title: The new tyrosine-kinase inhibitor and anticancer drug dasatinib reversibly affects platelet activation in vitro and in vivo.
abstract: Dasatinib is an oral potent adenosine triphosphate (ATP)-competitive inhibitor of BCR-ABL, cKIT, platelet-derived growth factor receptor, and SRC family kinases (SFKs), which has demonstrated high efficiency in patients with imatinib-resistant chronic myelogenous leukemia. Here, we show that dasatinib weakly affects platelet activation by thrombin or adenosine diphosphate but is a potent inhibitor of platelet signaling and functions initiated by collagen or FcgammaRIIA cross-linking, which require immunoreceptor tyrosine-based activation motif phosphorylation by SFKs. Accordingly, dasatinib treatment rapidly decreases the volume of thrombi formed under arterial flow conditions in whole blood from patients or mice perfused over a matrix of collagen. Moreover, treatment of mice with dasatinib increases the tail bleeding time in a dose-dependent manner. Interestingly, these effects are rapidly reversible after interruption of the treatment. Our data clearly demonstrate that, in contrast to imatinib, dasatinib affects platelet functions in vitro and in vivo, which has important implications in clinic and could explain increased risks of bleeding observed in patients. Moreover, dasatinib efficiently prevents platelet activation mediated by FcgammaRIIA cross-linking and by sera from patients with heparin-induced thrombocytopenia, suggesting that reversible antiplatelet agents acting as ATP-competitive inhibitors of SFKs may be of therapeutic interest in the treatment of this pathology.
authors.affiliation: Département d'Oncogenèse, Signalisation et Innovation Thérapeutique, Université Toulouse III Paul Sabatier, Inserm U563, Centre de Physiopathologie de Toulouse Purpan, Toulouse, France.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Gratacap
authors.forename: Valérie
authors.initials: V
authors.lastname: Martin
authors.forename: Marie-Cécile
authors.initials: MC
authors.lastname: Valéra
authors.forename: Sophie
authors.initials: S
authors.lastname: Allart
authors.forename: Cédric
authors.initials: C
authors.lastname: Garcia
authors.forename: Pierre
authors.initials: P
authors.lastname: Sié
authors.forename: Christian
authors.initials: C
authors.lastname: Recher
authors.forename: Bernard
authors.initials: B
authors.lastname: Payrastre
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001549:Benzamides; D001792:Blood Platelets / Q000187:drug effects*; D000069439:Dasatinib; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D010879:Piperazines / Q000494:pharmacology; D015539:Platelet Activation / Q000187:drug effects*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D011743:Pyrimidines / Q000494:pharmacology*; D013844:Thiazoles / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D004791:Enzyme Inhibitors; D010879:Piperazines; D011743:Pyrimidines; D013844:Thiazoles; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D000069439:Dasatinib