DNMT1-mediated epigenetic silencing of TRAF6 promotes prostate cancer tumorigenesis and metastasis by enhancing EZH2 stability

Oncogene. 2022 Aug;41(33):3991-4002. doi: 10.1038/s41388-022-02404-9. Epub 2022 Jul 8.

Abstract

A plethora of studies have shown that both DNMT1 and EZH2 have great effects on the progression of a variety of cancers. However, it remains unclear whether the expression profiles of these two epigenetic enzymes are molecularly intertwined in prostate cancer (PC), especially in castration-resistant prostate cancer (CRPC). Here, we found that DNMT1 is highly expressed and facilitates PC cell proliferation and migration. Importantly, we demonstrate that the abrogation of DNMT1 expression can induce the decreased expression of EZH2, resulting in the less aggressive capacity of PC cells. Mechanistically, we discovered that DNMT1 promotes PC tumorigenesis and metastasis by inhibiting TRAF6 transcriptional expression and subsequent TRAF6-mediated EZH2 ubiquitination. Finally, we confirmed that there is a negative correlation between DNMT1 and TRAF6 expression and a positive correlation between DNMT1 and EZH2 expression in PC patients. In this study, we first disclose that there is a direct crosstalk between DNA methyltransferase DNMT1 expression and histone methyltransferase EZH2 expression in tumorigenesis and cancer metastasis in vitro and in vivo. Our results also show that targeting DNMT1 with its inhibitor decitabine (an FDA-approved drug) is an appealing treatment strategy for CRPC patients through epigenetic suppression of both DNMT1-mediated DNA methylation and EZH2-modulated histone methylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Cell Transformation, Neoplastic / genetics
  • DNA (Cytosine-5-)-Methyltransferase 1 / genetics
  • DNA (Cytosine-5-)-Methyltransferase 1 / metabolism
  • DNA Methylation / genetics
  • Enhancer of Zeste Homolog 2 Protein / genetics
  • Enhancer of Zeste Homolog 2 Protein / metabolism
  • Epigenesis, Genetic
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Male
  • Prostatic Neoplasms, Castration-Resistant* / genetics
  • TNF Receptor-Associated Factor 6* / metabolism

Substances

  • TNF Receptor-Associated Factor 6
  • DNA (Cytosine-5-)-Methyltransferase 1
  • DNMT1 protein, human
  • EZH2 protein, human
  • Enhancer of Zeste Homolog 2 Protein