Association of Single Nucleotide Polymorphisms in Tumor Necrosis Factor-Alpha with Cervical Cancer Susceptibility

Tumor necrosis factor-alpha (TNF-alpha) polymorphisms have been reported to play an important role in the development of cervical cancer. But the results remain inconclusive. We performed this study to provide a comprehensive assessment of the association by means of a meta-analysis in which all published studies were included. The studies investigating the associations between cervical cancer risk and TNF-alpha polymorphisms were identified through PubMed, Embase, CNKI, and Chinese BioMedical Literature Database. OR and 95 % CI (odds ratio and 95 % confidence interval) were calculated using either the fixed or random effects model to assess the associations. We eventually included eighteen case-control studies of SNP -308 G > A and nine studies of SNP -238 G > A. Meta-analysis of the former polymorphism suggested significantly increased risk of cervical cancer associated with the A allele (OR 1.19, 95 % CI 1.02-1.38). Subgroup analysis according to ethnicity showed similar results in Caucasians (A vs. G: OR 1.25, 95 % CI 1.02-1.54; AA vs. GG: OR 1.47, 95 % CI 1.04-2.08; AA vs. GA+GG: OR 1.47, 95 % CI 1.04-2.08). For SNP -238 G > A, a protective association was observed in overall comparisons (A vs. G: OR 0.64, 95 % CI 0.51-0.80; AA+GA vs. GG: OR 0.62, 95 % CI 0.49-0.79) and subgroup analysis of Caucasians (A vs. G: OR 0.67, 95 % CI 0.53-0.83; AA+GA vs. GG: OR 0.65, 95 % CI 0.51-0.82). Our meta-analysis indicates that TNF-alpha polymorphisms may confer susceptibility to cervical cancer in an ethic-specific fashion.