Interestingly, whereas CG-806 had low IC50s (i.e., 4 to 10 nM) in most human and murine FLT3-WT leukemia cell lines, its EC50s could not be determined in some human FLT3-WT leukemia cell lines, such as THP-1 and Kasumi-1 (Table 1). Here, FLT3 is linked to leukemia.