MP-470 is a potent and multi-targeted inhibitor of c-Kit, PDGFRα and Flt3 with IC50 of 10 nM, 40 nM and 81 nM, respectively.
The hydrochloride salt of MP-470 also inhibits several mutants of c-Kit, including c-KitD816V, c-KitD816H, c-KitV560G, and c-KitV654A, as well as a Flt3 mutant (Flt3D835Y) and two PDGFRα mutants (PDGFRαV561D and PDGFRαD842V), with IC50 of 10 nM to 8.4 μM. MP-470 potently inhibits the proliferation of OVCAR-3, A549, NCI-H647, DMS-153, and DMS-114 cells, with IC50 of 0.9 μM–7.86 μM.MP-470 also inhibits c-Kit and PDGFRα, with IC50 values of 31 μM and 27 μM, respectively. MP-470 demonstrates potent cytotoxicity against MiaPaCa-2, PANC-1, and GIST882 cells, with IC50 of 1.6 μM to 3.0 μM. MP-470 also binds to and inhibits several c-Kit mutants, including c-KitK642E, c-KitD816V, and c-KitK642E/D816V.In MDA-MB-231 cells, MP-470 (1 μM) inhibits tyrosine phosphorylation of AXL.In LNCaP and PC-3, but not DU145 cells, MP-470 exhibits cytotoxicity with IC50 of 4 μM and 8 μM, respectively, and induces apoptosis at 10 μM. In LNCaP cells, MP-470 (10 μM) elicits G1 arrest and decreases phosphorylation of Akt and ERK1/2.In SF767 cells, MP-470 (10 μM) inhibits c-Met phosphorylation and sensitizes cells to radiation. In combination with radiation, MP-470 (10 μM) inhibits glycogen synthase kinase (GSK)3β activity, induces apoptosis, and disrupts the repair of dsDNA breaks probably through suppression of Rad51.
In mice xenograft models of HT-29, A549, and SB-CL2 cells, MP-470 (10 mg/kg–75 mg/kg via i.p. or 50 mg/kg–200 mg/kg via p.o.) inhibits tumor growth.In mice bearing LNCaP xenograft, MP-470 (20 mg/kg) combined with Erlotinib significantly induces tumor growth inhibition (TGI). |
