Cytokine gene polymorphisms in Japanese patients with hepatitis B virus infection—association between TGF-β1 polymorphisms and hepatocellular carcinoma

Background/Aims In this study, we determined the frequencies of the genotypes associated with the polymorphism of the cytokines genes, and investigated their association with the risk of hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) carriers. Methods Genetic polymorphism in the cytokines TNF-α, IFN-γ, TGF-β1, IL-6, and IL-10 were studied in 236 Japanese patients with HBV infection. The genetic polymorphisms of these cytokines were analyzed by polymerase chain reaction-sequence-specific primer (SSP). Results There was no statistically significant difference in the genetic polymorphisms of TNF-α, IFN-γ, and IL-10 genes between HBV carriers with HCC and those without HCC. However, the TGF-β1+29 (codon 10) C/C genotype was lower in HBV carriers with HCC than in those without HCC (HCC 14.6% vs non-HCC 31.9%). The association of HCC was significantly lower in HBV carriers with C/C genotype than in those with T/C or T/T genotype in position +29 of the TGF-β1 gene. Conclusions Our findings suggest that the genetic polymorphism in codon 10 of the TGF-β1 gene may play a role in HCC development in patients with chronic HBV infection.