Estrogen receptor α inhibitor activates the unfolded protein response, blocks protein synthesis, and induces tumor regression

Abstract

Late-stage estrogen receptor α (ERα)-positive breast and ovarian cancers exhibit many regulatory alterations and therefore resist therapy. Our novel ERα inhibitor, BHPI, stops growth and often kills drug-resistant ERα + cancer cells and induces rapid and substantial tumor regression in a mouse model of human breast cancer. BHPI distorts a normally protective estrogen–ERα-mediated activation of the unfolded protein response (UPR) and elicits sustained UPR activation. The UPR cannot be deactivated because BHPI, acting at a second site, inhibits production of proteins that normally help turn it off. This persistent activation converts the UPR from protective to lethal. Targeting therapy-resistant ERα-positive cancer cells by converting the UPR from cytoprotective to cytotoxic may hold significant therapeutic promise.

Document Details

Document Type
Pub Defense Publication
Publication Date
Mar 30, 2015
Source ID
10.1073/pnas.1403685112

Entities

People

  • Chengjian Mao
  • David J. Shapiro
  • Lily Mahapatra
  • Mathew M. Cherian
  • Neal D. Andruska
  • William G Helferich
  • Xiaobin Zheng
  • Xujuan Yang

Organizations

  • National Cancer Institute
  • National Institute of Diabetes and Digestive and Kidney Diseases
  • Office of Dietary Supplements
  • United States Department of Defense
  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Biology

Readers

  • Cellular and Molecular Pathways of Apoptosis.
  • Oncology (Cancer Research).