Association between polymorphisms of the androgen and vitamin D receptor genes with prostate cancer risk in a Mexican population.

INTRODUCTION

Prostate cancer (PCa) is a worldwide health issue, because of its high incidence and mortality. Its etiology is complex and includes certain risk factors such as age, hormonal status, ethnic origin and family history of PCa. Genetic predisposition is proposed as a major risk factor and there are several controversial reports on the association of PCa and gene polymorphism such as the receptors of the androgen receptor (AR) and the vitamin D (VDR). Objective. To evaluate the CAG triplet repeats in the first exon of the AR and polymorphisms in the restriction site Taql in the VDR in Mexicans with PCa.

MATERIAL AND METHODS

A total of 68 Mexicans with histopathological diagnosis of PCa and 48 healthy Mexican with normal prostate-specific antigen and rectal exam where included. 10ml of peripheral blood were extracted to isolate DNA and the polymorphisms were evaluated with specific primers for the AR and VDR.

RESULTS

The allelic and genetic distributions of the AR and VDR polymorphisms were consistent with the Hardy-Weinberg equilibrium, and there were no statistical differences between the PCa patients and controls (p > 0.05). However, there was a statistical difference between the number of CAG repeats in younger patients with PCa compared to controls (p = 0.045) but when the young patient group was compared versus the elder group there was not stadistically difference (p = 0.085), but the results showed a tendency towards less repetitions of CAG in elder patients. Concerning the VDR, when we analyzed the patients with PCa and a bad pathological prognosis they had a less frequent genotype of TT (p = 0.03).

CONCLUSIONS

Our results suggest an association between the VDR and AR gene polymorphisms, and the histopathological score and age at diagnosis in Mexican patients with PCa, respectively. However, it is important to confirm these results in a larger scale study.