Androgen receptors in human melanoma cell lines IIB-MEL-LES and IIB-MEL-IAN and in human melanoma metastases

Abstract

The presence and characteristics of androgen receptors (AR) have been des­cribed by our group in one human melanoma cell line. We now investigated their presence in two other human melanoma cell lines, IIB-MEL-LES and IIB-MEL-IAN, as well as in biopsies of human metastatic melanoma. Scatchard analysis revealed a single binding component for both cell lines, the apparent dissociation constant obtained being 15 nM, with a binding capacity of 280 fmol/mg total cell protein for IIB-MEL-LES cells and of 14 nM with a binding capacity of 206 fmol/mg total cell protein for IIB-MEL-IAN. When specifi­ci­ty was assessed, as seen before, not only androgen and anti­an­dro­gen, but also non-andro­ge­nic com­pounds were able to compete for [3H]-R1881 binding. When immu­nocyto­che­mis­try of IIB-MEL-LES and IIB-MEL-IAN cells was performed for AR, both cell lines were deeply stained in the nu­cleus whe­reas no staining was found for oestrogen and pro­ges­te­rone receptors. Every specimen of mela­no­ma metas­ta­ses tested for the presence of AR was deeply stained, and the intensity of the stai­ning was high in the majority. Several hormones and antihormones were tested for their ability to affect cell proli­fe­ration. On both cell lines, Testosterone, Dihydrotesterone, Oestradiol and Pro­ges­terone significantly stimulated cell proliferation, with reversion by Hydroxy-Flutamide, Casodex or Tamo­xi­fen.