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Varmuza S, Miri K. What does genetics tell us about imprinting and the placenta connection? Cell Mol Life Sci 2015; 72:51-72. [PMID: 25194419 PMCID: PMC11114082 DOI: 10.1007/s00018-014-1714-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Revised: 08/25/2014] [Accepted: 08/27/2014] [Indexed: 01/07/2023]
Abstract
Genomic imprinting is an epigenetic gene silencing phenomenon that is specific to eutherians in the vertebrate lineage. The acquisition of both placentation and genomic imprinting has spurred interest in the possible evolutionary link for many years. In this review we examine the genetic evidence and find that while many imprinted domains are anchored by genes required for proper placenta development in a parent of origin fashion, an equal number of imprinted genes have no apparent function that depends on imprinting. Examination of recent data from studies of molecular and genetic mechanisms points to a maternal control of the selection and maintenance of imprint marks, reinforcing the importance of the oocyte in the healthy development of the placenta and fetus.
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Affiliation(s)
- Susannah Varmuza
- Department of Cell and Systems Biology, University of Toronto, 611-25 Harbord Street, Toronto, M5S 3G5, Canada,
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252
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Okae H, Chiba H, Hiura H, Hamada H, Sato A, Utsunomiya T, Kikuchi H, Yoshida H, Tanaka A, Suyama M, Arima T. Genome-wide analysis of DNA methylation dynamics during early human development. PLoS Genet 2014; 10:e1004868. [PMID: 25501653 PMCID: PMC4263407 DOI: 10.1371/journal.pgen.1004868] [Citation(s) in RCA: 178] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 11/02/2014] [Indexed: 12/28/2022] Open
Abstract
DNA methylation is globally reprogrammed during mammalian preimplantation development, which is critical for normal development. Recent reduced representation bisulfite sequencing (RRBS) studies suggest that the methylome dynamics are essentially conserved between human and mouse early embryos. RRBS is known to cover 5–10% of all genomic CpGs, favoring those contained within CpG-rich regions. To obtain an unbiased and more complete representation of the methylome during early human development, we performed whole genome bisulfite sequencing of human gametes and blastocysts that covered>70% of all genomic CpGs. We found that the maternal genome was demethylated to a much lesser extent in human blastocysts than in mouse blastocysts, which could contribute to an increased number of imprinted differentially methylated regions in the human genome. Global demethylation of the paternal genome was confirmed, but SINE-VNTR-Alu elements and some other tandem repeat-containing regions were found to be specifically protected from this global demethylation. Furthermore, centromeric satellite repeats were hypermethylated in human oocytes but not in mouse oocytes, which might be explained by differential expression of de novo DNA methyltransferases. These data highlight both conserved and species-specific regulation of DNA methylation during early mammalian development. Our work provides further information critical for understanding the epigenetic processes underlying differentiation and pluripotency during early human development. DNA methylation reprogramming after fertilization is critical for normal mammalian development. Early embryos are sensitive to environmental stresses and a number of reports have pointed out the increased risk of DNA methylation errors associated with assisted reproduction technologies. Therefore, it is very important to understand normal DNA methylation patterns during early human development. Recent reduced representation bisulfite sequencing studies reported partial methylomes of human gametes and early embryos. To provide a more comprehensive view of DNA methylation dynamics during early human development, we report on whole genome bisulfite sequencing of human gametes and blastocysts. We show that the paternal genome is globally demethylated in blastocysts whereas the maternal genome is demethylated to a much lesser extent. We also reveal unique regulation of imprinted differentially methylated regions, gene bodies and repeat sequences during early human development. Our high-resolution methylome maps are essential to understand epigenetic reprogramming by human oocytes and will aid in the preimplantation epigenetic diagnosis of human embryos.
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Affiliation(s)
- Hiroaki Okae
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- JST, CREST, Saitama, Japan
| | - Hatsune Chiba
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- JST, CREST, Saitama, Japan
| | - Hitoshi Hiura
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- JST, CREST, Saitama, Japan
| | - Hirotaka Hamada
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- JST, CREST, Saitama, Japan
| | - Akiko Sato
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- St. Luke Clinic Laboratory, Oita, Japan
| | | | - Hiroyuki Kikuchi
- Yoshida Ladies Clinic Center for Reproductive Medicine, Sendai, Japan
| | - Hiroaki Yoshida
- Yoshida Ladies Clinic Center for Reproductive Medicine, Sendai, Japan
| | - Atsushi Tanaka
- St. Mother Clinic Laboratory, Kitakyushu, Fukuoka, Japan
| | - Mikita Suyama
- JST, CREST, Saitama, Japan
- Division of Bioinformatics, Medical Institute of Bioregulation, Kyushu University, Maidashi 3-1-1, Fukuoka, Japan
| | - Takahiro Arima
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Sendai, Japan
- JST, CREST, Saitama, Japan
- * E-mail:
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253
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Johannesson B, Sagi I, Gore A, Paull D, Yamada M, Golan-Lev T, Li Z, LeDuc C, Shen Y, Stern S, Xu N, Ma H, Kang E, Mitalipov S, Sauer MV, Zhang K, Benvenisty N, Egli D. Comparable frequencies of coding mutations and loss of imprinting in human pluripotent cells derived by nuclear transfer and defined factors. Cell Stem Cell 2014; 15:634-42. [PMID: 25517467 DOI: 10.1016/j.stem.2014.10.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 08/19/2014] [Accepted: 10/06/2014] [Indexed: 12/26/2022]
Abstract
The recent finding that reprogrammed human pluripotent stem cells can be derived by nuclear transfer into human oocytes as well as by induced expression of defined factors has revitalized the debate on whether one approach might be advantageous over the other. Here we compare the genetic and epigenetic integrity of human nuclear-transfer embryonic stem cell (NT-ESC) lines and isogenic induced pluripotent stem cell (iPSC) lines, derived from the same somatic cell cultures of fetal, neonatal, and adult origin. The two cell types showed similar genome-wide gene expression and DNA methylation profiles. Importantly, NT-ESCs and iPSCs had comparable numbers of de novo coding mutations, but significantly more than parthenogenetic ESCs. As iPSCs, NT-ESCs displayed clone- and gene-specific aberrations in DNA methylation and allele-specific expression of imprinted genes. The occurrence of these genetic and epigenetic defects in both NT-ESCs and iPSCs suggests that they are inherent to reprogramming, regardless of derivation approach.
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Affiliation(s)
- Bjarki Johannesson
- The New York Stem Cell Foundation Research Institute, New York, NY 10032, USA
| | - Ido Sagi
- Stem Cell Unit, Department of Genetics, Silberman Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel
| | - Athurva Gore
- Department of Bioengineering, University of California at San Diego, La Jolla, CA 92093, USA
| | - Daniel Paull
- The New York Stem Cell Foundation Research Institute, New York, NY 10032, USA
| | - Mitsutoshi Yamada
- The New York Stem Cell Foundation Research Institute, New York, NY 10032, USA
| | - Tamar Golan-Lev
- Stem Cell Unit, Department of Genetics, Silberman Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel
| | - Zhe Li
- Department of Bioengineering, University of California at San Diego, La Jolla, CA 92093, USA
| | - Charles LeDuc
- Naomi Berrie Diabetes Center & Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Yufeng Shen
- Departments of Systems Biology and Biomedical Informatics, JP Sulzberger Columbia Genome Center, Columbia University Medical Center, New York, NY 10032, USA
| | - Samantha Stern
- The New York Stem Cell Foundation Research Institute, New York, NY 10032, USA
| | - Nanfang Xu
- Department of Biomedical Informatics, Columbia University Medical Center, New York, NY 10032, USA
| | - Hong Ma
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR 97239, USA
| | - Eunju Kang
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR 97239, USA
| | - Shoukhrat Mitalipov
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mark V Sauer
- Center for Women's Reproductive Care, College of Physicians and Surgeons, Columbia University, New York, NY 10019, USA
| | - Kun Zhang
- Department of Bioengineering, University of California at San Diego, La Jolla, CA 92093, USA
| | - Nissim Benvenisty
- Stem Cell Unit, Department of Genetics, Silberman Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel.
| | - Dieter Egli
- The New York Stem Cell Foundation Research Institute, New York, NY 10032, USA; Naomi Berrie Diabetes Center & Department of Pediatrics, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
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254
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Guardiola M, Oliva I, Guillaumet A, Martín-Trujillo Á, Rosales R, Vallvé JC, Sabench F, Del Castillo D, Zaina S, Monk D, Ribalta J. Tissue-specific DNA methylation profiles regulate liver-specific expression of the APOA1/C3/A4/A5 cluster and can be manipulated with demethylating agents on intestinal cells. Atherosclerosis 2014; 237:528-35. [PMID: 25463085 DOI: 10.1016/j.atherosclerosis.2014.10.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/17/2014] [Accepted: 10/19/2014] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The tissue-specific expression profiles of genes within the APOA1/C3/A4/A5 cluster play an important role in lipid metabolism regulation. We hypothesize that the tissue-specific expression of the APOA1/C3/A4/A5 gene cluster will show an inverse pattern with DNA methylation, and that repression in non- or low-expressing tissue, such as the intestine, can be reversed using epigenetic drugs. METHODS AND RESULTS We analyzed DNA samples from different human adult tissues (liver, intestine, leukocytes, brain, kidney, pancreas, muscle and sperm) using the Infinium HumanMethyation450 BeadChip array. DNA methylation profiles in APOA1/C3/A4/A5 gene cluster were confirmed by bisulfite PCR and pyrosequencing. To determine whether the observed tissue-specific methylation was associated with the expression profile we exposed intestinal TC7/Caco-2 cells to the demethylating agent 5-Aza-2'-deoxycytidine and monitored intestinal APOA1/C3/A4/A5 transcript re-expression by RT-qPCR. The promoters of APOA1, APOC3 and APOA5 genes were less methylated in liver compared to other tissues, and APOA4 gene was highly methylated in most tissues and partially methylated in liver and intestine. In TC7/Caco-2 cells, 5-Aza-2'-deoxycytidine treatment induced a decrease between 37 and 24% in the methylation levels of APOA1/C3/A4/A5 genes and a concomitant re-expression mainly in APOA1, APOA4 and APOA5 genes ranging from 22 to 600%. CONCLUSIONS We have determined the methylation patterns of the APOA1/C3/A4/A5 cluster that may be directly involved in the transcriptional regulation of this cluster. DNA demethylation of intestinal cells increases the RNA levels especially of APOA1, APOA4 and APOA5 genes.
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Affiliation(s)
- Montse Guardiola
- Unitat de Recerca en Lípids i Arteriosclerosi, Universitat Rovira i Virgili, IISPV, CIBERDEM, Spain.
| | - Iris Oliva
- Unitat de Recerca en Lípids i Arteriosclerosi, Universitat Rovira i Virgili, IISPV, CIBERDEM, Spain.
| | - Amy Guillaumet
- Imprinting and Cancer Group, Epigenetics and Cancer Biology Program (PEBC), Bellvitge Institute for Biomedical Research (IDIBELL), Barcelona, Spain.
| | - Álex Martín-Trujillo
- Imprinting and Cancer Group, Epigenetics and Cancer Biology Program (PEBC), Bellvitge Institute for Biomedical Research (IDIBELL), Barcelona, Spain.
| | - Roser Rosales
- Unitat de Recerca en Lípids i Arteriosclerosi, Universitat Rovira i Virgili, IISPV, CIBERDEM, Spain.
| | - Joan Carles Vallvé
- Unitat de Recerca en Lípids i Arteriosclerosi, Universitat Rovira i Virgili, IISPV, CIBERDEM, Spain.
| | - Fàtima Sabench
- Unitat de Recerca en Cirurgia, Universitat Rovira i Virgili, IISPV, Spain.
| | | | - Silvio Zaina
- Cancer Epigenetics Group, Epigenetics and Cancer Biology Program (PEBC), Bellvitge Institute for Biomedical Research (IDIBELL), Barcelona, Spain; Department of Medical Sciences, Division of Health Sciences, León Campus, University of Guanajuato, Mexico.
| | - David Monk
- Imprinting and Cancer Group, Epigenetics and Cancer Biology Program (PEBC), Bellvitge Institute for Biomedical Research (IDIBELL), Barcelona, Spain.
| | - Josep Ribalta
- Unitat de Recerca en Lípids i Arteriosclerosi, Universitat Rovira i Virgili, IISPV, CIBERDEM, Spain.
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255
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Azzi S, Blaise A, Steunou V, Harbison MD, Salem J, Brioude F, Rossignol S, Habib WA, Thibaud N, Neves CD, Jule ML, Brachet C, Heinrichs C, Bouc YL, Netchine I. Complex tissue-specific epigenotypes in Russell-Silver Syndrome associated with 11p15 ICR1 hypomethylation. Hum Mutat 2014; 35:1211-20. [PMID: 25044976 DOI: 10.1002/humu.22623] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 07/02/2014] [Indexed: 01/13/2023]
Abstract
Russell-Silver Syndrome (RSS) is a prenatal and postnatal growth retardation syndrome caused mainly by 11p15 ICR1 hypomethylation. Clinical presentation is heterogeneous in RSS patients with 11p15 ICR1 hypomethylation. We previously identified a subset of RSS patients with 11p15 ICR1 and multilocus hypomethylation. Here, we examine the relationships between IGF2 expression, 11p15 ICR1 methylation, and multilocus imprinting defects in various cell types from 39 RSS patients with 11p15 ICR1 hypomethylation in leukocyte DNA. 11p15 ICR1 hypomethylation was more pronounced in leukocytes than in buccal mucosa cells. Skin fibroblast IGF2 expression was correlated with the degree of ICR1 hypomethylation. Different tissue-specific multilocus methylation defects coexisted in 38% of cases, with some loci hypomethylated and others hypermethylated within the same cell type in some cases. Our new results suggest that tissue-specific epigenotypes may lead to clinical heterogeneity in RSS.
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Affiliation(s)
- Salah Azzi
- INSERM, UMR_S 938, CDR Saint-Antoine, Paris, F-75012, France; Sorbonne Universités, UPMC Univ Paris 06, UMR_S 938, CDR Saint-Antoine, Paris, F-75012, France; APHP, Armand Trousseau Hospital, Pediatric Endocrinology, Paris, France
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256
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257
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Wei Y, Su J, Liu H, Lv J, Wang F, Yan H, Wen Y, Liu H, Wu Q, Zhang Y. MetaImprint: an information repository of mammalian imprinted genes. Development 2014; 141:2516-23. [DOI: 10.1242/dev.105320] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Genomic imprinting is a complex genetic and epigenetic phenomenon that plays important roles in mammalian development and diseases. Mammalian imprinted genes have been identified widely by experimental strategies or predicted using computational methods. Systematic information for these genes would be necessary for the identification of novel imprinted genes and the analysis of their regulatory mechanisms and functions. Here, a well-designed information repository, MetaImprint (http://bioinfo.hrbmu.edu.cn/MetaImprint), is presented, which focuses on the collection of information concerning mammalian imprinted genes. The current version of MetaImprint incorporates 539 imprinted genes, including 255 experimentally confirmed genes, and their detailed research courses from eight mammalian species. MetaImprint also hosts genome-wide genetic and epigenetic information of imprinted genes, including imprinting control regions, single nucleotide polymorphisms, non-coding RNAs, DNA methylation and histone modifications. Information related to human diseases and functional annotation was also integrated into MetaImprint. To facilitate data extraction, MetaImprint supports multiple search options, such as by gene ID and disease name. Moreover, a configurable Imprinted Gene Browser was developed to visualize the information on imprinted genes in a genomic context. In addition, an Epigenetic Changes Analysis Tool is provided for online analysis of DNA methylation and histone modification differences of imprinted genes among multiple tissues and cell types. MetaImprint provides a comprehensive information repository of imprinted genes, allowing researchers to investigate systematically the genetic and epigenetic regulatory mechanisms of imprinted genes and their functions in development and diseases.
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Affiliation(s)
- Yanjun Wei
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150081, China
| | - Jianzhong Su
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150081, China
| | - Hongbo Liu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, China
| | - Jie Lv
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, China
| | - Fang Wang
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150081, China
| | - Haidan Yan
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150081, China
| | - Yanhua Wen
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150081, China
| | - Hui Liu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, China
| | - Qiong Wu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, China
| | - Yan Zhang
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150081, China
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258
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Rademacher K, Schröder C, Kanber D, Klein-Hitpass L, Wallner S, Zeschnigk M, Horsthemke B. Evolutionary origin and methylation status of human intronic CpG islands that are not present in mouse. Genome Biol Evol 2014; 6:1579-88. [PMID: 24923327 PMCID: PMC4122923 DOI: 10.1093/gbe/evu125] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2014] [Indexed: 12/21/2022] Open
Abstract
Imprinting of the human RB1 gene is due to the presence of a differentially methylated CpG island (CGI) in intron 2, which is part of a retrocopy derived from the PPP1R26 gene on chromosome 9. The murine Rb1 gene does not have this retrocopy and is not imprinted. We have investigated whether the RB1/Rb1 locus is unique with respect to these differences. For this, we have compared the CGIs from human and mouse by in silico analyses. We have found that the human genome does not only contain more CGIs than the mouse, but the proportion of intronic CGIs is also higher (7.7% vs. 3.5%). At least 2,033 human intronic CGIs are not present in the mouse. Among these CGIs, 104 show sequence similarities elsewhere in the human genome, which suggests that they arose from retrotransposition. We could narrow down the time points when most of these CGIs appeared during evolution. Their methylation status was analyzed in two monocyte methylome data sets from whole-genome bisulfite sequencing and in 18 published methylomes. Four CGIs, which are located in the RB1, ASRGL1, PARP11, and PDXDC1 genes, occur as methylated and unmethylated copies. In contrast to imprinted methylation at the RB1 locus, differential methylation of the ASRGL1 and PDXDC1 CGIs appears to be sequence dependent. Our study supports the notion that the epigenetic fate of the retrotransposed DNA depends on its sequence and selective forces at the integration site.
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Affiliation(s)
- Katrin Rademacher
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Christopher Schröder
- Genominformatik, Institut für Humangenetik, Medizinische Fakultät, Universität Duisburg-Essen, Essen, Germany
| | - Deniz Kanber
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Ludger Klein-Hitpass
- BioChip Labor, Institut für Zellbiologie, Medizinische Fakultät, Universität Duisburg-Essen, Essen, Germany
| | - Stefan Wallner
- Institut für Klinische Chemie und Laboratoriumsmedizin, Universitätsklinikum Regensburg, Universität Regensburg, Germany
| | - Michael Zeschnigk
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Bernhard Horsthemke
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
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259
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Romanelli V, Nakabayashi K, Vizoso M, Moran S, Iglesias-Platas I, Sugahara N, Simón C, Hata K, Esteller M, Court F, Monk D. Variable maternal methylation overlapping the nc886/vtRNA2-1 locus is locked between hypermethylated repeats and is frequently altered in cancer. Epigenetics 2014; 9:783-90. [PMID: 24589629 PMCID: PMC4063837 DOI: 10.4161/epi.28323] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Cancer is as much an epigenetic disease as a genetic one; however, the interplay between these two processes is unclear. Recently, it has been shown that a large proportion of DNA methylation variability can be explained by allele-specific methylation (ASM), either at classical imprinted loci or those regulated by underlying genetic variants. During a recent screen for imprinted differentially methylated regions, we identified the genomic interval overlapping the non-coding nc886 RNA (previously known as vtRNA2-1) as an atypical ASM that shows variable levels of methylation, predominantly on the maternal allele in many tissues. Here we show that the nc886 interval is the first example of a polymorphic imprinted DMR in humans. Further analysis of the region suggests that the interval subjected to ASM is approximately 2 kb in size and somatically acquired. An in depth analysis of this region in primary cancer samples with matching normal adjacent tissue from the Cancer Genome Atlas revealed that aberrant methylation in bladder, breast, colon and lung tumors occurred in approximately 27% of cases. Hypermethylation occurred more frequently than hypomethylation. Using additional normal-tumor paired samples we show that on rare occasions the aberrant methylation profile is due to loss-of-heterozygosity. This work therefore suggests that the nc886 locus is subject to variable allelic methylation that undergoes cancer-associated epigenetic changes in solid tumors.
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Affiliation(s)
- Valeria Romanelli
- Imprinting and Cancer Group; Cancer Epigenetic and Biology Program; Institut d'Investigació Biomedica de Bellvitge; Hospital Duran i Reynals; Barcelona, Spain
| | - Kazuhiko Nakabayashi
- Department of Maternal-Fetal Biology and Department of Molecular Endocrinology; National Research Institute for Child Health and Development; Tokyo, Japan
| | - Miguel Vizoso
- Cancer Epigenetics Group; Cancer Epigenetic and Biology Program; Institut d'Investigació Biomedica de Bellvitge; Hospital Duran i Reynals; Barcelona, Spain
| | - Sebastián Moran
- Cancer Epigenetics Group; Cancer Epigenetic and Biology Program; Institut d'Investigació Biomedica de Bellvitge; Hospital Duran i Reynals; Barcelona, Spain
| | - Isabel Iglesias-Platas
- Servicio de Neonatología; Hospital Sant Joan de Déu; Fundació Sant Joan de Déu; Barcelona, Spain
| | - Naoko Sugahara
- Department of Maternal-Fetal Biology and Department of Molecular Endocrinology; National Research Institute for Child Health and Development; Tokyo, Japan
| | - Carlos Simón
- Fundación IVI; Instituto Universitario IVI; Universidad de Valencia; INCLIVA; Valencia, Spain
| | - Kenichiro Hata
- Department of Maternal-Fetal Biology and Department of Molecular Endocrinology; National Research Institute for Child Health and Development; Tokyo, Japan
| | - Manel Esteller
- Cancer Epigenetics Group; Cancer Epigenetic and Biology Program; Institut d'Investigació Biomedica de Bellvitge; Hospital Duran i Reynals; Barcelona, Spain; Department of Physiological Sciences II; School of Medicine; University of Barcelona; Barcelona, Spain; Institucio Catalana de Recerca i Estudis Avançats (ICREA); Barcelona, Spain
| | - Franck Court
- Imprinting and Cancer Group; Cancer Epigenetic and Biology Program; Institut d'Investigació Biomedica de Bellvitge; Hospital Duran i Reynals; Barcelona, Spain
| | - David Monk
- Imprinting and Cancer Group; Cancer Epigenetic and Biology Program; Institut d'Investigació Biomedica de Bellvitge; Hospital Duran i Reynals; Barcelona, Spain
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