Altered Runx1 subnuclear targeting enhances myeloid cell proliferation and blocks differentiation by activating a miR-24/MKP-7/MAPK network

Cancer Res. 2009 Nov 1;69(21):8249-55. doi: 10.1158/0008-5472.CAN-09-1567. Epub 2009 Oct 13.

Abstract

Disruption of Runx1/AML1 subnuclear localization, either by a single amino acid substitution or by a chromosomal translocation [e.g., t(8;21)], is linked to the etiology of acute myeloid leukemia (AML). Here, we show that this defect induces a select set of micro-RNAs (miR) in myeloid progenitor cells and AML patients with t(8;21). Both Runx1 and the t(8;21)-encoded AML1-ETO occupy the miR-24-23-27 locus and reciprocally control miR-24 transcription. miR-24 directly downregulates mitogen-activated protein kinase (MAPK) phosphatase-7 and enhances phosphorylation of both c-jun-NH(2)-kinase and p38 kinases. Expression of miR-24 stimulates myeloid cell growth, renders proliferation independent of interleukin-3, and blocks granulocytic differentiation. Thus, compromised Runx1 function induces a miR-dependent mechanism that, through MAPK signaling, enhances myeloid proliferation but blocks differentiation--key steps that contribute to leukemia.

Publication types

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

MeSH terms

  • Blotting, Western
  • Cell Differentiation
  • Cell Nucleus / metabolism
  • Cell Proliferation*
  • Chromatin Immunoprecipitation
  • Chromosomes, Human, Pair 21 / genetics
  • Chromosomes, Human, Pair 8 / genetics
  • Core Binding Factor Alpha 2 Subunit / genetics*
  • Core Binding Factor Alpha 2 Subunit / metabolism
  • Dual-Specificity Phosphatases / genetics
  • Dual-Specificity Phosphatases / metabolism*
  • Granulocytes / metabolism
  • Humans
  • Immunoenzyme Techniques
  • Interleukin-3 / metabolism
  • Leukemia, Myeloid, Acute / genetics
  • Leukemia, Myeloid, Acute / metabolism
  • Leukemia, Myeloid, Acute / pathology
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Mitogen-Activated Protein Kinase Phosphatases / genetics
  • Mitogen-Activated Protein Kinase Phosphatases / metabolism*
  • Mitogen-Activated Protein Kinases / genetics
  • Mitogen-Activated Protein Kinases / metabolism*
  • Myeloid Progenitor Cells / physiology*
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RUNX1 Translocation Partner 1 Protein
  • Reverse Transcriptase Polymerase Chain Reaction
  • Translocation, Genetic

Substances

  • AML1-ETO fusion protein, human
  • Core Binding Factor Alpha 2 Subunit
  • Interleukin-3
  • MIRN24 microRNA, human
  • MicroRNAs
  • Oncogene Proteins, Fusion
  • RNA, Messenger
  • RUNX1 Translocation Partner 1 Protein
  • RUNX1 protein, human
  • Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinase Phosphatases
  • DUSP16 protein, human
  • Dual-Specificity Phosphatases