No evidence for amplification of 25-hydroxyvitamin D-1alpha-OHase (1alpha-OHase) or 1,25-dihydroxyvitamin D-24-OHase (24-OHase) genes in malignant melanoma (MM).

Increasing evidence points at an important function of Vitamin D metabolites for growth regulation in various tissues, including MM. Using array CGH, amplification of 24-OHase was recently detected as a likely target oncogene of the amplification unit 20q13.2 in breast cancer cell lines and tumors. Additionally, amplification of 1alpha-OHase has been reported in human malignant glioma. Using immunohistochemistry, we have now detected nuclear Vitamin D receptor (VDR) immunoreactivity in primary cutaneous malignant melanoma (MM), indicating that Vitamin D metabolites may be of importance for the growth regulation in these tumors. Using Southern analysis, we have analyzed MM and metastases for evidence of amplification of 1alpha-OHase or 24-OHase genes. Our results do not support the hypothesis that amplification of 1alpha-OHase or 24-OHase genes may be of importance for pathogenesis or progression of MM.