Polymorphisms of vitamin D receptor gene TaqI susceptibility of prostate cancer: a meta-analysis

OBJECTIVE: Many studies have investigated the association of the vitamin D receptor gene TaqI polymorphism with prostate cancer (PCa) risk. However, the evidence is inadequate to draw robust conclusions. To shed light on these inconclusive findings, we conducted a meta-analysis. MATERIALS AND METHODS: We searched PubMed for eligible articles. The relevant data were abstracted by two independent reviewers with the Stata 11.0 software. RESULTS: A total of 27 studies were included. The pooled outcomes indicated that the TaqI genetic polymorphisms were significantly associated with the risk of PCa (T vs t allele: odds ratio [OR] =1.11, 95% confidence interval [CI] =1.03–1.21, P=0.008; TT vs tt: OR =1.19, 95% CI =1.01–1.42, P=0.040; TT + Tt vs tt: OR =1.18, 95% CI =1.02–1.38, P=0.031), especially in the Asian population (T vs t allele: OR =1.11, 95% CI =1.03–1.21, P=0.008; TT/Tt vs tt: OR =1.93, 95% CI =1.02–3.66, P=0.043). In the tumor stage stratified analyses, the pooled results showed no significant difference in genetic polymorphisms between the local tumor group and the control group or between the local tumor group and the advanced tumor group. However, the genotypes TT and TT/Tt were significantly higher in the advanced PCa group compared to the control group (T vs t allele: OR =1.20, 95% CI =1.01–1.42, P=0.040; TT vs tt: OR =1.34, 95% CI =1.08–1.67, P=0.009; TT/Tt vs tt: OR =1.28, 95% CI =1.05–1.56, P=0.015). CONCLUSION: The vitamin D receptor gene TaqI allele polymorphism might be associated with a PCa risk, especially in Asians, which might provide new clues for the pathogenesis research and clinical diagnosis of PCa in the future.