Silencing and re-expression of retinoic acid receptor beta2 in human melanoma

Pigment Cell Melanoma Res. 2010 Jun;23(3):419-29. doi: 10.1111/j.1755-148X.2010.00702.x. Epub 2010 Mar 29.

Abstract

Many melanoma cells are resistant to the anti-proliferative effect of all trans retinoic acid (ATRA). Retinoic Acid Receptor-beta2 (RAR-beta2) mediates the ATRA growth inhibition. We found a correlation between the anti-proliferative activity of ATRA and expression of RAR-beta2. There was not a strict correlation between DNA methylation of RAR-beta gene and its expression. There was no difference in global and RARbeta specific nucleosome repeat length (NRL) in melanoma and melanocytes or between control and ATRA treated cells. Pan-acetylation of H3 and H4 within the RAR-beta gene promoter was higher in cells expressing RAR-beta2. All trans retinoic acid treatment of responsive cells did not change pan-acetylation of H3/H4, but addition of ATRA to non-responsive cells increased H4 pan-acetylation. Phytochemicals or the histone deacetylase inhibitor Trichostatin A did not restore expression of RAR-beta2. Treatment of WM1366 melanoma cells with 5-aza 2'-deoxycytidine reactivated RAR-beta2 gene expression and restored the ability of ATRA to further induce the expression of this gene. Therefore, promoter methylation is responsible for silencing of RAR-beta2 in some melanoma cells and pan-acetylation of H3 likely plays a permissive role in expression of RAR-beta2.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acetylation / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Chromatin Immunoprecipitation
  • DNA Methylation / drug effects
  • Disease Progression
  • Gene Expression Regulation, Neoplastic* / drug effects
  • Gene Silencing* / drug effects
  • Histones / metabolism
  • Humans
  • Melanocytes / drug effects
  • Melanocytes / metabolism
  • Melanocytes / pathology
  • Melanoma / genetics*
  • Melanoma / pathology
  • Nucleosomes / metabolism
  • Promoter Regions, Genetic
  • Protein Processing, Post-Translational / drug effects
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors, Retinoic Acid / genetics*
  • Receptors, Retinoic Acid / metabolism
  • Skin Neoplasms / genetics*
  • Skin Neoplasms / pathology
  • Tretinoin / pharmacology

Substances

  • Histones
  • Nucleosomes
  • RNA, Messenger
  • Receptors, Retinoic Acid
  • retinoic acid receptor, beta2, human
  • Tretinoin