Carbamazepine promotes Her-2 protein degradation in breast cancer cells by modulating HDAC6 activity and acetylation of Hsp90

Mol Cell Biochem. 2011 Feb;348(1-2):165-71. doi: 10.1007/s11010-010-0651-y. Epub 2010 Nov 17.

Abstract

Histone deacetylase 6 (HDAC6) inhibition, recently, has been shown to promote the acetylation of heat-shock protein 90 (Hsp90) and disrupt its chaperone function. Her-2 oncoprotein is identified as a client protein of Hsp90. Therefore, in this study we examined the effect of carbamazepine, which could inhibit HDAC on Hsp90 acetylation and Her-2 stability. The results of this study demonstrate that while carbamazepine had no effect on the Her-2 mRNA level, it induced Her-2 protein degradation via the proteasome pathway by disrupting the chaperone function of Hsp90 in SK-BR-3 cells. Mechanistically, carbamazepine could enhance the acetylation of α-tubulin, indicating its inhibitory effect on HDAC6. Functionally, carbamazepine could synergize with trastuzumab or geldanamycin to promote Her-2 degradation and inhibit breast cancer cell proliferation. Thus, this study has potential clinical implications by providing a promising strategy to overcome the development of resistance against trastuzumab therapy for breast cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylation
  • Antibodies, Monoclonal / pharmacology
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Combined Chemotherapy Protocols / pharmacology
  • Benzoquinones
  • Breast Neoplasms / enzymology*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / pathology
  • Carbamazepine / pharmacology*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cysteine Proteinase Inhibitors / pharmacology
  • Dose-Response Relationship, Drug
  • Drug Synergism
  • Female
  • HSP90 Heat-Shock Proteins / antagonists & inhibitors
  • HSP90 Heat-Shock Proteins / metabolism*
  • Histone Deacetylase 6
  • Histone Deacetylase Inhibitors / pharmacology*
  • Histone Deacetylases / metabolism*
  • Humans
  • Lactams, Macrocyclic
  • Leupeptins / pharmacology
  • Proteasome Endopeptidase Complex / drug effects
  • Proteasome Endopeptidase Complex / metabolism
  • Protein Processing, Post-Translational / drug effects*
  • Protein Stability
  • RNA, Messenger / metabolism
  • Receptor, ErbB-2 / genetics
  • Receptor, ErbB-2 / metabolism*
  • Time Factors
  • Trastuzumab
  • Tubulin / metabolism

Substances

  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents
  • Benzoquinones
  • Cysteine Proteinase Inhibitors
  • HSP90 Heat-Shock Proteins
  • Histone Deacetylase Inhibitors
  • Lactams, Macrocyclic
  • Leupeptins
  • RNA, Messenger
  • Tubulin
  • Carbamazepine
  • tanespimycin
  • ERBB2 protein, human
  • Receptor, ErbB-2
  • Proteasome Endopeptidase Complex
  • HDAC6 protein, human
  • Histone Deacetylase 6
  • Histone Deacetylases
  • Trastuzumab
  • benzyloxycarbonylleucyl-leucyl-leucine aldehyde