1
|
Shomali M, Cheng J, Sun F, Koundinya M, Guo Z, Hebert AT, McManus J, Levit MN, Hoffmann D, Courjaud A, Arrebola R, Cao H, Pollard J, Lee JS, Besret L, Caron A, Bangari DS, Abecassis PY, Schio L, El-Ahmad Y, Halley F, Tabart M, Certal V, Thompson F, McCort G, Filoche-Rommé B, Cheng H, Garcia-Echeverria C, Debussche L, Bouaboula M. SAR439859, a Novel Selective Estrogen Receptor Degrader (SERD), Demonstrates Effective and Broad Antitumor Activity in Wild-Type and Mutant ER-Positive Breast Cancer Models. Mol Cancer Ther 2020; 20:250-262. [PMID: 33310762 DOI: 10.1158/1535-7163.mct-20-0390] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/31/2020] [Accepted: 11/03/2020] [Indexed: 11/16/2022]
Abstract
Primary treatment for estrogen receptor-positive (ER+) breast cancer is endocrine therapy. However, substantial evidence indicates a continued role for ER signaling in tumor progression. Selective estrogen receptor degraders (SERD), such as fulvestrant, induce effective ER signaling inhibition, although clinical studies with fulvestrant report insufficient blockade of ER signaling, possibly due to suboptimal pharmaceutical properties. Furthermore, activating mutations in the ER have emerged as a resistance mechanism to current endocrine therapies. New oral SERDs with improved drug properties are under clinical investigation, but the biological profile that could translate to improved therapeutic benefit remains unclear. Here, we describe the discovery of SAR439859, a novel, orally bioavailable SERD with potent antagonist and degradation activities against both wild-type and mutant Y537S ER. Driven by its fluoropropyl pyrrolidinyl side chain, SAR439859 has demonstrated broader and superior ER antagonist and degrader activities across a large panel of ER+ cells, compared with other SERDs characterized by a cinnamic acid side chain, including improved inhibition of ER signaling and tumor cell growth. Similarly, in vivo treatment with SAR439859 demonstrated significant tumor regression in ER+ breast cancer models, including MCF7-ESR1 wild-type and mutant-Y537S mouse tumors, and HCI013, a patient-derived tamoxifen-resistant xenograft tumor. These findings indicate that SAR439859 may provide therapeutic benefit to patients with ER+ breast cancer, including those who have resistance to endocrine therapy with both wild-type and mutant ER.
Collapse
Affiliation(s)
| | - Jane Cheng
- Sanofi, Research and Development, Cambridge, Massachusetts
| | - Fangxian Sun
- Sanofi, Research and Development, Cambridge, Massachusetts
| | | | - Zhuyan Guo
- Sanofi, Research and Development, Cambridge, Massachusetts
| | | | | | | | | | | | | | - Hui Cao
- Sanofi, Research and Development, Cambridge, Massachusetts
| | - Jack Pollard
- Sanofi, Research and Development, Cambridge, Massachusetts
| | - Joon Sang Lee
- Sanofi, Research and Development, Cambridge, Massachusetts
| | - Laurent Besret
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | - Anne Caron
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | | | | | - Laurent Schio
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | | | - Frank Halley
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | - Michel Tabart
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | - Victor Certal
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | | | - Gary McCort
- Sanofi, Research and Development, Vitry-sur-Seine, France
| | | | - Hong Cheng
- Sanofi, Research and Development, Cambridge, Massachusetts
| | | | | | | |
Collapse
|
2
|
Larson CJ, Osburn DL, Schmitz K, Giampa L, Mong SM, Marschke K, Seidel HM, Rosen J, Negro-Vilar A. Peptide Binding Identifies an ERα Conformation That Generates Selective Activity in Multiple In Vitro Assays. ACTA ACUST UNITED AC 2016; 10:590-8. [PMID: 16103420 DOI: 10.1177/1087057105275983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Drugs such as tamoxifen, which act at the estrogen receptor (ER), have very different in vitro and in vivo effects from those of the native hormone. Previous research has established that different ligands induce distinct conformational changes in the ER, thus affecting the interactions of the receptor with cell-specific coactivating or corepressing proteins (cofactors) and estrogen response elements (EREs), thus potentially driving differing biological effects. Affinity-selected peptides have been used to probe the conformational changes that occur within the ER upon binding various ligands. In this study, the authors characterize the ability of several peptides to be recruited to liganded ER under cellular conditions. Approximating ER conformation via recruitment of this peptide to the ER is concluded to be a better predictor of the agonist nature of an ER ligand under these different cellular contexts than is a canonical cotransfection transactivation assay.
Collapse
Affiliation(s)
- Christopher J Larson
- Department of Molecular & Cell Biology and New Leads Discovery Ligand Pharmaceuticals, San Diego, CA 92121, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Fahs S, Patil-Sen Y, Snape TJ. Foldamers as Anticancer Therapeutics: Targeting Protein-Protein Interactions and the Cell Membrane. Chembiochem 2015; 16:1840-1853. [DOI: 10.1002/cbic.201500188] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Indexed: 01/10/2023]
|
4
|
Oliva P, Roncoroni C, Radaelli E, Brunialti E, Rizzi N, De Maglie M, Scanziani E, Piaggio G, Ciana P, Komm B, Maggi A. Global Profiling of TSEC Proliferative Potential by the Use of a Reporter Mouse for Proliferation. Reprod Sci 2012; 20:119-28. [DOI: 10.1177/1933719111431002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Paolo Oliva
- TOP srl, Transgenic Operative Products, Lodi, Italy
| | | | - Enrico Radaelli
- DIPAV, Faculty of Veterinary Medicine, University of Milan, Milan, Italy
| | | | | | - Marcella De Maglie
- TOP srl, Transgenic Operative Products, Lodi, Italy
- DIPAV, Faculty of Veterinary Medicine, University of Milan, Milan, Italy
| | | | - Giulia Piaggio
- Experimental Oncology Department, Istituto Regina Elena, IRCCS, Rome, Italy
| | - Paolo Ciana
- Department of Pharmacological Sciences, University of Milan, Milan, Italy
| | - Barry Komm
- Pfizer Inc. (B.K.), Collegeville, Pennsylvania 19426, USA
| | - Adriana Maggi
- Department of Pharmacological Sciences, University of Milan, Milan, Italy
| |
Collapse
|
5
|
Sun M, Isaacs GD, Hah N, Heldring N, Fogarty EA, Kraus WL. Estrogen regulates JNK1 genomic localization to control gene expression and cell growth in breast cancer cells. Mol Endocrinol 2012; 26:736-47. [PMID: 22446103 DOI: 10.1210/me.2011-1158] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Steroid hormone and MAPK signaling pathways functionally intersect, but the molecular mechanisms of this cross talk are unclear. Here, we demonstrate a functional convergence of the estrogen and c-Jun N-terminal kinase 1 (JNK1) signaling pathways at the genomic level in breast cancer cells. We find that JNK1 binds to many promoters across the genome. Although most of the JNK1-binding sites are constitutive, a subset is estrogen regulated (either induced on inhibited). At the estrogen-induced sites, estrogen receptor (ER)α is required for the binding of JNK1 by promoting its recruitment to estrogen response elements or other classes of DNA elements through a tethering mechanism, which in some cases involves activating protein-1. At estrogen-regulated promoters, JNK1 functions as a transcriptional coregulator of ERα in a manner that is dependent on its kinase activity. The convergence of ERα and JNK1 at target gene promoters regulates estrogen-dependent gene expression outcomes, as well as downstream estrogen-dependent cell growth responses. Analysis of existing gene expression profiles from breast cancer biopsies suggests a role for functional interplay between ERα and JNK1 in the progression and clinical outcome of breast cancers.
Collapse
Affiliation(s)
- Miao Sun
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8511, USA
| | | | | | | | | | | |
Collapse
|
6
|
Fogarty EA, Matulis CK, Kraus WL. Activation of estrogen receptor α by raloxifene through an activating protein-1-dependent tethering mechanism in human cervical epithelial cancer cells: a role for c-Jun N-terminal kinase. Mol Cell Endocrinol 2012; 348:331-8. [PMID: 21964465 PMCID: PMC3217792 DOI: 10.1016/j.mce.2011.09.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 09/14/2011] [Accepted: 09/16/2011] [Indexed: 11/23/2022]
Abstract
Nuclear estrogen receptor α (ERα) regulates target gene expression in response to ligands through two distinct mechanisms: direct binding to DNA and indirect tethering through other DNA-bound transcription factors, such as AP-1. In the studies described herein, we examined the molecular mechanisms underlying the activation of ERα in the AP-1 tethering pathway by the selective estrogen receptor modulator (SERM) raloxifene (Ral). Our results with the MMP1 and PRUNE genes indicate that the c-Fos component of the AP-1 tethering factor and the c-Jun N-terminal kinase 1 (JNK1) are constitutively bound at the promoter regions prior to Ral exposure. Ral then promotes the binding of ERα at the promoter in a c-Fos-dependent manner. Interestingly, we found that JNK1 enzymatic activity is required for Ral-dependent gene activation through ERα. Our results suggest that one role for Ral-dependent recruitment of ERα to the AP-1 binding site is to stimulate JNK1 enzymatic activity. Alternatively, Ral-occupied ERα might recruit protein substrates to promoter-bound JNK1 without any change in JNK1 activity. Collectively, our studies have revealed a new role for JNK1 in determining gene regulatory outcomes by ERα.
Collapse
Affiliation(s)
- Elizabeth A. Fogarty
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Christina K. Matulis
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390-8511
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390-8511
| | - W. Lee Kraus
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390-8511
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390-8511
- Address correspondence to: W. Lee Kraus, Ph.D., Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, TX 75390-8511, Phone: 214-648-2388, Fax: 214-648-0383,
| |
Collapse
|
7
|
Li MJ, Greenblatt HM, Dym O, Albeck S, Pais A, Gunanathan C, Milstein D, Degani H, Sussman JL. Structure of estradiol metal chelate and estrogen receptor complex: the basis for designing a new class of selective estrogen receptor modulators. J Med Chem 2011; 54:3575-80. [PMID: 21473635 PMCID: PMC3112352 DOI: 10.1021/jm200192y] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Selective estrogen receptor modulators, such as 17β-estradiol derivatives bound to metal complexes, have been synthesized as targeted probes for the diagnosis and treatment of breast cancer. Here, we report the detailed 3D structure of estrogen receptor α ligand-binding domain (ERα-LBD) bound with a novel estradiol-derived metal complex, estradiol-pyridine tetra acetate europium(III), at 2.6 Å resolution. This structure provides important information pertinent to the design of novel functional ERα targeted probes for clinical applications.
Collapse
Affiliation(s)
- Min-Jun Li
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Harry M Greenblatt
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Orly Dym
- Israel Structural Proteomics Center (ISPC), Weizmann Institute of Science, Rehovot 76100, Israel
| | - Shira Albeck
- Israel Structural Proteomics Center (ISPC), Weizmann Institute of Science, Rehovot 76100, Israel
| | - Adi Pais
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
| | | | - David Milstein
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Hadassa Degani
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Joel L. Sussman
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel
- Israel Structural Proteomics Center (ISPC), Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
8
|
The gynecologic effects of lasofoxifene, an estrogen agonist/antagonist, in postmenopausal women. Menopause 2011; 18:6-7. [PMID: 21173718 DOI: 10.1097/gme.0b013e318203a46b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Peano BJ, Crabtree JS, Komm BS, Winneker RC, Harris HA. Effects of various selective estrogen receptor modulators with or without conjugated estrogens on mouse mammary gland. Endocrinology 2009; 150:1897-903. [PMID: 19022889 DOI: 10.1210/en.2008-1210] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Selective estrogen receptor modulators (SERMs) are small molecules that, depending on the end point measured, may either function as estrogen receptor (ER) agonists or antagonize estrogens' agonist activity. A key feature of SERMs is the inhibition of ER agonist action on the uterus and mammary gland, but the degree of antagonism varies among compounds and end points. Bazedoxifene is a SERM that is being clinically evaluated both as a monotherapy for the prevention and treatment of osteoporosis and in combination with conjugated estrogens (CEs) for the treatment of menopausal symptoms and prevention of osteoporosis. The studies reported here compare the relative ER agonist and antagonist effects of three pharmacologically distinct SERMs (bazedoxifene, raloxifene, and lasofoxifene) on the ovariectomized mouse when administered alone or as a tissue-selective estrogen complex, a term used to describe the partnering of a SERM and one or more estrogens. At the minimum dose required to maximally reduce CE-stimulated uterine wet weight increase for each SERM, the degree of inhibition varied among the SERMs, with a rank order of bazedoxifene approximately raloxifene > lasofoxifene, in which only bazedoxifene was statistically similar to vehicle. In the mammary gland, in which amphiregulin mRNA and morphological effects were measured, bazedoxifene generally exhibited less agonist activity and was a more effective antagonist of CE than raloxifene or lasofoxifene. In summary, in an animal model evaluating estrogen-modulated uterine effects and mammary gland development, bazedoxifene exhibited less ER agonist activity than raloxifene or lasofoxifene, and, as a tissue-selective estrogen complex, bazedoxifene/CE demonstrated less mammary gland stimulation than raloxifene/CE and lasofoxifene/CE.
Collapse
Affiliation(s)
- Bryan J Peano
- Department of Women's Health and Musculoskeletal Biology, Wyeth Research, Collegeville, Pennsylvania 19426, USA.
| | | | | | | | | |
Collapse
|
10
|
Rodriguez-Hernandez A, Rubio-Gayosso I, Ramirez I, Ita-Islas I, Meaney E, Gaxiola S, Meaney A, Asbun J, Figueroa-Valverde L, Ceballos G. Intraluminal-restricted 17 beta-estradiol exerts the same myocardial protection against ischemia/reperfusion injury in vivo as free 17 beta-estradiol. Steroids 2008; 73:528-38. [PMID: 18314151 DOI: 10.1016/j.steroids.2008.01.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2007] [Revised: 11/21/2007] [Accepted: 01/04/2008] [Indexed: 11/18/2022]
Abstract
Several in vitro studies show that in animals and isolated cells, 17 beta-estradiol induces cardiovascular protective effects and it has also been observed that it reduces coronary heart disease risk. However, the use of estrogens to improve or protect cardiovascular function in humans has been controversial, this might be explained by the wide variety of effects, because estrogen receptors (ER) are expressed ubiquitously. Therefore, a cell-specific targeting therapeutic approach might be necessary. 17 beta-Estradiol was coupled to a large modified dextran through an aminocaproic spacer. For this study we used intact and gonadectomized male Wistar rats, 15 days after surgical procedure. Intravascular administration of 17 beta-estradiol-macromolecular conjugate, prior to coronary reperfusion diminishes the area of damage induced by coronary ischemia reperfusion (I/R) injury on an in vivo model. This effect was observed at 17 beta-estradiol sub-physiological concentrations [0.01 nmol/L], it is mediated by luminal endothelial ER alpha activation. 17 beta-Estradiol-macromolecular conjugate decreases phosphorylation level of PKC alpha and Akt, as part of the process to induce myocardial protection against coronary I/R. We proved that the hormone-macromolecular conjugate labeled with [3H]estradiol remained confined in the intravascular space the conjugate was not internalized into organs like heart, lung or liver. It is noteworthy that the 17 beta-estradiol-macromolecular conjugate has a slow renal elimination, which might increase its pharmacological advantage. We concluded that the stimulus of endothelial estrogen receptors is enough to decrease the myocardial damage induced by coronary reperfusion.
Collapse
Affiliation(s)
- Arturo Rodriguez-Hernandez
- Seccion de Graduados, Escuela Superior de Medicina, Instituto Politecnico Nacional, 11340 Mexico City, Mexico
| | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Ho KJ, Liao JK. Non-nuclear actions of estrogen: new targets for prevention and treatment of cardiovascular disease. Mol Interv 2008; 2:219-28. [PMID: 14993393 PMCID: PMC2633129 DOI: 10.1124/mi.2.4.219] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Gender-based differences in the incidence of hypertensive and coronary artery disease, the development of atherosclerosis, and myocardial remodeling after infarction are attributable to the indirect effect of estrogen on risk factor profiles, such as cholesterol levels, glucose metabolism, and insulin levels. More recent evidence, however, suggests that activated estrogen receptor (ER) mediates signaling cascades that culminate in direct protective effects such as vasodilation, inhibition of response to vessel injury, limiting myocardial injury after infarction, and attenuating cardiac hypertrophy. Although the ER is usually thought of as a ligand-dependent transcription factor, it can also rapidly mobilize signals at the plasma membrane and in the cytoplasm. Thus, a greater understanding of ER function and regulation may lead to the development of highly specific therapeutics that mediate the prevention and treatment of cardiovascular diseases.
Collapse
Affiliation(s)
- Karen J Ho
- The Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, and Harvard Medical School, Cambridge, MA 02139, USA
| | | |
Collapse
|
12
|
de Araujo LFB, Grozovsky R, de Campos Pinheiro M, de Carvalho JJ, Vaisman M, Carvalho DP. Raloxifene effects on thyroid gland morphology in ovariectomized rats. Fertil Steril 2008; 90:1211-4. [PMID: 18178201 DOI: 10.1016/j.fertnstert.2007.10.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 10/16/2007] [Accepted: 10/16/2007] [Indexed: 11/25/2022]
Abstract
We aimed to analyze the effects of raloxifene and estrogen on thyroid gland morphology of ovariectomized rats. Raloxifene treatment led to effects similar to those of estrogen on thyroid glands from ovariectomized rats, so that both were able to normalize the changes detected after ovariectomy.
Collapse
Affiliation(s)
- Luiz Felipe Bittencourt de Araujo
- Laboratório de Fisiologia Endócrina, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil.
| | | | | | | | | | | |
Collapse
|
13
|
Kressler D, Hock MB, Kralli A. Coactivators PGC-1beta and SRC-1 interact functionally to promote the agonist activity of the selective estrogen receptor modulator tamoxifen. J Biol Chem 2007; 282:26897-26907. [PMID: 17631495 DOI: 10.1074/jbc.m705596200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PGC-1beta is a transcriptional coactivator that enhances strongly and in a hormone-dependent manner the activity of the estrogen receptor alpha (ERalpha) while having only weak effects on similar steroid hormone receptors, such as ERbeta or the glucocorticoid receptor. Notably, PGC-1beta enhances ERalpha transcriptional activity not only in response to agonist ligands, such as estradiol, but also to selective ER modulators, such as tamoxifen. Here, we dissect the molecular mechanisms underlying the ability of PGC-1beta to act selectively on ERalpha and to promote the agonist activity of tamoxifen. We show that receptor selectivity is achieved by PGC-1beta interactions with not just the ligand binding domain (LBD), which is highly conserved among nuclear receptors, but also the N-terminal domain and the hinge/AF-2a region of ERalpha, which are less well conserved. PGC-1beta interacts directly with the hinge/AF-2a and LBD regions but indirectly and via the coactivator SRC-1 with the N-terminal domain. The three ERalpha surfaces and SRC-1 collectively enable efficient coactivation by PGC-1beta. Similar ERalpha surfaces and interactions enable PGC-1beta to coactivate transcription by tamoxifen-bound ERalpha. Surprisingly, PGC-1beta coactivation of tamoxifen-bound ERalpha depends partially on one of the LXXLL motifs of PGC-1beta and on Lys(362) of the ERalpha LBD (i.e. surfaces implicated in agonist-dependent interactions). Our findings suggest that tamoxifen-induced changes in the ERalpha LBD promote interactions with the coactivator PGC-1beta, which then cooperates with SRC-1 to enable tamoxifen agonism.
Collapse
Affiliation(s)
- Dieter Kressler
- Division of Biochemistry, Biozentrum of the University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland
| | - M Benjamin Hock
- Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037
| | - Anastasia Kralli
- Division of Biochemistry, Biozentrum of the University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland; Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037.
| |
Collapse
|
14
|
Jones MB, Houwink AP, Freeman BK, Greenwood TM, Lafky JM, Lingle WL, Berchuck A, Maxwell GL, Podratz KC, Maihle NJ. The granulin-epithelin precursor is a steroid-regulated growth factor in endometrial cancer. ACTA ACUST UNITED AC 2006; 13:304-11. [PMID: 16697948 DOI: 10.1016/j.jsgi.2006.03.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2005] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The majority of endometrial cancers arise as a result of estrogen stimulation, the molecular targets of which remain incompletely defined. We hypothesize that the granulin-epithelin precursor (GEP) may be one such target. In this study, we examined the frequency of GEP and estrogen receptor (ER) co-expression in human endometrial cancers. Once we established the co-expression of GEP with the estrogen receptor we examined the potential estrogen regulation of GEP expression, as well as the functional significance of GEP expression in vitro. METHODS Double immunofluorescence and confocal microscopy were used to compare GEP and ER expression among 41 endometrial cancers. The effects of estradiol and tamoxifen treatment on GEP expression in two endometrial cancer cell lines, KLE and HEC-1-A, were assessed through reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis. The antiproliferative effect of GEP silencing by short hairpin (sh)RNA, was evaluated in HEC-1-A cells using an MTT assay. RESULTS GEP co-expression with ER was observed in 63% of the cancers examined. A two- to fivefold increase in GEP expression with estradiol and/or tamoxifen treatment was observed in KLE cells. Silencing of GEP in HEC-1-A cells using shRNA resulted in a decrease in proliferation among transfected cells. CONCLUSIONS Co-expression of GEP and ER in endometrial cancer cells, and the regulation of GEP by estrogen, suggests a role for GEP in steroid-mediated endometrial cancer cell growth. Further characterization of GEP as a steroid-mediated growth factor in these cells may broaden our understanding of endometrial cancer biology and also provide guidance in the development of novel therapeutic targets.
Collapse
|
15
|
Taneja SS, Smith MR, Dalton JT, Raghow S, Barnette G, Steiner M, Veverka KA. Toremifene--a promising therapy for the prevention of prostate cancer and complications of androgen deprivation therapy. Expert Opin Investig Drugs 2006; 15:293-305. [PMID: 16503765 DOI: 10.1517/13543784.15.3.293] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Deregulation of the estrogen axis in humans prompts a series of tissue-specific events. In the breast and prostate, alterations in estrogen signalling lead to genotypic and phenotypic molecular alterations that result in dysplastic cellular appearance, deregulated cell growth and carcinoma. In bone, decreased estrogen leads to increased osteoclastogenesis and bone resorption, decreased bone mineral density and a significant fracture risk. Toremifene is a selective estrogen receptor modulator that exerts pharmacological activity in the breast, bone and prostate. An intense interest in developing this agent for prostate cancer chemoprevention is based on the reduction of premalignant and malignant prostate lesions in a transgenic model of prostate cancer. Biological and clinical activity was demonstrated in Phase II trials by the prevention of progression to prostate cancer in men with high-grade prostate intraepithelial neoplasia and through suppression of bone turnover biomarkers and increased bone mineral density in men on androgen deprivation therapy for prostate cancer.
Collapse
Affiliation(s)
- Samir S Taneja
- New York University School of Medicine, New York, NY 10016, USA
| | | | | | | | | | | | | |
Collapse
|
16
|
Wessler S, Otto C, Wilck N, Stangl V, Fritzemeier KH. Identification of estrogen receptor ligands leading to activation of non-genomic signaling pathways while exhibiting only weak transcriptional activity. J Steroid Biochem Mol Biol 2006; 98:25-35. [PMID: 16203130 DOI: 10.1016/j.jsbmb.2005.08.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Accepted: 08/11/2005] [Indexed: 12/27/2022]
Abstract
Estrogen receptors (ERs) stimulate genomic effects by acting as nuclear transcription factors as well as non-genomic effects by activating distinct cytoplasmic protein kinase cascades. Non-genomic effects have been implicated in numerous cellular processes, such as proliferation, differentiation, apoptosis and vasorelaxation. To exploit non-genomic effects mediated by ERalpha for novel hormone replacement regimens, we screened a focused library of steroid receptor ligands to identify compounds exhibiting properties different from estradiol, i.e. substances that selectively stimulate non-genomic signal transduction pathways while exhibiting low genomic activities. Treatment of breast cancer cells and osteosarcoma cells with estradiol, estren, substance A and substance B led to non-genomic activation of Akt (protein kinase B) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling cascades mediated by Src (Rous Sarcoma Virus, non-receptor tyrosine kinase) and phosphatidylinositol-3-kinase (PI3K) stimulation. Such compounds leading to prominent Akt/ERK activation but exhibiting only weak genomic properties were applied in vasorelaxation assays, modeling physiological non-genomic ER responses. As expected from PI3K and Src activation data, substances were as effective as estradiol in mediating vasorelaxation. We assume that these pathway-selective estrogen receptor ligands may serve as potent lead structures for novel hormone replacement strategies exhibiting lesser side effects than the existing treatment paradigms.
Collapse
Affiliation(s)
- Silja Wessler
- Paul-Ehrlich-Institute, Paul-Ehrlich Strasse 51-59, D-63225 Langen, Germany.
| | | | | | | | | |
Collapse
|
17
|
Galande AK, Bramlett KS, Trent JO, Burris TP, Wittliff JL, Spatola AF. Potent Inhibitors of LXXLL-Based Protein-Protein Interactions. Chembiochem 2005; 6:1991-8. [PMID: 16222726 DOI: 10.1002/cbic.200500083] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Protein-protein interactions between estrogen receptors, ERalpha and ERbeta, and their coactivators (CoAs) are an attractive target for drug intervention. This interaction is mediated by a small pentapeptide motif (LXXLL), termed the NR box. Based on this motif, a variety of cyclic and linear peptides were synthesized in order to gain a better understanding of the association of CoA proteins with the ER isoforms. Utilizing a time-resolved florescence-based coactivator interaction assay, we determined the abilities of these peptides to inhibit this interaction. Using molecular modeling and CD spectroscopy, we have examined the structural basis of their bioactivities with both hormone receptor isoforms. Either homocysteine or penicillamine was utilized as a substitute for cysteine in the disulfide-bridged peptides, while tertiary leucine and neopentyl glycine were used as the surrogates for the NR box leucines. The most potent disufide-bridged peptide (K(i)= 70 pM, with ERalpha) incorporates neopentyl glycine in the NR box, while the most active peptide in this series with ERbeta (K(i)=350 pM) incorporates tertiary leucine. Surprisingly, several linear peptides containing a single cysteine residue showed activities with low nanomolar K(i) values. Collectively, our results suggest a synthetic approach for designing potent and selective peptidomimetics for ERalpha and ERbeta interactions with CoA proteins effecting estrogen action.
Collapse
Affiliation(s)
- Amit K Galande
- Department of Chemistry, University of Louisville, Louisville, KY 40292, USA
| | | | | | | | | | | |
Collapse
|
18
|
De S, Macara IG, Lannigan DA. Novel biosensors for the detection of estrogen receptor ligands. J Steroid Biochem Mol Biol 2005; 96:235-44. [PMID: 15985367 DOI: 10.1016/j.jsbmb.2005.04.030] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2004] [Accepted: 04/08/2005] [Indexed: 11/29/2022]
Abstract
There exists a significant need for the detection of novel estrogen receptor (ER) ligands for pharmaceutical uses, especially for treating complications associated with menopause. We have developed fluorescence resonance energy transfer (FRET)-based biosensors that permit the direct in vitro detection of ER ligands. These biosensors contain an ER ligand-binding domain (LBD) flanked by the FRET donor fluorophore, cyan fluorescent protein (CFP), and the acceptor fluorophore, yellow fluorescent protein (YFP). The ER-LBD has been modified so that Ala 430 has been changed to Asp, which increases the magnitude of the FRET signal in response to ligand-binding by more than four-fold compared to the wild-type LBD. The binding of agonists can be distinguished from that of antagonists on the basis of the distinct ligand-induced conformations in the ER-LBD. The approach to binding equilibrium occurs within 30min, and the FRET signal is stable over 24h. The biosensor demonstrates a high signal-to-noise, with a Z' value (a statistical determinant of assay quality) of 0.72. The affinity of the ER for different ligands can be determined using a modified version of the biosensor in which a truncated YFP and an enhanced CFP are used. Thus, we have developed platforms for high-throughput screens for the identification of novel estrogen receptor ligands. Moreover, we have demonstrated that this FRET technology can be applied to other nuclear receptors, such as the androgen receptor.
Collapse
Affiliation(s)
- Siddhartha De
- Luna Innovations, Inc., Charlottesville, VA 22903, USA
| | | | | |
Collapse
|
19
|
Lim HJ, Cho JS, Oh JH, Shim SB, Hwang DY, Jee SW, Lee SH, Sheen YY, Lee SH, Kim YK. NSE-Controlled Carboxyl-Terminus of APP Gene Over-Expressing in Transgenic Mice Induces Altered Expressions in Behavior, Aβ-42, and GSK3β Binding Proteins. Cell Mol Neurobiol 2005; 25:833-50. [PMID: 16133937 DOI: 10.1007/s10571-005-4937-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2004] [Accepted: 12/22/2004] [Indexed: 11/26/2022]
Abstract
The amyloid protein precursor (APP) is cleaved in its intramembranous domain by gamma-secrease to generate amyloid beta and a free carboxyl-terminal intracellular fragment. The carboxyl-terminal of 105 amino acids of APP (APP-C105) plays a crucial role in the neuropathology of Alzheimer's disease (AD), but it is incompletely understand how APP-C105 overexpression interacts and regulates the brain function and Abeta-42 levels, and whether or not it is associated with the expressions of GSK3beta-binding proteins. To test this, transgenic mice expressing NSE-controlled APP-C105 were produced and tested for their above phenotypes. A behavioral deficit was observed in the 9 months old transgenic mice, and western blot indicated that there was a predominant expression of APP-C105 in transgenic brains compared with those of non-transgenic brains. In parallel, APP-C105 overexpression resulted in the modulation of the Abeta-42 level, gamma-secretase activity, GSK3beta-binding proteins including PS1, tau, and beta-catenin in the brains of the transgenic mice relative to the non-transgenic mice. Thus, altered expressions of these neuropathological phenotypes in APP-C105 transgenic mice could be useful targets in developing new therapeutic treatments.
Collapse
Affiliation(s)
- Hwa J Lim
- Division of Laboratory Animal Resources, Korea Food and Drug Administration, National Institute of Toxicological Research, 5 Nokbun-dong Eunpyng-ku, Seoul 122-704, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Bergasa NV, Mason A, Floreani A, Heathcote J, Swain MG, Jones DEJ, Lindor KM, Bassendine MF, Worman HJ. Primary biliary cirrhosis: report of a focus study group. Hepatology 2004; 40:1013-20. [PMID: 15382160 DOI: 10.1002/hep.20446] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Affiliation(s)
- Nora V Bergasa
- State University of New York, Downstate Medical Center, Brooklyn, NY 11203, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease, which predominantly affects women. It is characterised histologically by necroinflammation of small intrahepatic bile ducts and biochemically by elevated serum alkaline phosphatase, levels of which at diagnosis predict survival. Ursodeoxycholic acid (UDCA) is the only treatment shown to improve liver biochemistry and survival. We report two patients with PBC who show a fall in serum alkaline phosphates levels whilst receiving tamoxifen therapy. Tamoxifen may exert this effect, which warrants further study, either via cholangiocyte estrogen receptors, inhibiting cholangiocyte proliferation and inducing apoptosis or by activating pregnane X receptor, analogous to the mode of action of UDCA.
Collapse
Affiliation(s)
- A Reddy
- Freeman Hospital Liver Unit, Newcastle upon Tyne Hospitals Trust, UK
| | | | | | | | | |
Collapse
|
22
|
Draper MW. The Role of Selective Estrogen Receptor Modulators (SERMs) in Postmenopausal Health. Ann N Y Acad Sci 2003; 997:373-7. [PMID: 14644844 DOI: 10.1196/annals.1290.040] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Concerns about long-term therapy with HRT have recently highlighted interest in a class of compounds active in the estrogen receptor, but with selectivity in their actions, known as the selective estrogen receptor modulators (SERMs). Tamoxifen is recognized as the first widely marketed SERM, but its selectivity focuses interest on its approved indications: the treatment and prevention of breast cancer. Raloxifene has been approved in most countries of the world for the treatment and prevention of osteoporosis, and it displays a pattern of actions highly matched to the needs and concerns of many postmenopausal women. Further study of current and future SERMs promises to open new vistas in patient-specific management of the field of postmenopausal health.
Collapse
Affiliation(s)
- Michael W Draper
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, DC 2138, Indianapolis, IN 46285, USA.
| |
Collapse
|
23
|
Stygar D, Muravitskaya N, Eriksson B, Eriksson H, Sahlin L. Effects of SERM (selective estrogen receptor modulator) treatment on growth and proliferation in the rat uterus. Reprod Biol Endocrinol 2003; 1:40. [PMID: 12777179 PMCID: PMC156658 DOI: 10.1186/1477-7827-1-40] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2003] [Accepted: 05/07/2003] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Selective estrogen receptor modulators (SERMs) have been developed in order to create means to control estrogenic effects on different tissues. A major drawback in treatment of estrogen receptor (ER) positive breast cancer with the antagonist tamoxifen (TAM) is its agonistic effect in the endometrium. Raloxifene (RAL) is the next generation of SERMs where the agonistic effect on the endometrium has been reduced. METHODS The aim of the present study was to determine the effect of SERM treatment on the uterus, as assessed by proliferation markers and several factors involved in uterine growth. Ovariectomized (ovx) rats were treated with estradiol (E2), tamoxifen (TAM), RAL, ICI182780 (ICI) or vehicle (OVX-controls). We studied the effects on mRNA levels of the growth hormone (GH) receptor, insulin-like growth factor-I (IGF-I), ERalpha and ERbeta. In addition, by immunohistochemistry the proliferation markers PCNA and Ki-67, as well as ERalpha and ERbeta, were detected. RESULTS The uterine weight of the rats treated with E2 or TAM was increased as compared to OVX-controls. The uterine GH-receptor mRNA level was highest in the E2 treated animals. In ICI treated rats no GH-receptor mRNA could be detected. The IGF-I mRNA level increased 16-fold in uteri of the TAM treated group and 9-fold in the E2 treated rats as compared to OVX-controls. The ERalpha mRNA level was increased in the E2 treated rats, while the ERbeta mRNA level was increased after TAM treatment. The proliferation, as assessed by PCNA, was lowest in ICI treated animals. CONCLUSIONS The uterine wet weight, the LE height and the GH-receptor mRNA levels showed similar patterns, indicating that GH is involved in the regulation of uterine weight. Tamoxifen, which has been related to increased incidence of endometrial carcinoma in women, dramatically increased IGF-I mRNA levels in rat uterus. Since proliferation was not higher in TAM and E2 treated rats than in OVX controls, this assay of simple, early proliferation does not give the full explanation of why TAM should enhance the risk of developing endometrial cancer.
Collapse
Affiliation(s)
- Denis Stygar
- Division for Reproductive Endocrinology, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden
| | - Natalia Muravitskaya
- Division for Reproductive Endocrinology, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden
| | - Britt Eriksson
- Division for Reproductive Endocrinology, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden
| | - Håkan Eriksson
- Division for Reproductive Endocrinology, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden
| | - Lena Sahlin
- Division for Reproductive Endocrinology, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|