(Z)-Orantinib ((Z)-SU6668) is a potent, selective, orally active and ATP competitive inhibitor of Flk‐1/KDR, PDGFRβ, and FGFR1, with IC50s of 2.1, 0.008, and 1.2 µM, respectively. (Z)-Orantinib is a potent antiangiogenic and antitumor agent that induces regression of established tumors[1][2].
SU6668 (5-15 min) inhibits Flk-1 trans-phosphorylation (Ki=2.1 μM), FGFR1 trans-phosphorylation (Ki=1.2 μM), and PDGFR autophosphorylation (Ki=0.008 μM)[1].SU6668 (0.03-10 μM; 60 min) inhibits the VEGF-stimulated increase of KDR tyrosine phosphorylation in HUVECs[1].SU6668 inhibits mitogenesis of HUVECs induced by both VEGF and FGF in a dose-dependent manner with IC50s of 0.34 and 9.6 μM, respectively[1].
SU6668 (4-200 mg/kg/day; p.o. for 21 d) induces dose-dependent inhibition of A431 tumor growth in athymic mice[1].SU6668 (75 mg/kg/day; i.p. for 22 d) significantly suppresses tumor angiogenesis and vascularization in mice[1].SU6668 (200 mg/kg/day; p.o. for 11-27 d) induces striking regression of large established A431 xenografts in athymic mice[1].
[1]. Laird AD, et, al. SU6668 is a potent antiangiogenic and antitumor agent that induces regression of established tumors. Cancer Res. 2000 Aug 1;60(15):4152-60.
[2]. Laird ad, et, al. SU6668 inhibits Flk-1/KDR and PDGFRbeta in vivo, resulting in rapid apoptosis of tumor vasculature and tumor regression in mice. FASEB J. 2002 May;16(7):681-90.