In vitro study | ARQ-197 inhibits HGF/c-met-induced cellular responses. ARQ-197 has antitumor activity, inhibiting A549, DBTRG and NCI-H441 cell proliferation with IC50 of 0.38, 0.45, 0.29 μm, respectively. Treatment with ARQ-197 leads to decreased phosphorylation in the MAPK signaling cascade and blocks invasion and migration. In addition, c-Met is aberrantly expressed in NCI-H661 cells without endogenous c-Met expression, forming an invasion phenotype that is also ARQ-197 repressed. The addition of increasing concentrations of ARQ-197 did not significantly affect the K m value of ATP, but treatment of c-Met with 0.5 μm ARQ-197 reduced the V max value of c-Met by a factor of 3. ARQ-197 reducing the K m value of V max without affecting ATP indicates that the ARQ-197 inhibition c-Met is non-ATP competitive inhibition, and also indicates that ARQ-197 has high kinase selectivity. ARQ-197 inhibits human recombination c-Met with a constant K I value of 355 nM. Although the highest concentration of used ATP is 200 μm, when the concentration of ATP is 1 mM, the ARQ-197 inhibitory c-Met effect does not decrease. ARQ-197 inhibits c-Met phosphorylation and blocks downstream c-Met signaling pathways. ARQ-197 blocks constitutive and ligand-regulated c-Met autophosphorylation, by enhancing c-Met activity, which in turn inhibits downstream c-Met effectors. ARQ-197 acts on c-Met-expressing human cancer cells, including HT29, MKN-45, and MDA-MB-231 cells, to induce caspase-dependent apoptosis. |
In vivo study | ARQ-197 treatment of HT29,MKN-45, and MDA-MB-231 three xenograft models reduced tumor growth rates by 66%,45%, and 79%, respectively. Oral administration of the three xenograft models at a dose of 200 mg/kg ARQ-197 showed no significant change in body weight. In terms of pharmacodynamics, ARQ-197 acts on the human colon Transplant tumor HT29 and strongly inhibits c-Met phosphorylation, ARQ-197 c-Met autophosphorylation is strongly reduced after 24 hours of oral administration at a dose of 200 mg/kg alone. In conclusion, ARQ-197 inhibited human c-Met-dependent xenograft growth. |