Estrogen and its receptors are critical factors in the development, progression, metastasis and treatment of breast cancer. In addition to the classical nuclear estrogen receptors, ERalpha and ERbeta, the 7-transmembrane G protein-coupled estrogen receptor GPER is now recognized as mediating many of the rapid signaling events associated with estrogen action. Anti-estrogen therapies in the form of selective estrogen receptor modulators (SERMs, such as tamoxifen) and selective estrogen receptor down regulators (SERDs, such as Fulvestrant) have been highly successful in many ER-positive breast cancer patients; however, intrinsic and acquired resistance remains significant problems. Tamoxifen and Fulvestrant are agonists of GPER, suggesting that GPER may play a role in resistance to these drugs. We have identified both a selective agonist and antagonists of GPER that will allow us to test the hypothesis that GPER plays an important role in breast carcinogenesis and treatment efficacy.
Aim 1 will test whether GPER mediates cellular effects including proliferation, survival, transformation and migration in response to estrogen, anti-estrogens and GPER-selective ligands.
Aim 2 will test whether selective targeting of GPER activity modulates carcinogenesis and metastasis in a murine model of breast cancer.
Aim 3 will test whether selective activation and inhibition of GPER regulates proliferation and survival of cells in normal human breast tissue and human breast tumor explants. Significance: Completion of these aims will significantly advance our knowledge of and provide insight into the role of the novel estrogen receptor GPER in multiple aspects of breast cancer, from initiation to metastasis and drug resistance resulting in the identification of a novel therapeutic target for which highly selective antagonists exist. Further development of this antagonist could lead to a new drug for the treatment of GPER-expressing breast tumors.

Public Health Relevance

Estrogen and its receptors play important roles in breast cancer and are the targets of multiple therapies in breast cancer. Although often initially effective, resistance to drugs such as tamoxifen is a common problem. This study will determine the role of a novel estrogen receptor in breast cancer formation, progression and metastasis and test the ability of unique inhibitors of this receptor to prevent, cure or reduce the severity f this cancer.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Project (R01)
Project #
Application #
Study Section
Tumor Progression and Metastasis Study Section (TPM)
Program Officer
Ault, Grace S
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of New Mexico Health Sciences Center
Anatomy/Cell Biology
Schools of Medicine
United States
Zip Code
Castleman, Moriah J; Pokhrel, Srijana; Triplett, Kathleen D et al. (2018) Innate Sex Bias of Staphylococcus aureus Skin Infection Is Driven by ?-Hemolysin. J Immunol 200:657-668
Barton, Matthias; Filardo, Edward J; Lolait, Stephen J et al. (2018) Twenty years of the G protein-coupled estrogen receptor GPER: Historical and personal perspectives. J Steroid Biochem Mol Biol 176:4-15
Prossnitz, Eric R (2018) GPER modulators: Opportunity Nox on the heels of a class Akt. J Steroid Biochem Mol Biol 176:73-81
Arias-Pulido, H; Cimino-Mathews, A; Chaher, N et al. (2018) The combined presence of CD20?+?B cells and PD-L1?+?tumor-infiltrating lymphocytes in inflammatory breast cancer is prognostic of improved patient outcome. Breast Cancer Res Treat 171:273-282
Peretti, Amanda S; Dominguez, Dayna; Grimes, Martha M et al. (2018) The R-Enantiomer of Ketorolac Delays Mammary Tumor Development in Mouse Mammary Tumor Virus-Polyoma Middle T Antigen (MMTV-PyMT) Mice. Am J Pathol 188:515-524
Prossnitz, Eric R (2018) New developments in the rapid actions of steroids and their receptors. J Steroid Biochem Mol Biol 176:1-3
Sharma, Geetanjali; Mauvais-Jarvis, Franck; Prossnitz, Eric R (2018) Roles of G protein-coupled estrogen receptor GPER in metabolic regulation. J Steroid Biochem Mol Biol 176:31-37
Marcus, Jenna Z; Klobocista, Merieme; Karabakhtsian, Rouzan G et al. (2018) Female Sex Hormone Receptor Profiling in Uterine Adenosarcomas. Int J Gynecol Cancer 28:500-504
Hill, Deirdre A; Friend, Sarah; Lomo, Lesley et al. (2018) Breast cancer survival, survival disparities, and guideline-based treatment. Breast Cancer Res Treat 170:405-414
Fredette, Natalie C; Meyer, Matthias R; Prossnitz, Eric R (2018) Role of GPER in estrogen-dependent nitric oxide formation and vasodilation. J Steroid Biochem Mol Biol 176:65-72

Showing the most recent 10 out of 37 publications