Regulation of ERRalpha gene expression by estrogen receptor agonists and antagonists in SKBR3 breast cancer cells: differential molecular mechanisms mediated by g protein-coupled receptor GPR30/GPER-1.

  • Li Y
  • Birnbaumer L
  • Teng C
  • 1

    Readers

    Mendeley users who have this article in their library.
  • N/A

    Citations

    Citations of this article.

Abstract

In selected tissues and cell lines, 17beta-estradiol (E2) regulates the expression of estrogen-related receptor alpha (ERRalpha), a member of the orphan nuclear receptor family. This effect is thought to be mediated by the estrogen receptor alpha (ERalpha). However in the ERalpha- and ERbeta-negative SKBR3 breast cancer cell line, physiological levels of E2 also stimulate ERRalpha expression. Here, we explored the molecular mechanism that mediates estrogen action in ER-negative breast cancer cells. We observed that E2, the ERalpha agonist, as well as the ERalpha antagonists ICI 182,780 and tamoxifen (TAM), a selective ER modulator, stimulate the transcriptional activity of the ERRalpha gene and increase the production of ERRalpha protein in SKBR3 cells. Moreover, the ERRalpha downstream target genes expression and cellular proliferation are also increased. We show further that the G protein-coupled receptor GPR30/GPER-1 (GPER-1) mediates these effects. The GPER-1 specific ligand G-1 mimics the actions of E2, ICI 182,780, and TAM on ERRalpha expression, and changing the levels of GPER-1 mRNA by overexpression or small interfering RNA knockdown affected the expression of ERRalpha accordingly. Utilizing inhibitors, we delineate a different downstream pathway for ER agonist and ER antagonist-triggered signaling through GPER-1. We also find differential histone acetylation and transcription factor recruitment at distinct nucleosomes of the ERRalpha promoter, depending on whether the cells are activated with E2 or with ER antagonists. These findings provide insight into the molecular mechanisms of GPER-1/ERRalpha-mediated signaling and may be relevant to what happens in breast cancer cells escaping inhibitory control by TAM.

Author-supplied keywords

  • Acetylation/drug effects
  • Blotting
  • Breast Neoplasms/*genetics/metabolism
  • Cell Line
  • Chromatin Immunoprecipitation
  • Cyclopentanes/pharmacology
  • Estradiol/*analogs & derivatives/pharmacology
  • Estrogen/*agonists/*antagonists &
  • G-Protein-Coupled/genetics/*metabolism
  • Gene Expression/drug effects
  • Genetic/genetics
  • Histones/metabolism
  • Humans
  • Polymerase Chain Reaction
  • Promoter Regions
  • Protein Transport/drug effects/genetics
  • Quinolines/pharmacology
  • RNA Interference/physiology
  • Receptors
  • Tamoxifen/*pharmacology
  • Tumor
  • Western
  • inhibitors/genetics/metabolism

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Yin Li

  • Lutz Birnbaumer

  • Christina T Teng

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free