD-1) receptor is a negative regulator of T-cell effector mechanisms that limits immune responses against cancer. We tested the anti-PD-1 antibody lambrolizumab (previously known as MK-3475) in patients with advanced melanoma. METHODS: We administered lambrolizumab intravenously at a dose of 10 mg per kilogram of body weight every 2 or 3 weeks or 2 mg per kilogram every 3 weeks in patients with advanced melanoma, both those who had received prior treatment with the immune checkpoint inhibitor ipilimumab and those who had not. Tumor responses were assessed every 12 weeks. RESULTS: A total of 135 patients with advanced melanoma were treated. Common adverse events attributed to treatment were fatigue, rash, pruritus, and diarrhea; most of the adverse events were low grade. The confirmed response rate across all dose cohorts, evaluated by central radiologic review according to the Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, was 38% (95% confidence interval [CI], 25 to 44), with the highest confirmed response rate observed in the cohort that received 10 mg per kilogram every 2 weeks (52%; 95% CI, 38 to 66). The response rate did not differ significantly between patients who had received prior ipilimumab treatment and those who had not (confirmed response rate, 38% [95% CI, 23 to 55] and 37% [95% CI, 26 to 49], respectively). Responses were durable in the majority of patients (median follow-up, 11 months among patients who had a response); 81% of the patients who had a response (42 of 52) were still receiving treatment at the time of analysis in March 2013. The overall median progression-free survival among the 135 patients was longer than 7 months. CONCLUSIONS: In patients with advanced melanoma, including those who had had disease progression while they had been receiving ipilimumab, treatment with lambrolizumab resulted in a high rate of sustained tumor regression, with mainly grade 1 or 2 toxic effects. (Funded by Merck Sharp and Dohme; ClinicalTrials.gov number, NCT01295827.). Programmed death-1 receptor (PD-1)/its ligand (PD-L1) antibodies have changed the landscape in oncology in 2013. The most mature results have been obtained in advanced melanoma patients. They indicate important response rates and high quality responses or prolonged duration. Also in renal cancer and in lung cancer remarkable activity has been demonstrated. Thus it is clear that these antibodies have a very broad potential and trials in many tumour types are being initiated. Breaking tolerance at the tumour site is a potent phenomenon and the potential for synergy with other checkpoint inhibitors such as ipilimumab have also been demonstrated in 2013. Long term tumour control now seems achievable and thus the concept of a clinical cure is emerging by modulation of the immune system. These antibodies bring immunotherapy to the forefront and indicate that immune-modulation will be a key component of therapeutic strategies from now on. Because of all these reasons PD-1/PD-L1 antibodies are considered 'drug of the year'. Until recently there was no effective systemic therapy for metastatic melanoma. Increased understanding of tumor biology and immune regulation has led to the development of drugs targeting the mitogen-activated protein kinase (MAPK) pathway (BRAF inhibitors and MEK inhibitors) and T-cell regulation (CTLA4 antibodies). These drugs are the new standard of care, however barriers to better patient outcomes include limited responses and significant toxicities (CTLA4 antibodies) and lack of durability in the majority of cases (BRAF and MEK inhibitors). This review discusses the next stages of development of treatments in melanoma, including immune checkpoint blocking drugs targeting the PD-1/PD-L1 axis, and the use of BRAF and MEK inhibitors in combination. Both approaches lead to a higher proportion of durable responses coupled with less toxicity. In an effort to improve outcomes even further, clinical trials of combinations of MAPK inhibitors, immunotherapies and other signal pathway inhibitors are underway. Adjuvant studies of many of these drugs have commenced, with the hope of also improving outcomes in patients with early-stage melanoma. Metastatic melanoma remained for decades without any effective treatment and was thus considered as a paradigm of cancer resistance. Recent progress with understanding of the molecular mechanisms underlying melanoma initiation and progression revealed that melanomas are genetically and phenotypically heterogeneous tumors. This recent progress has allowed for the development of treatment able to improve for the first time the overall disease-free survival of metastatic melanoma patients. However, clinical responses are still either too transient or limited to restricted patient subsets. The complete cure of metastatic melanoma therefore remains a challenge in the clinic. This review aims to present the recent knowledge and discoveries of the molecular mechanisms involved in melanoma pathogenesis and their exploitation into clinic that have recently facilitated bench to bedside advances. Melanoma has the highest mortality of all the skin cancer subtypes. Historically, chemotherapy and immunologic therapies have yielded only modest results in the treatment of metastatic melanoma. The discovery of prevalent V600 BRAF mutations driving proliferation makes this oncogenic protein an ideal target for therapy. Dabrafenib, a reversible inhibitor of mutant BRAF kinase, improved response rates and median progression-free survival in patients with V600E BRAF-mutant metastatic melanoma, including those with brain metastases. With a well-tolerated toxicity profile, dabrafenib is effective as a monotherapy; however, resistance eventually develops in almost all patients. As a result, current research is exploring the role of combination therapies with dabrafenib to overcome resistance.

List human diseases involving genomic imprinting.

Prader Willi Syndrome Angelman syndrome Beckwith-Wiedemann syndrome Hydatidiform mole Cancer Silver-Russell syndrome Diabetes

The phenomenon of parental imprinting has become increasingly important in disciplines such as evolution, genetics, molecular biology, embryology and pathology. Principally, parental imprinting refers to a parent-of-origin dependent expression of a subset of autosomal loci, independent of the sex of the offspring. Today, at least seven such loci have been identified, including the human IGF2 gene. It appears that the set of imprinted genes is not always identical between the species, although the importance of maintaining this kind of gene regulation is evolutionarily conserved. It is particularly interesting from the clinical point of view that a number of human diseases, such as the Beckwith-Wiedemann and Prader-Willi/Angelman syndromes, appear to involve unbalanced parental contributions of imprinted loci. We show here that the four different human IGF2 promoters are expressed mono- and/or biallelically in complex patterns in postnatal liver specimens. Parental genomic imprinting is the phenomenon in which the behavior of a gene is modified, depending on the sex of the transmitting parent [Peterson and Sapienza (1993): Annu Rev Genet 27:7-31]. Recent observations have revealed that the inheritance patterns, age-of-onset, severity, and etiology of certain human diseases can be explained by aberrations in the establishment or the maintece of the imprint. Examples include the Prader-Willi, Angelman, and Beckwith-Wiedemann syndromes [Nicholls (1994): Am J Hum Genet 54:733-740], maligcy [Sapienza (1990): Biochim Biophys Acta 1072:51-61; Feinberg (1993): Nat Genet 4:110-113], and insulin-dependent diabetes mellitus (IDDM) [Julier et al. (1994) Nature 354:155-159; Bennett et al. (1995) Nat Genet 9:284-292]. We review the evidence that implicates an imprinted gene in the INS-IGF2 region of chromosome 11p15 in the etiology of IDDM (referred to as the IDDM2 locus) and show that in human fetal pancreas, INS is not imprinted, thus providing an argument against INS as the candidate gene. We also examine imprinting effects on the expression of IGF2 in components of the human immune system believed to be important in IDDM and show imprinted expression in fetal thymus as early as 15 weeks gestation. We demonstrate further that in the circulating mononuclear cells of two individuals, lectin-stimulated IGF2 transcription was biallelic, indicating relaxation of imprinting, whereas in one individual, transcription was monoallelic. Finally, we review the current available data supporting a role for insulin-like growth factor-II (IGF-II) in the immune system and, more specifically, discuss the evidence supporting a role for the IGFs in the prevention of apoptosis. These data have led us to formulate a novel hypothesis that could mechanistically explain the involvement of the IDDM2 locus in the pathogenesis of IDDM. Changes in DNA methylation profiles are common features of development and in a number of human diseases, such as cancer and imprinting disorders like Beckwith-Wiedemann and Prader-Willi/Angelman syndromes. This suggests that DNA methylation is required for proper gene regulation during development and in differentiated tissues and has clinical relevance. DNA methylation is also involved in X-chromosome inactivation and the allele-specific silencing of imprinted genes. This review describes possible mechanisms by which DNA methylation can regulate gene expression, using imprinted genes as examples. The molecular basis of methylation-mediated gene regulation is related to changes in chromatin structure and appears to be similar for both imprinted and biallelically expressed genes. Deregulation of imprinted genes has been observed in a number of human diseases such as Beckwith-Wiedemann syndrome, Prader-Willi/Angelman syndromes and cancer. Imprinting diseases are characterised by complex patterns of mutations and associated phenotypes affecting pre- and postnatal growth and neurological functions. Regulation of imprinted gene expression is mediated by allele-specific epigenetic modifications of DNA and chromatin. These modifications preferentially affect central regulatory elements that control in cis over long distances allele-specific expression of several neighbouring genes. Investigations of imprinting diseases have a strong impact on biomedical research and provide interesting models for function and mechanisms of epigenetic gene control. Genomic imprinting is a mechanism by which only one copy of a gene pair is expressed, and this expression is determined by the parental origin of the copy. The deregulation of imprinted genes has been implicated in a number of human diseases. The Imprinted Gene Catalogue now has more than 200 genes listed, and estimates based on mouse models suggest many more may exist in humans. Therefore, the development of methods to identify such genes is important. In this communication, we present a parametric model-based approach to analyzing arbitrary-sized pedigree data for genomic imprinting. We have modified widely used LINKAGE program to incorporate our proposed approach. In addition, our approach allows for the use of sex-specific recombinations in the analysis, which is of particular importance in a genome-wide analysis for imprinted genes. We compared our imprinting analysis approach to that implemented in the GENEHUNTER-IMPRINT program using simulation studies as well as by analyzing causal genes in Angelman's syndrome families, which are known to be imprinted. These analyses showed that the proposed approach is very powerful for detecting imprinted genes in large pedigrees. Genomic imprinting is an epigenetic form of regulation of gene expression. Imprinted genes are transcribed from one allele of specific parental origin. Such genes are normally involved in embryonic growth and behavioral development. Deregulation of imprinted genes has been observed in a number of human diseases as gestation trophoblastic disease, Prader-Willi, Angelmann and Beckwith-Wiedemann syndromes and plays significant role in the carcinogenesis. Review of recent knowledge on mechanism and regulation of imprinting is presented in this paper. Imprinted genes play important roles in the regulation of growth and development, and several have been shown to influence behavior. Their allele-specific expression depends on inheritance from either the mother or the father, and is regulated by "imprinting control regions" (ICRs). ICRs are controlled by DNA methylation, which is present on one of the two parental alleles only. These allelic methylation marks are established in either the female or the male germline, following the erasure of preexisting DNA methylation in the primordial germ cells. After fertilization, the allelic DNA methylation at ICRs is maintained in all somatic cells of the developing embryo. This epigenetic "life cycle" of imprinting (germline erasure, germline establishment, and somatic maintece) can be disrupted in several human diseases, including Beckwith-Wiedemann syndrome (BWS), Prader-Willi syndrome (PWS), Angelman syndrome and Hydatidiform mole. In the neurodevelopmental Rett syndrome, the way the ICR mediates imprinted expression is perturbed. Recent studies indicate that assisted reproduction technologies (ART) can sometimes affect the epigenetic cycle of imprinting as well, and that this gives rise to imprinting disease syndromes. This finding warrants careful monitoring of the epigenetic effects, and absolute risks, of currently used and novel reproduction technologies. Oxidative stress (OS) is involved in several human diseases, including obesity, diabetes, atherosclerosis, carcinogenesis, as well as genetic diseases. We previously found that OS occurs in Down Syndrome as well as in Beckwith-Wiedemann Syndrome (BWS). Here we describe the clinical case of a female patient with Prader Willi Syndrome (PWS), a genomic imprinting disorder, characterized by obesity, atherosclerosis and diabetes mellitus type 2, pathologies in which a continuous and important production of free radicals takes place. We verified the presence of OS by measuring a redox biomarkers profile including total hydroperoxides (TH), non protein-bound iron (NPBI), thiols (SH), advanced oxidation protein products (AOPP) and isoprostanes (IPs). Thus we introduced in therapy an antioxidant agent, namely potassium ascorbate with ribose (PAR), in addition to GH therapy and we monitored the redox biomarkers profile for four years. A progressive decrease in OS biomarkers occurred until their normalization. In the meantime a weight loss was observed together with a steady growth in standards for age and sex.

Why are insulators necessary in gene therapy vectors?

a) They inhibit oncogene activation upon vector integration and b) They maximize the probability of vector expression upon integration in heterochromatinic regions

Low efficiency of gene transfer is the main obstacle for a clinically effective gene therapy at the level of the pluripotent hematopoietic stem cell. Another important aspect of stem cell gene therapy, the actual expression of the transduced genes, has only been investigated adequately in very few studies, mainly for globin genes. Transcriptional silencing and position effects due to negative effects of surrounding chromatin on the expression of randomly integrated vector sequences may seriously jeopardize the success of current gene therapy strategies, even if transduction efficiency can be significantly improved. We propose the incorporation of chromatin insulators in the design of gene therapy vectors to overcome the problem of position effects. Chromatin insulators are protein-binding DNA elements that lack intrinsic promoter/enhancer activity but shelter genes from transcriptional influence of surrounding chromatin. The best characterized insulators are from Drosophila. We hypothesize that the important cellular function of chromatin organization is evolutionarily conserved and that human homologs to Drosophila insulator binding proteins such as the suppressor of Hairy-wing exist and can be cloned. Using these putative proteins, it should be possible to identify corresponding minimal binding sites with insulator activity. The design and incorporation of effective chromatin insulator sequences in the next generation of gene therapy vectors should lead to improved and more predictable expression of therapeutic transgenes and constitute an important step toward clinically effective gene therapy. We have previously described the development of oncoretrovirus vectors for human gamma-globin using a truncated beta-globin promoter, modified gamma-globin cassette, and alpha-globin enhancer. However, one of these vectors is genetically unstable, and both vectors exhibit variable expression patterns in cultured cells, common characteristics of oncoretrovirus vectors for globin genes. To address these problems, we identified and removed the vector sequences responsible for genetic instability and flanked the resultant vector with the chicken beta-globin HS4 chromatin insulator to protect expression from chromosomal position effects. After determining that flanking with the cHS4 element allowed higher, more uniform levels of gamma-globin expression in MEL cell lines, we tested these vectors using a mouse bone marrow transduction and transplantation model. When present, the gamma-globin cassettes from the uninsulated vectors were expressed in only 2% to 5% of red blood cells (RBCs) long term, indicating they are highly sensitive to epigenetic silencing. In contrast, when present the gamma-globin cassette from the insulated vector was expressed in 49% +/- 20% of RBCs long term. RNase protection analysis indicated that the insulated gamma-globin cassette was expressed at 23% +/- 16% per copy of mouse alpha-globin in transduced RBCs. These results demonstrate that flanking a globin vector with the cHS4 insulator increases the likelihood of expression nearly 10-fold, which in turn allows for gamma-globin expression approaching the therapeutic range for sickle cell anemia and beta thalassemia. Extensive gene therapy studies in preclinical models and in clinical trials underscore the relative safety of onco-retroviral vectors. Up until recently, no adverse effects have been reported in nearly 2000 patients that were enrolled in gene therapy clinical trials involving onco-retroviral vectors. However, the main safety concern of using onco-retroviral vectors is related to the risk of maligt transformation following oncogene activation due to random onco-retroviral genomic integration. Based on primate studies, there is an apparent low risk of maligcy that is predominately associated with the occurrence of chronic retroviremia resulting from replication-competent retroviruses (RCR), particularly in immunosuppressed recipient hosts. However, in the latest packaging cell lines and vectors, the risk of RCR-generation has been drastically reduced, primarily by minimizing the homologous overlap between vector and helper sequences. Nevertheless, results from a recent preclinical study in mice and a clinical trial in patients suffering from SCID-X1 strongly suggest that onco-retroviral vectors devoid of RCR can contribute to lymphomagenesis by insertional activation of cellular oncogenes. The risk of inadvertent germline transmission of onco-retroviral vectors appears to be low, especially relative to the endogenous rate of germline insertion, which is known to occur naturally in the human population via transmission of endogenous retro-transposons. The strict dependency of onco-retroviral gene transfer on cell division is an important safety advantage that significantly limits the risks of horizontal transmission. Since improved onco-retroviral vectors or transduction protocols may result in an increased number of retroviral integrations per cell, this may concomitantly increase the risk of maligt transformation. The use of suicide genes, self-inactivating vectors and/or chromosomal insulators is, therefore, warranted to further enhance the safety features of onco-retroviral vectors. Detailed analyses of insertion sites combined with long-term clinical follow-up may contribute to a more accurate risk assessment. The recent incidents of leukemia development in X-SCID patients after a successful treatment of the disease with retroviral gene therapy raised concerns regarding the safety of the use of retroviral vectors in clinical gene therapy. In this review, we have tried to re-evaluate the safety issues related to the use of retroviral vectors in human clinical trials and to suggest possible appropriate solutions to the issues. As revealed by the X-SCID incident, oncogenesis caused by retroviral insertional activation of host genes is one of the most prominent risks. An ultimate solution to this problem will be in re-engineering retroviral vectors so that the retroviral insertion takes place only at the desired specific sites of the host cell chromosome. This is, however, a technically demanding tasks, and it will take years to develop retroviral vectors with targeted insertion capability. In the mean time, the use of chromatin insulators can reduce chances for retrovirus-mediated oncogenesis by inhibiting non-specific activation of nearby cellular proto-oncogenes. Co-transduction of a suicidal gene under the control of an inducible promoter could also be one of the important safety features, since destruction of transduced cells can be triggered if abnormal growth is observed. Additionally, conditional expression of the transgene only in appropriate target cells via the combination of targeted transduction, cell type-specific expression, and targeted local administration will increase the overall safety of the retroviral systems. Finally, splitting of the viral genome, use of self-inactivating (SIN) retroviral vectors, or complete removal of the coding sequences for gag, pol, and env genes is desirable to virtually eliminate the possibility of generation of replication competent retroviruses (RCR). Silencing and position-effect (PE) variegation (PEV), which is due to integration of viral vectors in heterochromatin regions, are considered significant obstacles to obtaining a consistent level of transgene expression in gene therapy. The inclusion of chromatin insulators into vectors has been proposed to counteract this position-dependent variegation of transgene expression. Here, we show that the sea urchin chromatin insulator, sns5, protects a recombit gamma-retroviral vector from the negative influence of chromatin in erythroid milieu. This element increases the probability of vector expression at different chromosomal integration sites, which reduces both silencing and PEV. By chromatin immunoprecipitation (ChIP) analysis, we demonstrated the specific binding of GATA1 and OCT1 transcription factors and the enrichment of hyperacetylated nucleosomes to sns5 sequences. The results suggest that this new insulator is able to maintain a euchromatin state inside the provirus locus with mechanisms that are common to other characterized insulators. On the basis of its ability to function as barrier element in erythroid milieu and to bind the erythroid specific factor GATA1, the inclusion of sns5 insulator in viral vectors may be of practical benefit in gene transfer applications and, in particular, for gene therapy of erythroid disorders. Insertional mutagenesis has emerged as a major obstacle for gene therapy based on vectors that integrate randomly in the genome. Reducing the genotoxicity of genomic viral integration can, in first approximation, be equated with reducing the risk of oncogene activation, at least in the case of therapeutic payloads that have no known oncogenic potential, such as the globin genes. An attractive solution to the problem of oncogene activation is the inclusion of insulators/enhancer-blockers in the viral vectors. In this study we have used Recombinase-Mediated Cassette Exchange to characterize the effect of integration of globin therapeutic cassettes in the presence or absence of the chicken HS4 and three other putative insulators inserted near Stil, Tal1 and MAP17, three well-known cellular proto-oncogenes in the SCL/Tal1 locus. We show that insertion of a Locus Control Region-driven globin therapeutic globin transgene had a dramatic activating effect on Tal1 and Map17, the two closest genes, a minor effect on Stil, and no effect on Cyp4x1, a non-expressed gene. Of the four element tested, cHS4 was the only one that was able to suppress this transgene-mediated insertional transcriptional activation. cHS4 had a strong suppressive effect on the activation expression of Map17 but has little or no effect on expression of Tal1. The suppressive activity of cHS4 is therefore promoter specific. Importantly, the observed suppressive effect of cHS4 on Map17 activation did not depend on its intercalation between the LCR and the Map 17 promoter. Rather, presence of one or two copies of cHS4 anywhere within the transgene was sufficient to almost completely block the activation of Map17. Therefore, at this complex locus, suppression of transgene-mediated insertional transcriptional activation by cHS4 could not be adequately explained by models that predict that cHS4 can only suppress expression through an enhancer-blocking activity that requires intercalation between an enhancer and a promoter. This has important implications for our theoretical understanding of the possible effects of the insertion of cHS4 on gene therapy vectors. We also show that cHS4 decreased the level of expression of the globin transgene. Therefore, the benefits of partially preventing insertional gene activation are in part negated by the lower expression level of the transgene. A cost/benefit analysis of the utility of incorporation of insulators in gene therapy vectors will require further studies in which the effects of insulators on both the therapeutic gene and the flanking genes are determined at a large number of integration sites. Identification of insulators with minimal promoter specificity would also be of great value. Chromatin insulators separate active transcriptional domains and block the spread of heterochromatin in the genome. Studies on the chicken hypersensitive site-4 (cHS4) element, a prototypic insulator, have identified CTCF and USF-1/2 motifs in the proximal 250 bp of cHS4, termed the "core", which provide enhancer blocking activity and reduce position effects. However, the core alone does not insulate viral vectors effectively. The full-length cHS4 has excellent insulating properties, but its large size severely compromises vector titers. We performed a structure-function analysis of cHS4 flanking lentivirus-vectors and analyzed transgene expression in the clonal progeny of hematopoietic stem cells and epigenetic changes in cHS4 and the transgene promoter. We found that the core only reduced the clonal variegation in expression. Unique insulator activity resided in the distal 400 bp cHS4 sequences, which when combined with the core, restored full insulator activity and open chromatin marks over the transgene promoter and the insulator. These data consolidate the known insulating activity of the canonical 5' core with a novel 3' 400 bp element with properties similar to the core. Together, they have excellent insulating properties and viral titers. Our data have important implications in understanding the molecular basis of insulator function and design of gene therapy vectors. The therapeutic application of recombit retroviruses and other integrating gene transfer vectors has been limited by problems of vector expression and vector-mediated genotoxicity. These problems arise in large part from the interactions between vector sequences and the genomic environment surrounding sites of integration. Strides have been made in overcoming both of these problems through the modification of deleterious vector sequences, the inclusion of better enhancers and promoters, and the use of alternative virus systems. However, these modifications often add other restrictions on vector design, which in turn can further limit therapeutic applications. As an alternative, several groups have been investigating a class of DNA regulatory elements known as chromatin insulators. These elements provide a means of blocking the interaction between an integrating vector and the target cell genome in a manner that is independent of the vector transgene, regulatory elements, or virus of origin. This review outlines the background, rationale, and evidence for using chromatin insulators to improve the expression and safety of gene transfer vectors. Also reviewed are topological factors that constrain the use of insulators in integrating gene transfer vectors, alternative sources of insulators, and the role of chromatin insulators as one of several components for optimal vector design. Gene transfer-based therapeutic approaches have greatly benefited from the ability of some viral vectors to efficiently integrate within the cell genome and ensure persistent transmission of newly acquired transgenes to the target cell progeny. However, integration of provirus has been associated with epigenetic repercussions that may influence the expression of both the transgene and cellular genes close to vector integration loci. The exploitation of genetic insulator elements may overcome both issues through their ability to act as barriers that limit transgene silencing and/or as enhancer-blockers preventing the activation of endogenous genes by the vector enhancer. We established quantitative plasmid-based assay systems to screen enhancer-blocker and barrier genetic elements. Short synthetic insulators that bind to nuclear factor-I protein family transcription factors were identified to exert both enhancer-blocker and barrier functions, and were compared to binding sites for the insulator protein CTCF (CCCTC-binding factor). Gamma-retroviral vectors enclosing these insulator elements were produced at titers similar to their non-insulated counterparts and proved to be less genotoxic in an in vitro immortalization assay, yielding lower activation of Evi1 oncogene expression and reduced clonal expansion of bone marrow cells. Gene therapy for the treatment of Wiskott-Aldrich syndrome (WAS) presents an alternative to the current use of allogeneic bone marrow transplantation. We describe the development of a self-inactivating lentiviral vector containing chromatin insulators for treatment of WAS and compare a gammaretroviral (MND), human cellular (EF1α), and the human WASp gene promoter for expression patterns in vivo during murine hematopoiesis using the green fluorescent protein (GFP) marker. Compared with the EF1α and the WASp promoters, expression from the MND promoter in mouse transplant recipients was much higher in all lineages examined. Importantly, there was sustained expression in the platelets of secondary recipient animals, necessary to correct the thrombocytopenia defect in WAS patients. Analysis of WAS protein expression in transduced human EBV-immortalized B-cells and transduced patient peripheral blood mononuclear cells also demonstrated stronger expression per copy from the MND promoter compared with the other promoters. In addition, when analyzed in an LM02 activation assay, the addition of an insulator to MND-promoter-containing constructs reduced transactivation of the LM02 gene. We propose a clinical trial design in which cytokine-mobilized, autologous, transduced CD34(+) cells are administered after myelosuppression. Integrating and expressing stably a transgene into the cellular genome remain major challenges for gene-based therapies and for bioproduction purposes. While transposon vectors mediate efficient transgene integration, expression may be limited by epigenetic silencing, and persistent transposase expression may mediate multiple transposition cycles. Here, we evaluated the delivery of the piggyBac transposase messenger RNA combined with genetically insulated transposons to isolate the transgene from neighboring regulatory elements and stabilize expression. A comparison of piggyBac transposase expression from messenger RNA and DNA vectors was carried out in terms of expression levels, transposition efficiency, transgene expression and genotoxic effects, in order to calibrate and secure the transposition-based delivery system. Messenger RNA reduced the persistence of the transposase to a narrow window, thus decreasing side effects such as superfluous genomic DNA cleavage. Both the CTF/NF1 and the D4Z4 insulators were found to mediate more efficient expression from a few transposition events. We conclude that the use of engineered piggyBac transposase mRNA and insulated transposons offer promising ways of improving the quality of the integration process and sustaining the expression of transposon vectors.

Which deficiency is the cause of restless leg syndrome?

It has been well-documented that iron deficiency is the cause of restless leg syndrome. Magnesium and ferritin were also associated with restless leg syndrome.

INTRODUCTION: The restless legs syndrome is characterized by an unpleasant sensation in the legs which causes an imperative need to move the legs and is therefore considered to be a disorder of movement. When it appears before going to sleep, it may interfere with falling asleep and lead to a sleep-deficit. DEVELOPMENT AND CONCLUSIONS: It is a clinical condition with a satisfactory treatment, and improvement of the associated sleep disorder. The etiology is unknown, sometimes it is familial. The syndrome is increasingly often diagnosed, particularly in association with iron deficiency, during pregcy, in chronic renal failure and in patients with peripheral neuropathy. Polysomnography is not necessary, unless one suspects an associated disorder of periodic leg movements. Treatment is by dopaminergic, opiate, benzodiazepine, anticonvulsant drugs or clonidine. Periodic limb movement disorder (PLMD) is one of the commonest neurological disorders and causes significant disability, if left untreated. However, it is rarely diagnosed in clinical practice, probably due to lack of awareness and/or lack of necessary diagnostic facilities. Restless leg syndrome (RLS), aging, pregcy, uraemia, iron deficiency, polyneuropathy are some of the common causes of secondary PLMD. Clinical presentation, polysomnographic findings and management of six patients of PLMD have been discussed in this report. Prior studies have suggested a common etiology involved in Tourette's syndrome and several comorbid conditions and symptomatology. Reportedly, current medications used in Tourette's syndrome have intolerable side-effects or are ineffective for many patients. After thoroughly researching the literature, I hypothesize that magnesium deficiency may be the central precipitating event and common pathway for the subsequent biochemical effects on substance P, kynurenine, NMDA receptors, and vitamin B6 that may result in the symptomatology of Tourette's syndrome and several reported comorbid conditions. These comorbid conditions and symptomatology include allergy, asthma, autism, attention deficit hyperactivity disorder, obsessive compulsive disorder, coprolalia, copropraxia, anxiety, depression, restless leg syndrome, migraine, self-injurious behavior, autoimmunity, rage, bruxism, seizure, heart arrhythmia, heightened sensitivity to sensory stimuli, and an exaggerated startle response. Common possible environmental and genetic factors are discussed, as well as biochemical mechanisms. Clinical studies to determine the medical efficacy for a comprehensive magnesium treatment option for Tourette's syndrome need to be conducted to make this relatively safe, low side-effect treatment option available to doctors and their patients. Iron is the most important transitional metal in the body, as it is implicated in many metabolic processes, mostly related to its capacity as an electron donor/acceptor. Iron deficiency has been long been known to cause anaemia, iron excess to cause haemochromatosis. As excess free iron can cause oxidative damage, it is important that the levels of iron in the body are tightly regulated which appears to be done only by digestive absorption, as there is no known regulating mechanism for elimination of iron. The amount of free iron is also kept to a minimum thanks to binding to transferrin for transport, and to ferritin for storage. Recent research has put emphasis on the possible role of excess iron in the brain in several degenerative diseases. Iron deficiency in the central nervous system is known to cause motor impairment and cognitive deficits; more recently, it has been suggested that it may play a role in the pathophysiology of the restless leg syndrome. 2001 Harcourt Publishers Ltd Diurnal effects on motor control are evident in the human disease of Restless Leg Syndrome (RLS), which is purported to be linked to brain iron deficiency as well as alterations in dopaminergic systems. Thus, we explored the relationship between daily rhythms, the onset of motor dysregulation and brain iron deficiency in an animal model of iron deficiency. Male and female weanling Sprague-Dawley rats consuming control (CN) or iron-deficient (ID) diets were examined weekly for acoustic startle response (ASR) and prepulse inhibition (PPI) for a 5-week period. Iron deficiency reduced the magnitude, but not timing, of the ASR at specific time points. ASR was elevated 60% at the onset of the dark cycle relative to the median of the light cycle in male CN and ID rats. The respective elevation was 400% and 150% in female CN and ID rats during the first 2 weeks of testing. The diurnal cycle of ASR response was attenuated by 3 weeks of testing in both dietary treatment groups. PPI was not affected by iron deficiency, sex, diurnal cycle or the interaction between these factors. These results thus demonstrate that iron deficiency moderately alters ASR signaling although the inhibitory pathways of ASR do not appear to be affected. Restless leg syndrome (RLS) and periodic limb movement disorder (PLMD) are considered to be a continuum of a neurological sleep disorder associated with abnormal iron metabolism or deficiency. I describe a case of RLS and PLMD in a cystic fibrosis patient with iron deficiency from chronic hemoptysis. This is the first case that reports RLS and PLMD manifesting from iron deficiency caused by chronic hemoptysis in advanced cystic fibrosis lung disease. Restless legs syndrome (RLS) is a common condition that is frequently unrecognized, misdiagnosed and poorly managed. It is characterized by uncomfortable sensations deep in the legs developing at rest that compel the person to move; symptoms are worst at night and sleep disturbance is common. RLS occurs in 7%-11% of the population in Western countries, and many such people experience troublesome symptoms. Primary RLS is familial in up to two thirds of patients. RLS may also be secondary to a number of conditions including iron deficiency, pregcy and end-stage renal failure and, perhaps, neuropathy. Secondary RLS is most common in those presenting for the first time in later life. The pathogenesis of RLS probably involves the interplay of systemic or brain iron deficiency and impaired dopaminergic neurotransmission in the subcortex of the brain. RLS is very responsive to dopaminergic therapies. Rebound of RLS symptoms during the early morning and development of severe symptoms earlier in the day (augmentation) are problematic in those treated for a prolonged period with levodopa. Consequently, dopamine agonists have become first line treatment. Anti-convulsant medications and opioids are helpful in some patients. Correction of underlying problem wherever possible is important in the management of secondary RLS. Restless legs syndrome (RLS) has gradually been recognized as a cause for insomnia in adults, but there have been few reports about children with RLS in Japan. Here we described seven pediatric RLS patients. All of the parents of our patients had difficult times to make their children sleep due to irritability, restlessness, and demanding bedtime routines. All patients had asked their parents to rub their feet in bed, and it took more than half an hour to soothe them until they fell asleep. Their mothers had been exhausted from this night-time routine. However, they did not consider the routine abnormal, as it had been their habitual behavior since infancy. Some parents were too distressed or embarrassed to describe the symptoms of their child properly. Five patients had clear family history and none had obvious periodic leg movements during sleep. All patients showed low levels of ferritin and iron supplementation was effective in five cases. In the severest two cases, pramipexole, but not iron, was dramatically effective. Both patients started to show RLS symptoms in the early days of infancy, which may suggest more severe hereditary dopaminergic dysfunction. RLS does occur in childhood and pediatricians should bear it in mind as one of the differential diagnoses when seeing children who are irritated and/or having difficulty in initiating their sleep. Restless leg syndrome (RLS) is a sensorimotor disorder. Clinical studies have implicated the dopaminergic system in RLS, while others have suggested that it is associated with insufficient levels of brain iron. To date, alterations in brain iron status have been demonstrated but, despite suggestions from the clinical literature, there have been no consistent findings documenting a dopaminergic abnormality in RLS brain tissue. In this study, the substantia nigra and putamen were obtained at autopsy from individuals with primary RLS and a neurologically normal control group. A quantitative profile of the dopaminergic system was obtained. Additional assays were performed on a catecholaminergic cell line and animal models of iron deficiency. RLS tissue, compared with controls, showed a significant decrease in D2R in the putamen that correlated with severity of the RLS. RLS also showed significant increases in tyrosine hydroxylase (TH) in the substantia nigra, compared with the controls, but not in the putamen. Both TH and phosphorylated (active) TH were significantly increased in both the substantia nigra and putamen. There were no significant differences in either the putamen or nigra for dopamine receptor 1, dopamine transporters or for VMAT. Significant increases in TH and phosphorylated TH were also seen in both the animal and cell models of iron insufficiency similar to that from the RLS autopsy data. For the first time, a clear indication of dopamine pathology in RLS is revealed in this autopsy study. The results suggest cellular regulation of dopamine production that closely matches the data from cellular and animal iron insufficiency models. The results are consistent with the hypothesis that a primary iron insufficiency produces a dopaminergic abnormality characterized as an overly activated dopaminergic system as part of the RLS pathology. There may be a relationship between proton pump inhibitors (PPIs) and iron absorption. PPIs may decrease the amount of iron absorbed gastrointestinally specifically due to alteration of the pH in the duodenum. Restless legs syndrome (RLS) is a sensorimotor disorder that includes an urge to move legs, accompanied or caused by uncomfortable and unpleasant sensations in the legs; the urge to move begins or worsens during periods of rest or inactivity, the urge to move is partially or totally relieved by movement, and the urge is worse or only occurs at night. In the majority of the restless leg syndrome population, the sensation is deep seated, often described as being in the shin bones, and most commonly felt between the knee and ankle. It may be described as a creepy, shock-like, tense, electric, buzzing, itchy, or even numb sensation. A subpopulation of this restless leg syndrome patient population experiences restless leg syndrome associated pain (RLSAP) that has been described as a deep "achy pain." This pain has not been found to be relieved by many of the typical over the counter analgesics. Often, constant movement of the legs appears to be the only remedy, as these sensations usually appear during periods of rest. Furthermore, there appears to be an association between iron deficiency and those suffering from Restless Leg Syndrome (RLS). The authors theorize that there may be a possible correlation between PPIs and the symptoms (e.g. pain) associated with RLS. The authors propose that PPIs, such as omeprazole, may interfere with iron absorption in certain patients and that a subpopulation of patients who develop significant iron deficiency characterized by low serum ferritin levels while on PPIs may also develop RLS-like symptoms (including RLSAP). While there is no robust direct evidence to support any associations of PPIs and iron deficiency or PPIs associated with RLS-like symptoms (including RLSAP), it is hoped that this manuscript may spark research efforts on this issue. BACKGROUND AND OBJECTIVES: Iron depletion is common in regular blood donors. The objective of the study was to investigate the frequency and severity of iron depletion in regular blood donors and whether IV iron is more effective than oral to avoid iron depletion and symptoms thereof, especially restless legs syndrome (RLS). METHOD: One hundred and twenty blood donors with at least five previous whole blood donations were randomized to receive either IV iron sucrose (Venofer(®), RenaPharma/Vifor, Uppsala, Sweden), 200 mg, or to 20×100 mg of oral iron sulphate (Duroferon(®), GlaxoSmithKline, Stockholm, Sweden), after each blood donation during 1 year. Iron status and RLS incidence and severity were investigated. RESULTS: Iron status was generally poor among regular blood donors, especially in women, with a high incidence of iron depletion (>20%) and RLS (18%). The IV iron group increased storage iron to a greater extent than the oral iron group after 12 months (P=0·0043). Female donors were more responsive to IV iron sucrose compared to oral iron sulphate, particularly female donors below 50 years of age. RLS severity scores were significantly lower in the IV iron group. The two treatments were safe. CONCLUSION: Iron status is poor in regular blood donors, restless legs syndrome is common, and the routine iron supplementation is insufficient. IV iron sucrose substitutes iron loss in blood donors more efficiently compared with oral iron sulphate, especially in women. Iron substitution to blood donors should be individualized and based on P-ferritin monitoring. Restless legs syndrome is a neurological disorder characterized by an urgency to move the legs during periods of rest. Data from a variety of sources provide a compelling argument that the amount of iron in the brain is lower in individuals with restless legs syndrome compared with neurologically normal individuals. Moreover, a significant percentage of patients with restless legs syndrome are responsive to intravenous iron therapy. The mechanism underlying the decreased iron concentrations in restless legs syndrome brains is unknown. We hypothesize that the source of the brain iron deficit is at the blood-brain interface. Thus we analysed the expression of iron management proteins in the epithelial cells of the choroid plexus and the brain microvasculature in post-mortem tissues. The choroid plexus, obtained at autopsy, from 18 neurologically normal controls and 14 individuals who had primary restless legs syndrome was subjected to histochemical staining for iron and immunostaining for iron management proteins. Iron and heavy chain ferritin staining was reduced in the epithelial cells of choroid plexus in restless legs syndrome. Divalent metal transporter, ferroportin, transferrin and its receptor were upregulated in the choroid plexus in restless legs syndrome. Microvessels were isolated from the motor cortex of 11 restless legs syndrome and 14 control brains obtained at autopsy and quantitative immunoblot analyses was performed. Expression of heavy chain ferritin, transferrin and its receptor in the microvessels from restless legs syndrome was significantly decreased compared with the controls but divalent metal protein 1, ferroportin, prohepcidin, mitochondrial ferritin and light-chain ferritin remained unchanged. The presence of an iron regulatory protein was demonstrated in the brain microvasculature and the activity of this protein is decreased in restless legs syndrome; a finding similar to our earlier report in neuromelanin cells from the substantia nigra of restless legs syndrome brains. This study reveals that there are alterations in the iron management protein profile in restless legs syndrome compared with controls at the site of blood-brain interface suggesting fundamental differences in brain iron acquisition in individuals with restless legs syndrome. Furthermore, the decrease in transferrin receptor expression in the microvasculature in the presence of relative brain iron deficiency reported in restless legs syndrome brains may underlie the problems associated with brain iron acquisition in restless legs syndrome. The consistent finding of loss of iron regulatory protein activity in restless legs syndrome brain tissue further implicates this protein as a factor in the underlying cause of the iron deficiency in the restless legs syndrome brain. The data herein provide evidence for regulation of iron uptake and storage within brain microvessels that challenge the existing paradigm that the blood-brain barrier is merely a transport system. Insomnia has become a major public health issue in recent times. Although quality of sleep is affected by environmental, psychophysiological, and pharmacological factors, diet and nutrient intake also contribute to sleep problems. This study investigated the association between nutrient intake and co-morbid symptoms associated with sleep status among selected adults. Subjects in this study included 87 men and women aged 21-45 years. Presence of insomnia was assessed using the Insomnia Screening Questionnaire, and dietary intake was measured over three consecutive days by dietary survey. Descriptive analysis, ANOVA, and Chi-Square tests were performed to compute and interpret the data. Approximately 60% of the participants were insomniacs. People with insomnia consumed significantly lesser quantities of nutrients as compared to normal sleepers. Differences in intakes of energy, carbohydrates, folic acid, and B(12) were highly significant (P < 0.002). Further, intakes of protein, fat, and thiamine were significantly different (P < 0.021) between insomniacs and normal sleepers. The nutrient intake pattern of the insomniacs with co-morbid symptoms was quite different from that of the normal sleepers. Based on these results, it is probable that there is an association between nutrition deficiency, co-morbid symptoms, and sleep status. More studies are required to confirm these results. Restless legs syndrome is common in patients with multiple sclerosis but has not been reported as occurring due to an acute, inflammatory, demyelinating attack. Restless legs syndrome is known to be related to low brain iron levels. Multiple sclerosis has been associated with the abnormal accumulation of iron in the chronic, progressive phase of axonal degeneration. Iron deficiency may play a role in demyelination. This suggests that restless legs syndrome may be caused by the inflammatory, demyelinating component of multiple sclerosis rather than axonal degeneration. The author presents a case of self-limited restless legs syndrome occurring as an acute attack of multiple sclerosis, supporting the notion that inflammatory demyelination is the underlying pathophysiology of restless legs syndrome in multiple sclerosis. BACKGROUND: Iron deficiency is a frequent side effect of blood donation. In recent years, several studies have described genetic variants associated with iron concentrations. However, the impact of these variants on iron levels is unknown in blood donors. Knowledge of genetic variants that predispose donors to iron deficiency would allow bleeding frequency and iron supplementation to be tailored to the individual donor. STUDY DESIGN AND METHODS: The genotypes of five specific single-nucleotide polymorphisms (SNPs) in three genes that have been previously associated with iron status and/or restless leg syndrome (RLS) were investigated in two groups of female blood donors. The first group had low iron stores (serum ferritin ≤ 12 µg/L, n = 657), and the second group had normal to high iron stores (serum ferritin > 30 µg/L, n = 645). Genotype distribution for each of the SNPs was compared between the two groups. RESULTS: Homozygosity for the T-allele of BTBD9 rs9296249 was associated with lower serum ferritin. The odds ratio for low serum ferritin was 1.35 (95% confidence interval, 1.02-1.77; p = 0.03) when comparing donors with the TT genotype with donors with the CT genotype. CONCLUSION: A frequent polymorphism in BTBD9 was significantly associated with serum ferritin. This polymorphism has previously been associated with RLS, but not low iron stores in blood donors. Willis-Ekbom's disease (WED), formerly called restless legs syndrome, is more common in pregt than in non-pregt women, implying that the physiological and biochemical changes during pregcy influence its development. During pregcy, many hormone levels undergo significant changes, and some hormones significantly increase in activity and can interfere with other hormones. For example, the steroid hormone estradiol interferes with the neuroendocrine hormone dopamine. During pregcy, the activity of the thyroid axis is enhanced to meet the increased demand for thyroid hormones during this state. Dopamine is a neuroendocrine hormone that diminishes the levels of thyrotropin and consequently of thyroxine, and one of the roles of the dopaminergic system is to counteract the activity of thyroid hormones. When the activity of dopamine is not sufficient to modulate thyroid hormones, WED may occur. Robust evidence in the medical literature suggests that an imbalance between thyroid hormones and the dopaminergic system underpins WED pathophysiology. In this article, we present evidence that this imbalance may also mediate transient WED during pregcy. It is possible that the main hormonal alteration responsible for transient WED of pregcy is the excessive modulation of dopamine release in the pituitary stalk by estradiol. The reduced quantities of dopamine then cause decreased modulation of thyrotropin, leading to enhanced thyroid axis activity and subsequent WED symptoms. Iron deficiency may also be a predisposing factor for WED during pregcy, as it can both diminish dopamine and increase thyroid hormone. The ubiquitously expressed iron storage protein ferritin plays a central role in maintaining cellular iron homeostasis. Cytosolic ferritins are composed of heavy (H) and light (L) subunits that co-assemble into a hollow spherical shell with an internal cavity where iron is stored. The ferroxidase activity of the ferritin H chain is critical to store iron in its Fe3+ oxidation state, while the L chain shows iron nucleation properties. We describe a unique case of a 23-yr-old female patient affected by a homozygous loss of function mutation in the L-ferritin gene, idiopathic generalized seizures, and atypical restless leg syndrome (RLS). We show that L chain ferritin is undetectable in primary fibroblasts from the patient, and thus ferritin consists only of H chains. Increased iron incorporation into the FtH homopolymer leads to reduced cellular iron availability, diminished levels of cytosolic catalase, SOD1 protein levels, enhanced ROS production and higher levels of oxidized proteins. Importantly, key phenotypic features observed in fibroblasts are also mirrored in reprogrammed neurons from the patient's fibroblasts. Our results demonstrate for the first time the pathophysiological consequences of L-ferritin deficiency in a human and help to define the concept for a new disease entity hallmarked by idiopathic generalized seizure and atypical RLS. BACKGROUND AND PURPOSE: It is not clear which is preferred between iron supplement and a dopamine agonist in the treatment of restless legs syndrome (RLS) with iron deficiency. The efficacies of oral iron supplementation and pramipexole for treatment of RLS with low-normal serum ferritin (15-50 ng/ml) were compared. METHODS: Thirty RLS patients who took either oral iron or pramipexole for 12 weeks and were followed at 2, 4, 8 and 12 weeks after treatment commencement were enrolled. Severities of RLS symptoms were assessed using the international RLS study group rating scale for severity (IRLS) at every visit. Treatment response was defined as a decrease in IRLS score of at least 50% from baseline. RESULTS: The 30 subjects were assigned equally to an iron or pramipexole group. At baseline, IRLS scores and serum ferritin levels were similar between these two groups. After 12 weeks, IRLS scores were lower than those at baseline in both groups (iron -9.1 ± 7.07, P < 0.001; pramipexole -8.7 ± 8.31, P = 0.001) and similar between the two groups. Changes in IRLS scores from baseline were similar between the two groups at each visit. The response rates of the groups were identical at 46.7%. CONCLUSIONS: Pramipexole was not different from oral iron in terms of efficacy and improvement speed in RLS patients with a low-normal serum ferritin, but response rate of either oral iron or pramipexole alone was moderate. Some proportion of RLS patients with iron deficiency might benefit from combined use of oral iron and dopamine agonists.

What histone modification is recognized by the bromodomain?

Acetylated lysines in histones (generally H3 and H4)

The coordination of chromatin remodeling with chromatin modification is a central topic in gene regulation. The yeast chromatin remodeling complex RSC bears multiple bromodomains, motifs for acetyl-lysine and histone tail interaction. Here, we identify and characterize Rsc4 and show that it bears tandem essential bromodomains. Conditional rsc4 bromodomain mutations were isolated, and were lethal in combination with gcn5Delta, whereas combinations with esa1 grew well. Replacements involving Lys14 of histone H3 (the main target of Gcn5), but not other H3 or H4 lysine residues, also conferred severe growth defects to rsc4 mutant strains. Importantly, wild-type Rsc4 bound an H3 tail peptide acetylated at Lys14, whereas a bromodomain mutant derivative did not. Loss of particular histone deacetylases suppressed rsc4 bromodomain mutations, suggesting that Rsc4 promotes gene activation. Furthermore, rsc4 mutants displayed defects in the activation of genes involved in nicotinic acid biosynthesis, cell wall integrity, and other pathways. Taken together, Rsc4 bears essential tandem bromodomains that rely on H3 Lys14 acetylation to assist RSC complex for gene activation. Bromodomain factor 1 (Bdf1) associates with Saccharomyces cerevisiae TFIID and corresponds to the C-terminal half of higher eukaryotic TAF1. It also associates with the SWR-C complex, which is important for Htz1 deposition. Bdf1 binds preferentially to acetylated histone H4. Bdf1 is phosphorylated, but the mechanism and significance of this modification have been unclear. Two distinct regions within Bdf1 are phosphorylated; one is just C terminal to the bromodomains and the other is near the C terminus. Mutational analysis shows that phosphorylation is necessary for Bdf1 function in vivo. Endogenous protein kinase CK2 purifies with Bdf1 and phosphorylates both domains. A similar mechanism may be responsible for phosphorylation of the C-terminal region of mammalian TAF1. These findings suggest that CK2 phosphorylation of Bdf1 may regulate RNA polymerase II transcription and/or chromatin structure. Lysine acetylation has been shown to occur in many protein targets, including core histones, about 40 transcription factors and over 30 other proteins. This modification is reversible in vivo, with its specificity and level being largely controlled by signal-dependent association of substrates with acetyltransferases and deacetylases. Like other covalent modifications, lysine acetylation exerts its effects through "loss-of-function" and "gain-of-function" mechanisms. Among the latter, lysine acetylation generates specific docking sites for bromodomain proteins. For example, bromodomains of Gcn5, PCAF, TAF1 and CBP are able to recognize acetyllysine residues in histones, HIV Tat, p53, c-Myb or MyoD. In addition to the acetyllysine moiety, the flanking sequences also contribute to efficient recognition. The relationship between acetyllysine and bromodomains is reminiscent of the specific recognition of phosphorylated residues by phospho-specific binding modules such as SH2 domains and 14-3-3 proteins. Therefore, lysine acetylation forges a novel signaling partnership with bromodomains to govern the temporal and spatial regulation of protein functions in vivo. Studies showed that the bromodomain binds to acetyl-lysines on histone tails, which is involved in deciphering the histone codes. BRD7, a novel bromodomain gene, is the first described bromodomain gene involved in nasopharyngeal carcinoma (NPC). Previous studies showed that ectopic expression of BRD7 inhibited cell growth and cell cycle progression from G1 to S phase in HNE1 cells (a NPC cell line) by transcriptionally regulating some cell cycle related genes including E2F3 gene. In the present study, we revealed the co-localization between acetylated H3 and BRD7 and found that the bromodomain of BRD7 is required for this co-localization. More importantly, wild-type BRD7 interacted with H3 peptide acetylated at Lys14, while the bromodomain deleted mutant lost this ability. We also found that the mutant BRD7 failed to regulate E2F3 promoter activity and inhibit cell cycle progression. These results indicated that the transcriptional regulation role of BRD7 was achieved by binding to acetylated histone H3 and that the bromodomain was essential for this role. In addition, no obvious changes were observed in the acetylated level of histone H3 after transfection with BRD7, indicating that chromatin remodeling, not chromatin modification, is the major mechanism of BRD7 mediated gene transcription. Taken together, the present work shed light on the fact that a novel bromodomain gene, BRD7, is of importance in transcriptional regulation and cellular events including cell cycle. Bromodomains are present in many chromatin-associated proteins such as the SWI/SNF and RSC chromatin remodelling and the SAGA HAT (histone acetyltransferase) complexes, and can bind to acetylated lysine residues in the N-terminal tails of the histones. Lysine acetylation is a histone modification that forms a stable epigenetic mark on chromatin for bromodomain-containing proteins to dock and in turn regulate gene expression. In order to better understand how bromodomains read the 'histone code' and interact with acetylated histones, we have tested the interactions of several bromodomains within transcriptional co-activators with differentially acetylated histone tail peptides and HAT-acetylated histones. Using GST (glutathione S-transferase) pull-down assays, we show specificity of binding of some bromodomains to differentially acetylated H3 and H4 peptides as well as HAT-acetylated histones. Our results reveal that the Swi2/Snf2 bromodomain interacts with various acetylated H3 and H4 peptides, whereas the Gcn5 bromodomain interacts only with acetylated H3 peptides and tetra-acetylated H4 peptides. Additionally we show that the Spt7 bromodomain interacts with acetylated H3 peptides weakly, but not with acetylated H4 peptides. Some bromodomains such as the Bdf1-2 do not interact with most of the acetylated peptides tested. Results of the peptide experiments are confirmed with tests of interactions between these bromodomains and HAT-acetylated histones. Furthermore, we demonstrate that the Swi2/Snf2 bromodomain is important for the binding and the remodelling activity of the SWI/SNF complex on hyperacetylated nucleosomes. The selective recognition of the bromodomains observed in the present study accounts for the broad effects of bromodomain-containing proteins observed on binding to histones. Double bromodomain proteins bind to acetylated lysines in histones, bringing associated histone modification and nucleosome remodeling activity to chromatin. The ability of bromodomain regulators to alter chromatin status and control gene expression has long been appreciated to be important in the development of certain human cancers. However, bromodomain proteins have now been found also to be critical, non-redundant players in diverse, non-maligt phenotypes, directing transcriptional programs that control adipogenesis, energy metabolism and inflammation. The fact that such different processes are functionally linked by the same molecular machinery suggests a common epigenetic basis to understand and interpret the origins of several important co-morbidities, such as asthma or cancer that occurs in obesity, and complex inflammatory diseases like cardiovascular disease, systemic lupus erythematosus, rheumatoid arthritis and insulin resistance that may be built on a common pro-inflammatory foundation. The CREB binding protein (CBP) is a human transcriptional coactivator consisting of several conserved functional modules, which interacts with distinct transcription factors including nuclear receptors, CREB, and STAT proteins. Despite the importance of CBP in transcriptional regulation, many questions regarding the role of its particular domains in CBP functions remain uswered. Therefore, developing small molecules capable of selectively modulating a single domain of CBP is of invaluable aid at unraveling its prominent activities. Here we report the design, synthesis, and biological evaluation of conformationally restricted peptides as novel modulators for the acetyl-lysine binding bromodomain (BRD) of CBP. Utilizing a target structure-guided and computer-aided rational design approach, we developed a series of cyclic peptides with affinity for CBP BRD significantly greater than those of its biological ligands, including lysine-acetylated histones and tumor suppressor p53. The best cyclopeptide of the series exhibited a K(d) of 8.0 μM, representing a 24-fold improvement in affinity over that of the linear lysine 382-acetylated p53 peptide. This lead peptide is highly selective for CBP BRD over BRDs from other transcriptional proteins. Cell-based functional assays carried out in colorectal carcinoma HCT116 cells further demonstrated the efficacy of this compound to modulate p53 stability and function in response to DNA damage. Our results strongly argue that these CBP modulators can effectively inhibit p53 transcriptional activity by blocking p53K382ac binding to CBP BRD and promoting p53 instability by changes of its post-translational modification states, a different mechanism than that of the p53 inhibitors reported to date. The posttranslational modification of chromatin through acetylation at selected histone lysine residues is governed by histone acetyltransferases (HATs) and histone deacetylases (HDACs). The significance of this subset of the epigenetic code is interrogated and interpreted by an acetyllysine-specific protein-protein interaction with bromodomain reader modules. Selective inhibition of the bromo and extra C-terminal domain (BET) family of bromodomains with a small molecule is feasible, and this may represent an opportunity for disease intervention through the recently disclosed antiproliferative and anti-inflammatory properties of such inhibitors. Herein, we describe the discovery and structure-activity relationship (SAR) of a novel, small-molecule chemical probe for BET family inhibition that was identified through the application of structure-based fragment assessment and optimization techniques. This has yielded a potent, selective compound with cell-based activity (PFI-1) that may further add to the understanding of BET family function within the bromodomains.

What memory problems are reported in the " Gulf war syndrome"?

Loss of memory and dysmnesia are memory problems reported in the " Gulf war syndrome". Patients suffering from this syndrome often have other nonspecific symptoms such as fatigue, skin rash, headache, muscle and joint pain and sexual dysfunction.

BACKGROUND: Numerous questions have been raised about the health consequences to veterans of the Gulf War but most particularly to issues concerning women, who were deployed in unprecedented numbers. Little is known about the health consequences to women of wartime stressors, in general, or the environmental and job-related exposures specific to the theater of the Gulf War. METHODS: A stratified sample of 525 women participated in the study following the war and again in a follow-up study 2 yr later. The sampling frame was stratified on component of the U.S. Air Force (active, guard or reserve), deployment (in the theater or elsewhere), and parental status (parent or nonparent). Measures included items concerning general physical health, gender-specific health, the "Gulf War Syndrome," and the emotional responses to war, including symptoms of post-traumatic stress disorder (PTSD). RESULTS: Multiple statistical analyses were used to describe women's physical and emotional health at two time points following the war. Women deployed to the theater reported significantly more general as well as gender-specific health problems than did women deployed elsewhere. A cluster of common health problems included: skin rash, cough, depression, unintentional weight loss, insomnia, and memory problems. Women serving in the theater also reported a significant increase in several gender-specific problems compared to women deployed elsewhere. CONCLUSIONS: Findings suggest the need for follow-up of a cluster of specific health effects, including those concerning gynecologic and reproductive health. The Gulf War syndrome represents neurological and neuropsychological disorders in veterans of the Persian Gulf war. Until today, the various symptoms observed could not be attributed to any defined disease. As a possible cause, exposure to neurotoxic agents such as the organophosphates used during the war has been suggested by many authors. We report on a 29-year-old man who suffered from dysmnesia, disturbance of orientation, cognitive impairment, and double vision. His history revealed several front-line operations in 1990 and 1991 during the Gulf War. Physical examinations showed a complex eye-movement disturbance and a horizontal nystagmus, which was neuro-ophthalmologically confirmed. The early auditory potentials referred to a brainstem dysfunction and the cognitive disturbances correlated to changes in the late-appearing component of event-related potentials (P 300). Brain imaging with CCT, MRI, SPECT, PET, and EEG and CSF showed no pathologies. Neuropsychological tests disclosed severe cognitive impairment especially concerning memory. Three-month follow-up studies in a department of psychosomatic medicine excluded a dissociative disorder as a feature of a post-traumatic stress or a conversion disorder. This is the first case of Gulf War syndrome in Germany. We focus on an unfamiliar complication after the war. The recent literature is reviewed. In early 1992, U.S. troops returning from the Gulf War began reporting a variety of nonspecific symptoms such as fatigue, skin rash, headache, muscle and joint pain, and loss of memory. These reports marked the beginning of what was to be identified as the Gulf War Syndrome (GWS). In the years since the war, as many as 100,000 troops have claimed they suffer from this mysterious disease. In our culture, the existence of disease as a specific entity is fundamental to ensuring the validity of that disease. The legitimacy of GWS has been repeatedly called into question because no specific physiological etiology has been confirmed, and it is becoming more and more likely that the origin of GWS will never be clearly delineated. The purpose of this paper is to illustrate the complicated process of defining GWS as a legitimate illness in the absence of etiological evidence and to suggest a method of treatment for individuals who still suffer from its sequelae. As part of a comprehensive multispecialty project, the present study reports on the neurocognitive and psychological function of veterans who report Persian Gulf War-related symptoms. The neuropsychological and psychological performances of 26 ill Gulf War veterans were compared to 20 well veterans from the same military unit. Neurocognitive functions assessed included intelligence, abstraction and problem-solving, attention and concentration, memory and learning, language and visual-spatial function, and sensorimotor abilities. Psychological function was measured by self-report questionnaires. Results indicated global and consistently poorer intellectual and neurocognitive function among the ill veterans compared to the control veterans. A generalized pattern of neuropsychological deficit was evident for the ill veterans. Psychological profiles of the ill veterans were similar to those in general medical patients. Based on these findings and results from the multispecialty investigation, we conclude that some of the ill veterans have experienced neurotoxic injury resulting in chronic neuropsychological impairment that is related to their service in the Persian Gulf War. BACKGROUND: Forces deployed to the first Gulf War report more ill health than veterans who did not serve there. Many studies of post-Gulf morbidity are based on relatively small sample sizes and selection bias is often a concern. In a setting where selection bias relating to the ill health of veterans may be reduced, we: i) examined self-reported adult ill health in a large sample of male UK Gulf War veterans and a demographically similar non-deployed comparison group; and ii) explored self-reported ill health among veterans who believed that they had Gulf War syndrome. METHODS: This study uses data from a retrospective cohort study of reproduction and child health in which a validated postal questionnaire was sent to all UK Gulf War veterans (GWV) and a comparison cohort of Armed Service personnel who were not deployed to the Gulf (NGWV). The cohort for analysis comprises 42,818 males who responded to the questionnaire. RESULTS: We confirmed that GWV report higher rates of general ill health. GWV were significantly more likely to have reported at least one new medical symptom or disease since 1990 than NGWV (61% versus 37%, OR 2.7, 95% CI 2.5-2.8). They were also more likely to report higher numbers of symptoms. The strongest associations were for mood swings (OR 20.9, 95%CI 16.2-27.0), memory loss/lack of concentration (OR 19.6, 95% CI 15.5-24.8), night sweats (OR 9.9, 95% CI 6.5-15.2), general fatigue (OR 9.6, 95% CI 8.3-11.1) and sexual dysfunction (OR 4.6, 95%CI 3.2-6.6). 6% of GWV believed they had Gulf War syndrome (GWS), and this was associated with the highest symptom reporting. CONCLUSIONS: Increased levels of reported ill health among GWV were confirmed. This study was the first to use a questionnaire which did not focus specifically on the veterans' symptoms themselves. Nevertheless, the results are consistent with those of other studies of post-Gulf war illness and thus strengthen overall findings in this area of research. Further examination of the mechanisms underlying the reporting of ill health is required. BACKGROUND: At least one-fourth of U.S. veterans who served in the 1990-1991 Gulf War are affected by the chronic symptomatic illness known as Gulf War illness (GWI). Clear determination of the causes of GWI has been hindered by many factors, including limitations in how epidemiologic studies have assessed the impact of the complex deployment environment on veterans' health. OBJECTIVE: We sought to address GWI etiologic questions by evaluating the association of symptomatic illness with characteristics of veterans' deployment. METHODS: We compared veteran-reported wartime experiences in a population-based sample of 304 Gulf War veterans: 144 cases who met preestablished criteria for GWI and 160 controls. Veteran subgroups and confounding among deployment variables were considered in the analyses. RESULTS: Deployment experiences and the prevalence of GWI differed significantly by veterans' location in theater. Among personnel who were in Iraq or Kuwait, where all battles took place, GWI was most strongly associated with using pyridostigmine bromide pills [odds ratio (OR) = 3.5; 95% confidence interval (CI): 1.7, 7.4] and being within 1 mile of an exploding SCUD missile (OR = 3.1; 95% CI: 1.5, 6.1). For veterans who remained in support areas, GWI was significantly associated only with personal pesticide use, with increased prevalence (OR = 12.7; 95% CI: 2.6, 61.5) in the relatively small subgroup that wore pesticide-treated uniforms, nearly all of whom also used skin pesticides. Combat service was not significantly associated with GWI. CONCLUSIONS: Findings support a role for a limited number of wartime exposures in the etiology of GWI, which differed in importance with the deployment milieu in which veterans served.

Is cadasil syndrome a hereditary disease?

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebral small vessel disease, clinically characterized by migraine, recurrent transient ischemic attacks or strokes, psychiatric disorders and cognitive decline. Strokes are typically ischemic, while hemorrhagic events have been only sporadically described. CADASIL is the most common form of hereditary cerebral angiopathy.

Cerebral autosomal domit arteriopathy with subcortical infarct and leukoencephalopathy: A rare syndrome raising anesthetic concerns! BACKGROUND: The National Institutes of Health Stroke Scale (NIHSS) is widely used to measure neurological deficits, evaluate the effectiveness of treatment and predict outcome in acute ischemic stroke. It has also been used to measure the residual neurological deficit at the chronic stage after ischemic events. However, the value of NIHSS in ischemic cerebral small vessel disease has not been specifically evaluated. The purpose of this study was to investigate the link between the NIHSS score and clinical severity in a large population of subjects with CADASIL (cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy), a unique model to investigate the pathophysiology and natural history of ischemic small vessel disease. METHODS: Demographic and clinical data of 220 patients with one or more lacunar infarcts confirmed by MRI examination and enrolled from a prospective cohort study were analyzed. Detailed neurological examinations, including evaluation of the NIHSS and modified Rankin Scale score (mRS) for evaluating the clinical severity, were performed in all subjects. The sensitivity, specificity, positive and negative predictive values of various NIHSS thresholds to capture the absence of significant disability (mRS <3) were calculated. General linear models, controlling for age, educational level and different clinical manifestations frequently observed in CADASIL, were used to evaluate the relationships between NIHSS and clinical severity. RESULTS: In the whole cohort, 45 (20.5%) subjects presented with mRS ≥3, but only 16 (7.3%) had NIHSS >5. All but 1 subject with NIHSS >5 showed mRS ≥3. NIHSS ≤5 had an 85.3% positive predictive value for no or slight disability with only 33.3% specificity. The NIHSS, MMSE score and presence or absence of gait disturbances were found to be strongly and independently correlated with disability (all p < 0.001). Altogether, they accounted for 73% of the variance of mRS in contrast with the NIHSS alone accounting for only 50% of this variance. Among patients with NIHSS ≤5, subjects with mRS ≥3 showed a lower MMSE score than those with mRS <3 (p < 0.001). All patients with NIHSS ≤5 but with mRS ≥3 presented either with gait disturbances or MMSE score <25. CONCLUSIONS: The present results suggest that the NIHSS cannot reflect the extent of neurological deficit and clinical severity in subjects with lacunar infarctions in the context of a chronic and diffuse small vessel disease. A specific and global neurological scale, including the assessment of cognitive and gait performances, should be developed for ischemic cerebral microangiopathy. The clinical course of a 60-year-old gentleman with a history of atypical migraine, recurrent encephalopathic episodes and progressive cognitive impairment is presented. He was diagnosed with cerebral autosomal domit arteriopathy with subcortical infarcts and leucoencephalopathy, a rare genetic disorder of the cerebral blood vessels caused by mutations in the Notch 3 gene on chromosome 19. The diagnosis was confirmed by MRI, skin biopsy and genetic testing. His cognitive function has progressively deteriorated and he continues to receive supportive care provision. The course and review of the condition are highlighted. INTRODUCTION: White matter lesions seen on MR scan reflect small vessel disease of the brain; increasing age and high blood pressure are the main risk factors. In young patients without vascular risk factors, screening for CADASIL mutation has to be done. Our aim was to describe clinical as well as radiological features of a series of patients without NOTCH3 mutation with severe vascular leukoencephalopathy not explained by the presence of vascular risk factors. MATERIAL AND METHODS: Inclusion criteria were grade 3 leukoencephalopathy according to the Fazekas scale, age<70years at onset, and negative screening for NOTCH3 gene. Patients with severe vascular risk factors or atherosclerosis were excluded. Clinical and MRI findings were analysed. RESULTS: Eight patients (four men) were included, five did not have any vascular risk factor. Mean age at onset was 59.5years. Initial symptoms were progressive in six cases of eight cases. They consisted of astasia-abasia and progressively worsened; of note one patient died 4years after disease onset. Cerebral MRI disclosed marked atrophy in five patients out of eight, temporal lobe (two out of eight) and external capsule (five out of eight) involvement was moderate. Four patients did not have any other atherosclerosis lesion. Seven out of eight had no retinal microangiopathy. High blood pressure was identified in two patients. CONCLUSION: The identification of vascular leukoencephalopathy in young patients without any vascular risk factors should lead the clinician to perform a complete work-up to search for treatable conditions including high blood pressure. Patients with vascular leukoencephalopathy usually present with astasia-abasia. In this context, cerebral MRI, cannot perfectly discriminate between patients with CADASIL from those with acquired small-vessel disease of the brain so that sequencing of NOTCH3 gene exons 2-24 is recommended. BACKGROUND AND PURPOSE: To describe parkinsonism as a clinical manifestation of cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy. METHODS: We report 5 patients carrying the R1006C mutation in the exon 19 of NOTCH3 gene. All cases presented late onset, slowly progressive parkinsonism, not responsive to l-dopa. We performed brain MRI and (123)I-FP-CIT SPECT in all and in 3 additional patients carrying the same mutation but without parkinsonism. Four patients with parkinsonism underwent myocardial (123)I-meta-iodobenzylguanidine scintigraphy. RESULTS: In all patients, brain MRI showed widespread ischemic lesions in the periventricular white matter, the internal and external capsules, the basal ganglia, and thalami. (123)I-FP-CIT SPECT showed symmetrical or asymmetrical reduction of tracer uptake in the putamen, with inconstant caudate involvement. Myocardial (123)I-meta-iodobenzylguanidine scintigraphy resulted normal. Nigrostriatal denervation was also demonstrated in 2 patients without parkinsonism. CONCLUSIONS: In cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy, parkinsonism may be a not rare, late onset manifestation. The clinical picture, the lack of response to dopaminergic treatment, and MRI findings suggest a vascular parkinsonism, which may be preceded by a protracted presymptomatic phase. BACKGROUND: Cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a disease caused by alterations in the NOTCH3 gene. METHODS: We describe the clinical, instrumental, and genetic findings in CADASIL patients who carry novel NOTCH3 gene mutations. RESULTS AND CONCLUSIONS: This study broadens the spectrum of clinical manifestations and genetic alterations associated with this disease. Some missense mutations and small deletions in the NOTCH3 gene, not involving cysteine residues, have been described in patients considered to be affected by paucisymptomatic CADASIL. However, the significance of such molecular variants is still unclear. We describe a 49-year-old woman with a CADASIL-like phenotype, carrying a novel cysteine-sparing mutation in exon 29 of the NOTCH3 gene, and discuss the possible pathogenetic role of this molecular variant. Even though atypical clinical and MRI findings make a diagnosis of CADASIL unlikely in this patient, our report nevertheless underlines the intriguing genotype-phenotype relationship in NOTCH3 mutations and the importance of functional investigation to ascertain the role of new NOTCH3 mutations in CADASIL pathogenesis. BACKGROUND: Mutations in the TREX1 and NOTCH3 genes cause retinal vasculopathy with cerebral leukodystrophy (RVCL) and cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), respectively. Both are hereditary small vessel diseases of the brain (HSVDB). METHODS: We performed mutational analyses of TREX1 in genomic DNA from 39 unrelated patients who were NOTCH3-negative in genetic testing, selected out of 72 unrelated consecutive patients with HSVDB. RESULTS: Only one patient had a TREX1 sequence variation, a heterozygous TREX1 c.294dupA, putatively resulting in a truncated protein, p.C99MfsX3. The medical history of the patient's family was scrutinized, which revealed that heterozygous TREX1 p.C99MfsX3 was not segregating with the HSVDB. Re-examination of the NOTCH3 sequence data of the proband led to the identification of a homozygous NOTCH3 c.1630C>T (p.R544C) mutation, which segregated with the HSVDB in the family. The proband had a slightly more severe phenotype in comparison with her heterozygous p.R544C sister. CONCLUSION: TREX1 mutation is not a common cause of HSVDB. TREX1 p.C99MfsX3 is not a domit mutation. Homozygosity of the NOTCH3 p.R544C has a modestly deleterious effect on the CADASIL phenotype. The NOTCH3 mutation may cause CADASIL through a gain-of-toxic function effect, which can be modified by other genetic or environmental factors and results in the phenotypic variation of CADASIL. BACKGROUND: Cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebral small vessel disease, clinically characterized by migraine, recurrent transient ischemic attacks or strokes, psychiatric disorders and cognitive decline. Strokes are typically ischemic, while hemorrhagic events have been only sporadically described. However, cerebral microbleeds have been found in 31-69% of CADASIL patients. METHODS: We describe four unrelated CADASIL patients who had hemorrhagic strokes. We also briefly review the literature on intracerebral hemorrhage (ICH) in CADASIL. RESULTS: Three patients had a thalamo-capsular hemorrhage (age at onset: 54, 67, 77) and one of these had a second hemispheric cerebellar hemorrhage. Another patient experienced an interpeduncular cistern subarachnoid hemorrhage when he was 39. None of these patients was receiving antiplatelets, anticoagulants or statins at the time of hemorrhage; all were hypertensive. NOTCH3 gene analysis revealed mutations on exons 14, 22 (two patients presenting the same mutation), and 24. MRI signs of previous hemorrhages were present in all these patients. CONCLUSIONS: Hemorrhagic stroke can occur in CADASIL similarly to sporadic cerebral small vessel diseases; this finding expands the phenotype of the disease. A diagnosis of CADASIL should probably be considered also in patients with ICH. These data bear potential implications in terms of need of better control of risk factors, particularly hypertension, and raise relevant questions about the use of antiplatelets as prevention measures in CADASIL patients. Cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy, or CADASIL, one of the most common inherited small vessel diseases of the brain, is characterized by a progressive loss of vascular smooth muscle cells and extracellular matrix accumulation. The disease is caused by highly stereotyped mutations within the extracellular domain of the NOTCH3 receptor (Notch3(ECD)) that result in an odd number of cysteine residues. While CADASIL-associated NOTCH3 mutations differentially affect NOTCH3 receptor function and activity, they all are associated with early accumulation of Notch3(ECD)-containing aggregates in small vessels. We still lack mechanistic explanation to link NOTCH3 mutations with small vessel pathology. Herein, we hypothesized that excess Notch3(ECD) could recruit and sequester functionally important proteins within small vessels of the brain. We performed biochemical, o-liquid chromatography-tandem mass spectrometry and immunohistochemical analyses, using cerebral and arterial tissue derived from patients with CADASIL and mouse models of CADASIL that exhibit vascular lesions in the end- and early-stage of the disease, respectively. Biochemical fractionation of brain and artery samples demonstrated that mutant Notch3(ECD) accumulates in disulphide cross-linked detergent-insoluble aggregates in mice and patients with CADASIL. Further proteomic and immunohistochemical analyses identified two functionally important extracellular matrix proteins, tissue inhibitor of metalloproteinases 3 (TIMP3) and vitronectin (VTN) that are sequestered into Notch3(ECD)-containing aggregates. Using cultured cells, we show that increased levels or aggregation of Notch3 enhances the formation of Notch3(ECD)-TIMP3 complex, promoting TIMP3 recruitment and accumulation. In turn, TIMP3 promotes complex formation including NOTCH3 and VTN. In vivo, brain vessels from mice and patients with CADASIL exhibit elevated levels of both insoluble cross-linked and soluble TIMP3 species. Moreover, reverse zymography assays show a significant elevation of TIMP3 activity in the brain vessels from mice and patients with CADASIL. Collectively, our findings lend support to a Notch3(ECD) cascade hypothesis in CADASIL disease pathology, which posits that aggregation/accumulation of Notch3(ECD) in the brain vessels is a central event, promoting the abnormal recruitment of functionally important extracellular matrix proteins that may ultimately cause multifactorial toxicity. Specifically, our results suggest a dysregulation of TIMP3 activity, which could contribute to mutant Notch3(ECD) toxicity by impairing extracellular matrix homeostasis in small vessels. BACKGROUND AND PURPOSE: Cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by NOTCH3 gene mutations that result in vascular smooth muscle cell (VSMC) degeneration. Its distinctive feature by electron microscopy (EM) is granular osmiophilic material (GOM) detected in VSMC indentations and/or the extracellular space close to VSMCs. Reports of the sensitivity of EM in detecting GOM in biopsies from CADASIL patients are contradictory. We present data from 32 patients clinically suspected to have CADASIL and discuss the role of EM in its diagnosis in this retrospective study. METHODS: Skin, skeletal muscle, kidney and pericardial biopsies were examined by EM; the NOTCH3 gene was screened for mutations. Skin and muscle biopsies from 12 patients without neurological symptoms served as controls. RESULTS AND DISCUSSION: All GOM-positive patients exhibited NOTCH3 mutations and vice versa. This study i) confirms that EM is highly specific and sensitive for CADASIL diagnosis; ii) extends our knowledge of GOM distribution in tissues where it has never been described, e.g. pericardium; iii) documents a novel NOTCH3 mutation in exon 3; and iv) shows that EM analysis is critical to highlight the need for comprehensive NOTCH3 analysis. Our findings also confirm the genetic heterogeneity of CADASIL in a small Italian subpopulation and emphasize the difficulties in designing algorithms for molecular diagnosis. The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal domit arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P = 0.36) or in controls (rho -0.15, P = 0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL. BACKGROUND AND PURPOSE: CADASIL is the most frequent hereditary small-vessel disease of the brain. The clinical impact of various MR imaging markers has been repeatedly studied in this disorder, but alterations of contrast between gray matter and normal-appearing white matter remain unknown. The aim of this study was to evaluate the contrast alterations between gray matter and normal-appearing white matter on T1-weighted images in patients with CADASIL compared with healthy subjects. MATERIALS AND METHODS: Contrast between gray matter and normal-appearing white matter was assessed by using histogram analyses of 3D T1 high-resolution MR imaging in 23 patients with CADASIL at the initial stage of the disease (Mini-Mental State Examination score > 24 and modified Rankin scale score ≤ 1; mean age, 53.5 ± 11.1 years) and 30 age- and sex-matched controls. RESULTS: T1 contrast between gray matter and normal-appearing white matter was significantly reduced in patients compared with age- and sex-matched controls (patients: 1.35 ± 0.08 versus controls: 1.43 ± 0.04, P < 10(-5)). This reduction was mainly driven by a signal decrease in normal-appearing white matter. Contrast loss was strongly related to the volume of white matter hyperintensities. CONCLUSIONS: Conventional 3D T1 imaging shows significant loss of contrast between gray matter and normal-appearing white matter in CADASIL. This probably reflects tissue changes in normal-appearing white matter outside signal abnormalities on T2 or FLAIR sequences. These contrast alterations should be taken into account for image interpretation and postprocessing. OBJECTIVE: To investigate childhood experiences and psychological characteristics in offspring of a parent with genetic disease. METHOD: Self-report scales were used to assess adverse childhood experiences (ACEs), adult attachment style, mental health, and psychological symptomatology in offspring of a parent with a neurogenetic disorder (i.e. Huntington's Disease, HD; Cerebral Autosomal Domit Arteriopathy with Subcortical Infarcts and Leukoencephalopathy, CADASIL; and Hereditary Cerebral Hemorrhage With Amyloidosis-Dutch type, HCHWA-D), and in offspring of a parent affected with Hereditary Breast/Ovarian Cancer (HBOC). These groups were compared to persons who did not have a parent with one of these genetic diseases. Associations between childhood experiences and adult psychological characteristics were investigated. RESULTS: Compared with the reference group (n = 127), offspring of a parent with a neurogenetic disorder (n = 96) reported more parental dysfunction in childhood, and showed more adult attachment anxiety and poorer mental health. Offspring of a parent with HBOC (n = 70) reported more parental loss in childhood and showed poorer mental health. Offspring who experienced parental genetic disease in childhood had more attachment anxiety than offspring who experienced parental disease later in life. In the group of offspring, a higher number of ACEs was associated with poorer mental health and more psychological symptomatology. CONCLUSIONS: This cross-sectional study indicates that adult offspring of a parent with genetic disease may differ in attachment style and mental health from persons without one of these genetic diseases in their family, and that this may be related to adverse childhood experiences.

Which neuroendocrine tumors are associated with specific tumor syndromes?

Neuroendocrine tumors are a heterogeneous group of benign and malignant neoplasias, detectable in the context of hereditary tumor syndromes in up to 30% of cases. Neuroendocrine tumors include medullary thyroid carcinoma, gastroenteropancreatic tumors, pheochromocytoma, and paraganglioma.

Neuroendocrine tumors (NETs) are a heterogeneous group of benign and maligt neoplasias, detectable in the context of hereditary tumor syndromes in up to 30% of cases. The pathogenic understanding of NETs has increased considerably during the last decade, mainly due to the identification of underlying genetic defects and the availability of genetically modified animal models. These developments are reflected in a revised WHO classification of gastrointestinal NETs. In contrast to a variety of rare neuroendocrine tumor syndromes, multiple endocrine neoplasia syndrome type 1 (MEN1) and type 2 (MEN2) play clinically significant roles due to their common incidence. MEN1 and MEN2 are classic autosomal-domit familial tumor diseases with a high penetrance and variable clinical expression, caused by germ line mutations of the MEN1 tumor suppressor gene and the RET protooncogene, respectively. The clinical management of patients with NETs has changed significantly after the introduction of clinical genetic screening. The detection of MEN1 mutations allows for risk-adapted treatment and follow-up. RET gene analysis can identify individuals with a very high risk to develop familial medullary cancer (MEN2), who may be successfully treated by prophylactic thyroidectomy. NETs thus represent a paradigmatic example of the successful link between basic genetic science and clinical care in molecular medicine. Endocrine and neuroendocrine cells form a large and diverse array of cell types. They are present in the form of specialized organs, such as the pituitary, parathyroid, thyroid, and adrenal gland, or in the form of the diffuse neuroendocrine system in the respiratory and digestive tracts. Neuroendocrine tumors are a heterogeneous group of neoplasms, yet they present certain unifying features. These include frequent hormonal overproduction that leads to specific symptoms and a typical immunohistochemical staining profile with chromogranin A and synaptophysin reactivity. Over the past decades, many neuroendocrine tumors have been described in the context of heritable tumor syndromes, and there exist several syndromes that are almost entirely composed of neuroendocrine tumors. Tumors occurring as part of these hereditary syndromes are characterized by specific genetic abnormalities that have helped our understanding of tumorigenesis, and they frequently appear at a young age. It is therefore important for the pediatric pathologist to be aware of specific histologic characteristics of neuroendocrine tumors in childhood and of their association with specific tumor syndromes. This may alert other clinicians to the possibility of multiple tumors in the patient or his family members. This review focuses on hereditary syndromes with neuroendocrine tumors, including multiple endocrine neoplasia types 1 and 2, Von Hippel-Lindau disease, neurofibromatosis type 1, Carney complex, pheochromocytoma-paraganglioma syndrome, and familial nonmedullary thyroid carcinoma. In addition, several individual neuroendocrine tumors are described, such as medullary thyroid carcinoma, gastroenteropancreatic tumors, pheochromocytoma, and paraganglioma, emphasizing specific histopathologic characteristics. BACKGROUND: Pancreatic neuroendocrine tumors (PNETs) are a characteristic feature of the tumor syndromes multiple endocrine neoplasia type 1 (MEN-1) and von Hippel-Lindau disease (VHL). With VHL, about 10% of the patients exhibit PNETs by age 40 years. Metastatic potential is high if the tumors have grown to >3 cm in diameter. Optimal surgical treatment is still a challenge. METHODS: We report three cases, all women, ages 22, 30, and 39 years, respectively, who had known VHL, confirmed by classic organ manifestations and germline mutations of the VHL gene. All were diagnosed, in an asymptomatic stage, with solid tumors of the pancreatic tail or tail/corpus area measuring 2.9-5.6 cm diameter. All accepted the offer of laparoscopic organ-sparing removal of the tumors. RESULTS: In all three cases, the tumor was entirely removed. In two cases, resection of the spleen was also necessary as dissection of the tumor from the major splenic vessels was impossible. Operating time was 215-365 min, and blood loss was 200-700 ml. Histolopathology revealed benign PNETs in two cases, but the third patient had regional lymph node metastases. There were no complications, and the hospital stay was 4-7 days. CONCLUSIONS: Organ-sparing laparoscopic surgery is an important option for treating VHL-associated PNETs of the pancreatic tail. Pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare neuroendocrine tumors of the adrenal glands and the sympathetic and parasympathetic paraganglia. They can occur sporadically or as a part of different hereditary tumor syndromes. About 30% of PCCs and PGLs are currently believed to be caused by germline mutations and several novel susceptibility genes have recently been discovered. The clinical presentation, including localization, maligt potential, and age of onset, varies depending on the genetic background of the tumors. By reviewing more than 1700 reported cases of hereditary PCC and PGL, a thorough summary of the genetics and clinical features of these tumors is given, both as part of the classical syndromes such as multiple endocrine neoplasia type 2 (MEN2), von Hippel-Lindau disease, neurofibromatosis type 1, and succinate dehydrogenase-related PCC-PGL and within syndromes associated with a smaller fraction of PCCs/PGLs, such as Carney triad, Carney-Stratakis syndrome, and MEN1. The review also covers the most recently discovered susceptibility genes including KIF1Bβ, EGLN1/PHD2, SDHAF2, TMEM127, SDHA, and MAX, as well as a comparison with the sporadic form. Further, the latest advances in elucidating the cellular pathways involved in PCC and PGL development are discussed in detail. Finally, an algorithm for genetic testing in patients with PCC and PGL is proposed. Pheochromocytomas are neuroendocrine tumors of the adrenal medulla which can occur either sporadically or in the context of hereditary tumor syndromes. Whereas the genetic background of hereditary pheochromocytomas is becoming rather well-defined, very little is known about the more common sporadic form of the disease which constitutes ∼70% of all cases. In this study, we elucidate some of the molecular mechanisms behind sporadic pheochromocytoma by performing a comprehensive analysis of copy number alterations, gene expression, promoter methylation and somatic mutations in the genes RET, VHL, NF1, SDHA, SDHB, SDHC, SDHD, SDHAF2, KIF1Bβ, TMEM127 and MAX, which have been associated with hereditary pheochromocytoma or paraganglioma. Our genomic and genetic analyses of 42 sporadic pheochromocytomas reveal that a large proportion (83%) has an altered copy number in at least one of the known susceptibility genes, often in association with an altered messenger RNA (mRNA) expression. Specifically, 11 sporadic tumors (26%) displayed a loss of one allele of the NF1 gene, which significantly correlated with a reduced NF1 mRNA expression. Subsequent sequencing of NF1 mRNA, followed by confirmation in the corresponding genomic DNA (gDNA), revealed somatic truncating mutations in 10 of the 11 tumors with NF1 loss. Our results thus suggest that the NF1 gene constitutes the most frequent (24%) target of somatic mutations so far known in sporadic pheochromocytomas.

How many periods of regulatory innovation led to the evolution of vertebrates?

Investigators proposed that there have been three extended periods in the evolution of gene regulatory elements. Early vertebrate evolution was characterized by regulatory gains near transcription factors and developmental genes, but this trend was replaced by innovations near extracellular signaling genes, and then innovations near posttranslational protein modifiers.

Is nintedanib effective for Idiopathic Pulmonary Fibrosis?

Yes, nintedanib is approved for Idiopathic Pulmonary Fibrosis treatment. Nintedanib was shown to slow the decline in lung function, decrease acute exacerbations, decrease the annual rate of decline in forced vital capacity and increase time to acute exacerbation.

The tyrosine kinase inhibitor nintedanib (BIBF 1120) is in clinical development for the treatment of idiopathic pulmonary fibrosis. To explore its mode of action, nintedanib was tested in human lung fibroblasts and mouse models of lung fibrosis. Human lung fibroblasts expressing platelet-derived growth factor (PDGF) receptor-α and -β were stimulated with platelet-derived growth factor BB (homodimer) (PDGF-BB). Receptor activation was assessed by autophosphorylation and cell proliferation by bromodeoxyuridine incorporation. Transforming growth factor β (TGFβ)-induced fibroblast to myofibroblast transformation was determined by α-smooth muscle actin (αSMA) mRNA analysis. Lung fibrosis was induced in mice by intratracheal bleomycin or silica particle administration. Nintedanib was administered every day by gavage at 30, 60, or 100 mg/kg. Preventive nintedanib treatment regimen started on the day that bleomycin was administered. Therapeutic treatment regimen started at various times after the induction of lung fibrosis. Bleomycin caused increased macrophages and lymphocytes in the bronchoalveolar lavage (BAL) and elevated interleukin-1β (IL-1β), tissue inhibitor of metalloproteinase-1 (TIMP-1), and collagen in lung tissue. Histology revealed chronic inflammation and fibrosis. Silica-induced lung pathology additionally showed elevated BAL neutrophils, keratinocyte chemoattractant (KC) levels, and granuloma formation. Nintedanib inhibited PDGF receptor activation, fibroblast proliferation, and fibroblast to myofibroblast transformation. Nintedanib significantly reduced BAL lymphocytes and neutrophils but not macrophages. Furthermore, interleukin-1β, KC, TIMP-1, and lung collagen were significantly reduced. Histologic analysis showed significantly diminished lung inflammation, granuloma formation, and fibrosis. The therapeutic effect was dependent on treatment start and duration. Nintedanib inhibited receptor tyrosine kinase activation and the proliferation and transformation of human lung fibroblasts and showed antifibrotic and anti-inflammatory activity in two animal models of pulmonary fibrosis. These results suggest that nintedanib may impact the progressive course of fibrotic lung diseases such as idiopathic pulmonary fibrosis. Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic lung disease with no clear etiology and few therapeutic options. Growth factors that act as mediators in the development of this disease might be important therapeutic targets. Nintedanib is a triple-tyrosine kinase inhibitor and a potent antagonist of growth factors such as platelet-derived growth factor, vascular endothelial growth factor, and basic fibroblast growth factor, and it is currently evaluated in clinical trials as a potential IPF therapy. Treatment with nintedanib may slow decline in lung function, decrease the frequency of exacerbations, and improve quality of life in subjects with IPF. This observation, together with extensive safety and pharmacokinetic data from studies of nintedanib in maligcy, led the way for the clinical development of this drug in IPF. Observations from clinical trials, together with the preclinical data, suggest that nintedanib may become an important therapeutic option for individuals with IPF. High-dose nintedanib improved the quality of life, slowed the progression of lung fibrosis and the decline of lung function, and reduced the rate of exacerbations in individuals with mild and moderate IPF. This is a short review based on the available data (September 2013) on nintedanib. BACKGROUND: Nintedanib is in clinical development as a treatment for idiopathic pulmonary fibrosis (IPF). Data from the Phase II TOMORROW study suggested that nintedanib 150 mg twice daily had clinical benefits with an acceptable safety profile. METHODS: The INPULSIS™ trials are replicate Phase III, randomized, double-blind, studies comparing the efficacy and safety of nintedanib 150 mg twice daily with placebo in patients with IPF. Eligible patients were aged ≥40 years with a diagnosis of IPF within 5 years before randomization who had undergone a chest high-resolution computed tomography (HRCT) scan within 1-year before screening, and who had a forced vital capacity (FVC) of ≥50% predicted and a diffusing capacity for carbon monoxide of 30-79% predicted. Participants were randomized 3:2 to receive nintedanib or placebo for 52 weeks. The primary endpoint is the annual rate of decline in FVC. The key secondary endpoints are change from baseline in the total score on the St. George's Respiratory Questionnaire (a measure of health-related quality of life) over 52 weeks and time to first acute exacerbation. RESULTS: Enrolment of 1066 patients in 24 countries was completed in September 2012. Results will be reported in the first half of 2014. CONCLUSION: The INPULSIS™ trials will determine the efficacy of nintedanib in patients with IPF, including its impact on disease progression as defined by decline in FVC, acute exacerbations and health-related quality of life. In addition, they will characterise the adverse event profile of nintedanib in this patient population. TRIAL REGISTRATION: Registered at ClinicalTrials.gov (identifiers: NCT01335464 and NCT01335477). Collaborators: Corte T, Davies H, Glaspole I, Mulder J, Veitch E, De Vuyst P, Liistro G, Sibille Y, Vincken W, Wuyts W, Fell C, Herdez P, Kolb M, Undurraga A, Bai C, Chen P, Gao Z, Kang J, Li H, Li Z, Wan H, Wang H, Wen F, Xiao Q, Xu Z, Zhang W, Zheng X, Zhu H, Pauk N, Reiterer P, Vasakova M, Hodgson U, Bourdin A, Cadranel J, Camus P, Chanez P, Cottin V, Crestani B, Israel-Biet D, Jouneau S, Lebargy F, Marquette C, Prévot G, Valeyre D, Wallaert B, Bonnet R, Costabel U, Gläser S, Grohé C, Guenther A, Hammerl P, Höffken G, Karagiannidis C, Kirschner J, Kirsten A, Korn S, Kreuter M, Müller-Quernheim J, Neurohr C, Pfeifer M, Schönfeld N, Wiewrodt R, Antoniou K, Daniil Z, Diamantea F, Koulouris N, Mathioudakis G, Ghosal A, Kadappa Shivappa S, Kawedia M, Khatavkar P, Kumar A, Mehta P, Singh V, Srikanth K, Thakker H, Udwadia Z, Egan J, Fink G, Kramer M, Yigla M, Agostini C, De Benedetto F, Harari S, Luppi F, Paggiaro P, Tavanti L, Pesci A, Poletti V, Rottoli P, Saltini C, Sanduzzi Zamparelli A, Vancheri C, Bando M, Hasegawa Y, Hashimoto K, Homma S, Inase N, Inoue Y, Arai T, Izumi S, Kawamura T, Kishi K, Kondo Y, Kuwano K, Miura Y, Nishioka Y, Nishiyama O, Ogura T, Ohkouchi S, Saito T, Setoguchi Y, Shindoh J, Taguchi Y, Tanakadate M, Tomii K, Sugita Y, Yamaguchi T, Yoshimori K, Jeong S, Kim D, Kim Y, Park C, Song J, Uh S, Selman M, Bresser P, Grutters J, Wijsenbeek M, Arrobas A, Cardoso J, Costa R, Morais A, Neves S, Serrado M, Ilkovick M, Vizel A, Alfageme Michavila I, Ancochea J, Castillo Villegas D, Molina-Molina M, Morell F, Xaubet A, Aktogu Ozkan S, Kayacan O, Ongen G, Mogulkoc N, Tuncay E, Beirne P, Bettinson H, Burge P, Dempsey O, Maher T, Millar A, Spencer L, Thickett D, Alvarez J, Andrews C, Bajwa O, Baker A, Baughman R, Belperio J, Bradley J, Collard H, Cordova F, Daniels C, de Andrade J, Dushay K, Enelow R, Ettinger N, Gibson K, Gotfried M, Hajari Case A, Hotchkin D, Huggins J, Kaye M, Kershaw C, Kureishy S, Lancaster L, Lederer D, Mageto Y, Masson J, Meyer K, Mohabir P, Morrison L, Nathan S, Noth I, Oelberg D, Rahaghi F, Riley D, Rizzo A, Rossman M, Ruzi J, Sachs P, Schaumberg T, Scholand M, Schroeder C, Seifer F, Shea J, Sinkowitz D, Tabak J, Taylor J, Thompson J, Thurm C, Tita J, Wencel M, Westerman J, Lasky J, Demedts M, Casteels M, Loddenkemper R, Michaelis J, Lasky J, Demedts M, Roman J, Tino G, Luisetti M. Nintedanib (Ofev(®)) is an orally available, small, multiple receptor tyrosine kinase inhibitor developed by Boehringer Ingelheim for the treatment of idiopathic pulmonary fibrosis (IPF) and cancer. Nintedanib received its first global approval in the US in October 2014 for the treatment of IPF. Nintedanib has received a positive opinion from the European Medicines Agency's Committee for Medicinal Products for Human Use for the treatment of IPF, and for the second-line treatment in combination with docetaxel of locally advanced, metastatic or locally recurrent non-small cell lung cancer of adenocarcinoma tumour histology. Phase 3 development programmes are also underway for colorectal cancer and ovarian cancer. Phase 2 investigation is being conducted for a variety of other solid tumours, including hepatocellular carcinoma, mesothelioma, prostate cancer, glioblastoma, renal cell carcinoma and endometrial cancer. This article summarizes the milestones in the development of nintedanib leading to this first approval for IPF. Author information: (1)Department of Respiratory Medicine, Unit for Interstitial Lung Diseases, University Hospitals Leuven, Leuven, Belgium. (2)Department of Thoracic Medicine and Laboratory of Cellular and Molecular Pneumonology, Medical School, University of Crete, Crete, Greece. (3)Inserm U1152, Université Paris Diderot, PRES Sorbonne Paris Cité, LabEx Inflamex, and Assistance Publique-Hôpitaux de Paris, DHU FIRE, Paris, France; Service de Pneumologie A, Centre de Compétence des Maladies Pulmonaires Rares, Hôpital Bichat, Paris, France. (4)Department of Pneumology/Allergology, Ruhrlandklinik, University Hospital, University Duisburg-Essen, Essen, Germany. (5)Hôpital Louis Pradel, Claude Bernard Lyon 1 University, Lyon, France. (6)Centre for Interstitial Lung Diseases and University Medical Center Utrecht, Department of Pulmonology, St. Antonius Hospital Nieuwegein, Netherlands. (7)NIHR Biological Research Unit, Royal Brompton Hospital, Sydney Street, London, UK. (8)Department of Diseases of the Thorax, Ospedale GB Morgagni, Forlì, Italy. (9)National Institute for Health Research, Southampton Respiratory Biomedical Research Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK. (10)Regional Centre for Interstitial and Rare Lung Diseases, Department of Clinical and Molecular Biomedicine, University of Catania, Catania, Italy. (11)Interstitial Lung Disease Unit, Royal Brompton Hospital, London, UK. Electronic address: [email protected]. Meningococcal group B vaccine (Trumenba) to prevent more types of invasive meningococcal disease; antihemophilic factor (recombit), porcine sequence (Obizur) to treat bleeding from acquired hemophilia A; and pirfenidone (Esbriet) and nintedanib (Ofev) for idiopathic pulmonary fibrosis. The period covered by this update can be considered as the most exciting period in idiopathic pulmonary fibrosis (IPF) research. It started with the identification of genetic variants that are associated with IPF in the majority of patients and continued with discovery of molecular and genetic biomarkers that predict distinct clinical presentations of patients with IPF and potential new biological mechanisms. More importantly, the period ends with the publication of two groundbreaking studies that confirmed that two drugs, pirfenidone and nintedanib, slowed disease progression, leading to a historic approval by the FDA. In this update, we describe these key advances, their scientific and significant clinical implications, and future directions. Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive diffuse parenchymal lung disease of unknown origin, with a mortality rate exceeding that of many cancers. The diagnostic process is complex and relies on the clinician integrating clinical, laboratory, radiological, and histological data. In the last decade, major advances in our understanding of the pathogenesis of IPF have shifted the paradigm from a primarily inflammatory process evolving to fibrosis to a condition driven by aberrant wound healing following alveolar epithelial cell injury that results in scarring of the lung, architectural distortion, and irreversible loss of function. Improved understanding of disease pathogenesis has led to the identification of several therapeutic targets and the design of high-quality clinical trials evaluating novel compounds. However, the results of these studies have been mostly disappointing, probably due to the plethora of mediators, growth factors, and signaling pathways involved in the fibrotic process. Most recently, pirfenidone and nintedanib, two compounds with pleiotropic anti-fibrotic properties, have been proven effective in reducing functional decline and disease progression in IPF. This is a major breakthrough. Nevertheless, we still have a long way to go. In fact, neither pirfenidone nor nintedanib is a cure for IPF, and most patients continue to progress despite treatment. As such, comprehensive care of patients with IPF, including management of concomitant conditions and physical debility, as well as timely referral for lung transplantation, remains essential. Several agents with a high potential are currently being tested, and many more are ready for clinical trials. Their completion is critical for achieving the ultimate goal of curing patients with IPF. RATIONALE: Increased abundance and stiffness of the extracellular matrix, in particular collagens, is a hallmark of idiopathic pulmonary fibrosis (IPF). FK506-binding protein 10 (FKBP10) is a collagen chaperone, mutations of which have been indicated in the reduction of extracellular matrix stiffness (e.g., in osteogenesis imperfecta). OBJECTIVES: To assess the expression and function of FKBP10 in IPF. METHODS: We assessed FKBP10 expression in bleomycin-induced lung fibrosis (using quantitative reverse transcriptase-polymerase chain reaction, Western blot, and immunofluorescence), analyzed microarray data from 99 patients with IPF and 43 control subjects from a U.S. cohort, and performed Western blot analysis from 6 patients with IPF and 5 control subjects from a German cohort. Subcellular localization of FKBP10 was assessed by immunofluorescent stainings. The expression and function of FKBP10, as well as its regulation by endoplasmic reticulum stress or transforming growth factor-β1, was analyzed by small interfering RNA-mediated loss-of-function experiments, quantitative reverse transcriptase-polymerase chain reaction, Western blot, and quantification of secreted collagens in the lung and in primary human lung fibroblasts (phLF). Effects on collagen secretion were compared with those of the drugs nintedanib and pirfenidone, recently approved for IPF. MEASUREMENTS AND MAIN RESULTS: FKBP10 expression was up-regulated in bleomycin-induced lung fibrosis and IPF. Immunofluorescent stainings demonstrated localization to interstitial (myo)fibroblasts and CD68(+) macrophages. Transforming growth factor-β1, but not endoplasmic reticulum stress, induced FKBP10 expression in phLF. The small interfering RNA-mediated knockdown of FKBP10 attenuated expression of profibrotic mediators and effectors, including collagens I and V and α-smooth muscle actin, on the transcript and protein level. Importantly, loss of FKBP10 expression significantly suppressed collagen secretion by phLF. CONCLUSIONS: FKBP10 might be a novel drug target for IPF. Idiopathic pulmonary fibrosis (IPF) conveys a median survival of 3 years and until recently has lacked effective therapies. Nintedanib, an orally available, small-molecule tyrosine kinase inhibitor with selectivity for vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) receptors has recently been shown, in two pivotal phase III studies, to effectively slow IPF disease progression. Consequently, nintedanib was given accelerated approval by the FDA in October 2014 for the treatment of IPF. This monograph explores the preclinical rationale for the antifibrotic role of nintedanib and provides an overview of the available data on pharmacokinetics, efficacy and safety. Idiopathic pulmonary fibrosis (IPF) is a progressive disease with poor prognosis. The molecular mechanisms involved in the progression of IPF are not fully understood; however, the platelet-derived growth factor (PDGF)/PDGF receptor pathway is thought to play a critical role in fibrogenesis of the lungs. Other growth factors, including fibroblast growth factor and vascular endothelial growth factor, are also thought to contribute to the pathogenesis of pulmonary fibrosis. Nintedanib is an inhibitor of multiple tyrosine kinases, including receptors for PDGF, fibroblast growth factor, and vascular endothelial growth factor. In the Phase II TOMORROW trial, treatment with 150 mg of nintedanib twice daily showed a trend to slow the decline in lung function and significantly decrease acute exacerbations in patients with IPF, while showing an acceptable safety profile. The Phase III INPULSIS trials demonstrated a significant decrease in the annual rate of decline in forced vital capacity in IPF patients treated with 150 mg nintedanib twice daily. In the INPULSIS-2 trial, the time to the first acute exacerbation significantly increased in IPF patients who were treated with 150 mg of nintedanib twice daily. Pirfenidone, another antifibrotic drug, was shown to limit the decline in pulmonary function in patients with IPF in the ASCEND trial. Combination therapy with nintedanib and pirfenidone is anticipated, although further evaluation of its long-term safety is needed. There is limited evidence for the safety of the combination therapy although a Phase II trial conducted in Japan demonstrated that combination therapy with nintedanib and pirfenidone was tolerable for 1 month. Available antifibrotic agents (ie, pirfenidone and N-acetylcysteine) have limited efficacy as single therapies for IPF; therefore, further study of combination therapy with antifibrotic agents is needed. Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease of unknown cause. The clinical course is unpredictable, but the disease is usually progressive with a median survival of 2-5 years as a result of advanced respiratory failure. The current hypothesis of the disease mechanism is recurrent injury to the respiratory epithelium which leads to an uncontrolled wound healing process resulting in fibrosis rather than repair. Despite better understanding of the pathogenesis, there is no effective therapy for the disease. In this review, we present the positive results of recently published clinical trials regarding therapy for IPF, with emphasis on pirfenidone and nintedanib.

What is the role of SERCA in diabetic cardiomyopathy?

Diabetic cardiomyopathy is accompanied by reduced SERCA levels and activity in later stages. The up-regulation of SERCA2a in the early phase of type 2 diabetes is an important physiological adaptation of the heart.

Slowed relaxation in diabetic cardiomyopathy (CM) is partially related to diminished expression of the sarcoplasmic reticulum (SR) Ca2+-ATPase SERCA2a. To evaluate the impact of SERCA2a overexpression on SR Ca2+ handling in diabetic CM, we 1) generated transgenic rats harboring a human cytomegalovirus enhancer/chicken beta-actin promotor-controlled rat SERCA2 transgene (SERCA2-TGR), 2) characterized their SR phenotype, and 3) examined whether transgene expression may rescue SR Ca2+ transport in streptozotocin-induced diabetes. The transgene was expressed in all heart chambers. Compared to wild-type (WT) rats, a heterozygous line exhibited increased SERCA2 mRNA (1.5-fold), SERCA2 protein (+26%) and SR Ca2+ uptake (+37%). Phospholamban expression was not altered. In SERCA2-TGR, contraction amplitude (+48%) and rates of contraction (+34%) and relaxation (+35%) of isolated papillary muscles (PM) were increased (P2+ uptake and SERCA2 protein of SERCA2-TGR were 1.3-fold higher (P2+ uptake, accelerates relaxation and compensates, in part, for depressed Ca2+ uptake in diabetic CM. Therefore, SERCA2 expression might constitute an important therapeutic target to rescue cardiac SR Ca2+ handling in diabetes. Diabetic cardiomyopathy is characterized by impaired ventricular contraction and altered function of insulin-like growth factor I (IGF-I), a key factor for cardiac growth and function. Endogenous IGF-I has been shown to alleviate diabetic cardiomyopathy. This study was designed to evaluate exogenous IGF-I treatment on the development of diabetic cardiomyopathy. Adult rats were divided into four groups: control, control + IGF-I, diabetic, and diabetic + IGF-I. Streptozotocin (STZ; 55 mg/kg) was used to induce experimental diabetes immediately followed by a 7-wk IGF-I (3 mg. kg(-1). day(-1) ip) treatment. Mechanical properties were assessed in ventricular myocytes including peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR(90)) and maximal velocities of shortening/relengthening (+/-dL/dt). Intracellular Ca(2+) transients were evaluated as Ca(2+)-induced Ca(2+) release and Ca(2+) clearing constant. Levels of sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA), phospholamban (PLB), and glucose transporter (GLUT4) were assessed by Western blot. STZ caused significant weight loss and elevated blood glucose, demonstrating the diabetic status. The diabetic state is associated with reduced serum IGF-I levels, which were restored by IGF-I treatment. Diabetic myocytes showed reduced PS and +/-dL/dt as well as prolonged TPS, TR(90), and intracellular Ca(2+) clearing compared with control. IGF-I treatment prevented the diabetes-induced abnormalities in PS, +/-dL/dt, TR(90), and Ca(2+) clearing but not TPS. The levels of SERCA and GLUT4, but not PLB, were significantly reduced in diabetic hearts compared with controls. IGF-I treatment restored the diabetes-induced decline in SERCA, whereas it had no effect on GLUT4 and PLB levels. These results suggest that exogenous IGF-I treatment may ameliorate contractile disturbances in cardiomyocytes from diabetic animals and could provide therapeutic potential in the treatment of diabetic cardiomyopathy. The depressed sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a) and Ca2+-release channels (ryanodine receptor RyR2) are involved in the diabetic cardiomyopathy. However, an implication of a down-regulation of FK506-binding protein or calstabin-2 (FKBP12.6) is undefined. It was hypothesized that the down-regulation of FKBP12.6 and SERCA2a of the intracellular calcium handling system is closely related to an up-regulated endothelin (ET) system. An ET receptor antagonist CPU0213 is newly discovered and expected to ameliorate cardiac insufficiency which is mediated by the depressed FKBP12.6 and SERCA2a in diabetic rat heart. Diabetes was developed in male Sprague-Dawley rats 8 weeks after an injection of streptozotocin (60 mg/kg IP), and CPU0213 was instituted 30 mg/kg, SC in the last 4 weeks. The assessment of the cardiac function, cardiac calcium handling proteins, endothelin system, and redox enzyme system were conducted. The compromised cardiac function in diabetic rats was accompanied by a significant down-regulation of expression of FKBP12.6 as well as SERCA2a and phospholamban. These were closely linked with an increased ET-1 and up-regulation of endothelin converting enzyme, PropreET1, and inducible nitric oxide synthase mRNA in diabetic cardiomyopathy. After 4-week treatment, CPU0213 was capable to attenuate completely the down-regulated FKBP12.6 and SERCA2a, and up-regulated ET system in association with a recovery of the cardiac insufficiency of diabetic cardiomyopathy. OBJECTIVE: Diabetic cardiomyopathy is an increasingly recognized cause of cardiac failure despite preserved left ventricular systolic function. Given the over-expression of angiotensin II in human diabetic cardiomyopathy, we hypothesized that combining hyperglycaemia with an enhanced tissue renin-angiotensin system would lead to the development of diastolic dysfunction with adverse remodeling in a rodent model. METHODS: Homozygous (mRen-2)27 rats and non-transgenic Sprague Dawley (SD) rats were randomized to receive streptozotocin (diabetic) or vehicle (non-diabetic) and followed for 6 weeks. Prior to tissue collection, animals underwent pressure-volume loop acquisition. RESULTS: Diabetic Ren-2 rats developed impairment of both active and passive phases of diastole, accompanied by reductions in SERCA-2a ATPase and phospholamban along with activation of the fetal gene program. Structural features of diabetic cardiomyopathy in the Ren-2 rat included interstitial fibrosis, cardiac myocyte hypertrophy and apoptosis in conjunction with increased activity of transforming growth factor-beta (p<0.01 compared with non-diabetic Ren-2 rats for all parameters). No significant functional or structural derangements were observed in non-transgenic, SD diabetic rats. CONCLUSION: These findings indicate that the combination of enhanced tissue renin-angiotensin system and hyperglycaemia lead to the development of diabetic cardiomyopathy. Fibrosis, and myocyte hypertrophy, a prominent feature of this model, may be a consequence of activation of the pro-sclerotic cytokine, transforming growth factor-beta, by the diabetic state. OBJECTIVE: This study examines the extent to which the contractile deficit of diabetic cardiomyopathy is due to altered Ca(2+) homeostasis. RESEARCH DESIGN AND METHODS: Measurements of isometric force and intracellular calcium ([Ca(2+)](i), using fura-2/AM) were made in left ventricular (LV) trabeculae from rats with streptozotocin-induced diabetes and age-matched siblings. RESULTS: At 1.5 mmol/l [Ca(2+)](o), 37 degrees C, and 5-Hz stimulation frequency, peak stress was depressed in diabetic rats (10 +/- 1 vs. 17 +/- 2 mN/mm(2) in controls; P < 0.05) with a slower time to peak stress (77 +/- 3 vs. 67 +/- 2 ms; P < 0.01) and time to 90% relaxation (76 +/- 7 vs. 56 +/- 3 ms; P < 0.05). No difference was found between groups for either resting or peak Ca(2+), but the Ca(2+) transient was slower in time to peak (39 +/- 2 vs. 34 +/- 1 ms) and decay (time constant, 61 +/- 3 vs. 49 +/- 3 ms). Diabetic rats had a longer LV action potential (APD(50), 98 +/- 5 vs. 62 +/- 5 ms; P < 0.0001). Western blotting showed that diabetic rats had a reduced expression of sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA)2a, with no difference in expression of the Na(+)/Ca(2+) exchanger. Immunohistochemistry of LV free wall showed that type I collagen was increased in diabetic rats (diabetic 7.1 +/- 0.1%, control 12.7 +/- 0.1%; P < 0.01), and F-actin content reduced (diabetic 56.9 +/- 0.6%; control 61.7 +/- 0.4%; P < 0.0001) with a disrupted structure. CONCLUSIONS: We find no evidence to support the idea that altered Ca(2+) homeostasis underlies the contractile deficit of diabetic cardiomyopathy. The slower action potential and reduced SERCA2a expression can explain the slower Ca(2+) transient kinetics in diabetic rats but not the contractile deficit. Instead, we suggest that the observed LV remodeling may play a crucial role. Depressed sarcoplasmic reticulum (SR) Ca(2+)-ATPase (SERCA2a) and Ca(2+)-release channels (ryanodine receptor RyR2) are involved in diabetic cardiomyopathy, however, the implication of intracellular calcium handling proteins in SR is undefined. It was hypothesized that the down-regulation of the intracellular calcium handling proteins of SR is closely related to an up-regulated endothelin (ET) system. Hydroxysafflor yellow A (HSYA) is expected to ameliorate cardiac insufficiency which is mediated by the depressed intracellular calcium handling system in diabetic rat heart. Diabetes was produced in male rats 8 weeks after an injection of streptozotocin (60 mg/kg i.p.) and HSYA was administered (100 mg/kg) by gavage in the last 4 weeks. Hemodynamic and echocardiographic changes, cardiac calcium handling proteins, serum biochemistry, ET system and redox were measured. The compromised cardiac function in diabetic rats was accompanied by a significant down-regulation of the expression of RyR2, FKBP12.6 as well as SERCA2a and PLB. These were closely linked with oxidative stress, an increased ET-1 and up-regulation of ECE, PropreET-1 and iNOS mRNA in diabetic cardiomyopathy. After a 4 week treatment with HSYA, all abnormalities were reversed significantly. In conclusion, diabetic cardiomyopathy was correlated with an abnormal expression of calcium handing proteins in SR and an activated ET-ROS (reactive oxygen species) system in the diabetic affected myocardium. HSYA significantly improved the cardiac function and down-regulated the ET system and ROS pathway, resulting in a reversal of the abnormalities of expression of calcium handing proteins and the cardiac performance in diabetic cardiomyopathy. To investigate the influence of breviscapine on the cardiac structure and function in diabetic cardiomyopathy rats as well as the expression of protein kinase C (PKC) and Ca(2+)-cycling proteins expression. Diabetes was induced in male Sprague-Dawley rats by a single intraperitoneal injection of streptozotocin and the control rats were injected with saline. After the induction of diabetes for 4 weeks, the animals were divided into different groups: (1) normal rats as control; (2) diabetic rats; (3) diabetic rats with administration of breviscapine (10 or 25 mg kg(-1) day(-2)). After treatment with breviscapine for 6 weeks, the invasive cardiac function and echocardiographic parameters were measured, and heart tissue was obtained for electron microscope study. The expression of protein kinase C (PKC) and calcium handling regulators, such as protein phosphatase inhibitor-1 (PPI-1), phospholamban (PLB) and Ca(2+)-ATPase (SERCA-2), ryanodine receptor (RyR) were detected by western blot or RT-PCR. The activity of SERCA-2 was measured using Ca(2+)-ATPase kit. Diabetic rats showed impaired cardiac structure and function compared with control rats. The expression of PKC, PLB increased significantly, while the PPI-1, SERCA-2 and RyR expression decreased. Treatment with breviscapine could reverse the cardiac dysfunction and structure changes in diabetic cardiomyopathy rats, and decrease the expression of PKC and PLB, as well as increase the expression of PPI-1, SERCA-2 and RyR. The protective effect of breviscapine was dose related. This study showed that breviscapine could regulate the expression of PKC, PPI-1, PLB and SERCA-2 and have protective effect on diabetic cardiomyopathy. Reduced sarcoplasmic calcium ATPase (SERCA2a) expression has been shown to play a significant role in the cardiac dysfunction in diabetic cardiomyopathy. The mechanism of SERCA2a repression is, however, not known. This study was designed to examine the effect of resveratrol (RSV), a potent activator of SIRT1, on cardiac function and SERCA2a expression in chronic type 1 diabetes. Adult male mice were injected with streptozotocin (STZ) and fed with either a regular diet or a diet enriched with RSV. STZ administration produced progressive decline in cardiac function, associated with markedly reduced SERCA2a and SIRT1 protein levels and increased collagen deposition; RSV treatment to these mice had a tremendous beneficial effect both in terms of improving SERCA2a expression and on cardiac function. In cultured cardiomyocytes, RSV restored SERCA2 promoter activity, which was otherwise highly repressed in high-glucose media. Protective effects of RSV were found to be dependent on its ability to activate Silent information regulator (SIRT) 1. In cardiomyocytes, overexpression of SIRT1 was found sufficient to activate SERCA2 promoter in a dose-dependent manner. In contrast, pretreatment of cardiomyocytes with SIRT1 antagonist, splitomycin, blocked these beneficial effects of RSV. In addition, SIRT1 knockout (+/-) mice were also found to be more sensitive to STZ-induced decline in SERCA2a mRNA. The data demonstrate that, in chronic diabetes, 1) the enzymatic activity of cardiac SIRT1 is reduced, which contributes to reduced expression of SERCA2a and 2) through activation of SIRT1, RSV enhances expression of SERCA2a and improves cardiac function. AIM: To study whether calcium-modulating proteins CASQ2, FKBP12.6 and SERCA2a participate in diabetic cardiomyopathy, and whether the beneficial actions of testosterone, sildenafil or fructose diphosphate Sr (FDP-Sr) in the treatment of diabetic cardiomyopathy result from suppressing these molecules. METHODS: Fifty male Sprague-Dawley (SD) rats were divided into five groups. Except for the normal group (non-diabetic), the other four groups were injected with streptozotocin (STZ, 60 mg/kg, ip) to induce diabetes. Four weeks after STZ injection, the four groups received sildenafil (12 mg·kg(-1)·d(-1), ig, for 4 week), FDP-Sr (200 mg/kg, ig, for 4 week), testosterone propionate (4 mg·kg(-1)·d(-1), sc, for 4 week), or no treatment, respectively. RESULTS: In the diabetic rats, blood glucose, free fatty acids, triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) were significantly increased, while high-density lipoprotein cholesterol (HDL-C) was significantly reduced, as compared to the non-diabetic rats. Cardiac dysfunction and myocardial hypertrophy of the diabetic rats were associated with increased mRNA and protein expression of iNOS, OBRb, and PKCɛ, while expression of CASQ2, SERCA2a, and FKBP12.6 was significantly down-regulated. Sildenafil and FDP-Sr, but not testosterone, significantly attenuated the biomarker abnormalities, without changing the metabolic abnormalities. CONCLUSION: CASQ2, FKBP12.6 and SERCA2a were down-regulated in diabetic cardiomyopathy. Sildenafil and FDP-Sr, but not testosterone, attenuated the cardiac dysfunction in diabetic cardiomyopathy, without changing the metabolic abnormalities, which may results from inhibiting oxidative and inflammatory cytokines and improving calcium homeostasis. Diabetic cardiomyopathy (DCM) is a diabetic complication, which results in myocardial dysfunction independent of other etiological factors. Abnormal intracellular calcium ([Ca(2+)](i)) homeostasis has been implicated in DCM and may precede clinical manifestation. Studies in cardiomyocytes have shown that diabetes results in impaired [Ca(2+)](i) homeostasis due to altered sarcoplasmic reticulum Ca(2+) ATPase (SERCA) and sodium-calcium exchanger (NCX) activity. Importantly, altered calcium homeostasis may also be involved in diabetes-associated endothelial dysfunction, including impaired endothelium-dependent relaxation and a diminished capacity to generate nitric oxide (NO), elevated cell adhesion molecules, and decreased angiogenic growth factors. However, the effect of diabetes on Ca(2+) regulatory mechanisms in cardiac endothelial cells (CECs) remains unknown. The objective of this study was to determine the effect of diabetes on [Ca(2+)](i) homeostasis in CECs in the rat model (streptozotocin-induced) of DCM. DCM-associated cardiac fibrosis was confirmed using picrosirius red staining of the myocardium. CECs isolated from the myocardium of diabetic and wild-type rats were loaded with Fura-2, and UTP-evoked [Ca(2+)](i) transients were compared under various combinations of SERCA, sarcoplasmic reticulum Ca(2+) ATPase (PMCA) and NCX inhibitors. Diabetes resulted in significant alterations in SERCA and NCX activities in CECs during [Ca(2+)](i) sequestration and efflux, respectively, while no difference in PMCA activity between diabetic and wild-type cells was observed. These results improve our understanding of how diabetes affects calcium regulation in CECs, and may contribute to the development of new therapies for DCM treatment. BACKGROUND: Calcium (Ca2+) handling proteins are known to play a pivotal role in the pathophysiology of cardiomyopathy. However little is known about early changes in the diabetic heart and the impact of insulin treatment (Ins). METHODS: Zucker Diabetic Fatty rats treated with or without insulin (ZDF ± Ins, n = 13) and lean littermates (controls, n = 7) were sacrificed at the age of 19 weeks. ZDF + Ins (n = 6) were treated with insulin for the last 6 weeks of life. Gene expression of Ca2+ ATPase in the cardiac sarcoplasmatic reticulum (SERCA2a, further abbreviated as SERCA) and phospholamban (PLB) were determined by northern blotting. Ca2+ transport of the sarcoplasmatic reticulum (SR) was assessed by oxalate-facilitated 45Ca-uptake in left ventricular homogenates. In addition, isolated neonatal cardiomyocytes were stimulated in cell culture with insulin, glucose or triiodthyronine (T3, positive control). mRNA expression of SERCA and PLB were measured by Taqman PCR. Furthermore, effects of insulin treatment on force of contraction and relaxation were evaluated by cardiomyocytes grown in a three-dimensional collagen matrix (engineered heart tissue, EHT) stimulated for 5 days by insulin. By western blot phosphorylations status of Akt was determed and the influence of wortmannin. RESULTS: SERCA levels increased in both ZDF and ZDF + Ins compared to control (control 100 ± 6.2 vs. ZDF 152 ± 26.6* vs. ZDF + Ins 212 ± 18.5*# % of control, *p < 0.05 vs. control, #p < 0.05 vs. ZDF) whereas PLB was significantly decreased in ZDF and ZDF + Ins (control 100 ± 2.8 vs. ZDF 76.3 ± 13.5* vs. ZDF + Ins 79.4 ± 12.9* % of control, *p < 0.05 vs control). The increase in the SERCA/PLB ratio in ZDF and ZDF ± Ins was accompanied by enhanced Ca2+ uptake to the SR (control 1.58 ± 0.1 vs. ZDF 1.85 ± 0.06* vs. ZDF + Ins 2.03 ± 0.1* μg/mg/min, *p < 0.05 vs. control). Interestingly, there was a significant correlation between Ca2+ uptake and SERCA2a expression. As shown by in-vitro experiments, the effect of insulin on SERCA2a mRNA expression seemed to have a direct effect on cardiomyocytes. Furthermore, long-term treatment of engineered heart tissue with insulin increased the SERCA/PLB ratio and accelerated relaxation time. Akt was significantly phosphorylated by insulin. This effect could be abolished by wortmannin. CONCLUSION: The current data demonstrate that early type 2 diabetes is associated with an increase in the SERCA/PLB ratio and that insulin directly stimulates SERCA expression and relaxation velocity. These results underline the important role of insulin and calcium handling proteins in the cardiac adaptation process of type 2 diabetes mellitus contributing to cardiac remodeling and show the important role of PI3-kinase-Akt-SERCA2a signaling cascade.

Is pesticide exposure associated with polyneuropathy?

Yes, it is associated with peripheral neuropathy.

A follow-up (1985, 1990, 1991) study revealed in female workers of hydroponic hothouses an increase of the incidence of nervous system diseases depending on the length of work (vegeto-vascular dystonia, angiodystonic syndromes, vegeto-sensory polyneuropathy). It is suggested that the main cause of nervous lesions in these cases was the complex effect of pesticides. Isolated case reports have circumstantially linked the use of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) to polyneuropathy. However, a critical review of the literature reveals numerous reasons for doubting a relationship of 2,4-D to polyneuropathy: (1) too few cases given the wide use of the chemical; (2) no valid toxicologic or epidemiologic evidence; (3) the diversity of antecedent illness; (4) an unlikely time sequence of antecedent illness to exposure (pharmacokinetics); (5) the lack of polyneuropathy in medical patients given repetitive doses of 2,4-D; (6) the lack of polyneuropathy in heavily exposed military personnel involved in operation Ranch Hand; (7) the biological properties of 2,4-D which minimize penetration of 2,4-D into the nervous system under normal exposure conditions; and (8) the lack of polyneuropathy in a variety of experimental animal species given 2,4-D by several routes of exposure and at dose levels and durations of exposure many times greater than human applicator exposure. Thus, the weight of evidence indicates that 2,4-D is an unlikely cause of polyneuropathy. A patient is reported presenting a cerebellar disorder developing about 5 weeks after acute exposure to an organophosphate insecticide. Initially no major cholinergic features were observed. The ataxia of delayed onset was not accompanied by clinical or electrophysiological signs of polyneuropathy. The possible pathogenetic mechanisms are reviewed and discussed. This case illustrates the need to closely monitor all patients intoxicated with such chemicals for at least 5 weeks. One should not only keep in mind the well-known late-onset polyneuropathy, but also the less frequent delayed central nervous system effects, even in the milder cases where initial signs of acetylcholine excess are only minimally present or lacking. While the health of the general population is not adversely affected by the exposure the pesticides in food and environment, workers, who have during their occupation been intensely exposed to pesticides, exhibit a higher prevalence of slight neurotoxic symptoms. In the present study the electroencephalograms of 3 of a group 10 workmen, who had been continually exposed to hexachlorcyclohexane, show pathological findings. The electromyograms of 8 of these 10 workman demonstrate a disturbance of the peripherical motoneuron. All probands, who exhibit o pathological EEG, also show a polyneuropathy. This pilot-study should contribute to the question whether Pyrethroid intoxication can be distinguished from other diseases by characteristic clinical symptoms. The results show that the characteristics of the intoxication do not consist in singular symptoms but in combinations and correlations of symptoms, i.e. of central-neurological with peripheral- and autonomic-neurological as well as with characteristic immunological disturbances. Neurological symptoms consist in cerebro-organic disfunctions, locomotory disorders reminiscent of multiple sclerosis or M. Parkinson, and sensory, motoric and vegetative polyneuropathy, leading, for instance, to cardiovascular regulatory disorder like sympathicotonia or, orthostatic hypotonia. Non-neurological symptoms include immunosuppression with consecutive opportunistic infections, like candida albicans, most frequently of the alimentary tract, but also dermal and mucosal swellings, lichen-ruber-like efflorescences, loss of hair, conjunctivitis. Other symptoms are: hypoglycaemic crises inhibition of fertility, disturbances of blood clotting, and most frequently in children, suspected hematopoetic disorders. During 1990 to 1991, through a national surveillance program for poliomyelitis, the Paraguayan Ministry of Health received reports of 50 children with incident acute flaccid paralysis (< 15 years old). On the basis of established criteria, 37 were diagnosed with Guillain-Barré syndrome. The average annual incidence rate for 1990 to 1991 was 1.1/100,000 children. The clinical course was more benign than reported in other pediatric series. There were low rates of hospitalization (57%), respiratory compromise (8%), and intubation (5%). The overall severity, however, was similar to that described in previous reports, with a 3% case-fatality rate and an 81% total recovery rate at 12 months. Seventy-six percent of patients had symptom onset during January to April, the warmest months of the year. Thirty percent of patients had definite or possible exposure to organophosphate pesticides, and the peak use coincides with the peak incidence of Guillain-Barré syndrome. There was no correlation between occurrence of Guillain-Barré syndrome and prior immunization. To evaluate chronic effects of acute organophosphate pesticide poisoning, quantitatively determined vibrotactile thresholds were measured as an index of peripheral neuropathy among agricultural workers in Nicaragua. Thirty-six male workers were evaluated between 10 and 34 months after hospitalization for acute organophosphate poisoning and compared to an age- and sex-matched community reference group. Vibrotactile thresholds were measured quantitatively in right and left index fingers and right and left great toes. Study subjects were stratified into three groups: 1) never poisoned; 2) poisoned with organophosphates other than methamidophos, agents which have not been reported to cause peripheral neuropathy; and 3) poisoned with methamidophos, a peripheral neurotoxin. For all digits, there was a statistically significant trend of increasing age- and height-adjusted thresholds across these three exposure categories. Over one fourth of patients previously poisoned with methamidophos we studied had abnormal vibrotactile thresholds. These results suggest that previously reported cases of organophosphate-induced delayed polyneuropathy may represent only the worst disease in a spectrum of impairment, a sequela of exposure that may be much more common than previously thought. Eighty-six workers exposed to zinc phosphide (Zn3P2) pesticide were studied for evidence of neuropsychiatric manifestations. They were evaluated clinically, by electroencephalography (EEG), and, in some cases, by electromyography (EMG). All were males (mean age, 35.8 years; mean duration of exposure to zinc phosphide, 11.3 years). Most presented with one (or more) neuropsychiatric symptom(s), including fear of poisoning, anxiety, impotence, and easy fatigue. About half showed evidence of neuropsychiatric signs, including hyperreflexia, polyneuropathy, lumber radiculopathy, and cervical myelopathy, as well as anxious mood, impaired attention, and psychomotor stimulation. EEG recordings showed abnormal findings in 17.4% of the subjects. The mean age in that group was 39.1 years; mean duration of exposure to Zn3P2 was 15.1 years. EMG studies showed evidence of partial denervation of the anterior tibial group of muscles and flexor digiti minimi in 2 of the 30 workers (6.7%) who underwent EMG examination. Serum levels of zinc (Zn) and cadmium (Ca) were significantly higher in exposed workers than in controls (P < 0.005). Serum copper (Cu), iron (Fe), phosphorus (P), and magnesium (Mg) were significantly lower in exposed workers than in controls. Electrophoretic pattern of globulin showed that gammaglobulin fraction was significantly increased (P < 0.005); alpha2 and beta-globulin were decreased (P < 0.005) in exposed workers. Lipoprotein pattern showed that the total lipids, B-lipoprotein, and B/alpha ratio were significantly increased (P < 0.005) in exposed workers; the alpha1 lipoprotein was decreased. Triglycerides and cholesterol were significantly increased (P < 0.001), and phospholipids and phospholipid/cholesterol ratio were significantly decreased (P < 0.005) in exposed workers compared to controls. The study findings indicated that exposure to Zn3P2 not only caused mild acute and subacute liver cell damage, but also affected renal function and perhaps B-cells of the pancreas. A total of 68.6% of the exposed workers had chest symptoms; only 24.4% presented with chest or cardiac signs. Ventilatory functions were abnormal in 70% of the exposed workers; abnormal ECG findings were present in 12.8%. The use of pesticides has extensively grown in the last decades, regardless of the economic level of the countries. This led to great improvements in agriculture but also a threat for human health. Short term effects are quite well known through approval procedures for pesticides. On the other hand, long term effects are not properly assessed. A review of epidemiologic knowledge is presented here. Epidemiologic studies on pesticides have found associations with long-term effects on health mainly in three fields: cancer (especially hematological cancer), neurotoxic effects (polyneuropathy, neuro-behavioral hazards, Parkinson's disease), and reproductive disorders (infertility, birth defects, adverse pregcy outcomes, perinatal mortality). These conclusions have been obtained despite difficulties in exposition assessment due to the retrospective nature of the studies. But the continuous development of pesticide use in agriculture, and also in domestic environment, emphasizes the need for epidemiologic studies on long-term effects of pesticides relying on accurate exposure assessment. INTRODUCTION: Organophosphate esters are widely used both in agriculture and in industry and may give rise to acute intoxication due to their direct anticholinesterase effect. Less often a polyneuropathic syndrome of late onset may occur. This is predomitly motor, symmetrical, with muscle atrophy and pyramidal signs. These neurotoxic features are due to inhibition of the target esterase of this neuropathy. Histopathological studies show axon degeneration of 'dying back' type. CLINICAL CASE: We present the case of a 24 year old man with severe sensomotor neuropathy, predomitly distal, with marked atrophy of the interosseus muscles, claw hand and foot drop, together with increased deep tendon reflexes. This patient had worked on the land, cultivating maize, from the age of 14, when his symptoms began and became progressively worse. On electromyography there was sensomotor peripheral polyneuropathy, which was primarily axonal and predomitly motor and distal. Peripheral nerve biopsy confirmed the presence of 'dying back' type axonopathy. Extensive biochemical investigations ruled out other causes of polyneuropathy. Cerebral resoce study was normal. CONCLUSIONS: Agricultural workers chronically exposed to organophosphate insecticides, without adequate protection, have an increased risk of developing late onset neuropathy due to organophosphates. The risk of developing late onset neuropathy is not necessarily related to a history of acute intoxication, since chronic sublethal exposure may mean that previous acute anticholinergic symptoms pass undetected. BACKGROUND: The aim of this study was to find out the indicator as a marker of person who are exposed to pesticides (organophospate). Up to now the serum cholinesterase is used as a marker. This new method will not taking blood vein since this be the obstacle in conducting research in a rural area. METHODS: A cross sectional study was conducted to investigate the effect of pesticide exposure on the activity of serum cholinesterase (ChE) and current perception threshold (CPT). The samples are 60 paddy farmers (exposed group) and control group taken from the office of Muda agricultural area of Kedah in 19 do not expose to pesticide. The CPT values measured using a portable constant current electric nerve stimulator, Neurometer CPT/Eagle (Neurotron Incorporated, Baltimore, USA). Assessments carried out by one examiner on the index finger (median digital nerve) and the great toe (peroneal digital nerve). The current used are 3 neuroselective frequency range 2000 Hz, 250 Hz, and 5 Hz. The serum cholinesterase activity measured spectrophotometrically using cholinesterase inhibition test kit CHE MHE 1,144729. RESULT: It was significantly evident that the serum cholinesterase activity noted reduced among the paddy farmers (p = 0.014). The CPT values were significantly elevated for the 2000 Hz frequency range for both the measurement sites (index finger p < 0.0001 and great toe p < 0.0001). For the 250 Hz frequency range CPT values were significant only for the index finger (p = 0.012). However there was no significant difference for the 5 Hz frequency range. There was also a significant correlation (negative) between CPT values and serum cholinesterase activity more for the 2000 Hz frequency range (index finger r = 0.672, p < 0.0001 & for great toe r = 0.736, p < 0.0001). The results were suggestive of subclinical impairment of distal axonopathy considering the fact only 25% of the farmer showed clinical manifestation of numbness. CONCLUSION: The selective involvement of the large diameter sensory fibres (250 Hz and 2000 Hz) were reflective of toxic peripheral neuropathy. Neurometer CPT/Eagle used as indicator for detecting the effect of pesticide instead of using cholinesterase enzyme activity. Organophosphorous compounds, the anticholinesterases, produce significant morbidity and mortality in India. Although exact estimates are not available, hospital based statistics suggest that nearly half of the admissions to emergency with acute poisoning are due to organophosphates. Following accidental or suicidal exposure, these anticholinesterases lead to three well defined neurological syndromes i.e. initial life threatening acute cholinergic crisis which often requires management in intensive care unit, intermediate syndrome in which cranial nerve palsies, proximal muscle weakness and respiratory muscle weakness are common and patients often require respiratory support and delayed organophosphate induced polyneuropathy. In addition to these three classical neurological syndromes following acute exposure and in some following low dose chronic exposure, several neurobehavioural changes have been observed and these have been termed together as 'chronic organophosphate induced neuropsychiatric disorders' (COPIND). Organo-phosphate compounds produce significant pesticide related illness in developing countries. There is, thus, a need to determine exact extent of the problem and to develop appropriate strategies to manage these cases with available resources in these countries. OBJECTIVES: To investigate the hypothesis that chronic low level exposure to organophosphates (OPs) in sheep dips is related to clinically detectable measures of polyneuropathy. METHODS: The design was a cross sectional exposure-response study of sheep dippers and other non-exposed groups. The study group consisted of 612 sheep dipping farmers, 53 farmers with no sheep dipping experience, and 107 ceramics workers. Retrospective exposure information was obtained by questionnaire based on stable and easily identifiable features of sheep dipping found during the first phase of the study; in particular, estimates of handling concentrate and splashing with dilute dip. Neurological assessments were based on a standard neuropathy symptoms questionnaire, and thermal and vibration quantitative sensory tests. RESULTS: Adjusted for confounders there was a weak positive association between cumulative exposure to OPs and neurological symptoms, the significance of which was dependent on the inclusion of a few individual workers with extremely high exposure. There was no evidence of an association between cumulative exposure and the thermal or vibration sensory thresholds. However, separating the effects of exposure intensity and duration showed a higher prevalence of symptoms, primarily of a sensory type, among sheep dippers who handled the OP concentrate. There was also evidence that sensory and vibration thresholds were higher among concentrate handlers, the highest exposed group of dippers. CONCLUSIONS: The findings showed a strong association between exposure to OP concentrate and neurological symptoms, but a less consistent association with sensory thresholds. There was only weak evidence of a chronic effect of low dose cumulative exposure to OPs. It is suggested that long term health effects may occur in at least some sheep dippers exposed to OPs over a working life, although the mechanisms are unclear. The course of organophosphate-induced delayed polyneuropathy (OPIDP) in humans has not been quantitatively measured in epidemiologic studies. This study evaluated the association of acute OP poisonings with motor neurologic impairment. Hand grip and pinch strength were evaluated among 62 Nicaraguan men hospitalized for acute OP poisoning between 1992 and 1996; 39 cattle ranchers and fishermen who had never experienced pesticide poisoning were controls. Exposure categories were moderate and severe poisonings with neuropathic and non-neuropathic OPs. Strength was measured at hospital discharge and seven weeks after poisoning. Grip and pinch strength were impaired among all OP-poisoned subjects at both examinations, more noticeably among those poisoned with OPs with suspected neuropathic effects, methamidophos and chlorpyrifos. In those with severe poisonings with neuropathic OPs, impairments were more marked among intentional than among occupational poisonings. The performances of suicidal subjects worsened at the second examination, consistent with OPIDP. Early motor impairment at the time of hospital discharge is consistent with cholinergic depolarization blockade after acute poisoning. The persistence of deficits in motor strength in all severely poisoned patients regardless of pesticide type was unexpected, and may reflect persistent cholinergic blockade or intermediate syndrome, neuropathy, or a combination of these. Intoxications due to organophosphate insecticides are common in our country, since agriculture has an important place. Besides the well known acute cholinergic toxicity, these compounds may cause late-onset distal polyneuropathy occurring two to three weeks after the acute exposure. An eight-year-old boy and a 13-year-old girl admitted to the hospital with gait disturbances. Beginning 15 and 20 days, respectively, after organophosphate ingestion. Neurologic examination revealed bilateral dropped foot, absent Achilles tendon reflexes and peripheral sensory loss. Electromyography demonstrated motor weighed sensory-motor polyneuropathy with axonal degeneration significant in the distal parts of bilateral lower extremities. Biochemical, radiological findings and magnetic resoce imagings were normal. The two cases were taken under a physiotherapy program. The two cases are presented here since organophosphate poisonings are common in our country, and since late-onset polyneuropathy is not a well known clinical presentation as acute toxicity. AIMS: To evaluate the association of acute organophosphate (OP) poisoning with chronic sensory and motor neurological impairment. METHODS: This study concerns the third of a series of three examinations of hand strength and vibration thresholds in a two year period after acute OP poisoning among 48 Nicaraguan men. The first two examinations were performed at hospital discharge and seven weeks after poisoning, and the present examination two years later. Twenty eight cattle ranchers and fishermen who had never experienced pesticide poisoning were examined as controls, also three times over the two year period. The poisonings were categorised as caused by "non-neuropathic" OPs and "neuropathic" OPs, each subdivided in moderate and severe poisonings. RESULTS: Men poisoned with OP insecticides had persistent reduced hand strength. We previously reported weakness at hospital discharge for OP poisoned in all categories that worsened seven weeks later for those severely poisoned with neuropathic OPs. Strength improved over time, but the poisoned were still weaker than controls two years after the poisoning, most noticeably among the subjects most severely poisoned with neuropathic OPs. Also, index finger and toe vibration thresholds were slightly increased at the end of the two year period, among men with OP poisonings in all categories, but patterns of onset and evolvement of impairment of vibration sensitivity were less clear than with grip and pinch strength. CONCLUSIONS: Persistent, mainly motor, impairment of the peripheral nervous system was found in men two years after OP poisoning, in particular in severe occupational and intentional poisonings with neuropathic OPs. This finding is possibly due to remaining organophosphate induced delayed polyneuropathy. Several studies have reported the occurrence of sensory neuropathy with exposure to chlorpyrifos and other organophosphorus insecticides, at levels not associated with overt toxicity. We evaluated 113 chemical workers, including 53 of 66 (80%) eligible chlorpyrifos workers and 60 of 74 (81%) randomly selected referent workers, to identify evidence of sensory neuropathy or subclinical neuropathy. Compared to referents, chlorpyrifos subjects had significantly longer duration of work in chlorpyrifos-exposed areas (9.72 vs. 0.01 years; P < 0.0001), greater cumulative chlorpyrifos exposure (64.16 vs. 0.69 mg/m(3). day; P < 0.0001), higher urine 3,5,6-trichloro-2-pyridinol (TCP) excretion (108.6 vs. 4.3 microg/g creatinine; P < 0.0001), and lower plasma butyrylcholinesterase (BuChE) activity (7281 vs. 8176 mU/ml; P = 0.003). Despite exposures among chlorpyrifos subjects to levels at which well-described physiological effects on B-esterases exist, the frequency of symptoms or signs of neuropathy did not differ significantly between groups, and the only 2 subjects fulfilling criteria for confirmed neuropathy were both in the referent group. Mean nerve conduction study results were comparable to established control values and did not differ significantly between groups. We found no evidence of sensory neuropathy or isolated peripheral abnormalities among subjects with long-term chlorpyrifos exposure at levels known to be associated with the manufacturing process. Organophosphate-induced delayed polyneuropathy (OPIDP) is a rare toxicity resulting from exposure to certain organophosphorus (OP) esters. It is characterised by distal degeneration of some axons of both the peripheral and central nervous systems occurring 1-4 weeks after single or short-term exposures. Cramping muscle pain in the lower limbs, distal numbness and paraesthesiae occur, followed by progressive weakness, depression of deep tendon reflexes in the lower limbs and, in severe cases, in the upper limbs. Signs include high-stepping gait associated with bilateral foot drop and, in severe cases, quadriplegia with foot and wrist drop as well as pyramidal signs. In time, there might be significant recovery of the peripheral nerve function but, depending on the degree of pyramidal involvement, spastic ataxia may be a permanent outcome of severe OPIDP. Human and experimental data indicate that recovery is usually complete in the young. At onset, the electrophysiological changes include reduced amplitude of the compound muscle potential, increased distal latencies and normal or slightly reduced nerve conduction velocities. The progression of the disease, usually over a few days, may lead to non-excitability of the nerve with electromyographical signs of denervation. Nerve biopsies have been performed in a few cases and showed axonal degeneration with secondary demyelination. Neuropathy target esterase (NTE) is thought to be the target of OPIDP initiation. The ratio of inhibitory powers for acetylcholinesterase and NTE represents the crucial guideline for the aetiological attribution of OP-induced peripheral neuropathy. In fact, pre-marketing toxicity testing in animals selects OP insecticides with cholinergic toxicity potential much higher than that to result in OPIDP. Therefore, OPIDP may develop only after very large exposures to insecticides, causing severe cholinergic toxicity. However, this was not the case with certain triaryl phosphates that were not used as insecticides but as hydraulic fluids, lubricants and plasticisers and do not result in cholinergic toxicity. Several thousand cases of OPIDP as a result of exposure to tri-ortho-cresyl phosphate have been reported, whereas the number of cases of OPIDP as a result of OP insecticide poisoning is much lower. In this article, we mainly discuss OP pesticide poisoning, particularly when caused by chlorpyrifos, dichlorvos, isofenphos, methamidophos, mipafox, trichlorfon, trichlornat, phosphamidon/mevinphos and by certain carbamates. We also discuss case reports where neuropathies were not convincingly attributed to fenthion, malathion, omethoate/dimethoate, parathion and merphos. Finally, several observational studies on long-term, low-level exposures to OPs that sometimes reported mild, inconsistent and unexplained changes of unclear significance in peripheral nerves are briefly discussed. Organophosphorous pesticides (OPs) are suspected of altering reproductive function by reducing brain acetylcholinesterase activity and monoamine levels, thus impairing hypothalamic and/or pituitary endocrine functions and gonadal processes. Our objective was to evaluate in a longitudinal study the association between OP exposure and serum levels of pituitary and sex hormones. Urinary OP metabolite levels were measured by gas-liquid chromatography, and serum pituitary and sex hormone levels by enzymatic immunoassay and radioimmunoassay in 64 men. A total of 147 urine and blood samples were analyzed for each parameter. More than 80% of the participants had at least one OP metabolite in their urine samples. The most frequent metabolite found was diethylthiophosphate (DETP; 55%), followed by diethylphosphate (DEP; 46%), dimethylthiophosphate (DMTP; 32%), and dimethyldithiophosphate (DMDTP; 31%). However, the metabolites detected at higher concentrations were DMTP, DEP, DMDTP, and dimethylphosphate. There was a high proportion of individuals with follicle-stimulating hormone (FSH) concentrations outside the range of normality (48%). The average FSH serum levels were higher during the heavy pesticide spraying season. However, a multivariate analysis of data collected in all periods showed that serum FSH levels were negatively associated with urinary concentrations of both DMTP and DMDTP, whereas luteinizing hormone (LH) was negatively associated with DMTP. We observed no significant associations between estradiol or testosterone serum levels with OP metabolites. The hormonal disruption in agricultural workers presented here, together with results from experimental animal studies, suggests that OP exposure disrupts the hypothalamic-pituitary endocrine function and also indicates that FSH and LH are the hormones most affected. The purpose of this case series is to assess long-term sequelae of arsenic exposure in a cohort acutely exposed to arsenic in drinking water from a well dug into a landfill containing arsenical pesticides. Ten of the 13 individuals (or next of kin) in the initial study agreed to participate in the follow-up study. Next of kin provided questionnaire data and released medical information on the three individuals who had died. The remaining seven cohort members were assessed by an interview, questionnaire, detailed physical examination and sensory nerve testing. Available medical records were obtained and reviewed. Sensory testing was performed using an automated electrodiagnostic sensory Nerve Conduction Threshold (sNCT) evaluation. Sensory complaints and electrodiagnostic findings consistent with polyneuropathy were found in a minority (3/7) of subjects 28 years after an acute toxic arsenic exposure. Two of the seven patients examined (1 of 3 with neuropathic findings) also had hyperkeratotic lesions consistent with arsenic toxicity and one of the patients had hyperpigmentation on their lower extremities possibly consistent with arsenic toxicity. The intermediate syndrome (IMS) following organophosphorus (OP) insecticide poisoning was first described in the mid-1980s. The syndrome described comprised characteristic symptoms and signs occurring after apparent recovery from the acute cholinergic syndrome. As the syndrome occurred after the acute cholinergic syndrome but before organophosphate-induced delayed polyneuropathy, the syndrome was called 'intermediate syndrome'. The IMS occurs in approximately 20% of patients following oral exposure to OP pesticides, with no clear association between the particular OP pesticide involved and the development of the syndrome. It usually becomes established 2-4 days after exposure when the symptoms and signs of the acute cholinergic syndrome (e.g. muscle fasciculations, muscarinic signs) are no longer obvious. The characteristic features of the IMS are weakness of the muscles of respiration (diaphragm, intercostal muscles and accessory muscles including neck muscles) and of proximal limb muscles. Accompanying features often include weakness of muscles innervated by some cranial nerves. It is now emerging that the degree and extent of muscle weakness may vary following the onset of the IMS. Thus, some patients may only have weakness of neck muscles whilst others may have weakness of neck muscles and proximal limb muscles. These patients may not require ventilatory care but close observation and monitoring of respiratory function is mandatory. Management is essentially that of rapidly developing respiratory distress and respiratory failure. Delays in instituting ventilatory care will result in death. Initiation of ventilatory care and maintece of ventilatory care often requires minimal doses of non-depolarising muscle relaxants. The use of depolarising muscle relaxants such as suxamethonium is contraindicated in OP poisoning. The duration of ventilatory care required by patients may differ considerably and it is usual for patients to need ventilatory support for 7-15 days and even up to 21 days. Weaning from ventilatory care is best carried out in stages, with provision of continuous positive airway pressure prior to complete weaning. Continuous and close monitoring of respiratory function (arterial oxygen saturation, partial pressure of oxygen in arterial blood, partial pressure of carbon dioxide in arterial blood) and acid-base status are an absolute necessity. Prophylactic antibiotics are usually not required unless there has been evidence of aspiration of material into the lungs. Close monitoring of fluid and electrolyte balance is mandatory in view of the profuse offensive diarrhoea that most patients develop. Maintece of nutrition, physiotherapy, prevention of bed sores and other routine measures to minimise discomfort during ventilatory care are necessary. Recovery from the intermediate syndrome is normally complete and without any sequelae. The usefulness of oximes during the IMS remains uncertain. In animal experiments, very early administration of oximes has prevented the occurrence of myopathy. There are reports from developed countries where administration of oximes at recommended doses and within 2 hours of ingestion of OP insecticide did not prevent the onset of the IMS. Controlled randomised clinical studies are necessary to evaluate the efficacy of oximes in combating the IMS. Electrophysiological studies following OP poisoning have revealed three characteristic phenomena: (i) repetitive firing following a single stimulus; (ii) gradual reduction in twitch height or compound muscle action potential followed by an increase with repetitive stimulation (the 'decrement-increment response'); and (iii) continued reduction in twitch height or compound muscle action potential with repetitive simulation ('decrementing response'). Of these, the decrementing response is the most frequent finding during the IMS, whilst repetitive firing is observed during the acute cholinergic syndrome. The distribution of the weakness in human cases of the IMS, in general, parallels the distribution of the myopathy observed in a number of studies in experimental animals. This has led to speculation that myopathy is involved in the causation of the IMS. However, while myopathy and the IMS have a common origin in acetylcholine accumulation, they are not causally related to one another. BACKGROUND: Organophosphorus pesticides such as chlorpyrifos and malathion are widely used insecticides. They do not bioaccumulate appreciably in humans and are rapidly metabolized and excreted in the urine. In nonoccupational settings, exposures to these pesticides are typically sporadic and short-lived because the pesticides tend to degrade in the environment over time; however, dietary exposures may be more chronic. Biologic monitoring has been widely used to assess exposures, susceptibility, and effects of chlorpyrifos and malathion; thus, the information base on these compounds is data rich. For biomonitoring of exposure, chlorpyrifos and malathion have been measured in blood, but most typically their urinary metabolites have been measured. For assessing early effects and susceptibility, cholinesterase and microsomal esterase activities, respectively, have been measured. OBJECTIVES: Although many biologic monitoring data have been generated and published on these chemicals, their interpretation is not straightforward. For example, exposure to environmental degradates of chlorpyrifos and malathion may potentially increase f urinary metabolite levels, thus leading to overestimation of exposure. Also, the temporal nature of the exposures makes the evaluation of both exposure and effects difficult. We present an overview of the current biomonitoring and other relevant data available on exposure to chlorpyrifos and malathion and the use of these data in various environmental public health applications. Organophosphates (OPs) are commonly used as pesticides throughout the world. Exposures to OPs cause a significant number of poisonings and deaths every year. Organophosphate-induced delayed polyneuropathy is a sensory-motor distal axonopathy which usually occurs after exposure of certain OP insecticides. Neuropathies due to ingestion of OPs have rarely been reported in the literature. Moreover, until now, there is no report of a patient developing organophosphorus injection-induced delayed neuropathy in the literature. We report a patient with serious organophosphorus-induced delayed neuropathy due to malathion injection. The patient was a 32-year-old female who self-injected undetermined amounts of malathion over the median nerve trace on the forearm crease in a suicide attempt which resulted in peripheral neuropathy. Acute poisoning by organophosphorus (OP) compounds is a major global clinical problem, with thousands of deaths occurring every year. Most of these pesticide poisoning and subsequent deaths occur in developing countries following a deliberate self ingestion of the poison. Metacid (Methyl parathion) and Nuvan (Dichlorovos) are commonly ingested OP pesticides; Dimethoate, Profenofos, and Chlorpyrifos are other less frequently ingested compounds in Nepal. The toxicity of these OP pesticides is due to the irreversible inhibition of acetylcholinesterase (AChE) enzyme leading to accumulation of acetylcholine and subsequent over-activation of cholinergic receptors in various parts of the body. Acutely, these patients present with cholinergic crisis; intermediate syndrome and delayed polyneuropathy are other sequel of this form of poisoning. The diagnosis depends on the history of exposure to these pesticides, characteristic manifestations of toxicity and improvements of the signs and symptoms after administration of atropine. The supportive treatment of OP poisoning includes the same basic principles of management of any acutely poisoned patient i.e., rapid initial management of airways, breathing, and circulation. Gastric lavage and activated charcoal are routinely used decontamination procedures, but their value has not been conclusively proven in this poisoning. Atropine is the mainstay of therapy, and can reverse the life threatening features of this acute poisoning. However, there are no clear cut guidelines on the dose and duration of atropine therapy in OP poisoning. Cholinesterase reactivators, by regenerating AChE, can reverse both the nicotinic and muscarinic effects; however, this benefit has not been translated well in clinical trials. All these facts highlight that there are many uswered questions and controversies in the management of OP poisoning and there is an urgent need for research on this aspect of this common and deadly poisoning. Pesticides are used extensively throughout the world in agriculture and in pest control as well as for community health purposes. Organophosphate (OP) pesticide self-poisoning is an important clinical problem in rural regions of the developing world that kills an estimated 200,000 people every year. Unintentional poisoning kills far fewer people but is an apparent problem in places where highly toxic OP pesticides are available. Neurologic dysfunction is the best documented health effect of pesticide exposure. High-level exposure has both acute and long-term neurologic signs and symptoms, and adverse effects have been reported in most type of pesticides, including organophosphate (OP), carbamate, organochlorine, and pyrethroid insecticides, herbicides, fungicides, and fumigants. Acute OP pesticide exposure can involve in wide range of both central and peripheral neurologic symptoms. Increased neurologic symptom prevalence may provide early evidence of neurologic dysfunctions, before clinically measurable signs are evident.In this study, we analyzed the cross-sectional data on neurologic signs and symptoms from 225 rural children, both males (n = 132) and females (n = 93) who were occupationally and paraoccupationally exposed to methyl OPs (dichlorvos, fenthion, malathion, methyl parathion) and ethyl OPs (chlorpyrifos, diazinon, ethyl parathion) as they belonged to agricultural families handling, mixing, and spraying the OP pesticides. The children completed a specially designed questionnaire (Q16) on neurologic symptoms associated with pesticide exposure with their parental help. A suitable reference group consisting of rural children (n = 50) never involved in pesticide handling (neither outdoor nor indoor) belonging to similar socioeconomic strata included in the study to compare the prevalence of various neurologic symptoms between the two groups.Among all the neurologic self-reported symptoms, headache, watering in eyes, and burning sensation in eye/face were the most important clinical manifestations attributed to OP pesticide exposure. These symptoms could probably be the consequence of chronic effects of most pesticides on the central nervous system. The muscarinic symptoms reported the maximum prevalence of salivation (18.22%), whereas lacrimation was observed in 17.33% cases, followed by diarrhea in 9.33% cases. The nicotinic clinical manifestations of acute OP poisoning revealed excessive sweating in 13.78% cases and tremors in 9.3% cases followed by mydriasis in 8.4% exposed children. The characteristic cholinergic symptoms, such as insomnia, headache, muscle cramps, weakness, and anorexia were also reported by both male and female exposed children. The high frequency of neurologic symptoms observed in the study may be due to parasympathetic hyperactivity due to the accumulated ACh resulting from AChE inhibition. The aim of this paper was to provide an overview of mortality and disease prevalence related to occupational diseases among agricultural workers in Korea. We evaluated the age-standardized mortality rates and the prevalence of chronic diseases and compared them with those of other populations using death registration data from 2004 through 2008 and the 2005 Korean National Health and Nutrition Examination Survey. In addition, we conducted a literature review on published articles examining the health status of farmers in Korea. Agricultural workers have a significantly higher mortality of cancer, tuberculosis, chronic respiratory diseases, liver diseases, suicide, motor and non-motor vehicle accidents. Compared to other populations, farmers have higher prevalence rates of arthritis and intervertebral disc disorders. The literature review revealed a number of work-related diseases among farmers, such as musculoskeletal diseases, pesticide poisoning, infections, and respiratory and neurologic diseases. Korean farmers demonstrate a distinct pattern of mortality and disease prevalence compared to other populations. Although lifestyle factors remain important contributors to those deaths and diseases, our study suggests that occupation is a major determit as well. Intensive programs such as surveillance systems, therefore, should be developed in order to identify and prevent work-related diseases among agricultural workers in Korea. Toxic effects on eyes result from exposure to pesticides via inhalation, ingestion, dermal contact and ocular exposure. Exposure of unprotected eyes to pesticides results in the absorption in ocular tissue and potential ocular toxicity. Recent literature on the risks of ocular toxicity from pesticide exposure is limited.Ocular toxicity from pesticide exposure, including the dose-response relationship, has been studied in different animal species. Cholinesterase enzymes have been detected in animal ocular tissue, with evidence of organophosphate-induced inhibition. Pathological effects of pesticides have been observed in conjunctiva, cornea, lens, retina and the optic nerve. Pesticide exposure has been associated with retinopathy in agricultural workers and wives of farmers who used pesticides. Saku disease, an optico-autonomic peripheral neuropathy, has been described in Japan in people living in an area where organophosphates were used. Pesticide exposure is also associated with abnormal ocular movements.Progressive toxic ocular effects leading to defective vision are a serious health concern. Agricultural workers are at high risk of exposure to pesticides and associated ocular toxicity. Primary prevention is the appropriate method of protecting eyes from pesticide-related damage. This includes improved eye safety and care in workplaces, and effective pesticide regulation for maintece of public eye health. In this paper we review neurotoxic disorders appearing in patients poisoned with organophosphorus pesticides. These compounds cause four important neurotoxic effects in humans: the cholinergic syndrome, the intermediate syndrome, organophosphate-induced delayed polyneuropathy (OPIDP) and chronic organophosphate-induced neuropsychiatric disorder (COPIND). Compared to the cholinergic syndrome, that causes millions of cases of poisoning each year, other disorders involve much smaller numbers of patients. The review is focused on the neurotoxic effects appearing after acute and chronic exposure to organophosphates with emphasis on clinical presentation, pathogenesis, molecular mechanisms, and possibilities for prevention/therapy. Pesticides almost always occur in mixtures with other ones. The toxicological effects of low-dose pesticide mixtures on the human health are largely unknown, although there are growing concerns about their safety. The combined toxicological effects of two or more components of a pesticide mixture can take one of three forms: independent, dose addition or interaction. Not all mixtures of pesticides with similar chemical structures produce additive effects; thus, if they act on multiple sites their mixtures may produce different toxic effects. The additive approach also fails when evaluating mixtures that involve a secondary chemical that changes the toxicokinetics of the pesticide as a result of its increased activation or decreased detoxification, which is followed by an enhanced or reduced toxicity, respectively. This review addresses a number of toxicological interactions of pesticide mixtures at a molecular level. Examples of such interactions include the postulated mechanisms for the potentiation of pyrethroid, carbaryl and triazine herbicides toxicity by organophosphates; how the toxicity of some organophosphates can be potentiated by other organophosphates or by previous exposure to organochlorines; the synergism between pyrethroid and carbamate compounds and the antagonism between triazine herbicides and prochloraz. Particular interactions are also addressed, such as those of pesticides acting as endocrine disruptors, the cumulative toxicity of organophosphates and organochlorines resulting in estrogenic effects and the promotion of organophosphate-induced delayed polyneuropathy. This article schematically reviews the clinical features, diagnostic approaches to, and toxicological implications of toxic encephalopathy. The review will focus on the most significant occupational causes of toxic encephalopathy. Chronic toxic encephalopathy, cerebellar syndrome, parkinsonism, and vascular encephalopathy are commonly encountered clinical syndromes of toxic encephalopathy. Few neurotoxins cause patients to present with pathognomonic neurological syndromes. The symptoms and signs of toxic encephalopathy may be mimicked by many psychiatric, metabolic, inflammatory, neoplastic, and degenerative diseases of the nervous system. Thus, the importance of good history-taking that considers exposure and a comprehensive neurological examination cannot be overemphasized in the diagnosis of toxic encephalopathy. Neuropsychological testing and neuroimaging typically play ancillary roles. The recognition of toxic encephalopathy is important because the correct diagnosis of occupational disease can prevent others (e.g., workers at the same worksite) from further harm by reducing their exposure to the toxin, and also often provides some indication of prognosis. Physicians must therefore be aware of the typical signs and symptoms of toxic encephalopathy, and close collaborations between neurologists and occupational physicians are needed to determine whether neurological disorders are related to occupational neurotoxin exposure. Occupational neurotoxic diseases have become increasingly common in Taiwan due to industrialization. Over the past 40 years, Taiwan has transformed from an agricultural society to an industrial society. The most common neurotoxic diseases also changed from organophosphate poisoning to heavy metal intoxication, and then to organic solvent and semiconductor agent poisoning. The nervous system is particularly vulnerable to toxic agents because of its high metabolic rate. Neurological manifestations may be transient or permanent, and may range from cognitive dysfunction, cerebellar ataxia, Parkinsonism, sensorimotor neuropathy and autonomic dysfunction to neuromuscular junction disorders. This study attempts to provide a review of the major outbreaks of occupational neurotoxins from 1968 to 2012. A total of 16 occupational neurotoxins, including organophosphates, toxic gases, heavy metals, organic solvents, and other toxic chemicals, were reviewed. Peer-reviewed articles related to the electrophysiology, neuroimaging, treatment and long-term follow up of these neurotoxic diseases were also obtained. The heavy metals involved consisted of lead, manganese, organic tin, mercury, arsenic, and thallium. The organic solvents included n-hexane, toluene, mixed solvents and carbon disulfide. Toxic gases such as carbon monoxide, and hydrogen sulfide were also included, along with toxic chemicals including polychlorinated biphenyls, tetramethylammonium hydroxide, organophosphates, and dimethylamine borane. In addition we attempted to correlate these events to the timeline of industrial development in Taiwan. By researching this topic, the hope is that it may help other developing countries to improve industrial hygiene and promote occupational safety and health care during the process of industrialization.

What is the methodological principle of ChIA-PET?

Chromatin interaction analysis with paired-end tag sequencing (ChIA-PET) is a new technology to study genome-wide long-range chromatin interactions bound by protein factors. To minimize non-specific noise and reduce complexity, as well as to increase the specificity of the chromatin interaction analysis, chromatin immunoprecipitation (ChIP) is used against specific protein factors to enrich chromatin fragments of interest before proximity ligation. Combining Chromatin Immunoprecipitation (ChIP), proximity ligation and high-throughput sequencing, ChIA-PET provides a global and unbiased interrogation of higher-order chromatin structures associated with specific protein factors. Here, we propose a statistical model taking into account the genomic distance relationship, as well as the general propensity of anchors to be involved in contacts overall.

Genomes are organized into three-dimensional structures, adopting higher-order conformations inside the micron-sized nuclear spaces (7, 2, 12). Such architectures are not random and involve interactions between gene promoters and regulatory elements (13). The binding of transcription factors to specific regulatory sequences brings about a network of transcription regulation and coordination (1, 14). Chromatin Interaction Analysis by Paired-End Tag Sequencing (ChIA-PET) was developed to identify these higher-order chromatin structures (5,6). Cells are fixed and interacting loci are captured by covalent DNA-protein cross-links. To minimize non-specific noise and reduce complexity, as well as to increase the specificity of the chromatin interaction analysis, chromatin immunoprecipitation (ChIP) is used against specific protein factors to enrich chromatin fragments of interest before proximity ligation. Ligation involving half-linkers subsequently forms covalent links between pairs of DNA fragments tethered together within individual chromatin complexes. The flanking MmeI restriction enzyme sites in the half-linkers allow extraction of paired end tag-linker-tag constructs (PETs) upon MmeI digestion. As the half-linkers are biotinylated, these PET constructs are purified using streptavidin-magnetic beads. The purified PETs are ligated with next-generation sequencing adaptors and a catalog of interacting fragments is generated via next-generation sequencers such as the Illumina Genome Analyzer. Mapping and bioinformatics analysis is then performed to identify ChIP-enriched binding sites and ChIP-enriched chromatin interactions (8). We have produced a video to demonstrate critical aspects of the ChIA-PET protocol, especially the preparation of ChIP as the quality of ChIP plays a major role in the outcome of a ChIA-PET library. As the protocols are very long, only the critical steps are shown in the video. Since Jacob and Monod's characterization of the role of DNA elements in gene control, it has been recognized that the linear organization of genome structure is important for the regulation of gene transcription and hence the manifestation of phenotypes. Similarly, it has long been hypothesized that the spatial organization (in three dimensions evolving through time), as part of the epigenome, makes a significant contribution to the genotype-phenotype transition. Proximity ligation assays commonly known as chromosome conformation capture (3C) and 3C based methodologies (e.g., GCC, HiC and ChIA-Pet) are increasingly being incorporated into empirical studies to investigate the role that three-dimensional genome structure plays in the regulation of phenotype. The apparent simplicity of these methodologies-crosslink chromatin, digest, dilute, ligate, detect interactions-belies the complexity of the data and the considerations that should be taken into account to ensure the generation and accurate interpretation of reliable data. Here we discuss the probabilistic nature of these methodologies and how this contributes to their endogenous limitations. Identification of three-dimensional (3D) interactions between regulatory elements across the genome is crucial to unravel the complex regulatory machinery that orchestrates proliferation and differentiation of cells. ChIA-PET is a novel method to identify such interactions, where physical contacts between regions bound by a specific protein are quantified using next-generation sequencing. However, determining the significance of the observed interaction frequencies in such datasets is challenging, and few methods have been proposed. Despite the fact that regions that are close in linear genomic distance have a much higher tendency to interact by chance, no methods to date are capable of taking such dependency into account. Here, we propose a statistical model taking into account the genomic distance relationship, as well as the general propensity of anchors to be involved in contacts overall. Using both real and simulated data, we show that the previously proposed statistical test, based on Fisher's exact test, leads to invalid results when data are dependent on genomic distance. We also evaluate our method on previously validated cell-line specific and constitutive 3D interactions, and show that relevant interactions are significant, while avoiding over-estimating the significance of short nearby interactions. BACKGROUND: Long-range chromatin interactions play an important role in transcription regulation. Chromatin Interaction Analysis with Paired-End-Tag sequencing (ChIA-PET) is an emerging technology that has unique advantages in chromatin interaction analysis, and thus provides insight into the study of transcription regulation. RESULTS: This article introduces the experimental protocol and data analysis process of ChIA-PET, as well as discusses some applications using this technology. It also unveils the direction of future studies based on this technology. CONCLUSIONS: Overall we show that ChIA-PET is the cornerstone to explore the three-dimensional (3D) chromatin structure, and certainly will lead the forthcoming wave of 3D genomics studies.

Is there an association between borna virus and brain tumor?

There is no data to suggest an association between borna virus and brain tumor. Borna disease virus establishes a persistent infection in the central nervous system of vertebrate animal species as well as in tissue cultures causing cellular damage. Infected neural cells, include astrocytes, neurons, oligodendroglioma cell line. Borna disease virus replicates and can cause damage of brain cells.

We have used the reverse transcriptase-polymerase chain reaction technique to gain insight into the pathogenesis of encephalitis caused by Borna disease virus (BDV). RNA specific for BDV was first detected in the olfactory bulb of intranasally infected rats at 6 days postinfection (p.i.). At 14 days p.i., high levels of BDV RNA were found in all brain regions, and at 26 days p.i., BDV-specific RNA was also present in the eye, nasal mucosa, and facial skin. In the chronic phase of the disease, BDV RNA was identified in many peripheral organs but not in blood. Analysis of brain tissue for the presence of cytokine mRNAs revealed that the mRNA levels of interleukin-6 (IL-6), tumor necrosis factor alpha, and IL-1 alpha had increased sharply at 14 and 26 days p.i. These cytokine mRNAs reached maximum levels at the peak of inflammatory reactions and decreased drastically in the chronic phase of the disease. Although IL-2 mRNA was also found in normal brain, it was markedly increased in BDV-infected brain at 14 days p.i. Expression of gamma interferon (IFN-gamma) mRNA, which was not observed in normal rat brain, was detected at 14 days p.i. and reached a maximum level at 38 days p.i. IL-2 and IFN-gamma mRNA expression correlated with expression of CD4 and CD8 mRNAs, indicating that both CD4+ and CD8+ T lymphocytes are induced in the early stages of BDV infection. Since IFN-gamma and CD8 mRNA levels were still highly elevated in the chronic phase of Borna disease, it is likely that CD8+ T lymphocytes act to reduce inflammation and to ameliorate neurological signs during the chronic phase of infection. Borna disease is a rare but severe neurological disease of horses and sheep. Borna disease virus (BDV) has not been fully characterized because cell-free virus has not been isolated. Homogenates of infected brain are infectious both for animals and for some cell lines in culture. We report here the partial purification and characterization of cell-free BDV from the tissue culture supernatant of infected human neuroblastoma SKNSH cells. A single negative strand 10-kb RNA was detected in purified virions. Immunoprecipitation analysis of the BDV proteins in purified virions shows the presence of the 60-, 38-, 24-, and 14-kDa proteins previously identified as BDV-specific proteins in infected cells. Immune cells invading the central nervous system (CNS) in response to Borna disease virus (BDV) antigens are central to the pathogenesis of Borna disease (BD). We speculate that the response of the resident cells of the brain to infection may be involved in the sensitization and recruitment of these inflammatory cells. To separate the responses of resident cells from those of cells infiltrating from the periphery, we used dexamethasone to inhibit inflammatory reactions in BD. Treatment with dexamethasone prevented the development of clinical signs of BD, and the brains of treated animals showed no neuropathological lesions and a virtual absence of markers of inflammation, cell infiltration, or activation normally seen in the CNS of BDV-infected rats. In contrast, treatment with dexamethasone exacerbated the expression of BDV RNA, which was paralleled by a similarly elevated expression of mRNAs for egr-1, c-fos, and c-jun. Furthermore, dexamethasone failed to inhibit the increase in expression of mRNAs for tumor necrosis factor alpha, macrophage inflammatory protein 1 beta, interleukin 6, and mob-1, which occurs in the CNS of animals infected with BDV. Our findings suggest that these genes, encoding transcription factors, chemokines, and proinflammatory cytokines, might be directly activated in CNS resident cells by BDV. This result supports the hypothesis that the initial phase of the inflammatory response to BDV infection in the brain may be dependent upon virus-induced activation of CNS resident cells. Borna disease virus (BDV) causes central nervous system (CNS) disease in several vertebrate species, which is frequently accompanied by behavioral abnormalities. In the adult rat, intracerebral (i.c.) BDV infection leads to immunomediated meningoencephalitis. In contrast, i.c. infection of neonates causes a persistent infection in the absence of overt signs of brain inflammation. These rats (designated PTI-NB) display distinct behavioral and neurodevelopmental abnormalities. However, the molecular mechanisms for these virally induced CNS disturbances are unknown. Cytokines play an important role in CNS function, both under normal physiological and pathological conditions. Astrocytes and microglia are the primary resident cells of the central nervous system with the capacity to produce cytokines. Strong reactive astrocytosis is observed in the PTI-NB rat brain. We have used a ribonuclease protection assay to investigate the mRNA expression levels of proinflammatory cytokines in different brain regions of PTI-NB and control rats. We show here evidence of a chronic upregulation of proinflammatory cytokines interleukin-6, tumor necrosis factor alpha, interleukins-1alpha, and -1beta in the hippocampus and cerebellum of the PTI-NB rat brain. These brain regions exhibited only a very mild and transient immune infiltration. In contrast, in addition to reactive astrocytes, a strong and sustained microgliosis was observed in the PTI-NB rat brains. Our data suggest that CNS resident cells, namely astrocytes and microglia, are the major source of cytokine expression in the PTI-NB rat brain. The possible implications of these findings are discussed. Perinatal exposure to infectious agents and toxins is linked to the pathogenesis of neuropsychiatric disorders, but the mechanisms by which environmental triggers interact with developing immune and neural elements to create neurodevelopmental disturbances are poorly understood. We describe a model for investigating disorders of central nervous system development based on neonatal rat infection with Borna disease virus, a neurotropic noncytolytic RNA virus. Infection results in abnormal righting reflexes, hyperactivity, inhibition of open-field exploration, and stereotypic behaviors. Architecture is markedly disrupted in hippocampus and cerebellum, with reduction in granule and Purkinje cell numbers. Neurons are lost predomitly by apoptosis, as supported by increased mRNA levels for pro-apoptotic products (Fas, caspase-1), decreased mRNA levels for the anti-apoptotic bcl-x, and in situ labeling of fragmented DNA. Although inflammatory infiltrates are observed transiently in frontal cortex, glial activation (microgliosis > astrocytosis) is prominent throughout the brain and persists for several weeks in concert with increased levels of proinflammatory cytokine mRNAs (interleukins 1alpha, 1beta, and 6 and tumor necrosis factor alpha) and progressive hippocampal and cerebellar damage. The resemblance of these functional and neuropathologic abnormalities to human neurodevelopmental disorders suggests the utility of this model for defining cellular, biochemical, histologic, and functional outcomes of interactions of environmental influences with the developing central nervous system. Borna disease virus (BDV) is a nonsegmented negative-strand RNA virus that belongs to the Mononegavirales. Unlike other animal viruses of this order, BDV replicates and transcribes in the nucleus of infected cells. Previous studies have shown that BDV uses RNA splicing machinery for its mRNA expression. In the present study, we identified spliced RNAs that use an alternative 3' splice site, SA3, in BDV-infected cell lines as well as infected animal brain cells. Transient transfection analysis of cDNA clones of BDV RNA revealed that although SA3 is a favorable splice site in mammalian cells, utilization of SA3 is negatively regulated in infected cells. This negative splicing activity of the SA3 site is regulated by a putative cis-acting region, the exon splicing suppressor (ESS), within the polymerase exon of BDV. The BDV ESS contains similar motifs to other known ESSs present in viral and cellular genes. Furthermore, our results indicated that a functional polyadenylation signal just upstream of the BDV ESS is also involved in the regulation of alternative splicing of BDV. These observations represent the first documentation of complex RNA splicing in animal RNA viruses and also provide new insight into the mechanism of regulation of alternative splicing in animal viruses. To investigate the biological characteristics of field isolates of Borna disease virus (BDV), as well as to understand BDV infections outside endemic countries, we isolated the virus from brain samples of a heifer with Borna disease in Japan. We demonstrate that the brain lysate contained replication products of BDV and induced viral propagation in rat glioma cells, suggesting that a replication-competent BDV existed in the bovine brain. This field strain of BDV, named Bo/04w, showed efficient viral release and transmissibility and also displayed a distinct pattern of expression of viral phosphoprotein (P) during infection, as compared with laboratory-adapted BDV strains. Interestingly, we found the level of P to be significantly low in cells infected with Bo/04w, and the transcription of this isolate to be more efficient than that of laboratory strain of BDV. These results indicated that the field isolate may regulate the expression of P at an optimal level in infected cells. We also confirmed that Bo/04w maintains biological significance in neonatal gerbil brain. Sequencing revealed that despite the biological differences, the field isolate is closely related genetically to the laboratory strains of BDV. We discuss here the sequence similarities between BDV isolates from endemic and nonendemic countries. Borna disease virus (BDV), a nonsegmented, negative-strand RNA virus, infects a wide variety of mammalian species and readily establishes a long-lasting, persistent infection in brain cells. Therefore, this virus could be a promising candidate as a novel RNA virus vector enabling stable gene expression in the central nervous system (CNS). Previous studies demonstrated that the 5' untranslated region of the genome is the only site for insertion and expression of a foreign gene. In this study, we established a novel BDV vector in which an additional transcription cassette has been inserted into an intercistronic noncoding region between the viral phosphoprotein (P) and matrix (M) genes. The recombit BDV (rBDV) carrying green fluorescent protein (GFP) between the P and M genes, rBDV P/M-GFP, expressed GFP efficiently in cultured cells and rodent brains for a long period of time without attenuation. Furthermore, we generated a nonpropagating rBDV, ΔGLLP/M, which lacks the envelope glycoprotein (G) and a splicing intron within the polymerase gene (L), by the transcomplementation system with either transient or stable expression of the G gene. Interestingly, rBDV ΔGLLP/M established a persistent infection in cultured cells with stable expression of GFP in the absence of the expression of G. Using persistently infected rBDV ΔGLLP/M-infected cells, we determined the amino acid region in the cytoplasmic tail (CT) of BDV G important for the release of infectious rBDV particles and also demonstrated that the CT region may be critical for the generation of pseudotyped rBDV having vesicular stomatitis virus G protein. Our results revealed that the newly established BDV vector constitutes an alternative tool not only for stable expression of foreign genes in the CNS but also for understanding the mechanism of the release of enveloped virions. Proinflammatory state of the brain increases the risk for seizure development. Neonatal Borna disease virus (BDV)-infection of mice with neuronal overexpression of tumor necrosis factor-α (TNF) was used to investigate the complex relationship between enhanced cytokine levels, neurotropic virus infection and reaction pattern of brain cells focusing on its role for seizure induction. Viral antigen and glial markers were visualized by immunohistochemistry. Different levels of TNF in the CNS were provided by the use of heterozygous and homozygous TNF overexpressing mice. Transgenic TNF, total TNF (native and transgenic), TNF-receptor (TNFR1, TNFR2), IL-1 and N-methyl-D-aspartate (NMDA)-receptor subunit 2B (NR2B) mRNA values were measured by real time RT-PCR. BDV-infection of TNF-transgenic mice resulted in non-purulent meningoencephalitis accompanied by epileptic seizures with a higher frequency in homozygous animals. This correlated with lower weight gain, stronger degree and progression of encephalitis and early, strong microglia activation in the TNF-transgenic mice, most obviously in homozygous animals. Activation of astroglia could be more intense and associated with an unusual hypertrophy in the transgenic mice. BDV-antigen distribution and infectivity in the CNS was comparable in TNF-transgenic and wild-type animals. Transgenic TNF mRNA-expression was restricted to forebrain regions as the transgene construct comprised the promoter of NMDA-receptor subunit2B and induced up-regulation of native TNF mRNA. Total TNF mRNA levels did not increase significantly after BDV-infection in the brain of transgenic mice but TNFR1, TNFR2 and IL-1 mRNA values, mainly in the TNF overexpressing brain areas. NR2B mRNA levels were not influenced by transgene expression or BDV-infection. Neuronal TNF-overexpression combined with BDV-infection leads to cytokine up-regulation, CNS inflammation and glial cell activation and confirmed the presensitizing effect of elevated cytokine levels for the development of spontaneous epileptic seizures when exposed to additional infectious noxi.

List medication interfering with purine metabolism that are used for treatment of T-cell prolymphocytic leukemia?

Deoxycoformycin and pentostatin are purine analogs that interfere with purine metabolism and are used for treatment of T-cell prolymphocytic leukemia patients.

BACKGROUND: B-cell prolymphocytic leukemias or T-cell prolymphocytic leukemias are aggressive variants of chronic lymphoid leukemias. The small studies conducted to date have shown median survival durations of approximately 3 years for patients who have B-cell prolymphocytic leukemia and 7.5 months for those who have T-cell prolymphocytic leukemia, compared with about 8 years for patients who have chronic lymphocytic leukemia. In chronic lymphocytic leukemia, chemotherapy consisting of alkylating agents such as cyclophosphamide and chlorambucil combined with prednisone has achieved overall response rates of 50% to 70%, but this regimen has resulted in response rates of less than 25% in prolymphocytic leukemia. Pentostatin (2'-deoxycoformycin; DCF) is a purine analogue that has shown activity in treatment of chronic lymphoid maligcies. PURPOSE: This prospective phase II trial by the Leukemia Cooperative Group of the European Organization for Research and Treatment of Cancer was performed to assess the activity and toxicity of DCF in prolymphocytic leukemia. METHODS: Twenty patients with B-cell or T-cell prolymphocytic leukemia were given DCF at a dosage of 4 mg/m2 intravenously once a week for 3 weeks, then every other week for three doses. Patients who had at least partial response received maintece therapy once a month for a maximum of 6 months. Fourteen patients had B-cell prolymphocytic leukemia, and six had T-cell prolymphocytic leukemia, as evidenced by morphologic and immunologic criteria; three were previously untreated, eight had been given one or two chemotherapeutic regimens, and nine had been given more than two. RESULTS: One patient died of an unknown cause during the first 6 weeks of treatment, and one died of disseminated toxoplasmosis during the period of maintece therapy, 5 months after achieving partial remission. Nine (45% response rate) of the 20 patients achieved partial remission, including seven (50%) of 14 with B-cell prolymphocytic leukemia and two (33%) of six with T-cell prolymphocytic leukemia. The median duration of response was 9 months (range, 2-30 months); for patients with B-cell prolymphocytic leukemia, the median remission duration was 12 months. No complete remission was observed. Toxic effects included nausea and vomiting (30%), infections (30%), and transient increase in liver enzymes (35%) and in creatinine (20%) levels. Eight patients experienced thrombocytopenia, the major hematologic toxic effect; four had grade 3 or 4 toxic effects. CONCLUSION: DCF is active in prolymphocytic leukemia, even as salvage therapy in patients who had received multiple prior chemotherapeutic regimens. IMPLICATIONS: Trials using DCF or other purine analogues alone or in combination with standard chemotherapeutic agents in front-line or salvage therapy are warranted to improve the prognosis of patients with prolymphocytic leukemia. PURPOSE: T-prolymphocytic leukemia (T-PLL) is an aggressive maligcy of mature T cells refractory to conventional chemotherapy, with a median survival duration of 7.5 months. We report here promising results with the use of a genetically reshaped human CD52 antibody, CAMPATH-1H. PATIENTS AND METHODS: Fifteen patients with T-PLL, most of whom had received the purine analog deoxycoformycin (DCF), were treated with CAMPATH-1H. Results were compared with those of 25 patients treated with DCF. RESULTS: Major responses occurred in 11 patients (73%) treated with CAMPATH-1H compared with 40% with DCF. Complete remissions (CRs) were documented in nine (60%) of the CAMPATH-1H cases and only three (12%) were obtained with DCF. CRs with CAMPATH-1H were durable, and re-treatment with the antibody resulted in second CRs in three relapsed patients. Two of them were successfully autografted with peripheral-blood and bone marrow stem cells collected during the first CR. Apart from first-dose reactions, infusions of CAMPATH-1H were well tolerated. However, two responding patients developed severe bone marrow aplasia that was fatal in one; the second remained moderately pancytopenic 21 weeks after stopping CAMPATH-1H therapy. The cause of this adverse effect is unknown. CONCLUSION: CAMPATH-1H is an effective agent in T-PLL and represents a significant improvement over other types of therapy. However, CAMPATH-1H alone is not sufficient for long-term remissions, and the role of autologous stem-cell transplantation needs further investigation. Prolymphocytic leukemia is a rare chronic lymphoproliferative disorder that includes two subtypes, B cell and T cell, each with its own distinct clinical, laboratory and pathological features. T-cell prolymphocytic leukemia has an aggressive course with short median survival and poor response to chemotherapy. With the use of the purine analogue pentostatin more than half of patients will have a major response and a minority will have a complete remission, usually lasting months. With the introduction of alemtuzumab, most patients who progressed despite treatment with pentostatin had a major response with a complete remission rate higher than that obtained with pentostatin when used as a first line. Unfortunately, progression still follows shortly. We recommend alemtuzumab as initial therapy and offer stem cell transplant (SCT) to selected young, healthy patients who respond. Although B-cell prolymphocytic leukemia is also a progressive disease, some patients can achieve a prolonged progression-free-survival with fludarabine. Patients presenting with massive splenomegaly may be effectively palliated with splenic irradiation or splenectomy. Rituximab is a promising agent and further investigations are warranted to better define its role in treatment of this disorder. Alemtuzumab is an immunosuppressive antibody that depletes normal T cells and B cells. Prophylaxis for herpes virus and Pneumocystis carinii is standard with this agent. Approximately 20% to 25% of patients will experience cytomegalovirus (CMV) reactivation. We conducted a randomized trial wherein patients being treated with an alemtuzumab-containing regimen received prophylaxis with either valaciclovir 500 mg orally daily or valganciclovir 450 mg orally twice daily. The study design planned to enroll 128 patients, but stopping rules for early termination were met. Forty patients were evaluable. Median age was 58 years (range, 25-83 years); median number of prior therapies was 2 (range, 0-10). Diagnoses included chronic lymphocytic leukemia (29), T-cell prolymphocytic leukemia (3), hairy cell leukemia (1), adult T-cell leukemia/lymphoma (ATLL) (1), marginal zone leukemia (1), large granular lymphocyte leukemia (2), acute lymphoblastic leukemia (1), and T-cell lymphoma (2). Patients received various alemtuzumab-containing regimens, including single agent (5) or combined with: rituximab (2), pentostatin (6), fludarabine, cyclophosphamide, and rituximab (23), or fractionated cyclophosphamide, vincristine, adriamycin, and dexamethasone (hyper-CVAD) (4). Seven of 20 patients enrolled on the valaciclovir arm experienced CMV reactivation. None of the 20 patients randomized to valganciclovir experienced CMV reactivation (P = .004). In conclusion, this agent was highly effective for prophylaxis of CMV reactivation in patients receiving alemtuzumab. This trial was registered at www.ClinicalTrials.gov as #NCT00562770. PURPOSE: To test whether nelarabine is an effective agent for indolent leukemias and to evaluate whether there is a relationship between cellular pharmacokinetics of the analog triphosphate and clinical responses. PATIENTS AND METHODS: Thirty-five patients with relapsed/refractory leukemias (n = 24, B-cell chronic lymphocytic leukemia and n = 11, T-cell prolymphocytic leukemia) were entered onto three different protocols. For schedule A, patient received nelarabine daily for 5 days, whereas for schedule B, nelarabine was administered on days 1, 3, and 5. Schedule C was similar to schedule B except that fludarabine was also infused. Plasma and cellular pharmacokinetics were studied during the first cycle. RESULTS: Responses were achieved in 20%, 15%, and 63% of patients receiving schedule A, B, and C, respectively. Histologic category, number of prior therapies, and fludarabine refractoriness did not influence the response rate. The most common nonhematologic toxicity was peripheral neuropathy. Grade 4 neutropenia and thrombocytopenia complicated 23% and 26% of courses respectively, and were significantly more frequent among patients with pre-existing marrow failure. Pharmacokinetics of plasma nelarabine and arabinosylguanine (ara-G) and of cellular ara-G triphosphate (ara-GTP) were similar in the two groups of diagnoses, and the elimination of ara-GTP from leukemia cells was slow (median, > 24 hours). The median peak intracellular concentrations of ara-GTP were significantly different (P = .0003) between responders (440 micromol/L; range, 35 to 1,438 micromol/L; n = 10) and nonresponders (50 micromol/L; range, 22 to 178 micromol/L; n = 15). CONCLUSION: Nelarabine is an effective regimen against indolent leukemias, and combining it with fludarabine was most promising. Determination of tumor cell ara-GTP levels may provide a predictive test for response to nelarabine. T-cell prolymphocytic leukemia is a rare post-thymic lymphoid disorder, which has distinctive clinical, morphologic, immunophenotypic and cytogenetic features. It has previously been associated with an aggressive course, poor response to conventional chemotherapy and a short median survival. Treatment with purine analogs and the monoclonal antibody alemtuzumab has resulted in significantly higher response rates and increased survival. However, responses are transient and allogeneic hematopoietic progenitor-cell transplantation remains the only potential curative option. The proportion of patients eligible for transplant is low, owing to the older age group of patients, and nonmyeloablative transplantation is a promising alternative that needs to be explored. Rarer chronic lymphoid leukaemias represent a challenge to the clinicians due to the limited information on their pathogenesis, difficulties on setting up prospective clinical trials and to their refractoriness to drugs used in the most common form of chronic lymphocytic leukaemia (CLL). In this review all these issues are addressed in three B-cell leukaemias: B-cell prolymphocytic leukaemia (B-PLL), hairy cell leukaemia (HCL) and HCL-variant and three T-cell leukaemias: T-cell prolymphocytic leukaemia (T-PLL), T-cell large granular lymphocytic leukaemia (T-cell LGLL) and adult T-cell leukaemia lymphoma (ATLL). Data will be presented on the natural history, current therapies and emerging drugs potentially useful in the treatment of patients with these leukaemias. Emphasis is made on: 1- the novel agents targeting a variety of B and T-cell antigens expressed on the surface of the leukaemic cells; these are either unconjugated monoclonal antibodies (McAb) such as Rituximab (anti-CD20), the second and third generation of anti-CD20 McAbs, Alemtuzumab (anti-CD52), Siplizumab (anti-CD2), Daclizumab (anti-CD25) and KW-0761, an anti-chemokine receptor 4 (CCR4) or McAbs conjugated to toxins such as CD22 linked to the pseudomonas exotoxin or radiolabelled McAb; 2- the use of new purine nucleosides such as nelarabine and 3- agents targeting deregulated genes in the leukaemic cells from these diseases such as the Poly (ADP-ribose) polymerase (PARP) Olarapib in T-PLL with deregulation of the ataxia telangiectasia mutated (ATM) gene. Data of phase I and II clinical studies with these agents as well as the potential and current use of other drugs are outlined. BACKGROUND: Scarce systematic trial data have prevented uniform therapeutic guidelines for T-cell prolymphocytic leukemia (T-PLL). A central need in this historically refractory tumor is the controlled evaluation of multiagent chemotherapy and its combination with the currently most active single agent, alemtuzumab. METHODS: This prospective multicenter phase 2 trial assessed response, survival, and toxicity of a novel regimen in previously treated (n = 9) and treatment-naive (n = 16) patients with T-PLL. Induction by fludarabine, mitoxantrone, and cyclophosphamide (FMC), for up to 4 cycles, was followed by alemtuzumab (A) consolidation, up to 12 weeks. RESULTS: Of the 25 patients treated with FMC, 21 subsequently received alemtuzumab. Overall response rate to FMC was 68%, comprising 6 complete remissions (all bone-marrow confirmed) and 11 partial remissions. Alemtuzumab consolidation increased the intent-to-treat overall response rate to 92% (12 complete remissions; 11 partial remissions). Median overall survival after FMC-A was 17.1 months and median progression-free survival was 11.9 months. Progression-free survival tended to be shorter for patients with high-level T-cell leukemia 1 oncoprotein expression. Hematologic toxicities were the most frequent grade 3/4 side effects under FMC-A. Exclusively in the 21 alemtuzumab-consolidated patients, 13 cytomegalovirus reactivations were observed; 9 of these 13 represented a clinically relevant infection. CONCLUSIONS: FMC-A is a safe and efficient protocol in T-PLL, which compares favorably to published data.

Does PU.1 (SPI1) affect NF-kB binding?

Recent data demonstrate that developmental transcription factors like the macrophage fate-determining Pu.1 set the stage for the activity of ubiquitous transcription factors activated by inflammatory stimuli, like NF-kB, AP-1, and interferon regulatory factors (IRFs). Within 1217 bp of upstream sequence, 3 sites for NF-kB, 10 sites for NF-IL6, 15 sites for AP1, 6 sites for AP4, 2 sites for CHOP/CEBP alpha and 1 site for SP1 and PU.1 were identified.

The leukocyte integrin p150,95 (CD11c/CD18) is involved in a number of cell-cell and cell-extracellular matrix interactions and mediates signal transduction into the cytoplasm. p150,95 is expressed on cells of the myeloid lineage as well as on certain activated T and B lymphocytes, and its expression is regulated during cell activation and differentiation. Since CD18 is expressed on all leukocyte lineages, the restricted expression of p150,95 must be controlled at the level of CD11c gene transcription. To understand the mechanisms that direct the constitutive and regulated leukocyte expression of p150,95 we have structurally characterized the CD11c promoter region and initiated its functional dissection. The CD11c promoter lacks TATA- and CCAAT-boxes, directs the synthesis of transcripts with heterogeneous 5'-ends, and contains an initiator-like sequence at the major transcription initiation site. Several putative binding sequences for ubiquitous (Sp1, AP-1, AP-2, and NF-kB) and leukocyte-specific (PU.1) transcription factors have been identified in the proximal region of the CD11c promoter which may participate in the regulation of the expression of p150,95. Transient expression of CD11c-based reporter gene constructs indicates that the CD11c promoter dictates the tissue-specific expression of p150,95 and that sequences contained within 160 base pairs 5' from the major transcriptional start site are involved in the tissue-specific and regulated expression of p150,95. DNase I protection analysis on the promoter region spanning from -160 to +40 revealed four regions of DNA-protein interactions (FPI-FPIV), two of which (FPII and FPIV) correlate with the cell type-specific and regulated expression of the CD11c gene. Large conductance, calcium-activated potassium (maxiK) channels are expressed in nerve, muscle, and other cell types and are important determits of smooth muscle tone. To determine the mechanisms involved in the transcriptional regulation of maxiK channels, we characterized the promoter regions of the pore forming (alpha) and regulatory (beta) subunits of the human channel complex. Maximum promoter activity (up to 12.3-fold over control) occurred between nucleotides -567 and -220 for the alpha subunit (hSlo) gene. The minimal promoter is GC-rich with 5 Sp-1 binding sites and several TCC repeats. Other transcription factor-binding motifs, including c/EBP, NF-kB, PU.1, PEA-3, Myo-D, and E2A, were observed in the 5'-flanking sequence. Additionally, a CCTCCC sequence, which increases the transcriptional activity of the SM1/2 gene in smooth muscle, is located 27 bp upstream of the TATA-like sequence, a location identical to that found in the SM1/2 5'-flanking region. However, the promoter directed equivalent expression when transfected into smooth muscle and other cell types. Analysis of the hSlo beta subunit 5'-flanking region revealed a TATA box at position -77 and maximum promoter activity (up to 11.0-fold) in a 200 bp region upstream from the cap site. Binding sites for GATA-1, Myo-D, c-myb, Ets-1/Elk-1, Ap-1, and Ik-2 were identified within this sequence. Two CCTCCC elements are present in the hSlo beta subunit promoter, but tissue-specific transcriptional activity was not observed. The lack of tissue-specific promoter activity, particularly the finding of promoter activity in cells from tissues in which the maxiK gene is not expressed, suggests a complex channel regulatory mechanism for hSlo genes. Moreover, the lack of similarity of the promoters of the two genes suggests that regulation of coordinate expression of the subunits does not occur through equivalent cis-acting sequences. The majority of patients with acute myeloid leukemia (AML) still die of their disease, and novel therapeutic concepts are needed. Timely expression of the hematopoietic master regulator PU.1 is crucial for normal development of myeloid and lymphoid cells. Targeted disruption of an upstream regulatory element (URE) located several kb upstream in the PU.1 promoter decreases PU.1 expression thereby inducing AML in mice. In addition, suppression of PU.1 has been observed in specific subtypes of human AML. Here, we identified nuclear factor-kappaB (NF-kappaB) to activate PU.1 expression through a novel site within the URE. We found sequence variations of this particular NF-kappaB site in 4 of 120 AML patients. These variant NF-kappaB sequences failed to mediate activation of PU.1. Moreover, the synergistic activation of PU.1 together with CEBPB through these variant sequences was also lost. Finally, AML patients with such variant sequences had suppressed PU.1 mRNA expression. This study suggests that changes of a single base pair in a distal element critically affect the regulation of the tumor suppressor gene PU.1 thereby contributing to the development of AML. Inflammation involves the activation of a highly coordinated gene expression program that is specific for the initial stimulus and occurs in a different manner in bystander parenchymal cells and professional immune system cells recruited to the inflamed site. Recent data demonstrate that developmental transcription factors like the macrophage fate-determining Pu.1 set the stage for the activity of ubiquitous transcription factors activated by inflammatory stimuli, like NF-kB, AP-1, and interferon regulatory factors (IRFs). The intersection of lineage-determining and stimulus-activated transcription factors at enhancers explains cell type specificity in inflammatory responses.

Does the majority of the mitochondrial genomes abide to the second parity rule (PR2)?

A large number of mitochondrial genomes significantly deviate from the 2nd parity rule, in contrast to the eubacterial ones. This behaviour of the large majority of the mitochondrial genomes may be attributed to their distinct mode of replication, which is fundamentally different from the one of the eubacteria.

Based on 152 mitochondrial genomes and 36 bacterial chromosomes that have been completely sequenced, as well as three long contigs for human chromosomes 6, 21, and 22, we examined skews of mononucleotide frequencies and the relative abundance of dinucleotides in one DNA strand. Each group of these genomes has its own characteristics. Regarding mitochondrial genomes, both CpG and GpT are underrepresented, while either GpG or CpC or both are overrepresented. The relative frequency of nucleotide T vs A and of nucleotide G vs C is strongly skewed, due presumably to strand asymmetry in replication errors and unidirectional DNA replication from single origins. Exceptions are found in the plant and yeast mitochondrial genomes, each of which may replicate from multiple origins. Regarding bacterial genomes, the "universal" rule of CpG deficiency is restricted to archaebacteria and some eubacteria. In other eubacteria, the most underrepresented dinucleotide is either TpA or GpT. In general, there are significant T vs A and G vs C skews in each half of the bacterial genome, although these are almost exactly canceled out over the whole genome. Regarding human chromosomes 6, 21, and 22, dinucleotide CpG tends to be avoided. The relative frequency of mononucleotides exhibits conspicuous local skews, suggesting that each of these chromosomal segments contains more than one DNA replication origin. It is concluded that, when there are several replicons in a genomic region, not only the number of DNA replication origins but also the directionality is important and that the observed patterns of nucleotide frequencies in the genome strongly support the hypothesis of strand asymmetry in replication errors.

What is the association between h-index and academic rank in academic neurosurgery?

Greater h-index is associated with greater academic rank in academic neurosurgery. The h indices increased significantly with increasing academic rank, with the median for instructors, assistant professors, associate professors, and professors was shown to be 2, 5, 10, and 19, respectively. In addition, h-index was shown to be predictive of NIH funding, fellowship training, academic productivity and salary.

OBJECT: The authors undertook a study to estimate the relative academic impact of neurosurgical departments in Canada and the US using the h index, a measure of the number of citations received by a collection of work. METHODS: The study included 99 departments of neurosurgery with residency programs participating in the US National Residency Matching Program, and the 14 analogous Canadian programs. Three types of h indices were determined-one reflecting the cumulative work attributed to a neurosurgical department, h(c); one restricted to the cumulative work published over the past 10 years, h(10); and one limited to work published in 2 major North American neurosurgical journals, h(NS)(10). For an article to be included, attribution to a neurosurgical department had to appear in the address field in the database Thomson's ISI Web of Science. The three h indices were compared with each other, and their relation to other measures such as size of the department, degrees held by the faculty, and research funding was examined. RESULTS: Significant correlations were found between the citation indices and faculty size, number of publications and the types of degrees held by the faculty, and funding by the US NIH. Three types of authorship were identified: neurosurgeon, nonclinician researcher, and nonneurosurgeon clinical affiliate. The degree to which the latter 2 nonneurosurgeon categories contributed to the departmental h index varied among departments and can confound interdepartmental comparison. Limiting articles to those published in neurosurgical journals appeared to correct for the influence of nonneurosurgeons in departmental impact and reflect neurosurgeon-driven scholarship. CONCLUSIONS: The h index may be useful in evaluating output across neurosurgery departments. OBJECT: The h index is a recently developed bibliometric that assesses an investigator's scientific impact with a single number. It has rapidly gained popularity in the physical and, more recently, medical sciences. METHODS: The h index for all 1120 academic neurosurgeons working at all Electronic Residency Application Service-listed training programs was determined by reference to Google Scholar. A random subset of 100 individuals was investigated in PubMed to determine the total number of publications produced. RESULTS: The median h index was 9 (range 0-68), with the 75th, 90th, and 95th percentiles being 17, 26, and 36, respectively. The h indices increased significantly with increasing academic rank, with the median for instructors, assistant professors, associate professors, and professors being 2, 5, 10, and 19, respectively (p < 0.0001, Kruskal-Wallis; all groups significantly different from each other except the difference between instructor and assistant professor [Conover]). Departmental chairs had a median h index of 22 (range 3-55) and program directors a median of 17 (range 0-62). Plot of the log of the rank versus h index demonstrated a remarkable linear pattern (R(2) = 0.995, p < 0.0001), suggesting that this is a power-law relationship. CONCLUSIONS: A survey of the h index for all of academic neurosurgery is presented. Results can be used for benchmark purposes. The distribution of the h index within an academic population is described for the first time and appears related to the ubiquitous power-law distribution. OBJECT: Factors determining choice of an academic career in neurological surgery are unclear. This study seeks to evaluate the graduates of medical schools and US residency programs to determine those programs that produce a high number of graduates remaining within academic programs and the contribution of these graduates to academic neurosurgery as determined by h-index valuation. METHODS: Biographical information from current faculty members of all accredited neurosurgery training programs in the US with departmental websites was obtained. Any individual who did not have an American Board of Neurological Surgery certificate (or was not board eligible) was excluded. The variables collected included medical school attended, residency program completed, and current academic rank. For each faculty member, Web of Science and Scopus h-indices were also collected. RESULTS: Ninety-seven academic neurosurgery departments with 986 faculty members were analyzed. All data regarding training program and medical school education were compiled and analyzed by center from which each faculty member graduated. The 20 medical schools and neurosurgical residency training programs producing the greatest number of graduates remaining in academic practice, and the respective individuals' h-indices, are reported. Medical school graduates of the Columbia University College of Physicians and Surgeons chose to enter academics the most frequently. The neurosurgery training program at the University of Pittsburgh produced the highest number of academic neurosurgeons in this sample. CONCLUSIONS: The use of quantitative measures to evaluate the academic productivity of medical school and residency graduates may provide objective measurements by which the subjective influence of training experiences on choice of an academic career may be inferred. The top 3 residency training programs were responsible for 10% of all academic neurosurgeons. The influence of medical school and residency experiences on choice of an academic career may be significant. Leaders of academic institutions evaluate academic productivity when deciding to hire, promote, or award resources. This study examined the distribution of the h-index, an assessment of academic standing, among radiation oncologists. The authors collected h-indices for 826 US academic radiation oncologists from a commercial bibliographic database (SCOPUS, Elsevier B.V., NL). Then, logarithmic transformation was performed on h-indices and ranked h-indices, and results were compared to estimates of a power law distribution. The h-index frequency distribution conformed to both the log-linear variation of a power law (r (2) = .99) and the beta distribution with the same fitting exponents as previously described in a power law analysis of the productivity of neurosurgeons. Within radiation oncology, as in neurosurgery, there are exceedingly more faculty with an h-index of 1-2. The distribution fitting the same variation of a power law within two fields suggests applicability to other areas of academia. BACKGROUND: The h-index is a commonly used metric for evaluating the publication performance of researchers. However, in a multidisciplinary field such as medical informatics, interpreting the h-index is a challenge because researchers tend to have diverse home disciplines, ranging from clinical areas to computer science, basic science, and the social sciences, each with different publication performance profiles. OBJECTIVE: To construct a reference standard for interpreting the h-index of medical informatics researchers based on the performance of their peers. METHODS: Using a sample of authors with articles published over the 5-year period 2006-2011 in the 2 top journals in medical informatics (as determined by impact factor), we computed their h-index using the Scopus database. Percentiles were computed to create a 6-level benchmark, similar in scheme to one used by the US National Science Foundation, and a 10-level benchmark. RESULTS: The 2 benchmarks can be used to place medical informatics researchers in an ordered category based on the performance of their peers. A validation exercise mapped the benchmark levels to the ranks of medical informatics academic faculty in the United States. The 10-level benchmark tracked academic rank better (with no ties) and is therefore more suitable for practical use. CONCLUSIONS: Our 10-level benchmark provides an objective basis to evaluate and compare the publication performance of medical informatics researchers with that of their peers using the h-index. OBJECT: Various bibliometric indices are now commonly used to assess academic productivity in medicine. Some evidence suggests that these measures are specific to subspecialty areas. The authors' goal was to measure the h index of academic pediatric neurosurgeons and compare it with previously reported results for academic neurosurgeons in general. METHODS: Programs with an Accreditation Council for Pediatric Neurosurgery Fellowships-approved fellowship were identified, and the h and g indices of each of their surgeons were calculated. These were correlated with academic rank and compared with published literature on academic neurosurgical departments. RESULTS: Seventy-two pediatric neurosurgeons had a mean h index of 16.6 and a mean g index of 29.5. Both indices increased with progressive academic rank. The rank-specific mean index for academic pediatric neurosurgeons was similar to that of neurosurgeons from academic departments in general. CONCLUSIONS: Overall, the authors conclude that the h index metric is a reasonable measure of academic productivity in the pediatric neurosurgery arena that provides a robust measure of an individual's contribution to the pediatric neurosurgery literature. Like its counterpart in neurosurgery in general, the h index for pediatric neurosurgeons correlates with institutional rank. The h index calculation also reveals the productivity of the pediatric neurosurgeons to be on par with the productivity of neurosurgeons in general. OBJECTIVE: The h-index was introduced as a means of quantifying the contribution a researcher makes to the scientific literature. We evaluated the h-index for academic neurosurgeons to assess the various methods of calculation and to determine whether the h-index can be used to differentiate groups of individuals by various classifications. METHODS: The h-index was calculated for all neurosurgeons from 10 institutions ranked highly by 2012 U.S. News & World Report plus the authors' institution via Scopus. The h-index also was calculated manually to evaluate its accuracy. The average h-index was calculated for groups on the basis of sex, academic rank, years in practice, institution, and subspecialty. Cumulative and mean h-indices were calculated for each department. RESULTS: The median h-index for the 188 neurosurgeons was 16 (mean, 19.71; range, 0-61). There was a positive association between the h-index, academic rank, and years posttraining. There was a significant difference between the "manually calculated" and automated h-indices, particularly for more senior physicians. The difference in h-index between men and women was not statistically significant. Among subspecialties, vascular surgeons had the greatest average h-index and general neurosurgeons had the lowest. There were significant shifts in departmental rankings when the cumulative or mean departmental indices were compared with the U.S. News & World Report rankings. CONCLUSION: Application of the h-index as a bibliometric in neurosurgery can distinguish academic productivity on the basis of academic rank, years posttraining, and neurosurgical subspecialties. The application of the h-index to compare departments is problematic and, at this time, not reliable. OBJECTIVE: The widely accepted h-index depends on the citation analysis source and does not consider the authorship position, the journal's impact factor (IF), or the age of the paper or author. We investigated these factors in citation statistics of academic neurosurgeons. METHODS: An uncorrected h-index and the m-quotient, which corrects for career length, were calculated by the use of Scopus and Google Scholar. In a subset of neurosurgeons, we computed the contemporary h-index (hc), which accounts for the age of the publications; the authorship value (AV), weighted by author position; and the journal IF. An "overall' average for AV and IF including most of an author's publications and an average for publications comprising the h-index ("h-index core") were calculated. RESULTS: When we used Google Scholar, the mean h-index was significantly greater than that calculated when we used Scopus (P = 0.0030). m-quotient and hc-index increased with academic rank, with an m-quotient >1 achieved by 69% of chairmen and 48% of professors. The effect of AV was greatest on the greater h-indices. The average IF for the h-index core was greater than the overall IF, which did not correlate with academic rank. Few neurosurgeons consistently publish in high-impact journals. CONCLUSION: Google Scholar tends to inflate the h-index. The m-quotient and hc-index allow comparisons of researchers across time. Although average journal IF did not differ significantly among neurosurgeons academic ranks, it should be noted for individuals who consistently publish in high-impact journals. We recommend the creation of individual bibliometric profiles to better compare the academic productivity of neurosurgeons. BACKGROUND: An increasing number of neurological surgeons have sought fellowship training in recent years, and previous analyses have suggested these practitioners are more likely to pursue an academic career. Scholarly productivity is a key component in academic advancement. OBJECTIVE: We used the h-index to evaluate whether fellowship training impacts research productivity and whether any differences exist in scholarly output among practitioners in the various neurosurgical subspecialties. METHODS: Online listings from academic neurological surgery departments were used to organize faculty by academic rank and fellowship training. Using the Scopus database, we calculated the h-index for 869 full-time clinical faculty. RESULTS: Mean h-index did not differ between fellowship- and nonfellowship-trained practitioners (h = 12.6 vs. 13.0, P = 0.96). When organized by academic rank, the difference between h-indices of those who completed fellowships was substantially greater at all ranks, with statistical significance at the associate professor rank (P = 0.003). Upon further examination by individual subspecialties, significant differences in relative research impact were noted (P < 0.0001). The stereotactic and functional fellowship was found to have the greatest mean h-index score, whereas the trauma/critical care fellowship had the lowest. CONCLUSION: No significant difference existed between the mean h-index scores of neurological surgeons who completed fellowships and those who did not. However, when stratified by academic rank, a trend was observed showing greater mean h-index scores for those who completed fellowships. This trend persists across nearly all subspecialties. Overall, being a senior faculty member corresponds with a greater h-index score, regardless of whether a fellowship was completed.

Is there an association between bruxism and reflux?

Yes, bruxism is associated with reflux. Sleep bruxism is prevalent in GERD patients.

Regurgitation of food by rumination has rarely been reported in latency-age children. A 7-year-old boy had symptoms of rumination, gagging, bruxism, and enuresis. During the oppositional stage of development many unresolved conflicts had developed between the patient and his parents. Short-term psychotherapy which focused on resolution of the power struggles produced rapid remission of the symptoms. A two-year follow-up showed no recurrence of difficulty. The purpose of this study was to examine the relationships among nocturnal jaw muscle activities, decreased esophageal pH, and sleep positions. Twelve adult volunteers, including 4 bruxism patients, participated in this study. Portable pH monitoring, electromyography of the temporal muscle, and audio-video recordings were conducted during the night in the subjects' homes. Rhythmic masticatory muscle activity (RMMA) episodes were observed most frequently, with single short-burst episodes the second most frequent. The frequencies of RMMA, single short-burst, and clenching episodes were significantly higher during decreased esophageal pH episodes than those during other times. Both the electromyography and the decreased esophageal pH episodes were most frequently observed in the supine position. These results suggest that most jaw muscle activities, ie, RMMA, single short-burst, and clenching episodes, occur in relation to gastroesophageal reflux mainly in the supine position. Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related structures, involving dental alterations (wear, fractures and cracks), periodontal signs (gingival recession and tooth mobility) and muscle-joint sensitivity, demanding a multidisciplinary treatment plan. This paper presents a case report in which bruxism associated with acid feeding, smoking habit and episodes of gastric reflow caused severe tooth wear and great muscular discomfort with daily headache episodes. From the diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow up with counseling on diet and smoking habits and management of the gastric disorders. This was followed by the installation of an interocclusal acrylic device in centric relation of occlusion (CRO) for reestablishment of the occlusal stability, vertical dimension of occlusion, anterior guides and return to normal muscle activity (90-day use approximately). After remission of initial symptoms, oral rehabilitation was implemented in CRO by means of full resin composite restorations and new interocclusal device for protection of restorations. Satisfactory esthetics, improved function and occlusal stability were obtained after oral rehabilitation. The patient has attended annual follow-ups for the past 2 years. The multidisciplinary treatment seems to be the key for a successful rehabilitation of severe cases of dental wear involving the association of different health disorders. INTRODUCTION: Chronic regurgitation of gastric acids in patients with gastroesophageal reflux disease may cause dental erosion, which can lead in combination with attrition or bruxism to extensive loss of coronal tooth tissue. CASE PRESENTATION: This clinical report describes treatment of severe tooth wear of a gastroesophageal reflux disease patient who is 54-year-old Turkish male patient. After his medical treatment, severe tooth wear, bruxism and decreased vertical dimensions were determined. The vertical dimension was re-established and maxillary and mandibular anterior and posterior teeth were prepared for metal-ceramic restorations. Metal-ceramic fixed partial dentures were fabricated as full mouth restorations for both maxillary and mandibular arches because of splinting all teeth. And then maxillary stabilization splint was fabricated for his bruxism history. CONCLUSION: Significant loss of coronal tooth structure must taken into consideration. Gastroesophageal reflux disease by itself or in combination with attrition, abrasion or bruxism may be responsible for the loss. An extensive diagnostic evaluation is essential for the medical and dental effects of the problem. The aim of this cross-over, randomized, single-blinded trial was to examine whether intra-esophageal acidification induces sleep bruxism (SB). Polysomnography with electromyogram (EMG) of masseter muscle, audio-video recording, and esophageal pH monitoring were performed in a sleep laboratory. Twelve healthy adult males without SB participated. Intra-esophageal infusions of 5-mL acidic solution (0.1 N HCl) or saline were administered. The frequencies of EMG bursts, rhythmic masticatory muscle activity (RMMA) episodes, grinding noise, and the RMMA/microarousal ratio were significantly higher in the 20-minute period after acidic infusion than after saline infusion. RMMA episodes including SB were induced by esophageal acidification. This trial is registered with the UMIN Clinical Trials Registry, UMIN000002923. ABBREVIATIONS: ASDA, American Sleep Disorders Association; EMG, electromyogram; GER, gastroesophageal reflux; LES, lower esophageal sphincter; NREM, non-rapid eye movement; REM, rapid eye movement; RMMA, rhythmic masticatory muscle activity; SB, sleep bruxism; SD, standard deviation; UES, upper esophageal sphincter. The aim of this study was to measure the progression of tooth wear in a cohort of 63 patients, 43 males and 20 females with a mean age of 39.1 years. Recruitment followed referral from general practice to Guy's Hospital for advice/management of tooth wear. Addition silicone impressions were taken at 6-month intervals for a total of 12 months; impressions were subsequently poured in type IV gypsum. Casts were scanned using a non-contacting laser profilometer and then superimposed using Geomagic® Qualify 11. Wear was measured in μm by tooth per time interval. A questionnaire highlighting dietary, parafunctional and gastric risk factors was obtained from each participant. Clustered multiple regression analysis was used to determine the relationship between tooth wear progression and risk factors. Maximum follow-up times were 6 months for 63 participants and 12 months for 30 participants. The measurement error was 15 μm. At the tooth level, 72.2% of 1,078 teeth wore <15 μm over a 6-month period. At the subject level, 77.7% of 63 participants showed median wear <15 μm over a 6-month period. There was a statistical trend towards tooth wear progression being associated with gastric risk factors (p < 0.05). The lower molars and the upper anterior teeth were the most commonly affected teeth; the lower molars and the upper central incisors were the most severely affected teeth. Tooth wear progression was slow in this cohort, suggesting that tooth wear may be cyclical and inactive in the majority of participants. Gastroesophageal reflux disease (GERD) is a gastrointestinal disorder in which stomach acids are chronically regurgitated into the esophagus and oral cavity. Continual exposure of the teeth to these acids can cause severe tooth wear. Dentists are often the first healthcare professionals to diagnose dental erosion in patients with GERD. This article presents a case report of a 27-year-old male smoker with tooth wear and dentin sensitivity caused by GERD associated with bruxism. After diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow-up with counseling on dietary and smoking habits, as well as management of the gastric disorders with medication. GERD management and the dental treatment performed for the eroded dentition are described, including diagnosis, treatment planning, and restorative therapy. STATEMENT OF PROBLEM: Rhythmic masticatory muscle activity, including sleep bruxism (SB), can be induced in healthy individuals by experimental esophageal acidification, which plays an important role in the pathogenesis of gastroesophageal reflux disease (GERD). However, no robust evidence supports the association between SB and GERD. PURPOSE: The purpose of this study was to investigate the association between SB and GERD. MATERIAL AND METHODS: Forty-five individuals were eligible to participate in this observational transversal study at the Gastroenterology Service of the Clinical Hospital of Porto Alegre, Brazil. The participants were classified into 2 groups, those with and without GERD, according to the Montreal Criteria and pH-metry/endoscopy findings. The diagnosis of SB was not assessed in a sleep laboratory but was based on self-report plus clinical inspection, according to the minimal diagnostic criteria of the American Academy of Sleep Medicine. The Lipp Stress Symptom Inventory was used to evaluate self-perceived stress. Univariate and multiple logistic regression analyses were performed with SB as dependent variable and GERD, sex, age, body mass index, and stress as predictors (α=.05; 90% power). RESULTS: The study population included individuals with SB without GERD (13.3%) and individuals with SB with GERD (31.1%). In participants with GERD, the prevalence of SB was 73.7%. Only the variable GERD was significantly associated with SB (P=.017; odds ratio 6.58; 95% confidence interval 1.40-30.98), although adjusted for stress and age. CONCLUSIONS: Sleep bruxism is prevalent in GERD patients, and GERD is highly associated with SB.

What is known about the value of mindfulness interventions in prostate cancer patients?

In prostate cancer patients, mindfulness interventions were well accepted and were effective in reducing stress, anxiety, avoidance, fear of cancer recurrence, cortisol levels and blood pressure, and improving quality of life, sleep quality and immune system functioning. In addition, mindfulness interventions promoted initiation of healthy dietary changes and decreases the rate of PSA increase and may slow the rate of tumor progression in cases of biochemically recurrent prostate cancer.

The objective of this study was to test the hypothesis that the regular practice of mindfulness meditation is associated with increased physiological levels of melatonin. Melatonin may be related to a variety of biologic functions important in maintaining health and preventing disease, including breast and prostate cancer. Previous studies have shown melatonin production is photosensitive and we suggest here that it also may be psychosensitive. A cross-sectional study of 12-hour (20:00-08:00) urinary 6-sulphatoxymelatonin was conducted from which we analyzed data from 8 women who regularly meditate (RM) and 8 women who do not meditate (NM). All samples were collected in the homes of study participants. Volunteers were recruited to provide 12-hour overnight samples of urine. All subjects collected the samples on one night during the same 1-week period. There was no explicit intervention. However, all RM were either graduates of, or teachers in, the University of Massachusetts Stress Reduction and Relaxation Program. The main outcome measure was the total excretion of urinary 6-sulphatoxymelatonin. Multiple linear regression (Proc GLM in SAS) was performed to test the effect of meditation (RM vs NM) on 6-sulphatoxymelatonin. The results of the study were that after controlling for the non-significant effect of menstrual period interval, we found an effect of meditation group (RM vs NM: b = 1.983; F = 6.78; p = 0.02) and age (for each integer year: b = 0.169; F = 8.41; p = 0.01). The conclusion is that study results are consistent with our hypothesis and indicate that melatonin might be a useful parameter in testing similar psycho-social interventions.(ABSTRACT TRUNCATED AT 250 WORDS) PURPOSE: Epidemiological and laboratory evidence indicates that a Western diet is associated with an increased incidence of prostate cancer. Specific components of the diet, such as high saturated fat, low fiber and high meat content, may have greatest clinical significance in the later stages of tumor promotion and progression. However, departure from the conventional diet is difficult to initiate and maintain. Therefore, we combined the well-known Mindfulness-Based Stress Reduction (MBSR) program with a low saturated fat, high-fiber, plant-based diet to determine the effect on the rate of change in prostate specific antigen (PSA) in patients with biochemical recurrence after prostatectomy. MATERIALS AND METHODS: We enrolled 10 men and their partners in a 4-month group-based diet and MBSR intervention. A pre-study post-study design in which each subject served as his own control was used to compare the rate of increase in and doubling time of PSA before and after intervention. RESULTS: The rate of PSA increase decreased in 8 of 10 men, while 3 had a decrease in absolute PSA. Results of the signed rank test indicated a significant decrease in the rate of increase in the intervention period (p = 0.01). Estimated median doubling time increased from 6.5 months (95% confidence interval 3.7 to 10.1) before to 17.7 months (95% confidence interval 7.8 to infinity) after the intervention. CONCLUSIONS: Our small study provides evidence that a plant-based diet delivered in the context of MBSR decreases the rate of PSA increase and may slow the rate of tumor progression in cases of biochemically recurrent prostate cancer. Larger-scale randomized studies are warranted to explore further the preventive and therapeutic potential of diet and lifestyle modification in men with prostate cancer. OBJECTIVES: This study investigated the relationships between a mindfulness-based stress reduction meditation program for early stage breast and prostate cancer patients and quality of life, mood states, stress symptoms, lymphocyte counts, and cytokine production. METHODS: Forty-nine patients with breast cancer and 10 with prostate cancer participated in an 8-week MBSR program that incorporated relaxation, meditation, gentle yoga, and daily home practice. Demographic and health behavior variables, quality of life (EORTC QLQ C-30), mood (POMS), stress (SOSI), and counts of NK, NKT, B, T total, T helper, and T cytotoxic cells, as well as NK and T cell production of TNF, IFN-gamma, IL-4, and IL-10 were assessed pre- and postintervention. RESULTS: Fifty-nine and 42 patients were assessed pre- and postintervention, respectively. Significant improvements were seen in overall quality of life, symptoms of stress, and sleep quality. Although there were no significant changes in the overall number of lymphocytes or cell subsets, T cell production of IL-4 increased and IFN-gamma decreased, whereas NK cell production of IL-10 decreased. These results are consistent with a shift in immune profile from one associated with depressive symptoms to a more normal profile. CONCLUSIONS: MBSR participation was associated with enhanced quality of life and decreased stress symptoms in breast and prostate cancer patients. This study is also the first to show changes in cancer-related cytokine production associated with program participation. OBJECTIVES: This study investigated the relationships between a mindfulness-based stress reduction meditation program for early stage breast and prostate cancer patients and quality of life, mood states, stress symptoms, and levels of cortisol, dehydroepiandrosterone-sulfate (DHEAS) and melatonin. METHODS: Fifty-nine patients with breast cancer and 10 with prostate cancer enrolled in an eight-week Mindfulness-Based Stress Reduction (MBSR) program that incorporated relaxation, meditation, gentle yoga, and daily home practice. Demographic and health behavior variables, quality of life, mood, stress, and the hormone measures of salivary cortisol (assessed three times/day), plasma DHEAS, and salivary melatonin were assessed pre- and post-intervention. RESULTS: Fifty-eight and 42 patients were assessed pre- and post-intervention, respectively. Significant improvements were seen in overall quality of life, symptoms of stress, and sleep quality, but these improvements were not significantly correlated with the degree of program attendance or minutes of home practice. No significant improvements were seen in mood disturbance. Improvements in quality of life were associated with decreases in afternoon cortisol levels, but not with morning or evening levels. Changes in stress symptoms or mood were not related to changes in hormone levels. Approximately 40% of the sample demonstrated abnormal cortisol secretion patterns both pre- and post-intervention, but within that group patterns shifted from "inverted-V-shaped" patterns towards more "V-shaped" patterns of secretion. No overall changes in DHEAS or melatonin were found, but nonsignificant shifts in DHEAS patterns were consistent with healthier profiles for both men and women. CONCLUSIONS: MBSR program enrollment was associated with enhanced quality of life and decreased stress symptoms in breast and prostate cancer patients, and resulted in possibly beneficial changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. These pilot data represent a preliminary investigation of the relationships between MBSR program participation and hormone levels, highlighting the need for better-controlled studies in this area. The purpose of this article is to (1) provide a comprehensive over view and discussion of mindfulness meditation and its clinical applicability in oncology and (2) report and critically evaluate the existing and emerging research on mindfulness meditation as an intervention for cancer patients. Using relevant keywords, a comprehensive search of MEDLINE, PsycInfo, and Ovid was completed along with a review of published abstracts from the annual conferences sponsored by the Center for Mindfulness in Medicine, Health Care, and Society and the American Psychosocial Oncology Society. Each article and abstract was critiqued and systematically assessed for purpose statement or research questions, STUDY DESIGN: The search produced 9 research articles published in the past 5 years and 5 conference abstracts published in 2004. Most studies were conducted with breast and prostate cancer patients, and the mindfulness intervention was done in a clinic-based group setting. Consistent benefits--improved psychological functioning, reduction of stress symptoms, enhanced coping and well-being in cancer outpatients--were found. More research in this area is warranted: using randomized, controlled designs, rigorous methods, and different cancer diagnoses and treatment settings; expanding outcomes to include quality of life, physiological, health care use, and health-related outcomes; exploring mediating factors; and discerning dose effects and optimal frequency and length of home practice. Mindfulness meditation has clinically relevant implications to alleviate psychological and physical suffering of persons living with cancer. Use of this behavioral intervention for oncology patients is an area of burgeoning interest to clinicians and researchers. OBJECTIVES: This study investigated the ongoing effects of participation in a mindfulness-based stress reduction (MBSR) program on quality of life (QL), symptoms of stress, mood and endocrine, immune and autonomic parameters in early stage breast and prostate cancer patients. METHODS: Forty-nine patients with breast cancer and 10 with prostate cancer enrolled in an eight-week MBSR program that incorporated relaxation, meditation, gentle yoga and daily home practice. Demographic and health behaviors, QL, mood, stress symptoms, salivary cortisol levels, immune cell counts, intracellular cytokine production, blood pressure (BP) and heart rate (HR) were assessed pre- and post-intervention, and at 6- and 12-month follow-up. RESULTS: Fifty-nine, 51, 47 and 41 patients were assessed pre- and post-intervention and at 6- and 12-month follow-up, respectively, although not all participants provided data on all outcomes at each time point. Linear mixed modeling showed significant improvements in overall symptoms of stress which were maintained over the follow-up period. Cortisol levels decreased systematically over the course of the follow-up. Immune patterns over the year supported a continued reduction in Th1 (pro-inflammatory) cytokines. Systolic blood pressure (SBP) decreased from pre- to post-intervention and HR was positively associated with self-reported symptoms of stress. CONCLUSIONS: MBSR program participation was associated with enhanced quality of life and decreased stress symptoms, altered cortisol and immune patterns consistent with less stress and mood disturbance, and decreased blood pressure. These pilot data represent a preliminary investigation of the longer-term relationships between MBSR program participation and a range of potentially important biomarkers. OBJECTIVES: Considerable evidence has shown that diet can affect both the incidence and the progression of prostate cancer. The objective of this study was to determine whether men in this situation could make a change to a diet emphasizing plant-based foods and fish and to examine the effect on quality of life (QOL) and prostate-specific antigen (PSA) velocity. METHODS: A total of 36 men and their partners were randomly assigned to attend a series of 11 dietary and cooking classes that also integrated mindfulness practice as a support in making the change or a wait-list control group. Assessments were made of dietary intake, QOL, and PSA at baseline, after intervention (11 weeks), and 3 months after intervention. RESULTS: The intervention group showed significant reductions in the consumption of saturated fat and increased consumption of vegetable proteins with accompanying reductions in animal proteins, including dairy products. They also showed increased QOL. Although no significant change was found in the rate of PSA increase between the two groups, the mean PSA doubling time for the intervention group was substantially longer at the 3-month follow-up visit than that of the controls. CONCLUSIONS: Men with a increasing PSA level after primary treatment were able to make a change to a prostate-healthy diet, accompanied by increases in QOL. No significant difference was found in the log PSA slope between the two groups; however, the PSA doubling time increased substantially in the intervention group compared with that in the controls. Future trials should examine the effect of the prostate-healthy diet with a larger sample of men for a longer period. PURPOSE: To investigate whether a mindfulness-based stress reduction program for cancer (MBSR-C) improved psychological and physical symptoms, quality of life (QOL), and stress markers among advanced-stage cancer patients and caregivers. DESIGN: A pilot within-subject design was used. METHOD: Patients previously diagnosed with advanced-stage breast, colon, lung, or prostate cancer and on treatment were recruited from the Moffitt Cancer Center and Research Institute. Twenty-six patient-caregiver dyads completed a modified 6-week, self-study MBSR-C program based on the Kabat-Zinn model. Psychological and physical symptoms and QOL were compared pre- and post-MBSR-C sessions. Salivary cortisol and interleukin-6 were assessed pre- and post-MBSR-C session at 1, 3, and 6 weeks. FINDINGS: Following the 6-week MBSR program, patients showed improvements in stress and anxiety (p < .05); caregivers' psychological and QOL also improved but were not statistically significant. Both patients and caregivers had decreases in cortisol at Weeks 1 and 3 (p < .05) but not at Week 6. Similar to cortisol levels at Week 6, salivary interleukin-6 levels were lower overall (before/after an MBSR-C session), compared with Week 1 for patients and caregivers. CONCLUSIONS: MBSR-C may be a beneficial intervention for reducing stress, anxiety, cortisol levels, and symptoms in advanced-stage cancer patients and may also benefit caregivers. Diet may represent a modifiable prostate cancer risk factor, but a vegetable-based prostate-healthy diet is a major change for most men. We used a ratio of animal to vegetable proteins (A:V) to evaluate whether a comprehensive dietary change was self-sustaining following completion of 11 weekly dietary and cooking classes that integrated mindfulness training. Thirty-six men with recurring prostate cancer were randomized to the intervention or wait-list control. Assessments were at baseline, 3 months, and 6 months. Of 17 men randomized to the intervention, 14 completed the requirements. Nineteen were randomized to control and 17 completed requirements. Compared with controls, a significant postintervention (3 months) decrease in A:V in the intervention group (P=0.01) was self-maintained 3 months postintervention (P=0.049). At each assessment, A:V was correlated with lycopene, fiber, saturated fat, and dietary cholesterol, four dietary components linked to clinically relevant outcomes in prostate cancer. Change in A:V was also significantly correlated with changes in fiber, saturated fat, and dietary cholesterol intake. Participants reported regular mindfulness training practice, and there was a significant correlation between mindfulness training practice and changes in both initiation and maintece of the change in A:V. These pilot results provide encouraging evidence for the feasibility of a dietary program that includes mindfulness training in supporting dietary change for men with recurrent prostate cancer and invite further study to explore the possible role of mindfulness training as a means of supporting both initiation of dietary changes and maintece of those changes over time.

What is known about prostate cancer screening in the UK ?

There is still no national screening programme established in the UK. Prostate cancer screening of asymptomatic men is not recommended by the National Screening Council at present and is not encouraged in the NHS. However, PSA tests are being performed for prostate cancer screening. The CAP and ProtecT trials are aimed to evaluate prostate cancer screening in the UK.

We used a nested case-control design on data from men in four prospective studies (from the UK, Maryland in the USA, and two from Finland) with available stored serum samples to determine whether there was an advantage in measuring both free prostate-specific antigen (PSA) and total PSA as a potential screening test for prostate cancer. Of these men, 247 were verified through national vital statistics offices as having died of prostate cancer, or having developed the disease, and 953 men who did not develop prostate cancer (controls) were selected, matched to cases for age, study centre and sample storage duration. Fixing the false-positive rate at 1%, the prostate cancer detection rate (sensitivity) over the 3 years following serum collection (based on 14 cancers) increased from an estimated 95% using total PSA to 97% using free and bound PSA (that is, bound to alpha-antichymotrypsin which together with the free form is total PSA). Over a 6-year period (based on 41 cancers) a similar difference occurred (52% and 56% detection rates respectively). We conclude that there is no material advantage in adding free to total PSA in prostate cancer screening trials. Prostate cancer screening of asymptomatic men is not recommended by the National Screening Council at present and is not encouraged in the NHS. A number of randomised controlled trials are under way to establish the place of routine screening of asymptomatic men. We report the possible practice of prostate cancer screening with reference to the appropriate age range for screening, how to screen for prostate cancer and how often, and what constitutes an abnormal result that would merit referral to a urologist for a prostate biopsy. OBJECTIVE: To explore the concerns and worries in men with uncomplicated lower urinary tract symptoms (LUTS, but no evidence of prostate cancer) relating to their symptoms. PATIENTS AND METHODS: There is no current prostate cancer screening programme in the UK. Evidence suggests that men with LUTS have the same risk of prostate cancer as aged-matched asymptomatic men. However, most men with LUTS are 'screened' with a digital rectal examination (DRE) and prostate specific antigen (PSA) testing as part of routine assessment. Whether this screening offers any benefit to patients and whether national screening for prostate cancer and subsequent early treatment offer any long-term survival or quality of life benefit is uncertain. Thus 30 men with uncomplicated LUTS were qualitatively interviewed to explore their concerns and worries about their symptoms. Interviews were transcribed verbatim and subjected to content analysis using validated techniques. RESULTS: Of the 30 men, 22 (73%) expressed a fear of prostate cancer at the time of their initial presentation. This fear was independent of race, social class and symptom severity; older men were less worried. Of the 22, 15 (68%) stated that after reassurance their symptoms were less bothersome and easier to cope with. CONCLUSIONS: These findings suggest there is a considerable gain in health by explicitly addressing the concerns of prostate cancer in men with uncomplicated LUTS. Informing these men of their true risk of prostate cancer (before or after a DRE and PSA estimate) may alleviate much of the bother associated with their symptoms. Despite no evidence of any greater risk of prostate cancer than in asymptomatic men, symptomatic men should continue to be screened after appropriate counselling. BACKGROUND: The role of Prostate Specific Antigen (PSA) testing in the early detection of prostate cancer is controversial. Current UK policy stipulates that any man who wishes to have a PSA test should have access to the test, provided he has been given full information about the benefits and limitations of testing. This study aimed to determine UK GPs' current reported practice regarding PSA testing, and their views towards informed decision-making and PSA testing. METHOD: Online questionnaire survey, with a sample of 421 GPs randomly selected from a database of GPs across the UK. RESULTS: 95% (400/421) of GPs responded. 76% of GPs reported having performed a PSA test for an asymptomatic man at least once in the previous three months, with 13% reported having tested more than five men in this period. A majority of GPs reported they would do a PSA test for men presenting with a family history and requesting a test, for asymptomatic men requesting a test and also for men presenting with lower urinary tract symptoms. Reported testing rates were highest for men with a family history. Amongst men with lower urinary tract symptoms and men with no symptoms, reported testing rates were significantly higher for older than younger men. The majority of GPs expressed support for the current policy (67%), and favoured both the general practitioner and the man being involved in the decision making process (83%). 90% of GPs indicated that they would discuss the benefits and limitation of testing with the man, with most (61%) preferring to ask the man to make a further appointment if he decides to be tested. CONCLUSION: This study indicates that PSA testing in asymptomatic men is a regular occurrence in the UK, and that there is general support from GPs for the current policy of making PSA tests available to 'informed' men who are concerned about prostate cancer. While most GPs indicated they would discuss the benefits and limitations prior to PSA testing, and most GPs favoured a shared approach to decision making, it is not known to what extent men are actually being informed. Research is needed to evaluate the most effective approach to assisting men in making an informed decision about whether or not to have a PSA test. INTRODUCTION: Screening for prostate cancer with serum prostate specific antigen (PSA) remains a controversial topic. The UK NHS Executive has issued extensive guidance stressing the importance of adequate counselling prior to performing this test. This study aims to assess men's knowledge of the PSA test at the time of their referral and their attitude towards screening. PATIENTS AND METHODS: A total of 219 men referred to urology via the 'fast track' prostate cancer service were recruited into the study. Of these, 191 were referred from primary care and 28 from secondary care. All men completed a questionnaire regarding their knowledge and expectation of the test. RESULTS: The response rate for completed questionnaires was 100%. Overall, 91 (41.5%) men were aware that their PSA had been performed prior to referral and only 79 (36%) men understood why the test was being done. Patients referred from secondary care appeared to be better informed. Despite these figures, 175 (80%) men said they would recommend PSA testing to a friend or colleague, and 196 (89%) men said the test should be broadly publicised. CONCLUSIONS: Nearly two-thirds of the men referred to urology with an elevated PSA were unaware that they had even had their PSA done. Information about the limitations of PSA testing and the consequence of a positive test result had been deficient. Informed counselling for the PSA test should form part of the consultation of any physician intending to undertake this test whether for lower urinary tract symptoms or for prostate cancer screening. OBJECTIVE: To evaluate the psychosocial impact of participation in a population-based prostate-specific antigen (PSA) testing programme, akin to screening, and to explore the relationship between urinary symptoms reported before PSA testing and the response to the subsequent PSA result. PATIENTS AND METHODS: This prospective questionnaire study was nested within the case-finding component of the ProtecT (prostate testing for cancer and treatment) feasibility study (ISRCTN20141297). Men aged 50-69 years from 18 general practices in three cities in the UK completed the Hospital Anxiety and Depression Scale (HADS), the Short Form-12 (SF-12) Health Survey, and the International Continence Society 'male' (ICSmale) questionnaires before giving consent for a PSA test in a community clinic (baseline). Men with an 'abnormal' PSA result returned for further investigation (including biopsy) and repeated these questionnaires before biopsy. RESULTS: At baseline, study participants had similar levels of anxiety and depression to the general male population. There was no increase in the HADS scores, or reduction in the SF-12 mental health component summary score, on attendance at the biopsy clinic after receiving an 'abnormal' PSA result. Urinary symptoms were associated with levels of anxiety and depression before receiving a PSA result (baseline), but were not associated with anxiety and depression at biopsy independently of baseline scores. Therefore changes in anxiety or depression at biopsy did not appear to differ between those with and without urinary symptoms. CONCLUSIONS: This study confirms the findings of other studies that the deleterious effects of receiving an abnormal PSA result during population screening are not identified by generic health-status questionnaires. Comparisons with outcomes of studies measuring cancer-specific distress and using qualitative research methods raise the question of whether a prostate cancer screening-specific instrument is required. However, a standardized measure of anxiety identified differences at baseline between those who did and did not report urinary symptoms. These findings suggest that it might be advisable to better inform men undergoing PSA testing about the uncertain relationship between urinary symptoms and prostate cancer, to minimize baseline levels of psychological distress. AIDIT (Advancing International Co-operation and Developing Infrastructure for Targeted Screening of Prostate Cancer in Men with Genetic Predisposition) is a project funded by the Sixth Framework Programme of the European Community which is endeavouring to facilitate co-operation between European countries in the field of cancer research. The project also aims to raise awareness of familial prostate cancer among health professionals and the public within the associated candidate countries (ACCs) and new member states of the European Union (EU). AIDIT will focus on linking clinical and research teams in the ACCs and new member states with the IMPACT Consortium (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls), an international team investigating screening and diagnosis for men with a genetic risk of prostate cancer predisposition genes BRCA1 or BRCA2). Cancer research has been targeted as a high priority for the European Community; however, research is most successful when centralised and well coordinated, avoiding the duplication and fragmentation associated with smaller, isolated studies. AIDIT will consolidate the current IMPACT consortium and allow research partners from across the world to benefit from shared knowledge and experience. To date, the AIDIT team has established a website to facilitate communication between project collaborators (www.impact-study.co.uk), has been represented at several international meetings and has facilitated a conference for the IMPACT study to bring together international research teams, clinicians and policy makers. BACKGROUND: Worldwide, the use of prostate specific antigen (PSA) testing as a screen for prostate cancer is contentious. Whilst there is no National UK Screening programme, many men undergo opportunistic screening. This study investigates UK urologist's usage of PSA and the awareness surrounding the Department of Health (DoH) PSA guidelines. METHODS: Urologists were sent a questionnaire regarding PSA cut-off values. RESULTS: Of the 733 urologists eligible to participate in this study 346 returned completed questionnaires giving a response rate of 47%. The most commonly generally used age-related PSA cut-off values (36% of respondents) are--3.5 ng/ml for 50 - 59 year olds, 4.5 ng/ml for 60 - 69 year olds and 6.5 ng/ml for over 70 year olds. Two-thirds (58%, 200/346) of respondents were aware of the DoH PSA guidelines but only 20% (n = 69/346) follow these guidelines. The majority of respondents (68%, n = 234/346) used higher PSA cut-offs than recommended by the DoH. The level of compliance showed marked regional variation with a range from 7% to 44% (median 19%). In addition, it was apparent that lower PSA cut-off values were used in private practice as opposed to the National Health Service. CONCLUSION: A nationwide lack of agreement on PSA cut-off values may generate a variable standard of care both regionally and in NHS versus private practice. Generally, higher PSA cut-off values are being used than recommended by the DoH guidance. BACKGROUND: Increased use of prostate specific antigen (PSA) has been associated with increased prostate cancer incidence. Ireland is estimated to have one of the highest prostate cancer incidences in Europe and has no national guidelines for prostate cancer screening. GPs have a pivotal role in influencing PSA testing, therefore, our aim was to describe GP testing practices and to identify factors influencing these. METHODS: A postal survey, including questions on clinical practice and experience, knowledge and demographics was distributed to all GPs (n = 3,683). The main outcomes were (i) PSA testing asymptomatic men and (ii) "inappropriate" PSA testing, defined as testing asymptomatic men aged < 50 or > 75 years. Factors associated with these outcomes were identified using logistic regression. RESULTS: 1,625 GPs responded (response rate corrected for eligibility = 53%). Most respondents (79%) would PSA test asymptomatic men. Of these, 34% and 51% would test asymptomatic men < 50 and > 75 years, respectively. In multivariate analyses, GPs were more likely to test asymptomatic men if they were >or= 50 years, in practice >or= 10 years, female or less knowledgeable about PSA efficacy. Male GPs who would have a PSA test themselves were > 8-times more likely to PSA test asymptomatic men than GPs who would not have a test. GPs who had an asymptomatic patient diagnosed with prostate cancer following PSA testing, were > 3-times more likely to test asymptomatic men. Practice-related factors positively associated with testing included: running 'well man' clinics, performing occupational health checks and performing other tests routinely with PSA. Factors positively associated with 'inappropriate' testing included; being male and willing to have a PSA test, having worked/trained in the UK and supporting annual PSA testing. 91% of respondents supported the development of national PSA testing guidelines. CONCLUSION: Our findings suggest that widespread PSA testing of asymptomatic men in primary care is primarily due to a combination of clinical experience, poor knowledge and the support of doctors for PSA testing, as evidenced by the willingness of male doctors to have a PSA test. There is an urgent need for education and support for GPs concerning prostate cancer screening, starting with the implementation of national guidelines. BACKGROUND: Web-based decision aids are known to have an effect on knowledge, attitude, and behavior; important components of informed decision making. We know what decision aids achieve in randomized controlled trials (RCTs), but we still know very little about how they are used and how this relates to the informed decision making outcome measures. OBJECTIVE: To examine men's use of an online decision aid for prostate cancer screening using website transaction log files (web-logs), and to examine associations between usage and components of informed decision making. METHODS: We conducted an observational web-log analysis of users of an online decision aid, Prosdex. Men between 50 and 75 years of age were recruited for an associated RCT from 26 general practices across South Wales, United Kingdom. Men allocated to one arm of the RCT were included in the current study. Time and usage data were derived from website log files. Components of informed decision making were measured by an online questionnaire. RESULTS: Available for analysis were 82 web-logs. Overall, there was large variation in the use of Prosdex. The mean total time spent on the site was 20 minutes. The mean number of pages accessed was 32 (SD 21) out of a possible 60 pages. Significant associations were found between increased usage and increased knowledge (Spearman rank correlation [rho] = 0.69, P < .01), between increased usage and less favorable attitude towards PSA testing (rho = -0.52, P < .01), and between increased usage and reduced intention to undergo PSA testing (rho = -0.44, P < .01). A bimodal distribution identified two types of user: low access and high access users. CONCLUSIONS: Increased usage of Prosdex leads to more informed decision making, the key aim of the UK Prostate Cancer Risk Management Programme. However, developers realistically have roughly 20 minutes to provide useful information that will support informed decision making when the patient uses a web-based interface. Future decision aids need to be developed with this limitation in mind. We recommend that web-log analysis should be an integral part of online decision aid development and analysis. TRIAL REGISTRATION: ISRCTN48473735; http://www.controlled-trials.com/ISRCTN48473735 (Archived by WebCite at http://www.webcitation.org/5pqeF89tS). The European Randomised Study of Screening for Prostate Cancer (ERSPC) demonstrated a significant reduction in prostate cancer-specific mortality. The ongoing Comparison Arm for ProtecT (CAP) cluster randomised controlled trial (RCT) evaluates prostate cancer screening effectiveness by comparing primary care centres allocated to a round of prostate specific antigen (PSA) testing (intervention) or standard clinical care. Over 550 centres (around 450,000 men) were randomised in eight United Kingdom areas (2002-2008). Intervention group participants were also eligible for the ProtecT (Prostate testing for cancer and Treatment) RCT evaluating active monitoring, radiotherapy and radical prostatectomy treatments for localised prostate cancer. In ProtecT, over 1500 of around 3000 men with prostate cancer were randomised from over 10,000 with an elevated PSA in around 111,000 attendees at clinics. Investigation of the psychological impact of screening in a sub-sample showed that 10% of men still experienced high distress up to 3 months following prostate biopsies (22/227), although most were relatively unaffected. The risk of prostate cancer with a raised PSA was lower if urinary symptoms were present (frequent nocturia odds ratio (OR) 0.44, 95% confidence interval (CI) 0.22-0.83) or if a repeat PSA decreased by > or = 20% prior to biopsy (OR 0.43, 95% CI 0.35-0.52). Men aged 45-49 years attended PSA clinics less frequently (442/1299, 34%) in a nested cohort with a cancer detection rate of 2.3% (10/442). The CAP and ProtecT trials (ISRCTN92187251 and ISRCTN20141217) will help resolve the prostate cancer screening debate, define the optimum treatment for localised disease and generate evidence to improve men's health. OBJECTIVES: To assess whether people with learning disability in the UK have poorer access to cancer screening. DESIGN: Four cohort studies comparing people with and without learning disability, within the recommended age ranges for cancer screening in the UK. We used Poisson regression to determine relative incidence rates of cancer screening. SETTING: The Health Improvement Network, a UK primary care database with over 450 General practices. PARTICIPANTS: Individuals with a recorded diagnosis of learning disability including general diagnostic terms, specific syndromes, chromosomal abnormalities and autism in their General Practitioner computerised notes. For each type of cancer screening, a comparison cohort of up to six people without learning disability was selected for each person with a learning disability, using stratified sampling on age within GP practice. MAIN OUTCOME MEASURES: Incidence rate ratios for receiving 1) a cervical smear test, 2) a mammogram, 3) a faecal occult blood test and 4) a prostate specific antigen test. RESULTS: Relative rates of screening for all four cancers were significantly lower for people with learning disability. The adjusted incidence rate ratios (95% confidence intervals) were Cervical smears: Number eligible with learning disability = 6,254; IRR = 0.54 (0.52-0.56). Mammograms: Number eligible with learning disability = 2,956; IRR = 0.76 (0.72-0.81); Prostate Specific Antigen: Number eligible = 3,520; IRR = 0.87 (0.80-0.96) and Faecal Occult Blood Number eligible = 6,566; 0.86 (0.78-0.94). Differences in screening rates were less pronounced in more socially deprived areas. Disparities in cervical screening rates narrowed over time, but were 45% lower in 2008/9, those for breast cancer screening appeared to widen and were 35% lower in 2009. CONCLUSION: Despite recent incentives, people with learning disability in the UK are significantly less likely to receive screening tests for cancer that those without learning disability. Other methods for reducing inequalities in access to cancer screening should be considered. INTRODUCTION: Prostate cancer is the commonest cancer in men and a major health issue worldwide. Screening for early disease has been available for many years, but there is still no national screening programme established in the United Kingdom. OBJECTIVE: To assess the latest evidence regarding prostate cancer screening and whether it meets the necessary requirements to be established as a national programme for all men. METHODS: Electronic databases and library catalogues were searched electronically and manual retrieval was performed. Only primary research results were used for the analysis. RESULTS: In recent years, several important randomised controlled trials have produced varied outcomes. In Europe the largest study thus far concluded that screening reduced prostate cancer mortality by 20%. On the contrary, a large American trial found no reduction in mortality after 7-10 years follow-up. Most studies comment on the adverse effects of screening - principally those of overdiagnosis and subsequent overtreatment. DISCUSSION: Further information about the natural history of prostate cancer and accuracy of screening is needed before a screening programme can be truly justified. In the interim, doctors and patients should discuss the risks, benefits and sequelae of taking part in voluntary screening for prostate cancer.

Which hormone abnormalities are common in Williams syndrome ?

Thyroid hormone abnormalities are common in Williams syndrome. Oxytocin and vasopressin, cortisol, growth hormone and calcitonin were also implicated in the Williams syndrome.

We have investigated the possibility of mutations in the calcitonin/calcitonin gene related peptide (CGRP) gene in children with Williams syndrome. Involvement of the calcitonin/CGRP gene in Williams syndrome is postulated on the basis that Williams syndrome children often have infantile hypercalcemia and deficient expression of calcitonin, a hormone that lowers serum calcium levels. To test the hypothesis that mutations in the calcitonin/CGRP gene might be responsible for the reduced calcitonin levels, we examined the calcitonin/CGRP gene structure in Williams syndrome children. Analysis of white blood cell DNA by Southern blot hybridizations in 5 individuals did not show any detectable large deletions or rearrangements in the calcitonin/CGRP gene locus. The possibility of small deletions or point mutations within the exon encoding the mature calcitonin hormone is unlikely based on ribonuclease protection assays with patient DNA amplified by the polymerase chain reaction (PCR) technique. These findings suggest that the calcitonin deficiency might be due either to mutations elsewhere in the gene or to defects in the cellular machinery needed for calcitonin synthesis and/or secretion. Supravalvular aortic stenosis (SVAS) may occur as an isolated autosomal domit trait or as a feature of Williams syndrome. It has been suggested that a defect in calcitonin function may play a role in Williams syndrome. We have excluded calcitonin as a candidate gene for SVAS using a gene specific probe. The human calcitonin receptor (CTR) is a transmembrane peptide with dual action as a receptor for the hormone calcitonin and as an extracellular calcium sensor. Therefore, CTR dysfunction could lead to disorders of calcium metabolism associated with hypercalcemia, such as the Williams syndrome (WS). WS is a developmental disorder caused by a deletion at chromosome 7q11.23 that includes the elastin locus (ELN). We have mapped the CTR gene (CALCR) to chromosome band 7q21.3 by polymerase chain reaction and single-strand conformation analysis of somatic cell hybrids as well as fluorescence in situ hybridization (FISH) to metaphase chromosome spreads. Two-color FISH cohybridizing CTR and ELN probes confirmed that CALCR maps telomeric to ELN. Subsequent analysis of chromosome spreads from four WS patients revealed deletion of the ELN locus in all of them and normal hybridization of CTR probes to both chromosome 7 homologues, indicating that CALCR lies outside the deleted region. A 31-year-old man who had been under regular hemodialysis for 6 months was diagnosed as Williams syndrome (WS) by fluorescence in situ hybridization (FISH) chromosomal analysis. The association of WS and chronic renal failure (CRF) is only rarely encountered. Endocrinological examinations revealed hypergonadotropic hypogonadism. Prolonged and exaggerated responses of adrenocorticotropin (ACTH) to insulin-induced hypoglycemia and corticotropin releasing hormone (CRH) were also noted. While most of the endocrinological abnormalities observed in this patient could be attributed to altered endocrine circumstances in CRF, some findings stand in contrast. Furthermore, the testicular biopsy specimen showed severe hypospermatogenesis. Endocrine disorders observed in this patient may be at least in part, responsible for various clinical features underlying WS. Growth retardation is a consistent finding in Williams-Beuren syndrome. The cause of short stature in this syndrome is unknown. Endocrine studies have failed to reveal abnormalities in the growth hormone-insulin-like growth factor I axis. We report a boy with confirmed Williams-Beuren syndrome, who was found to have classical growth hormone deficiency and responded well to growth hormone therapy. CONCLUSION: Although growth hormone deficiency is not likely to be a common cause of short stature in Williams-Beuren syndrome, we nevertheless recommend evaluation of the growth hormone-insulin-like growth factor I axis in all cases. A girl with Williams syndrome (WS) presented with elevated thyrotropin (TSH) levels (7.0 microU/ml), normal free thyroid hormone concentrations, and absent antithyroid autoantibodies. Thyroid ultrasonography and scintigraphy showed hemiagenesis of the left lobe and no evidence of ectopic tissue. TSH response to thyrotropin-releasing hormone (TRH) injection (200 microg/mq, i.v.) was exaggerated and prolonged, suggesting subclinical hypothyroidism. The biological activity of circulating TSH was slightly below the normal range [TSH bioactivity (B) to immunoreactivity (I) ratio (TSH B/I) = 0.4, normal: 0.6-2.2]. These abnormalities are similar to those seen in patients with hypothalamic hypothyroidism. Thyroid function is not a recognized manifestation of WS and is not routinely investigated. However, abnormalities of the hypothalamic-pituitary-thyroid (HPT) axis and thyroid dysgenesis have been found in other WS cases. Genes mapping at 7q11.23, contiguous to the chromosomal region deleted in most WS patients, may be involved in the development of the thyroid gland, contributing to the complex phenotype of WS. The authors report a female presenting with congenital heart defects, liver hemangiomas, and facial dysmorphisms admitted to hospital at 3 months of age because of feeding difficulties and poor growth. She had hypotonia and large tongue, "coarse" face, and umbilical hernia in presence of complex congenital cardiovascular malformations. In spite of normal neonatal screening we performed serum levels of thyroid hormones. Thyrotropin level was very high (>50 microU/ml; normal value 0.2-4 microU/ml), while serum free T(3) (FT3) and free T(4) (FT4) levels were normal (FT3 3.6 pg/ml, normal value 2.8-5.6 pg/ml; FT4 11.6 pg/ml, normal value 6.6-14 pg/ml); antithyroid autoantibodies were absent. Thyroid scintigraphy with sodium 99m Tc pertechnetate showed a small ectopic thyroid located in sublingual position, so treatment with L-thyroxine 37.5 microg/24 hr was started with rapid improvement of the clinical picture. At 17 months of age the patient developed the complete characteristic phenotype of Williams syndrome (WS); the clinical diagnosis was proven by fluorescent in situ hybridization (FISH) analysis which showed hemizygous deletion of the elastin gene on chromosome 7. Recently a case of thyroid hemiagenesis in a child with WS has been reported; our patient underscores the association of hypothyroidism and WS. Moreover, our case shows that clinical manifestations of hypothyroidism may be present and the treatment may be necessary as it is in isolated congenital hypothyroidism. Pre- and postnatal growth retardation of unknown pathogenesis is a common clinical feature in patients with Williams-Beuren syndrome (WBS). However, growth hormone deficiency (GHD) has not been considered a major cause of growth retardation. There is only one patient in the literature with confirmed GHD who responded well to human growth hormone (hGH) therapy. We report a female infant with confirmed WBS who, through provocative testing, was found to have GHD and who responded satisfactorily to hGH therapy. Height SDS was -4.2 at the age of 12 months when hGH was initiated and increased to -0.8 at the age of 4.25 years. The pathogenesis of GHD in our patient is unclear. Nevertheless, the elevated levels of prolactin and the response of hGH to growth hormone releasing hormone (GHRH) administration are indicative of a hypothalamic rather than pituitary defect. In conclusion, GH deficiency might contribute to the growth failure in a number of patients with WBS and in such cases hGH therapy will most likely improve final height. OBJECTIVE: To evaluate the prevalence of abnormalities of thyroid function and morphology in a cohort of patients with Williams syndrome (WS). METHODS: Serum concentrations of free-T3, free-T4, TSH, thyroperoxidase antibodies (TPOA) and thyroglobulin antibodies (TgA), as well as ultrasonographic data, of 20 patients with WS (12 females and eight males), aged 1.7-34.9 years, were evaluated. RESULTS: Three cases (15%) of subclinical hypothyroidism were identified. Overt hypothyroidism was diagnosed in two cases (10%). Thyroid antibodies were negative in all patients. Fourteen patients (70%) showed thyroid hypoplasia involving the entire gland. In these patients, the left thyroid lobe appeared usually, but not significantly, reduced compared with the right thyroid lobe. One patient (5%) showed thyroid hemiagenesis. Only five patients (25%) showed a thyroid with normal volume, and of these five, one patient showed marked thyroid hypoplasia of the left lobe. In all WS patients with diagnosis of subclinical or overt hypothyroidism, thyroid hypoplasia was detected. No cases of subclinical or overt hypothyroidism were found in WS with normal thyroid volume. CONCLUSIONS: This study confirms the presence of alterations of thyroid function in WS and also suggests the frequent occurrence of abnormalities of thyroid morphology in these patients. Patients with WS should be monitored for thyroid function and a thyroid ultrasound screening should be considered, especially in those patients with changes in thyroid function. Williams syndrome (WS) is a well-known microdeletion syndrome characterized by specific facial features, retardation in growth and development, typical personality and cardiac defects. Poor growth potential is further affected by central precocious puberty (CPP) which is frequent in these patients. A WS patient with CPP is presented, whose pubertal development and bone age progression were arrested by administration of GnRH analogues. The case is reported to discuss the role of GnRH analogues for management of CPP in patients with WS. Thyroid involvement in Williams syndrome (WS) was recently reported in two small groups of patients, both showing an increased prevalence of elevation of TSH serum concentration; in one of the two reports, 70% of the patients demonstrated a hypoplasia of thyroid gland as well. In our institution, we currently follow a large population of WS patients who periodically undergo a multispecialist clinical evaluation that includes ultrasound evaluation of the thyroid gland, and levels of FT3, FT4, TSH, and anti-thyroid antibodies. Here, we report on the prevalence of thyroid structural and functional anomalies, in a population of 95 WS patients, half of them followed for more than 5 years. Our study confirms the increased incidence of both elevated TSH serum values (37.9% in our sample) and thyroid gland hypoplasia (74.7%). Moreover, we demonstrated that TSH elevation declines with age. For this reason, we suggest that a complete thyroid evaluation be performed in every patient with WS, and that this medical complication should be periodically searched for in follow-up visits. OBJECTIVE: To verify the prevalence of morpho-volumetric and functional thyroid abnormalities in young patients with Williams syndrome (WS). STUDY DESIGN: Ninety-two patients with WS (49 boys and 43 girls, 0.2-17.2 years of age) underwent evaluation of thyroid function by means of thyroid-stimulating hormone (TSH), fT3, and fT4 measurement. Thyroid ultrasonography was performed in 37 patients. Thyroid antibodies (thyroid peroxidase and thyroglobulin) were measured in all patients with abnormal thyroid function tests. RESULTS: None of our patients had overt hypothyroidism; 29 patients (31.5%) had subclinical hypothyroidism. Thyroid antibodies were absent in all patients. The prevalence of patients with subclinical hypothyroidism was significantly higher in the younger patients. Ultrasonography revealed morphological or volumetric abnormalities of the thyroid gland in 67.5% of patients; these abnormalities were more frequently observed in the older children. CONCLUSIONS: Subclinical hypothyroidism is a frequent but stable finding in young children with WS. The great majority of patients with WS >10 years, either with normal or hypoplastic thyroid, have normal thyroid function. Therefore, we suggest yearly monitoring of thyroid function and sonographic studies at least once in patients with WS. Treatment should be reserved for the patients with overt hypothyroidism or for those whose thyroid function shows signs of progressive deterioration. In the Williams-Beuren syndrome (WBS), disorders of the thyroid function and morphology have been reported and programs of thyroid screening and surveillance are recommended. However, the frequency of biochemical thyroid assessment, particularly in the first year of life, is being debated. In this report we describe an infant with WBS and congenital hypothyroidism, due to an important thyroid hypoplasia. The patient, a 1-month-old female, negative at primary neonatal thyroid screening, was referred to our hospital for dyspnea. Thyroid function tests showed a raised TSH (42 mIU/l; normal range 0.5-4 mIU/l) with a low FT(4) concentration (10.21 pmol/l; normal range: 10.29-24.45 pmol/l). Ultrasound examination of the neck showed a significant thyroid hypoplasia, whereas (99m)Tc-pertechnetate thyroid scintigraphy evidenced a thyroid gland in normal position, with reduced shape and overall weak fixation. Therefore, treatment with L-thyroxinewas started. Thyroid hypoplasia is a frequent characteristic of WBS and abnormalities of thyroid function are common in patients with this feature. Therefore, the possibility of congenital hypothyroidism should always be taken into consideration too and, even if congenital hypothyroidism neonatal screening is negative, thyroid (morphology and function) evaluation should be regularly assessed when the diagnosis is made and, thereafter, every year in the first years of life. The molecular and neural mechanisms regulating human social-emotional behaviors are fundamentally important but largely unknown; unraveling these requires a genetic systems neuroscience analysis of human models. Williams Syndrome (WS), a condition caused by deletion of ~28 genes, is associated with a gregarious personality, strong drive to approach strangers, difficult peer interactions, and attraction to music. WS provides a unique opportunity to identify endogenous human gene-behavior mechanisms. Social neuropeptides including oxytocin (OT) and arginine vasopressin (AVP) regulate reproductive and social behaviors in mammals, and we reasoned that these might mediate the features of WS. Here we established blood levels of OT and AVP in WS and controls at baseline, and at multiple timepoints following a positive emotional intervention (music), and a negative physical stressor (cold). We also related these levels to standardized indices of social behavior. Results revealed significantly higher median levels of OT in WS versus controls at baseline, with a less marked increase in AVP. Further, in WS, OT and AVP increased in response to music and to cold, with greater variability and an amplified peak release compared to controls. In WS, baseline OT but not AVP, was correlated positively with approach, but negatively with adaptive social behaviors. These results indicate that WS deleted genes perturb hypothalamic-pituitary release not only of OT but also of AVP, implicating more complex neuropeptide circuitry for WS features and providing evidence for their roles in endogenous regulation of human social behavior. The data suggest a possible biological basis for amygdalar involvement, for increased anxiety, and for the paradox of increased approach but poor social relationships in WS. They also offer insight for translating genetic and neuroendocrine knowledge into treatments for disorders of social behavior. Williams syndrome (WS) is a neurodevelopmental genetic disorder associated with high rates of anxiety and social issues. We examined diurnal cortisol, a biomarker of the stress response, in adults with WS in novel and familiar settings, and compared these profiles to typically developing (TD) adults. WS and TD participants had similar profiles in a familiar setting, while participants with WS had elevated cortisol late in the day in the novel setting when social demands were higher. The cortisol awakening response in WS was associated with parent-reported levels of somatic complaints and social difficulties. Results suggest that adults with WS have a typical diurnal cortisol profile that may be sensitive to social and activity transitions throughout the day.

The secreted frizzled-related protein 3 (sFPR3) is altered in human cancers. Are its level found to increase or to decrease?

SFRPs are down-regulated in several cancers and this is often correlated with poor prognosis, as has been shown for breast, colorectal, and a number of other cancers. (PMID: 21494614) We performed tissue microarray and found that the level of sFRP3 protein was high in normal kidney, low in primary renal cancer tissues, and high in metastatic renal cancer tissues. (PMID: 20160027)

Wnt signaling pathway is important for development and carcinogenesis. Alterations of this pathway, such as mutations in adenomatous polyposis coli (APC) gene and activation mutations of beta-catenin, would result in stabilization of beta-catenin and subsequent translocation to nucleus where genes are transcribed. Recently, a receptor of Wnt, FzE3 was found to be up-regulated in esophageal carcinoma while a non-receptor antagonist of Wnt, secreted frizzled related protein (hsFRP) was found to be down-regulated in some cancer. These findings suggested that FzE3 is a potential oncogene while hsFRP is a potential tumor suppressor gene. We aimed to investigate whether FzE3 and hsFRP were altered in gastric cancer. Twelve cases of gastric cancer, including 7 cases of intestinal type, 4 cases of diffuse type and I case of mixed type, were studied. FzE3 and hsFRP mRNAs were expressed in most of the paired normal gastric tissues. FzE3 was over-expressed in 9 cases (75%) of gastric carcinoma tissues while hsFRP was down-regulated in 2 cases (16%). Beta-catenin nuclear staining was identified in 3 cases (27%) and cyclin D1 was expressed in 5 cases (41%) of cancer samples. All these cases were associated with either up-regulation of FzE3 or down-regulation of hsFRP. Our results suggested that alterations of FzE3 or hsFRP were frequent in gastric cancer. These provide alternative mechanisms leading to activation of Wnt signaling pathway in gastric carcinogenesis. The ability of Frzb/secreted Frizzled-related protein 3 (sFRP3) to inhibit Wnt signaling and the localization of Frzb/sFRP3 on chromosome 2q to a region frequently deleted in cancers have led some investigators to hypothesize that Frzb/sFRP3 is a tumor suppressor gene. Here, we examined the biological effects of Frzb/sFRP3 on an androgen-independent prostate cancer cell model. We showed that expression of Frzb/sFRP3 in PC-3 cells resulted in decreased colony formation in soft agar and a dramatic inhibition of tumor growth in a xenograft mouse model. When cellular morphology was examined, PC-3 cells expressing Frzb/sFRP3 exhibited an increase in cell-cell contact formation accompanied by a pronounced induction of epithelial markers E-cadherin and keratin-8 and down-regulation of mesenchymal markers N-cadherin, fibronectin, and vimentin. This phenomenon suggested a reversal of epithelial-to-mesenchymal transition and a less invasive phenotype. Indeed, further in vitro studies with a Matrigel assay showed that Frzb/sFRP3 decreased the invasive capacity of PC-3 cells. These changes in the biology of PC-3 cells are associated with a decrease in the expression and activities of both matrix metalloproteinase (MMP)-2 and MMP-9 as well as decreases in AKT activation, cytosolic beta-catenin levels, T-cell factor transcription activity, and expression of Slug and Twist. In addition, transfection of PC-3 with a domit-negative low-density lipoprotein receptor-related protein 5 (DN-LRP5) coreceptor showed similar biological effects as Frzb/sFRP3 transfection. Together, these data suggest that Frzb/sFRP3 and DN-LRP5 exhibit antitumor activity through the reversal of epithelial-to-mesenchymal transition and inhibition of MMP activities in a subset of prostate cancer. Deciphering the molecular basis of cancer is critical for developing novel diagnostic and therapeutic strategies. To better understand the early molecular events involving osteogenic sarcoma (OGS), we have initiated a program to identify potential tumor suppressor genes. Expression profiling of total RNA from ten normal bone cell lines and eleven OGS-derived cell lines by microarray showed 135-fold lower expression of FRZB/sFRP3 mRNA in OGS cells compared to bone cells; this down-regulation of Frzb/sFRP3 mRNA expression was found to be serum-independent. Subsequently, fourteen OGS biopsy specimens showed nine-fold down-regulation of Frzb/sFRP3 mRNA expression compared to expression in eight normal bone specimens as determined by microarray. FRZB /sFRP3 protein level was also found to be at a very low level in 4/4 OGS cell lines examined. Quantitation by RT-PCR indicated approximately 70% and approximately 90% loss of Frzb/sFRP3 mRNA expression in OGS biopsy specimens and OGS-derived cell lines respectively, compared to expression in bone (p<0.0001). Hybridization experiments of a cDNA microarray containing paired normal and tumor specimens from nineteen different organs did not show any significant difference in the level of Frzb/sFRP3 mRNA expression between the normal and the corresponding tumor tissues. Exogenous expression of FRZB/sFRP3 mRNA in two OGS-derived cell lines lacking endogenous expression of the mRNA produced abundant mRNA from the exogenous gene, eliminating degradation as a possibility for very low level of FRZB/sFRP3 mRNA in OGS specimens. Results from PCR-based experiments suggest that the FRZB/sFRP3 gene is not deleted in OGS cell lines, however, karyotyping shows gross abnormalities involving chromosome 2 (location of the FRZB gene) in five of twelve OGS-derived cell lines. Together, these data suggest a tumor-suppressive potential for FRZB/sFRP3 in OGS. Osteoblast impairment occurs within multiple myeloma cell infiltration into the bone marrow. Canonical Wnt signaling activation in osteoprogenitor cells is involved in osteoblast formation through the stabilization of dephosphorylated beta-catenin and its nuclear translocation. The effects of multiple myeloma cells on Wnt signaling in human mesenchymal/osteoprogenitor cells are unclear. In 60 multiple myeloma patients checked, we found that among the Wnt inhibitors, Dickkopf-1 and secreted frizzled-related protein-3 were produced by multiple myeloma cells. However, although multiple myeloma cells or multiple myeloma bone marrow plasma affected expression of genes in the canonical Wnt signaling and inhibited beta-catenin stabilization in murine osteoprogenitor cells, they failed to block the canonical Wnt pathway in human mesenchymal or osteoprogenitor cells. Consistently, Wnt3a stimulation in human osteoprogenitor cells did not blunt the inhibitory effect of multiple myeloma cells on osteoblast formation. Consequently, despite the higher Wnt antagonist bone marrow levels in osteolytic multiple myeloma patients compared with nonosteolytic ones, beta-catenin immunostaining was not significantly different. Our results support the link between the production of Wnt antagonists by multiple myeloma cells and the presence of bone lesions in multiple myeloma patients but show that myeloma cells do not inhibit canonical Wnt signaling in human bone microenvironment. Secreted frizzled-related proteins (sFRPs) are secreted glycoproteins involved in neoplastic growth. Four hormones synthesized in the heart, namely vessel dilator, atrial natriuretic peptide (ANP), kaliuretic peptide (KP) and long-acting natriuretic peptide (LANP), have anticancer effects both in vitro and in vivo. These heart hormones were evaluated for their ability to inhibit sFRP-3, which is associated with tumor invasiveness, in human pancreatic cancer, colorectal cancer and renal adenocarcinoma cell lines. Vessel dilator, KP, ANP and LANP maximally reduced the concentration of sFRP-3 by 83%, 83%, 84% and 83%, respectively (each at P<0.0001), in the human colorectal adenocarcinoma cells. In the human pancreatic carcinoma cells, the concentration of sFRP-3 was maximally reduced by 77%, 77%, 77% and 78% (each at P<0.0001) secondary to treatment with vessel dilator, KP, ANP and LANP, respectively. In the human renal adenocarcinoma cells, the sFRP-3 was maximally reduced by vessel dilator, KP, ANP and LANP by 68%, 66%, 68% and 66% (each at P<0.0001), respectively. The results indicate that these four cardiac hormones are significant inhibitors (up to 84%) of sFRP-3 in a variety of human cancer cells. Furthermore, these data suggest that the metabolic targeting of sFRP-3 by the cardiac hormones contributes to their anti-cancer mechanism(s) of action.

Albumin depletion is a common first step for proteomic analysis of CSF fluid. What is the advantage and disadvantage of this procedure?

Depletion of the high abundant protein Albumin from CSF samples is improving the detection of lower abundant proteins but may also lead to the potential loss of non-target proteins.

Glycoproteins in cerebrospinal fluid are found to be altered in Alzheimer patients compared to healthy control individuals. We have utilized micro-solution isoelectric focusing and affinity chromatography, prior to gel electrophoresis to enable site-specific structural determination of the N-linked glycans in apolipoprotein J with the use of FT-ICR MS. The albumin depletion method is the most suitable as prefractionation method of CSF prior to 2-DE for structural determination of glycoproteins in the study of neurodegenerative disorders. Glycoproteins in cerebrospinal fluid (CSF) are altered in Alzheimer's Disease (AD) patients compared to control individuals. We have utilized albumin depletion prior to 2D gel electrophoresis to enhance glycoprotein concentration for image analysis as well as structural glycoprotein determination without glycan release using mass spectrometry (MS). The benefits of a direct glycoprotein analysis approach include minimal sample manipulation and retention of structural details. A quantitative comparison of gel-separated glycoprotein isoforms from twelve AD patients and twelve control subjects was performed with glycoprotein-specific and total protein stains. We have also compared glycoforms in pooled CSF obtained from AD patients and control subjects with mass spectrometry. One isoform of alpha1-antitrypsin showed decreased glycosylation in AD patients while another glycosylated isoform of an unassigned protein was up-regulated. Protein expression levels of alpha1-antitrypsin were decreased, while the protein levels of apolipoprotein E and clusterin were increased in AD. No specific glycoform could be specifically assigned to AD. Various approaches for removal of high-abundance components in body fluids are currently available. While most methods are constructed for plasma depletion, there is a need for body-fluid-specific strategies. The aim of the present study was to design an affinity matrix suitable for the depletion of high-abundance proteins in CSF (cerebrospinal fluid). Hence, molecules with specific affinity towards proteins present at high concentration in CSF were desired. Affibody molecules are specific binders of small size that have shown high stability under various conditions and are therefore good candidates for such a matrix. The protein composition in CSF resembles that in plasma. However, 20% of the proteins are brain-derived and are therefore present in higher proportions in CSF than in plasma, whereas larger plasma-derived proteins are less abundant in CSF. Therefore five high-abundance CSF proteins were chosen for the design of a CSF-specific depletion setup. Affibody molecules with specificity towards HSA (human serum albumin), IgG, transferrin and transthyretin were combined in an affinity column. In addition, polyclonal antibodies against cystatin C were coupled to chromatographic beads and packed in a separate column. Highly reproducible and efficient removal of the five target proteins was observed. The proportion of depleted proteins were estimated to be 99, 95, 74, 92 and 83% for HSA, IgG, transferrin, transthyretin and cystatin C respectively. SDS/PAGE analysis was used for monitoring and identifying proteins in native CSF, depleted CSF samples and the captured fractions. Moreover, shotgun proteomics was used for protein identification in native as well as depleted CSF and the achieved data were compared. Enhanced identification of lower-abundance components was observed in the depleted fraction, in terms of more detected peptides per protein. OBJECTIVES: Two different depletion strategies for removing albumin from human cerebrospinal fluid (CSF), Microcon Centrifugal Filter vs. Montage Albumin Deplete kit, were evaluated for improving protein profiling pattern and reproducibility in SELDI analysis. DESIGN AND METHODS: Pooled CSF was divided into 20 aliquots and these aliquots were subjected to SELDI analysis either after albumin depletion or without preprocessing. Protein profiles were obtained by using CM10, Q10 and IMAC chips. RESULTS: Both strategies resulted in reliable albumin depletion (<6.2 mg/L, filter; 8.1 mg/L, depletion kit). Investigated methods of albumin depletion showed no significant differences in coefficients of variation (CVs) of peak intensities compared to unprocessed CSF on almost all chip types. Peak intensities were significantly higher after albumin depletion compared to CSF without preprocessing on Q10 and on CM10 chips. Nevertheless, the two strategies of albumin depletion led to a decrease in the number of detected peaks on all chip types compared to unprocessed CSF, but several additional peaks, not detected in unprocessed CSF, occurred. CONCLUSIONS: This study demonstrates that reduction of sample complexity by albumin depletion of CSF can be performed without CV impairment. However, the significance of this strategy needs to be evaluated separately for each individual biomarker discovery study. BACKGROUND: In cerebrospinal fluid (CSF), which is a rich source of biomarkers for neurological diseases, identification of biomarkers requires methods that allow reproducible detection of low abundance proteins. It is therefore crucial to decrease dynamic range and improve assessment of protein abundance. RESULTS: We applied LC-MS/MS to compare the performance of two CSF enrichment techniques that immunodeplete either albumin alone (IgYHSA) or 14 high-abundance proteins (IgY14). In order to estimate dynamic range of proteins identified, we measured protein abundance with APEX spectral counting method.Both immunodepletion methods improved the number of low-abundance proteins detected (3-fold for IgYHSA, 4-fold for IgY14). The 10 most abundant proteins following immunodepletion accounted for 41% (IgY14) and 46% (IgYHSA) of CSF protein content, whereas they accounted for 64% in non-depleted samples, thus demonstrating significant enrichment of low-abundance proteins. Defined proteomics experiment metrics showed overall good reproducibility of the two immunodepletion methods and MS analysis. Moreover, offline peptide fractionation in IgYHSA sample allowed a 4-fold increase of proteins identified (520 vs. 131 without fractionation), without hindering reproducibility. CONCLUSIONS: The novelty of this study was to show the advantages and drawbacks of these methods side-to-side. Taking into account the improved detection and potential loss of non-target proteins following extensive immunodepletion, it is concluded that both depletion methods combined with spectral counting may be of interest before further fractionation, when searching for CSF biomarkers. According to the reliable identification and quantitation obtained with APEX algorithm, it may be considered as a cheap and quick alternative to study sample proteomic content.

How are lincRNA affecting the regulation of gene expression?

lincRNA may function either as modulators of epigenetic mark deposition or as endogenous antagonists for microRNA binding. A lincRNA, linc-RoR, may function as a key competing endogenous RNA to link the network of miRNAs and core TFs, e.g., Oct4, Sox2, and Nanog. Mdig is involved in the regulation of H3K9me3 to influence the heterochromatin structure of the genome and the expression of genes important for cell growth or transformation. Observed biases in lincRNA genomic locations and expression profiles are consistent with some of these lincRNAs being involved in the regulation of neighboring protein-coding genes with developmental functions.

Mammalian long intergenic noncoding RNAs (lincRNAs) are best known for modulating transcription. Here we report a posttranscriptional function for lincRNA-p21 as a modulator of translation. Association of the RNA-binding protein HuR with lincRNA-p21 favored the recruitment of let-7/Ago2 to lincRNA-p21, leading to lower lincRNA-p21 stability. Under reduced HuR levels, lincRNA-p21 accumulated in human cervical carcinoma HeLa cells, increasing its association with JUNB and CTNNB1 mRNAs and selectively lowering their translation. With elevated HuR, lincRNA-p21 levels declined, which in turn derepressed JunB and β-catenin translation and increased the levels of these proteins. We propose that HuR controls translation of a subset of target mRNAs by influencing lincRNA-p21 levels. Our findings uncover a role for lincRNA as a posttranscriptional inhibitor of translation. The embryonic stem cell (ESC) transcriptional and epigenetic networks are controlled by a multilayer regulatory circuitry, including core transcription factors (TFs), posttranscriptional modifier microRNAs (miRNAs), and some other regulators. However, the role of large intergenic noncoding RNAs (lincRNAs) in this regulatory circuitry and their underlying mechanism remains undefined. Here, we demonstrate that a lincRNA, linc-RoR, may function as a key competing endogenous RNA to link the network of miRNAs and core TFs, e.g., Oct4, Sox2, and Nanog. We show that linc-RoR shares miRNA-response elements with these core TFs and that linc-RoR prevents these core TFs from miRNA-mediated suppression in self-renewing human ESC. We suggest that linc-RoR forms a feedback loop with core TFs and miRNAs to regulate ESC maintece and differentiation. These results may provide insights into the functional interactions of the components of genetic networks during development and may lead to new therapies for many diseases. Large intergenic noncoding (linc) RNAs constitute a new dimension of posttranscriptional gene regulation. In this issue of Developmental Cell, Wang et al. (2013) find that linc-RoR maintains human embryonic stem cell self-renewal by functioning as a sponge to trap miR-145, thus regulating core pluripotency factors Oct4, Nanog, and Sox2. Hotair is a member of the recently described class of noncoding RNAs called lincRNA (large intergenic noncoding RNA). Various studies suggest that Hotair acts regulating epigenetic states by recruiting chromatin-modifying complexes to specific target sequences that ultimately leads to suppression of several genes. Although Hotair has been associated with metastasis and poor prognosis in different tumor types, a deep characterization of its functions in cancer is still needed. Here, we investigated the role of Hotair in the scenario of epithelial-to-mesenchymal transition (EMT) and in the arising and maintece of cancer stem cells (CSCs). We found that treatment with TGF-β1 resulted in increased Hotair expression and triggered the EMT program. Interestingly, ablation of Hotair expression by siRNA prevented the EMT program stimulated by TGF-β1, and also the colony-forming capacity of colon and breast cancer cells. Furthermore, we observed that the colon CSC subpopulation (CD133(+)/CD44(+)) presents much higher levels of Hotair when compared with the non-stem cell subpopulation. These results indicate that Hotair acts as a key regulator that controls the multiple signaling mechanisms involved in EMT. Altogether, our data suggest that the role of Hotair in tumorigenesis occurs through EMT triggering and stemness acquisition. Large intergenic noncoding RNAs (lincRNAs) are still poorly functionally characterized. We analyzed the genetic and epigenetic regulation of human lincRNA expression in the GenCord collection by using three cell types from 195 unrelated European individuals. We detected a considerable number of cis expression quantitative trait loci (cis-eQTLs) and demonstrated that the genetic regulation of lincRNA expression is independent of the regulation of neighboring protein-coding genes. lincRNAs have relatively more cis-eQTLs than do equally expressed protein-coding genes with the same exon number. lincRNA cis-eQTLs are located closer to transcription start sites (TSSs) and their effect sizes are higher than cis-eQTLs found for protein-coding genes, suggesting that lincRNA expression levels are less constrained than that of protein-coding genes. Additionally, lincRNA cis-eQTLs can influence the expression level of nearby protein-coding genes and thus could be considered as QTLs for enhancer activity. Enrichment of expressed lincRNA promoters in enhancer marks provides an additional argument for the involvement of lincRNAs in the regulation of transcription in cis. By investigating the epigenetic regulation of lincRNAs, we observed both positive and negative correlations between DNA methylation and gene expression (expression quantitative trait methylation [eQTMs]), as expected, and found that the landscapes of passive and active roles of DNA methylation in gene regulation are similar to protein-coding genes. However, lincRNA eQTMs are located closer to TSSs than are protein-coding gene eQTMs. These similarities and differences in genetic and epigenetic regulation between lincRNAs and protein-coding genes contribute to the elucidation of potential functions of lincRNAs. Hypoxia has long been linked to the Warburg effect, yet the underlying mechanism remains largely unclear. It is also not known if lncRNAs are involved in the contribution of hypoxia to the Warburg effect. Here we show that lincRNA-p21 is a hypoxia-responsive lncRNA and is essential for hypoxia-enhanced glycolysis. Hypoxia/HIF-1α-induced lincRNA-p21 is able to bind HIF-1α and VHL and thus disrupts the VHL-HIF-1α interaction. This disassociation attenuates VHL-mediated HIF-1α ubiquitination and causes HIF-1α accumulation. These data indicate the existence of a positive feedback loop between HIF-1α and lincRNA-p21 that promotes glycolysis under hypoxia. The ability of lincRNA-p21 to promote tumor growth is validated in mouse xenograft models. Together, these findings suggest that lincRNA-p21 is an important player in the regulation of the Warburg effect and also implicate lincRNA-p21 as a valuable therapeutic target for cancer.