The histone deacetylase inhibitor, Vorinostat, represses hypoxia inducible factor 1 alpha expression through translational inhibition

PLoS One. 2014 Aug 28;9(8):e106224. doi: 10.1371/journal.pone.0106224. eCollection 2014.

Abstract

Hypoxia inducible factor 1α (HIF-1α) is a master regulator of tumor angiogenesis being one of the major targets for cancer therapy. Previous studies have shown that Histone Deacetylase Inhibitors (HDACi) block tumor angiogenesis through the inhibition of HIF-1α expression. As such, Vorinostat (Suberoylanilide Hydroxamic Acid/SAHA) and Romidepsin, two HDACis, were recently approved by the Food and Drug Administration (FDA) for the treatment of cutaneous T cell lymphoma. Although HDACis have been shown to affect HIF-1α expression by modulating its interactions with the Hsp70/Hsp90 chaperone axis or its acetylation status, the molecular mechanisms by which HDACis inhibit HIF-1α expression need to be further characterized. Here, we report that the FDA-approved HDACi Vorinostat/SAHA inhibits HIF-1α expression in liver cancer-derived cell lines, by a new mechanism independent of p53, prolyl-hydroxylases, autophagy and proteasome degradation. We found that SAHA or silencing of HDAC9 mechanism of action is due to inhibition of HIF-1α translation, which in turn, is mediated by the eukaryotic translation initiation factor--eIF3G. We also highlighted that HIF-1α translation is dramatically inhibited when SAHA is combined with eIF3H silencing. Taken together, we show that HDAC activity regulates HIF-1α translation, with HDACis such as SAHA representing a potential novel approach for the treatment of hepatocellular carcinoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Eukaryotic Initiation Factor-3 / metabolism
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Silencing
  • Histone Deacetylase Inhibitors / pharmacology*
  • Histone Deacetylases
  • Humans
  • Hydroxamic Acids / pharmacology*
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics*
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Liver Neoplasms / metabolism*
  • Protein Biosynthesis / drug effects*
  • Repressor Proteins / antagonists & inhibitors
  • Vorinostat

Substances

  • Eukaryotic Initiation Factor-3
  • HIF1A protein, human
  • Histone Deacetylase Inhibitors
  • Hydroxamic Acids
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Repressor Proteins
  • Vorinostat
  • HDAC9 protein, human
  • Histone Deacetylases

Grants and funding

MB was supported by a fellowship from the Foundation pour la Recherche Médicale (FRM), SPF20130526734. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.