Firstly, we surprisingly found that CD117-positive leukemia stem-like cells (GFP+CD117+CD11b+/low) have a 20-fold higher percentage in MA-induced FGFR3-knockout leukemia cells (MA-KO) than in MA-induced WT leukemia cells (MA-WT) (Figure 1A). This evidence concerns the gene KIT and leukemia.