Vitamin D Receptor <i>Fok I</i> Polymorphism and Risk of Hepatocellular Carcinoma in HBV-Infected Patients

Abstract

Context: We conducted a meta-analysis to evaluate the role of the vitamin D receptor (VDR) polymorphism in the risk of hepatocellular carcinoma (HCC) in patients infected with hepatitis B virus (HBV). Objective: To develop new preventions, mechanisms, and therapies for HCC, it is important to investigate the underlying causes of HCC. Recently, there has been increasing attention to the relationship between VDR polymorphism and the risk of HBV-related HCC, but no specific conclusion has been made. Data Sources: PubMed/Medline, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals, Wanfang Data, and SINOMED databases were searched until August 2018. Studies reporting VDR polymorphism and HBV-related HCC risks were included and the quality was assessed by Newcastle-Ottawa scale (NOS). Odds ratio (OR) and 95% confidence interval (CI) were calculated to compare the pooled data between HCC risks and different genotypes, such as FF, Ff, F, f, and ff, with each other. Results: Three case-control studies with totally 728 HBV-related HCC cases and 920 HBV controls were included. When comparing HBV-related HCC cases with HBV controls, our data showed that all genotypes of Fok I polymorphism significantly increased the risk of HCC in the overall population (ff vs. FF: OR = 1.816, 95% CI = 1.161 - 2.841, P = 0.0009; Ff vs. FF: OR = 1.315, 95% CI = 1.037 - 1.667, P = 0.024; ff/Ff vs. FF, OR = 1.504, 95% CI = 1.206 - 1.876, P < 0.001; ff vs. FF/Ff: OR = 1.591, 95% CI = 1.270 - 1.992, P < 0.001; ff vs. Ff: OR = 1.435, 95% CI = 1.127 - 1.827, P = 0.003; f vs. F: OR = 1.375, 95% CI = 1.075 - 1.759). Conclusion: The results of our analysis suggest the “f” allele of Fok I polymorphism might be a risk factor for HCC in HBV-infected patients and it could be a predictive factor to screen HCC in HBV-infected patients. However, more accurate analyses and larger studies are needed.