An alternative Abl-kinase inhibitor overcomes imatinib resistance in cells expressing mutant forms of Bcr-Abl

Background and objective: The tyrosinkinase inhibitor Imatinib is active in Philadelphia-positive (Ph+) leukemia. Mutations within the Bcr-Abl kinase domain represent the major cause for clinical resistance toward imatinib. We aimed to examine, whether the alternative Abl Kinaseinhibitor SKI-DV 243 may be capable of suppressing the growth of cells expressing mutant forms of Bcr-Abl. Methods: The proliferation of cells expressing wild-type and mutant forms of Bcr-Abl was measured in the presence of imatinib or the pyrido-pyrimidine SKI-DV 2-43. Results: The growth of a cell line expressing wild-type Bcr-Abl was suppressed with higher potency in the presence of SKI-DV 2-43 when compared to imatinib. Moreover, SKI-DV 2-43 effectively suppressed mutant forms of Bcr-Abl that cause imatinib resistance in patients. Conclusion: Therefore, alternative Abl kinase inhibitors might play an important role in the future therapy of Philadelphiapositive leukemias.