Leukemogenic Ptpn11 causes fatal myeloproliferative disorder via cell-autonomous effects on multiple stages of hematopoiesis.

Abstract

PTPN11, which encodes the tyrosine phosphatase SHP2, is mutated in approximately 35% of patients with juvenile myelomonocytic leukemia (JMML) and at a lower incidence in other neoplasms. To model JMML pathogenesis, we generated knockin mice that conditionally express the leukemia-associated mutant Ptpn11(D61Y). Expression of Ptpn11(D61Y) in all hematopoietic cells evokes a fatal myeloproliferative disorder (MPD), featuring leukocytosis, anemia, hepatosplenomegaly, and factor-independent colony formation by bone marrow (BM) and spleen cells. The Lin(-)Sca1(+)cKit(+) (LSK) compartment is expanded and "right-shifted," accompanied by increased stem cell factor (SCF)-evoked colony formation and Erk and Akt activation. However, repopulating activity is decreased in diseased mice, and mice that do engraft with Ptpn11(D61Y) stem cells fail to develop MPD. Ptpn11(D61Y) common myeloid progenitors (CMPs) and granulocyte-monocyte progenitors (GMPs) produce cytokine-independent colonies in a cell-autonomous manner and demonstrate elevated Erk and Stat5 activation in response to granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation. Ptpn11(D61Y) megakaryocyte-erythrocyte progenitors (MEPs) yield increased numbers of erythrocyte burst-forming units (BFU-Es), but MEPs and erythrocyte-committed progenitors (EPs) produce fewer erythrocyte colony-forming units (CFU-Es), indicating defective erythroid differentiation. Our studies provide a mouse model for Ptpn11-evoked MPD and show that this disease results from cell-autonomous and distinct lineage-specific effects of mutant Ptpn11 on multiple stages of hematopoiesis.

• Authors: Gordon Chan, Demetrios Kalaitzidis, Tatiana Usenko, Jeffery L Kutok, Wentian Yang, M Golam Mohi, Benjamin G Neel
• Journal: Blood (Blood) Vol. 113 Issue 18 Pg. 4414-24 (Apr 30 2009) ISSN: 1528-0020 [Electronic] United States
• PMID: 19179468 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• STAT5 Transcription Factor
• Granulocyte-Macrophage Colony-Stimulating Factor
• Mitogen-Activated Protein Kinase 1
• Mitogen-Activated Protein Kinase 3
• Cre recombinase
• Integrases
• Protein Tyrosine Phosphatase, Non-Receptor Type 11
• Ptpn11 protein, mouse

Topics

• Adoptive Transfer
• Animals
• Bone Marrow (metabolism, pathology)
• Cell Differentiation
• Cell Proliferation
• Cells, Cultured
• Colony-Forming Units Assay
• Erythrocytes (metabolism, pathology)
• Erythroid Precursor Cells (metabolism, pathology)
• Female
• Flow Cytometry
• Gene Knock-In Techniques
• Genes, Lethal (physiology)
• Granulocyte-Macrophage Colony-Stimulating Factor (pharmacology)
• Granulocyte-Macrophage Progenitor Cells (metabolism, pathology)
• Granulocytes (metabolism, pathology)
• Hematopoiesis (physiology)
• Hematopoietic Stem Cells (metabolism, pathology)
• Integrases (metabolism)
• Male
• Mice
• Mice, Inbred C57BL
• Mitogen-Activated Protein Kinase 1 (metabolism)
• Mitogen-Activated Protein Kinase 3 (metabolism)
• Monocytes (metabolism, pathology)
• Myeloproliferative Disorders (etiology, metabolism, pathology)
• Phenotype
• Protein Tyrosine Phosphatase, Non-Receptor Type 11 (physiology)
• STAT5 Transcription Factor (metabolism)
• Spleen (metabolism, pathology)