Chromatin remodeling system p300-HDAC2-Sin3A is involved in Arginine Starvation-Induced HIF-1α Degradation at the ASS1 promoter for ASS1 Derepression

Sci Rep. 2017 Sep 7;7(1):10814. doi: 10.1038/s41598-017-11445-0.

Abstract

Argininosuccinate synthetase 1 (ASS1) is the key enzyme that controls biosynthesis of arginine (Arg). ASS1 is silenced in many human malignancies therefore, these tumors require extracellular Arg for growth. The Arg-degrading recombinant protein, pegylated arginine deiminase (ADI-PEG20), has been in clinical trials for targeting Arg auxotrophic tumors by Arg starvation therapy. Resistance to Arg starvation is often developed through reactivation of ASS1 expression. We previously demonstrated that ASS1 silencing is controlled by HIF-1α and Arg starvation-reactivated ASS1 is associated with HIF-1α downregulation. However, mechanisms underlying ASS1 repression and HIF-1α turnover are not known. Here, we demonstrate that interplay of p300-HDAC2-Sin3A in the chromatin remodeling system is involved in HIF-1α degradation at the ASS1 promoter. The histone acetyltransferase p300 is normally associated with the ASS1 promoter to maintain acetylated H3K14ac and H3K27ac for ASS1 silencing. Arg starvation induces p300 dissociation, allowing histone HDAC2 and cofactor Sin3A to deacetylate these histones at the ASS1 promoter, thereby facilitating HIF-1α-proteasomal complex, driven by PHD2, to degrade HIF-1α in situ. Arg starvation induces PHD2 and HDAC2 interaction which is sensitive to antioxidants. This is the first report describing epigenetic regulation of chromosomal HIF-1α turnover in gene activation that bears important implication in cancer therapy.

Publication types

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

MeSH terms

  • Arginine / metabolism*
  • Argininosuccinate Synthase / metabolism*
  • Cell Line
  • Chromatin Assembly and Disassembly*
  • E1A-Associated p300 Protein / metabolism*
  • Gene Expression Regulation
  • Gene Regulatory Networks
  • Histone Deacetylase 2 / metabolism*
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism*
  • Hypoxia-Inducible Factor-Proline Dioxygenases / metabolism
  • Promoter Regions, Genetic
  • Proteolysis
  • Repressor Proteins / metabolism*
  • Sin3 Histone Deacetylase and Corepressor Complex

Substances

  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Repressor Proteins
  • SIN3A transcription factor
  • Arginine
  • EGLN1 protein, human
  • Hypoxia-Inducible Factor-Proline Dioxygenases
  • E1A-Associated p300 Protein
  • EP300 protein, human
  • HDAC2 protein, human
  • Histone Deacetylase 2
  • Sin3 Histone Deacetylase and Corepressor Complex
  • Argininosuccinate Synthase