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Corbin J, Yu X, Jin J, Cai L, Wang GG. EZH2 PROTACs target EZH2- and FOXM1-associated oncogenic nodes, suppressing breast cancer cell growth. Oncogene 2024; 43:2722-2736. [PMID: 39112519 DOI: 10.1038/s41388-024-03119-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 07/24/2024] [Accepted: 07/29/2024] [Indexed: 09/01/2024]
Abstract
Breast cancer (BC) remains the second leading cause of cancer-related mortalities in women. Resistance to hormone therapies such as tamoxifen, an estrogen receptor (ER) inhibitor, is a major hurdle in the treatment of BC. Enhancer of zeste homolog 2 (EZH2), the methyltransferase component of the Polycomb repressive complex 2 (PRC2), has been implicated in tamoxifen resistance. Evidence suggests that EZH2 often functions noncanonically, in a methyltransferase-independent manner, as a transcription coactivator through interacting with oncogenic transcription factors. Unlike methyltransferase inhibitors, proteolysis targeting chimeras (PROTAC) can suppress both activating and repressive functions of EZH2. Here, we find that EZH2 PROTACs, MS177 and MS8815, effectively inhibited the growth of BC cells, including those with acquired tamoxifen resistance, to a much greater degree when compared to methyltransferase inhibitors. Mechanistically, EZH2 associates with forkhead box M1 (FOXM1) and binds to the promoters of FOXM1 target genes. EZH2 PROTACs induce degradation of both EZH2 and FOXM1, leading to reduced expression of target genes involved in cell cycle progression and tamoxifen resistance. Together, this study supports that EZH2-targeted PROTACs represent a promising avenue of research for the future treatment of BC, including in the setting of tamoxifen resistance.
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Affiliation(s)
- Joshua Corbin
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, 27710, USA
- Duke Cancer Institute, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Xufen Yu
- Departments of Pharmacological Sciences and Oncological Sciences, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Mount Sinai Center for Therapeutics Discovery, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Jian Jin
- Departments of Pharmacological Sciences and Oncological Sciences, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Mount Sinai Center for Therapeutics Discovery, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Ling Cai
- Duke Cancer Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
- Department of Pathology, Duke University School of Medicine, Durham, NC, 27710, USA.
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, 27599, USA.
| | - Gang Greg Wang
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, 27710, USA.
- Duke Cancer Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
- Department of Pathology, Duke University School of Medicine, Durham, NC, 27710, USA.
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, 27599, USA.
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2
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Li Z, Li T, Yates ME, Wu Y, Ferber A, Chen L, Brown DD, Carroll JS, Sikora MJ, Tseng GC, Oesterreich S, Lee AV. The EstroGene Database Reveals Diverse Temporal, Context-Dependent, and Bidirectional Estrogen Receptor Regulomes in Breast Cancer. Cancer Res 2023; 83:2656-2674. [PMID: 37272757 PMCID: PMC10527051 DOI: 10.1158/0008-5472.can-23-0539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/21/2023] [Accepted: 06/01/2023] [Indexed: 06/06/2023]
Abstract
As one of the most successful cancer therapeutic targets, estrogen receptor-α (ER/ESR1) has been extensively studied over the past few decades. Sequencing technological advances have enabled genome-wide analysis of ER action. However, comparison of individual studies is limited by different experimental designs, and few meta-analyses are available. Here, we established the EstroGene database through unified processing of data from 246 experiments including 136 transcriptomic, cistromic, and epigenetic datasets focusing on estradiol (E2)-triggered ER activation across 19 breast cancer cell lines. A user-friendly browser (https://estrogene.org/) was generated for multiomic data visualization involving gene inquiry under user-defined experimental conditions and statistical thresholds. Notably, annotation of metadata associated with public datasets revealed a considerable lack of experimental details. Comparison of independent RNA-seq or ER ChIP-seq data with the same design showed large variability and only strong effects could be consistently detected. Temporal estrogen response metasignatures were defined, and the association of E2 response rate with temporal transcriptional factors, chromatin accessibility, and heterogeneity of ER expression was evaluated. Unexpectedly, harmonizing 146 E2-induced transcriptomic datasets uncovered a subset of genes harboring bidirectional E2 regulation, which was linked to unique transcriptional factors and highly associated with immune surveillance in the clinical setting. Furthermore, the context dependent E2 response programs were characterized in MCF7 and T47D cell lines, the two most frequently used models in the EstroGene database. Collectively, the EstroGene database provides an informative and practical resource to the cancer research community to uniformly evaluate key reproducible features of ER regulomes and unravels modes of ER signaling. SIGNIFICANCE A resource database integrating 246 publicly available ER profiling datasets facilitates meta-analyses and identifies estrogen response temporal signatures, a bidirectional program, and model-specific biases.
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Affiliation(s)
- Zheqi Li
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
| | - Tianqin Li
- School of Computer Science, Carnegie Mellon University, Pittsburgh PA, USA
| | - Megan E. Yates
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Integrative Systems Biology Program, University of Pittsburgh, Pittsburgh, PA, USA
- Medical Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yang Wu
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- School of Medicine, Tsinghua University, Beijing, China
| | - Amanda Ferber
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
| | - Lyuqin Chen
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
| | - Daniel D. Brown
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Institute for Precision Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jason S. Carroll
- Cancer Research UK, Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Matthew J. Sikora
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - George C. Tseng
- Department of Biostatistics, University of Pittsburgh, Pittsburgh PA, USA
| | - Steffi Oesterreich
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Integrative Systems Biology Program, University of Pittsburgh, Pittsburgh, PA, USA
| | - Adrian V. Lee
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Integrative Systems Biology Program, University of Pittsburgh, Pittsburgh, PA, USA
- Institute for Precision Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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3
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Schmidhauser M, Hankele AK, Ulbrich SE. Reconsidering "low-dose"-Impacts of oral estrogen exposure during preimplantation embryo development. Mol Reprod Dev 2023; 90:445-458. [PMID: 36864780 DOI: 10.1002/mrd.23675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 02/06/2023] [Indexed: 03/04/2023]
Abstract
Perturbations of estrogen signaling during developmental stages of high plasticity may lead to adverse effects later in life. Endocrine-disrupting chemicals (EDC) are compounds that interfere with the endocrine system by particularly mimicking the action of endogenous estrogens as functional agonists or antagonists. EDCs compose synthetic and naturally occurring compounds discharged into the environment, which may be taken up via skin contact, inhalation, orally due to contaminated food or water, or via the placenta during in utero development. Although estrogens are efficiently metabolized by the liver, the role of circulating glucuro- and/or sulpho-conjugated estrogen metabolites in the body has not been fully addressed to date. Particularly, the role of intracellular cleavage to free functional estrogens could explain the hitherto unknown mode of action of adverse effects of EDC at very low concentrations currently considered safe. We summarize and discuss findings on estrogenic EDC with a focus on early embryonic development to highlight the need for reconsidering low dose effects of EDC.
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Affiliation(s)
- Meret Schmidhauser
- ETH Zurich, Animal Physiology, Institute of Agricultural Sciences, Zurich, Switzerland
| | | | - Susanne E Ulbrich
- ETH Zurich, Animal Physiology, Institute of Agricultural Sciences, Zurich, Switzerland
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4
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Li Z, Li T, Yates ME, Wu Y, Ferber A, Chen L, Brown DD, Carroll JS, Sikora MJ, Tseng GC, Oesterreich S, Lee AV. EstroGene database reveals diverse temporal, context-dependent and directional estrogen receptor regulomes in breast cancer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.30.526388. [PMID: 36778377 PMCID: PMC9915613 DOI: 10.1101/2023.01.30.526388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
As one of the most successful cancer therapeutic targets, estrogen receptor-α (ER/ESR1) has been extensively studied in decade-long. Sequencing technological advances have enabled genome-wide analysis of ER action. However, reproducibility is limited by different experimental design. Here, we established the EstroGene database through centralizing 246 experiments from 136 transcriptomic, cistromic and epigenetic datasets focusing on estradiol-treated ER activation across 19 breast cancer cell lines. We generated a user-friendly browser ( https://estrogene.org/ ) for data visualization and gene inquiry under user-defined experimental conditions and statistical thresholds. Notably, documentation-based meta-analysis revealed a considerable lack of experimental details. Comparison of independent RNA-seq or ER ChIP-seq data with the same design showed large variability and only strong effects could be consistently detected. We defined temporal estrogen response metasignatures and showed the association with specific transcriptional factors, chromatin accessibility and ER heterogeneity. Unexpectedly, harmonizing 146 transcriptomic analyses uncovered a subset of E2-bidirectionally regulated genes, which linked to immune surveillance in the clinical setting. Furthermore, we defined context dependent E2 response programs in MCF7 and T47D cell lines, the two most frequently used models in the field. Collectively, the EstroGene database provides an informative resource to the cancer research community and reveals a diverse mode of ER signaling.
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Affiliation(s)
- Zheqi Li
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
| | - Tianqin Li
- School of Computer Science, Carnegie Mellon University, Pittsburgh PA, USA
| | - Megan E. Yates
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Integrative Systems Biology Program, University of Pittsburgh, Pittsburgh, PA, USA
- Medical Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yang Wu
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- School of Medicine, Tsinghua University, Beijing, China
| | - Amanda Ferber
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
| | - Lyuqin Chen
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
| | - Daniel D. Brown
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Institute for Precision Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jason S. Carroll
- Cancer Research UK, Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Matthew J. Sikora
- Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - George C. Tseng
- Department of Biostatistics, University of Pittsburgh, Pittsburgh PA, USA
| | - Steffi Oesterreich
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Integrative Systems Biology Program, University of Pittsburgh, Pittsburgh, PA, USA
| | - Adrian V. Lee
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh PA, USA
- Women’s Cancer Research Center, Magee Women’s Research Institute, UPMC Hillman Cancer Center, Pittsburgh PA, USA
- Integrative Systems Biology Program, University of Pittsburgh, Pittsburgh, PA, USA
- Institute for Precision Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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5
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Chromatin modifiers – Coordinators of estrogen action. Biomed Pharmacother 2022; 153:113548. [DOI: 10.1016/j.biopha.2022.113548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 08/03/2022] [Accepted: 08/11/2022] [Indexed: 11/20/2022] Open
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6
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Segelle A, Núñez-Álvarez Y, Oldfield AJ, Webb KM, Voigt P, Luco RF. Histone marks regulate the epithelial-to-mesenchymal transition via alternative splicing. Cell Rep 2022; 38:110357. [PMID: 35172149 DOI: 10.1016/j.celrep.2022.110357] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 09/20/2021] [Accepted: 01/19/2022] [Indexed: 12/15/2022] Open
Abstract
Histone modifications impact final splicing decisions. However, there is little evidence of the driving role of these marks in inducing cell-specific splicing changes. Using CRISPR epigenome editing tools, we show in an epithelial-to-mesenchymal cell reprogramming system (epithelial-to-mesenchymal transition [EMT]) that a single change in H3K27ac or H3K27me3 levels right at the alternatively spliced exon is necessary and sufficient to induce a splicing change capable of recapitulating important aspects of EMT, such as cell motility and invasiveness. This histone-mark-dependent splicing effect is highly dynamic and mediated by direct recruitment of the splicing regulator PTB to its RNA binding sites. These results support a role for H3K27 marks in inducing a change in the cell's phenotype via regulation of alternative splicing. We propose the dynamic nature of chromatin as a rapid and reversible mechanism to coordinate the splicing response to cell-extrinsic cues, such as induction of EMT.
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Affiliation(s)
- Alexandre Segelle
- Institute of Human Genetics, University of Montpellier, Centre National de la Recherche Scientifique, Montpellier, France
| | - Yaiza Núñez-Álvarez
- Institute of Human Genetics, University of Montpellier, Centre National de la Recherche Scientifique, Montpellier, France
| | - Andrew J Oldfield
- Institute of Human Genetics, University of Montpellier, Centre National de la Recherche Scientifique, Montpellier, France
| | - Kimberly M Webb
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Philipp Voigt
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Reini F Luco
- Institute of Human Genetics, University of Montpellier, Centre National de la Recherche Scientifique, Montpellier, France.
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7
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Involvement of the MEN1 Gene in Hormone-Related Cancers: Clues from Molecular Studies, Mouse Models, and Patient Investigations. ENDOCRINES 2020. [DOI: 10.3390/endocrines1020007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
MEN1 mutation predisposes patients to multiple endocrine neoplasia type 1 (MEN1), a genetic syndrome associated with the predominant co-occurrence of endocrine tumors. Intriguingly, recent evidence has suggested that MEN1 could also be involved in the development of breast and prostate cancers, two major hormone-related cancers. The first clues as to its possible role arose from the identification of the physical and functional interactions between the menin protein, encoded by MEN1, and estrogen receptor α and androgen receptor. In parallel, our team observed that aged heterozygous Men1 mutant mice developed cancerous lesions in mammary glands of female and in the prostate of male mutant mice at low frequencies, in addition to endocrine tumors. Finally, observations made both in MEN1 patients and in sporadic breast and prostate cancers further confirmed the role played by menin in these two cancers. In this review, we present the currently available data concerning the complex and multifaceted involvement of MEN1 in these two types of hormone-dependent cancers.
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8
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COCOA: coordinate covariation analysis of epigenetic heterogeneity. Genome Biol 2020; 21:240. [PMID: 32894181 PMCID: PMC7487606 DOI: 10.1186/s13059-020-02139-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 08/07/2020] [Indexed: 12/20/2022] Open
Abstract
A key challenge in epigenetics is to determine the biological significance of epigenetic variation among individuals. We present Coordinate Covariation Analysis (COCOA), a computational framework that uses covariation of epigenetic signals across individuals and a database of region sets to annotate epigenetic heterogeneity. COCOA is the first such tool for DNA methylation data and can also analyze any epigenetic signal with genomic coordinates. We demonstrate COCOA’s utility by analyzing DNA methylation, ATAC-seq, and multi-omic data in supervised and unsupervised analyses, showing that COCOA provides new understanding of inter-sample epigenetic variation. COCOA is available on Bioconductor (http://bioconductor.org/packages/COCOA).
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9
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Kovács T, Szabó-Meleg E, Ábrahám IM. Estradiol-Induced Epigenetically Mediated Mechanisms and Regulation of Gene Expression. Int J Mol Sci 2020; 21:ijms21093177. [PMID: 32365920 PMCID: PMC7246826 DOI: 10.3390/ijms21093177] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 04/22/2020] [Accepted: 04/28/2020] [Indexed: 12/20/2022] Open
Abstract
Gonadal hormone 17β-estradiol (E2) and its receptors are key regulators of gene transcription by binding to estrogen responsive elements in the genome. Besides the classical genomic action, E2 regulates gene transcription via the modification of epigenetic marks on DNA and histone proteins. Depending on the reaction partner, liganded estrogen receptor (ER) promotes DNA methylation at the promoter or enhancer regions. In addition, ERs are important regulators of passive and active DNA demethylation. Furthermore, ERs cooperating with different histone modifying enzymes and chromatin remodeling complexes alter gene transcription. In this review, we survey the basic mechanisms and interactions between estrogen receptors and DNA methylation, demethylation and histone modification processes as well as chromatin remodeling complexes. The particular relevance of these mechanisms to physiological processes in memory formation, embryonic development, spermatogenesis and aging as well as in pathophysiological changes in carcinogenesis is also discussed.
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Affiliation(s)
- Tamás Kovács
- Molecular Neuroendocrinology Research Group, Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Center, University of Pécs, H-7624 Pécs, Hungary;
| | - Edina Szabó-Meleg
- Department of Biophysics, Medical School, University of Pécs, H-7624 Pécs, Hungary;
| | - István M. Ábrahám
- Molecular Neuroendocrinology Research Group, Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Center, University of Pécs, H-7624 Pécs, Hungary;
- Correspondence:
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10
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Roopra A. MAGIC: A tool for predicting transcription factors and cofactors driving gene sets using ENCODE data. PLoS Comput Biol 2020; 16:e1007800. [PMID: 32251445 PMCID: PMC7162552 DOI: 10.1371/journal.pcbi.1007800] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 04/16/2020] [Accepted: 03/19/2020] [Indexed: 01/26/2023] Open
Abstract
Transcriptomic profiling is an immensely powerful hypothesis generating tool. However, accurately predicting the transcription factors (TFs) and cofactors that drive transcriptomic differences between samples is challenging. A number of algorithms draw on ChIP-seq tracks to define TFs and cofactors behind gene changes. These approaches assign TFs and cofactors to genes via a binary designation of 'target', or 'non-target' followed by Fisher Exact Tests to assess enrichment of TFs and cofactors. ENCODE archives 2314 ChIP-seq tracks of 684 TFs and cofactors assayed across a 117 human cell lines under a multitude of growth and maintenance conditions. The algorithm presented herein, Mining Algorithm for GenetIc Controllers (MAGIC), uses ENCODE ChIP-seq data to look for statistical enrichment of TFs and cofactors in gene bodies and flanking regions in gene lists without an a priori binary classification of genes as targets or non-targets. When compared to other TF mining resources, MAGIC displayed favourable performance in predicting TFs and cofactors that drive gene changes in 4 settings: 1) A cell line expressing or lacking single TF, 2) Breast tumors divided along PAM50 designations 3) Whole brain samples from WT mice or mice lacking a single TF in a particular neuronal subtype 4) Single cell RNAseq analysis of neurons divided by Immediate Early Gene expression levels. In summary, MAGIC is a standalone application that produces meaningful predictions of TFs and cofactors in transcriptomic experiments.
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Affiliation(s)
- Avtar Roopra
- Dept. of Neuroscience, 5507 WIMR, University of Wisconsin-Madison, Madison, United States of America
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11
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Dumasia K, Kumar A, Deshpande S, Balasinor NH. Estrogen, through estrogen receptor 1, regulates histone modifications and chromatin remodeling during spermatogenesis in adult rats. Epigenetics 2017; 12:953-963. [PMID: 28949791 DOI: 10.1080/15592294.2017.1382786] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Estrogen receptors (ESR1 and ESR2) play crucial roles in various processes during spermatogenesis. To elucidate individual roles of ESRs in male fertility, we developed in vivo selective ESR agonist administration models. Adult male rats treated with ESR1 and ESR2 agonist for 60 days show spermatogenic defects leading to reduced sperm counts and fertility. While studying epigenetic changes in the male germ line that could have affected fertility, we earlier observed a decrease in DNA methylation and its machinery upon ESR2 agonist treatment. Here, we explored the effects on histone modifications, which could contribute to decreased male fertility upon ESR agonist administration. ESR1 agonist treatment affected testicular levels of histone modifications associated with active and repressed chromatin states, along with heterochromatin marks. This was concomitant with deregulation of corresponding histone modifying enzymes in the testis. In addition, there was increased retention of histones along with protamine deficiency in the caudal spermatozoa after ESR1 agonist treatment. This could be due to the observed decrease in several chromatin remodeling proteins implicated in mediating histone-to-protamine exchange during spermiogenesis. The activating and repressing histone marks in spermatozoa, which play a critical role in early embryo development, were deregulated after both the ESR agonist treatments. Together, these epigenetic defects in the male germ line could affect the spermatozoa quality and lead to the observed decrease in fertility. Our results thus highlight the importance of ESRs in regulating different epigenetic processes during spermatogenesis, which are crucial for male fertility.
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Affiliation(s)
- Kushaan Dumasia
- a Department of Neuroendocrinology , National Institute for Research in Reproductive Health (Indian Council of Medical Research), Parel , Mumbai , India
| | - Anita Kumar
- a Department of Neuroendocrinology , National Institute for Research in Reproductive Health (Indian Council of Medical Research), Parel , Mumbai , India
| | - Sharvari Deshpande
- a Department of Neuroendocrinology , National Institute for Research in Reproductive Health (Indian Council of Medical Research), Parel , Mumbai , India
| | - Nafisa H Balasinor
- a Department of Neuroendocrinology , National Institute for Research in Reproductive Health (Indian Council of Medical Research), Parel , Mumbai , India
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12
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Abstract
Multiple mechanisms of epigenetic control that include DNA methylation, histone modification, noncoding RNAs, and mitotic gene bookmarking play pivotal roles in stringent gene regulation during lineage commitment and maintenance. Experimental evidence indicates that bivalent chromatin domains, i.e., genome regions that are marked by both H3K4me3 (activating) and H3K27me3 (repressive) histone modifications, are a key property of pluripotent stem cells. Bivalency of developmental genes during the G1 phase of the pluripotent stem cell cycle contributes to cell fate decisions. Recently, some cancer types have been shown to exhibit partial recapitulation of bivalent chromatin modifications that are lost along with pluripotency, suggesting a mechanism by which cancer cells reacquire properties that are characteristic of undifferentiated, multipotent cells. This bivalent epigenetic control of oncofetal gene expression in cancer cells may offer novel insights into the onset and progression of cancer and may provide specific and selective options for diagnosis as well as for therapeutic intervention.
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13
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Dubey N, Hoffman JF, Schuebel K, Yuan Q, Martinez PE, Nieman LK, Rubinow DR, Schmidt PJ, Goldman D. The ESC/E(Z) complex, an effector of response to ovarian steroids, manifests an intrinsic difference in cells from women with premenstrual dysphoric disorder. Mol Psychiatry 2017; 22:1172-1184. [PMID: 28044059 PMCID: PMC5495630 DOI: 10.1038/mp.2016.229] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 10/19/2016] [Accepted: 10/31/2016] [Indexed: 12/21/2022]
Abstract
Clinical evidence suggests that mood and behavioral symptoms in premenstrual dysphoric disorder (PMDD), a common, recently recognized, psychiatric condition among women, reflect abnormal responsivity to ovarian steroids. This differential sensitivity could be due to an unrecognized aspect of hormonal signaling or a difference in cellular response. In this study, lymphoblastoid cell line cultures (LCLs) from women with PMDD and asymptomatic controls were compared via whole-transcriptome sequencing (RNA-seq) during untreated (ovarian steroid-free) conditions and following hormone treatment. The women with PMDD manifested ovarian steroid-triggered behavioral sensitivity during a hormone suppression and addback clinical trial, and controls did not, leading us to hypothesize that women with PMDD might differ in their cellular response to ovarian steroids. In untreated LCLs, our results overall suggest a divergence between mRNA (for example, gene transcription) and protein (for example, RNA translation in proteins) for the same genes. Pathway analysis of the LCL transcriptome revealed, among others, over-expression of ESC/E(Z) complex genes (an ovarian steroid-regulated gene silencing complex) in untreated LCLs from women with PMDD, with more than half of these genes over-expressed as compared with the controls, and with significant effects for MTF2, PHF19 and SIRT1 (P<0.05). RNA and protein expression of the 13 ESC/E(Z) complex genes were individually quantitated. This pattern of increased ESC/E(Z) mRNA expression was confirmed in a larger cohort by qRT-PCR. In contrast, protein expression of ESC/E(Z) genes was decreased in untreated PMDD LCLs with MTF2, PHF19 and SIRT1 all significantly decreased (P<0.05). Finally, mRNA expression of several ESC/E(Z) complex genes were increased by progesterone in controls only, and decreased by estradiol in PMDD LCLs. These findings demonstrate that LCLs from women with PMDD manifest a cellular difference in ESC/E(Z) complex function both in the untreated condition and in response to ovarian hormones. Dysregulation of ESC/E(Z) complex function could contribute to PMDD.
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Affiliation(s)
| | | | | | | | | | - Lynnette K. Nieman
- Intramural Research Program on Reproductive and Adult Endocrinology, The Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, DHSS
| | - David R. Rubinow
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC
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14
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Kumar A, Dumasia K, Deshpande S, Balasinor NH. Direct regulation of genes involved in sperm release by estrogen and androgen through their receptors and coregulators. J Steroid Biochem Mol Biol 2017; 171:66-74. [PMID: 28242260 DOI: 10.1016/j.jsbmb.2017.02.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/08/2017] [Accepted: 02/23/2017] [Indexed: 12/23/2022]
Abstract
Steroid hormones, estrogen and androgen, control transcription in various reproductive and non-reproductive tissues. Both hormones are known to be important for control of sperm release from the seminiferous epithelium (spermiation), a process characterized by extensive remodeling of actin filaments and endocytosis. Earlier studies with an estrogen (E2)-induced rat model of spermiation failure revealed genes involved in actin remodeling (Arpc1b and Evl) and endocytosis (Picalm, Eea1, and Stx5a) to be differentially regulated. Further, among these genes, Arpc1b and Evl were found to be estrogen-responsive whereas Eea1 and Stx5a were androgen-responsive and Picalm was responsive to both hormones in seminiferous tubule cultures. Yet, the mechanism by which these genes are regulated by estrogen and androgen in the testis was unclear. Here, we report the presence of a functional estrogen response element (ERE) upstream of Arpc1b and Evl genes and androgen response element (ARE) upstream of Picalm, Eea1, and Stx5a genes. Chromatin immunoprecipitation in control versus E2-treated testes revealed significant changes in estrogen receptor beta (ERβ) recruitment along with coregulators to the EREs upstream of Arpc1b and Evl genes and androgen receptor (AR) at AREs upstream of Picalm, Eea1, and Stx5a genes. Enrichment patterns of these EREs/AREs with coregulators, activating and repressing histone modifications along with RNA polymerase II recruitment, correlated with the observed expression patterns of these genes upon E2 treatment. Taken together, our results reveal direct targets of estrogen and androgen in the testes and provide insights into transcriptional control of sperm release by the two steroid hormones.
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Affiliation(s)
- Anita Kumar
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health (ICMR), Parel, Mumbai 400012, India
| | - Kushaan Dumasia
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health (ICMR), Parel, Mumbai 400012, India
| | - Sharvari Deshpande
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health (ICMR), Parel, Mumbai 400012, India
| | - N H Balasinor
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health (ICMR), Parel, Mumbai 400012, India.
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15
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Gajulapalli VNR, Malisetty VL, Chitta SK, Manavathi B. Oestrogen receptor negativity in breast cancer: a cause or consequence? Biosci Rep 2016; 36:e00432. [PMID: 27884978 PMCID: PMC5180249 DOI: 10.1042/bsr20160228] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Revised: 11/23/2016] [Accepted: 11/24/2016] [Indexed: 02/07/2023] Open
Abstract
Endocrine resistance, which occurs either by de novo or acquired route, is posing a major challenge in treating hormone-dependent breast cancers by endocrine therapies. The loss of oestrogen receptor α (ERα) expression is the vital cause of establishing endocrine resistance in this subtype. Understanding the mechanisms that determine the causes of this phenomenon are therefore essential to reduce the disease efficacy. But how we negate oestrogen receptor (ER) negativity and endocrine resistance in breast cancer is questionable. To answer that, two important approaches are considered: (1) understanding the cellular origin of heterogeneity and ER negativity in breast cancers and (2) characterization of molecular regulators of endocrine resistance. Breast tumours are heterogeneous in nature, having distinct molecular, cellular, histological and clinical behaviour. Recent advancements in perception of the heterogeneity of breast cancer revealed that the origin of a particular mammary tumour phenotype depends on the interactions between the cell of origin and driver genetic hits. On the other hand, histone deacetylases (HDACs), DNA methyltransferases (DNMTs), miRNAs and ubiquitin ligases emerged as vital molecular regulators of ER negativity in breast cancers. Restoring response to endocrine therapy through re-expression of ERα by modulating the expression of these molecular regulators is therefore considered as a relevant concept that can be implemented in treating ER-negative breast cancers. In this review, we will thoroughly discuss the underlying mechanisms for the loss of ERα expression and provide the future prospects for implementing the strategies to negate ER negativity in breast cancers.
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Affiliation(s)
- Vijaya Narasihma Reddy Gajulapalli
- Department of Biochemistry, Molecular and Cellular Oncology Laboratory, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | | | - Suresh Kumar Chitta
- Department of Biochemistry, Sri Krishnadevaraya University, Anantapur, Andhra Pradesh 515002, India
| | - Bramanandam Manavathi
- Department of Biochemistry, Molecular and Cellular Oncology Laboratory, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
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16
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Ariazi EA, Taylor JC, Black MA, Nicolas E, Slifker MJ, Azzam DJ, Boyd J. A New Role for ERα: Silencing via DNA Methylation of Basal, Stem Cell, and EMT Genes. Mol Cancer Res 2016; 15:152-164. [PMID: 28108626 DOI: 10.1158/1541-7786.mcr-16-0283] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 10/10/2016] [Accepted: 10/18/2016] [Indexed: 12/30/2022]
Abstract
Resistance to hormonal therapies is a major clinical problem in the treatment of estrogen receptor α-positive (ERα+) breast cancers. Epigenetic marks, namely DNA methylation of cytosine at specific CpG sites (5mCpG), are frequently associated with ERα+ status in human breast cancers. Therefore, ERα may regulate gene expression in part via DNA methylation. This hypothesis was evaluated using a panel of breast cancer cell line models of antiestrogen resistance. Microarray gene expression profiling was used to identify genes normally silenced in ERα+ cells but derepressed upon exposure to the demethylating agent decitabine, derepressed upon long-term loss of ERα expression, and resuppressed by gain of ERα activity/expression. ERα-dependent DNA methylation targets (n = 39) were enriched for ERα-binding sites, basal-up/luminal-down markers, cancer stem cell, epithelial-mesenchymal transition, and inflammatory and tumor suppressor genes. Kaplan-Meier survival curve and Cox proportional hazards regression analyses indicated that these targets predicted poor distant metastasis-free survival among a large cohort of breast cancer patients. The basal breast cancer subtype markers LCN2 and IFI27 showed the greatest inverse relationship with ERα expression/activity and contain ERα-binding sites. Thus, genes that are methylated in an ERα-dependent manner may serve as predictive biomarkers in breast cancer. IMPLICATIONS ERα directs DNA methylation-mediated silencing of specific genes that have biomarker potential in breast cancer subtypes. Mol Cancer Res; 15(2); 152-64. ©2016 AACR.
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Affiliation(s)
- Eric A Ariazi
- Fox Chase Cancer Center, Temple University Health System, Philadelphia, Pennsylvania.
| | - John C Taylor
- Fox Chase Cancer Center, Temple University Health System, Philadelphia, Pennsylvania
| | - Michael A Black
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Emmanuelle Nicolas
- Fox Chase Cancer Center, Temple University Health System, Philadelphia, Pennsylvania
| | - Michael J Slifker
- Fox Chase Cancer Center, Temple University Health System, Philadelphia, Pennsylvania
| | - Diana J Azzam
- Department of Human and Molecular Genetics, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida
| | - Jeff Boyd
- Fox Chase Cancer Center, Temple University Health System, Philadelphia, Pennsylvania.
- Department of Human and Molecular Genetics, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida
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17
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Bavelloni A, Piazzi M, Raffini M, Faenza I, Blalock WL. Prohibitin 2: At a communications crossroads. IUBMB Life 2015; 67:239-54. [PMID: 25904163 DOI: 10.1002/iub.1366] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/06/2015] [Indexed: 01/02/2023]
Abstract
Prohibitins (PHBs) are a highly conserved class of proteins first discovered as inhibitors of cellular proliferation. Since then PHBs have been found to have a significant role in transcription, nuclear signaling, mitochondrial structural integrity, cell division, and cellular membrane metabolism, placing these proteins among the key regulators of pathologies such as cancer, neuromuscular degeneration, and other metabolic diseases. The human genome encodes two PHB proteins, prohibitin 1 (PHB1) and prohibitin 2 (PHB2), which function not only as a heterodimeric complex, but also independently. While many previous reviews have focused on the better characterized prohibitin, PHB1, this review focuses on PHB2 and new data concerning its cellular functions both in complex with PHB1 and independent of PHB1.
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Affiliation(s)
- Alberto Bavelloni
- Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute, Bologna, Italy.,Laboratory RAMSES, Rizzoli Orthopedic Institute, Bologna, Italy
| | - Manuela Piazzi
- Department of Biomedical Sciences, University of Bologna, Bologna, Italy
| | - Mirco Raffini
- Laboratory RAMSES, Rizzoli Orthopedic Institute, Bologna, Italy
| | - Irene Faenza
- Department of Biomedical Sciences, University of Bologna, Bologna, Italy
| | - William L Blalock
- Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute, Bologna, Italy.,National Research Council of Italy, Institute of Molecular Genetics, Bologna, Italy
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18
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Neo WH, Lim JF, Grumont R, Gerondakis S, Su IH. c-Rel regulates Ezh2 expression in activated lymphocytes and malignant lymphoid cells. J Biol Chem 2014; 289:31693-31707. [PMID: 25266721 DOI: 10.1074/jbc.m114.574517] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The polycomb group protein Ezh2 is a histone methyltransferase that modifies chromatin structure to alter gene expression during embryonic development, lymphocyte activation, and tumorigenesis. The mechanism by which Ezh2 expression is regulated is not well defined. In the current study, we report that c-Rel is a critical activator of Ezh2 transcription in lymphoid cells. In activated primary murine B and T cells, plus human leukemia and multiple myeloma cell lines, recruitment of c-Rel to the first intron of the Ezh2 locus promoted Ezh2 mRNA expression. This up-regulation was abolished in activated c-Rel-deficient lymphocytes and by c-Rel knockdown in Jurkat T cells. Treatment of malignant cells with the c-Rel inhibitor pentoxifylline not only reduced c-Rel nuclear translocation and Ezh2 expression, but also enhanced their sensitivity to the Ezh2-specific drug, GSK126 through increased growth inhibition and cell death. In summary, our demonstration that c-Rel regulates Ezh2 expression in lymphocytes and malignant lymphoid cells reveals a novel transcriptional network in transformed lymphoid cells expressing high levels of Ezh2 that provides a molecular justification for combinatorial drug therapy.
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Affiliation(s)
- Wen Hao Neo
- School of Biological Sciences, College of Science, Nanyang Technological University, Singapore 637551, Republic of Singapore and
| | - Jun Feng Lim
- School of Biological Sciences, College of Science, Nanyang Technological University, Singapore 637551, Republic of Singapore and
| | - Raelene Grumont
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria 3004, Australia
| | - Steve Gerondakis
- Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria 3004, Australia
| | - I-Hsin Su
- School of Biological Sciences, College of Science, Nanyang Technological University, Singapore 637551, Republic of Singapore and.
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19
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Chen YA, Murakami Y, Ahmad S, Yoshimaru T, Katagiri T, Mizuguchi K. Brefeldin A-inhibited guanine nucleotide-exchange protein 3 (BIG3) is predicted to interact with its partner through an ARM-type α-helical structure. BMC Res Notes 2014; 7:435. [PMID: 24997568 PMCID: PMC4096751 DOI: 10.1186/1756-0500-7-435] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 06/30/2014] [Indexed: 12/21/2022] Open
Abstract
Background Brefeldin A-inhibited guanine nucleotide-exchange protein 3 (BIG3) has been identified recently as a novel regulator of estrogen signalling in breast cancer cells. Despite being a potential target for new breast cancer treatment, its amino acid sequence suggests no association with any well-characterized protein family and provides little clues as to its molecular function. In this paper, we predicted the structure, function and interactions of BIG3 using a range of bioinformatic tools. Results Homology search results showed that BIG3 had distinct features from its paralogues, BIG1 and BIG2, with a unique region between the two shared domains, Sec7 and DUF1981. Although BIG3 contains Sec7 domain, the lack of the conserved motif and the critical glutamate residue suggested no potential guaninyl-exchange factor (GEF) activity. Fold recognition tools predicted BIG3 to adopt an α-helical repeat structure similar to that of the armadillo (ARM) family. Using state-of-the-art methods, we predicted interaction sites between BIG3 and its partner PHB2. Conclusions The combined results of the structure and interaction prediction led to a novel hypothesis that one of the predicted helices of BIG3 might play an important role in binding to PHB2 and thereby preventing its translocation to the nucleus. This hypothesis has been subsequently verified experimentally.
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Affiliation(s)
| | | | | | | | | | - Kenji Mizuguchi
- National Institute of Biomedical Innovation, 7-6-8 Saito-asagi, Ibaraki city, Osaka 567-0085, Japan.
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20
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Epigenetics of estrogen receptor signaling: role in hormonal cancer progression and therapy. Cancers (Basel) 2013; 3:1691-707. [PMID: 21814622 PMCID: PMC3147309 DOI: 10.3390/cancers3021691] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Estrogen receptor (ERα) signaling plays a key role in hormonal cancer progression. ERα is a ligand-dependent transcription factor that modulates gene transcription via recruitment to the target gene chromatin. Emerging evidence suggests that ERα signaling has the potential to contribute to epigenetic changes. Estrogen stimulation is shown to induce several histone modifications at the ERα target gene promoters including acetylation, phosphorylation and methylation via dynamic interactions with histone modifying enzymes. Deregulation of enzymes involved in the ERα-mediated epigenetic pathway could play a vital role in ERα driven neoplastic processes. Unlike genetic alterations, epigenetic changes are reversible, and hence offer novel therapeutic opportunities to reverse ERα driven epigenetic changes. In this review, we summarize current knowledge on mechanisms by which ERα signaling potentiates epigenetic changes in cancer cells via histone modifications.
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21
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Thuaud F, Ribeiro N, Nebigil CG, Désaubry L. Prohibitin ligands in cell death and survival: mode of action and therapeutic potential. ACTA ACUST UNITED AC 2013; 20:316-31. [PMID: 23521790 PMCID: PMC7111013 DOI: 10.1016/j.chembiol.2013.02.006] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 01/31/2013] [Accepted: 02/06/2013] [Indexed: 12/21/2022]
Abstract
Prohibitins (PHBs) are scaffold proteins that modulate many signaling pathways controlling cell survival, metabolism, and inflammation. Several drugs that target PHBs have been identified and evaluated for various clinical applications. Preclinical and clinical studies indicate that these PHB ligands may be useful in oncology, cardiology, and neurology, as well as against obesity. This review covers the physiological role of PHBs in health and diseases and current developments concerning PHB ligands.
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Affiliation(s)
- Frédéric Thuaud
- Therapeutic Innovation Laboratory UMR 7200, CNRS/Université de Strasbourg, Faculté de Pharmacie, 67401 Illkirch Cedex, France
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22
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Deb G, Thakur VS, Gupta S. Multifaceted role of EZH2 in breast and prostate tumorigenesis: epigenetics and beyond. Epigenetics 2013; 8:464-76. [PMID: 23644490 DOI: 10.4161/epi.24532] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Overexpression of EZH2 and other PRC2 subunits, such as SUZ12, is associated with tumor progression and poor prognosis in several human malignancies. Nevertheless, the underlying mechanisms driving aberrant EZH2 expression are poorly understood. This review provides molecular insights into the essential role of EZH2 in breast and prostate tumorigenesis. We addressed the current understanding on the oncogenic role of EZH2, with an emphasis on: (1) the less known PRC2-independent role of EZH2 in gene activation, in addition to its canonical role in transcriptional silencing as a histone methyltransferase catalyzing the trimethylation of histone H3 at lysine 27; (2) causes and consequences of its deregulation in tumor cells and; (3) collaboration of EZH2 with other epigenetic and hormone receptor-mediated oncogenic signaling pathways. We also summarize how EZH2 has emerged as a promising therapeutic target in hormone-refractory cancers and the prospects for integrating EZH2 blockade with available pharmacological inhibitors.
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Affiliation(s)
- Gauri Deb
- Department of Urology, Case Western Reserve University, Cleveland, OH, USA
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23
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Kashyap V, Laursen KB, Brenet F, Viale AJ, Scandura JM, Gudas LJ. RARγ is essential for retinoic acid induced chromatin remodeling and transcriptional activation in embryonic stem cells. J Cell Sci 2013; 126:999-1008. [PMID: 23264745 PMCID: PMC3625813 DOI: 10.1242/jcs.119701] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2012] [Indexed: 01/06/2023] Open
Abstract
We have utilized retinoic acid receptor γ (gamma) knockout (RARγ(-/-)) embryonic stem (ES) cells as a model system to analyze RARγ mediated transcriptional regulation of stem cell differentiation. Most of the transcripts regulated by all-trans retinoic acid (RA) in ES cells are dependent upon functional RARγ signaling. Notably, many of these RA-RARγ target genes are implicated in retinoid uptake and metabolism. For instance, Lrat (lecithin:retinol acyltransferase), Stra6 (stimulated by retinoic acid 6), Crabp2 (cellular retinoic acid binding protein 2), and Cyp26a1 (cytochrome p450 26a1) transcripts are induced in wild type (WT), but not in RARγ(-/-) cells. Transcripts for the transcription factors Pbx1 (pre-B cell leukemia homeobox-1), Wt1 (Wilm's tumor gene-1), and Meis1 (myeloid ecotropic viral integration site-1) increase upon RA treatment of WT, but not RARγ(-/-) cells. In contrast, Stra8, Dleu7, Leftb, Pitx2, and Cdx1 mRNAs are induced by RA even in the absence of RARγ. Mapping of the epigenetic signature of Meis1 revealed that RA induces a rapid increase in the H3K9/K14ac epigenetic mark at the proximal promoter and at two sites downstream of the transcription start site in WT, but not in RARγ(-/-) cells. Thus, RA-associated increases in H3K9/K14ac epigenetic marks require RARγ and are associated with increased Meis1 transcript levels, whereas H3K4me3 is present at the Meis1 proximal promoter even in the absence of RARγ. In contrast, at the Lrat proximal promoter primarily the H3K4me3 mark, and not the H3K9/K14ac mark, increases in response to RA, independently of the presence of RARγ. Our data show major epigenetic changes associated with addition of the RARγ agonist RA in ES cells.
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Affiliation(s)
- Vasundhra Kashyap
- Department of Pharmacology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA
- Weill Graduate School of Biomedical Sciences, 1300 York Avenue, New York, NY 10065, USA
| | - Kristian B. Laursen
- Department of Pharmacology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA
| | - Fabienne Brenet
- Department of Medicine, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA
| | - Agnes J. Viale
- Genomics Core Laboratory, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA
| | - Joseph M. Scandura
- Department of Medicine, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA
| | - Lorraine J. Gudas
- Department of Pharmacology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA
- Department of Medicine, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10065, USA
- Weill Graduate School of Biomedical Sciences, 1300 York Avenue, New York, NY 10065, USA
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24
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Manavathi B, Dey O, Gajulapalli VNR, Bhatia RS, Bugide S, Kumar R. Derailed estrogen signaling and breast cancer: an authentic couple. Endocr Rev 2013; 34:1-32. [PMID: 22947396 PMCID: PMC3565105 DOI: 10.1210/er.2011-1057] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 07/09/2012] [Indexed: 02/06/2023]
Abstract
Estrogen or 17β-estradiol, a steroid hormone, plays a critical role in the development of mammary gland via acting through specific receptors. In particular, estrogen receptor-α (ERα) acts as a transcription factor and/or a signal transducer while participating in the development of mammary gland and breast cancer. Accumulating evidence suggests that the transcriptional activity of ERα is altered by the action of nuclear receptor coregulators and might be responsible, at least in part, for the development of breast cancer. In addition, this process is driven by various posttranslational modifications of ERα, implicating active participation of the upstream receptor modifying enzymes in breast cancer progression. Emerging studies suggest that the biological outcome of breast cancer cells is also influenced by the cross talk between microRNA and ERα signaling, as well as by breast cancer stem cells. Thus, multiple regulatory controls of ERα render mammary epithelium at risk for transformation upon deregulation of normal homeostasis. Given the importance that ERα signaling has in breast cancer development, here we will highlight how the activity of ERα is controlled by various regulators in a spatial and temporal manner, impacting the progression of the disease. We will also discuss the possible therapeutic value of ERα modulators as alternative drug targets to retard the progression of breast cancer.
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Affiliation(s)
- Bramanandam Manavathi
- Department of Biochemistry, School of Life Sciences, Gachibowli, Prof. CR Rao Road, University of Hyderabad, Hyderabad 500046, India.
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25
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Hervouet E, Cartron PF, Jouvenot M, Delage-Mourroux R. Epigenetic regulation of estrogen signaling in breast cancer. Epigenetics 2013; 8:237-45. [PMID: 23364277 PMCID: PMC3669116 DOI: 10.4161/epi.23790] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Estrogen signaling is mediated by ERα and ERβ in hormone dependent, breast cancer (BC). Over the last decade the implication of epigenetic pathways in BC tumorigenesis has emerged: cancer-related epigenetic modifications are implicated in both gene expression regulation, and chromosomal instability. In this review, the epigenetic-mediated estrogen signaling, controlling both ER level and ER-targeted gene expression in BC, are discussed: (1) ER silencing is frequently observed in BC and is often associated with epigenetic regulations while chemical epigenetic modulators restore ER expression and increase response to treatment;(2) ER-targeted gene expression is tightly regulated by co-recruitment of ER and both coactivators/corepressors including HATs, HDACs, HMTs, Dnmts and Polycomb proteins.
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Affiliation(s)
- Eric Hervouet
- Université de Franche-Comté, Laboratoire de Biochimie, EA3922, Expression Génique et Pathologies du Système Nerveux Central, SFRIBCT FED 4234, UFR Sciences et Techniques, Besançon, France.
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26
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Li KK, Luo C, Wang D, Jiang H, Zheng YG. Chemical and biochemical approaches in the study of histone methylation and demethylation. Med Res Rev 2012; 32:815-67. [PMID: 22777714 DOI: 10.1002/mrr.20228] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Histone methylation represents one of the most critical epigenetic events in DNA function regulation in eukaryotic organisms. Classic molecular biology and genetics tools provide significant knowledge about mechanisms and physiological roles of histone methyltransferases and demethylases in various cellular processes. In addition to this stream line, development and application of chemistry and chemistry-related techniques are increasingly involved in biological study, and offer information otherwise difficult to obtain by standard molecular biology methods. Herein, we review recent achievements and progress in developing and applying chemical and biochemical approaches in the study of histone methylation, including chromatin immunoprecipitation, chemical ligation, mass spectrometry, biochemical methylation and demethylation assays, and inhibitor development. These technological advances allow histone methylation to be studied from genome-wide level to molecular and atomic levels. With ChIP technology, information can be obtained about precise mapping of histone methylation patterns at specific promoters, genes, or other genomic regions. MS is particularly useful in detecting and analyzing methylation marks in histone and nonhistone protein substrates. Chemical approaches that permit site-specific incorporation of methyl groups into histone proteins greatly facilitate the investigation of biological impacts of methylation at individual modification sites. Discovery and design of selective organic inhibitors of histone methyltransferases and demethylases provide chemical probes to interrogate methylation-mediated cellular pathways. Overall, these chemistry-related technological advances have greatly improved our understanding of the biological functions of histone methylation in normal physiology and diseased states, and also are of great potential to translate basic epigenetics research into diagnostic and therapeutic applications in the clinic.
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Affiliation(s)
- Keqin Kathy Li
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
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27
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Park S, Yoon S, Zhao Y, Park SE, Liao L, Xu J, Lydon JP, DeMayo FJ, O'Malley BW, Bagchi MK, Katzenellenbogen BS. Uterine development and fertility are dependent on gene dosage of the nuclear receptor coregulator REA. Endocrinology 2012; 153:3982-94. [PMID: 22585830 PMCID: PMC3404350 DOI: 10.1210/en.2012-1044] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although the effectiveness of nuclear hormone-receptor complexes is known to depend on coregulator partner proteins, relatively little is known about the roles of coregulators in uterine development and early stages of pregnancy and implantation. Because conventional genetic deletion of the coregulator, repressor of estrogen receptor activity (REA), was embryonic lethal, we here study REA conditional knockout mice generated by cre-loxP recombination, in which REA function was abrogated only in progesterone receptor-expressing tissues, to define the roles of REA in postembryonic stages and in a tissue-specific manner. We find that REA has gene dose-dependent activity impacting uterine development and fertility. Conditional homozygous mutant (REA(d/d)) mice developed to adulthood and showed normal ovarian function, but females were infertile with severely compromised uterine development and function characterized by cell cycle arrest, apoptosis, and altered adenogenesis (endometrial gland morphogenesis), resulting in failure of implantation and decidualization. By contrast, mice heterozygous for REA (REA(f/d)) had a very different phenotype, with estradiol treatment resulting in hyperstimulated, large uteri showing increased proliferation of luminal epithelial cells, and enhanced fluid imbibition associated with altered regulation of aquaporins. These REA(f/d) female mice showed a subfertility phenotype with reduced numbers and sizes of litters. These findings highlight that uterine development and regulation of estrogen receptor activities show a bimodal dependence on the gene dosage of REA. Optimal uterine development and functional activities require the normal gene dosage of REA, with partial or complete deletion resulting in hyperresponsiveness or underresponsiveness to hormone and subfertility or infertility, respectively.
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Affiliation(s)
- Sunghee Park
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 524 Burrill Hall, 407 South Goodwin Avenue, Urbana, Illinois 61801-3704, USA
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28
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Stratmann A, Haendler B. Histone demethylation and steroid receptor function in cancer. Mol Cell Endocrinol 2012; 348:12-20. [PMID: 21958694 DOI: 10.1016/j.mce.2011.09.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 09/05/2011] [Accepted: 09/13/2011] [Indexed: 10/17/2022]
Abstract
Steroid receptors recruit various cofactors to form multi-protein complexes which locally alter chromatin structure and control DNA accessibility in order to regulate gene transcription. Some of these factors are enzymes that add or remove histone marks in the vicinity of regulatory regions of target genes. Numerous histone modifications added by specific writer enzymes and removed by eraser enzymes have been identified. Histone methylation is a modification with a complex outcome, as it can lead to gene activation or repression, depending on the modified residue and the context. Methylation marks are added by different enzyme families displaying exquisite substrate specificity. Lysine methylation is reversible and two different demethylase families have been identified in humans, the Jumonji C and the lysine-specific demethylase families. A regulatory role of histone demethylases in fine-tuning the function of steroid receptors, especially the androgen receptor and estrogen receptor, has emerged in recent years. This is mostly inferred from in vitro studies, but more recently first in vivo data have further supported this concept. This and the deregulated expression observed for several histone demethylases suggest a role in tumours such as prostate and breast cancer.
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Affiliation(s)
- Antje Stratmann
- Therapeutic Research Group Oncology/Gynecological Therapies and Global Biomarker, Bayer Pharma AG, Bayer HealthCare, D-13342 Berlin, Germany
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Li KK, Luo C, Wang D, Jiang H, Zheng YG. Chemical and biochemical approaches in the study of histone methylation and demethylation. Med Res Rev 2010. [DOI: 10.1002/med.20228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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S-adenosylhomocysteine hydrolase inhibition by 3-deazaneplanocin A analogues induces anti-cancer effects in breast cancer cell lines and synergy with both histone deacetylase and HER2 inhibition. Breast Cancer Res Treat 2010; 127:109-19. [DOI: 10.1007/s10549-010-0982-0] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Accepted: 06/03/2010] [Indexed: 12/12/2022]
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Gieni RS, Hendzel MJ. Polycomb group protein gene silencing, non-coding RNA, stem cells, and cancer. Biochem Cell Biol 2010; 87:711-46. [PMID: 19898523 DOI: 10.1139/o09-057] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epigenetic programming is an important facet of biology, controlling gene expression patterns and the choice between developmental pathways. The Polycomb group proteins (PcGs) silence gene expression, allowing cells to both acquire and maintain identity. PcG silencing is important for stemness, X chromosome inactivation (XCI), genomic imprinting, and the abnormally silenced genes in cancers. Stem and cancer cells commonly share gene expression patterns, regulatory mechanisms, and signalling pathways. Many microRNA species have oncogenic or tumor suppressor activity, and disruptions in these networks are common in cancer; however, long non-coding (nc)RNA species are also important. Many of these directly guide PcG deposition and gene silencing at the HOX locus, during XCI, and in examples of genomic imprinting. Since inappropriate HOX expression and loss of genomic imprinting are hallmarks of cancer, disruption of long ncRNA-mediated PcG silencing likely has a role in oncogenesis. Aberrant silencing of coding and non-coding loci is critical for both the genesis and progression of cancers. In addition, PcGs are commonly abnormally overexpressed years prior to cancer pathology, making early PcG targeted therapy an option to reverse tumor formation, someday replacing the blunt instrument of eradication in the cancer therapy arsenal.
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Affiliation(s)
- Randall S Gieni
- Cross Cancer Institute and Department of Oncology, Faculty of Medicine, University of Alberta, Edmonton, AB T6G1Z2, Canada
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Godmann M, Lambrot R, Kimmins S. The dynamic epigenetic program in male germ cells: Its role in spermatogenesis, testis cancer, and its response to the environment. Microsc Res Tech 2009; 72:603-19. [PMID: 19319879 DOI: 10.1002/jemt.20715] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Spermatogenesis is a truly remarkable process that requires exquisite control and synchronization of germ cell development. It is prone to frequent error, as paternal infertility contributes to 30-50% of all infertility cases; yet, in many cases, the mechanisms underlying its causes are unknown. Strikingly, aberrant epigenetic profiles, in the form of anomalous DNA and histone modifications, are characteristic of cancerous testis cells. Germ cell development is a critical period during which epigenetic patterns are established and maintained. The progression from diploid spermatogonia to haploid spermatozoa involves stage- and testis-specific gene expression, mitotic and meiotic division, and the histone-protamine transition. All are postulated to engender unique epigenetic controls. In support of this idea are the findings that mouse models with gene deletions for epigenetic modifiers have severely compromised fertility. Underscoring the importance of understanding how epigenetic marks are set and interpreted is evidence that abnormal epigenetic programming of gametes and embryos contributes to heritable instabilities in subsequent generations. Numerous studies have documented the existence of transgenerational consequences of maternal nutrition, or other environmental exposures, but it is only now recognized that there are sex-specific male-line transgenerational responses in humans and other species. Epigenetic events in the testis have just begun to be studied. New work on the function of specific histone modifications, chromatin modifiers, DNA methylation, and the impact of the environment on developing sperm suggests that the correct setting of the epigenome is required for male reproductive health and the prevention of paternal disease transmission.
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Affiliation(s)
- Maren Godmann
- Department of Animal Science, McGill University, Montreal H9X3V9 Canada
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Stewart MD, Wong J. Nuclear receptor repression: regulatory mechanisms and physiological implications. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2009; 87:235-59. [PMID: 20374706 DOI: 10.1016/s1877-1173(09)87007-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The ability to associate with corepressors and to inhibit transcription is an intrinsic property of most members of the nuclear receptor (NR) superfamily. NRs induce transcriptional repression by recruiting multiprotein corepressor complexes. Nuclear receptor corepressor (NCoR) and silencing mediator of retinoic and thyroid receptors (SMRT) are the most well characterized corepressor complexes and mediate repression for virtually all NRs. In turn, corepressor complexes repress transcription because they either contain or associate with chromatin modifying enzymes. These include histone deacetylases, histone H3K4 demethylases, histone H3K9 or H3K27 methyltransferases, and ATP-dependent chromatin remodeling factors. Two types of NR-interacting corepressors exist. Ligand-independent corepressors, like NCoR/SMRT, bind to unliganded or antagonist-bound NRs, whereas ligand-dependent corepressors (LCoRs) associate with NRs in the presence of agonist. Therefore, LCoRs may serve to attenuate NR-mediated transcriptional activation. Somewhat unexpectedly, classical coactivators may also function as "corepressors" to mediate repression by agonist-bound NRs. In this chapter, we will discuss the various modes and mechanisms of repression by NRs as well as discuss the known physiological functions of NR-mediated repression.
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Affiliation(s)
- M David Stewart
- Department of Genetics, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
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Wu SC, Zhang Y. Minireview: role of protein methylation and demethylation in nuclear hormone signaling. Mol Endocrinol 2009; 23:1323-34. [PMID: 19407220 DOI: 10.1210/me.2009-0131] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Nuclear hormone receptors (NRs) are transcription factors responsible for mediating the biological effects of hormones during development, metabolism, and homeostasis. Induction of NR target genes is accomplished through the assembly of hormone-bound NR complexes at target promoters and coincides with changes in histone modifications that promote transcription. Some coactivators and corepressors of NR can enhance or inhibit NR function by covalently modifying histones. One such modification is methylation, which plays important roles in transcriptional regulation. Histone methylation is catalyzed by histone methyltransferases and reversed by histone demethylases. Recent studies have uncovered the importance of these enzymes in the regulation of NR target genes. In addition to histones, these enzymes have nonhistone substrates and can methylate and demethylate NRs and coregulatory proteins in order to modulate their function. This review discusses recent progress in our understanding of the role of methylation and demethylation of histones, NRs, and their coregulators in NR-mediated transcription.
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Affiliation(s)
- Susan C Wu
- Howard Hughes Medical Institute, Department of Biochemistry, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7295, USA
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Pietersen AM, Horlings HM, Hauptmann M, Langerød A, Ajouaou A, Cornelissen-Steijger P, Wessels LF, Jonkers J, van de Vijver MJ, van Lohuizen M. EZH2 and BMI1 inversely correlate with prognosis and TP53 mutation in breast cancer. Breast Cancer Res 2008; 10:R109. [PMID: 19099573 PMCID: PMC2656906 DOI: 10.1186/bcr2214] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 11/24/2008] [Accepted: 12/19/2008] [Indexed: 11/29/2022] Open
Abstract
Introduction PolycombGroup (PcG) proteins maintain gene repression through histone modifications and have been implicated in stem cell regulation and cancer. EZH2 is part of Polycomb Repressive Complex 2 (PRC2) and trimethylates H3K27. This histone mark recruits the BMI1-containing PRC1 that silences the genes marked by PRC2. Based on their role in stem cells, EZH2 and BMI1 have been predicted to contribute to a poor outcome for cancer patients. Methods We have analysed the expression of EZH2 and BMI1 in a well-characterised dataset of 295 human breast cancer samples. Results Interestingly, although EZH2 overexpression correlates with a poor prognosis in breast cancer, BMI1 overexpression correlates with a good outcome. Although this may reflect transformation of different cell types, we also observed a functional difference. The PcG-target genes INK4A and ARF are not expressed in tumours with high BMI1, but they are expressed in tumours with EZH2 overexpression. ARF expression results in tumour protein P53 (TP53) activation, and we found a significantly higher proportion of TP53 mutations in tumours with high EZH2. This may explain why tumours with high EZH2 respond poorly to therapy, in contrast to tumours with high BMI1. Conclusions Overall, our data highlight that whereas EZH2 and BMI1 may function in a 'linear' pathway in normal development, their overexpression has different functional consequences for breast tumourigenesis.
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Affiliation(s)
- Alexandra M Pietersen
- Division of Molecular Genetics, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam, 1066X, The Netherlands
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Zheng YG, Wu J, Chen Z, Goodman M. Chemical regulation of epigenetic modifications: opportunities for new cancer therapy. Med Res Rev 2008; 28:645-87. [PMID: 18271058 DOI: 10.1002/med.20120] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Epigenetics is concerned about heritable changes in gene expression without alteration of the coding sequence. Epigenetic modification of chromatin includes methylation of genomic DNA as well as post-translational modification of chromatin-associated proteins, in particular, histones. The spectrum of histone and non-histone modifications ranges from the addition of relatively small groups such as methyl, acetyl and phosphoryl groups to the attachment of larger moieties such as poly(ADP-ribose) and small proteins ubiquitin or small ubiquitin-like modifier (SUMO). The combinatorial nature of DNA methylation and histone modifications constitutes a significant pathway of epigenetic regulation and considerably extends the information potential of the genetic code. Chromatin modification has emerged as a new fundamental mechanism for gene transcriptional activity control associated with many cellular processes like proliferation, growth, and differentiation. Also it is increasingly recognized that epigenetic modifications constitute important regulatory mechanisms for the pathogenesis of malignant transformations. We review here the recent progress in the development of chemical inhibitors/activators that target different chromatin modifying enzymes. Such potent natural or synthetic modulators can be utilized to establish the quantitative contributions of epigenetic modifications in DNA regulated pathways including transcription, replication, recombination and repair, as well as provide leads for developing new cancer therapeutics.
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Affiliation(s)
- Yujun George Zheng
- Department of Chemistry, Georgia State University, PO Box 4098, Atlanta, Georgia 30302-4098, USA.
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