The protein tyrosine phosphatase, Shp2, positively contributes to FLT3-ITD-induced hematopoietic progenitor hyperproliferation and malignant disease in vivo

Leukemia. 2013 Feb;27(2):398-408. doi: 10.1038/leu.2012.308. Epub 2012 Oct 22.

Abstract

Internal tandem duplications (ITDs) in the fms-like tyrosine kinase receptor (FLT3-ITDs) confer a poor prognosis in acute myeloid leukemia (AML). We hypothesized that increased recruitment of the protein tyrosine phosphatase, Shp2, to FLT3-ITDs contributes to FLT3 ligand (FL)-independent hyperproliferation and STAT5 activation. Co-immunoprecipitation demonstrated constitutive association of Shp2 with the FLT3-ITD, N51-FLT3, as well as with STAT5. Knockdown of Shp2 in Baf3/N51-FLT3 cells significantly reduced proliferation while having little effect on WT-FLT3-expressing cells. Consistently, mutation of N51-FLT3 tyrosine 599 to phenylalanine or genetic disruption of Shp2 in N51-FLT3-expressing bone marrow low-density mononuclear cells reduced proliferation and STAT5 activation. In transplants, genetic disruption of Shp2 in vivo yielded increased latency to and reduced severity of FLT3-ITD-induced malignancy. Mechanistically, Shp2 co-localizes with nuclear phospho-STAT5, is present at functional interferon-γ activation sites (GAS) within the BCL2L1 promoter, and positively activates the human BCL2L1 promoter, suggesting that Shp2 works with STAT5 to promote pro-leukemogenic gene expression. Further, using a small molecule Shp2 inhibitor, the proliferation of N51-FLT3-expressing bone marrow progenitors and primary AML samples was reduced in a dose-dependent manner. These findings demonstrate that Shp2 positively contributes to FLT3-ITD-induced leukemia and suggest that Shp2 inhibition may provide a novel therapeutic approach to AML.

Publication types

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

MeSH terms

  • Animals
  • Base Sequence
  • Blotting, Western
  • Bone Marrow Transplantation
  • Cell Proliferation*
  • Chromatin Immunoprecipitation
  • Fluorescent Antibody Technique
  • Hematopoietic Stem Cells / cytology*
  • Hematopoietic Stem Cells / metabolism
  • Humans
  • Immunoprecipitation
  • Indoles / pharmacology
  • Leukemia, Myeloid, Acute / genetics
  • Leukemia, Myeloid, Acute / mortality
  • Leukemia, Myeloid, Acute / pathology*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Molecular Sequence Data
  • Mutation / genetics
  • Phosphorylation / drug effects
  • Precursor Cells, B-Lymphoid / cytology
  • Precursor Cells, B-Lymphoid / drug effects
  • Precursor Cells, B-Lymphoid / metabolism
  • Promoter Regions, Genetic / genetics
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11 / antagonists & inhibitors
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11 / physiology*
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • STAT5 Transcription Factor / genetics
  • STAT5 Transcription Factor / metabolism
  • Survival Rate
  • Tandem Repeat Sequences / genetics*
  • Triazoles / pharmacology
  • bcl-X Protein / genetics
  • bcl-X Protein / metabolism
  • fms-Like Tyrosine Kinase 3 / genetics
  • fms-Like Tyrosine Kinase 3 / metabolism*

Substances

  • 3-(1-(3-(biphenyl-4-ylamino)-3-oxopropyl)-1H-1,2,3-triazol-4-yl)-6-hydroxy-1-methyl-2-phenyl-1H-indole-5-carboxylic acid
  • BCL2L1 protein, human
  • Indoles
  • RNA, Messenger
  • STAT5 Transcription Factor
  • Triazoles
  • bcl-X Protein
  • FLT3 protein, human
  • fms-Like Tyrosine Kinase 3
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11