Epigenetic antagonism between polycomb and SWI/SNF complexes during oncogenic transformation

Cancer Cell. 2010 Oct 19;18(4):316-28. doi: 10.1016/j.ccr.2010.09.006.

Abstract

Epigenetic alterations have been increasingly implicated in oncogenesis. Analysis of Drosophila mutants suggests that Polycomb and SWI/SNF complexes can serve antagonistic developmental roles. However, the relevance of this relationship to human disease is unclear. Here, we have investigated functional relationships between these epigenetic regulators in oncogenic transformation. Mechanistically, we show that loss of the SNF5 tumor suppressor leads to elevated expression of the Polycomb gene EZH2 and that Polycomb targets are broadly H3K27-trimethylated and repressed in SNF5-deficient fibroblasts and cancers. Further, we show antagonism between SNF5 and EZH2 in the regulation of stem cell-associated programs and that Snf5 loss activates those programs. Finally, using conditional mouse models, we show that inactivation of Ezh2 blocks tumor formation driven by Snf5 loss.

Publication types

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

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Lineage
  • Cell Proliferation
  • Cell Transformation, Neoplastic / genetics*
  • Cell Transformation, Neoplastic / pathology
  • Chromosomal Proteins, Non-Histone / deficiency
  • Chromosomal Proteins, Non-Histone / genetics*
  • Chromosomal Proteins, Non-Histone / metabolism
  • Cyclin-Dependent Kinase Inhibitor p16 / metabolism
  • Embryo, Mammalian / cytology
  • Enhancer of Zeste Homolog 2 Protein
  • Epigenesis, Genetic*
  • Fibroblasts / metabolism
  • Gene Silencing
  • Histone-Lysine N-Methyltransferase / genetics*
  • Histone-Lysine N-Methyltransferase / metabolism
  • Histones / metabolism
  • Humans
  • Lysine / metabolism
  • Methylation
  • Mice
  • Models, Genetic
  • Polycomb Repressive Complex 2
  • Polycomb-Group Proteins
  • Repressor Proteins / metabolism*
  • SMARCB1 Protein
  • Stem Cells / metabolism
  • T-Lymphocytes / cytology
  • T-Lymphocytes / metabolism
  • Transcription, Genetic
  • Up-Regulation / genetics

Substances

  • Chromosomal Proteins, Non-Histone
  • Cyclin-Dependent Kinase Inhibitor p16
  • Histones
  • Polycomb-Group Proteins
  • Repressor Proteins
  • SMARCB1 Protein
  • Smarcb1 protein, mouse
  • Enhancer of Zeste Homolog 2 Protein
  • Ezh2 protein, mouse
  • Histone-Lysine N-Methyltransferase
  • Polycomb Repressive Complex 2
  • Lysine

Associated data

  • GEO/GSE23659