Vitamin D receptor Taq I polymorphism and the risk of prostate cancer: a meta-analysis

// Shaosan Kang 1, * , Yansheng Zhao 2, * , Lei Wang 1 , Jian Liu 1 , Xi Chen 1 , Xiaofeng Liu 3 , Zhijie Shi 4 , Weixing Gao 1 and Fenghong Cao 1 1 Department of Urology, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, China 2 Department of Imaging, KaiLuan General Hospital, Tangshan 063000, China 3 Department of Surgery, LaoTing Traditional Chinese Medicine Hospital, Tangshan 063600, China 4 Department of Urology, TangShan Gongren Hospital, Tangshan 063000, China * These authors contributed equally to this work Correspondence to: Shaosan Kang, email: kangshaosan@163.com Keywords: Taq I; prostate cancer; vitamin D receptor; polymorphisms; meta-analysis Received: September 11, 2017      Accepted: December 15, 2017      Published: December 22, 2017 ABSTRACT Numerous previous studies reported the association of Vitamin D receptor gene Taq I polymorphism with prostate cancer risk, however these results were controversial. In order to provide a relatively comprehensive description of this relationship, we conducted this meta-analysis by searching PubMed, Embase, and China National Knowledge Infrastructure. Finally, 36 studies with 8,423 cases and 8,887 controls were included. Taq I polymorphism was found to marginally increase the prostate cancer risk in recessive genetic model (tt/Tt vs. TT: Odds Ratio (OR) = 0.89, 95% Confidence Interval (CI) = 0.80–1.00, p = 0.05) and allele genetic model (t vs. T allele: OR = 0.91, 95% CI = 0.84–0.99, p = 0.003) in the overall analysis. Subgroup analyses showed that significant increased risk was found in Asians in homozygote model (tt vs. TT: OR = 0.63, 95% CI = 0.41–0.95, p = 0.029) and allele genetic model (t vs. T: OR = 0.78, 95% CI = 0.67–0.90, p = 0.002), and in the subgroup of population-based controls in all the genetic models. These results suggest that Taq I polymorphism might be a risk factor of prostate cancer risk, especially in Asians. It could be considered as a promising target to predict the prostate cancer risk for clinical practice.