Regulation of AML2/CBFA3 in hematopoietic cells through the retinoic acid receptor alpha-dependent signaling pathway

J Biol Chem. 1999 Jul 30;274(31):21651-8. doi: 10.1074/jbc.274.31.21651.

Abstract

AML2 is a member of the acute myelogenous leukemia, AML family of transcription factors. The biologic functions of AML1 and AML3 have been well characterized; however, the functional role of AML2 remains unknown. In this study, we found that AML2 protein expressed predominantly in cells of hematopoietic origin is a nuclear serine phosphoprotein associated with the nuclear matrix, and its expression is not cell cycle-related. In HL-60 cells AML2 expression can be induced by all three natural retinoids, all-trans-retinoic acid (RA), 13-cis-RA, and 9-cis-RA in a dose-dependent manner. A synthetic retinoic acid derivative, 4HPR, which neither activates RA receptor (RAR) alpha nor retinoic X receptor alpha was unable to induce the expression of AML2. A RAR-selective activator, TTNPB, induced AML2 expression similar to RA. Our study further showed that AGN193109, a potent RARalpha antagonist, suppressed AML2 expression induced by RA and that a retinoic X receptor pan agonist AGN194204 had no effect on its expression. Taken together, these studies conclusively demonstrated that the expression of AML2 in HL-60 cells is regulated through the RARalpha-specific signaling pathway. Our study further showed that after all-trans-retinoic acid priming, AML2 expression could be augmented by vitamin D(3). Based on these studies we hypothesize that AML2 expression is normally regulated by retinoid/vitamin D nuclear receptors mainly through the RARalpha-dependent signaling pathway and that it may play a role in hematopoietic cell differentiation.

Publication types

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

MeSH terms

  • Alitretinoin
  • Animals
  • Cell Line
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Dose-Response Relationship, Drug
  • Female
  • Gene Expression Regulation* / drug effects
  • HL-60 Cells
  • Hematopoietic Stem Cells / drug effects
  • Hematopoietic Stem Cells / metabolism*
  • Humans
  • Isotretinoin / pharmacology
  • Male
  • Neoplasm Proteins*
  • Receptors, Retinoic Acid / antagonists & inhibitors
  • Receptors, Retinoic Acid / physiology*
  • Retinoic Acid Receptor alpha
  • Retinoids / pharmacology*
  • Signal Transduction*
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Tretinoin / pharmacology
  • Tumor Cells, Cultured

Substances

  • DNA-Binding Proteins
  • Neoplasm Proteins
  • RARA protein, human
  • Receptors, Retinoic Acid
  • Retinoic Acid Receptor alpha
  • Retinoids
  • Transcription Factors
  • Alitretinoin
  • Tretinoin
  • Isotretinoin