OBJECTIVES: To evaluate the relationship between the five common polymorphisms in miRNAs (miR-146a rs2910164 G>C, miR-149 rs2292832 C>T, miR-196a2 rs11614913 C>T, miR-499 rs3746444 A>G and miR-27a rs895819 A>G), and breast cancer (BC) risk.METHODS: Meta-analyses were performed on 15 published studies involving 8, 361 BC patients and 8, 504 cancer-free controls. There were 8 studies with 4, 314 cases and 4, 485 controls for rs2910164, 3 studies with 1, 439 cases and 1, 508 controls for rs2292832, 10 studies with 4, 618 cases and 5, 590 controls for rs11614913, 5 studies with 2, 924 cases and 3, 563 controls for rs3746444, and 5 studies with 2, 912 cases and 3, 697 controls for rs895819. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the BC risk.RESULTS: Meta-analyses showed that rs2910164 (miR-146a) was associated with BC risk in Caucasian population (homozygote comparison: OR = 1.29, 95%CI = 1.02-1.63, P=0.03; dominant model: OR = 1.31, 95% CI = 1.05-1.65, P=0.02), whereas negative results were obtained for Asians in all genetic models. rs11614913 (miR-196a2) was associated with BC risk in the overall population based on the recessive model (OR = 0.89, 95% CI = 0.80-0.99, P=0.03). Association of rs3746444 (miR-499) with BC risk was detected under three genetic models (allele contrast genetic model: OR = 1.13, 95%CI = 1.03-1.23, P=0.007; homozygote comparison: OR = 1.36, 95 %CI = 1.10-1.69, P=0.005 and recessive model: OR = 1.38, 95% CI = 1.12-1.70, P=0.003). When stratified by ethnicity, the effects remained in Asians. rs895819 (miR-27a) was associated with BC risk in the overall population based on the allele contrast genetic model (OR = 0.91, 95%CI = 0.85-0.98, P=0.02); heterozygote comparison (OR = 0.89, 95 %CI = 0.80-0.99, P=0.03) and the dominant model (OR = 0.89, 95% CI = 0.80-0.98, P=0.02). However, there was no association between rs2292832 (miR-149) polymorphism and BC susceptibility.CONCLUSION: Our meta-analysis results suggested that the rs2910164 and rs3746444 polymorphisms are associated with increased BC risk, while the rs11614913 and rs895819 polymorphisms correlate with reduced BC risk.
Asian Continental Ancestry Group Breast Neoplasms