Polymorphism of the pre-miR-146a is associated with risk of cervical cancer in a Chinese population.

Objective: MicroRNAs are tiny non-coding RNAs that reportedly play an important role in numerous physiological processes. A G>C polymorphism (rs2910164) is located on the passenger strand of the precursor of miR-146a, which could alter mature miR-146a expression. We hypothesized that a possible association exists between miR-146a gene polymorphisms and cervical cancer risk in a population-based control study of female residents in Jiangsu Province.

Methods: The subjects included 447 cervical cancer cases and 443 cancer-free controls with frequency matched by age. We genotyped the functional polymorphism of miR-146a (rs2910164) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, and used a sample of 24 cervical cancer tissue to test the expression of miR-146a by real-time quantitative reverse transcription.

Results: Our study indicated that the subjects carrying GG homozygote had a 1.496-fold increased risk than those carrying CG/CC genotypes (95% CI=1.068-2.095). Moreover, miR-146a quantification showed that the carriers of GG genotype had obviously more reduced miR-146a expression level compared with the carriers of CC genotype.

Conclusion: Our study suggests that the risk of cervical cancer in a Chinese population partly results from miRNA-146a expression deviation in vivo, being caused by common polymorphism in miR-146a. This is an initial study to indicate that miR-146a (rs2910164) might contribute to cervical cancer susceptibility.