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mTOR/S6K1 and MAPK/RSK signaling pathways coordinately regulate estrogen receptor alpha serine 167 phosphorylation

Rachel L Yamnik1, Marina K Holz

  • 1Department of Biology, Stern College for Women of Yeshiva University, New York, NY 10016, USA.

FEBS Letters
|November 21, 2009
PubMed

Insights

Estrogen receptor alpha (ERalpha) phosphorylation at Ser167 drives anti-estrogen therapy resistance in breast cancer. Targeting both mTOR and MAPK pathways may overcome this resistance.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Signaling

Background:

  • Anti-estrogen therapy resistance is a significant challenge in breast cancer treatment.
  • Estrogen receptor alpha (ERalpha) phosphorylation, particularly at Ser167, is linked to resistance and serves as a prognostic marker.

Purpose of the Study:

  • To investigate the signaling pathways regulating ERalpha Ser167 phosphorylation.
  • To identify potential therapeutic targets for overcoming anti-estrogen resistance.

Main Methods:

  • Dissection of signaling cascades upstream of ERalpha phosphorylation.
  • Analysis of the roles of mTOR/S6K1 and MAPK/RSK pathways in ERalpha activation.

Main Results:

  • Identified non-overlapping contributions of mTOR/S6K1 and MAPK/RSK pathways to ERalpha Ser167 phosphorylation.
  • Demonstrated that these pathways cooperate to activate ERalpha, promoting resistance.

Conclusions:

  • The mTOR/S6K1 and MAPK/RSK pathways are key regulators of ERalpha phosphorylation at Ser167.
  • Combined inhibition of mTOR and MAPK signaling presents a potential therapeutic strategy for resistant breast cancer.

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