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971.
Yoffou PH Edjekouane L Meunier L Tremblay A Provencher DM Mes-Masson AM Carmona E 《PloS one》2011,6(6):e20705
Background
Epithelial ovarian cancer (EOC) is morphologically heterogeneous being classified as serous, endometrioid, clear cell, or mucinous. Molecular genetic analysis has suggested a role for tumor suppressor genes located at chromosome 3p in serous EOC pathogenesis. Our objective was to evaluate the expression of HYAL1, located at chromosome 3p21.3, in these EOC subtypes, and to investigate its correlation with the expression of steroid hormone receptors.Methodology/Principal Findings
We determined the mRNA expression of HYAL1, estrogen receptor (ER)-α, ERβ and progesterone receptor (PR) in EOC tumor samples and cell lines using quantitative RT-PCR. We also examined the expression of these genes in a publicly available microarray dataset. HYAL-1 enzyme activity was measured in EOC cell lines and in plasma samples from patients. We found that HYAL1 mRNA expression was elevated in clear cell and mucinous EOC tissue samples, but not in serous and endometrioid samples, normal ovaries or benign tumors. Similar results were obtained by two different techniques and with tissue sample cohorts from two independent institutions. Concordantly, HYAL1 mRNA levels and enzymatic activity were elevated only in EOC cell lines derived from clear cell and mucinous subtypes. We also showed that HYAL1 mRNA was inversely correlated to that of ERα specifically in clear cell and mucinous EOCs. Additionally, ectopic expression of ERα in a clear cell EOC cell line (ER- and PR-negative) induced 50% reduction of HYAL1 mRNA expression, supporting a role of ERα in HYAL1 gene regulation. Significantly, HYAL-1 activity was also high in the plasma of patients with these EOC subtypes.Conclusions/Significance
This is the first report showing high HYAL-1 levels in EOC and demonstrating HYAL1 gene repression by ERα. Our results identify Hyaluronidase-1 as a potential target/biomarker for clear cell and mucinous EOCs and especially in tumors with low ERα levels. 相似文献972.
Background
Angiogenesis may play a role in the pathogenesis of Non-Small Cell Lung cancer (NSCLC). The CXC (ELR+) chemokine family are powerful promoters of the angiogenic response.Methods
The expression of the CXC (ELR+) family members (CXCL1-3/GROα-γ, CXCL8/IL-8, CXCR1/2) was examined in a series of resected fresh frozen NSCLC tumours. Additionally, the expression and epigenetic regulation of these chemokines was examined in normal bronchial epithelial and NSCLC cell lines.Results
Overall, expression of the chemokine ligands (CXCL1, 2, 8) and their receptors (CXCR1/2) were down regulated in tumour samples compared with normal, with the exception of CXCL3. CXCL8 and CXCR1/2 were found to be epigenetically regulated by histone post-translational modifications. Recombinant CXCL8 did not stimulate cell growth in either a normal bronchial epithelial or a squamous carcinoma cell line (SKMES-1). However, an increase was observed at 72 hours post treatment in an adenocarcinoma cell line.Conclusions
CXC (ELR+) chemokines are dysregulated in NSCLC. The balance of these chemokines may be critical in the tumour microenvironment and requires further elucidation. It remains to be seen if epigenetic targeting of these pathways is a viable therapeutic option in lung cancer treatment. 相似文献973.
Germain M Saut N Greliche N Dina C Lambert JC Perret C Cohen W Oudot-Mellakh T Antoni G Alessi MC Zelenika D Cambien F Tiret L Bertrand M Dupuy AM Letenneur L Lathrop M Emmerich J Amouyel P Trégouët DA Morange PE 《PloS one》2011,6(9):e25581
Background
Venous Thrombosis (VT) is a common multifactorial disease associated with a major public health burden. Genetics factors are known to contribute to the susceptibility of the disease but how many genes are involved and their contribution to VT risk still remain obscure. We aimed to identify genetic variants associated with VT risk.Methodology/Principal Findings
We conducted a genome-wide association study (GWAS) based on 551,141 SNPs genotyped in 1,542 cases and 1,110 controls. Twelve SNPs reached the genome-wide significance level of 2.0×10−8 and encompassed four known VT-associated loci, ABO, F5, F11 and FGG. By means of haplotype analyses, we also provided novel arguments in favor of a role of HIVEP1, PROCR and STAB2, three loci recently hypothesized to participate in the susceptibility to VT. However, no novel VT-associated loci came out of our GWAS. Using a recently proposed statistical methodology, we also showed that common variants could explain about 35% of the genetic variance underlying VT susceptibility among which 3% could be attributable to the main identified VT loci. This analysis additionally suggested that the common variants left to be identified are not uniformly distributed across the genome and that chromosome 20, itself, could contribute to ∼7% of the total genetic variance.Conclusions/Significance
This study might also provide a valuable source of information to expand our understanding of biological mechanisms regulating quantitative biomarkers for VT. 相似文献974.
Philippe Duquesnoy Laetitia Vincensini Judy Freshour André Coste Jacques de Blic Guy Montantin Anne-Marie Vojtek Annick Clément Philippe Bastin Serge Amselem 《American journal of human genetics》2009,85(6):890-4219
Cilia and flagella are evolutionarily conserved structures that play various physiological roles in diverse cell types. Defects in motile cilia result in primary ciliary dyskinesia (PCD), the most prominent ciliopathy, characterized by the association of respiratory symptoms, male infertility, and, in nearly 50% of cases, situs inversus. So far, most identified disease-causing mutations involve genes encoding various ciliary components, such those belonging to the dynein arms that are essential for ciliary motion. Following a candidate-gene approach based on data from a mutant strain of the biflagellated alga Chlamydomonas reinhardtii carrying an ODA7 defect, we identified four families with a PCD phenotype characterized by the absence of both dynein arms and loss-of-function mutations in the human orthologous gene called LRRC50. Functional analyses performed in Chlamydomonas reinhardtii and in another flagellated protist, Trypanosoma brucei, support a key role for LRRC50, a member of the leucine-rich-repeat superfamily, in cytoplasmic preassembly of dynein arms. 相似文献
975.
Effect of Sub-deficient Zinc Status on Insulin Sensitivity after Burn Injury in Rats 总被引:1,自引:0,他引:1
Claeyssen R Andriollo-Sanchez M Arnaud J Touvard L Alonso A Chancerelle Y Roussel AM Agay D 《Biological trace element research》2009,127(2):132-142
Although zinc status is an important parameter in insulin sensitivity, data concerning its implication in noxious burn-induced
insulin resistance are scarce. The present study was designed to evaluate the impact of zinc status before burn on the recovery
of injury with focus on plasma insulin and glucose levels. The experiment was performed in male adult Wistar rats fed from
weaning with a zinc normal diet (80 ppm) or a depleted zinc diet (10 ppm) for 8 weeks and burned to third degree on 20% of
their total body surface area. Blood and tissue samples were collected 3, 6, and 24 h after injury in order to study biochemical
parameters and the glucose/insulin response in relation with the zinc status. After burn, zinc-depleted rats presented an
exacerbated decrease in plasma zinc level. In addition, the burn-induced insulin resistance, leading to protein catabolism,
was emphasized, with higher plasma insulin, glucose, and leptin levels in zinc-deficient animals versus normal-fed rats. Our
experimental results underlined the interest to early control the zinc status in order to limit the deleterious effects of
oxidative stress and insulin resistance in burned patients. 相似文献
976.
977.
AM Hutchinson N Batra-Garga L Cranley AM Bostrom G Cummings P Norton CA Estabrooks 《Implementation science : IS》2012,7(1):89
ABSTRACT: BACKGROUND: This project occurred during the course of the Translating Research in Elder Care (TREC) program of research. TREC is a multilevel and longitudinal research program being conducted in the three Canadian Prairie Provinces of Alberta, Saskatchewan, and Manitoba. The main purpose of TREC is to increase understanding about the role of organizational context in influencing knowledge use in residential long-term care settings. The purpose of this study was to evaluate healthcare aides' (HCAs) perceptions of a one-page poster designed to feed back aggregated data (including demographic information and perceptions about influences on best practice) from the TREC survey they had recently completed. METHODS: A convenience sample of 7 of the 15 nursing homes participating in the TREC research program in Alberta were invited to participate. Specific facility-level summary data were provided to each facility in the form of a one-page poster report. Two weeks following delivery of the report, a convenience sample of HCAs was surveyed using one-to-one structured interviews. RESULTS: One hundred twenty-three HCAs responded to the evaluation survey. Overall, HCAs' opinions about presentation of the feedback report and the understandability, usability, and usefulness of the content were positive. For each report, analysis of data and production and inspection of the report took up to one hour. Information sessions to introduce and explain the reports averaged 18 minutes. Two feedback reports (minimum) were supplied to each facility at a cost of CAN$2.39 per report, for printing and laminating. CONCLUSIONS: This study highlights not only the feasibility of producing understandable, usable, and useful feedback reports of survey data but also the value and importance of providing feedback to survey respondents. More broadly, the findings suggest that modest strategies may have a positive and desirable effect in participating sites. 相似文献
978.
Marchal C Vinatier G Sanial M Plessis A Pret AM Limbourg-Bouchon B Théodore L Netter S 《PloS one》2012,7(3):e34310
The genome of the human immunodeficiency virus type 1 (HIV-1) encodes the canonical retroviral proteins, as well as additional accessory proteins that enhance the expression of viral genes, the infectivity of the virus and the production of virions. The accessory Viral Protein U (Vpu), in particular, enhances viral particle production, while also promoting apoptosis of HIV-infected human T lymphocytes. Some Vpu effects rely on its interaction with the ubiquitin-proteasome protein degradation system, but the mechanisms responsible for its pro-apoptotic effects in vivo are complex and remain largely to be elucidated.We took advantage of the Drosophila model to study the effects of Vpu activity in vivo. Expression of Vpu in the developing Drosophila wing provoked tissue loss due to caspase-dependent apoptosis. Moreover, Vpu induced expression of the pro-apoptotic gene reaper, known to down-regulate Inhibitor of Apoptosis Proteins (IAPs) which are caspase-antagonizing E3 ubiquitin ligases. Indeed, Vpu also reduced accumulation of Drosophila IAP1 (DIAP1). Though our results demonstrate a physical interaction between Vpu and the proteasome-addressing SLIMB/β-TrCP protein, as in mammals, both SLIMB/βTrCP-dependent and -independent Vpu effects were observed in the Drosophila wing. Lastly, the pro-apoptotic effect of Vpu in this tissue was abrogated upon inactivation of the c-Jun N-terminal Kinase (JNK) pathway. Our results in the fly thus provide the first functional evidence linking Vpu pro-apoptotic effects to activation of the conserved JNK pathway. 相似文献
979.
MA Forget Y Huon A Reuben C Grange M Liberman J Martin AM Mes-Masson N Arbour R Lapointe 《PloS one》2012,7(7):e41074
Cancer can be treated by adoptive cell transfer (ACT) of T lymphocytes. However, how to optimally raise human T cells to a differentiation state allowing the best persistence in ACT is a challenge. It is possible to differentiate mouse CD8+ T cells towards stem cell-like memory (TSCM) phenotype upon TCR stimulation with Wnt/ß-catenin pathway activation. Here, we evaluated if TSCM can be obtained from human mature CD8+ T cells following TCR and Wnt/ß-catenin activation through treatment with the chemical agent 4,6-disubstituted pyrrolopyrimidine (TWS119), which inhibits the glycogen synthase kinase-3β (GSK-3β), key inhibitor of the Wnt pathway. Human CD8+ T cells isolated from peripheral blood or tumor-infiltrating lymphocytes (TIL), and treated with TWS119 gave rise to CD62L+CD45RA+ cells, indicative of early differentiated stage, also expressing CD127 which is normally found on memory cells, and CD133, an hematopoietic stem cell marker. TSCM cells raised from either TIL or blood secreted numerous inflammatory mediators, but in lower amounts than those measured without TWS119. Finally, generated TSCM CD8+ T cells expressed elevated Bcl-2 and no detectable caspase-3 activity, suggesting increased persistence. Our data support a role for Wnt/ß-catenin pathway in promoting the TSCM subset in human CD8+ T cells from TIL and the periphery, which are relevant for ACT. 相似文献
980.
MN Laguë R Romieu-Mourez E Bonneil A Boyer N Pouletty AM Mes-Masson P Thibault MÈ Nadeau D Boerboom 《PloS one》2012,7(8):e42470
The initial aim of this study was to identify novel serum diagnostic markers for the human ovarian granulosa cell tumor (GCT), a tumor that represents up to 5% of all ovarian cancers. To circumvent the paucity of human tissues available for analyses, we used the Ctnnb1(tm1Mmt/+);Pten(tm1Hwu/tmiHwu);Amhr2(tm3(cre)Bhr/+) transgenic mouse model, which features the constitutive activation of CTNNB1 signaling combined with the loss of Pten in granulosa cells and develops GCTs that mimic aggressive forms of the human disease. Proteomic profiling by mass spectrometry showed that vinculin, enolase 1, several heat shock proteins, and valosin containing protein (VCP) were more abundantly secreted by cultured mouse GCT cells compared to primary cultured GC. Among these proteins, only VCP was present in significantly increased levels in the preoperative serum of GCT cancer patients compared to normal subjects. To determine the specificity of VCP, serum levels were also measured in ovarian carcinoma, non-Hodgkin's lymphoma and breast, colon, pancreatic, lung, and prostate cancer patients. Increased serum VCP levels were observed in the majority of cancer cases, with the exception of patients with lung or prostate cancer. Moreover, serum VCP levels were increased in some GCT, ovarian carcinoma, breast cancer, and colon cancer patients who did not otherwise display increased levels of widely used serum tumor markers for their cancer type (e.g. inhibin A, inhibin B, CA125, CEA, or CA15.3). These results demonstrate the potential use of VCP as highly sensitive serum marker for GCT as well as several other human cancers. 相似文献