EZH2 noncanonically binds cMyc and p300 through a cryptic transactivation domain to mediate gene activation and promote oncogenesis

Nat Cell Biol. 2022 Mar;24(3):384-399. doi: 10.1038/s41556-022-00850-x. Epub 2022 Feb 24.


Canonically, EZH2 serves as the catalytic subunit of PRC2, which mediates H3K27me3 deposition and transcriptional repression. Here, we report that in acute leukaemias, EZH2 has additional noncanonical functions by binding cMyc at non-PRC2 targets and uses a hidden transactivation domain (TAD) for (co)activator recruitment and gene activation. Both canonical (EZH2-PRC2) and noncanonical (EZH2-TAD-cMyc-coactivators) activities of EZH2 promote oncogenesis, which explains the slow and ineffective antitumour effect of inhibitors of the catalytic function of EZH2. To suppress the multifaceted activities of EZH2, we used proteolysis-targeting chimera (PROTAC) to develop a degrader, MS177, which achieved effective, on-target depletion of EZH2 and interacting partners (that is, both canonical EZH2-PRC2 and noncanonical EZH2-cMyc complexes). Compared with inhibitors of the enzymatic function of EZH2, MS177 is fast-acting and more potent in suppressing cancer growth. This study reveals noncanonical oncogenic roles of EZH2, reports a PROTAC for targeting the multifaceted tumorigenic functions of EZH2 and presents an attractive strategy for treating EZH2-dependent cancers.

Publication types

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

MeSH terms

  • Carcinogenesis / genetics
  • Cytoskeletal Proteins / metabolism
  • E1A-Associated p300 Protein
  • Enhancer of Zeste Homolog 2 Protein* / genetics
  • Enhancer of Zeste Homolog 2 Protein* / metabolism
  • Humans
  • Neoplasms*
  • Proteolysis
  • Transcriptional Activation


  • Cytoskeletal Proteins
  • EZH2 protein, human
  • Enhancer of Zeste Homolog 2 Protein
  • E1A-Associated p300 Protein
  • EP300 protein, human