Acute myeloid leukemia (AML) is genetically complex, but patients can be divided into those with chromosomal translocations and those that are cytogenetically normal (CN-AML). CN-AML represents nearly 50 percent of human AML cases, and the overall five-year survival for adults with CN-AML is approximately 30 percent.
Mutations in the de novo DNA methyltransferase DNMT3A and internal tandem duplications of the FMS-like tyrosine kinase 3 (FLT3-ITD) are two of the most frequent events in CN-AML.
Moreover, recent whole-genome sequencing of CN-AML patient samples identified:
- High-frequency co-occurrence of FLT3 and DNMT3A mutations
- Corresponding changes to the risk classification for these CN-AML patients to a poorer prognosis
Because human epidemiologic studies cannot easily control for factors that confer disease risk, genetically engineered mouse (GEM) strains provide essential tractable platforms to mechanistically dissect disease pathobiology, heterogeneity and therapeutic response.
Although neither Flt3-ITD nor inducible deletion of Dnmt3a induces spontaneous leukemia in mice, when we combined Flt3-ITD mutant alleles with inducible deletion of Dnmt3a, we find a spontaneous, rapidly lethal, completely penetrant, and transplantable AML.
We hypothesize that inducible deletion of Dnmt3a in Flt3-ITD mice produces a faithful model of human CN-AML that can be used to infer essential biological and molecular factors that constitute therapeutic response.
To this end, we propose, genomic, cytogenetic and single-cell molecular analyses (with comparison to primary human CN-AML) to deconvolute both the tumor architecture and the underlying cellular states.
We expect the proposed research to deliver a validated murine model of FLT3-ITD / DNMT3a-mutant CN-AML with defined translational utility.