PS-341 and histone deacetylase inhibitor synergistically induce apoptosis in head and neck squamous cell carcinoma cells

Mol Cancer Ther. 2010 Jul;9(7):1977-84. doi: 10.1158/1535-7163.MCT-10-0141. Epub 2010 Jun 22.

Abstract

Proteasome inhibitor PS-341 (also known as bortezomib) and histone deacetylase (HDAC) inhibitors have emerged as novel therapeutic agents for a variety of malignancies. In this study, we examined whether PS-341 and the HDAC inhibitor trichostatin A (TSA) induced apoptosis in head and neck squamous cell carcinoma (HNSCC), a common and lethal malignancy. We found that, although TSA treatment alone did not induce apoptosis in HNSCC cells, it significantly enhanced PS-341-induced apoptosis in HNSCC cells in vitro. Consistently, TSA significantly improved PS-341-mediated inhibition of HNSCC tumor growth in nude mice. Mechanistically, we found that TSA increased PS-341-induced Noxa expression and caspase activation in HNSCC cells. The knockdown of Noxa significantly reduced apoptosis induced by cotreatment of PS-341 and TSA. Taken together, our results provide new insight into the mechanisms of synergistic antitumor activity of the PS-341 and HDAC inhibitor regimen, offering a new therapeutic strategy for HNSCC patients.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acetylation / drug effects
  • Animals
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Apoptosis / drug effects*
  • Blotting, Northern
  • Blotting, Western
  • Boronic Acids / administration & dosage
  • Boronic Acids / pharmacology*
  • Bortezomib
  • Carcinoma, Squamous Cell / drug therapy*
  • Carcinoma, Squamous Cell / metabolism
  • Carcinoma, Squamous Cell / pathology
  • Caspases / metabolism
  • Cell Line, Tumor
  • Dose-Response Relationship, Drug
  • Drug Synergism
  • Enzyme Activation / drug effects
  • Head and Neck Neoplasms / drug therapy*
  • Head and Neck Neoplasms / metabolism
  • Head and Neck Neoplasms / pathology
  • Histone Deacetylase Inhibitors / administration & dosage
  • Histone Deacetylase Inhibitors / pharmacology
  • Histones / metabolism
  • Humans
  • Hydroxamic Acids / administration & dosage
  • Hydroxamic Acids / pharmacology*
  • Mice
  • Mice, Nude
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Pyrazines / administration & dosage
  • Pyrazines / pharmacology*
  • RNA Interference
  • Xenograft Model Antitumor Assays

Substances

  • Antineoplastic Agents
  • Boronic Acids
  • Histone Deacetylase Inhibitors
  • Histones
  • Hydroxamic Acids
  • PMAIP1 protein, human
  • Proto-Oncogene Proteins c-bcl-2
  • Pyrazines
  • trichostatin A
  • Bortezomib
  • Caspases