ERG induces a mesenchymal-like state associated with chemoresistance in leukemia cells

Oncotarget. 2014 Jan 30;5(2):351-62. doi: 10.18632/oncotarget.1449.

Abstract

Overexpression of the oncogene ERG (ETS-related gene) is an adverse prognostic factor in acute myeloid and T-cell lymphoblastic leukemia (AML and T-ALL). We hypothesize that ERG overexpression is associated with primary drug resistance thereby influencing the outcome in leukemia. We previously reported a cell-line based model of ERG overexpression which induced a potentially chemo-resistant spindle shape cell type. Herein, we report a specific transcriptional gene signature for the observed spindle shaped morphology. Genes significantly over-expressed after ERG induction strongly resembled adhesive mesenchymal-like genes that included integrins (ITGA10, ITGB5, ITGB3, ITGA2B), CD44, and CD24. Interestingly, the mesenchymal-like signature was accompanied by the repression of DNA chromatin remodeling and DNA repair genes, such as CHEK1, EZH2, SUZ12, and DNMT3a. The ERG-induced mesenchymal-like signature positively correlated with TMPRSS2-ERG prostate tissues and invasive breast cancer mRNA expression datasets reflecting a general ERG-driven pattern of malignancy. Furthermore, inhibitors modulating ERG druggable pathways WNT, PKC, and AKT, and chemotherapeutic agent cytarabine revealed ERG-induced drug resistance. In particular, PKC412 treatment enhanced proliferative rates and promoted spindle shape formation in ERG-induced cells. Nilotinib and dasatinib were effective at abolishing ERG-induced cells. Moreover, ERG overexpression also led to an increase in double strand breaks. This report provides mechanistic clues into ERG-driven drug resistance in the poor prognostic group of high ERG expressers, provides insight to improved drug targeted therapies, and provides novel markers for a mesenchymal-like state in acute leukemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antimetabolites, Antineoplastic / pharmacology
  • Apoptosis / drug effects
  • Apoptosis / physiology
  • Cytarabine / pharmacology
  • DNA Repair
  • Dasatinib
  • Drug Resistance, Neoplasm
  • Gene Expression Profiling
  • Humans
  • K562 Cells
  • Mesoderm / metabolism
  • Mesoderm / pathology
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / drug therapy
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / genetics
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / metabolism*
  • Precursor T-Cell Lymphoblastic Leukemia-Lymphoma / pathology*
  • Prognosis
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Pyrimidines / pharmacology
  • Signal Transduction
  • Thiazoles / pharmacology
  • Trans-Activators / antagonists & inhibitors
  • Trans-Activators / biosynthesis*
  • Trans-Activators / genetics
  • Trans-Activators / metabolism
  • Transcriptional Regulator ERG

Substances

  • Antimetabolites, Antineoplastic
  • ERG protein, human
  • Pyrimidines
  • Thiazoles
  • Trans-Activators
  • Transcriptional Regulator ERG
  • Cytarabine
  • Protein-Tyrosine Kinases
  • nilotinib
  • Dasatinib