Immunohistochemical evaluation of vitamin D receptor (VDR) expression in cutaneous melanoma tissues and four VDR gene polymorphisms

Objective: Vitamin D receptor (VDR) mediates vitamin D activity. We examined whether VDR expression in excised melanomatissues is associated with VDR gene (VDR) polymorphisms. Methods: We evaluated VDR protein expression (by monoclonal antibody immunostaining), melanoma characteristics, andcarriage of VDR-FokI-rs2228570 (C>T), VDR-BsmI-rs1544410 (G>A), VDR-ApaI-rs7975232 (T>G), and VDR-TaqI-rs731236(T>C) polymorphisms (by restriction fragment length polymorphism). Absence or presence of restriction site was denoted by acapital or lower letter, respectively: “F” and “f” for FokI, “B” and “b” for BsmI, “A” and “a” for ApaI, and “T” and “t” for TaqIendonuclease. Seventy-four Italian cutaneous primary melanomas (52.1±12.7 years old) were studied; 51.4% were stage I, 21.6%stage II, 13.5% stage III, and 13.5% stage IV melanomas. VDR expression was categorized as follows: 100% positive vs. 1, regression, tumor-infiltrating lymphocytes, tumoral infiltration of vascular tissues, additional skin andnon-skin cancers, and melanoma familiarity. Conclusions: We highlighted that VDR polymorphisms can affect VDR expression in excised melanoma cells. Low VDRexpression in AATT carriers is a new finding that merits further study. VDR expression possibly poses implications for vitamin Dsupplementation against melanoma. VDR expression and VDR genotype may become precise medicinal tools for melanoma in thefuture.