ObjectiveMany 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 methodsWe searched PubMed for eligible articles. The relevant data were abstracted by two independent reviewers with the Stata 11.0 software.ResultsA 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).ConclusionThe 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.

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The relationship between XRCC1 polymorphisms and bladder cancer has been widely studied. Here, our meta-analysis was conducted to evaluate the correlations between common genetic polymorphisms in XRCC1 and susceptibility to bladder cancer. In order to derive a more precise estimation of the association, 27 clinical case-control studies (which met all the inclusion criteria) were included in this meta-analysis. A total of 8,539 cancer cases and 10,750 controls were involved in this meta-analysis. Overall, no significant association was detected in allelic model (A allele vs T allele odds ratio [OR] =0.87, 95% confidence interval [CI], 0.71–1.06), homozygote comparison (AA vs GG OR =1.12, 95% CI, 0.68–1.85), heterozygote comparison (AT vs TT OR =1.01, 95% CI, 0.81–1.26), dominant model (AA + AG vs GG OR =0.93, 95% CI, 0.85–1.02), and recessive model (AA vs AG + GG OR =1.01, 95% CI, 0.88–1.15), but a moderately significant association was found for AG vs GG (OR =0.241, 95% CI =0.17–0.35). Subgroup analysis based on ethnicity. Ethnicity analysis suggested that genetic polymorphisms in XRCC1 were not correlated with increased bladder cancer risk among Asians (all P>0.05). Therefore, we concluded that XRCC1 genetic polymorphism may not contribute to bladder cancer susceptibility in the present meta-analysis, and further well-designed studies with a large sample size are warranted to validate our conclusion.