Search

Cyclooxygenase-2 (COX-2) involves in multiple processes in carcinogenesis, including inflammation, apoptosis inhibition, immune response suppression, tumor cell invasion, and angiogenesis. COX-2 is overexpressed in various cancers, including gastric cancer. COX-2 is encoded by prostaglandin endoperoxide synthase 2 ( PTGS2) gene. We hypothesized that potentially functional polymorphisms in PTGS2 may contribute to gastric cancer risk. To assess this hypothesis, we conducted a case-control study with 1681 gastric cancer cases and 1916 control subjects in a Chinese population to evaluate the association between a polymorphism in 3′-untranslated region of PTGS2, rs5275, and the risk of gastric cancer. Logistic regression analysis revealed that variant allele (C) of rs5275 was significantly associated with an increased risk of gastric cancer (per allele odds ratio [OR]=1.14, 95% confidence interval [CI]=1.01-1.29, p=0.030). This association was more prominent in females (per allele OR=1.42, 95% CI=1.11-1.81, p=0.005) and nonsmokers (per allele OR=1.35, 95% CI=1.14-1.59, p=0.001). Interestingly, we detected a negative interaction between rs5275 and smoking on the gastric cancer risk ( p=0.007). Our findings indicate that PTGS2 rs5275T/C may be a candidate genetic marker for gastric cancer susceptibility. [ABSTRACT FROM AUTHOR]

A single nucleotide polymorphism (SNP) rs999737 at 14q24.1 was identified as a susceptibility marker of breast cancer in a genome-wide association study of the European population, which was also confirmed by some of the following studies in populations of European descent. However, rs999737 is very rare or nonpolymorphic in non-Europeans including Chinese, and the role of other genetic variants at 14q24.1 has not been evaluated in populations of non-European descent. In this study, we first selected 21 common tagging SNPs (minor allele frequency [MAF] >0.05 in the Chinese population) by searching the Hapmap database, covering a linage disequilibrium region of more than 70 Kb at 14q24.1, and then conducted a two-stage study (stage I: 878 cases and 900 controls; stage II: 914 cases and 967 controls) to investigate the associations between these tagging SNPs and risk of breast cancer in a Chinese population. In stage I, two SNPs (rs2842346 and rs17828907) were identified to be significantly associated with breast cancer risk ( p=0.030 and 0.027 for genotype distributions, respectively). However, no significant associations were found between these two SNPs and breast cancer risk in either stage II or the combined dataset. These findings suggest that common variants at 14q24.1 might not be associated with the risk of breast cancer in the Chinese population, which will need the replication in additional larger studies. [ABSTRACT FROM AUTHOR]