We conclude that AMN107 and imatinib are active and equipotent against cells expressing the FIP1L1-PDGFR-alpha fusion gene..     ///    "Cumulative evidence indicates that the Bcr-Abl tyrosine kinase inhibitor imatinib mesylate (Gleevec) is active for the treatment of patients with HES, particularly those expressing the FIP1L1-PDGFR-alpha oncoprotein. "    ///    "In a subset of patients, this is caused by the FIP1L1-PDGFR-alpha fusion tyrosine kinase. "    ///    We tested the in vitro efficacy of imatinib and AMN107 in the EOL-1 cell line and in cells from a patient with HES harboring the FIP1L1-PDGFR-alpha fusion kinase. 