Search

Genome-wide association studies (GWAS) have identified ten loci harboring common variants that influence risk of developing colorectal cancer (CRC). To enhance the power to identify additional CRC risk loci, we conducted a meta-analysis of three GWAS from the UK which included a total of 3,334 affected individuals (cases) and 4,628 controls followed by multiple validation analyses including a total of 18,095 cases and 20,197 controls. We identified associations at four new CRC risk loci: 1q41 (rs6691170, odds ratio (OR) = 1.06, P = 9.55 × 10⁻¹⁰ and rs6687758, OR = 1.09, P = 2.27 × 10⁻⁹, 3q26.2 (rs10936599, OR = 0.93, P = 3.39 × 10⁻⁸), 12q13.13 (rs11169552, OR = 0.92, P = 1.89 × 10⁻¹⁰ and rs7136702, OR = 1.06, P = 4.02 × 10⁻⁸) and 20q13.33 (rs4925386, OR = 0.93, P = 1.89 × 10⁻¹⁰). In addition to identifying new CRC risk loci, this analysis provides evidence that additional CRC-associated variants of similar effect size remain to be discovered.

In this present study, the effects of polyacrylonitrile fibres and high content (50%) of Reclaimed Asphalt Pavement (RAP) on the mechanical properties of asphalt mixtures in binder and base layers were studied. This is the first time that the effect of high RAP content on the mechanical properties of fibre reinforced asphalt mixtures (FRAM) was evaluated, while the low temperature performance was not usually conducted in previous studies. Results indicated that the addition of polyacrylonitrile fibres worsens the moisture susceptibility resistance, but improves the rutting, stiffness properties, fatigue performances, and cumulative fatigue damage of the mixtures with and without RAP. No significant effects on the low temperature cracking resistance were found when fibre was used, while a remarkable improvement in the crack propagation resistance properties was observed. Therefore, the use of polyacrylonitrile fibres improves in general the mechanical responses of the mixture, especially in the stiffness response. [ABSTRACT FROM AUTHOR]

Background Various risk factors have been associated with epithelial ovarian cancer risk in observational epidemiological studies. However, the causal nature of the risk factors reported, and thus their suitability as effective intervention targets, is unclear given the susceptibility of conventional observational designs to residual confounding and reverse causation. Mendelian randomization (MR) uses genetic variants as proxies for risk factors to strengthen causal inference in observational studies. We used MR to evaluate the association of 12 previously reported risk factors (reproductive, anthropometric, clinical, lifestyle, and molecular factors) with risk of invasive epithelial ovarian cancer, invasive epithelial ovarian cancer histotypes, and low malignant potential tumours. Methods and findings Genetic instruments to proxy 12 risk factors were constructed by identifying single nucleotide polymorphisms (SNPs) that were robustly (P < 5 x 10.sup.-8) and independently associated with each respective risk factor in previously reported genome-wide association studies. These risk factors included genetic liability to 3 factors (endometriosis, polycystic ovary syndrome, type 2 diabetes) scaled to reflect a 50% higher odds liability to disease. We obtained summary statistics for the association of these SNPs with risk of overall and histotype-specific invasive epithelial ovarian cancer (22,406 cases; 40,941 controls) and low malignant potential tumours (3,103 cases; 40,941 controls) from the Ovarian Cancer Association Consortium (OCAC). The OCAC dataset comprises 63 genotyping project/case-control sets with participants of European ancestry recruited from 14 countries (US, Australia, Belarus, Germany, Belgium, Denmark, Finland, Norway, Canada, Poland, UK, Spain, Netherlands, and Sweden). SNPs were combined into multi-allelic inverse-variance-weighted fixed or random effects models to generate effect estimates and 95% confidence intervals (CIs). Three complementary sensitivity analyses were performed to examine violations of MR assumptions: MR-Egger regression and weighted median and mode estimators. A Bonferroni-corrected P value threshold was used to establish strong evidence (P < 0.0042) and suggestive evidence (0.0042 < P < 0.05) for associations. In MR analyses, there was strong or suggestive evidence that 2 of the 12 risk factors were associated with invasive epithelial ovarian cancer and 8 of the 12 were associated with 1 or more invasive epithelial ovarian cancer histotypes. There was strong evidence that genetic liability to endometriosis was associated with an increased risk of invasive epithelial ovarian cancer (odds ratio [OR] per 50% higher odds liability: 1.10, 95% CI 1.06-1.15; P = 6.94 x 10.sup.-7) and suggestive evidence that lifetime smoking exposure was associated with an increased risk of invasive epithelial ovarian cancer (OR per unit increase in smoking score: 1.36, 95% CI 1.04-1.78; P = 0.02). In analyses examining histotypes and low malignant potential tumours, the strongest associations found were between height and clear cell carcinoma (OR per SD increase: 1.36, 95% CI 1.15-1.61; P = 0.0003); age at natural menopause and endometrioid carcinoma (OR per year later onset: 1.09, 95% CI 1.02-1.16; P = 0.007); and genetic liability to polycystic ovary syndrome and endometrioid carcinoma (OR per 50% higher odds liability: 0.89, 95% CI 0.82-0.96; P = 0.002). There was little evidence for an association of genetic liability to type 2 diabetes, parity, or circulating levels of 25-hydroxyvitamin D and sex hormone binding globulin with ovarian cancer or its subtypes. The primary limitations of this analysis include the modest statistical power for analyses of risk factors in relation to some less common ovarian cancer histotypes (low grade serous, mucinous, and clear cell carcinomas), the inability to directly examine the association of some ovarian cancer risk factors that did not have robust genetic variants available to serve as proxies (e.g., oral contraceptive use, hormone replacement therapy), and the assumption of linear relationships between risk factors and ovarian cancer risk. Conclusions Our comprehensive examination of possible aetiological drivers of ovarian carcinogenesis using germline genetic variants to proxy risk factors supports a role for few of these factors in invasive epithelial ovarian cancer overall and suggests distinct aetiologies across histotypes. The identification of novel risk factors remains an important priority for the prevention of epithelial ovarian cancer., Author(s): James Yarmolinsky 1,2, Caroline L. Relton 1,2,3, Artitaya Lophatananon 4, Kenneth Muir 4, Usha Menon 5, Aleksandra Gentry-Maharaj 5, Axel Walther 6, Jie Zheng 1,2, Peter Fasching 7, Wei [...]

The role of transforming growth factor [beta] receptor type 1 (TGFBR1) polymorphisms, particularly a coding CGC insertion (rs11466445, TGFBR1*6A/9A) in exon 1, has been extensively investigated in regard to colorectal cancer (CRC) risk. These investigations have generated conflicting results. More recently, allele-specific expression (ASE) of TGFBR1 mRNA has been suggested as predisposing to CRC, with a relative risk of nearly 10-fold and a population attributable risk of ~10%. Owing to the potential importance of TGFBR1 variants in CRC, we performed a comprehensive examination of tagging SNPs at and around the gene in 3,101 CRC cases and 3,334 controls of northern European ancestry. To test whether rare or subpolymorphic TGFBR1 variants were associated with CRC risk, we sequenced the gene's exons in a subset of patients. We also evaluated TGFBR1 ASE in a panel of CRC cases and controls. Overall, we found no association between TGFBR1 polymorphisms and CRC risk. The rare variant screen did not identify any changes of potentially pathogenic effects. No evidence of greater ASE in cases than controls was detected, and no haplotype around TGFBR1 could account for the ASE reported in other studies. We conclude that neither genetic variation nor ASE at TGFBR1 is likely to be a major CRC risk factor. genetic susceptibility | transforming growth factor p receptor type 1 [sup.*] 6A/ 9A | candidate gene | low penetrance | TGF signaling doi/ 10.1073/pnas.1002816107