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Pancreatic ductal adenocarcinoma (PDA) is a fatal and insidious malignant disease for which clinicians’ tools are restricted by the current limits in knowledge of how tumor and stromal cells act during the disease. Among PDA hallmarks, neural remodeling (NR) and perineural invasion (PNI) drastically influence quality of life and patient survival. Indeed, NR and PNI are associated with neuropathic pain and metastasis, respectively, both of which impact clinicians’ decisions and therapeutic options. The aim of this study was to determine the impact and clinical relevance of the peritumoral microenvironment, through pancreatitis-associated protein (PAP/REG3A) expression, on PNI in pancreatic cancer. First, we demonstrated that, in PDA, PAP/REG3A is produced by inflamed acinar cells from the peritumoral microenvironment and then enhances the migratory and invasive abilities of cancer cells. More specifically, using perineural ex vivo assays we revealed that PAP/REG3A favors PNI through activation of the JAK/STAT signaling pathway in cancer cells. Finally, we analyzed the level of PAP/REG3A in blood from healthy donors or patients with PDA from three independent cohorts. Patients with high levels of PAP/REG3A had overall shorter survival as well as poor surgical outcomes with reduced disease-free survival. Our study provides a rationale for using the PAP/REG3A level as a biomarker to improve pancreatic cancer prognosis. It also suggests that therapeutic targeting of PAP/REG3A activity in PDA could limit tumor cell aggressiveness and PNI.  相似文献   
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We report a genome-wide association study for melanoma that was conducted by the GenoMEL Consortium. Our discovery phase included 2,981 individuals with melanoma and 1,982 study-specific control individuals of European ancestry, as well as an additional 6,426 control subjects from French or British populations, all of whom were genotyped for 317,000 or 610,000 single-nucleotide polymorphisms (SNPs). Our analysis replicated previously known melanoma susceptibility loci. Seven new regions with at least one SNP with P < 10(-5) and further local imputed or genotyped support were selected for replication using two other genome-wide studies (from Australia and Texas, USA). Additional replication came from case-control series from the UK and The Netherlands. Variants at three of the seven loci replicated at P < 10(-3): an SNP in ATM (rs1801516, overall P = 3.4 × 10(-9)), an SNP in MX2 (rs45430, P = 2.9 × 10(-9)) and an SNP adjacent to CASP8 (rs13016963, P = 8.6 × 10(-10)). A fourth locus near CCND1 remains of potential interest, showing suggestive but inconclusive evidence of replication (rs1485993, overall P = 4.6 × 10(-7) under a fixed-effects model and P = 1.2 × 10(-3) under a random-effects model). These newly associated variants showed no association with nevus or pigmentation phenotypes in a large British case-control series.  相似文献   
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Schizophrenia is a severe psychiatric disorder that profoundly affects cognitive, behavioral and emotional processes. The wide spectrum of symptoms and clinical variability in schizophrenia suggest a complex genetic etiology, which is consistent with the numerous loci thus far identified by linkage, copy number variation and association studies. Although schizophrenia heritability may be as high as ~80%, the genes responsible for much of this heritability remain to be identified. Here we sequenced the exomes of 14 schizophrenia probands and their parents. We identified 15 de novo mutations (DNMs) in eight probands, which is significantly more than expected considering the previously reported DNM rate. In addition, 4 of the 15 identified DNMs are nonsense mutations, which is more than what is expected by chance. Our study supports the notion that DNMs may account for some of the heritability reported for schizophrenia while providing a list of genes possibly involved in disease pathogenesis.  相似文献   
165.
We estimate and partition genetic variation for height, body mass index (BMI), von Willebrand factor and QT interval (QTi) using 586,898 SNPs genotyped on 11,586 unrelated individuals. We estimate that ~45%, ~17%, ~25% and ~21% of the variance in height, BMI, von Willebrand factor and QTi, respectively, can be explained by all autosomal SNPs and a further ~0.5-1% can be explained by X chromosome SNPs. We show that the variance explained by each chromosome is proportional to its length, and that SNPs in or near genes explain more variation than SNPs between genes. We propose a new approach to estimate variation due to cryptic relatedness and population stratification. Our results provide further evidence that a substantial proportion of heritability is captured by common SNPs, that height, BMI and QTi are highly polygenic traits, and that the additive variation explained by a part of the genome is approximately proportional to the total length of DNA contained within genes therein.  相似文献   
166.
Interleukin 7 (IL-7) and its receptor, formed by IL-7Rα (encoded by IL7R) and γc, are essential for normal T-cell development and homeostasis. Here we show that IL7R is an oncogene mutated in T-cell acute lymphoblastic leukemia (T-ALL). We find that 9% of individuals with T-ALL have somatic gain-of-function IL7R exon 6 mutations. In most cases, these IL7R mutations introduce an unpaired cysteine in the extracellular juxtamembrane-transmembrane region and promote de novo formation of intermolecular disulfide bonds between mutant IL-7Rα subunits, thereby driving constitutive signaling via JAK1 and independently of IL-7, γc or JAK3. IL7R mutations induce a gene expression profile partially resembling that provoked by IL-7 and are enriched in the T-ALL subgroup comprising TLX3 rearranged and HOXA deregulated cases. Notably, IL7R mutations promote cell transformation and tumor formation. Overall, our findings indicate that IL7R mutational activation is involved in human T-cell leukemogenesis, paving the way for therapeutic targeting of IL-7R-mediated signaling in T-ALL.  相似文献   
167.
Fertility is one of the key components of the national population projections, alongside mortality and migration. For the 2006-based population projections, long-term completed family size in the U.K. is assumed to be 1.84 children per woman. This represents an increase of 0.10 on the assumption of 1.74 children per woman used in the 2004-based round. Although the U.K's long-term fertilit assumption has been lowered several time in recent years, this is the first time it has been raised since the 1960s baby boom. This article outlines why ONS decided to raise the long-term fertility assumptio for all four U.K. countries in the 2006-based population projections  相似文献   
168.
We conducted a genome-wide SNP association study on prostate cancer on over 23,000 Icelanders, followed by a replication study including over 15,500 individuals from Europe and the United States. Two newly identified variants were shown to be associated with prostate cancer: rs5945572 on Xp11.22 and rs721048 on 2p15 (odds ratios (OR) = 1.23 and 1.15; P = 3.9 x 10(-13) and 7.7 x 10(-9), respectively). The 2p15 variant shows a significantly stronger association with more aggressive, rather than less aggressive, forms of the disease.  相似文献   
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