Increased risk of developing hepatocellular carcinoma associated with carriage of the TNF2 allele of the -308 tumor necrosis factor-α promoter gene

Background and Aims: Tumor necrosis factor-α (TNF-α) is a cytokine that may act as an endogenous tumor promoter. A genetic polymorphism of TNF-α at position -308 of the promoter region, which includes TNF1 (-308G) and TNF2 (-308A) alleles, has been found to be associated with susceptibility to various types of cancer. We conducted a study to evaluate the association between this polymorphism and hepatocellular carcinoma (HCC). Methods: We recruited 74 HCC patients and 289 healthy controls, and determined their -308 TNF-α promoter genotypes through polymerase chain reaction followed by electrophoresis. Results: Carriage of the TNF2 allele was associated with an increased risk of HCC (odds ratio [OR] = 3.5; 95% confidence interval [CI]:[2.1, 6.0]), and a trend toward a significant increase in the risk of developing HCC was observed from TNF1/TNF1, TNF1/TNF2, to TNF2/TNF2 genotypes (p < 0.01). After adjustment for gender, age, and markers of hepatitis B and C, the OR of developing HCC associated with TNF2 allele carriage was 5.3 (95% CI: [2.3, 12.1]; p < 0.01) Conclusions: Carriage of the TNF2 allele is a significant predictor of HCC independent of hepatitis B and C, and therefore it may be used as a biomarker for susceptibility to HCC.