Polymorphisms of the interleukin 6 gene and additional gene-gene interaction contribute to cervical cancer susceptibility in Eastern Chinese women.

Abstract

To investigate the association between IL-6 gene polymorphism and cervical cancer risk, and the impact of multiple gene-gene interaction on cervical cancer risk based on a Chinese Han population. A total of 1088 women were selected, including 360 cervical cancer patients and 728 control subjects. Logistic regression model was used to examine the association between SNPs within IL-6 and cervical cancer risk. Odds ratio (OR) and 95% confident interval (95% CI) were calculated. Generalized multifactor dimensionality reduction (GMDR) was employed to analyze the gene-gene interaction. Cervical cancer risks were significantly higher in carriers of C allele of rs1800795 polymorphism than those with GG genotype (GC+CC versus GG), adjusted OR (95% CI) 1.60 (1.24-2.19), and also significantly higher in carriers of G allele of rs2069837 polymorphism than those with AA (AG+GG versus AA), adjusted OR (95% CI) 1.49 (1.19-2.07). GMDR analysis found a significant gene-gene interaction between rs1800795 and rs2069837 (p=0.0010). Overall, the two-locus models had a cross-validation consistency of 10 of 10, and had the testing accuracy of 61.72%. We also calculated the odds ratios and 95% CI for this interaction, and we found that subjects with GC or CC of rs1800795 and AG or GG of rs2069837 genotype have the highest cervical cancer risk, compared to subjects with GG of rs1800795 and AA of rs2069837 genotype, OR (95% CI) 3.35 (2.01-4.78). Minor allele of rs1800795and rs2069837 and its interaction were associated with increased cervical cancer risk.