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991.
Genome-wide association studies of case-control status have advanced the understanding of the genetic basis of psychiatric disorders. Further progress may be gained by increasing sample size but also by new analysis strategies that advance the exploitation of existing data, especially for clinically important quantitative phenotypes. The functionally-informed efficient region-based test strategy (FIERS) introduced herein uses prior knowledge on biological function and dependence of genotypes within a powerful statistical framework with improved sensitivity and specificity for detecting consistent genetic effects across studies. As proof of concept, FIERS was used for the first genome-wide single nucleotide polymorphism (SNP)-based investigation on bipolar disorder (BD) that focuses on an important aspect of disease course, the functional outcome. FIERS identified a significantly associated locus on chromosome 15 (hg38: chr15:48965004 – 49464789 bp) with consistent effect strength between two independent studies (GAIN/TGen: European Americans, BOMA: Germans; n?=?1592 BD patients in total). Protective and risk haplotypes were found on the most strongly associated SNPs. They contain a CTCF binding site (rs586758); CTCF sites are known to regulate sets of genes within a chromatin domain. The rs586758 – rs2086256 – rs1904317 haplotype is located in the promoter flanking region of the COPS2 gene, close to microRNA4716, and the EID1, SHC4, DTWD1 genes as plausible biological candidates. While implication with BD is novel, COPS2, EID1, and SHC4 are known to be relevant for neuronal differentiation and function and DTWD1 for psychopharmacological side effects. The test strategy FIERS that enabled this discovery is equally applicable for tag SNPs and sequence data.  相似文献   
992.
Although previous studies on tobacco and alcohol and the risk of upper‐aerodigestive‐tract (UADT) cancers have clearly shown dose‐response relations with the frequency and duration of tobacco and alcohol, studies on addiction to tobacco smoking itself as a risk factor for UADT cancer have not been published, to our knowledge. The aim of this report is to assess whether smoking addiction is an independent risk factor or a refinement to smoking variables (intensity and duration) for UADT squamous cell carcinoma (SCC) risk in the multicenter case–control study (ARCAGE) in Western Europe. The analyses included 1,586 ever smoking UADT SCC cases and 1,260 ever smoking controls. Addiction was measured by a modified Fagerström score (first cigarette after waking up, difficulty refraining from smoking in places where it is forbidden and cigarettes per day). Adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for UADT cancers with addiction variables were estimated with unconditional logistic regression. Among current smokers, the participants who smoked their first cigarette within 5 min of waking up were two times more likely to develop UADT SCC than those who smoked 60 min after waking up. Greater tobacco smoking addiction was associated with an increased risk of UADT SCC among current smokers (OR = 3.83, 95% CI: 2.56–5.73 for score of 3–7 vs. 0) but not among former smokers. These results may be consistent with a residual effect of smoking that was not captured by the questionnaire responses (smoking intensity and smoking duration) alone, suggesting addiction a refinement to smoking variables.  相似文献   
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995.
A hallmark of renal cell carcinoma (RCC) invasion is its ability to degrade ECM by local production of gelatinase enzymes. Although many studies on RCC have demonstrated the importance of MMPs, very little information is currently known regarding the effect of inducers and inhibitors. We therefore investigated the effect of inducers and inhibitors on RCC 786-0 in vitro. Human RCC 786-0 (ATCC) was grown in RPMI medium supplemented with 10% FBS, penicillin, and streptomycin in 24-well tissue plates. At near confuence, the cells were washed with PBS; the serum-free medium was incubated with various inducers: phorbol ester (PMA), tumor necrosis factor alpha (TNF-α), interleukin 1-beta (IL-β) and lipopolysaccharides (LPS). Cells were also incubated with inhibitors: EGCG, doxycycline, and a nutrient mixture with and without PMA; retinoic acid, dexamethasone, H-7; actinomcin D, or cyclohexamide. After 24 h, the medium was removed and analyzed for MMP-2 and MMP-9 by gelatinase zymography. RCC 786-0 secreted two bands, a major band corresponding to MMP-2 and a faint band corresponding to MMP-9. PMA and TNF-α, with increased concentration, increased MMP-9 secretion, while IL-1β and LPS did not significantly modify MMP-9 activity. MMP-2 secretion was not affected by any of the inducers. All the inhibitors tested without and with PMA showed a dose-dependent decrease in both MMP-2 and-9 expression. Further studies are in progress to confirm the role of MMP-9 on Matrigel invasion using PMA, cytokines, and LPS.  相似文献   
996.
Head and neck cancer (HNC) is a preventable malignancy that continues to cause substantial morbidity and mortality worldwide. Using data from the ARCAGE and Rome studies, we investigated the main predictors of survival after larynx, hypopharynx and oral cavity (OC) cancers. We used the Kaplan–Meier method to estimate overall survival, and Cox proportional models to examine the relationship between survival and sociodemographic and clinical characteristics. 604 larynx, 146 hypopharynx and 460 OC cancer cases were included in this study. Over a median follow‐up time of 4.6 years, nearly 50% (n = 586) of patients died. Five‐year survival was 65% for larynx, 55% for OC and 35% for hypopharynx cancers. In a multivariable analysis, we observed an increased mortality risk among older (≥71 years) versus younger (≤50 years) patients with larynx/hypopharynx combined (LH) and OC cancers [HR = 1.61, 95% CI 1.09–2.38 (LH) and HR = 2.12, 95% CI 1.35–3.33 (OC)], current versus never smokers [HR = 2.67, 95% CI 1.40–5.08 (LH) and HR = 2.16, 95% CI 1.32–3.54 (OC)] and advanced versus early stage disease at diagnosis [IV versus I, HR = 2.60, 95% CI 1.78–3.79 (LH) and HR = 3.17, 95% CI 2.05–4.89 (OC)]. Survival was not associated with sex, alcohol consumption, education, oral health, p16 expression, presence of HPV infection or body mass index 2 years before cancer diagnosis. Despite advances in diagnosis and therapeutic modalities, survival after HNC remains low in Europe. In addition to the recognized prognostic effect of stage at diagnosis, smoking history and older age at diagnosis are important prognostic indicators for HNC.  相似文献   
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998.
Cell adhesion, proteolytic degradation and cell migration are interrelated processes responsible for the invasion and metastasis of cancer. One of the crucial molecules involved in cancer metastasis is urokinase-type plasminogen activator (uPA). An elevated concentration of uPA is a strong indicator of poor prognosis. In addition to the proteolytic activity of uPA, which degrades the extracellular matrix, uPA also binds to its receptor (uPAR) and controls cell adhesion and migration through the reorganization of actin cytoskeleton. We have recently demonstrated that constitutively active nuclear factor-kappa B (NF-kappaB) is responsible for the increased secretion of uPA and that inhibition of NF-kappaB suppresses secretion of uPA and cell migration of highly invasive cancer cells. Aspirin and other nonsteroidal anti-inflammatory drugs have been recently shown to have a chemopreventive effect in colon and pancreatic cancers. Here we show that aspirin inhibits NF-kappaB, resulting in the suppression of uPA secretion from the highly invasive human prostate cancer cells PC-3. Furthermore, aspirin inhibited migration of PC-3 cells, suggesting an effect on the uPA-uPAR signaling complex. Finally, aspirin suppressed adhesion of PC-3 cells to fibronectin (FN), which binds to an alpha3beta1 integrin receptor, and to vitronectin (VN), which binds to alphavbeta3 integrin receptor. Altogether, our data suggests that aspirin inhibits the formation of uPA-uPAR-FN-alpha3beta1 and uPA-uPAR-VN-alphavbeta3 complexes, resulting in the suppression of cell adhesion and cell motility of the highly invasive prostate cancer cells PC-3. These results indicate that aspirin may contribute directly to reducing invasion and metastasis of prostate cancers by inhibiting cell migration and invasion.  相似文献   
999.
Inflammation, which includes the release of growth factors, proinflammatory cytokines and prostaglandins, the infiltration and activation of inflammatory cells, and the induction of oxidative DNA damage, is known to play a role in cancer development. The combination of damage to the skin resulting from chronic ultraviolet light B (UVB) exposure itself and the inflammatory response it induces is a major source of skin cancer development. Cyclooxygenase-2 (COX-2), an inflammatory enzyme responsible for the production of prostaglandins, is now implicated in the development of epithelial cancers, including squamous cell carcinoma in the skin. Previous work conducted in our laboratory has shown that topical treatment with celecoxib following UVB irradiation inhibits several parameters of acute inflammation, including vascular permeability, the infiltration and activation of neutrophils, and the production of prostaglandin E(2) (PGE(2)). The present studies expanded these observations, demonstrating the ability of topical celecoxib to inhibit acute oxidative damage. In addition, long-term studies illustrate the effectiveness of topical treatment with this drug in reducing chronic inflammation and UVB-induced papilloma/carcinoma formation. This data provides compelling evidence to explore the clinical efficacy of topically applied COX-2 inhibitors for the prevention of human skin cancers.  相似文献   
1000.
BCR/ABL activates mdm2 mRNA translation via the La antigen   总被引:9,自引:0,他引:9  
In a BCR/ABL-expressing myeloid precursor cell line, p53 levels were markedly downmodulated. Expression of MDM2, the negative regulator of p53, was upregulated in a tyrosine kinase-dependent manner in growth factor-independent BCR/ABL-expressing cells, and in accelerated phase and blast crisis CML samples. Increased MDM2 expression was associated with enhanced mdm2 mRNA translation, which required the interaction of the La antigen with mdm2 5' UTR. Expression of MDM2 correlated with that of La and was suppressed by La siRNAs and by a dominant negative La mutant, which also enhanced the susceptibility to drug-induced apoptosis of BCR/ABL-transformed cells. By contrast, La overexpression led to increased MDM2 levels and enhanced resistance to apoptosis. Thus, La-dependent activation of mdm2 translation might represent an important molecular mechanism involved in BCR/ABL leukemogenesis.  相似文献   
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