Promoter polymorphisms of miR-34b/c are associated with risk of gastric cancer in a Chinese population.

More and more evidence reveals that noncoding RNA miR-34b/c and tumor suppressor gene TP-53 independently, and/or jointly, play crucial roles in carcinogenesis. The purpose of the present hospital-based case-control study was to investigate the association between the miR-34b/c rs4938723 and TP53 Arg72Pro polymorphisms and the risk of gastric cancer. Two polymorphisms were genotyped in 419 gastric cancer patients and 402 age- and sex-matched cancer-free controls using polymerase chain reaction-restriction fragment length polymorphism analysis. The CC genotype and C allele of the miR-34b/c rs4938723 were associated with a significantly decreased risk of gastric cancer compared with the TT genotype and T allele (CC vs. TT: P = 0.006, adjusted odds ratio (OR) = 0.53, 95 % confidence interval (95 % CI) = 0.34-0.83; C vs. T: P = 0.005, adjusted OR = 0.75, 95 % CI = 0.61-0.92). Compared with individuals with the wild-type TT genotype, subjects with the variant genotypes (CT + CC) had a significantly decreased risk of gastric cancer (P = 0.047, adjusted OR = 0.75, 95 % CI = 0.57-0.99). Stratified analysis showed that the association between the risk of gastric cancer and the variant genotypes of miR-34b/c was more profound among men. However, no overall association was found between the TP53 Arg72Pro polymorphism and gastric cancer risk. In the combined analysis, no effects of the interaction of miR-34b/c rs4938723 and TP53Arg72Pro on gastric cancer risk were observed. Our findings indicate that the miR-34b/c rs4938723 CT/CC genotypes may be associated with a decreased risk of gastric cancer and the C allele may be a protective factor in gastric cancer.