401
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402
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Tiraby C, Hazen BC, Gantner ML, Kralli A. Estrogen-related receptor gamma promotes mesenchymal-to-epithelial transition and suppresses breast tumor growth. Cancer Res 2011; 71:2518-28. [PMID: 21339306 DOI: 10.1158/0008-5472.can-10-1315] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Estrogen-related receptors (ERR), ERR alpha (ERRα) and ERR gamma (ERRγ), are orphan nuclear receptors implicated in breast cancer that function similarly in the regulation of oxidative metabolism genes. Paradoxically, in clinical studies, high levels of ERRα are associated with poor outcomes whereas high levels of ERRγ are associated with a favorable course. Recent studies suggest that ERRα may indeed promote breast tumor growth. The roles of ERRγ in breast cancer progression and how ERRα and ERRγ may differentially affect cancer growth are unclear. In mammary carcinoma cells that do not express endogenous ERRγ, we found that ectopic expression of ERRγ enhanced oxidative metabolism in vitro and inhibited the growth of tumor xenografts in vivo. In contrast, ectopic expression of the ERRα coactivator PGC-1α enhanced oxidative metabolism but did not affect tumor growth. Notably, ERRγ activated expression of a genetic program characteristic of mesenchymal-to-epithelial transition (MET). This program was apparent by changes in cellular morphology, upregulation of epithelial cell markers, downregulation of mesenchymal markers, and decreased cellular invasiveness. We determined that this program was also associated with upregulation of E-cadherin, which is activated directly by ERRγ. In contrast, PGC-1α activated only a subset of genes characteristic of the MET program and, unlike ERRγ, did not upregulate E-cadherin. In conclusion, these results show that ERRγ induces E-cadherin, promotes MET, and suppresses breast cancer growth. Our findings suggest that ERRγ agonists may have applications in the treatment of breast cancer.
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Affiliation(s)
- Claire Tiraby
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California, USA
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403
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Mapping of INS promoter interactions reveals its role in long-range regulation of SYT8 transcription. Nat Struct Mol Biol 2011; 18:372-8. [PMID: 21336277 PMCID: PMC6402586 DOI: 10.1038/nsmb.1993] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 11/30/2010] [Indexed: 02/07/2023]
Abstract
Insulin (INS) synthesis and secretion from pancreatic β cells are tightly regulated; their deregulation causes diabetes. Here we map INS-associated loci in human pancreatic islets by 4C and 3C techniques and show that the INS gene physically interacts with the SYT8 gene, located over 300 kb away. This interaction is elevated by glucose and accompanied by increases in SYT8 expression. Inactivation of the INS promoter by promoter-targeting siRNA reduces SYT8 gene expression. SYT8-INS interaction and SYT8 transcription are attenuated by CTCF depletion. Furthermore, SYT8 knockdown decreases insulin secretion in islets. These results reveal a non-redundant role for SYT8 in insulin secretion and indicate that the INS promoter acts from a distance to stimulate SYT8 transcription. This suggests a function for the INS promoter in coordinating insulin transcription and secretion through long-range regulation of SYT8 expression in human islets.
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404
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Pollock CB, Yin Y, Yuan H, Zeng X, King S, Li X, Kopelovich L, Albanese C, Glazer RI. PPARδ activation acts cooperatively with 3-phosphoinositide-dependent protein kinase-1 to enhance mammary tumorigenesis. PLoS One 2011; 6:e16215. [PMID: 21297860 PMCID: PMC3020974 DOI: 10.1371/journal.pone.0016215] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Accepted: 12/10/2010] [Indexed: 11/18/2022] Open
Abstract
Peroxisome proliferator-activated receptorδ (PPARδ) is a transcription factor that is associated with metabolic gene regulation and inflammation. It has been implicated in tumor promotion and in the regulation of 3-phosphoinositide-dependent kinase-1 (PDK1). PDK1 is a key regulator of the AGC protein kinase family, which includes the proto-oncogene AKT/PKB implicated in several malignancies, including breast cancer. To assess the role of PDK1 in mammary tumorigenesis and its interaction with PPARδ, transgenic mice were generated in which PDK1 was expressed in mammary epithelium under the control of the MMTV enhancer/promoter region. Transgene expression increased pT308AKT and pS9GSK3β, but did not alter phosphorylation of mTOR, 4EBP1, ribosomal protein S6 and PKCα. The transgenic mammary gland also expressed higher levels of PPARδ and a gene expression profile resembling wild-type mice maintained on a diet containing the PPARδ agonist, GW501516. Both wild-type and transgenic mice treated with GW501516 exhibited accelerated rates of tumor formation that were more pronounced in transgenic animals. GW501516 treatment was accompanied by a distinct metabolic gene expression and metabolomic signature that was not present in untreated animals. GW501516-treated transgenic mice expressed higher levels of fatty acid and phospholipid metabolites than treated wild-type mice, suggesting the involvement of PDK1 in enhancing PPARδ-driven energy metabolism. These results reveal that PPARδ activation elicits a distinct metabolic and metabolomic profile in tumors that is in part related to PDK1 and AKT signaling.
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Affiliation(s)
- Claire B. Pollock
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Yuzhi Yin
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Hongyan Yuan
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Xiao Zeng
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Sruthi King
- Department of Pharmacology, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Xin Li
- Department of Biostatistics, Bioinformatics and Biomathematics, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Levy Kopelovich
- Chemoprevention Agent Development and Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland, United States of America
| | - Chris Albanese
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Robert I. Glazer
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, D.C., United States of America
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405
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Ijichi N, Shigekawa T, Ikeda K, Horie-Inoue K, Fujimura T, Tsuda H, Osaki A, Saeki T, Inoue S. Estrogen-related receptor γ modulates cell proliferation and estrogen signaling in breast cancer. J Steroid Biochem Mol Biol 2011; 123:1-7. [PMID: 20883782 DOI: 10.1016/j.jsbmb.2010.09.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 09/15/2010] [Accepted: 09/19/2010] [Indexed: 12/01/2022]
Abstract
Breast cancer is primarily a hormone-dependent tumor that can be regulated by status of steroid hormones including estrogen and progesterone. Estrogen-related receptors (ERRs) are orphan nuclear receptors most closely related to estrogen receptor (ER) and much attention has been recently paid to the functions of ERRs in breast cancer in terms of the interactions with ER. In the present study, we investigated the expression of ERRγ in human invasive breast cancers by immunohistochemical analysis (n=110) obtained by radical mastectomy. Nuclear immunoreactivity of ERRγ was detected in 87 cases (79%) and tended to correlate with the lymph node status. No significant associations were observed with other clinicopathological characteristics, including the expression levels of both estrogen and progesterone receptors. In MCF-7 breast cancer cells, we demonstrated that ERRγ mRNA was up-regulated dose-dependently by estrogen, and that this up-regulation of ERRγ mRNA by estrogen was abolished by ICI 182,780 treatment. We also demonstrated that exogenously transfected ERRγ increased MCF-7 cell proliferation. Furthermore, ERRγ enhanced estrogen response element (ERE)-driven transcription in MCF-7 cells. In 293T cells, ERRγ could also stimulate ERE-mediated transcription with or without ERα. These results suggest that ERRγ plays an important role as a modulator of estrogen signaling in breast cancer cells.
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Affiliation(s)
- Nobuhiro Ijichi
- Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama, Japan
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406
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Ahmad N, Kumar R. Steroid hormone receptors in cancer development: a target for cancer therapeutics. Cancer Lett 2011; 300:1-9. [PMID: 20926181 DOI: 10.1016/j.canlet.2010.09.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 09/05/2010] [Accepted: 09/08/2010] [Indexed: 01/02/2023]
Abstract
The steroid hormone receptors (SHRs) are ligand-dependent intracellular transcription factors that are known to influence the development and growth of many human cancers. SHRs pass signals from a steroid/hormone to the target genes by interacting with specific response element DNA sequences and various coregulatory proteins that consists of activators and/or corepressors. Disruptions in physiological functions of SHRs leads to several types of malignancies such as breast cancer, leukemia and lymphoma, prostate cancer, ovarian cancer, and lung cancer among others. Steroids/hormones/SHRs and their coregulators have opened up a unique window for novel steroid-based targeted therapies for cancer. Thus, dysregulation of SHR signaling in cancers compared with normal tissues can be exploited to target drugs that prevent and treat human cancers. In recent years, hormonal therapy has made a major contribution to the treatment of several cancers including reduced recurrence rates and longer survival rates. Development of various steroid receptor modulators and their potential therapeutic efficacies has provided us a great opportunity to effectively manage diseases like cancer in future. In this review article, we have summarized up-to-date knowledge of the role of SHRs in the development and progression of cancers, and potential endocrine-based therapeutic approaches to tackle these diseases.
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Affiliation(s)
- Nihal Ahmad
- Department of Dermatology, University of Wisconsin, Madison, WI, USA
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407
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Deblois G, Chahrour G, Perry MC, Sylvain-Drolet G, Muller WJ, Giguère V. Transcriptional control of the ERBB2 amplicon by ERRalpha and PGC-1beta promotes mammary gland tumorigenesis. Cancer Res 2010; 70:10277-87. [PMID: 20961995 DOI: 10.1158/0008-5472.can-10-2840] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Overexpression of ERBB2 and its neighboring genes on chromosome 17 occurs in approximately 25% of breast tumors and is associated with poor prognosis. While amplification of the 17q12-21 chromosomal region often correlates with an increase in the transcriptional rates of the locus, the molecular mechanisms and the factors involved in the coordinated expression of genes residing within the ERBB2 amplicon remain largely unknown. Here we demonstrate that estrogen-related receptor α (ERRα, NR3B1) and its coregulator PGC-1β are key effectors in this process. Using a mouse model of ERBB2-initiated mammary tumorigenesis, we first show that ablation of ERRα significantly delays ERBB2-induced tumor development and lowers the levels of amplicon transcripts. Chromosome 17q-wide binding site location analyses in human breast cancer cells show preferential recruitment of ERRα to DNA segments associated with the ERBB2 amplicon. Furthermore, ERRα directs the co-recruitment of the coactivator PGC-1β to segments in the 17q12 region and the recruitment of RNA polymerase II to the promoters of the ERBB2 and coamplified genes. ERRα and PGC-1β also participate in the de-repression of ERBB2 expression through competitive genomic cross-talk with estrogen receptor α (ERα) and, as a consequence, influence tamoxifen sensitivity in breast cancer cells. Taken together, our results suggest that ERRα and PGC-1β are key players in the etiology of malignant breast cancer by coordinating the transcriptional regulation of genes located in the 17q12 region, a process that also involves interference with the repressive function of ERα on ERBB2 expression.
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MESH Headings
- Animals
- Breast Neoplasms/genetics
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Line, Tumor
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Chromosomes, Human, Pair 17
- Drug Resistance, Neoplasm
- Female
- GRB7 Adaptor Protein/genetics
- Gene Amplification
- Gene Expression Regulation, Neoplastic
- Genes, erbB-2
- Humans
- Mammary Neoplasms, Experimental/genetics
- Mammary Neoplasms, Experimental/metabolism
- Mice
- Mice, Transgenic
- RNA-Binding Proteins
- Receptor, ErbB-2/biosynthesis
- Receptor, ErbB-2/genetics
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Tamoxifen/pharmacology
- ERRalpha Estrogen-Related Receptor
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Affiliation(s)
- Geneviève Deblois
- Goodman Cancer Research Centre, McGill University, Montréal, Québec, Canada
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408
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Abstract
Although it is well established that physical activity increases mitochondrial content in muscle, the molecular mechanisms underlying this process have only recently been elucidated. Mitochondrial dysfunction is an important component of different diseases associated with aging, such as Type 2 diabetes and Alzheimer's disease. PGC-1alpha (peroxisome-proliferator-activated receptor gamma co-activator-1alpha) is a co-transcriptional regulation factor that induces mitochondrial biogenesis by activating different transcription factors, including nuclear respiratory factor 1 and nuclear respiratory factor 2, which activate mitochondrial transcription factor A. The latter drives transcription and replication of mitochondrial DNA. PGC-1alpha itself is regulated by several different key factors involved in mitochondrial biogenesis, which will be reviewed in this chapter. Of those, AMPK (AMP-activated protein kinase) is of major importance. AMPK acts as an energy sensor of the cell and works as a key regulator of mitochondrial biogenesis. AMPK activity has been shown to decrease with age, which may contribute to decreased mitochondrial biogenesis and function with aging. Given the potentially important role of mitochondrial dysfunction in the pathogenesis of numerous diseases and in the process of aging, understanding the molecular mechanisms regulating mitochondrial biogenesis and function may provide potentially important novel therapeutic targets.
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409
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Liao X, Wang Y, Wong CW. Troglitazone induces cytotoxicity in part by promoting the degradation of peroxisome proliferator-activated receptor γ co-activator-1α protein. Br J Pharmacol 2010; 161:771-81. [PMID: 20860658 DOI: 10.1111/j.1476-5381.2010.00900.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND AND PURPOSE Troglitazone (Tro), rosiglitazone (Rosi) and pioglitazone (Pio) are anti-diabetic thiazolidinediones that function as ligands for peroxisome proliferator-activated receptor γ (PPARγ); however, Tro has been withdrawn from the market due to liver toxicity issues. Mitochondrial dysfunction induced by Tro has been suggested to be an important mechanism behind its cytotoxicity. Constitutively active nuclear hormone receptors, oestrogen-related receptor α and γ are thought to regulate mitochondrial mass and oxidative phosphorylation together with their co-activators PPARγ co-activator-1α and -1β (PGC-1α and PGC-1β). Hence, in this study, we investigated whether Tro affects the expression and activity levels of these regulators. EXPERIMENTAL APPROACH Cellular viability was measured by an ATP-based assay. Mitochondrial mass and reactive oxygen species (ROS) were quantified by two different fluorogenic probes. Apoptosis was measured by an Annexin-V-based kit. Gene expression at the levels of mRNA and protein was measured by quantitative RT-PCR and Western analysis. Over-expression of PGC-1α was mediated by an adenovirus. KEY RESULTS Tro, but not Rosi or Pio, selectively stimulated PGC-1α protein degradation. As a result, Tro reduced mitochondrial mass, and superoxide dismutases 1 and 2 expressions, but induced ROS to initiate apoptosis. Using a ubiquitin-proteasome inhibitor MG132, it was established that blocking PGC-1α degradation partially suppressed the reduction of mitochondrial mass. Importantly, over-expressing PGC-1α partially restored the Tro-suppressed mitochondrial mass and attenuated the cytotoxic effects of Tro. CONCLUSIONS AND IMPLICATIONS Collectively, these results suggest that PGC-1α degradation is an important mechanism behind the cytotoxic effects of Tro in the liver.
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Affiliation(s)
- Xuemei Liao
- Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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410
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Chao WR, Amin K, Shi Y, Hobbs P, Tanabe M, Tanga M, Jong L, Collins N, Peters R, Laderoute K, Dinh D, Yean D, Hou C, Sato B, Alt C, Sambucetti L. SR16388: a steroidal antiangiogenic agent with potent inhibitory effect on tumor growth in vivo. Angiogenesis 2010; 14:1-16. [PMID: 21104121 DOI: 10.1007/s10456-010-9191-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 10/18/2010] [Indexed: 12/15/2022]
Abstract
Angiogenesis is one of the major processes controlling growth and metastasis of tumors. Angiogenesis inhibitors have been targeted for the treatment of various cancers for more than 2 decades. We have developed a novel class of steroidal compounds aimed at blocking the angiogenic process in cancerous tissues. Our lead compound, SR16388, is a potent antiangiogenic agent with binding affinity to estrogen receptor-α (ER-α) and -β (ER-β) at the nanomolar range. This compound inhibited the proliferation of human microvascular endothelial cells (HMVEC) and various types of human cancer cells in vitro. SR16388 inhibited embryonic angiogenesis as measured in the chick chorioallantoic membrane (CAM) assay. The blood vessel density in the CAM was greatly reduced after the embryos were treated with 3 μg/CAM of SR16388 for 24 h. SR16388 at a dose of 2 μM prevented tube formation in Matrigel after HMVEC cells were treated for 8 h. In a modified Boyden chamber assay, SR16388 inhibited the migration of HMVECs by 80% at 500 nM. Using a novel in vivo Fibrin Z-chamber model, we demonstrated that SR16388 at a single daily oral dose of 3 mg/kg for 12 days significantly inhibited the granulation tissue (GT) thickness and the microvessel density of the GT as compared to control. More importantly, SR16388 down-regulated the pro-angiogenic transcription factors, hypoxia inducible factor 1α (HIF-1α) and signal transducer and activator of transcription 3 (STAT3) in non-small cell lung cancer (NSCLC) cells. Together, these effects of SR16388 can lead to the reduction of vascularization and tumor growth in vivo.
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Affiliation(s)
- Wan-Ru Chao
- Drug Discovery Department, Biosciences Division, SRI International, 333 Ravenswood Ave, Menlo Park, CA 94025, USA.
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411
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Dwyer MA, Joseph J, Wade HE, Eaton ML, Kunder RS, Kazmin D, Chang CY, McDonnell DP. WNT11 expression is induced by estrogen-related receptor alpha and beta-catenin and acts in an autocrine manner to increase cancer cell migration. Cancer Res 2010; 70:9298-308. [PMID: 20870744 PMCID: PMC2982857 DOI: 10.1158/0008-5472.can-10-0226] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Elevated expression of the orphan nuclear receptor estrogen-related receptor α (ERRα) has been associated with a negative outcome in several cancers, although the mechanism(s) by which this receptor influences the pathophysiology of this disease and how its activity is regulated remain unknown. Using a chemical biology approach, it was determined that compounds, previously shown to inhibit canonical Wnt signaling, also inhibited the transcriptional activity of ERRα. The significance of this association was revealed in a series of biochemical and genetic experiments that show that (a) ERRα, β-catenin (β-cat), and lymphoid enhancer-binding factor-1 form macromolecular complexes in cells, (b) ERRα transcriptional activity is enhanced by β-cat expression and vice versa, and (c) there is a high level of overlap among genes previously shown to be regulated by ERRα or β-cat. Furthermore, silencing of ERRα and β-cat expression individually or together dramatically reduced the migratory capacity of breast, prostate, and colon cancer cells in vitro. This increased migration could be attributed to the ERRα/β-cat-dependent induction of WNT11. Specifically, using (a) conditioned medium from cells overexpressing recombinant WNT11 or (b) WNT11 neutralizing antibodies, we were able to show that this protein was the key mediator of the promigratory activities of ERRα/β-cat. Together, these data provide evidence for an autocrine regulatory loop involving transcriptional upregulation of WNT11 by ERRα and β-cat that influences the migratory capacity of cancer cells.
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Affiliation(s)
- Mary A. Dwyer
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - James Joseph
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Hilary E. Wade
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Matthew L. Eaton
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Rebecca S. Kunder
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Dmitri Kazmin
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Ching-yi Chang
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
| | - Donald P. McDonnell
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC
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412
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Abstract
The beating heart requires a constant flux of ATP to maintain contractile function, and there is increasing evidence that energetic defects contribute to the development of heart failure. The last 10 years have seen a resurgent interest in cardiac intermediary metabolism and a dramatic increase in our understanding of transcriptional networks that regulate cardiac energetics. The PPAR-γ coactivator (PGC)-1 family of proteins plays a central role in these pathways. The mechanisms by which PGC-1 proteins regulate transcriptional networks and are regulated by physiological cues, as well as the roles they play in cardiac development and disease, are reviewed here.
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Affiliation(s)
- Glenn C Rowe
- Beth Israel Deaconess Medical Center, Boston, MA, USA
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413
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miR-378(∗) mediates metabolic shift in breast cancer cells via the PGC-1β/ERRγ transcriptional pathway. Cell Metab 2010; 12:352-361. [PMID: 20889127 DOI: 10.1016/j.cmet.2010.09.002] [Citation(s) in RCA: 221] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Revised: 04/07/2010] [Accepted: 06/23/2010] [Indexed: 01/09/2023]
Abstract
Cancer cell metabolism is often characterized by a shift from an oxidative to a glycolytic bioenergetics pathway, a phenomenon known as the Warburg effect. miR-378(∗) is embedded within PPARGC1b which encodes PGC-1β, a transcriptional regulator of oxidative energy metabolism. Here we show that miR-378(∗) expression is regulated by ERBB2 and induces a metabolic shift in breast cancer cells. miR-378(∗) performs this function by inhibiting the expression of two PGC-1β partners, ERRγ and GABPA, leading to a reduction in tricarboxylic acid cycle gene expression and oxygen consumption as well as an increase in lactate production and in cell proliferation. In situ hybridization experiments show that miR-378(∗) expression correlates with progression of human breast cancer. These results identify miR-378(∗) as a molecular switch involved in the orchestration of the Warburg effect in breast cancer cells via interference with a well-integrated bioenergetics transcriptional pathway.
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414
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Menconi MJ, Arany ZP, Alamdari N, Aversa Z, Gonnella P, O'Neal P, Smith IJ, Tizio S, Hasselgren PO. Sepsis and glucocorticoids downregulate the expression of the nuclear cofactor PGC-1beta in skeletal muscle. Am J Physiol Endocrinol Metab 2010; 299:E533-43. [PMID: 20647557 PMCID: PMC2957862 DOI: 10.1152/ajpendo.00596.2009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Muscle wasting during sepsis is at least in part regulated by glucocorticoids and is associated with increased transcription of genes encoding the ubiquitin ligases atrogin-1 and muscle-specific RING-finger protein-1 (MuRF1). Recent studies suggest that muscle atrophy caused by denervation is associated with reduced expression of the nuclear cofactor peroxisome proliferator-activated receptor-γ coactivator (PGC)-1β and that PGC-1β may be a repressor of the atrogin-1 and MuRF1 genes. The influence of other muscle-wasting conditions on the expression of PGC-1β is not known. We tested the influence of sepsis and glucocorticoids on PGC-1β and examined the potential link between downregulated PGC-1β expression and upregulated atrogin-1 and MuRF1 expression in skeletal muscle. Sepsis in rats and mice and treatment with dexamethasone resulted in downregulated expression of PGC-1β and increased expression of atrogin-1 and MuRF1 in the fast-twitch extensor digitorum longus muscle, with less pronounced changes in the slow-twitch soleus muscle. In additional experiments, adenoviral gene transfer of PGC-1β into cultured C2C12 myotubes resulted in a dose-dependent decrease in atrogin-1 and MuRF1 mRNA levels. Treatment of cultured C2C12 myotubes with dexamethasone or PGC-1β small interfering RNA (siRNA) resulted in downregulated PGC-1β expression and increased protein degradation. Taken together, our results suggest that sepsis- and glucocorticoid-induced muscle wasting may, at least in part, be regulated by decreased expression of the nuclear cofactor PGC-1β.
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Affiliation(s)
- Michael J Menconi
- Departmentof Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 2215, USA
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415
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Bombail V, Gibson DA, Collins F, MacPherson S, Critchley HOD, Saunders PTK. A Role for the orphan nuclear receptor estrogen-related receptor alpha in endometrial stromal cell decidualization and expression of genes implicated in energy metabolism. J Clin Endocrinol Metab 2010; 95:E224-8. [PMID: 20668045 PMCID: PMC3050102 DOI: 10.1210/jc.2010-0154] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 06/28/2010] [Indexed: 01/05/2023]
Abstract
CONTEXT Differentiation (decidualization) of endometrial stromal cells (ESC) is an essential prerequisite for successful implantation and establishment of pregnancy. OBJECTIVE The aim was to determine whether the orphan nuclear receptor estrogen-related receptor α (ERRα, NR3B1), and its target genes, medium chain specific acyl-CoA dehydrogenase (MCAD, ACADM), pyruvate dehydrogenase kinase 4 (PDK4), and phosphoenolpyruvate carboxykinase 2 (PEPCK, PCK2), play a role in the decidualization process. SETTING We conducted the study at a University Research Institute. PATIENTS AND METHODS Endometrial tissues were collected from women with regular menstrual cycles; tissues were used for recovery of primary ESC or RNA extraction or were fixed for immunohistochemistry. Primary ESC were decidualized in vitro; some cells were treated with XCT790 (ERRα inverse agonist). RESULTS Decidualization of ESC in vitro was associated with a significant increase in expression of transcripts encoding ERRα and its coactivator peroxisome proliferator-activated receptor γ coactivator-1 α. Expression of ERRα target genes was altered with increased expression of MCAD and PDK4 and reduced expression of PEPCK. Incubation of decidualized ESC with XCT790 reduced expression of ERRα and markers of decidualization such as IGFBP-1. CONCLUSION Increased expression of ERRα may play a role in altering the bioenergetics of decidualized ESC in preparation for implantation of the embryo and successful establishment of early pregnancy.
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Affiliation(s)
- Vincent Bombail
- Medical Research Council Human Reproductive Sciences Unit, University of Edinburgh Centre for Reproductive Biology, The Queen's Medical Research Institute, Edinburgh, United Kingdom
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416
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Gallet M, Vanacker JM. ERR receptors as potential targets in osteoporosis. Trends Endocrinol Metab 2010; 21:637-41. [PMID: 20674386 DOI: 10.1016/j.tem.2010.06.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 06/18/2010] [Accepted: 06/28/2010] [Indexed: 01/12/2023]
Abstract
The bone fragility and increased fracture risk associated with osteoporosis in post-menopausal women is a major public health concern. Current treatments for osteoporosis relying on hormone replacement therapies are suspected to have an association with increased breast cancer risk, highlighting the need for identifying new potential targets in bone. Recent data suggest that the estrogen-related receptor (ERR)α, an orphan nuclear receptor, represses osteoblast differentiation, and that its deletion in knockout mouse models results in increased mineral density. Furthermore, modulation of ERRα activity reduces proliferation and tumorigenesis of breast cancer cells. These results indicated that inhibition of ERRα might provide a treatment for osteoporosis without displaying adverse effects in breast cancer. This review focuses on the role of the ERR receptors, and in particular ERRα, in the differentiation of bone precursor cells and its consequences on bone homeostasis, and discusses the possible grounds for the discrepancies reported in the literature.
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Affiliation(s)
- Marlène Gallet
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France
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417
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Duellman SJ, Calaoagan JM, Sato BG, Fine R, Klebansky B, Chao WR, Hobbs P, Collins N, Sambucetti L, Laderoute KR. A novel steroidal inhibitor of estrogen-related receptor alpha (ERR alpha). Biochem Pharmacol 2010; 80:819-26. [PMID: 20513360 PMCID: PMC2918268 DOI: 10.1016/j.bcp.2010.05.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 05/20/2010] [Accepted: 05/21/2010] [Indexed: 01/15/2023]
Abstract
The orphan nuclear receptor estrogen-related receptor alpha (ERRalpha) has been implicated in the development of various human malignancies, including breast, prostate, ovary, and colon cancer. ERRalpha, bound to a co-activator protein (e.g., peroxisome proliferator receptor gamma co-activator-1alpha, PGC-1alpha), regulates cellular energy metabolism by activating transcription of genes involved in various metabolic processes, such as mitochondrial genesis, oxidative phosphorylation, and fatty acid oxidation. Accumulating evidence suggests that ERRalpha is a novel target for solid tumor therapy, conceivably through effects on the regulation of tumor cell energy metabolism associated with energy stress within solid tumor microenvironments. This report describes a novel steroidal antiestrogen (SR16388) that binds selectively to ERRalpha, but not to ERRbeta or ERRgamma, as determined using a time-resolved fluorescence resonance energy transfer assay. SR16388 potently inhibits ERRalpha's transcriptional activity in reporter gene assays, and prevents endogenous PGC-1alpha and ERRalpha from being recruited to the promoters or enhancers of target genes. Representative in vivo results show that SR16388 inhibited the growth of human prostate tumor xenografts in nude mice as a single agent at 30mg/kg given once daily and 100mg/kg given once weekly. In a combination study, SR16388 (10mg/kg, once daily) and paclitaxel (7.5mg/kg, twice weekly) inhibited the growth of prostate tumor xenografts in nude mice by 61% compared to untreated xenograft tumors. SR16388 also inhibited the proliferation of diverse human tumor cell lines after a 24-h exposure to the compound. SR16388 thus has utility both as an experimental antitumor agent and as a chemical probe of ERRalpha biology.
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Affiliation(s)
- Sarah J Duellman
- Biosciences Division, SRI International, 333 Ravenswood Ave., Menlo Park, CA 94025, United States.
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418
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De Rasmo D, Signorile A, Papa F, Roca E, Papa S. cAMP/Ca2+ response element-binding protein plays a central role in the biogenesis of respiratory chain proteins in mammalian cells. IUBMB Life 2010; 62:447-52. [PMID: 20503437 DOI: 10.1002/iub.342] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
In mammalian cells, promotion of mitochondrial biogenesis by various agents involves cAMP and Ca(2+)-mediated signal transduction pathways. Recruitment of these pathways results in phosphorylation by cAMP and Ca(2+)-dependent protein kinases of cAMP/Ca(2+) response element-binding protein (CREB). Phosphorylation of CREB, bound to transcriptional complexes of target genes, activates a down-stream cascade of transcriptional complexes, which involve in sequence, the nuclear factors TORCs, PGC-1, NRF1 and NRF2, and the mitochondrial factor mitochondrial transcriptional factor A. CREB also binds directly to the D-loop of mitochondrial DNA and activates its expression. Activation of this network of transcriptional complexes results in concerted promotion of the expression of nuclear and mitochondrial genes encoding subunits of oxidative phosphorylation complexes.
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Affiliation(s)
- Domenico De Rasmo
- Department of Medical Biochemistry, Biology and Physics, University of Bari, P.zza G. Cesare, 70124 Bari, Italy
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419
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Mason EF, Rathmell JC. Cell metabolism: an essential link between cell growth and apoptosis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1813:645-54. [PMID: 20816705 DOI: 10.1016/j.bbamcr.2010.08.011] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 08/20/2010] [Accepted: 08/24/2010] [Indexed: 12/12/2022]
Abstract
Growth factor-stimulated or cancerous cells require sufficient nutrients to meet the metabolic demands of cell growth and division. If nutrients are insufficient, metabolic checkpoints are triggered that lead to cell cycle arrest and the activation of the intrinsic apoptotic cascade through a process dependent on the Bcl-2 family of proteins. Given the connections between metabolism and apoptosis, the notion of targeting metabolism to induce cell death in cancer cells has recently garnered much attention. However, the signaling pathways by which metabolic stresses induce apoptosis have not as of yet been fully elucidated. Thus, the best approach to this promising therapeutic avenue remains unclear. This review will discuss the intricate links between metabolism, growth, and intrinsic apoptosis and will consider ways in which manipulation of metabolism might be exploited to promote apoptotic cell death in cancer cells. This article is part of a Special Issue entitled Mitochondria: the deadly organelle.
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Affiliation(s)
- Emily F Mason
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
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420
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Riggins RB, Mazzotta MM, Maniya OZ, Clarke R. Orphan nuclear receptors in breast cancer pathogenesis and therapeutic response. Endocr Relat Cancer 2010; 17:R213-31. [PMID: 20576803 PMCID: PMC3518023 DOI: 10.1677/erc-10-0058] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nuclear receptors comprise a large family of highly conserved transcription factors that regulate many key processes in normal and neoplastic tissues. Most nuclear receptors share a common, highly conserved domain structure that includes a carboxy-terminal ligand-binding domain. However, a subgroup of this gene family is known as the orphan nuclear receptors because to date there are no known natural ligands that regulate their activity. Many of the 25 nuclear receptors classified as orphan play critical roles in embryonic development, metabolism, and the regulation of circadian rhythm. Here, we review the emerging role(s) of orphan nuclear receptors in breast cancer, with a particular focus on two of the estrogen-related receptors (ERRalpha and ERRgamma) and several others implicated in clinical outcome and response or resistance to cytotoxic or endocrine therapies, including the chicken ovalbumin upstream promoter transcription factors, nerve growth factor-induced B, DAX-1, liver receptor homolog-1, and retinoic acid-related orphan receptor alpha. We also propose that a clearer understanding of the function of orphan nuclear receptors in mammary gland development and normal mammary tissues could significantly improve our ability to diagnose, treat, and prevent breast cancer.
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Affiliation(s)
- Rebecca B. Riggins
- Lombardi Comprehensive Cancer Center and Department of Oncology, Georgetown University School of Medicine, 3970 Reservoir Road NW, Washington, DC 20057, USA
| | - Mary M. Mazzotta
- Lombardi Comprehensive Cancer Center and Department of Oncology, Georgetown University School of Medicine, 3970 Reservoir Road NW, Washington, DC 20057, USA
| | - Omar Z. Maniya
- Lombardi Comprehensive Cancer Center and Department of Oncology, Georgetown University School of Medicine, 3970 Reservoir Road NW, Washington, DC 20057, USA
| | - Robert Clarke
- Lombardi Comprehensive Cancer Center and Department of Oncology, Georgetown University School of Medicine, 3970 Reservoir Road NW, Washington, DC 20057, USA
- Department of Physiology and Biophysics, Georgetown University School of Medicine, 3970 Reservoir Road NW, Washington, DC 20057, USA
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421
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Segrè AV, Groop L, Mootha VK, Daly MJ, Altshuler D. Common inherited variation in mitochondrial genes is not enriched for associations with type 2 diabetes or related glycemic traits. PLoS Genet 2010; 6. [PMID: 20714348 PMCID: PMC2920848 DOI: 10.1371/journal.pgen.1001058] [Citation(s) in RCA: 395] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 07/08/2010] [Indexed: 01/02/2023] Open
Abstract
Mitochondrial dysfunction has been observed in skeletal muscle of people with diabetes and insulin-resistant individuals. Furthermore, inherited mutations in mitochondrial DNA can cause a rare form of diabetes. However, it is unclear whether mitochondrial dysfunction is a primary cause of the common form of diabetes. To date, common genetic variants robustly associated with type 2 diabetes (T2D) are not known to affect mitochondrial function. One possibility is that multiple mitochondrial genes contain modest genetic effects that collectively influence T2D risk. To test this hypothesis we developed a method named Meta-Analysis Gene-set Enrichment of variaNT Associations (MAGENTA; http://www.broadinstitute.org/mpg/magenta). MAGENTA, in analogy to Gene Set Enrichment Analysis, tests whether sets of functionally related genes are enriched for associations with a polygenic disease or trait. MAGENTA was specifically designed to exploit the statistical power of large genome-wide association (GWA) study meta-analyses whose individual genotypes are not available. This is achieved by combining variant association p-values into gene scores and then correcting for confounders, such as gene size, variant number, and linkage disequilibrium properties. Using simulations, we determined the range of parameters for which MAGENTA can detect associations likely missed by single-marker analysis. We verified MAGENTA's performance on empirical data by identifying known relevant pathways in lipid and lipoprotein GWA meta-analyses. We then tested our mitochondrial hypothesis by applying MAGENTA to three gene sets: nuclear regulators of mitochondrial genes, oxidative phosphorylation genes, and ∼1,000 nuclear-encoded mitochondrial genes. The analysis was performed using the most recent T2D GWA meta-analysis of 47,117 people and meta-analyses of seven diabetes-related glycemic traits (up to 46,186 non-diabetic individuals). This well-powered analysis found no significant enrichment of associations to T2D or any of the glycemic traits in any of the gene sets tested. These results suggest that common variants affecting nuclear-encoded mitochondrial genes have at most a small genetic contribution to T2D susceptibility. Mitochondria play a crucial role in metabolic homeostasis, and alteration of mitochondrial function is a hallmark of diabetes. While mitochondrial activity is reduced in people with diabetes, it is unclear whether mitochondrial dysfunction is a cause or effect of type 2 diabetes. Genome-wide association studies for type 2 diabetes have explained ≈10% of the heritability of the disease, but none of the loci are known to affect mitochondrial activity. It is possible though that a mitochondrial contribution is hidden in the remaining 90%. Hence, we tested the hypothesis that multiple mitochondria-related genes encoded in the nucleus, each having a weak effect (hard to detect individually), can collectively influence type 2 diabetes. To address this, we developed a computational method (MAGENTA) that allowed us to adequately analyze large collective datasets of human genetic variation obtained from collaborative studies of type 2 diabetes and related glycemic traits. Despite the increased sensitivity of MAGENTA compared to single-DNA variant analysis, we found no support for a causal relationship between mitochondrial dysfunction and type 2 diabetes. These results may help steer future efforts in understanding the pathogenesis of the disease. MAGENTA is broadly applicable to testing associations between other biological pathways and common diseases or traits.
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Affiliation(s)
- Ayellet V. Segrè
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- * E-mail: (DA); (AVS)
| | | | | | - Leif Groop
- Department of Clinical Sciences, Diabetes and Endocrinology Research Unit, University Hospital Malmö, Lund University, Malmö, Sweden
| | - Vamsi K. Mootha
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Mark J. Daly
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - David Altshuler
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
- Diabetes Unit, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (DA); (AVS)
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422
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Ranhotra HS. The estrogen-related receptor alpha: the oldest, yet an energetic orphan with robust biological functions. J Recept Signal Transduct Res 2010; 30:193-205. [PMID: 20497091 DOI: 10.3109/10799893.2010.487493] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The estrogen-related receptor alpha (ERRalpha) is an orphan nuclear receptor (ONR) that by binding to DNA sites controls gene expression in association with coactivators and corepressors. ERRalpha was the first ONR to be identified; however, its natural endogenous ligand(s) is still unknown. ERRalpha by acting as a transcription factor has been shown to regulate a large array of genes, thereby controlling numerous metabolic pathways and other biological functions in animals. Of late, the expression of ERRalpha has been detected in several tissues, including those with high metabolic activities and energy demand. Presently, the control of energy balance by ERRalpha seems to be its prime role. The nonavailability of endogenous ligand for ERRalpha has not impeded the study of its functions. In fact, most of the present knowledge of the biological roles of ERRalpha has evolved from in-depth biochemical, overexpression, genomic, including functional genomics studies, and also through the generation of intact ERRalpha knockout (null) mice. Interestingly, over the past few years, growing evidence suggests interplay between ERRalpha and various human metabolic diseases such as diabetes, obesity, and heart disease. Also, there are strong indications of the involvement of ERRalpha in cancer initiation and progression. Interestingly, this makes ERRalpha a suitable, direct target for pharmacological intervention in treating such diseases. This review focuses on the overall developments and recent advances in understanding the role of ERRalpha in metabolism and other biological functions, including its role in human diseases.
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Affiliation(s)
- Harmit S Ranhotra
- Orphan Receptor Laboratory, Department of Biochemistry, St. Edmund's College, Shillong, India.
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423
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Cantó C, Auwerx J. AMP-activated protein kinase and its downstream transcriptional pathways. Cell Mol Life Sci 2010; 67:3407-23. [PMID: 20640476 DOI: 10.1007/s00018-010-0454-z] [Citation(s) in RCA: 292] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Accepted: 07/01/2010] [Indexed: 12/19/2022]
Abstract
The AMP-activated protein kinase (AMPK) is a key regulator of catabolic versus anabolic processes. Its properties as an energy sensor allow it to couple the energy status of the cell to the metabolic environment. These adaptations not only take place through the acute modulation of key metabolic enzymes via direct phosphorylation, but also through a slower transcriptional adaptative response. The question of how AMPK regulates the expression of a number of gene sets, such as those related to mitochondrial biogenesis, energy production and oxidative protection, is only beginning to be elucidated, and still many questions remain to be answered. In this review we will try to integrate our current knowledge on how AMPK regulates transcription in muscle and liver, which will serve as examples to illustrate the major advances in the field and the key challenges ahead.
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Affiliation(s)
- Carles Cantó
- Laboratory of Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne (EPFL), SV-IBI, Building AI, Station 15, Lausanne, Switzerland
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424
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Wang Y, Fang F, Wong CW. Troglitazone is an estrogen-related receptor alpha and gamma inverse agonist. Biochem Pharmacol 2010; 80:80-5. [PMID: 20298676 DOI: 10.1016/j.bcp.2010.03.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 03/07/2010] [Accepted: 03/09/2010] [Indexed: 01/16/2023]
Abstract
As a ligand for peroxisome proliferators-activated receptor gamma (PPAR gamma), troglitazone inhibits cell growth by mechanisms besides activating PPAR gamma. In this study, we found that troglitazone interfered with the interactions between estrogen-related receptor alpha and gamma (ERR alpha and ERR gamma) and their coactivator PPAR gamma coactivator-1 alpha (PGC-1 alpha) functioning as an inverse agonist. Additionally, troglitazone suppressed the expressions of PGC-1 alpha and its related member PGC-1 beta which are key regulators of mitochondrial function. Consequently, troglitazone reduced mitochondrial mass and suppressed the expressions of superoxide dismutases to elevate reactive oxygen species (ROS) production. The increase in ROS in turn induced the expression of cell cycle inhibitor p21(WAF1). We therefore propose that ERR alpha and ERR gamma are alternative targets of troglitazone important for mediating its growth suppressive effect.
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Affiliation(s)
- Yanfei Wang
- Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Science City, Guangzhou 510663, China
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425
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Wilson BJ, Tremblay AM, Deblois G, Sylvain-Drolet G, Giguère V. An acetylation switch modulates the transcriptional activity of estrogen-related receptor alpha. Mol Endocrinol 2010; 24:1349-58. [PMID: 20484414 PMCID: PMC5417470 DOI: 10.1210/me.2009-0441] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Accepted: 04/15/2010] [Indexed: 12/23/2022] Open
Abstract
Posttranslational modifications are instrumental to achieve gene- and tissue-specific regulatory outcomes by transcription factors. Nuclear receptors are dynamically modulated by several types of posttranslational modifications including phosphorylation, methylation, acetylation, ubiquitination, and sumoylation. The estrogen-related receptor alpha (ERRalpha, NR3B1) is phosphorylated on multiple sites, and sumoylated in the amino-terminal region in a phosphorylation-dependent manner. Here we demonstrate that ERRalpha interacts with and is acetylated by p300 coactivator associated factor (PCAF) in vitro and in mouse liver. Purified PCAF acetylated the DNA-binding domain of ERRalpha on four highly-conserved lysines. In addition, coexpression of PCAF reduced the transcriptional activity of ERRalpha and, reciprocally, a deacetylase screen identified histone deacetylase 8 (HDAC8) and sirtuin 1 homolog (Sirt1) as independent enhancers of ERRalpha transcriptional function. HDAC8 and Sirt1 were also demonstrated to interact directly with ERRalpha in vivo and to deacetylate and increase the DNA binding affinity of ERRalpha in vitro. The removal of PCAF increases the DNA binding of ERRalpha in vivo, whereas the removal of Sirt1 and HDAC8 decreases it as assessed by chromatin immunoprecipitation assay. Altogether, our results show that ERRalpha is an acetylated protein and imply the existence of a dynamic acetylation/deacetylation switch involved in the control of ERRalpha transcriptional activity.
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Affiliation(s)
- Brian J Wilson
- Rosalind and Morris Goodman Cancer Research Centre, Montréal, Québec, Canada H3A1A3
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426
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Statins enhance peroxisome proliferator-activated receptor gamma coactivator-1alpha activity to regulate energy metabolism. J Mol Med (Berl) 2010; 88:309-17. [PMID: 19915805 DOI: 10.1007/s00109-009-0561-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 10/28/2009] [Accepted: 11/03/2009] [Indexed: 01/26/2023]
Abstract
Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) serves as an inducible coactivator for a number of transcription factors to control energy metabolism. Insulin signaling through Akt kinase has been demonstrated to phosphorylate PGC-1alpha at serine 571 and downregulate its activity in the liver. Statins are 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors that reduce cholesterol synthesis in the liver. In this study, we found that statins reduced the active form of Akt and enhanced PGC-1alpha activity. Specifically, statins failed to activate an S571A mutant of PGC-1alpha. The activation of PGC-1alpha by statins selectively enhanced the expression of energy metabolizing enzymes and regulators including peroxisome proliferator-activated receptor alpha, acyl-CoA oxidase, carnitine palmitoyl transferase-1A, and pyruvate dehydrogenase kinase 4. Importantly, a constitutively active form of Akt partially reduced the statin-enhanced gene expression. Our study thus provides a plausible mechanistic explanation for the hypolipidemic effect of statin through elevating the rate of beta-oxidation and mitochondrial Kreb's cycle capacity to enhance fatty acid utilization while reducing the rate of glycolysis.
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427
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Matsuyama R, Takada I, Yokoyama A, Fujiyma-Nakamura S, Tsuji N, Kitagawa H, Fujiki R, Kim M, Kouzu-Fujita M, Yano T, Kato S. Double PHD fingers protein DPF2 recognizes acetylated histones and suppresses the function of estrogen-related receptor alpha through histone deacetylase 1. J Biol Chem 2010; 285:18166-76. [PMID: 20400511 PMCID: PMC2881740 DOI: 10.1074/jbc.m109.077024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 04/12/2010] [Indexed: 11/06/2022] Open
Abstract
Estrogen-related receptor alpha (ERRalpha) is a member of the nuclear receptor superfamily and regulates many physiological functions, including mitochondrial biogenesis and lipid metabolism. ERRalpha enhances the transactivation function without endogenous ligand by associating with coactivators such as peroxisome proliferator-activated receptor gamma coactivator 1 alpha and beta (PGC-1alpha and -beta) and members of the steroid receptor coactivator family. However, the molecular mechanism by which the transactivation function of ERRalpha is converted from a repressive state to an active state is poorly understood. Here we used biochemical purification techniques to identify ERRalpha-associated proteins in HeLa cells stably expressing ERRalpha. Interestingly, we found that double PHD fingers protein DPF2/BAF45d suppressed PGC-1alpha-dependent transactivation of ERRalpha by recognizing acetylated histone H3 and associating with HDAC1. DPF2 directly bound to ERRalpha and suppressed the transactivation function of nuclear receptors such as androgen receptor. DPF2 was recruited to ERR target gene promoters in myoblast cells, and knockdown of DPF2 derepressed the level of mRNA expressed by target genes of ERRalpha. These results show that DPF2 acts as a nuclear receptor-selective co-repressor for ERRalpha by associating with both acetylated histone H3 and HDAC1.
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Affiliation(s)
- Reiko Matsuyama
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
- the Department of Obstetrics and Gynecology, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan, and
| | - Ichiro Takada
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Atsushi Yokoyama
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
- ERATO, Japan Science and Technology, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| | - Sally Fujiyma-Nakamura
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
- ERATO, Japan Science and Technology, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| | - Naoya Tsuji
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Hirochika Kitagawa
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Ryoji Fujiki
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Misun Kim
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Madoka Kouzu-Fujita
- the Department of Obstetrics and Gynecology, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan, and
| | - Tetsu Yano
- the Department of Obstetrics and Gynecology, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan, and
| | - Shigeaki Kato
- From the Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-0032, Japan
- ERATO, Japan Science and Technology, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
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428
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The orphan nuclear hormone receptor ERRbeta controls rod photoreceptor survival. Proc Natl Acad Sci U S A 2010; 107:11579-84. [PMID: 20534447 DOI: 10.1073/pnas.1000102107] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Mutation of rod photoreceptor-enriched transcription factors is a major cause of inherited blindness. We identified the orphan nuclear hormone receptor estrogen-related receptor beta (ERRbeta) as selectively expressed in rod photoreceptors. Overexpression of ERRbeta induces expression of rod-specific genes in retinas of wild-type as well as Nrl(-/-) mice, which lack rod photoreceptors. Mutation of ERRbeta results in dysfunction and degeneration of rods, whereas inverse agonists of ERRbeta trigger rapid rod degeneration, which is rescued by constitutively active mutants of ERRbeta. ERRbeta coordinates expression of multiple genes that are rate-limiting regulators of ATP generation and consumption in photoreceptors. Furthermore, enhancing ERRbeta activity rescues photoreceptor defects that result from loss of the photoreceptor-specific transcription factor Crx. Our findings demonstrate that ERRbeta is a critical regulator of rod photoreceptor function and survival, and suggest that ERRbeta agonists may be useful in the treatment of certain retinal dystrophies.
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429
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Abstract
Diabetes is the leading cause of end-stage renal disease in developed countries. In spite of glucose and blood pressure control, for example by use of angiotensin II receptor blockers, diabetic nephropathy still develops and progresses in affected patients and the development of additional protective therapeutic interventions is, therefore, required. Nuclear hormone receptors are transcription factors that regulate carbohydrate metabolism, lipid metabolism, the immune response, and inflammation. These receptors also modulate the development of fibrosis. As a result of their diverse biological effects, nuclear hormone receptors have become major pharmaceutical targets for the treatment of a host of diseases. The increasing prevalence of diabetic nephropathy has led intense investigation into the role that nuclear hormone receptors may have in slowing or preventing the progression of renal disease. This role of nuclear hormone receptors would be associated with improvements in metabolism, the immune response, and inflammation. Eight nuclear receptors have shown a renoprotective effect in the context of diabetic nephropathy. This Review discusses the evidence regarding the beneficial effects of the activation of these receptors in preventing the progression of diabetic nephropathy and describes how the discovery and development of compounds that modulate the activity of nuclear hormone receptors may provide potential additional therapeutic approaches in the management of diabetic nephropathy.
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430
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Rangwala SM, Wang X, Calvo JA, Lindsley L, Zhang Y, Deyneko G, Beaulieu V, Gao J, Turner G, Markovits J. Estrogen-related receptor gamma is a key regulator of muscle mitochondrial activity and oxidative capacity. J Biol Chem 2010; 285:22619-29. [PMID: 20418374 PMCID: PMC2903389 DOI: 10.1074/jbc.m110.125401] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Estrogen-related receptor γ (ERRγ) regulates the perinatal switch to oxidative metabolism in the myocardium. We wanted to understand the significance of induction of ERRγ expression in skeletal muscle by exercise. Muscle-specific VP16ERRγ transgenic mice demonstrated an increase in exercise capacity, mitochondrial enzyme activity, and enlarged mitochondria despite lower muscle weights. Furthermore, peak oxidative capacity was higher in the transgenics as compared with control littermates. In contrast, mice lacking one copy of ERRγ exhibited decreased exercise capacity and muscle mitochondrial function. Interestingly, we observed that increased ERRγ in muscle generates a gene expression profile that closely overlays that of red oxidative fiber-type muscle. We further demonstrated that a small molecule agonist of ERRβ/γ can increase mitochondrial function in mouse myotubes. Our data indicate that ERRγ plays an important role in causing a shift toward slow twitch muscle type and, concomitantly, a greater capacity for endurance exercise. Thus, the activation of this nuclear receptor provides a potential node for therapeutic intervention for diseases such as obesity, which is associated with reduced oxidative metabolism and a lower type I fiber content in skeletal muscle.
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Affiliation(s)
- Shamina M Rangwala
- Cardiovascular and Metabolism Disease Area, Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, USA.
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431
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le Maire A, Bourguet W, Balaguer P. A structural view of nuclear hormone receptor: endocrine disruptor interactions. Cell Mol Life Sci 2010; 67:1219-37. [PMID: 20063036 PMCID: PMC11115495 DOI: 10.1007/s00018-009-0249-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Revised: 12/03/2009] [Accepted: 12/22/2009] [Indexed: 01/14/2023]
Abstract
Endocrine-disrupting chemicals (EDCs) represent a broad class of exogenous substances that cause adverse effects in the endocrine system by interfering with hormone biosynthesis, metabolism, or action. The molecular mechanisms of EDCs involve different pathways including interactions with nuclear hormone receptors (NHRs) which are primary targets of a large variety of environmental contaminants. Here, based on the crystal structures currently available in the Protein Data Bank, we review recent studies showing the many ways in which EDCs interact with NHRs and impact their signaling pathways. Like the estrogenic chemical diethylstilbestrol, some EDCs mimic the natural hormones through conserved protein-ligand contacts, while others, such as organotins, employ radically different binding mechanisms. Such structure-based knowledge, in addition to providing a better understanding of EDC activities, can be used to predict the endocrine-disrupting potential of environmental pollutants and may have applications in drug discovery.
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Affiliation(s)
- Albane le Maire
- INSERM, U554, Centre de Biochimie Structurale, 34090 Montpellier, France
- CNRS, UMR5048, Universités Montpellier 1 & 2, 34090 Montpellier, France
| | - William Bourguet
- INSERM, U554, Centre de Biochimie Structurale, 34090 Montpellier, France
- CNRS, UMR5048, Universités Montpellier 1 & 2, 34090 Montpellier, France
| | - Patrick Balaguer
- Institut de Recherche en Cancérologie de Montpellier (IRCM), 34298 Montpellier, France
- INSERM, U896, 34298 Montpellier, France
- Université Montpellier 1, 34298 Montpellier, France
- CRLC Val d’Aurelle Paul Lamarque, 34298 Montpellier, France
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432
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Charest-Marcotte A, Dufour CR, Wilson BJ, Tremblay AM, Eichner LJ, Arlow DH, Mootha VK, Giguère V. The homeobox protein Prox1 is a negative modulator of ERR{alpha}/PGC-1{alpha} bioenergetic functions. Genes Dev 2010; 24:537-42. [PMID: 20194433 PMCID: PMC2841331 DOI: 10.1101/gad.1871610] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Accepted: 01/21/2010] [Indexed: 01/20/2023]
Abstract
Estrogen-related receptor alpha (ERRalpha) and proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) play central roles in the transcriptional control of energy homeostasis, but little is known about factors regulating their activity. Here we identified the homeobox protein prospero-related homeobox 1 (Prox1) as one such factor. Prox1 interacts with ERRalpha and PGC-1alpha, occupies promoters of metabolic genes on a genome-wide scale, and inhibits the activity of the ERRalpha/PGC-1alpha complex. DNA motif analysis suggests that Prox1 interacts with the genome through tethering to ERRalpha and other factors. Importantly, ablation of Prox1 and ERRalpha have opposite effects on the respiratory capacity of liver cells, revealing an unexpected role for Prox1 in the control of energy homeostasis.
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Affiliation(s)
- Alexis Charest-Marcotte
- Goodman Cancer Centre, McGill University, Montréal, Québec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | | | - Brian J. Wilson
- Goodman Cancer Centre, McGill University, Montréal, Québec H3A 1A3, Canada
| | - Annie M. Tremblay
- Goodman Cancer Centre, McGill University, Montréal, Québec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Lillian J. Eichner
- Goodman Cancer Centre, McGill University, Montréal, Québec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Daniel H. Arlow
- Department of Systems Biology, Massachusetts General Hospital, Cambridge, Massachusetts 02142, USA
- Centre for Human Genetic Research, Massachusetts General Hospital, Cambridge, Massachusetts 02142, USA
- Broad Institute of Massachusetts Institute of Technology/Harvard, Cambridge, Massachusetts 02142, USA
| | - Vamsi K. Mootha
- Department of Systems Biology, Massachusetts General Hospital, Cambridge, Massachusetts 02142, USA
- Centre for Human Genetic Research, Massachusetts General Hospital, Cambridge, Massachusetts 02142, USA
- Broad Institute of Massachusetts Institute of Technology/Harvard, Cambridge, Massachusetts 02142, USA
| | - Vincent Giguère
- Goodman Cancer Centre, McGill University, Montréal, Québec H3A 1A3, Canada
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
- Department of Medicine, McGill University, Montréal, Québec H3G 1Y6, Canada
- Department of Oncology, McGill University, Montréal, Québec H3G 1Y6, Canada
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433
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Fujimura T, Takahashi S, Urano T, Ijichi N, Ikeda K, Kumagai J, Murata T, Takayama K, Horie-Inoue K, Ouchi Y, Muramatsu M, Homma Y, Inoue S. Differential expression of estrogen-related receptors beta and gamma (ERRbeta and ERRgamma) and their clinical significance in human prostate cancer. Cancer Sci 2010; 101:646-51. [PMID: 20128821 PMCID: PMC11158660 DOI: 10.1111/j.1349-7006.2009.01451.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Estrogen-related receptor (ERR) is a nuclear receptor that modulates the estrogen-signaling pathway. Here, we investigated the expression of both ERRbeta and ERRgamma in human prostate tissues. Using original rabbit polyclonal anti-ERRbeta and anti-ERRgamma antibodies, the expression of ERRbeta and ERRgamma was evaluated by immunohistochemical analysis of cancerous lesions (n = 107) and benign foci (n = 92), obtained by radical prostatectomy. Stained slides were evaluated for the proportion of immunoreactive cells and their staining intensity. Total immunoreactivity scores (IR scores; range, 0-8) were calculated as the sum of the proportion and intensity scores. The relationship between the clinicopathological characteristics of the patients and the expression of the three ERRs (ERRalpha, ERR beta, and ERR gamma) was evaluated. IR scores for ERRbeta and ERRgamma were significantly lower in cancerous lesions than that in benign foci (P < 0.0001, for both). Clinicopathological analyses revealed that the patients with low ERRgamma IR scores (
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Affiliation(s)
- Tetsuya Fujimura
- Department of Urology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
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434
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Gandhari MK, Frazier CR, Hartenstein JS, Cloix JF, Bernier M, Wainer IW. Identification and characterization of estrogen receptor-related receptor alpha and gamma in human glioma and astrocytoma cells. Mol Cell Endocrinol 2010; 315:314-8. [PMID: 19822186 PMCID: PMC2815036 DOI: 10.1016/j.mce.2009.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Accepted: 10/02/2009] [Indexed: 01/15/2023]
Abstract
The purpose of this study was to examine expression and function of estrogen receptor-related receptors (ERRs) in human glioma and astrocytoma cell lines. These estrogen receptor-negative cell lines expressed ERRalpha and ERRgamma proteins to varying degree in a cell context dependent manner, with U87MG glioma cells expressing both orphan nuclear receptors. Cell proliferation assays were performed in the presence of ERR isoform-specific agonists and antagonists, and the calculated EC(50) and IC(50) values were consistent with previous reported values determined in other types of cancer cell lines. Induction of luciferase expression under the control of ERR isoform-specific promoters was also observed in these cells. These results indicate that ERRalpha and ERRgamma are differentially expressed in these tumor cell lines and likely contribute to agonist-dependent ERR transcriptional activity.
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Affiliation(s)
- Mukesh K Gandhari
- Laboratory of Clinical Investigation, Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, Maryland 21224, USA
| | - Chester R Frazier
- Laboratory of Clinical Investigation, Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, Maryland 21224, USA
| | - Julia S Hartenstein
- Laboratory of Clinical Investigation, Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, Maryland 21224, USA
| | - Jean-Francois Cloix
- Laboratoire de Neurobiologie, Université d'Orléans, BP 6759, 45067 Orléans Cedex 2, France
| | - Michel Bernier
- Laboratory of Clinical Investigation, Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, Maryland 21224, USA
| | - Irving W. Wainer
- Laboratory of Clinical Investigation, Biomedical Research Center, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100, Baltimore, Maryland 21224, USA
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435
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Tremblay AM, Dufour CR, Ghahremani M, Reudelhuber TL, Giguère V. Physiological genomics identifies estrogen-related receptor alpha as a regulator of renal sodium and potassium homeostasis and the renin-angiotensin pathway. Mol Endocrinol 2010; 24:22-32. [PMID: 19901197 PMCID: PMC5428150 DOI: 10.1210/me.2009-0254] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 10/05/2009] [Indexed: 01/15/2023] Open
Abstract
Estrogen-related receptor alpha (ERRalpha) is an orphan nuclear receptor highly expressed in the kidney, an organ playing a central role in blood pressure regulation through electrolyte homeostasis and the renin-angiotensin system. Physiological analysis revealed that, relative to wild-type mice, ERRalpha null mice are hypotensive despite significant hypernatremia, hypokalemia, and slight hyperreninemia. Using a combination of genome-wide location analysis and expression profiling, we demonstrate that ERRalpha regulates the expression of channels involved in renal Na(+) and K(+) handling (Scnn1a, Atp1a1, Atp1b1) and altered in Bartter syndrome (Bsnd, Kcnq1). In addition, ERRalpha regulates the expression of receptors implicated in the systemic regulation of blood pressure (Ghr, Gcgr, Lepr, Npy1r) and of genes within the renin-angiotensin pathway (Ren1, Agt, Ace2). Our study thus identifies ERRalpha as a pleiotropic regulator of renal control of blood pressure, renal Na(+)/K(+) homeostasis, and renin-angiotensin pathway and suggests that modulation of ERRalpha activity could represent a potential avenue for the management of hypertension.
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Affiliation(s)
- Annie M Tremblay
- Rosalind and Goodman Cancer Centre, McGill University, Montréal, Québec, Canada
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436
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Teyssier C, Gallet M, Rabier B, Monfoulet L, Dine J, Macari C, Espallergues J, Horard B, Giguère V, Cohen-Solal M, Chassande O, Vanacker JM. Absence of ERRalpha in female mice confers resistance to bone loss induced by age or estrogen-deficiency. PLoS One 2009; 4:e7942. [PMID: 19936213 PMCID: PMC2776272 DOI: 10.1371/journal.pone.0007942] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Accepted: 10/13/2009] [Indexed: 01/20/2023] Open
Abstract
Background ERRα is an orphan member of the nuclear hormone receptor superfamily, which acts as a transcription factor and is involved in various metabolic processes. ERRα is also highly expressed in ossification zones during mouse development as well as in human bones and cell lines. Previous data have shown that this receptor up-modulates the expression of osteopontin, which acts as an inhibitor of bone mineralization and whose absence results in resistance to ovariectomy-induced bone loss. Altogether this suggests that ERRα may negatively regulate bone mass and could impact on bone fragility that occurs in the absence of estrogens. Methods/Principal Findings In this report, we have determined the in vivo effect of ERRα on bone, using knock-out mice. Relative to wild type animals, female ERRαKO bones do not age and are resistant to bone loss induced by estrogen-withdrawal. Strikingly male ERRαKO mice are indistinguishable from their wild type counterparts, both at the unchallenged or gonadectomized state. Using primary cell cultures originating from ERRαKO bone marrow, we also show that ERRα acts as an inhibitor of osteoblast differentiation. Conclusion/Significance Down-regulating ERRα could thus be beneficial against osteoporosis.
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Affiliation(s)
- Catherine Teyssier
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Marlène Gallet
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Bénédicte Rabier
- Institut National de la Santé et de la Recherche Médicale U 577, Université Victor Segalen Bordeaux II, Bordeaux, France
| | - Laurent Monfoulet
- Institut National de la Santé et de la Recherche Médicale U 577, Université Victor Segalen Bordeaux II, Bordeaux, France
| | - Julien Dine
- Institut National de la Santé et de la Recherche Médicale U 577, Université Victor Segalen Bordeaux II, Bordeaux, France
| | - Claire Macari
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Julie Espallergues
- Institut National de la Santé et de la Recherche Médicale U710, Université de Montpellier II, Montpellier, France
| | - Béatrice Horard
- Laboratoire de Biologie Moléculaire de la Cellule, CNRS UMR5239, Ecole Normale Supérieure de Lyon, Villeurbanne, France
| | - Vincent Giguère
- The Rosalind and Morris Goodman Cancer Centre, Montréal, Canada
| | - Martine Cohen-Solal
- Institut National de la Santé et de la Recherche Médicale U606, Hôpital Lariboisière, Paris, France
| | - Olivier Chassande
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, Lyon, France
- Institut National de la Santé et de la Recherche Médicale U 577, Université Victor Segalen Bordeaux II, Bordeaux, France
| | - Jean-Marc Vanacker
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon 1, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Ecole Normale Supérieure de Lyon, Lyon, France
- * E-mail:
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437
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Structural activity relationship of flavonoids with estrogen-related receptor gamma. FEBS Lett 2009; 584:22-6. [DOI: 10.1016/j.febslet.2009.11.026] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 10/28/2009] [Accepted: 11/07/2009] [Indexed: 01/16/2023]
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438
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Wu F, Wang J, Wang Y, Kwok TT, Kong SK, Wong C. Estrogen-related receptor alpha (ERRalpha) inverse agonist XCT-790 induces cell death in chemotherapeutic resistant cancer cells. Chem Biol Interact 2009; 181:236-42. [PMID: 19464277 DOI: 10.1016/j.cbi.2009.05.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Revised: 05/06/2009] [Accepted: 05/08/2009] [Indexed: 01/24/2023]
Abstract
Estrogen-related receptor alpha (ERRalpha) is primarily thought to regulate energy homeostasis through interacting with peroxisome proliferator-activated receptor gamma coactivator-1alpha and -1beta (PGC-1alpha and -1beta). They coordinately control the transcription of genes in the oxidative phosphorylation pathway. In addition to its role in energy metabolism, ERRalpha has also been implicated as a prognostic marker for breast, ovarian, colon and prostate cancers. In this study, we found that an ERRalpha inverse agonist XCT-790 induced cell death in HepG2 hepatocarcinoma and its multi-drug resistance (MDR) sub-line R-HepG2. Using a dye Mitotracker Green which stains mitochondrion independent of mitochondrial membrane potential (DeltaPsi(m)), we found that XCT-790 dose-dependently decreased mitochondrial mass. Intriguingly, XCT-790 increased DeltaPsi(m) upon short term treatment but decreased DeltaPsi(m) upon longer term treatment. The changes of DeltaPsi(m) in turn promoted the production of reactive oxygen species (ROS) and led to ROS-mediated caspases 3/7, 8, 9 activation and cell death. Importantly, we established that an anti-oxidative compound Mn(III) Tetra(4-benzoic acid) porphyrin chloride (MnTBAP) blocked the caspases activities and cell death increased by XCT-790 treatment. Finally, we found that XCT-790 synergized with paclitaxel to induce cell death in multi-drug resistance sub-line R-HepG2. Our results provide a conceptual framework for further developing chemotherapeutics based on suppressing ERRalpha activity.
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Affiliation(s)
- Feng Wu
- Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Science City, China
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439
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Abstract
Mitochondria play central roles in energy homeostasis, metabolism, signaling, and apoptosis. Accordingly, the abundance, morphology, and functional properties of mitochondria are finely tuned to meet cell-specific energetic, metabolic, and signaling demands. This tuning is largely achieved at the level of transcriptional regulation. A highly interconnected network of transcription factors regulates a broad set of nuclear genes encoding mitochondrial proteins, including those that control replication and transcription of the mitochondrial genome. The same transcriptional network senses cues relaying cellular energy status, nutrient availability, and the physiological state of the organism and enables short- and long-term adaptive responses, resulting in adjustments to mitochondrial function and mitochondrial biogenesis. Mitochondrial dysfunction is associated with many human diseases. Characterization of the transcriptional mechanisms that regulate mitochondrial biogenesis and function can offer insights into possible therapeutic interventions aimed at modulating mitochondrial function.
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Affiliation(s)
- M Benjamin Hock
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
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440
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Hakimov HA, Walters S, Wright TC, Meidinger RG, Verschoor CP, Gadish M, Chiu DKY, Strömvik MV, Forsberg CW, Golovan SP. Application of iTRAQ to catalogue the skeletal muscle proteome in pigs and assessment of effects of gender and diet dephytinization. Proteomics 2009; 9:4000-16. [DOI: 10.1002/pmic.200900049] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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441
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Xie YB, Park JH, Kim DK, Hwang JH, Oh S, Park SB, Shong M, Lee IK, Choi HS. Transcriptional corepressor SMILE recruits SIRT1 to inhibit nuclear receptor estrogen receptor-related receptor gamma transactivation. J Biol Chem 2009; 284:28762-74. [PMID: 19690166 DOI: 10.1074/jbc.m109.034165] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
SMILE (small heterodimer partner interacting leucine zipper protein) has been identified as a corepressor of the glucocorticoid receptor, constitutive androstane receptor, and hepatocyte nuclear factor 4alpha. Here we show that SMILE also represses estrogen receptor-related receptor gamma (ERRgamma) transactivation. Knockdown of SMILE gene expression increases ERRgamma activity. SMILE directly interacts with ERRgamma in vitro and in vivo. Domain mapping analysis showed that SMILE binds to the AF2 domain of ERRgamma. SMILE represses ERRgamma transactivation partially through competition with coactivators PGC-1alpha, PGC-1beta, and GRIP1. Interestingly, the repression of SMILE on ERRgamma is released by SIRT1 inhibitors, a catalytically inactive SIRT1 mutant, and SIRT1 small interfering RNA but not by histone protein deacetylase inhibitor. In vivo glutathione S-transferase pulldown and coimmunoprecipitation assays validated that SMILE physically interacts with SIRT1. Furthermore, the ERRgamma inverse agonist GSK5182 enhances the interaction of SMILE with ERRgamma and SMILE-mediated repression. Knockdown of SMILE or SIRT1 blocks the repressive effect of GSK5182. Moreover, chromatin immunoprecipitation assays revealed that GSK5182 augments the association of SMILE and SIRT1 on the promoter of the ERRgamma target PDK4. GSK5182 and adenoviral overexpression of SMILE cooperate to repress ERRgamma-induced PDK4 gene expression, and this repression is released by overexpression of a catalytically defective SIRT1 mutant. Finally, we demonstrated that ERRgamma regulates SMILE gene expression, which in turn inhibits ERRgamma. Overall, these findings implicate SMILE as a novel corepressor of ERRgamma and recruitment of SIRT1 as a novel repressive mechanism for SMILE and ERRgamma inverse agonist.
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Affiliation(s)
- Yuan-Bin Xie
- Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Republic of Korea
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442
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Deblois G, Hall JA, Perry MC, Laganière J, Ghahremani M, Park M, Hallett M, Giguère V. Genome-wide identification of direct target genes implicates estrogen-related receptor alpha as a determinant of breast cancer heterogeneity. Cancer Res 2009; 69:6149-57. [PMID: 19622763 DOI: 10.1158/0008-5472.can-09-1251] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Estrogen-related receptor alpha (ERRalpha) is an orphan nuclear receptor, the expression of which correlates with negative prognosis in breast cancer. ERRalpha shares functional features with the estrogen receptor alpha (ERalpha) and its activity is modulated by the ERBB2 signaling pathway. Using genome-wide binding sites location analyses in ERalpha-positive and ERalpha-negative breast cancer cell lines, we show that ERRalpha and ERalpha display strict binding site specificity and maintain independent mechanisms of transcriptional activation. Nonetheless, ERRalpha and ERalpha coregulate a small subset of common target genes via binding either to a dual-specificity binding site or to distinct cognate binding sites located within the extended promoter region of the gene. Although ERRalpha signaling in breast cancer cells is mostly independent of ERalpha, the small fraction of common ERRalpha/ERalpha targets comprises genes with high relevance to breast tumor biology, including genes located within the ERBB2 amplicon and GATA3. Finally, unsupervised hierarchical clustering based on the expression profiling of ERRalpha direct target genes in human breast tumors revealed four main clusters that recapitulate established tumor subtypes. Taken together, the identification and functional characterization of the ERRalpha transcriptional network implicate ERRalpha signaling as a determinant of breast cancer heterogeneity.
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Affiliation(s)
- Geneviève Deblois
- Rosalind and Morris Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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443
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Abstract
Bisphenol A (BPA) is a component of polycarbonate and other plastics including resins that line food and beverage containers. BPA is known to leach from products in contact with food and drink, and is therefore thought to be routinely ingested. In a recent cross sectional study, BPA was detected in urine samples from 92.6% of the US population examined. The potential for BPA to influence body weight is suggested by in vitro studies demonstrating effects of BPA on adipocyte differentiation, lipid accumulation, glucose transport and adiponectin secretion. Data from in vivo studies have revealed dose-dependent and sex dependent effects on body weight in rodents exposed perinatally to BPA. The mechanisms through which perinatal BPA exposure acts to exert persistent effects on body weight and adiposity remain to be determined. Possible targets of BPA action are discussed.
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Affiliation(s)
- Beverly S Rubin
- Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, MA 02111, United States.
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444
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Bcl3 interacts cooperatively with peroxisome proliferator-activated receptor gamma (PPARgamma) coactivator 1alpha to coactivate nuclear receptors estrogen-related receptor alpha and PPARalpha. Mol Cell Biol 2009; 29:4091-102. [PMID: 19451226 DOI: 10.1128/mcb.01669-08] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Estrogen-related receptors (ERRs) play critical roles in regulation of cellular energy metabolism in response to inducible coactivators such as peroxisome proliferator-activated receptor gamma (PPARgamma) coactivator 1alpha (PGC-1alpha). A yeast two-hybrid screen led to the identification of the cytokine-stimulated transcriptional regulator, Bcl3, as an ERRalpha coactivator. Bcl3 was shown to synergize with PGC-1alpha to coactivate ERRalpha. Chromatin immunoprecipitation studies demonstrated that ERRalpha, PGC-1alpha, and Bcl3 form a complex on an ERRalpha-responsive element within the pyruvate dehydrogenase kinase 4 gene promoter in cardiac myocytes. Mapping studies demonstrated that Bc13 interacts with PGC-1alpha and ERRalpha, allowing for interaction with both proteins. Transcriptional profiling demonstrated that Bcl3 activates genes involved in diverse pathways including a subset involved in cellular energy metabolism known to be regulated by PGC-1alpha, ERRalpha, and a second nuclear receptor, PPARalpha. Consistent with the gene expression profiling results, Bcl3 was shown to synergistically coactivate PPARalpha with PGC-1alpha in a manner similar to ERRalpha. We propose that the cooperativity between Bcl3 and PGC-1alpha may serve as a point of convergence on nuclear receptor targets to direct programs orchestrating inflammatory and energy metabolism responses in heart and other tissues.
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445
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Feingold KR, Moser A, Patzek SM, Shigenaga JK, Grunfeld C. Infection decreases fatty acid oxidation and nuclear hormone receptors in the diaphragm. J Lipid Res 2009; 50:2055-63. [PMID: 19443862 DOI: 10.1194/jlr.m800655-jlr200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Respiratory failure is a major cause of mortality during septic shock and is due in part to decreased ventilatory muscle contraction. Ventilatory muscles have high energy demands; fatty acid (FA) oxidation is an important source of ATP. FA oxidation is regulated by nuclear hormone receptors; studies have shown that the expression of these receptors is decreased in liver, heart, and kidney during sepsis. Here, we demonstrate that lipopolysaccharide (LPS) decreases FA oxidation and the expression of lipoprotein lipase (LPL), FA transport protein 1 (FATP-1), CD36, carnitine palmitoyltransferase beta, medium chain acyl-CoA dehydrogenase (MCAD), and acyl-CoA synthetase, key proteins required for FA uptake and oxidation, in the diaphragm. LPS also decreased mRNA levels of PPARalpha and beta/delta, RXRalpha, beta, and gamma, thyroid hormone receptor alpha and beta, and estrogen related receptor alpha (ERRalpha) and their coactivators PGC-1alpha, PGC-1beta, SRC1, SRC2, Lipin 1, and CBP. Zymosan resulted in similar changes in the diaphragm. Finally, in PPARalpha deficient mice, baseline CPT-1beta and FATP-1 levels were markedly decreased and were not further reduced by LPS suggesting that a decrease in the PPARalpha signaling pathway plays an important role in inducing some of these changes. The decrease in FA oxidation in the diaphragm may be detrimental, leading to decreased diaphragm contraction and an increased risk of respiratory failure during sepsis.
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Affiliation(s)
- Kenneth R Feingold
- Metabolism Section, Department of Veterans Affairs Medical Center, University of California San Francisco, San Francisco, CA 94121, USA.
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446
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Wang J, Fang F, Huang Z, Wang Y, Wong C. Kaempferol is an estrogen-related receptor alpha and gamma inverse agonist. FEBS Lett 2009; 583:643-7. [PMID: 19171140 DOI: 10.1016/j.febslet.2009.01.030] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 01/13/2009] [Accepted: 01/17/2009] [Indexed: 12/20/2022]
Abstract
Kaempferol is a dietary flavonoid that is thought to function as a selective estrogen receptor modulator. In this study, we established that kaempferol also functions as an inverse agonist for estrogen-related receptors alpha and gamma (ERRalpha and ERRgamma). We demonstrated that kaempferol binds to ERRalpha and ERRgamma and blocks their interaction with coactivator peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha). Kaempferol also suppressed the expressions of ERR-target genes pyruvate dehydrogenase kinase 2 and 4 (PDK2 and PDK4). This evidence suggests that kaempferol may exert some of its biological effect through both estrogen receptors and estrogen-related receptors.
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Affiliation(s)
- Junjian Wang
- Center of Integrative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510663, China
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Jarzabek K, Koda M, Kozlowski L, Sulkowski S, Kottler ML, Wolczynski S. The significance of the expression of ERRalpha as a potential biomarker in breast cancer. J Steroid Biochem Mol Biol 2009; 113:127-33. [PMID: 19138740 DOI: 10.1016/j.jsbmb.2008.12.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2008] [Revised: 11/17/2008] [Accepted: 12/15/2008] [Indexed: 12/27/2022]
Abstract
It was shown the functional crosstalk between ERRalpha and ERalpha in breast cancer, however, the biological significance of estrogen-related receptor alpha (ERRalpha) remains largely unclear. Therefore, we examined the expression of ERRalpha in 39 primary human breast cancer tissues and 19 matched normal tissues using RT-PCR and immunohistochemistry in the context of the aromatase, ERalpha and proliferation markers (c-myc, Ki-67) expression. Compared to the normal breast tissue, breast cancer tissues showed a slightly higher expression level of ERRalpha mRNA (mean 46.2+/-S.D.42.0, 57.7+/-S.D.58.7, respectively). However, ERRalpha mRNA levels in breast cancer tissues showed greater diversity than in normal tissues. Immunohistochemical analysis of breast cancers revealed perinuclear and cytoplasmic localization of ERRalpha. Our study shows that there is no correlation between ERRalpha and ERalpha expression. We demonstrated a positive correlation between ERRalpha and c-myc at the transcriptional level and statistically significant positive correlation between aromatase and the ERRalpha at protein level. It seems that ERRalpha could play an important role in the alternative pathway to classical estrogen receptors-dependent pathway in cell signaling. Development and use of ERRs modulators might lead in the future to design new well-tolerated and individualized therapeutic agents.
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Affiliation(s)
- Katarzyna Jarzabek
- Department of Reproduction and Gynaecological Endocrinology, Medical University of Bialystok, Sklodowskiej 24A, 15-276 Bialystok, Poland
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