Fetal and neonatal hematopoietic progenitors are functionally and transcriptionally resistant to Flt3-ITD mutations
- Washington University School of Medicine, United States
Abstract
The FLT3 Internal Tandem Duplication (FLT3ITD) mutation is common in adult acute myeloid leukemia (AML) but rare in early childhood AML. It is not clear why this difference occurs. Here we show that Flt3ITD and cooperating Flt3ITD/Runx1 mutations cause hematopoietic stem cell depletion and myeloid progenitor expansion during adult but not fetal stages of murine development. In adult progenitors, FLT3ITD simultaneously induces self-renewal and myeloid commitment programs via STAT5-dependent and STAT5-independent mechanisms, respectively. While FLT3ITD can activate STAT5 signal transduction prior to birth, this signaling does not alter gene expression until hematopoietic progenitors transition from fetal to adult transcriptional states. Cooperative interactions between Flt3ITD and Runx1 mutations are also blunted in fetal/neonatal progenitors. Fetal/neonatal progenitors may therefore be protected from leukemic transformation because they are not competent to express FLT3ITD target genes. Changes in the transcriptional states of developing hematopoietic progenitors may generally shape the mutation spectra of human leukemias.
Data availability
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FLT3-ITD has developmental context-specific effects on hematopoiesis and myeloid leukemia initiationPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE81153).
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Tet2-/-Flt3ITD and WT stem and progenitor cellsPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE57244).
Article and author information
Author details
Funding
U.S. Department of Defense (CA130124)
- Jeffrey A Magee
St. Baldrick's Foundation (Scholar Award)
- Jeffrey A Magee
Hyundai Hope On Wheels (Hope Scholar)
- Jeffrey A Magee
Gabrielle's Angel Foundation for Cancer Research (Medical Research Award)
- Jeffrey A Magee
Children's Discovery Institute of Washington University and St. Louis Children's Hospital (Faculty Scholar Award)
- Jeffrey A Magee
Eunice Kennedy Shriver National Institute of Child Health and Human Development (K12-HD076224)
- Jeffrey A Magee
Eunice Kennedy Shriver National Institute of Child Health and Human Development (5T32HD043010-12)
- Andrew S. Cluster
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mice were housed in the Department for Comparative Medicine at Washington University. All animals were handled and procedures were performed according to institutional animal care and use committee (IACUC) protocols 20130134 and 20160087. These protocols were approved by the Washington University Committees on the Use and Care of Animals.
Copyright
© 2016, Porter et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Fetal and neonatal hematopoietic progenitors are functionally and transcriptionally resistant to Flt3-ITD mutations
eLife 5:e18882.
https://doi.org/10.7554/eLife.18882
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