KIT and leukemia: In addition, Foxm1 KO markedly increased the frequency of early (Annexin V+DAPI−) or late apoptosis in Lin−c-kit+ (Annexin V+DAPI+) BM cells by 10-fold while it increased frequency of apoptosis of relatively mature myeloid cell (Lin−c-kit−) by 2-fold (Fig. 4b), suggesting that LSC-enriched leukemia cells are much more sensitive to absence of Foxm1 than mature leukemia cells.