Effects of four single nucleotide polymorphisms in microRNA-coding genes on lung cancer risk

No clear consensus has been reached on the four single nucleotide polymorphisms (miR-196a2 gene rs11614913, miR-146a gene rs2910164, miR-149 gene rs2292832, and miR-499 gene rs3746444) in microRNA-coding genes and lung cancer risk. We performed a meta-analysis in an effort to systematically explore the possible association. A computer retrieval of PubMed, Embase, and Institute for Scientific Information (ISI) Web of Science electronic databases was conducted prior to May 2014. References of retrieved articles were also screened. The fixed effects model and the random effects model were applied for dichotomous outcomes to combine the results of the individual studies. Seven studies including 3,705 cases and 4,099 controls were finally included according to the inclusion criteria. Statistical association could be found between rs11614913 polymorphism and lung cancer [C vs. T: P = 0.01, odds ratio (OR) = 1.11, 95% confidence interval (CI) 1.03-1.20, P heterogeneity = 0.22, fixed effects model; CC + CT vs. TT: P = 0.01, OR = 1.18, 95% CI 1.04-1.34, P heterogeneity = 0.32, fixed effects model; CC vs. TT: P = 0.009, OR = 1.24, 95% CI 1.06-1.45, P heterogeneity = 0.34, fixed effects model]. Subgroup analysis found this association in the East Asians. As for rs2910164 polymorphism and lung cancer risk, significant association could be found in allele comparison (G vs. C: P = 0.03, OR = 0.92, 95% CI 0.85-0.99, P heterogeneity = 0.15, fixed effects model) and in the dominant genetic model (GG + CG vs. CC: P = 0.03, OR = 0.86, 95 % CI 0.76-0.99, P heterogeneity = 0.31, fixed effects model). In the East Asian subgroup, association could also be found. No association was observed on rs2292832 or rs3746444 polymorphism and lung cancer. Our study suggested that the miR-196a2 gene rs11614913 polymorphism and the miR-146a gene rs2910164 polymorphism might associate with lung cancer risk.