Vitamin A metabolism and mRNA expression of retinoid-binding protein and receptor genes in human epidermal melanocytes and melanoma cells

Melanoma Res. 1997 Aug;7(4):267-74. doi: 10.1097/00008390-199708000-00001.

Abstract

Retinoids inhibit proliferation of melanocytes and melanoma cells and affect disorders of hypo- and hyperpigmentation. Such effects might involve retinoid-binding proteins, retinoid metabolites and nuclear retinoid receptors for transcriptional activation. We detected messenger RNA transcripts for the cellular retinol- and retinoic acid-binding proteins (CRBP, CRABP I and II) in cultured epidermal melanocytes. In the melanoma cell lines the major transcript was CRABP II. Nuclear retinoic acid (RA) receptor transcripts and the 9-cis-retinoic acid receptor transcript were detected in all cells. The endogenous concentrations of retinol (ROH) and its metabolite 3,4-didehydroretinol (ddROH) in melanocytes were five times those in melanoma cells. When cells were incubated with [3H]ROH the main metabolites in the melanocytes were [3H]ddROH (4%) and [3H]RA (0.4%). Formation of [3H]RA was only detected in one melanoma cell line. Both melanocytes and melanoma cells produced an unidentified metabolite when incubated with [3H]ROH and [3H]RA. Dissimilarities in the metabolism and endogenous concentration of retinoids between benign and malignant melanocytes might play a key role in differentiation and growth regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cells, Cultured
  • Child
  • Gene Expression
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Melanocytes / metabolism*
  • Melanoma / metabolism*
  • Polymerase Chain Reaction
  • RNA, Messenger / metabolism*
  • Receptors, Cell Surface / biosynthesis*
  • Receptors, Cell Surface / genetics
  • Retinol-Binding Proteins / biosynthesis*
  • Retinol-Binding Proteins / genetics
  • Retinol-Binding Proteins, Cellular
  • Skin / cytology
  • Skin / metabolism*
  • Tretinoin / metabolism
  • Tritium
  • Tumor Cells, Cultured
  • Vitamin A / metabolism*

Substances

  • RNA, Messenger
  • Receptors, Cell Surface
  • Retinol-Binding Proteins
  • Retinol-Binding Proteins, Cellular
  • retinol binding protein receptor
  • Tritium
  • Vitamin A
  • Tretinoin