TNF-α -863 polymorphisms and the risk of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common type of highly malignant tumor. Guangxi is an area of China characterized by a high incidence of HCC. Previous epidemiological studies have found that chronic infection with hepatitis B virus (HBV) is one of the major etiological risk factors for HCC in China. With the increased understanding of the host immune response against HBV and the pathogenesis of the virus, at present, greater attention is being given to the immune response of cytokine genes, as polymorphisms may have a major impact on the course and outcome of HBV infection. In the present study, we genotyped tumor necrosis factor-α (TNF-α) rs1800629 (-308G/A), rs1800630 (-863C/A); interleukin-1B rs1143627 (-31T/C); and transforming growth factor β1 (TGF-β1) rs1800469 (-509C/T) in a hospital-based study of 772 HCC cases and 852 cancer-free controls. The distribution of the frequency of TNF-α rs1800630 sites of CC, CA, AA were 65.67, 27.46 and 6.87% in the case group, respectively, as compared with 67.02, 29.58 and 3.40% in the controls, all with a statistical significance (P<0.05). The logistic regression analysis revealed that the variant rs1800630 AA genotypes were associated with a significantly increasing risk of HCC (OR=2.058, 95% CI 1.289-3.287), compared with the wild-type rs1800630 CC. Further stratified analyses showed that after stratification for history of alcohol drinking, in a subgroup of individuals without a history of drinking, the HCC risk in the group with the TNF-α rs1800630 A allele was 1.839 times higher than that in the group with TNF-α rs1800630 C (P<0.010). These findings suggest that TNF-α rs1800630 may contribute to the risk of HCC, however, these data require further validation.