Cytotoxicity assays for CEP-701, PKC412, and CGP52421. MTT assays were performed on 10 primary AML samples, 5 with FLT3/ITD mutations and 5 with wild-type FLT3. (A-C) FLT3/ITD samples tested against increasing concentrations of CEP-701, PKC412, and CGP52421. (E-G) Samples with wild-type FLT3 tested against increasing concentrations of CEP-701, PKC412, and CGP52421. (D) Four dose-response curves are shown. Three represent the combined results of the values obtained in the experiments shown in panels A-C for the 3 drugs CEP-701, PKC412, and CGP52421 as single agents (error bars depict SEM). The fourth curve, which virtually overlaps the CGP52421 curve, represents the results when these same samples were exposed to an increasing concentration of CGP52421 in the presence of a fixed concentration of PKC412 (10 nM) so as to mimic the presence of both compounds found in plasma simultaneously. (H) As in panel D, using wild-type FLT3 samples.