Chromatin dysregulation and DNA methylation at transcription start sites associated with transcriptional repression in cancers

Nat Commun. 2019 May 16;10(1):2188. doi: 10.1038/s41467-019-09937-w.

Abstract

Although promoter-associated CpG islands have been established as targets of DNA methylation changes in cancer, previous studies suggest that epigenetic dysregulation outside the promoter region may be more closely associated with transcriptional changes. Here we examine DNA methylation, chromatin marks, and transcriptional alterations to define the relationship between transcriptional modulation and spatial changes in chromatin structure. Using human papillomavirus-related oropharyngeal carcinoma as a model, we show aberrant enrichment of repressive H3K9me3 at the transcriptional start site (TSS) with methylation-associated, tumor-specific gene silencing. Further analysis identifies a hypermethylated subtype which shows a functional convergence on MYC targets and association with CREBBP/EP300 mutation. The tumor-specific shift to transcriptional repression associated with DNA methylation at TSSs was confirmed in multiple tumor types. Our data may show a common underlying epigenetic dysregulation in cancer associated with broad enrichment of repressive chromatin marks and aberrant DNA hypermethylation at TSSs in combination with MYC network activation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • CREB-Binding Protein / genetics
  • Cell Line, Tumor
  • Chromatin / metabolism*
  • DNA Methylation / genetics*
  • Datasets as Topic
  • E1A-Associated p300 Protein / genetics
  • Gene Expression Regulation, Neoplastic*
  • Gene Silencing
  • Histones / genetics
  • Histones / metabolism
  • Humans
  • Mutation
  • Neoplasms / genetics*
  • Neoplasms / pathology
  • Proto-Oncogene Proteins c-myc / metabolism
  • Signal Transduction / genetics
  • Transcription Initiation Site*

Substances

  • Chromatin
  • Histones
  • MYC protein, human
  • Proto-Oncogene Proteins c-myc
  • CREB-Binding Protein
  • CREBBP protein, human
  • E1A-Associated p300 Protein
  • EP300 protein, human