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Updated: May 23, 2026

Detecting the Ligand-binding Domain Dimerization Activity of Estrogen Receptor Alpha Using the Mammalian Two-Hybrid Assay
09:07

Detecting the Ligand-binding Domain Dimerization Activity of Estrogen Receptor Alpha Using the Mammalian Two-Hybrid Assay

Published on: December 19, 2018

Phosphorylation by p38 mitogen-activated protein kinase promotes estrogen receptor α turnover and functional activity

Shweta Bhatt1, Zhen Xiao, Zhaojing Meng

  • 1Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.

Molecular and Cellular Biology
|March 21, 2012
PubMed

Insights

Researchers discovered a new pathway regulating estrogen receptor alpha (ERα) levels in breast cancer. This involves p38MAPK and Skp2, offering potential to restore endocrine therapy sensitivity in resistant tumors.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Endocrinology

Background:

  • Estrogen receptor alpha (ERα) is key for breast cancer cell growth and endocrine therapy response.
  • Loss of ERα is linked to endocrine resistance, but its regulation is not fully understood.

Purpose of the Study:

  • To elucidate the molecular mechanisms controlling ERα cellular levels.
  • To identify potential therapeutic targets for endocrine-insensitive breast cancers.

Main Methods:

  • Investigated the role of p38MAPK-mediated phosphorylation of ERα at Ser-294.
  • Assessed the involvement of the SCF(Skp2) proteasome complex in ERα degradation.
  • Utilized knockdown and inhibition strategies in breast cancer cell lines and human tumors.

Main Results:

  • Identified a novel pathway where p38MAPK phosphorylates ERα, targeting it for SCF(Skp2) proteasome degradation.
  • Observed an inverse correlation between ERα levels and Skp2 or active p38MAPK in breast cancer.
  • Restored ERα function and estrogen responsiveness by inhibiting p38MAPK or knocking down Skp2.

Conclusions:

  • ERα turnover is regulated by a p38MAPK-Skp2-proteasome pathway, crucial for breast cancer proliferation.
  • This pathway represents a potential therapeutic target to restore ERα levels and endocrine therapy sensitivity in resistant breast cancers.

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