IFN-γ +874 T/A polymorphisms contributes to cervical cancer susceptibility: a meta-analysis

Interferon gamma (IFN-γ) is a potent proinflammatory cytokine which plays an important role in the antiviral, antiproliferative, and antitumor activities. So our meta-analysis was conducted to evaluate the correlations between common genetic polymorphisms in the IFN-γ gene and susceptibility to cervical cancer. The +874 polymorphism in IFN gene region reportedly affects cancer risk. In order to derive a more precise estimation of the association, eight clinical case-control studies met all the inclusion criteria and were included in this meta-analysis. A total of 2,375 cancer cases and 2,106 controls were involved in this meta-analysis. Overall, no significant association was detected in allelic model (A allele vs. T allele OR=0.97, 95% CI, 0.73~1.28), homozygote comparison (AA vs. TT OR=1.12, 95% CI, 0.68~1.85), heterozygote comparison (AT vs. TT OR=1.43, 95% CI, 0.97~1.61), dominant model (AA+AT vs. TT OR=1.19, 95% CI, 0.87~1.63), nor recessive model (AA vs. AT+TT OR=0.95, 95% CI, 0.64~1.40). Subgroup analysis based on ethnicity, genotyping method, and Hardy-Weinberg equilibrium status. Ethnicity suggested that genetic polymorphisms in the IFN-γ gene were closely correlated with increased cervical cancer risk among Asians (allele model: OR=1.11, 95% CI=0.61~2.02, P<0.001; recessive model: OR=0.98, 95% CI=0.36~2.96, P<0.001; homozygous model: OR=1.43, 95% CI=0.56~3.65, P=0.001; respectively), but not among Mixed (all P>0.05). In conclusion, the current meta-analysis supported that IFN-γ genetic polymorphism may contribute to cervical cancer susceptibility, and further well-designed studies with large sample size are warranted to validate our conclusion.