Abstract
INTRODUCTION: Polymorphisms of the vitamin D receptor (VDR) gene have been investigated in various case-control studies to evaluate prostate cancer susceptibility; however, published data on the association between vitamin D receptor gene FokI polymorphism and prostate cancer risk are inconclusive. MATERIAL AND METHODS: To assess the impact of vitamin D receptor gene FokI polymorphism, we performed a meta-analysis of eligible studies including 9,720 patients and 9,710 control subjects. RESULTS: The overall results indicated no obvious association of this variant on prostate cancer risk. However, in subgroup analysis by ethnicity, positive associations existed in Caucasian descendents for allelic contrast (OR = 1.03, 95% CI: 1.00-1.06, p(heterogeneity) = 0.552, p = 0.026) and the dominant genetic model (OR = 1.03, 95% CI: 1.00-1.05, p(heterogeneity) = 0.856, p = 0.032). In the subgroup analysis by tumor stage, there was a significant association between this variant and advanced prostate cancer under the recessive genetic model (OR = 1.15, 95% CI: 1.01-1.32, p(heterogeneity) = 0.469, p = 0.032). In the subgroup analysis by source of control, association of the VDR FokI polymorphism and prostate cancer susceptibility was also found in population-based studies under homozygote comparison and the recessive genetic model. CONCLUSIONS: The VDR FokI polymorphism may contribute to the risk of developing prostate cancer in Caucasian and population-based studies. Further large, well-designed studies are warranted to confirm this conclusion in more detail.