Dose-dependent effect of imatinib mesylate on Akt dephosphorylation in Ba/F3p210^Bcr-Abl, Ba/F3p210^E255K, and Ba/F3p210^T315I cells. (A) Bcl-Abl expression versus phospho-Thr³⁰⁸ Akt levels in 32D, Ba/F3, Ba/F3p210^Bcr-Abl (WT), Ba/F3p210^E255K (E225K), and Ba/F3p210^T315I (T315I) cells. As shown, Akt phosphorylation is up-regulated by Bcr-Abl irrespective of mutations. (B, left) Dose-dependent effect of imatinib mesylate on Akt Thr³⁰⁸ phosphorylation (p-Thr³⁰⁸-Akt) in the 3 cell lines after 36-hour exposure. All immunoblots are representative of 3 independent experiments. (B, right) Bars represent the means of relative p-Akt level compared with the DMSO control of 3 independent determinations ± SD. According to the Jonckheere-Terpstra test, the trend P values were .004 and .022 for E225K and T315I, respectively.