Genetic Polymorphisms in miR-146a, miR-196a2 and miR-125a Genes and its Association in Prostate Cancer.

The increase in incidence of prostate cancer in the Indian Population stresses the need to identify genetic markers for susceptibility and prognosis. Recent studies show that microRNAs play an important role in tumorigenesis by altering proliferation, differentiation and cell death. Gene polymorphisms not only in promoter region but also within miRNA gene have been shown to affect expression. The present study was aimed to analyze the role of miR-146a, miR-196a2 and miR-125a gene polymorphisms in prostate cancer. Genotyping of three SNPs rs73318382, rs57095329, rs2910164 in miRNA146a, rs11614913 in miR-196a2 and rs41275794, rs12976445, rs10404453 and rs1297533 in miR-125a was performed in 100 cases and 100 controls. Statistical analysis revealed the heterozygous AG genotype of the rs57095329 was significantly decreased in the cases when compared to the controls (OR-0.45, CI -0.24 to 0.85, p value-0.02) indicating an inverse association of this genotype with prostate cancer. Further the heterozygous CT of miR-196a2 (rs11614913) (OR-1.88, CI-1.06 to 3.35, p-0.02) and homozygous CC of miR-125a (rs12976445) (OR-2.55, CI -1.15 to 4.65, p-0.03) showed increased risk for prostate cancer. Combined analysis of all the genotypes revealed that the haplotype combination AGGCGTGG (OR = 0.09 at CI 95% (0.01-0.65) showed an inverse association with prostate cancer. Stratified analysis based on the age and tumor grade revealed no significant association.