Vitamin D receptor expression in patients with vulvar cancer

The anticarcinogenic potential of vitamin D is attributed to antiproliferative and prodifferentiative effects on cells for a wide variety of carcinomas. The biological effects of 1,25(OH) ₂D (calcitriol) are mediated through a soluble receptor protein termed vitamin D receptor (VDR). However, thus far there have been no studies evaluating the association between VDR expression and vulvar cancer. Using immunohistochemical analysis, VDR expression was evaluated separately in the nucleus, cytoplasm and membrane, in vulvar cancer samples and adjacent non-pathological vulvar tissue from 48 squamous cell carcinoma patients with no prior therapy, and the association between VDR and overall survival was investigated. Overall, among the 48 vulvar cancer cases, nuclear and cytoplasmic VDR expression was present in 47 (97.9%) and 23 (47.9%) cases respectively. The median nuclear VDR expression was significantly higher as compared to the cytoplasmic VDR in the vulvar cancer tissue. No significant correlation between VDR values and the age of the patients was detected. Nuclear and cytoplasmatic VDR in the vulvar cancer tissue were also compared according to the tumor size, and no significant association between mean tumor VDR and tumor size was detected. There was no association between cytoplasmatic VDR expression and OS, but better OS was observed in patients with reduced nuclear VDR expression as compared to those with high VDR expression. VDR may be considered as a useful pathological marker.