Vitamin D receptor gene polymorphism and prostate cancer risk.

Abstract

1,25-dihydroxyvitamin D, the active form of vitamin D, exerts antiproliferative effect on prostatic cells, mediated through the vitamin D receptor. In a case-control study, we examined whether the vitamin D receptor (VDR) gene polymorphism in exon 9 could affect prostate cancer susceptibility. One hundred ninety newly diagnosed prostate cancer patients and 190 age-matched men with benign prostatic hyperplasia (BPH), in whom the presence of prostate cancer was excluded clinically or histologically, were recruited for this study. The VDR TaqI polymorphism was investigated by polymerase chain reaction (PCR) following restriction fragment length polymorphism using DNA from lymphocytes. Depending on the presence or absence of the TaqI restriction site at the third position of codon 352, patients were classified as TT, Tt, or tt. The frequency of the tt genotype was not significantly different between prostate cancer patients (18%) and controls (12%; P = 0.07). The odds ratio (OR), calculated relative to individuals with the TT genotype was 1.76 (95% confidence limit (CL) = 0.90-3.45). After stratification for Gleason score and prostate specific antigen levels in a case-case comparison (n = 190), no significant associations with the VDR genotypes were detectable either. In this case-control study of Austrian Caucasians, no statistically significant association of the VDR TaqI polymorphism and prostate cancer risk was found.