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Negative regulation of ERα by a novel protein CAC1 through association with histone demethylase LSD1

JuHyun Kim1, Ui-Hyun Park, MinO Moon

  • 1Department of Molecular Biology, BK21 Graduate Program, Dankook University, Yongin-si, Gyeonggi-do 448-701, Republic of Korea.

FEBS Letters
|November 27, 2012
PubMed

Insights

Researchers discovered CAC1, a novel corepressor for estrogen receptor alpha (ERα). CAC1, working with LSD1, inhibits ERα activity and enhances chemotherapy in ERα-positive breast cancer.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Epigenetics

Background:

  • Estrogen receptor alpha (ERα) is a key driver of breast cancer proliferation.
  • ERα activity is modulated by coactivators and corepressors.

Purpose of the Study:

  • To identify novel ERα coregulators.
  • To investigate the function of CAC1 in ERα regulation and breast cancer.

Main Methods:

  • Co-immunoprecipitation assays to study protein interactions.
  • Chromatin immunoprecipitation (ChIP) to assess promoter recruitment and histone modifications.
  • Cell viability assays to evaluate drug response.

Main Results:

  • CAC1 binds to ERα via its CoRNR box, inhibiting ERα activity.
  • CAC1 interacts with histone demethylase LSD1, suppressing its pro-tumorigenic effects.
  • CAC1 depletion reverses the observed effects, indicating its crucial role.
  • CAC1 enhances paclitaxel-induced cell death in paclitaxel-resistant MCF7 cells.

Conclusions:

  • CAC1 functions as a novel ERα corepressor, collaborating with LSD1.
  • CAC1 represents a potential therapeutic target for ERα-positive breast cancer.

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