The miR-149 rs2292832 T/C polymorphism may decrease digestive cancer susceptibility: an updated meta-analysis.

MicroRNAs (miRNAs) are a class of short non-coding, single stranded RNAs, which perform post-transcriptional regulatory functions as tumor suppressors or oncogenes. Single nucleotide polymorphisms (SNPs) in miRs genes are currently being identified for contributing to cancer risk, prognosis and survival, however, an association between miR-149 rs2292832 T/C SNP and cancer risk is uncertain. Therefore, we performed an updated meta-analysis of all currently publications to clarify this relationship. From PubMed and Chinese language (WanFang) databases, we located articles published up to June 1, 2015, obtaining 21 case-control studies from 20 different articles containing 8913 cases and 9944 controls based on search criteria for cancer susceptibility related to the miR-149 rs2292832 T/C SNP. Odds ratios (OR) and 95% confidence intervals (CI) revealed association strengths. There had no association between this SNP and whole cancer risk. At the same time, in several subgroups, also no association was found in ethnicity, sex and smoking status. Nevertheless, poorly significant association was detected in cancer type (Digestive cancer: OR = 0.90, 95% CI = 0.81-1.00, Pheterogeneity = 0.142 for CT vs. TT) and source of control (population-based: OR = 1.15, 95% CI = 1.00-1.32, Pheterogeneity = 0.427 for CC vs. CT+TT) subgroups. The miR-149 rs2292832 T/C SNP may poorly decrease digestive cancer risk. Studies with larger samples and gene-environment interactions are warranted to understand the role of miR-149 polymorphisms, especially rs2292832 T/C SNP, in whole cancer risk.