Project description:Using mouse and human models of NUP98-rearrranged leukemia, we demonstrate that inhibition of MLL-Menin impairs leukemogenic gene expression and disrupts chromatin binding of MLL1 and NUP98 fusion proteins at a critical subset of genes that is essential for sustaining the undifferentiated leukemia phenotype.
Project description:Using mouse and human models of NUP98-rearrranged leukemia, we demonstrate that inhibition of MLL-Menin impairs leukemogenic gene expression and disrupts chromatin binding of MLL1 and NUP98 fusion proteins at a critical subset of genes that is essential for sustaining the undifferentiated leukemia phenotype.
Project description:Using mouse and human models of NUP98-rearrranged leukemia, we demonstrate that inhibition of MLL-Menin impairs leukemogenic gene expression and disrupts chromatin binding of MLL1 and NUP98 fusion proteins at a critical subset of genes that is essential for sustaining the undifferentiated leukemia phenotype.
Project description:To investigate the effect of Menin inhibitor on patient-derived NUP98-r AML. We treated primary AML cells with Menin inhibitor in a Mesenchymal stem cell co-Culture platform. Then we charachterized global gene expression in treated AML cells upon treatment in two different time points, day7 and day12.
Project description:Inhibition of the Menin (encoded by MEN1) and MLL1 (KMT2A) protein-protein interaction has been proposed as a potential targeted therapeutic strategy for MLL-rearranged (MLL-r) leukemia. We sought to develop more potent and selective Menin-MLL1 interaction inhibitors that are effective in vitro and in vivo to directly assess potential therapeutic opportunities. Structure-based design yielded the potent, highly selective and orally-bioavailable small molecule inhibitor VTP-50469. Human cell lines carrying MLL-rearrangements were highly sensitive and selectively responsive to treatment with VTP-50469. VTP-50469 displaced Menin from high molecular weight protein complexes and inhibited chromatin occupancy of MLL1 at select target genes. Loss of MLL1 binding led to specific changes in gene expression, cellular differentiation, and apoptosis. Mice engrafted with leukemia cells isolated from patients with either MLL-r AML or MLL-r ALL showed dramatic reductions of leukemia burden and prolonged survival when treated with VTP-50469. Remarkably, multiple mice engrafted with MLL-r ALL remained disease free greater than 1 year following cessation of treatment. Therefore, inhibition of the Menin-MLL1 interaction with VTP-50469 is highly effective in patient-derived xenograft (PDX) models of human MLL-r AML and MLL-r ALL which supports rapid translation of this approach to clinical trials. This submission represents the scRNAseq component of the study.
Project description:The interaction of Menin (MEN1) and MLL (MLL1, KMT2A) is a dependency and potential therapeutic opportunity against NPM1 mutant (NPM1mut) and MLL-rearranged (MLL-r) leukemias. Concomitant activating driver mutations in the gene encoding the tyrosine kinase FLT3 occur in both leukemias and are particularly common in the NPM1mut subtype. Transcriptional profiling upon pharmacological inhibition of the Menin-MLL complex revealed specific changes in gene expression with downregulation of the MEIS1 transcription factor and its transcriptional target gene FLT3 being most pronounced. Combining Menin-MLL inhibition with specific small molecule kinase inhibitors of FLT3 phosphorylation resulted in a significantly superior reduction of phosphorylated FLT3 and transcriptional suppression of genes downstream to FLT3 signaling. The drug combination induced synergistic inhibition of proliferation as well as enhanced apoptosis and differentiation compared to single-drug treatment in models of human and murine NPM1mut and MLL-r leukemias harboring an FLT3 mutation. Primary AML cells harvested from patients with NPM1mut FLT3mut AML showed significantly better responses to combined Menin and FLT3 inhibition than to single-drug or vehicle control treatment, while AML cells with wildtype NPM1, MLL, and FLT3 were not affected by any of the two drugs. In vivo treatment of leukemic animals with MLL-r FLT3mut leukemia reduced leukemia burden significantly and prolonged survival compared to the single-drug and vehicle control groups. Our data suggest that combined Menin-MLL and FLT3 inhibition represents a novel and promising therapeutic strategy for patients with NPM1mut or MLL-r leukemia and concurrent FLT3 mutation.
Project description:Treatment of cells carrying MLL-rearrangements with VTP-50469 (specific Menin-MLL1 inhibitor) displaces Menin from high molecular weight complexes and chromatin genome-wide. Since VTP-50469 block Menin interaction with MLL1 we tested using chip-seq if treatment with VTP-50469 also displaces MLL1 or MLL-fusions from chromatin. We found that the VTP-50469 treatment displaced MLL-fusions from only a subset of MLL-fusion binding sites. Since DOT1L is associated with MLL-AF9 we then tested if displacement of MLL1 also leads to loss of DOT1L association with chromatin on MLL-AF9 binding sites. We found that DOT1L binds to thousands of genes, treatment with VTP-50469 leads to genome wide loss of DOT1L binding including the same subset of MLL-fusion binding sites.