Antitumor activity of S116836, a novel tyrosine kinase inhibitor, against imatinib-resistant FIP1L1-PDGFR?-expressing cells.

ABSTRACT: The FIP1-like-1-platelet-derived growth factor receptor alpha (FIP1L1-PDGFR?) fusion oncogene is the driver factor in a subset of patients with hypereosinophilic syndrome (HES)/chronic eosinophilic leukemia (CEL). Most FIP1L1-PDGFR?-positive patients respond well to the tyrosine kinase inhibitor (TKI) imatinib. Resistance to imatinib in HES/CEL has been described mainly due to the T674I mutation in FIP1L1-PDGFR?, which is homologous to the imatinib-resistant T315I mutation in BCR-ABL. Development of novel TKIs is imperative to overcome resistance to imatinib. We synthesized S116836, a novel TKI. In this study, we evaluated the antitumor activity of S116836 in FIP1L1-PDGFR?-expressing cells. The results showed that S116836 potently inhibited PDGFR? and its downstream signaling molecules such as STAT3, AKT, and Erk1/2. S116836 effectively inhibited the growth of the WT and T674I FIP1L1-PDGFR?-expressing neoplastic cells in vitro and in nude mouse xenografts. Moreover, S116836 induced intrinsic pathway of apoptosis as well as the death receptor pathway, coincided with up-regulation of the proapoptotic BH3-only protein Bim-EL through the Erk1/2 pathway. In conclusion, S116836 is active against WT and T674I FIP1L1-PDGFR?-expressing cells, and may be a prospective agent for the treatment of HES/CEL.

SUBMITTER: Shen Y 

PROVIDER: S-EPMC4279382 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature