The objective of this investigation is to determine the molecular and structural distinctions between estrogen agonism and antagonism in hormone dependent tissues and cancers and to identify, develop and characterize novel compounds that have desired tissue-selective estrogenic or antiestrogenic properties. Because these effects are mediated by one or both of the two estrogen receptors, ERa and ER(J, knowledge of the induced conformational changes of receptor-ligand complexes and analysis of behavior profiles for novel receptor ligands is essential for developing selective estrogen receptor modulators (SERMs). Therefore, a major goal of this project is to correlate compound behavior in vitro and in vivo with the crystallographic structures of ERa and ER(3 bound to novel steroidal and nonsteroidal SERMs. This information will be used to help modify or design compounds with predictable, altered pharmacological properties. To accomplish these goals we will: 1) Determine the detailed crystallographic structures of the human ERa and ER(5 proteins, including the LBDs and additional functional domains up to full-length receptor, in combination with known and novel SERMs with unique tissue-selective and receptor-selective properties. Crystallizations will be assisted by the inclusion of coregulator peptides and/or crystallization chaperones (Fab and FN3 monobody) to stabilize ER complexes. Structure guided mutagenesis will be used to define important contacts within and between functional domains. This information will be used to modify and/or design ligands with altered pharmacological properties. 2) Characterize novel ERa and/or ER0- selective ligands in in vitro and in hormone-sensitive animal tumor models, especially SCID mouse xenografts and C3(1)/SV40 T-antigen transgenic mice that develop spontaneous mammary tumors. To determine potential therapeutic utility, we will also study the in vivo pharmacology of candidate ligands in rats and mice by measuring uterotrophic response, cholesterol levels, and bone density. This behavior will be compared with the activities of both ERs in reporter assays of estrogen responsive promoters in transfected cells. The characterization of ER subtype-specific interactions will facilitate the identification and/or creation of new compounds that act differently on ERa and ER3 and possess novel therapeutic properties. Detailed structure information will also help reveal the molecular basis for such behavior. It is anticipated that compounds derived from this study may have application in the treatment and/or prevention of hormone sensitive cancers, especially breast cancer, and may also have utility as agents for hormone replacement therapy.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA089489-10
Application #
8063087
Study Section
Molecular and Cellular Endocrinology Study Section (MCE)
Program Officer
Perloff, Marjorie
Project Start
2000-12-01
Project End
2013-04-30
Budget Start
2011-05-01
Budget End
2013-04-30
Support Year
10
Fiscal Year
2011
Total Cost
$403,332
Indirect Cost
Name
University of Chicago
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
005421136
City
Chicago
State
IL
Country
United States
Zip Code
60637
Bourgo, Ryan J; Singhal, Hari; Greene, Geoffrey L (2016) Capture of associated targets on chromatin links long-distance chromatin looping to transcriptional coordination. Nat Commun 7:12893
Le, Thien P; Sun, Miao; Luo, Xin et al. (2013) Mapping ER? genomic binding sites reveals unique genomic features and identifies EBF1 as an ER? interactor. PLoS One 8:e71355
O'Leary, Kathleen A; Jallow, Fatou; Rugowski, Debra E et al. (2013) Prolactin activates ER? in the absence of ligand in female mammary development and carcinogenesis in vivo. Endocrinology 154:4483-92
Balbas, Minna D; Evans, Michael J; Hosfield, David J et al. (2013) Overcoming mutation-based resistance to antiandrogens with rational drug design. Elife 2:e00499
Walker, M P; Zhang, M; Le, T P et al. (2011) RAC3 is a pro-migratory co-activator of ERýý. Oncogene 30:1984-94
Leong, Hoyee; Mathur, Priya S; Greene, Geoffrey L (2009) Green tea catechins inhibit angiogenesis through suppression of STAT3 activation. Breast Cancer Res Treat 117:505-15
Nettles, Kendall W; Gil, German; Nowak, Jason et al. (2008) CBP Is a dosage-dependent regulator of nuclear factor-kappaB suppression by the estrogen receptor. Mol Endocrinol 22:263-72
O'Neill, Erin E; Blewett, Alexis R; Loria, Paula M et al. (2008) Modulation of alphaCaMKII signaling by rapid ERalpha action. Brain Res 1222:1-17
Nettles, Kendall W; Bruning, John B; Gil, German et al. (2008) NFkappaB selectivity of estrogen receptor ligands revealed by comparative crystallographic analyses. Nat Chem Biol 4:241-7
Hsieh, Robert W; Rajan, Shyamala S; Sharma, Sanjay K et al. (2008) Molecular characterization of a B-ring unsaturated estrogen: implications for conjugated equine estrogen components of premarin. Steroids 73:59-68

Showing the most recent 10 out of 18 publications