Estrogen action via the G protein-coupled receptor, GPR30: stimulation of adenylyl cyclase and cAMP-mediated attenuation of the epidermal growth factor receptor-to-MAPK signaling axis

Mol Endocrinol. 2002 Jan;16(1):70-84. doi: 10.1210/mend.16.1.0758.


Estrogen triggers rapid yet transient activation of the MAPKs, extracellular signal-regulated kinase (Erk)-1 and Erk-2. We have reported that this estrogen action requires the G protein-coupled receptor, GPR30, and occurs via Gbetagamma-subunit protein-dependent transactivation of the epidermal growth factor (EGF) receptor through the release of pro-heparan-bound EGF from the cell surface. Here we investigate the mechanism by which Erk-1/-2 activity is rapidly restored to basal levels after estrogen stimulation. Evidence is provided that attenuation of Erk-1/-2 activity by estrogen occurs via GPR30-dependent stimulation of adenylyl cyclase and cAMP-dependent signaling that results in Raf-1 inactivation. We show that 17beta-E2 represses EGF-induced activation of the Raf-to-Erk pathway in human breast carcinoma cells that express GPR30, including MCF-7 and SKBR3 cells which express both or neither, ER, respectively. MDA-MB-231 cells, which express ERbeta, but not ERalpha, and low levels of GPR30 protein, are unable to stimulate adenylyl cyclase or promote estrogen-mediated blockade of EGF-induced activation of Erk-1/-2. Pretreatment of MDA-MB-231 cells with cholera toxin, which ADP-ribosylates and activates Galphas subunit proteins, results in G protein-coupled receptor (GPCR)-independent adenylyl cyclase activity and suppression of EGF-induced Erk-1/-2 activity. Transfection of GPR30 into MDA-MB-231 cells restores their ability to stimulate adenylyl cyclase and attenuate EGF-induced activation of Erk-1/-2 by estrogen. Moreover, GPR30-dependent, cAMP-mediated attenuation of EGF-induced Erk-1/-2 activity was achieved by ER antagonists such as tamoxifen or ICI 182, 780; yet not by 17alpha-E2 or progesterone. Thus, our data delineate a novel mechanism, requiring GPR30 and estrogen, that acts to regulate Erk-1/-2 activity via an inhibitory signal mediated by cAMP. Coupled with our prior findings, these current data imply that estrogen balances Erk-1/-2 activity through a single GPCR via two distinct G protein-dependent signaling pathways that have opposing effects on the EGF receptor-to-MAPK pathway.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenylyl Cyclases / metabolism*
  • Breast Neoplasms / metabolism
  • Carbazoles*
  • Cyclic AMP / metabolism*
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors
  • ErbB Receptors / metabolism*
  • Estradiol / analogs & derivatives*
  • Estradiol / pharmacology
  • Estrogen Antagonists / pharmacology
  • Estrogens / metabolism*
  • Estrogens / pharmacology
  • Fulvestrant
  • Humans
  • Indoles / pharmacology
  • MAP Kinase Signaling System*
  • Mitogen-Activated Protein Kinase 1 / drug effects
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases / drug effects
  • Mitogen-Activated Protein Kinases / metabolism
  • Proto-Oncogene Proteins c-raf / drug effects
  • Proto-Oncogene Proteins c-raf / metabolism
  • Pyrroles / pharmacology
  • Receptors, Cell Surface / drug effects
  • Receptors, Cell Surface / metabolism*
  • Receptors, Estrogen
  • Receptors, G-Protein-Coupled*
  • Tamoxifen / pharmacology
  • Tumor Cells, Cultured


  • Carbazoles
  • Estrogen Antagonists
  • Estrogens
  • GPER1 protein, human
  • Indoles
  • Pyrroles
  • Receptors, Cell Surface
  • Receptors, Estrogen
  • Receptors, G-Protein-Coupled
  • Tamoxifen
  • Fulvestrant
  • Estradiol
  • KT 5720
  • Cyclic AMP
  • ErbB Receptors
  • Proto-Oncogene Proteins c-raf
  • Cyclic AMP-Dependent Protein Kinases
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases
  • Adenylyl Cyclases