Differentiation therapy for murine myelofibrosis model with MLN8237 loaded low-density lipoproteins

Primary myelofibrosis (PMF) is a severe myeloproliferative neoplasm that is characterized by low-differentiation megakaryoblasts and progressive bone marrow fibrosis. Although an Aurora kinase A (AURKA) targeting small-molecule inhibitor MLN8237 has been approved in clinical trials for differentiation therapy of high-risk PMF patients, its off-target side effects lead to a partial remission and serious complications. Here, we report a dual-targeting therapy agent (rLDL-MLN) with great clinical translation potential for differentiation therapy of PMF disease. In particular, the reconstituted low-density lipoprotein (rLDL) nanocarrier and the loaded MLN8237 can actively target malignant hematopoietic stem/progenitor cells (HSPCs) via LDL receptors and intracellular AURKA, respectively. In contrast to free MLN8237, rLDL-MLN effectively prohibits the proliferation of PMF cell lines and abnormal HSPCs and significantly induces their differentiation, as well as prevents the formation of erythrocyte and megakaryocyte colonies from abnormal HSPCs. Surprisingly, even at a 1500-fold lower dosage (0.01 mg/kg) than that of free MLN8237, rLDL-MLN still exhibits a much more effective therapeutic effect, with the PMF mice almost clear of blast cells. More importantly, rLDL-MLN promotes hematological recovery without any toxic side effects at the effective dosage, holding great promise in the targeted differentiation therapy of PMF patients.