Nintedanib Targets KIT D816V Neoplastic Cells Derived from Induced Pluripotent Stem cells of Systemic Mastocytosis

Abstract

223 words Introduction 533 words = 3995 words Methods 375 words Results 2382 words References 49 references Key Points • Patient-derived KIT D816V iPSCs and CRISPR-engineered KIT D816V ESCs model SM disease heterogeneity and serve as drug screening platform • Nintedanib selectively targets KIT D816V iPSC-and ESC-derived cells and primary samples of SM patients Primary Scientific Category: Myeloid neoplasia Abstract The KIT D816V mutation is found in more than 80% of patients with systemic mastocytosis (SM) and is key to neoplastic mast cell (MC) expansion and accumulation in affected organs. KIT D816V therefore represents a prime therapeutic target for SM. Here we generated a panel of patient-specific KIT D816V induced pluripotent stem cells (iPSCs) from patients with aggressive SM (ASM) and mast cell leukemia (MCL) to develop a patient-specific SM disease model for mechanistic and drug discovery studies. KIT D816V iPSCs differentiated into neoplastic hematopoietic progenitor cells and MCs with patient-specific phenotypic features, thereby reflecting the heterogeneity of the disease. CRISPR/Cas9n-engineered KIT D816V human embryonic stem cells (ESCs), when differentiated into hematopoietic cells, recapitulated the phenotype observed for KIT D816V iPSC hematopoiesis. KIT D816V causes constitutive activation of the KIT tyrosine kinase receptor and we exploited our iPSCs and ESCs to investigate new tyrosine kinase inhibitors targeting KIT D816V. Our study identified nintedanib as a novel KIT D816V inhibitor. Nintedanib selectively reduced the viability of iPSC-derived KIT D816V hematopoietic progenitor cells and MCs in the nanomolar range. Nintedanib was also active on primary samples of KIT D816V SM patients. Molecular docking studies show that nintedanib binds to the ATP binding pocket of inactive KIT D816V. Our results suggest nintedanib as a new drug candidate for KIT D816V targeted therapy of advanced SM.

The spatial self-organization within pluripotent stem cell colonies is continued in detaching aggregates

“…Five human iPSC-lines were generated from mesenchymal stromal cells (iPSC-102, iPSC-104, and iPSC-106) or blood (PT4-WT4, PT18-WT18; Toledo et al, 2020) by reprogramming with episomal plasmids or sendai virus, respectively. The study was approved by the local ethic committee and all samples were taken after written consent (EK206/09).…”