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Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization

Progression to malignancy requires that cells overcome senescence and switch to an immortal phenotype. Thus, exploring the genetic and epigenetic changes that occur during senescence/immortalization may help elucidate crucial events that lead to cell transformation. In the present study, we have glo...

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Autores principales: Tommasi, Stella, Zheng, Albert, Weninger, Annette, Bates, Steven E., Li, Xuejun Arthur, Wu, Xiwei, Hollstein, Monica, Besaratinia, Ahmad
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Oxford University Press 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3592471/
https://www.ncbi.nlm.nih.gov/pubmed/23143272
http://dx.doi.org/10.1093/nar/gks1051
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author Tommasi, Stella
Zheng, Albert
Weninger, Annette
Bates, Steven E.
Li, Xuejun Arthur
Wu, Xiwei
Hollstein, Monica
Besaratinia, Ahmad
author_facet Tommasi, Stella
Zheng, Albert
Weninger, Annette
Bates, Steven E.
Li, Xuejun Arthur
Wu, Xiwei
Hollstein, Monica
Besaratinia, Ahmad
author_sort Tommasi, Stella
collection PubMed
description Progression to malignancy requires that cells overcome senescence and switch to an immortal phenotype. Thus, exploring the genetic and epigenetic changes that occur during senescence/immortalization may help elucidate crucial events that lead to cell transformation. In the present study, we have globally profiled DNA methylation in relation to gene expression in primary, senescent and immortalized mouse embryonic fibroblasts. Using a high-resolution genome-wide mapping technique, followed by extensive locus-specific validation assays, we have identified 24 CpG islands that display significantly higher levels of CpG methylation in immortalized cell lines as compared to primary murine fibroblasts. Several of these hypermethylated CpG islands are associated with genes involved in the MEK–ERK pathway, one of the most frequently disrupted pathways in cancer. Approximately half of the hypermethylated targets are developmental regulators, and bind to the repressive Polycomb group (PcG) proteins, often in the context of bivalent chromatin in mouse embryonic stem cells. Because PcG-associated aberrant DNA methylation is a hallmark of several human malignancies, our methylation data suggest that epigenetic reprogramming of pluripotency genes may initiate cell immortalization. Consistent with methylome alterations, global gene expression analysis reveals that the vast majority of genes dysregulated during cell immortalization belongs to gene families that converge into the MEK–ERK pathway. Additionally, several dysregulated members of the MAP kinase network show concomitant hypermethylation of CpG islands. Unlocking alternative epigenetic routes for cell immortalization will be paramount for understanding crucial events leading to cell transformation. Unlike genetic alterations, epigenetic changes are reversible events, and as such, can be amenable to pharmacological interventions, which makes them appealing targets for cancer therapy when genetic approaches prove inadequate.
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spelling pubmed-35924712013-03-08 Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization Tommasi, Stella Zheng, Albert Weninger, Annette Bates, Steven E. Li, Xuejun Arthur Wu, Xiwei Hollstein, Monica Besaratinia, Ahmad Nucleic Acids Res Gene Regulation, Chromatin and Epigenetics Progression to malignancy requires that cells overcome senescence and switch to an immortal phenotype. Thus, exploring the genetic and epigenetic changes that occur during senescence/immortalization may help elucidate crucial events that lead to cell transformation. In the present study, we have globally profiled DNA methylation in relation to gene expression in primary, senescent and immortalized mouse embryonic fibroblasts. Using a high-resolution genome-wide mapping technique, followed by extensive locus-specific validation assays, we have identified 24 CpG islands that display significantly higher levels of CpG methylation in immortalized cell lines as compared to primary murine fibroblasts. Several of these hypermethylated CpG islands are associated with genes involved in the MEK–ERK pathway, one of the most frequently disrupted pathways in cancer. Approximately half of the hypermethylated targets are developmental regulators, and bind to the repressive Polycomb group (PcG) proteins, often in the context of bivalent chromatin in mouse embryonic stem cells. Because PcG-associated aberrant DNA methylation is a hallmark of several human malignancies, our methylation data suggest that epigenetic reprogramming of pluripotency genes may initiate cell immortalization. Consistent with methylome alterations, global gene expression analysis reveals that the vast majority of genes dysregulated during cell immortalization belongs to gene families that converge into the MEK–ERK pathway. Additionally, several dysregulated members of the MAP kinase network show concomitant hypermethylation of CpG islands. Unlocking alternative epigenetic routes for cell immortalization will be paramount for understanding crucial events leading to cell transformation. Unlike genetic alterations, epigenetic changes are reversible events, and as such, can be amenable to pharmacological interventions, which makes them appealing targets for cancer therapy when genetic approaches prove inadequate. Oxford University Press 2013-01 2012-11-10 /pmc/articles/PMC3592471/ /pubmed/23143272 http://dx.doi.org/10.1093/nar/gks1051 Text en © The Author(s) 2012. Published by Oxford University Press. http://creativecommons.org/licenses/by-nc/3.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc/3.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com.
spellingShingle Gene Regulation, Chromatin and Epigenetics
Tommasi, Stella
Zheng, Albert
Weninger, Annette
Bates, Steven E.
Li, Xuejun Arthur
Wu, Xiwei
Hollstein, Monica
Besaratinia, Ahmad
Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
title Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
title_full Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
title_fullStr Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
title_full_unstemmed Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
title_short Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
title_sort mammalian cells acquire epigenetic hallmarks of human cancer during immortalization
topic Gene Regulation, Chromatin and Epigenetics
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3592471/
https://www.ncbi.nlm.nih.gov/pubmed/23143272
http://dx.doi.org/10.1093/nar/gks1051
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