Chromosomal translocations of the Mixed Lineage Leukemia 1 (MLL1) gene that result in expression of MLL fusion proteins are found in about 10% of acute leukemias affecting both children and adults. Patients harboring MLL fusions have very poor prognosis, with only ~35% five-year survival rate, implying the need for development of new therapies. The MLL fusion proteins retain the N-terminal fragment of MLL, while the C- terminal portion is replaced by one out of 60 fusion partners leading to a variety of MLL fusions. Importantly, all MLL fusion proteins interact with menin, a protein encoded by the Multiple Endocrine Neoplasia 1 (MEN1) gene, and the menin-MLL fusion protein interaction is critical to the oncogenic activity of MLL fusions in leukemia. Indeed, the menin-MLL interaction has been validated in the pre-clinical models as a valuable molecular target for development of new therapies for MLL leukemia. We hypothesize that inhibition of the menin-MLL fusion protein interaction by small molecules should reverse oncogenic activity of MLL fusion proteins and inhibit progression of MLL leukemia in vivo, resulting in a new targeted therapy for MLL leukemia patients. To this end we developed small molecule inhibitors of the menin-MLL inhibitors, which represent the first small molecules reported to block this protein-protein interaction. These compounds directly binding to menin at the MLL binding site and strongly inhibit the menin-MLL interaction. We substantially optimized both potency and drug-like properties of these compounds, resulting in very potent menin-MLL inhibitors (IC50 < 15 nM, Kd < 10 nM). In MLL leukemia cells, these compounds selectively inhibit proliferation, induce differentiation and downregulate expression of MLL fusion target genes at nanomolar concentrations. Importantly, the menin- MLL inhibitors we developed (e.g. MI-503, MI-463) markedly block progression of leukemia in vivo in mice models of MLL leukemia. In this project we will continue optimization of menin-MLL inhibitors to further improve their potency and drug-like properties with the goal to develop compounds with very strong in vivo efficacy in aggressive models of MLL leukemia, including patient derived xenografts (PDX). We will also study optimal combinations of menin-MLL inhibitors with selected chemotherapy and targeted agents to identify the best combinations for future clinical studies. Furthermore, we will investigate whether resistance develops to the treatment with menin-MLL inhibitors. This work should result in very potent and selective menin-MLL inhibitors that may provide a novel therapeutic approach for the treatment of MLL leukemia patients.
We are proposing to develop small molecules that block oncogenic potential of MLL fusion proteins in leukemia and assess their efficacy in advanced models of MLL leukemia. Ultimately, such compounds could be used as highly specific drugs for treatment of patients with aggressive forms of leukemia, which poorly respond to current therapies.
|Serio, J; Ropa, J; Chen, W et al. (2018) The PAF complex regulation of Prmt5 facilitates the progression and maintenance of MLL fusion leukemia. Oncogene 37:450-460|
|Kempinska, Katarzyna; Malik, Bhavna; Borkin, Dmitry et al. (2018) Pharmacologic Inhibition of the Menin-MLL Interaction Leads to Transcriptional Repression of PEG10 and Blocks Hepatocellular Carcinoma. Mol Cancer Ther 17:26-38|
|Borkin, Dmitry; Klossowski, Szymon; Pollock, Jonathan et al. (2018) Complexity of Blocking Bivalent Protein-Protein Interactions: Development of a Highly Potent Inhibitor of the Menin-Mixed-Lineage Leukemia Interaction. J Med Chem 61:4832-4850|
|Svoboda, Laurie K; Bailey, Natashay; Van Noord, Raelene A et al. (2017) Tumorigenicity of Ewing sarcoma is critically dependent on the trithorax proteins MLL1 and menin. Oncotarget 8:458-471|
|Jedwabny, Wiktoria; K?ossowski, Szymon; Purohit, Trupta et al. (2017) Theoretical models of inhibitory activity for inhibitors of protein-protein interactions: targeting menin-mixed lineage leukemia with small molecules. Medchemcomm 8:2216-2227|
|Sundaresan, Sinju; Meininger, Cameron A; Kang, Anthony J et al. (2017) Gastrin Induces Nuclear Export and Proteasome Degradation of Menin in Enteric Glial Cells. Gastroenterology 153:1555-1567.e15|
|Gray, Felicia; Cho, Hyo Je; Shukla, Shirish et al. (2016) BMI1 regulates PRC1 architecture and activity through homo- and hetero-oligomerization. Nat Commun 7:13343|
|He, S; Malik, B; Borkin, D et al. (2016) Menin-MLL inhibitors block oncogenic transformation by MLL-fusion proteins in a fusion partner-independent manner. Leukemia 30:508-13|
|Borkin, Dmitry; Pollock, Jonathan; Kempinska, Katarzyna et al. (2016) Property Focused Structure-Based Optimization of Small Molecule Inhibitors of the Protein-Protein Interaction between Menin and Mixed Lineage Leukemia (MLL). J Med Chem 59:892-913|
|Rogawski, David S; Grembecka, Jolanta; Cierpicki, Tomasz (2016) H3K36 methyltransferases as cancer drug targets: rationale and perspectives for inhibitor development. Future Med Chem 8:1589-607|
Showing the most recent 10 out of 24 publications