EZH2 mediates ATO-induced apoptosis in acute myeloid leukemia cell lines through the Wnt signaling pathway

Tumour Biol. 2016 May;37(5):5919-23. doi: 10.1007/s13277-015-4463-2. Epub 2015 Nov 23.

Abstract

In this study, we examined the mechanisms associated with EZH2 mediation of apoptosis and chemoresistance to arsenic trioxide (ATO) in acute myeloid leukemia (AML) cell lines through the Wnt/β-catenin signaling pathway. The induction of spontaneous apoptosis observed in multiple EZH2-silenced leukemic cell lines was assessed by flow cytometry, and levels of Wnt/β-catenin-related expression were determined by western blot analysis. In comparison with AML control cells, EZH2-knockdown cells exhibited increased apoptosis and significant downregulation of β-catenin expression, as well as decreases in GSK-3β phosphorylation and β-catenin activation (p < 0.05 for all measurements). Additionally, EZH2 knockdown sensitized AML cells to induced cell death following administration of chemotherapeutic ATO. Our results suggested that EZH2 in leukemic cell lines might inhibit ATO-induced apoptosis and that EZH2 may be a potential therapeutic target in AML patients undergoing ATO treatment. Our findings provide new insights into the role of ATO and EZH2 in regulating AML progression.

Keywords: ATO; Acute myeloid leukemia; EZH2; Wnt/β-catenin.

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects*
  • Arsenic Trioxide
  • Arsenicals / pharmacology*
  • Cell Line, Tumor
  • Drug Resistance, Neoplasm / drug effects
  • Enhancer of Zeste Homolog 2 Protein / genetics
  • Enhancer of Zeste Homolog 2 Protein / metabolism*
  • Gene Expression
  • Gene Knockdown Techniques
  • Glycogen Synthase Kinase 3 beta / metabolism
  • HL-60 Cells
  • Humans
  • Leukemia, Myeloid, Acute / genetics
  • Leukemia, Myeloid, Acute / metabolism*
  • Oxides / pharmacology*
  • Phosphorylation
  • Wnt Signaling Pathway / drug effects*

Substances

  • Antineoplastic Agents
  • Arsenicals
  • Oxides
  • Enhancer of Zeste Homolog 2 Protein
  • Glycogen Synthase Kinase 3 beta
  • Arsenic Trioxide