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Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer
10:36

Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer

Published on: March 17, 2016

Circumventing tamoxifen resistance in breast cancers using antiestrogens that induce unique conformational changes in

C E Connor1, J D Norris, G Broadwater

  • 1Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina 27710, USA.

Cancer Research
|April 18, 2001
PubMed

Insights

The antiestrogen GW5638 induces unique structural changes in the estrogen receptor (ER), offering a potential therapeutic for tamoxifen-resistant breast cancers. This drug is not cross-resistant with tamoxifen in resistant tumors.

Area of Science:

  • Endocrinology
  • Molecular Biology
  • Oncology

Background:

  • Tamoxifen inhibits estrogen receptor (ER) transcriptional activity.
  • Tamoxifen exhibits paradoxical agonist activity in certain tissues and breast tumors.
  • This suggests differential cellular recognition of the tamoxifen-ER complex.

Purpose of the Study:

  • To investigate the structural changes induced by the antiestrogen GW5638 in the ER.
  • To determine the biological significance of these conformational changes.
  • To evaluate GW5638 as a potential therapeutic for tamoxifen-resistant breast cancers.

Main Methods:

  • Phage display was utilized to identify structural changes in the ER induced by GW5638.
  • Studies were conducted on tamoxifen-resistant breast tumor explants.

Main Results:

  • GW5638 was demonstrated to induce a unique structural change in the ER.
  • Tamoxifen-resistant breast tumor explants showed no cross-resistance to GW5638.
  • This indicates a distinct mechanism of action compared to tamoxifen.

Conclusions:

  • The unique conformational change induced by GW5638 is biologically significant.
  • GW5638 represents a promising therapeutic candidate for tamoxifen-resistant breast cancers.
  • This drug offers a potential alternative treatment overcoming tamoxifen resistance.

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