301
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Zhang B, Xing X, Li J, Lowdon RF, Zhou Y, Lin N, Zhang B, Sundaram V, Chiappinelli KB, Hagemann IS, Mutch DG, Goodfellow PJ, Wang T. Comparative DNA methylome analysis of endometrial carcinoma reveals complex and distinct deregulation of cancer promoters and enhancers. BMC Genomics 2014; 15:868. [PMID: 25286960 PMCID: PMC4198682 DOI: 10.1186/1471-2164-15-868] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 09/24/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Aberrant DNA methylation is a hallmark of many cancers. Classically there are two types of endometrial cancer, endometrioid adenocarcinoma (EAC), or Type I, and uterine papillary serous carcinoma (UPSC), or Type II. However, the whole genome DNA methylation changes in these two classical types of endometrial cancer is still unknown. RESULTS Here we described complete genome-wide DNA methylome maps of EAC, UPSC, and normal endometrium by applying a combined strategy of methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylation-sensitive restriction enzyme digestion sequencing (MRE-seq). We discovered distinct genome-wide DNA methylation patterns in EAC and UPSC: 27,009 and 15,676 recurrent differentially methylated regions (DMRs) were identified respectively, compared with normal endometrium. Over 80% of DMRs were in intergenic and intronic regions. The majority of these DMRs were not interrogated on the commonly used Infinium 450K array platform. Large-scale demethylation of chromosome X was detected in UPSC, accompanied by decreased XIST expression. Importantly, we discovered that the majority of the DMRs harbored promoter or enhancer functions and are specifically associated with genes related to uterine development and disease. Among these, abnormal methylation of transposable elements (TEs) may provide a novel mechanism to deregulate normal endometrium-specific enhancers derived from specific TEs. CONCLUSIONS DNA methylation changes are an important signature of endometrial cancer and regulate gene expression by affecting not only proximal promoters but also distal enhancers.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Aldehyde Dehydrogenase 1 Family
- Carcinoma, Papillary/genetics
- Carcinoma, Papillary/metabolism
- Chromosomes, Human, X
- CpG Islands
- DNA (Cytosine-5-)-Methyltransferases/genetics
- DNA (Cytosine-5-)-Methyltransferases/metabolism
- DNA Methylation
- DNA Transposable Elements/genetics
- Endometrial Neoplasms/genetics
- Endometrial Neoplasms/physiopathology
- Enhancer Elements, Genetic/genetics
- Female
- Humans
- Kruppel-Like Factor 4
- Kruppel-Like Transcription Factors/genetics
- MutL Protein Homolog 1
- Nuclear Proteins/genetics
- Polymorphism, Single Nucleotide
- Promoter Regions, Genetic/genetics
- RNA, Long Noncoding/genetics
- Retinal Dehydrogenase/genetics
- Sequence Analysis, DNA
- Uterine Neoplasms/genetics
- Uterine Neoplasms/physiopathology
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Affiliation(s)
- Bo Zhang
- />Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108 USA
| | - XiaoYun Xing
- />Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108 USA
| | - Jing Li
- />Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108 USA
- />Shanghai International Joint Cancer Institute, The Second Military Medical University, Shanghai, 200433 P. R. China
| | - Rebecca F Lowdon
- />Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108 USA
| | - Yan Zhou
- />Key Laboratory for Applied Statistics of MOE, School of Mathematics and Statistics, Northeast Normal University, Changchun, Jilin Province 130024 P. R. China
| | - Nan Lin
- />Department of Mathematics and Division of Biostatistics, Washington University in Saint Louis, Saint Louis, MO 63130 USA
| | - Baoxue Zhang
- />Key Laboratory for Applied Statistics of MOE, School of Mathematics and Statistics, Northeast Normal University, Changchun, Jilin Province 130024 P. R. China
| | - Vasavi Sundaram
- />Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108 USA
| | - Katherine B Chiappinelli
- />Department of Oncology, Sidney Kimmel Cancer Center, Johns Hopkins University, Baltimore, MD 21231 USA
| | - Ian S Hagemann
- />Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - David G Mutch
- />Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Washington University School of Medicine, St Louis, MO 63124 USA
| | - Paul J Goodfellow
- />The Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210 USA
| | - Ting Wang
- />Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO 63108 USA
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302
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Du W, Elemento O. Cancer systems biology: embracing complexity to develop better anticancer therapeutic strategies. Oncogene 2014; 34:3215-25. [PMID: 25220419 DOI: 10.1038/onc.2014.291] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/11/2014] [Accepted: 08/11/2014] [Indexed: 12/20/2022]
Abstract
The transformation of normal cells into cancer cells and maintenance of the malignant state and phenotypes are associated with genetic and epigenetic deregulations, altered cellular signaling responses and aberrant interactions with the microenvironment. These alterations are constantly evolving as tumor cells face changing selective pressures induced by the cells themselves, the microenvironment and drug treatments. Tumors are also complex ecosystems where different, sometime heterogeneous, subclonal tumor populations and a variety of nontumor cells coexist in a constantly evolving manner. The interactions between molecules and between cells that arise as a result of these alterations and ecosystems are even more complex. The cancer research community is increasingly embracing this complexity and adopting a combination of systems biology methods and integrated analyses to understand and predictively model the activity of cancer cells. Systems biology approaches are helping to understand the mechanisms of tumor progression and design more effective cancer therapies. These approaches work in tandem with rapid technological advancements that enable data acquisition on a broader scale, with finer accuracy, higher dimensionality and higher throughput than ever. Using such data, computational and mathematical models help identify key deregulated functions and processes, establish predictive biomarkers and optimize therapeutic strategies. Moving forward, implementing patient-specific computational and mathematical models of cancer will significantly improve the specificity and efficacy of targeted therapy, and will accelerate the adoption of personalized and precision cancer medicine.
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Affiliation(s)
- W Du
- Laboratory of Cancer Systems Biology, Sandra and Edward Meyer Cancer Center, Department of Physiology and Biophysics, Institute for Computational Biomedicine and Institute for Precision Medicine, Weill Cornell Medical College, New York, NY, USA
| | - O Elemento
- Laboratory of Cancer Systems Biology, Sandra and Edward Meyer Cancer Center, Department of Physiology and Biophysics, Institute for Computational Biomedicine and Institute for Precision Medicine, Weill Cornell Medical College, New York, NY, USA
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303
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Lund K, Cole JJ, VanderKraats ND, McBryan T, Pchelintsev NA, Clark W, Copland M, Edwards JR, Adams PD. DNMT inhibitors reverse a specific signature of aberrant promoter DNA methylation and associated gene silencing in AML. Genome Biol 2014; 15:406. [PMID: 25315154 PMCID: PMC4165364 DOI: 10.1186/s13059-014-0406-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 07/09/2014] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) are neoplastic disorders of hematopoietic stem cells. DNA methyltransferase inhibitors, 5-azacytidine and 5-aza-2'-deoxycytidine (decitabine), benefit some MDS/AML patients. However, the role of DNA methyltransferase inhibitor-induced DNA hypomethylation in regulation of gene expression in AML is unclear. RESULTS We compared the effects of 5-azacytidine on DNA methylation and gene expression using whole-genome single-nucleotide bisulfite-sequencing and RNA-sequencing in OCI-AML3 cells. For data analysis, we used an approach recently developed for discovery of differential patterns of DNA methylation associated with changes in gene expression, that is tailored to single-nucleotide bisulfite-sequencing data (Washington University Interpolated Methylation Signatures). Using this approach, we find that a subset of genes upregulated by 5-azacytidine are characterized by 5-azacytidine-induced signature methylation loss flanking the transcription start site. Many of these genes show increased methylation and decreased expression in OCI-AML3 cells compared to normal hematopoietic stem and progenitor cells. Moreover, these genes are preferentially upregulated by decitabine in human primary AML blasts, and control cell proliferation, death, and development. CONCLUSIONS Our approach identifies a set of genes whose methylation and silencing in AML is reversed by DNA methyltransferase inhibitors. These genes are good candidates for direct regulation by DNA methyltransferase inhibitors, and their reactivation by DNA methyltransferase inhibitors may contribute to therapeutic activity.
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Affiliation(s)
- Kirstin Lund
- />Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1BD UK
- />Beatson Institute for Cancer Research, Glasgow, G61 1BD UK
- />Paul O’Gorman Leukemia Research Centre, Glasgow, G12 0ZD UK
| | - John J Cole
- />Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1BD UK
- />Beatson Institute for Cancer Research, Glasgow, G61 1BD UK
| | - Nathan D VanderKraats
- />Center for Pharmacogenomics, Washington University School of Medicine, St Louis, MO 63110 USA
| | - Tony McBryan
- />Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1BD UK
- />Beatson Institute for Cancer Research, Glasgow, G61 1BD UK
| | - Nikolay A Pchelintsev
- />Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1BD UK
- />Beatson Institute for Cancer Research, Glasgow, G61 1BD UK
| | - William Clark
- />Beatson Institute for Cancer Research, Glasgow, G61 1BD UK
| | - Mhairi Copland
- />Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1BD UK
- />Paul O’Gorman Leukemia Research Centre, Glasgow, G12 0ZD UK
| | - John R Edwards
- />Center for Pharmacogenomics, Washington University School of Medicine, St Louis, MO 63110 USA
| | - Peter D Adams
- />Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1BD UK
- />Beatson Institute for Cancer Research, Glasgow, G61 1BD UK
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304
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Abstract
The comparison of DNA methylation patterns across cancer types (pan-cancer methylome analyses) has revealed distinct subgroups of tumors that share similar methylation patterns. Integration of these data with the wealth of information derived from cancer genome profiling studies performed by large international consortia has provided novel insights into the cellular aberrations that contribute to cancer development. There is evidence that genetic mutations in epigenetic regulators (such as DNMT3, IDH1/2 or H3.3) mediate or contribute to these patterns, although a unifying molecular mechanism underlying the global alterations of DNA methylation has largely been elusive. Knowledge gained from pan-cancer methylome analyses will aid the development of diagnostic and prognostic biomarkers, improve patient stratification and the discovery of novel druggable targets for therapy, and will generate hypotheses for innovative clinical trial designs based on methylation subgroups rather than on cancer subtypes. In this review, we discuss recent advances in the global profiling of tumor genomes for aberrant DNA methylation and the integration of these data with cancer genome profiling data, highlight potential mechanisms leading to different methylation subgroups, and show how this information can be used in basic research and for translational applications. A remaining challenge is to experimentally prove the functional link between observed pan-cancer methylation patterns, the associated genetic aberrations, and their relevance for the development of cancer.
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Affiliation(s)
- Tania Witte
- Division of Epigenomics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heid elberg, Germany
| | - Christoph Plass
- Division of Epigenomics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heid elberg, Germany
| | - Clarissa Gerhauser
- Division of Epigenomics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heid elberg, Germany
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305
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Timp W, Bravo HC, McDonald OG, Goggins M, Umbricht C, Zeiger M, Feinberg AP, Irizarry RA. Large hypomethylated blocks as a universal defining epigenetic alteration in human solid tumors. Genome Med 2014; 6:61. [PMID: 25191524 PMCID: PMC4154522 DOI: 10.1186/s13073-014-0061-y] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/12/2014] [Indexed: 01/30/2023] Open
Abstract
Background One of the most provocative recent observations in cancer epigenetics is the discovery of large hypomethylated blocks, including single copy genes, in colorectal cancer, that correspond in location to heterochromatic LOCKs (large organized chromatin lysine-modifications) and LADs (lamin-associated domains). Methods Here we performed a comprehensive genome-scale analysis of 10 breast, 28 colon, nine lung, 38 thyroid, 18 pancreas cancers, and five pancreas neuroendocrine tumors as well as matched normal tissue from most of these cases, as well as 51 premalignant lesions. We used a new statistical approach that allows the identification of large hypomethylated blocks on the Illumina HumanMethylation450 BeadChip platform. Results We find that hypomethylated blocks are a universal feature of common solid human cancer, and that they occur at the earliest stage of premalignant tumors and progress through clinical stages of thyroid and colon cancer development. We also find that the disrupted CpG islands widely reported previously, including hypermethylated island bodies and hypomethylated shores, are enriched in hypomethylated blocks, with flattening of the methylation signal within and flanking the islands. Finally, we found that genes showing higher between individual gene expression variability are enriched within these hypomethylated blocks. Conclusion Thus hypomethylated blocks appear to be a universal defining epigenetic alteration in human cancer, at least for common solid tumors. Electronic supplementary material The online version of this article (doi:10.1186/s13073-014-0061-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Winston Timp
- Center for Epigenetics, Johns Hopkins University School of Medicine, Baltimore, MD USA ; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD USA ; Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Hector Corrada Bravo
- Center for Bioinformatics and Computational Biology, Department of Computer Science, University of Maryland, College Park, MD USA
| | - Oliver G McDonald
- Center for Epigenetics, Johns Hopkins University School of Medicine, Baltimore, MD USA ; Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Michael Goggins
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Chris Umbricht
- Departments of Surgery and Molecular Biology & Genetics, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Martha Zeiger
- Departments of Surgery and Molecular Biology & Genetics, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Andrew P Feinberg
- Center for Epigenetics, Johns Hopkins University School of Medicine, Baltimore, MD USA ; Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD USA ; Molecular Biology & Genetics, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Rafael A Irizarry
- Center for Epigenetics, Johns Hopkins University School of Medicine, Baltimore, MD USA ; Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA ; Department of Biostatistics and Computational Biology, Dana Farber Cancer Institute and Department of Biostatistics, Harvard School of Public Health, Boston, MA USA
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306
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Zheng X, Zhao Q, Wu HJ, Li W, Wang H, Meyer CA, Qin QA, Xu H, Zang C, Jiang P, Li F, Hou Y, He J, Wang J, Wang J, Zhang P, Zhang Y, Liu XS. MethylPurify: tumor purity deconvolution and differential methylation detection from single tumor DNA methylomes. Genome Biol 2014; 15:419. [PMID: 25103624 PMCID: PMC4165374 DOI: 10.1186/s13059-014-0419-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/07/2014] [Indexed: 12/14/2022] Open
Abstract
We propose a statistical algorithm MethylPurify that uses regions with bisulfite reads showing discordant methylation levels to infer tumor purity from tumor samples alone. MethylPurify can identify differentially methylated regions (DMRs) from individual tumor methylome samples, without genomic variation information or prior knowledge from other datasets. In simulations with mixed bisulfite reads from cancer and normal cell lines, MethylPurify correctly inferred tumor purity and identified over 96% of the DMRs. From patient data, MethylPurify gave satisfactory DMR calls from tumor methylome samples alone, and revealed potential missed DMRs by tumor to normal comparison due to tumor heterogeneity.
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307
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Jeong M, Goodell MA. New answers to old questions from genome-wide maps of DNA methylation in hematopoietic cells. Exp Hematol 2014; 42:609-17. [PMID: 24993071 PMCID: PMC4137036 DOI: 10.1016/j.exphem.2014.04.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 04/17/2014] [Accepted: 04/22/2014] [Indexed: 01/10/2023]
Abstract
DNA methylation is a well-studied epigenetic modification essential for efficient cellular differentiation. Aberrant DNA methylation patterns are a characteristic feature of cancer, including myeloid malignancies such as acute myeloid leukemia. Recurrent mutations in DNA-modifying enzymes were identified in acute myeloid leukemia and linked to distinct DNA methylation signatures. In addition, discovery of Tet enzymes provided new mechanisms for the reversal of DNA methylation. Advances in base-resolution profiling of DNA methylation have enabled a more comprehensive understanding of the methylome landscape in the genome. This review will summarize and discuss the key questions in the function of DNA methylation in the hematopoietic system, including where and how DNA methylation regulates diverse biological processes in the genome as elucidated by recent studies.
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Affiliation(s)
- Mira Jeong
- Stem Cells and Regenerative Medicine Center, Department of Pediatrics and Molecular & Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Margaret A. Goodell
- Stem Cells and Regenerative Medicine Center, Department of Pediatrics and Molecular & Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
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308
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Easwaran H, Tsai HC, Baylin SB. Cancer epigenetics: tumor heterogeneity, plasticity of stem-like states, and drug resistance. Mol Cell 2014; 54:716-27. [PMID: 24905005 DOI: 10.1016/j.molcel.2014.05.015] [Citation(s) in RCA: 664] [Impact Index Per Article: 66.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The existence of subpopulations of cells in cancers with increased tumor-initiating capacities and self-renewal potential, often termed "cancer stem cells," is a much discussed and key area of cancer biology. Such cellular heterogeneity is very important because of its impact on therapy and especially states of treatment resistance. A major question is whether there is plasticity for evolution of these cell states during tumorigenesis that can involve movement between cell populations in a reversible fashion. In this review, we discuss the possible role of epigenetic abnormalities as well as genetic alterations in such dynamics and in the creation of cellular heterogeneity in cancers of all types.
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Affiliation(s)
- Hariharan Easwaran
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Hsing-Chen Tsai
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Stephen B Baylin
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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309
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Kagohara LT, Schussel JL, Subbannayya T, Sahasrabuddhe N, Lebron C, Brait M, Maldonado L, Valle BL, Pirini F, Jahuira M, Lopez J, Letelier P, Brebi-Mieville P, Ili C, Pandey A, Chatterjee A, Sidransky D, Guerrero-Preston R. Global and gene-specific DNA methylation pattern discriminates cholecystitis from gallbladder cancer patients in Chile. Future Oncol 2014; 11:233-49. [PMID: 25066711 PMCID: PMC4332836 DOI: 10.2217/fon.14.165] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM The aim of the study was to evaluate the use of global and gene-specific DNA methylation changes as potential biomarkers for gallbladder cancer (GBC) in a cohort from Chile. MATERIAL & METHODS DNA methylation was analyzed through an ELISA-based technique and quantitative methylation-specific PCR. RESULTS Global DNA Methylation Index (p = 0.02) and promoter methylation of SSBP2 (p = 0.01) and ESR1 (p = 0.05) were significantly different in GBC when compared with cholecystitis. Receiver curve operator analysis revealed promoter methylation of APC, CDKN2A, ESR1, PGP9.5 and SSBP2, together with the Global DNA Methylation Index, had 71% sensitivity, 95% specificity, a 0.97 area under the curve and a positive predictive value of 90%. CONCLUSION Global and gene-specific DNA methylation may be useful biomarkers for GBC clinical assessment.
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Affiliation(s)
- Luciane Tsukamoto Kagohara
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Juliana L Schussel
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
- Department of Oral Medicine, Post Graduation Program in Dentistry, Universidade Federal do Paraná, Curitiba, Brazil
| | | | | | - Cynthia Lebron
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Mariana Brait
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Leonel Maldonado
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Blanca L Valle
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Francesca Pirini
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Martha Jahuira
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Jaime Lopez
- Universidad de La Frontera, Facultad de Medicina, Departamento de Anatomía Patológica, Laboratorio Patología Molecular, BIOREN-CEGIN, Temuco, Chile
| | - Pablo Letelier
- Universidad de La Frontera, Facultad de Medicina, Departamento de Anatomía Patológica, Laboratorio Patología Molecular, BIOREN-CEGIN, Temuco, Chile
- Escuela Ciencias de la Salud, Universidad Católica de Temuco, Temuco, Chile
| | - Priscilla Brebi-Mieville
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
- Universidad de La Frontera, Facultad de Medicina, Departamento de Anatomía Patológica, Laboratorio Patología Molecular, BIOREN-CEGIN, Temuco, Chile
| | - Carmen Ili
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
- Universidad de La Frontera, Facultad de Medicina, Departamento de Anatomía Patológica, Laboratorio Patología Molecular, BIOREN-CEGIN, Temuco, Chile
| | - Akhilesh Pandey
- McKusick–Nathans Institute of Genetic Medicine, Baltimore, MD 21205, USA
- Department of Biological Chemistry, Baltimore, MD 21205, USA
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Aditi Chatterjee
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
- Institute of Bioinformatics, Whitefield, Bangalore 560066, Karnataka, India
| | - David Sidransky
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Rafael Guerrero-Preston
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- University of Puerto Rico School of Medicine, Department of Obstetrics & Gynecology, San Juan, Puerto Rico
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310
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Abstract
The aim of this review is to summarize an evolution of thinking about the epigenetic basis of human cancer, from the earliest studies of altered DNA methylation in cancer to the modern comprehensive epigenomic era. Converging data from epigenetic studies of primary cancers and from experimental studies of chromatin in development and epithelial-mesenchymal transition suggest a role for epigenetic stochasticity as a driving force of cancer, with Darwinian selection of tumour cells at the expense of the host. This increased epigenetic stochasticity appears to be mediated by large-scale changes in DNA methylation and chromatin in domains associated with the nuclear lamina. The implications for diagnosis include the potential to identify stochastically disrupted progenitor cells years before cancer develops, and to target drugs to epigenetic drivers of gene expression instability rather than to mean effects per se.
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Affiliation(s)
- A P Feinberg
- Center for Epigenetics and Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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311
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Quantitative epigenetic co-variation in CpG islands and co-regulation of developmental genes. Sci Rep 2014; 3:2576. [PMID: 23999385 PMCID: PMC6505400 DOI: 10.1038/srep02576] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 08/16/2013] [Indexed: 12/21/2022] Open
Abstract
The genome-wide variation of multiple epigenetic modifications in CpG islands (CGIs) and the interactions between them are of great interest. Here, we optimized an entropy-based strategy to quantify variation of epigenetic modifications and explored their interaction across mouse embryonic stem cells, neural precursor cells and brain. Our results showed that four epigenetic modifications (DNA methylation, H3K4me2, H3K4me3 and H3K27me3) of CGIs in the mouse genome undergo combinatorial variation during neuron differentiation. DNA methylation variation was positively correlated with H3K27me3 variation, and negatively correlated with H3K4me2/3 variation. We identified 5,194 CGIs differentially modified by epigenetic modifications (DEM-CGIs). Among them, the differentially DNA methylated CGIs overlapped significantly with the CGIs differentially modified by H3K27me3. Moreover, DEM-CGIs may contribute to co-regulation of related developmental genes including core transcription factors. Our entropy-based strategy provides an effective way of investigating dynamic cross-talk among epigenetic modifications in various biological processes at the macro scale.
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312
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HBx induces hypomethylation of distal intragenic CpG islands required for active expression of developmental regulators. Proc Natl Acad Sci U S A 2014; 111:9555-60. [PMID: 24941955 DOI: 10.1073/pnas.1400604111] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epigenetic alterations caused by viral oncoproteins are strong initiation factors for cancer development, but their mechanisms are largely unknown. To identify the epigenetic effects of viral hepatitis B virus X (HBx) that lead to hepatocellular carcinoma (HCC), we profiled the DNA methylomes of normal and HBx transgenic mouse liver. Intriguingly, severe hypomethylation of intragenic CpG islands (CGIs) was observed in HBx liver before the full development of HCC. Normally, these CGIs were highly methylated (mCGIs) by the DNMT3L complex and marked with epigenetic signatures associated with active expression, such as H3K36me3. Hypomethylation of mCGI was caused by the downregulation of Dnmt3L and Dnmt3a due to HBx bound to their promoters, along with HDAC1. These events lead to the downregulation of many developmental regulators that could facilitate tumorigenesis. Here we provide an intriguing epigenetic regulation mediated by mCGI that is required for cell differentiation and describe a previously unidentified epigenetic role for HBx in promoting HCC development.
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313
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Menafra R, Brinkman AB, Matarese F, Franci G, Bartels SJJ, Nguyen L, Shimbo T, Wade PA, Hubner NC, Stunnenberg HG. Genome-wide binding of MBD2 reveals strong preference for highly methylated loci. PLoS One 2014; 9:e99603. [PMID: 24927503 PMCID: PMC4057170 DOI: 10.1371/journal.pone.0099603] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 05/16/2014] [Indexed: 12/31/2022] Open
Abstract
MBD2 is a subunit of the NuRD complex that is postulated to mediate gene repression via recruitment of the complex to methylated DNA. In this study we adopted an MBD2 tagging-approach to study its genome wide binding characteristics. We show that in vivo MBD2 is mainly recruited to CpG island promoters that are highly methylated. Interestingly, MBD2 binds around 1 kb downstream of the transcription start site of a subset of ∼ 400 CpG island promoters that are characterized by the presence of active histone marks, RNA polymerase II (Pol2) and low to medium gene expression levels and H3K36me3 deposition. These tagged-MBD2 binding sites in MCF-7 show increased methylation in a cohort of primary breast cancers but not in normal breast samples, suggesting a putative role for MBD2 in breast cancer.
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Affiliation(s)
- Roberta Menafra
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Arie B. Brinkman
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Filomena Matarese
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Gianluigi Franci
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Stefanie J. J. Bartels
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Luan Nguyen
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Takashi Shimbo
- Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America
| | - Paul A. Wade
- Laboratory of Molecular Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America
| | - Nina C. Hubner
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Hendrik G. Stunnenberg
- Department of Molecular Biology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
- * E-mail:
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314
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Chuang TJ, Chiang TW. Impacts of pretranscriptional DNA methylation, transcriptional transcription factor, and posttranscriptional microRNA regulations on protein evolutionary rate. Genome Biol Evol 2014; 6:1530-41. [PMID: 24923326 PMCID: PMC4080426 DOI: 10.1093/gbe/evu124] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Gene expression is largely regulated by DNA methylation, transcription factor (TF), and
microRNA (miRNA) before, during, and after transcription, respectively. Although the
evolutionary effects of TF/miRNA regulations have been widely studied, evolutionary
analysis of simultaneously accounting for DNA methylation, TF, and miRNA regulations and
whether promoter methylation and gene body (coding regions) methylation have different
effects on the rate of gene evolution remain uninvestigated. Here, we compared
human–macaque and human–mouse protein evolutionary rates against
experimentally determined single base-resolution DNA methylation data, revealing that
promoter methylation level is positively correlated with protein evolutionary rates but
negatively correlated with TF/miRNA regulations, whereas the opposite was observed for
gene body methylation level. Our results showed that the relative importance of these
regulatory factors in determining the rate of mammalian protein evolution is as follows:
Promoter methylation ≈ miRNA regulation > gene body methylation > TF regulation,
and further indicated that promoter methylation and miRNA regulation have a significant
dependent effect on protein evolutionary rates. Although the mechanisms underlying
cooperation between DNA methylation and TFs/miRNAs in gene regulation remain unclear, our
study helps to not only illuminate the impact of these regulatory factors on mammalian
protein evolution but also their intricate interaction within gene regulatory
networks.
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Affiliation(s)
- Trees-Juen Chuang
- Division of Physical & Computational Genomics, Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Tai-Wei Chiang
- Division of Physical & Computational Genomics, Genomics Research Center, Academia Sinica, Taipei, Taiwan
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315
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Bjanesoy TE, Andreassen BK, Bratland E, Reiner A, Islam S, Husebye ES, Bakke M. Altered DNA methylation profile in Norwegian patients with Autoimmune Addison's Disease. Mol Immunol 2014; 59:208-16. [DOI: 10.1016/j.molimm.2014.02.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 02/21/2014] [Accepted: 02/25/2014] [Indexed: 12/13/2022]
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316
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Li Y, Li S, Chen J, Shao T, Jiang C, Wang Y, Chen H, Xu J, Li X. Comparative epigenetic analyses reveal distinct patterns of oncogenic pathways activation in breast cancer subtypes. Hum Mol Genet 2014; 23:5378-93. [DOI: 10.1093/hmg/ddu256] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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317
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Hovestadt V, Jones DTW, Picelli S, Wang W, Kool M, Northcott PA, Sultan M, Stachurski K, Ryzhova M, Warnatz HJ, Ralser M, Brun S, Bunt J, Jäger N, Kleinheinz K, Erkek S, Weber UD, Bartholomae CC, von Kalle C, Lawerenz C, Eils J, Koster J, Versteeg R, Milde T, Witt O, Schmidt S, Wolf S, Pietsch T, Rutkowski S, Scheurlen W, Taylor MD, Brors B, Felsberg J, Reifenberger G, Borkhardt A, Lehrach H, Wechsler-Reya RJ, Eils R, Yaspo ML, Landgraf P, Korshunov A, Zapatka M, Radlwimmer B, Pfister SM, Lichter P. Decoding the regulatory landscape of medulloblastoma using DNA methylation sequencing. Nature 2014; 510:537-41. [PMID: 24847876 DOI: 10.1038/nature13268] [Citation(s) in RCA: 319] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 03/20/2014] [Indexed: 02/08/2023]
Abstract
Epigenetic alterations, that is, disruption of DNA methylation and chromatin architecture, are now acknowledged as a universal feature of tumorigenesis. Medulloblastoma, a clinically challenging, malignant childhood brain tumour, is no exception. Despite much progress from recent genomics studies, with recurrent changes identified in each of the four distinct tumour subgroups (WNT-pathway-activated, SHH-pathway-activated, and the less-well-characterized Group 3 and Group 4), many cases still lack an obvious genetic driver. Here we present whole-genome bisulphite-sequencing data from thirty-four human and five murine tumours plus eight human and three murine normal controls, augmented with matched whole-genome, RNA and chromatin immunoprecipitation sequencing data. This comprehensive data set allowed us to decipher several features underlying the interplay between the genome, epigenome and transcriptome, and its effects on medulloblastoma pathophysiology. Most notable were highly prevalent regions of hypomethylation correlating with increased gene expression, extending tens of kilobases downstream of transcription start sites. Focal regions of low methylation linked to transcription-factor-binding sites shed light on differential transcriptional networks between subgroups, whereas increased methylation due to re-normalization of repressed chromatin in DNA methylation valleys was positively correlated with gene expression. Large, partially methylated domains affecting up to one-third of the genome showed increased mutation rates and gene silencing in a subgroup-specific fashion. Epigenetic alterations also affected novel medulloblastoma candidate genes (for example, LIN28B), resulting in alternative promoter usage and/or differential messenger RNA/microRNA expression. Analysis of mouse medulloblastoma and precursor-cell methylation demonstrated a somatic origin for many alterations. Our data provide insights into the epigenetic regulation of transcription and genome organization in medulloblastoma pathogenesis, which are probably also of importance in a wider developmental and disease context.
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Affiliation(s)
- Volker Hovestadt
- 1] Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2]
| | - David T W Jones
- 1] Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2]
| | - Simone Picelli
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Wei Wang
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Marcel Kool
- Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Paul A Northcott
- Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Marc Sultan
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, Berlin 14195, Germany
| | - Katharina Stachurski
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, Düsseldorf 40225, Germany
| | - Marina Ryzhova
- Department of Neuropathology, NN Burdenko Neurosurgical Institute, 4th Tverskaya-Yamskaya 16, Moscow 125047, Russia
| | - Hans-Jörg Warnatz
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, Berlin 14195, Germany
| | - Meryem Ralser
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, Berlin 14195, Germany
| | - Sonja Brun
- Tumor Initiation and Maintenance Program, National Cancer Institute (NCI)-Designated Cancer Center, Sanford-Burnham Medical Research Institute, 2880 Torrey Pines Scenic Drive, La Jolla, California 92037, USA
| | - Jens Bunt
- 1] Queensland Brain Institute, University of Queensland, QBI Building, St Lucia, Queensland 4072, Australia [2] Department of Oncogenomics, AMC, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, the Netherlands
| | - Natalie Jäger
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Kortine Kleinheinz
- 1] Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Serap Erkek
- 1] Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg 69117, Germany
| | - Ursula D Weber
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Cynthia C Bartholomae
- 1] Division of Translational Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 460, Heidelberg 69120, Germany
| | - Christof von Kalle
- 1] Division of Translational Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 460, Heidelberg 69120, Germany
| | - Chris Lawerenz
- Data Management Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Jürgen Eils
- Data Management Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Jan Koster
- Department of Oncogenomics, AMC, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, the Netherlands
| | - Rogier Versteeg
- Department of Oncogenomics, AMC, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, the Netherlands
| | - Till Milde
- 1] Department of Pediatric Oncology, Hematology & Immunology, Heidelberg University Hospital, Im Neuenheimer Feld 430, Heidelberg 69120, Germany [2] Clinical Cooperation Unit Pediatric Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Olaf Witt
- 1] Department of Pediatric Oncology, Hematology & Immunology, Heidelberg University Hospital, Im Neuenheimer Feld 430, Heidelberg 69120, Germany [2] Clinical Cooperation Unit Pediatric Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Sabine Schmidt
- Genomics and Proteomics Core Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Stephan Wolf
- Genomics and Proteomics Core Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Torsten Pietsch
- Department of Neuropathology, University of Bonn Medical Center, Sigmund-Freud-Strasse 25, Bonn 53105, Germany
| | - Stefan Rutkowski
- Department of Paediatric Haematology and Oncology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, Hamburg 20246, Germany
| | - Wolfram Scheurlen
- Cnopf'sche Kinderklinik, Nürnberg Children's Hospital, St.-Johannis-Mühlgasse 19, Nürnberg 90419, Germany
| | - Michael D Taylor
- 1] Program in Developmental and Stem Cell Biology, The Arthur and Sonia Labatt Brain Tumour Research Centre, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada [2] Division of Neurosurgery, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada [3] Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Benedikt Brors
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Jörg Felsberg
- 1] Department of Neuropathology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, Düsseldorf 40225, Germany [2] German Consortium for Translational Cancer Research (DKTK), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Guido Reifenberger
- 1] Department of Neuropathology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, Düsseldorf 40225, Germany [2] German Consortium for Translational Cancer Research (DKTK), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Arndt Borkhardt
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, Düsseldorf 40225, Germany
| | - Hans Lehrach
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, Berlin 14195, Germany
| | - Robert J Wechsler-Reya
- Tumor Initiation and Maintenance Program, National Cancer Institute (NCI)-Designated Cancer Center, Sanford-Burnham Medical Research Institute, 2880 Torrey Pines Scenic Drive, La Jolla, California 92037, USA
| | - Roland Eils
- 1] Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Institute of Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Heidelberg 69120, Germany [3] Bioquant Center, University of Heidelberg, Im Neuenheimer Feld 267, Heidelberg 69120, Germany [4] Heidelberg Center for Personalised Oncology (DKFZ-HIPO), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Marie-Laure Yaspo
- Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, Berlin 14195, Germany
| | - Pablo Landgraf
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, Düsseldorf 40225, Germany
| | - Andrey Korshunov
- 1] Department of Neuropathology, University of Heidelberg, Im Neuenheimer Feld 220, Heidelberg 69120, Germany [2] Clinical Cooperation Unit Neuropathology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 220-221, Heidelberg, 69120 Germany
| | - Marc Zapatka
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Bernhard Radlwimmer
- Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Stefan M Pfister
- 1] Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Department of Pediatric Oncology, Hematology & Immunology, Heidelberg University Hospital, Im Neuenheimer Feld 430, Heidelberg 69120, Germany
| | - Peter Lichter
- 1] Division of Molecular Genetics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany [2] Heidelberg Center for Personalised Oncology (DKFZ-HIPO), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
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318
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Nagarajan RP, Zhang B, Bell RJ, Johnson BE, Olshen AB, Sundaram V, Li D, Graham AE, Diaz A, Fouse SD, Smirnov I, Song J, Paris PL, Wang T, Costello JF. Recurrent epimutations activate gene body promoters in primary glioblastoma. Genome Res 2014; 24:761-74. [PMID: 24709822 PMCID: PMC4009606 DOI: 10.1101/gr.164707.113] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 02/05/2014] [Indexed: 01/09/2023]
Abstract
Aberrant DNA hypomethylation may play an important role in the growth rate of glioblastoma (GBM), but the functional impact on transcription remains poorly understood. We assayed the GBM methylome with MeDIP-seq and MRE-seq, adjusting for copy number differences, in a small set of non-glioma CpG island methylator phenotype (non-G-CIMP) primary tumors. Recurrent hypomethylated loci were enriched within a region of chromosome 5p15 that is specified as a cancer amplicon and also encompasses TERT, encoding telomerase reverse transcriptase, which plays a critical role in tumorigenesis. Overall, 76 gene body promoters were recurrently hypomethylated, including TERT and the oncogenes GLI3 and TP73. Recurring hypomethylation also affected previously unannotated alternative promoters, and luciferase reporter assays for three of four of these promoters confirmed strong promoter activity in GBM cells. Histone H3 lysine 4 trimethylation (H3K4me3) ChIP-seq on tissue from the GBMs uncovered peaks that coincide precisely with tumor-specific decrease of DNA methylation at 200 loci, 133 of which are in gene bodies. Detailed investigation of TP73 and TERT gene body hypomethylation demonstrated increased expression of corresponding alternate transcripts, which in TP73 encodes a truncated p73 protein with oncogenic function and in TERT encodes a putative reverse transcriptase-null protein. Our findings suggest that recurring gene body promoter hypomethylation events, along with histone H3K4 trimethylation, alter the transcriptional landscape of GBM through the activation of a limited number of normally silenced promoters within gene bodies, in at least one case leading to expression of an oncogenic protein.
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Affiliation(s)
- Raman P. Nagarajan
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Bo Zhang
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri 63108, USA
| | - Robert J.A. Bell
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Brett E. Johnson
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Adam B. Olshen
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Vasavi Sundaram
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri 63108, USA
| | - Daofeng Li
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri 63108, USA
| | - Ashley E. Graham
- Department of Microbiology and Immunology, University of California San Francisco, California 94143, USA
| | - Aaron Diaz
- Institute for Human Genetics, University of California San Francisco, California 94143, USA
| | - Shaun D. Fouse
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Ivan Smirnov
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Jun Song
- Institute for Human Genetics, University of California San Francisco, California 94143, USA
| | - Pamela L. Paris
- Department of Urology, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
| | - Ting Wang
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri 63108, USA
| | - Joseph F. Costello
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, California 94143, USA
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319
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Abstract
DNA methylation is one of the best characterized epigenetic modifications. In mammals it is involved in various biological processes including the silencing of transposable elements, regulation of gene expression, genomic imprinting, and X-chromosome inactivation. This article describes how DNA methylation serves as a cellular memory system and how it is dynamically regulated through the action of the DNA methyltransferase (DNMT) and ten eleven translocation (TET) enzymes. Its role in the regulation of gene expression, through its interplay with histone modifications, is also described, and its implication in human diseases discussed. The exciting areas of investigation that will likely become the focus of research in the coming years are outlined in the summary.
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Affiliation(s)
- En Li
- China Novartis Institutes for BioMedical Research, Pudong New Area, Shanghai 201203, China
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320
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Abstract
Genomic information is encoded on a wide range of distance scales, ranging from tens of base pairs to megabases. We developed a multiscale framework to analyze and visualize the information content of genomic signals. Different types of signals, such as GC content or DNA methylation, are characterized by distinct patterns of signal enrichment or depletion across scales spanning several orders of magnitude. These patterns are associated with a variety of genomic annotations, including genes, nuclear lamina associated domains, and repeat elements. By integrating the information across all scales, as compared to using any single scale, we demonstrate improved prediction of gene expression from Polymerase II chromatin immunoprecipitation sequencing (ChIP-seq) measurements and we observed that gene expression differences in colorectal cancer are not most strongly related to gene body methylation, but rather to methylation patterns that extend beyond the single-gene scale.
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321
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Characterization of human pseudogene-derived non-coding RNAs for functional potential. PLoS One 2014; 9:e93972. [PMID: 24699680 PMCID: PMC3974860 DOI: 10.1371/journal.pone.0093972] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/10/2014] [Indexed: 11/19/2022] Open
Abstract
Thousands of pseudogenes exist in the human genome and many are transcribed, but their functional potential remains elusive and understudied. To explore these issues systematically, we first developed a computational pipeline to identify transcribed pseudogenes from RNA-Seq data. Applying the pipeline to datasets from 16 distinct normal human tissues identified ∼ 3,000 pseudogenes that could produce non-coding RNAs in a manner of low abundance but high tissue specificity under normal physiological conditions. Cross-tissue comparison revealed that the transcriptional profiles of pseudogenes and their parent genes showed mostly positive correlations, suggesting that pseudogene transcription could have a positive effect on the expression of their parent genes, perhaps by functioning as competing endogenous RNAs (ceRNAs), as previously suggested and demonstrated with the PTEN pseudogene, PTENP1. Our analysis of the ENCODE project data also found many transcriptionally active pseudogenes in the GM12878 and K562 cell lines; moreover, it showed that many human pseudogenes produced small RNAs (sRNAs) and some pseudogene-derived sRNAs, especially those from antisense strands, exhibited evidence of interfering with gene expression. Further integrated analysis of transcriptomics and epigenomics data, however, demonstrated that trimethylation of histone 3 at lysine 9 (H3K9me3), a posttranslational modification typically associated with gene repression and heterochromatin, was enriched at many transcribed pseudogenes in a transcription-level dependent manner in the two cell lines. The H3K9me3 enrichment was more prominent in pseudogenes that produced sRNAs at pseudogene loci and their adjacent regions, an observation further supported by the co-enrichment of SETDB1 (a H3K9 methyltransferase), suggesting that pseudogene sRNAs may have a role in regional chromatin repression. Taken together, our comprehensive and systematic characterization of pseudogene transcription uncovers a complex picture of how pseudogene ncRNAs could influence gene and pseudogene expression, at both epigenetic and post-transcriptional levels.
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322
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From genomes to societies: a holistic view of determinants of human health. Curr Opin Biotechnol 2014; 28:134-42. [PMID: 24686286 DOI: 10.1016/j.copbio.2014.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 02/22/2014] [Accepted: 03/05/2014] [Indexed: 12/22/2022]
Abstract
Both biological and social sciences have identified contributing factors to human health. However, health outcomes are unlikely to equal a simple sum of these identified factors. This article makes an attempt to put together the information, methods, and technologies that relate to health outcomes from biological, behavioral, and social disciplines. Much of this information was obtained by controlling for the variations of the factors in 'other' disciplines. For example, genetic factors were controlled for in identifying the behavioral determinants of health. Looking forward, better understandings of health outcomes may require exploiting the interactions of health determinants that were identified from different disciplines. We propose the concept of 'systems health' studies, which take health outcomes as the outputs of a system, where the inputs and their interactions from multiple disciplines are considered.
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323
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Oakes CC, Claus R, Gu L, Assenov Y, Hüllein J, Zucknick M, Bieg M, Brocks D, Bogatyrova O, Schmidt CR, Rassenti L, Kipps TJ, Mertens D, Lichter P, Döhner H, Stilgenbauer S, Byrd JC, Zenz T, Plass C. Evolution of DNA methylation is linked to genetic aberrations in chronic lymphocytic leukemia. Cancer Discov 2014; 4:348-61. [PMID: 24356097 PMCID: PMC4134522 DOI: 10.1158/2159-8290.cd-13-0349] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Although clonal selection by genetic driver aberrations in cancer is well documented, the ability of epigenetic alterations to promote tumor evolution is undefined. We used 450k arrays and next-generation sequencing to evaluate intratumor heterogeneity and evolution of DNA methylation and genetic aberrations in chronic lymphocytic leukemia (CLL). CLL cases exhibit vast interpatient differences in intratumor methylation heterogeneity, with genetically clonal cases maintaining low methylation heterogeneity and up to 10% of total CpGs in a monoallelically methylated state. Increasing methylation heterogeneity correlates with advanced genetic subclonal complexity. Selection of novel DNA methylation patterns is observed only in cases that undergo genetic evolution, and independent genetic evolution is uncommon and is restricted to low-risk alterations. These results reveal that although evolution of DNA methylation occurs in high-risk, clinically progressive cases, positive selection of novel methylation patterns entails coevolution of genetic alteration(s) in CLL.
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MESH Headings
- Aged
- Chromosomes, Human
- CpG Islands
- DNA Methylation
- Disease Progression
- Epigenesis, Genetic
- Female
- Gene Expression Regulation, Leukemic
- Genetic Heterogeneity
- Genome, Human
- Genomic Instability
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Male
- Middle Aged
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Affiliation(s)
- Christopher C. Oakes
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Rainer Claus
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
- Department of Medicine, University of Freiburg Medical Center, Freiburg
| | - Lei Gu
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
- Division of Theoretical Bioinformatics, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Yassen Assenov
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Jennifer Hüllein
- Department of Translational Oncology, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Manuela Zucknick
- Division of Biostatistics, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Matthias Bieg
- Division of Theoretical Bioinformatics, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - David Brocks
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Olga Bogatyrova
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Christopher R. Schmidt
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
| | - Laura Rassenti
- Department of Medicine, University of California at San Diego Moores Cancer Center, La Jolla, California
| | - Thomas J. Kipps
- Department of Medicine, University of California at San Diego Moores Cancer Center, La Jolla, California
| | - Daniel Mertens
- Division of Molecular Genetics, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
- Department of Internal Medicine III, University of Ulm, Ulm
| | - Peter Lichter
- Division of Molecular Genetics, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
- The German Cancer Consortium, Germany
| | - Hartmut Döhner
- Department of Internal Medicine III, University of Ulm, Ulm
| | | | - John C. Byrd
- Division of Hematology, The Ohio State University, Columbus, Ohio
| | - Thorsten Zenz
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
- Department of Medicine V, University of Heidelberg, Heidelberg
| | - Christoph Plass
- Division of Epigenomics and Cancer Risk Factors, National Center for Tumor Diseases (NCT), The German Cancer Research Center (DKFZ)
- The German Cancer Consortium, Germany
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324
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Genome regulation at the peripheral zone: lamina associated domains in development and disease. Curr Opin Genet Dev 2014; 25:50-61. [PMID: 24556270 DOI: 10.1016/j.gde.2013.11.021] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 11/29/2013] [Indexed: 12/18/2022]
Abstract
The nuclear periphery has been implicated in gene regulation and it has been proposed that proximity to the nuclear lamina and inner nuclear membrane (INM) leads to gene repression. More recently, it appears that there is a correlation and interdependence between lamina associated domains (LADs), the epigenome and overall three-dimensional architecture of the genome. However, the mechanisms of such organization at the 'peripheral zone' and the functional significance of these associations are poorly understood. The role these domains play in development and disease is an active and exciting area of research, expanding our knowledge of how the three-dimensional (3D) genome is regulated.
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325
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Gaidatzis D, Burger L, Murr R, Lerch A, Dessus-Babus S, Schübeler D, Stadler MB. DNA sequence explains seemingly disordered methylation levels in partially methylated domains of Mammalian genomes. PLoS Genet 2014; 10:e1004143. [PMID: 24550741 PMCID: PMC3923675 DOI: 10.1371/journal.pgen.1004143] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 12/11/2013] [Indexed: 01/20/2023] Open
Abstract
For the most part metazoan genomes are highly methylated and harbor only small regions with low or absent methylation. In contrast, partially methylated domains (PMDs), recently discovered in a variety of cell lines and tissues, do not fit this paradigm as they show partial methylation for large portions (20%-40%) of the genome. While in PMDs methylation levels are reduced on average, we found that at single CpG resolution, they show extensive variability along the genome outside of CpG islands and DNase I hypersensitive sites (DHS). Methylation levels range from 0% to 100% in a roughly uniform fashion with only little similarity between neighboring CpGs. A comparison of various PMD-containing methylomes showed that these seemingly disordered states of methylation are strongly conserved across cell types for virtually every PMD. Comparative sequence analysis suggests that DNA sequence is a major determinant of these methylation states. This is further substantiated by a purely sequence based model which can predict 31% (R(2)) of the variation in methylation. The model revealed CpG density as the main driving feature promoting methylation, opposite to what has been shown for CpG islands, followed by various dinucleotides immediately flanking the CpG and a minor contribution from sequence preferences reflecting nucleosome positioning. Taken together we provide a reinterpretation for the nucleotide-specific methylation levels observed in PMDs, demonstrate their conservation across tissues and suggest that they are mainly determined by specific DNA sequence features.
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Affiliation(s)
- Dimos Gaidatzis
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- Swiss Institute of Bioinformatics, Basel, Switzerland
- * E-mail:
| | - Lukas Burger
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Rabih Murr
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Anita Lerch
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | | | - Dirk Schübeler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- Faculty of Science, University of Basel, Basel, Switzerland
| | - Michael B. Stadler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- Swiss Institute of Bioinformatics, Basel, Switzerland
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326
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Abstract
Comprehensive sequencing of benign and malignant tumors has recently uncovered new driver mutations in childhood tumors. A new report now describes frequent histone H3.3 alterations in chondroblastoma and giant cell tumor of bone, emphasizing the importance of this histone variant in pediatric cancers.
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Affiliation(s)
- Anders M Lindroth
- Division of Epigenomics and Cancer Risk Factors at the German Cancer Research Center (DKFZ), Heidelberg, Germany
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327
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Millán-Ariño L, Islam ABMMK, Izquierdo-Bouldstridge A, Mayor R, Terme JM, Luque N, Sancho M, López-Bigas N, Jordan A. Mapping of six somatic linker histone H1 variants in human breast cancer cells uncovers specific features of H1.2. Nucleic Acids Res 2014; 42:4474-93. [PMID: 24476918 PMCID: PMC3985652 DOI: 10.1093/nar/gku079] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Seven linker histone H1 variants are present in human somatic cells with distinct prevalence across cell types. Despite being key structural components of chromatin, it is not known whether the different variants have specific roles in the regulation of nuclear processes or are differentially distributed throughout the genome. Using variant-specific antibodies to H1 and hemagglutinin (HA)-tagged recombinant H1 variants expressed in breast cancer cells, we have investigated the distribution of six H1 variants in promoters and genome-wide. H1 is depleted at promoters depending on its transcriptional status and differs between variants. Notably, H1.2 is less abundant than other variants at the transcription start sites of inactive genes, and promoters enriched in H1.2 are different from those enriched in other variants and tend to be repressed. Additionally, H1.2 is enriched at chromosomal domains characterized by low guanine–cytosine (GC) content and is associated with lamina-associated domains. Meanwhile, other variants are associated with higher GC content, CpG islands and gene-rich domains. For instance, H1.0 and H1X are enriched at gene-rich chromosomes, whereas H1.2 is depleted. In short, histone H1 is not uniformly distributed along the genome and there are differences between variants, H1.2 being the one showing the most specific pattern and strongest correlation with low gene expression.
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Affiliation(s)
- Lluís Millán-Ariño
- Department of Molecular Genomics, Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Barcelona, E-08028 Spain, Research Programme on Biomedical Informatics, Universitat Pompeu Fabra, Barcelona, E-08003 Spain, Department of Genetic Engineering, Biotechnology, University of Dhaka, Dhaka-1000, Bangladesh, Centro de Investigación Príncipe Felipe, Valencia, E-46012 Spain and Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, E-08010 Spain
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328
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Saito Y, Tsuji J, Mituyama T. Bisulfighter: accurate detection of methylated cytosines and differentially methylated regions. Nucleic Acids Res 2014; 42:e45. [PMID: 24423865 PMCID: PMC3973284 DOI: 10.1093/nar/gkt1373] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Analysis of bisulfite sequencing data usually requires two tasks: to call methylated cytosines (mCs) in a sample, and to detect differentially methylated regions (DMRs) between paired samples. Although numerous tools have been proposed for mC calling, methods for DMR detection have been largely limited. Here, we present Bisulfighter, a new software package for detecting mCs and DMRs from bisulfite sequencing data. Bisulfighter combines the LAST alignment tool for mC calling, and a novel framework for DMR detection based on hidden Markov models (HMMs). Unlike previous attempts that depend on empirical parameters, Bisulfighter can use the expectation-maximization algorithm for HMMs to adjust parameters for each data set. We conduct extensive experiments in which accuracy of mC calling and DMR detection is evaluated on simulated data with various mC contexts, read qualities, sequencing depths and DMR lengths, as well as on real data from a wide range of biological processes. We demonstrate that Bisulfighter consistently achieves better accuracy than other published tools, providing greater sensitivity for mCs with fewer false positives, more precise estimates of mC levels, more exact locations of DMRs and better agreement of DMRs with gene expression and DNase I hypersensitivity. The source code is available at http://epigenome.cbrc.jp/bisulfighter.
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Affiliation(s)
- Yutaka Saito
- Computational Biology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan, Japan Science and Technology Agency, CREST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan and Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA
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329
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Heyn H, Méndez-González J, Esteller M. Epigenetic profiling joins personalized cancer medicine. Expert Rev Mol Diagn 2014; 13:473-9. [DOI: 10.1586/erm.13.36] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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330
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Fleischer T, Edvardsen H, Solvang HK, Daviaud C, Naume B, Børresen-Dale AL, Kristensen VN, Tost J. Integrated analysis of high-resolution DNA methylation profiles, gene expression, germline genotypes and clinical end points in breast cancer patients. Int J Cancer 2014; 134:2615-25. [PMID: 24395279 DOI: 10.1002/ijc.28606] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 09/06/2013] [Accepted: 10/24/2013] [Indexed: 12/13/2022]
Abstract
Breast cancer is a heterogeneous disease for which alterations in DNA methylation patterns have been shown to be of biological and clinical importance. Here we report on the integrated analysis of molecular alterations including the methylation status of 27 gene promoters analyzed by highly quantitative pyrosequencing, and the association to gene expression, germline genotype and clinical parameters including survival. Breast cancer specific deregulation of DNA methylation (both hyper- and hypomethylation) was found in twenty genes including ACVR1, OGG1, IL8 and TFF1. The methylation level in the promoter regions was significantly negatively correlated to gene expression for twelve genes (such as MST1R, ST6GAL1 and TFF1) indicating that a gain of aberrant methylation (hypermethylation) inhibits gene expression. Multiple associations between molecular and clinical parameters were identified, and multivariate statistical analysis demonstrated that methylation was more strongly associated to clinical parameters than gene expression for the investigated genes. The methylation level of BCAP31 and OGG1 showed significant association to survival, and these associations were validated in a larger patient cohort (The Cancer Genome Atlas). Our study provides evidence for the promise of DNA methylation alterations for clinical applications.
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Affiliation(s)
- Thomas Fleischer
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital Radiumhospitalet, Oslo, Norway; The K.G. Jebsen Center for Breast Cancer Research, Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, Norway
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331
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Weisenberger DJ. Characterizing DNA methylation alterations from The Cancer Genome Atlas. J Clin Invest 2014; 124:17-23. [PMID: 24382385 DOI: 10.1172/jci69740] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Cancer Genome Atlas (TCGA) Research Network is an ambitious multi-institutional consortium effort aimed at characterizing sequence, copy number, gene (mRNA) expression, microRNA expression, and DNA methylation alterations in 30 cancer types. TCGA data have become an extraordinary resource for basic, translational, and clinical researchers and have the potential to shape cancer diagnostic and treatment strategies. DNA methylation changes are integral to all aspects of cancer genomics and have been shown to have important associations with gene expression, sequence, and copy number changes. This Review highlights the knowledge gained from DNA methylation alterations in human cancers from TCGA.
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332
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O'Donnell AH, Edwards JR, Rollins RA, Vander Kraats ND, Su T, Hibshoosh HH, Bestor TH. Methylation Abnormalities in Mammary Carcinoma: The Methylation Suicide Hypothesis. ACTA ACUST UNITED AC 2014; 5:1311-1324. [PMID: 25960928 PMCID: PMC4423420 DOI: 10.4236/jct.2014.514131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Promoter silencing by ectopic de novo methylation of tumor suppressor genes has been proposed as comparable or equivalent to inactivating mutations as a factor in carcinogenesis. However, this hypotheses had not previously been tested by high resolution, high-coverage whole-genome methylation profiling in primary carcinomas. We have determined the genomic methylation status of a series of primary mammary carcinomas and matched control tissues by examination of more than 2.7 billion CpG dinucleotides. Most of the tumors showed variable losses of DNA methylation from all sequence compartments, but increases in promoter methylation were infrequent, very small in extent, and were observed largely at CpG-poor promoters. De novo methylation at the promoters of proto-oncogenes and tumor suppressor genes occurred at approximately the same frequency. The findings indicate that tumor suppressor silencing by de novo methylation is much less common than currently believed. We put forward a hypothesis under which the demethylation commonly observed in carcinomas is a manifestation of a defensive system that kills incipient cancer cells.
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Affiliation(s)
- Anne H O'Donnell
- Department of Genetics and Development, College of Physicians and Surgeons of Columbia University, New York, NY, USA ; Division of Genetics, Boston Children's Hospital, Boston, MA, USA
| | - John R Edwards
- Center for Pharmacogenomics, Washington University School of Medicine, St. Louis, MO, USA
| | - Robert A Rollins
- Department of Genetics and Development, College of Physicians and Surgeons of Columbia University, New York, NY, USA ; Pfizer BioTherapeutics Research and Development, Center for Integrative Biology and Biotherapeutics, Pearl River, NY, USA
| | - Nathan D Vander Kraats
- Center for Pharmacogenomics, Washington University School of Medicine, St. Louis, MO, USA
| | - Tao Su
- Department of Pathology, College of Physicians and Surgeons of Columbia University, New York, NY, USA
| | - Hanina H Hibshoosh
- Department of Pathology, College of Physicians and Surgeons of Columbia University, New York, NY, USA
| | - Timothy H Bestor
- Department of Genetics and Development, College of Physicians and Surgeons of Columbia University, New York, NY, USA
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333
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Marzese DM, Scolyer RA, Huynh JL, Huang SK, Hirose H, Chong KK, Kiyohara E, Wang J, Kawas NP, Donovan NC, Hata K, Wilmott JS, Murali R, Buckland ME, Shivalingam B, Thompson JF, Morton DL, Kelly DF, Hoon DS. Epigenome-wide DNA methylation landscape of melanoma progression to brain metastasis reveals aberrations on homeobox D cluster associated with prognosis. Hum Mol Genet 2014; 23:226-38. [PMID: 24014427 PMCID: PMC3857956 DOI: 10.1093/hmg/ddt420] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 07/29/2013] [Accepted: 08/26/2013] [Indexed: 12/19/2022] Open
Abstract
Melanoma brain metastasis (MBM) represents a frequent complication of cutaneous melanoma. Despite aggressive multi-modality therapy, patients with MBM often have a survival rate of <1 year. Alteration in DNA methylation is a major hallmark of tumor progression and metastasis; however, it remains largely unexplored in MBM. In this study, we generated a comprehensive DNA methylation landscape through the use of genome-wide copy number, DNA methylation and gene expression data integrative analysis of melanoma progression to MBM. A progressive genome-wide demethylation in low CpG density and an increase in methylation level of CpG islands according to melanoma progression were observed. MBM-specific partially methylated domains (PMDs) affecting key brain developmental processes were identified. Differentially methylated CpG sites between MBM and lymph node metastasis (LNM) from patients with good prognosis were identified. Among the most significantly affected genes were the HOX family members. DNA methylation of HOXD9 gene promoter affected transcript and protein expression and was significantly higher in MBM than that in early stages. A MBM-specific PMD was identified in this region. Low methylation level of this region was associated with active HOXD9 expression, open chromatin and histone modifications associated with active transcription. Demethylating agent induced HOXD9 expression in melanoma cell lines. The clinical relevance of this finding was verified in an independent large cohort of melanomas (n = 145). Patients with HOXD9 hypermethylation in LNM had poorer disease-free and overall survival. This epigenome-wide study identified novel methylated genes with functional and clinical implications for MBM patients.
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Affiliation(s)
| | - Richard A. Scolyer
- Departments of Tissue Oncology and Diagnostic Pathology and Melanoma and Surgical Oncology, Royal Prince Alfred Hospital, Sydney, NSW, Australia
- Sydney Medical School, The University of Sydney, Sydney, NSW, Australia
- Melanoma Institute Australia, Sydney, NSW 2006, Australia
| | | | | | | | | | | | | | | | | | | | | | - Rajmohan Murali
- Department of Pathology
- Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065USA
| | | | | | - John F. Thompson
- Sydney Medical School, The University of Sydney, Sydney, NSW, Australia
- Melanoma Institute Australia, Sydney, NSW 2006, Australia
| | - Donald L. Morton
- Division of Surgical Oncology, John Wayne Cancer Institute (JWCI), 2200 Santa Monica Blvd, Santa Monica, CA 90404, USA
| | - Daniel F. Kelly
- Division of Surgical Oncology, John Wayne Cancer Institute (JWCI), 2200 Santa Monica Blvd, Santa Monica, CA 90404, USA
- Brain Tumor Center, Saint John's Health Center, Santa Monica, CA 90404, USA
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334
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Nag A, Savova V, Fung HL, Miron A, Yuan GC, Zhang K, Gimelbrant AA. Chromatin signature of widespread monoallelic expression. eLife 2013; 2:e01256. [PMID: 24381246 PMCID: PMC3873816 DOI: 10.7554/elife.01256] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In mammals, numerous autosomal genes are subject to mitotically stable monoallelic expression (MAE), including genes that play critical roles in a variety of human diseases. Due to challenges posed by the clonal nature of MAE, very little is known about its regulation; in particular, no molecular features have been specifically linked to MAE. In this study, we report an approach that distinguishes MAE genes in human cells with great accuracy: a chromatin signature consisting of chromatin marks associated with active transcription (H3K36me3) and silencing (H3K27me3) simultaneously occurring in the gene body. The MAE signature is present in ∼20% of ubiquitously expressed genes and over 30% of tissue-specific genes across cell types. Notably, it is enriched among key developmental genes that have bivalent chromatin structure in pluripotent cells. Our results open a new approach to the study of MAE that is independent of polymorphisms, and suggest that MAE is linked to cell differentiation. DOI:http://dx.doi.org/10.7554/eLife.01256.001 Understanding how genes are activated and silenced is one of the central challenges in modern biology. These processes underpin the development of a fertilized egg into a complex organism, and they can also lead to life-threatening diseases when they go wrong. There are two copies of each gene in a human cell, a maternal copy and a paternal copy, and it is thought that both copies are usually regulated together. However, there are exceptions to this rule: for certain genes only the maternal copy is expressed as a protein in some cells, whereas the paternal copy is expressed in other cells. This form of gene regulation, which is called monoallelic expression, can result in neighboring cells heading down very different paths. In extreme cases, depending on the differences between the two copies of the gene, cells that express one copy may function normally, while cells where the other copy is activated will start forming tumors. However, despite these potentially grave consequences, and early results which suggested that monoallelic expression affected a large number of human and mouse genes, it has proved to be a major technical challenge to identify these genes in most cell types. Now, Nag, Savova et al. have discovered a molecular signature that can be used to detect monoallelic expression. The signature was found in chromatin, the densely packed structure formed by DNA and proteins inside the cell nucleus. Nag, Savova et al. discovered that the genes that are subject to monoallelic expression are bound with proteins that are modified in two contrasting ways. One modification, which is usually a sign of gene silencing, is prevalent on the inactive copy of the gene, and the other, which often marks active genes, is chiefly present on the active copy. Nag, Savova et al. report that these modifications are found in different sets of genes in different cell types, indicating distinct genome-wide patterns of monoallelic expression. The chromatin signature approach lets them estimate the fraction of human genes that are subject to monoallelic expression. This number is surprisingly high: about 20% of commonly expressed genes and more than one-third of tissue-specific genes. In a particularly intriguing finding, almost all bivalent genes—a subset of genes that are involved in determining the fate of cell during development—are estimated to become monoallelic when they are activated. In addition to these unexpected findings, the chromatin signature approach opens the door to exploring monoallelic expression as a form of gene regulation in all types of cells and, ultimately, to understanding how it is involved in both normal development and in disease. DOI:http://dx.doi.org/10.7554/eLife.01256.002
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Affiliation(s)
- Anwesha Nag
- Department of Cancer Biology and Center for Cancer Systems Biology, Dana-Farber Cancer Institute, Boston, United States
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335
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Abstract
Our advances in technology allow us to sequence DNA to uncover genetic differences not only between individuals, but also between normal and diseased cells within an individual. However, there is still a lot we have yet to understand regarding the epigenetic mechanisms that also contribute to our individuality and to disease. The 80th Biochemical Society Annual Symposium entitled Epigenetic Mechanisms in Development and Disease brought together some leading researchers in the field who discussed their latest insights into epigenetic mechanisms. Methylation of DNA has been the focus of much study from both a developmental perspective and imprinting of genes to its contribution to diseases such as cancer. Recently, the modification of methylcytosine to hydoxymethylcytosine within cells was uncovered, which opened a host of potential new mechanisms, and a flurry of new studies are underway to uncover its significance. Epigenetics is not confined to a study of DNA, and the post-translational modifications on the histone proteins have a significant role to play in regulating gene expression. There are many different modifications and, as shown at the Symposium, new variations used by cells are still being uncovered. We are some way to identifying how these modifications are added and removed and the protein complexes responsible for these changes. A focus on the function of the complexes and the interactions between individual modifications to regulate gene expression is advancing our knowledge, as discussed in the accompanying papers, although there are clearly plenty of opportunities for new breakthroughs to be made.
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336
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Gordon K, Clouaire T, Bao XX, Kemp SE, Xenophontos M, de Las Heras JI, Stancheva I. Immortality, but not oncogenic transformation, of primary human cells leads to epigenetic reprogramming of DNA methylation and gene expression. Nucleic Acids Res 2013; 42:3529-41. [PMID: 24371281 PMCID: PMC3973294 DOI: 10.1093/nar/gkt1351] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Tumourigenic transformation of normal cells into cancer typically involves several steps resulting in acquisition of unlimited growth potential, evasion of apoptosis and non-responsiveness to growth inhibitory signals. Both genetic and epigenetic changes can contribute to cancer development and progression. Given the vast genetic heterogeneity of human cancers and difficulty to monitor cancer-initiating events in vivo, the precise relationship between acquisition of genetic mutations and the temporal progression of epigenetic alterations in transformed cells is largely unclear. Here, we use an in vitro model system to investigate the contribution of cellular immortality and oncogenic transformation of primary human cells to epigenetic reprogramming of DNA methylation and gene expression. Our data demonstrate that extension of replicative life span of the cells is sufficient to induce accumulation of DNA methylation at gene promoters and large-scale changes in gene expression in a time-dependent manner. In contrast, continuous expression of cooperating oncogenes in immortalized cells, although essential for anchorage-independent growth and evasion of apoptosis, does not affect de novo DNA methylation at promoters and induces subtle expression changes. Taken together, these observations imply that cellular immortality promotes epigenetic adaptation to highly proliferative state, whereas transforming oncogenes confer additional properties to transformed human cells.
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Affiliation(s)
- Katrina Gordon
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, Mayfield Road, Edinburgh EH9 3JR, UK
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337
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Malouf GG, Taube JH, Lu Y, Roysarkar T, Panjarian S, Estecio MR, Jelinek J, Yamazaki J, Raynal NJM, Long H, Tahara T, Tinnirello A, Ramachandran P, Zhang XY, Liang S, Mani SA, Issa JPJ. Architecture of epigenetic reprogramming following Twist1-mediated epithelial-mesenchymal transition. Genome Biol 2013; 14:R144. [PMID: 24367927 PMCID: PMC4053791 DOI: 10.1186/gb-2013-14-12-r144] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 12/24/2013] [Indexed: 12/21/2022] Open
Abstract
Background Epithelial-mesenchymal transition (EMT) is known to impart metastasis and stemness characteristics in breast cancer. To characterize the epigenetic reprogramming following Twist1-induced EMT, we characterized the epigenetic and transcriptome landscapes using whole-genome transcriptome analysis by RNA-seq, DNA methylation by digital restriction enzyme analysis of methylation (DREAM) and histone modifications by CHIP-seq of H3K4me3 and H3K27me3 in immortalized human mammary epithelial cells relative to cells induced to undergo EMT by Twist1. Results EMT is accompanied by focal hypermethylation and widespread global DNA hypomethylation, predominantly within transcriptionally repressed gene bodies. At the chromatin level, the number of gene promoters marked by H3K4me3 increases by more than one fifth; H3K27me3 undergoes dynamic genomic redistribution characterized by loss at half of gene promoters and overall reduction of peak size by almost half. This is paralleled by increased phosphorylation of EZH2 at serine 21. Among genes with highly altered mRNA expression, 23.1% switch between H3K4me3 and H3K27me3 marks, and those point to the master EMT targets and regulators CDH1, PDGFRα and ESRP1. Strikingly, Twist1 increases the number of bivalent genes by more than two fold. Inhibition of the H3K27 methyltransferases EZH2 and EZH1, which form part of the Polycomb repressive complex 2 (PRC2), blocks EMT and stemness properties. Conclusions Our findings demonstrate that the EMT program requires epigenetic remodeling by the Polycomb and Trithorax complexes leading to increased cellular plasticity. This suggests that inhibiting epigenetic remodeling and thus decrease plasticity will prevent EMT, and the associated breast cancer metastasis.
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338
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Stirzaker C, Taberlay PC, Statham AL, Clark SJ. Mining cancer methylomes: prospects and challenges. Trends Genet 2013; 30:75-84. [PMID: 24368016 DOI: 10.1016/j.tig.2013.11.004] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 11/22/2013] [Accepted: 11/26/2013] [Indexed: 12/31/2022]
Abstract
There are over 28 million CpG sites in the human genome. Assessing the methylation status of each of these sites will be required to understand fully the role of DNA methylation in health and disease. Genome-wide analysis, using arrays and high-throughput sequencing, has enabled assessment of large fractions of the methylome, but each protocol comes with unique advantages and disadvantages. Notably, except for whole-genome bisulfite sequencing, most commonly used genome-wide methods detect <5% of all CpG sites. Here, we discuss approaches for methylome studies and compare genome coverage of promoters, genes, and intergenic regions, and capacity to quantitate individual CpG methylation states. Finally, we examine the extent of published cancer methylomes that have been generated using genome-wide approaches.
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Affiliation(s)
- Clare Stirzaker
- Epigenetics Program, Garvan Institute of Medical Research, The Kinghorn Cancer Centre, Sydney 2010, NSW, Australia; St Vincent's Clinical School, University of NSW, Sydney 2010, NSW, Australia
| | - Phillippa C Taberlay
- Epigenetics Program, Garvan Institute of Medical Research, The Kinghorn Cancer Centre, Sydney 2010, NSW, Australia; St Vincent's Clinical School, University of NSW, Sydney 2010, NSW, Australia
| | - Aaron L Statham
- Epigenetics Program, Garvan Institute of Medical Research, The Kinghorn Cancer Centre, Sydney 2010, NSW, Australia
| | - Susan J Clark
- Epigenetics Program, Garvan Institute of Medical Research, The Kinghorn Cancer Centre, Sydney 2010, NSW, Australia; St Vincent's Clinical School, University of NSW, Sydney 2010, NSW, Australia.
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339
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Faraji F, Hu Y, Wu G, Goldberger NE, Walker RC, Zhang J, Hunter KW. An integrated systems genetics screen reveals the transcriptional structure of inherited predisposition to metastatic disease. Genome Res 2013; 24:227-40. [PMID: 24322557 PMCID: PMC3912413 DOI: 10.1101/gr.166223.113] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Metastasis is the result of stochastic genomic and epigenetic events leading to gene expression profiles that drive tumor dissemination. Here we exploit the principle that metastatic propensity is modified by the genetic background to generate prognostic gene expression signatures that illuminate regulators of metastasis. We also identify multiple microRNAs whose germline variation is causally linked to tumor progression and metastasis. We employ network analysis of global gene expression profiles in tumors derived from a panel of recombinant inbred mice to identify a network of co-expressed genes centered on Cnot2 that predicts metastasis-free survival. Modulating Cnot2 expression changes tumor cell metastatic potential in vivo, supporting a functional role for Cnot2 in metastasis. Small RNA sequencing of the same tumor set revealed a negative correlation between expression of the Mir216/217 cluster and tumor progression. Expression quantitative trait locus analysis (eQTL) identified cis-eQTLs at the Mir216/217 locus, indicating that differences in expression may be inherited. Ectopic expression of Mir216/217 in tumor cells suppressed metastasis in vivo. Finally, small RNA sequencing and mRNA expression profiling data were integrated to reveal that miR-3470a/b target a high proportion of network transcripts. In vivo analysis of Mir3470a/b demonstrated that both promote metastasis. Moreover, Mir3470b is a likely regulator of the Cnot2 network as its overexpression down-regulated expression of network hub genes and enhanced metastasis in vivo, phenocopying Cnot2 knockdown. The resulting data from this strategy identify Cnot2 as a novel regulator of metastasis and demonstrate the power of our systems-level approach in identifying modifiers of metastasis.
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Affiliation(s)
- Farhoud Faraji
- Metastasis Susceptibility Section, Laboratory of Cancer Biology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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340
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Saratsis AM, Kambhampati M, Snyder K, Yadavilli S, Devaney J, Harmon B, Hall J, Raabe EH, An P, Weingart M, Rood BR, Magge S, MacDonald TJ, Packer RJ, Nazarian J. Comparative multidimensional molecular analyses of pediatric diffuse intrinsic pontine glioma reveals distinct molecular subtypes. Acta Neuropathol 2013; 127:881-95. [PMID: 24297113 PMCID: PMC4028366 DOI: 10.1007/s00401-013-1218-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 11/01/2013] [Accepted: 11/15/2013] [Indexed: 02/02/2023]
Abstract
Diffuse intrinsic pontine glioma (DIPG) is a highly morbid form of pediatric brainstem glioma. Here, we present the first comprehensive protein, mRNA, and methylation profiles of fresh-frozen DIPG specimens (n = 14), normal brain tissue (n = 10), and other pediatric brain tumors (n = 17). Protein profiling identified 2,305 unique proteins indicating distinct DIPG protein expression patterns compared to other pediatric brain tumors. Western blot and immunohistochemistry validated upregulation of Clusterin (CLU), Elongation Factor 2 (EF2), and Talin-1 (TLN1) in DIPGs studied. Comparisons to mRNA expression profiles generated from tumor and adjacent normal brain tissue indicated two DIPG subgroups, characterized by upregulation of Myc (N-Myc) or Hedgehog (Hh) signaling. We validated upregulation of PTCH, a membrane receptor in the Hh signaling pathway, in a subgroup of DIPG specimens. DNA methylation analysis indicated global hypomethylation of DIPG compared to adjacent normal tissue specimens, with differential methylation of 24 genes involved in Hh and Myc pathways, correlating with protein and mRNA expression patterns. Sequencing analysis showed c.83A>T mutations in the H3F3A or HIST1H3B gene in 77 % of our DIPG cohort. Supervised analysis revealed a unique methylation pattern in mutated specimens compared to the wild-type DIPG samples. This study presents the first comprehensive multidimensional protein, mRNA, and methylation profiling of pediatric brain tumor specimens, detecting the presence of two subgroups within our DIPG cohort. This multidimensional analysis of DIPG provides increased analytical power to more fully explore molecular signatures of DIPGs, with implications for evaluating potential molecular subtypes and biomarker discovery for assessing response to therapy.
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Affiliation(s)
- Amanda M. Saratsis
- Department of Neurosurgery, Georgetown University Hospital, Washington DC, 20007, USA
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
| | - Madhuri Kambhampati
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
| | - Kendall Snyder
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
| | - Sridevi Yadavilli
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
| | - Joe Devaney
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
| | - Brennan Harmon
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
| | - Jordan Hall
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
| | - Eric H. Raabe
- Division of Neuro-Pathology, Johns Hopkins University School of Medicine, Baltimore MD 21287, USA
- Division of Pediatric Oncology, Johns Hopkins University School of Medicine, Baltimore MD 21287, USA
| | - Ping An
- Division of Neuro-Pathology, Johns Hopkins University School of Medicine, Baltimore MD 21287, USA
- Neurobiology Department, College of Basic Medical Sciences, China Medical University, 110001, China
| | - Melanie Weingart
- Division of Neuro-Pathology, Johns Hopkins University School of Medicine, Baltimore MD 21287, USA
| | - Brian R. Rood
- Division of Oncology, Center for Cancer and Immunology Research, Children’s National Medical Center, Washington DC, 20010, USA
| | - Suresh Magge
- Division of Neurosurgery, Children’s National Medical Center, Washington DC, 20010, USA
| | - Tobey J. MacDonald
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Roger J. Packer
- Division of Neurology, Center for Neuroscience Research, Children’s National Medical Center, Washington DC, 20010, USA
- Brain Tumor Institute, Center for Neuroscience and Behavioral Medicine, Children’s National Medical Center, Washington DC, USA
| | - Javad Nazarian
- Center for Genetic Medicine, Children's National Medical Center, Washington DC, 20010, USA
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
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341
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Buchi F, Masala E, Rossi A, Valencia A, Spinelli E, Sanna A, Gozzini A, Santini V. Redistribution of H3K27me3 and acetylated histone H4 upon exposure to azacitidine and decitabine results in de-repression of the AML1/ETO target gene IL3. Epigenetics 2013; 9:387-95. [PMID: 24300456 PMCID: PMC4053457 DOI: 10.4161/epi.27322] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Human acute myeloid leukemia is characterized by a block in maturation caused by genetic and epigenetic alterations. We studied the effects of low concentrations of the DNA methyltransferase (DNMT) inhibitors 5-azacitidine and decitabine on apoptosis and on chromatin remodeling in an AML1/ETO inducible model of human AML. While both DNMT inhibitors induced apoptosis, only azacitidine did so via caspase activation, possibly through its exclusive non-DNA depending effects. We evaluated histone marks for permissive chromatin, H3K4me3, and acetylated histone H4, and for non-permissive chromatin, H3K9me2, and H3K27me3, at the promoter of the IL3 gene, which is under the direct control of AML1/ETO and is critical for myeloid maturation. We observed that low concentrations of DNMT inhibitors induced a loss of H3K27me3 and gain of acetylated histone H4 at the IL3 promoter exclusively in AML1/ETO-positive cells, which was associated with transcriptional reactivation of the IL3 gene.
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Affiliation(s)
- Francesca Buchi
- Hematology; University of Florence; AOU Careggi; Florence, Italy
| | - Erico Masala
- Hematology; University of Florence; AOU Careggi; Florence, Italy
| | - Alessia Rossi
- Hematology; University of Florence; AOU Careggi; Florence, Italy
| | - Ana Valencia
- Hematology; University of Florence; AOU Careggi; Florence, Italy
| | - Elena Spinelli
- Hematology; University of Florence; AOU Careggi; Florence, Italy
| | - Alessandro Sanna
- Hematology; University of Florence; AOU Careggi; Florence, Italy
| | | | - Valeria Santini
- Hematology; University of Florence; AOU Careggi; Florence, Italy
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342
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Zhu H, Wu K, Yan W, Hu L, Yuan J, Dong Y, Li Y, Jing K, Yang Y, Guo M. Epigenetic silencing of DACH1 induces loss of transforming growth factor-β1 antiproliferative response in human hepatocellular carcinoma. Hepatology 2013; 58:2012-22. [PMID: 23787902 DOI: 10.1002/hep.26587] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 06/09/2013] [Indexed: 12/12/2022]
Abstract
UNLABELLED Human dachshund homolog 1 (DACH1) is a major component of the Retinal Determination Gene Network (RDGN) and functions as a tumor suppressor. However, the regulation of DACH1 expression and its function in hepatocellular carcinoma (HCC) remain unclear. In this study, epigenetic changes of DACH1 were analyzed in HCC cell lines and primary cancers. We found that promoter region hypermethylation was correlated with loss or reduction of DACH1 expression, and restoration of DACH1 expression was induced by 5-aza-2'-deoxycytidine (5-AZA) in HCC cell lines. Promoter region methylation was found in 42% of primary HCC. Reduced expression of DACH1 was associated with poor differentiation of HCC nodules and higher serum aspartate aminotransferase/alanine aminotransferase ratio. DACH1 suppressed cellular growth by reactivating transforming growth factor beta (TGF-β) signaling. Ectopic expression of DACH1 enhanced chemosensitivity to 5-fluorouracil (5-FU) by inducing p21 expression in HCC cells. CONCLUSION DACH1 is frequently methylated in HCC and DACH1 expression is regulated by promoter hypermethylation. Down-regulation of DACH1 is a novel mechanism for gaining resistance to the antiproliferative signaling of TGF-β1 and 5-FU resistance.
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Affiliation(s)
- Hongbin Zhu
- Department of Gastroenterology and Hepatology, Chinese PLA General Hospital, Beijing, P.R. China
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343
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Reddington JP, Sproul D, Meehan RR. DNA methylation reprogramming in cancer: does it act by re-configuring the binding landscape of Polycomb repressive complexes? Bioessays 2013; 36:134-40. [PMID: 24277643 PMCID: PMC4225474 DOI: 10.1002/bies.201300130] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
DNA methylation is a repressive epigenetic mark vital for normal development. Recent studies have uncovered an unexpected role for the DNA methylome in ensuring the correct targeting of the Polycomb repressive complexes throughout the genome. Here, we discuss the implications of these findings for cancer, where DNA methylation patterns are widely reprogrammed. We speculate that cancer-associated reprogramming of the DNA methylome leads to an altered Polycomb binding landscape, influencing gene expression by multiple modes. As the Polycomb system is responsible for the regulation of genes with key roles in cell fate decisions and cell cycle regulation, DNA methylation induced Polycomb mis-targeting could directly drive carcinogenesis and disease progression.
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Affiliation(s)
- James P Reddington
- MRC Human Genetics Unit, MRC IGMM, University of Edinburgh, Edinburgh, United Kingdom
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344
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Cruickshanks HA, McBryan T, Nelson DM, Vanderkraats ND, Shah PP, van Tuyn J, Singh Rai T, Brock C, Donahue G, Dunican DS, Drotar ME, Meehan RR, Edwards JR, Berger SL, Adams PD. Senescent cells harbour features of the cancer epigenome. Nat Cell Biol 2013; 15:1495-506. [PMID: 24270890 DOI: 10.1038/ncb2879] [Citation(s) in RCA: 245] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 10/14/2013] [Indexed: 12/13/2022]
Abstract
Altered DNA methylation and associated destabilization of genome integrity and function is a hallmark of cancer. Replicative senescence is a tumour suppressor process that imposes a limit on the proliferative potential of normal cells that all cancer cells must bypass. Here we show by whole-genome single-nucleotide bisulfite sequencing that replicative senescent human cells exhibit widespread DNA hypomethylation and focal hypermethylation. Hypomethylation occurs preferentially at gene-poor, late-replicating, lamin-associated domains and is linked to mislocalization of the maintenance DNA methyltransferase (DNMT1) in cells approaching senescence. Low-level gains of methylation are enriched in CpG islands, including at genes whose methylation and silencing is thought to promote cancer. Gains and losses of methylation in replicative senescence are thus qualitatively similar to those in cancer, and this 'reprogrammed' methylation landscape is largely retained when cells bypass senescence. Consequently, the DNA methylome of senescent cells might promote malignancy, if these cells escape the proliferative barrier.
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Affiliation(s)
- Hazel A Cruickshanks
- 1] Institute of Cancer Sciences, University of Glasgow and Beatson Institute for Cancer Research, Glasgow, G61 1BD, UK [2] [3]
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345
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Geisen S, Barturen G, Alganza ÁM, Hackenberg M, Oliver JL. NGSmethDB: an updated genome resource for high quality, single-cytosine resolution methylomes. Nucleic Acids Res 2013; 42:D53-9. [PMID: 24271385 PMCID: PMC3964946 DOI: 10.1093/nar/gkt1202] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The updated release of ‘NGSmethDB’ (http://bioinfo2.ugr.es/NGSmethDB) is a repository for single-base whole-genome methylome maps for the best-assembled eukaryotic genomes. Short-read data sets from NGS bisulfite-sequencing projects of cell lines, fresh and pathological tissues are first pre-processed and aligned to the corresponding reference genome, and then the cytosine methylation levels are profiled. One major improvement is the application of a unique bioinformatics protocol to all data sets, thereby assuring the comparability of all values with each other. We implemented stringent quality controls to minimize important error sources, such as sequencing errors, bisulfite failures, clonal reads or single nucleotide variants (SNVs). This leads to reliable and high-quality methylomes, all obtained under uniform settings. Another significant improvement is the detection in parallel of SNVs, which might be crucial for many downstream analyses (e.g. SNVs and differential-methylation relationships). A next-generation methylation browser allows fast and smooth scrolling and zooming, thus speeding data download/upload, at the same time requiring fewer server resources. Several data mining tools allow the comparison/retrieval of methylation levels in different tissues or genome regions. NGSmethDB methylomes are also available as native tracks through a UCSC hub, which allows comparison with a wide range of third-party annotations, in particular phenotype or disease annotations.
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Affiliation(s)
- Stefanie Geisen
- Facultad de Ciencias, Departmento de Genética, Universidad de Granada, 18071-Granada, Spain and Laboratorio de Bioinformática, Instituto de Biotecnología, Centro de Investigación Biomédica, 18100-Granada, Spain
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346
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Szulwach KE, Jin P. Integrating DNA methylation dynamics into a framework for understanding epigenetic codes. Bioessays 2013; 36:107-17. [PMID: 24242211 DOI: 10.1002/bies.201300090] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Genomic function is dictated by a combination of DNA sequence and the molecular mechanisms controlling access to genetic information. Access to DNA can be determined by the interpretation of covalent modifications that influence the packaging of DNA into chromatin, including DNA methylation and histone modifications. These modifications are believed to be forms of "epigenetic codes" that exist in discernable combinations that reflect cellular phenotype. Although DNA methylation is known to play important roles in gene regulation and genomic function, its contribution to the encoding of epigenetic information is just beginning to emerge. Here we discuss paradigms associated with the various components of DNA methylation/demethylation and recent advances in the understanding of its dynamic regulation in the genome, integrating these mechanisms into a framework to explain how DNA methylation could contribute to epigenetic codes.
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Affiliation(s)
- Keith E Szulwach
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
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347
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Raddatz G, Hagemann S, Aran D, Söhle J, Kulkarni PP, Kaderali L, Hellman A, Winnefeld M, Lyko F. Aging is associated with highly defined epigenetic changes in the human epidermis. Epigenetics Chromatin 2013; 6:36. [PMID: 24279375 PMCID: PMC3819645 DOI: 10.1186/1756-8935-6-36] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 10/08/2013] [Indexed: 12/22/2022] Open
Abstract
Background Altered DNA methylation patterns represent an attractive mechanism for understanding the phenotypic changes associated with human aging. Several studies have described global and complex age-related methylation changes, but their structural and functional significance has remained largely unclear. Results We have used transcriptome sequencing to characterize age-related gene expression changes in the human epidermis. The results revealed a significant set of 75 differentially expressed genes with a strong functional relationship to skin homeostasis. We then used whole-genome bisulfite sequencing to identify age-related methylation changes at single-base resolution. Data analysis revealed no global aberrations, but rather highly localized methylation changes, particularly in promoter and enhancer regions that were associated with altered transcriptional activity. Conclusions Our results suggest that the core developmental program of human skin is stably maintained through the aging process and that aging is associated with a limited destabilization of the epigenome at gene regulatory elements.
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348
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Nabilsi NH, Ryder DJ, Peraza-Penton AC, Poudyal R, Loose DS, Kladde MP. Local depletion of DNA methylation identifies a repressive p53 regulatory region in the NEK2 promoter. J Biol Chem 2013; 288:35940-51. [PMID: 24163369 DOI: 10.1074/jbc.m113.523837] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Genome-scale mapping suggests that the function of DNA methylation varies with genomic context beyond transcriptional repression. However, the use of DNA-demethylating agents (e.g. 5-aza-2'-deoxycytidine (5aza-dC)) to study epigenetic regulation often focuses on gene activation and ignores repression elicited by 5aza-dC. Here, we show that repression of NEK2, which encodes the never in mitosis A (NIMA)-related kinase, by 5aza-dC is context-specific as NEK2 transcript levels were reduced in HCT116 colon cancer cells but not in isogenic p53(-/-) cells. Bisulfite sequencing showed that DNA methylation was restricted to the distal region of the NEK2 promoter. Demethylation by 5aza-dC was associated with increased accessibility to micrococcal nuclease, i.e. nucleosome depletion. Conversely, methyltransferase accessibility protocol for individual templates (MAPit) methylation footprinting showed that nucleosome occupancy and DNA methylation at the distal promoter were significantly increased in p53(-/-) cells, suggesting dynamic regulation of chromatin structure at this region by p53 in HCT116 cells. Stabilization of endogenous p53 by doxorubicin or ectopic expression of p53, but not a p53 DNA-binding mutant, decreased NEK2 expression. Chromatin immunoprecipitation demonstrated direct and specific association of p53 with the distal NEK2 promoter, which was enhanced by doxorubicin. Luciferase reporters confirmed that this region is required for p53-mediated repression of NEK2 promoter activity. Lastly, modulation of p53 abundance altered nucleosome occupancy and DNA methylation at its binding region. These results identify NEK2 as a novel p53-repressed gene, illustrate that its repression by 5aza-dC is specific and associated with nucleosome reorganization, and provide evidence that identification of partially methylated regions can reveal novel p53 target genes.
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Affiliation(s)
- Nancy H Nabilsi
- From the Department of Biochemistry and Molecular Biology, University of Florida Health Cancer Center, University of Florida College of Medicine, Gainesville, Florida 32610
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349
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Zhang M, Xie S, Dong X, Zhao X, Zeng B, Chen J, Li H, Yang W, Zhao H, Wang G, Chen Z, Sun S, Hauck A, Jin W, Lai J. Genome-wide high resolution parental-specific DNA and histone methylation maps uncover patterns of imprinting regulation in maize. Genome Res 2013; 24:167-76. [PMID: 24131563 PMCID: PMC3875858 DOI: 10.1101/gr.155879.113] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Genetic imprinting is a specific epigenetic phenomenon in which a subset of genes is expressed depending on their parent-of-origin. Two types of chromatin modifications, DNA methylation and histone modification, are generally believed to be involved in the regulation of imprinting. However, the genome-wide correlation between allele-specific chromatin modifications and imprinted gene expression in maize remains elusive. Here we report genome-wide high resolution allele-specific maps of DNA methylation and histone H3 lysine 27 trimethylation (H3K27me3) in maize endosperm. For DNA methylation, thousands of parent-of-origin dependent differentially methylated regions (pDMRs) were identified. All pDMRs were uniformly paternally hypermethylated and maternally hypomethylated. We also identified 1131 allele-specific H3K27me3 peaks that are preferentially present in the maternal alleles. Maternally expressed imprinted genes (MEGs) and paternally expressed imprinted genes (PEGs) had different patterns of allele-specific DNA methylation and H3K27me3. Allele-specific expression of MEGs was not directly related to allele-specific H3K27me3, and only a subset of MEGs was associated with maternal-specific DNA demethylation, which was primarily located in the upstream and 5' portion of gene body regions. In contrast, allele-specific expression of a majority of PEGs was related to maternal-specific H3K27me3, with a subgroup of PEGs also associated with maternal-specific DNA demethylation. Both pDMRs and maternal H3K27me3 peaks associated with PEGs are enriched in gene body regions. Our results indicate highly complex patterns of regulation on genetic imprinting in maize endosperm.
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Affiliation(s)
- Mei Zhang
- State Key Laboratory of Agrobiotechnology and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China
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350
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Plass C, Pfister SM, Lindroth AM, Bogatyrova O, Claus R, Lichter P. Mutations in regulators of the epigenome and their connections to global chromatin patterns in cancer. Nat Rev Genet 2013; 14:765-80. [DOI: 10.1038/nrg3554] [Citation(s) in RCA: 315] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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