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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

Estrogen receptors in resistance to hormone therapy

Matthew H Herynk1, Suzanne A W Fuqua

  • 1Breast Center, Baylor College of Medicine, Houston, Texas 77030, USA.

Advances in Experimental Medicine and Biology
|November 13, 2007
PubMed

Insights

Estrogen receptors (ER) are key in breast cancer, but tumors can become resistant to therapies like tamoxifen. This chapter explores molecular mechanisms driving this resistance, including ER mutations and signaling pathways.

Area of Science:

  • Oncology
  • Endocrinology
  • Molecular Biology

Background:

  • Estrogen receptors alpha and beta (ERalpha and ERbeta) are crucial in tumor progression, with two-thirds of breast cancers expressing functional ER.
  • The estrogen receptor (ER) is a primary target for breast cancer therapies.

Purpose of the Study:

  • To discuss molecular mechanisms underlying hormonal resistance in breast cancer therapies.
  • To explore the roles of ERalpha mutations, proliferation, apoptosis, and coregulator proteins in tamoxifen resistance.
  • To examine nonclassical ERalpha signaling and progesterone receptor involvement.

Main Methods:

  • Literature review and synthesis of current research on estrogen receptor signaling and breast cancer therapy resistance.
  • Analysis of molecular mechanisms including genetic mutations, cellular processes, and signaling pathways.

Main Results:

  • Hormonal therapies like tamoxifen are initially effective but resistance develops in many ER-positive tumors.
  • Mechanisms of resistance involve ERalpha mutations, altered proliferation and apoptosis, and coregulator protein activity.
  • Nonclassical ERalpha signaling via growth factor receptors and progesterone receptor roles also contribute to resistance.

Conclusions:

  • Understanding these resistance mechanisms is vital for developing more effective breast cancer treatments.
  • Targeting ERalpha mutations, signaling pathways, and coregulators may overcome tamoxifen resistance.
  • Further research into nonclassical ERalpha and progesterone receptor signaling is warranted.

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