Interferon-γ +874A/T Polymorphism and Hepatocellular Carcinoma Risk: A Meta-Analysis

BACKGROUND Studies have evaluated the association between interferon-γ (IFN-γ) +874A/T polymorphism and hepatocellular carcinoma (HCC) risk, but the results are controversial. We performed this meta-analysis to further investigate this association. MATERIAL AND METHODS Relevant studies were searched by using the PubMed, Web of Science, and Embase databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. Subgroup analysis and sensitivity analysis were conducted. RESULTS Seven case-control studies (859 HCC patients and 1482 healthy controls) were identified to assess the association between IFN-γ +874A/T polymorphism and risk of HCC. IFN-γ +874A/T polymorphism was significantly associated with an increased risk of HCC (OR=1.38; 95% CI 1.12-1.70; P=0.002). In the subgroup analysis by ethnicity, IFN-γ +874A/T polymorphism was significantly associated with HCC risk in Asians (OR=1.42; 95% CI 1.08-1.87; P=0.01), but no significant association was found in Caucasians (OR=1.21; 95% CI 0.86-1.70; P=0.28). IFN-γ +874A/T polymorphism also increased HBV-induced HCC risk (OR=1.42; 95% CI 1.08-1.87; P=0.01). In the subgroup analysis by control source, IFN-γ +874A/T polymorphism was associated with HCC risk in hospital-based studies (OR=1.45; 95% CI 1.09-1.53; P=0.01). A marginal association was found in population-based studies (OR=1.33; 95% CI 0.97-1.83; P=0.08). CONCLUSIONS This meta-analysis indicates that the IFN-γ +874A/T polymorphism might contribute to HCC risk.