KIT and acute promyelocytic leukemia: In line with this notion, cell-sorting and syngeneic transplantation experiments in the mouse APL model showed that the leukemia-initiating potential of APL cells declined step-wisely along with a potential myeloid differentiation-like process from c-Kit+CD11b− AA4.1++ APL cells through c-Kit+CD11b++ APL cells towards c-Kit-CD11b++ APL cells (Figures 4a–c).