In vivo efficacy of xenotransplanted tumors with FLT3/ITD. (A-C) MOLM-13 cells (107 cells/mouse) were subcutaneously inoculated into SCID mice. Five days after inoculation, tumor volume was measured. The 25 mice with tumors ranging from 90 to 130 mm3 were selected 5 days after inoculation and divided into 5 groups. Mice (n = 5 in each group) were orally administered with vehicle or KW-2449 (2.5, 5.0, 10, and 20 mg/kg) twice a day for 14 days. (A) Tumor volume was measured twice a week during the treatment. Mean tumor volume ± SD is shown. KW-2449 showed potent and significant antitumor effect in a dose-dependent manner. (B) Relative ratio of tumor volume (V) to initial tumor volume (V0) was represented (V/V0). Relative V/V0 ratio of a drug-treated group compared with a control group was represented as T/C. (C) KW-2449 treatment at 20 mg/kg twice a day showed complete regression and disappearance of tumors in all mice.
