De-acetylation and degradation of HSPA5 is critical for E1A metastasis suppression in breast cancer cells

Oncotarget. 2014 Nov 15;5(21):10558-70. doi: 10.18632/oncotarget.2510.

Abstract

Elevated expression of heat shock protein 5 (HSPA5) promotes drug resistance and metastasis and is a marker of poor prognosis in breast cancer patients. Adenovirus type 5 E1A gene therapy has demonstrated antitumor efficacy but the mechanisms of metastasis-inhibition are unclear. Here, we report that E1A interacts with p300 histone acetyltransferase (HAT) and blocks p300-mediated HSPA5 acetylation at K353, which in turn promotes HSPA5 ubiquitination by GP78 (E3 ubiquitin ligase) and subsequent proteasome-mediated degradation. Our findings point out the Ying-Yang regulation of two different post-translational modifications (ubiquitination and acetylation) of HSPA5 in tumor metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylation
  • Adenovirus E1A Proteins / genetics
  • Adenovirus E1A Proteins / metabolism*
  • Animals
  • Apoptosis
  • Blotting, Western
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Breast Neoplasms / prevention & control*
  • Cell Movement*
  • Cell Proliferation
  • E1A-Associated p300 Protein / genetics
  • E1A-Associated p300 Protein / metabolism*
  • Endoplasmic Reticulum Chaperone BiP
  • Female
  • Heat-Shock Proteins / genetics
  • Heat-Shock Proteins / metabolism*
  • Humans
  • Immunoenzyme Techniques
  • Immunoprecipitation
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / prevention & control*
  • Lung Neoplasms / secondary
  • Mice
  • Mice, SCID
  • Protein Binding
  • Protein Processing, Post-Translational
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tumor Cells, Cultured
  • Ubiquitination
  • Xenograft Model Antitumor Assays

Substances

  • Adenovirus E1A Proteins
  • Endoplasmic Reticulum Chaperone BiP
  • HSPA5 protein, human
  • Heat-Shock Proteins
  • Hspa5 protein, mouse
  • RNA, Messenger
  • E1A-Associated p300 Protein
  • EP300 protein, human