MiR-146a rs2910164 polymorphism increases risk of gastric cancer: a meta-analysis.

Abstract

To systematically evaluate the association between the miR-146a rs2910164 polymorphism and susceptibility to gastric cancer. A comprehensive electronic search was conducted for articles published up until January 27, 2014 in Medline (PubMed), Excerpta Medica Database (Embase), the Cochrane Library and Google Scholar. Only case-control studies published in English that evaluated the association between the miR-146a rs2910164 polymorphism and susceptibility to gastric cancer were included. Furthermore, only studies with sufficient data allowing for calculation of odds ratio (OR) and corresponding 95% confidence interval (CI) were included. These values were used in the quantitative synthesis to assess the strength of the association between the miR-146a rs2910164 polymorphism and risk of gastric cancer. The database search identified 1002 eligible studies, of which seven (comprising 4112 cases and 5811 controls) were included for the meta-analysis. The results indicate that miR-146a rs2910164 polymorphism is more likely to be associated with gastric cancer risk. In the overall analysis, a significantly increased cancer risk was found in the heterozygote (GG vs GC) comparison (OR = 1.14, 95%CI: 1.03-1.27; P = 0.01 for pooled OR). In the ethnicity subgroup analysis, a similar result was found among Caucasians (OR = 1.36, 95%CI: 1.01-1.85; P = 0.04 for pooled OR). In the stratified analysis by quality of studies, a significantly increased cancer risk was found in the heterozygote comparison among high quality studies (OR = 1.12, 95%CI: 1.01-1.26; P = 0.04 for pooled OR). When stratified on the basis of sample size, a significantly increased cancer risk was found among small sample size subgroups for the allelic (G vs C: OR = 1.16, 95%CI: 1.03-1.30; P = 0.01), homozygote (GG vs CC: OR = 1.33, 95%CI: 1.03-1.73; P = 0.03) and recessive model (GG vs GC + CC: OR = 0.05, 95%CI: 0.00-0.10; P = 0.03) comparisons. The miR-146a rs2910164 polymorphism is associated with increased gastric cancer risk, particularly evident in high quality studies with small sample sized Caucasian populations.