SGX-523 is a selective Met inhibitor (IC50: 4 nM), no inhibitory to Abl, BRAFV599E, p38α, and c-Raf.

MET:4 nM

SGX523, administered orally twice daily at a dose of ≥10 mg/kg, significantly delays the anticipated growth of GTL16 tumors. At a higher concentration of 30 mg/kg, SGX523 not only markedly inhibits the growth of U87 mg tumors but also delays the growth of H441 tumors, while reducing the levels of MET autophosphorylation.

SGX523, at nanomolar concentrations, inhibits MET-regulated signaling, cell proliferation, and migration without affecting signals dependent on other protein kinases, such as RON, even at micromolar levels. In vivo, SGX523 dose-dependently inhibits the growth of xenografts derived from human malignant gliomas, lung cancer, and gastric cancer, indicating these tumors' reliance on MET's catalytic activity. SGX-523 acts as a c-Met/hepatocyte growth factor receptor tyrosine kinase inhibitor, deactivating MET and preventing its interaction with other protein kinases. It significantly inhibits the catalytic domain of purified MET while having no effect on closely related RON. As an ATP-competitive inhibitor, SGX523 shows a higher affinity for low-activity and non-phosphorylated MET (MET-KD(0P), Ki: 2.7 nM).

Kinase assays: Initial rate constants are measured at 21 °C in the presence of 100 mM HEPES (pH 7.5), 0.3 mg/mL poly(Glu-Tyr) peptide substrate, 10 mM MgCl2, 1 mg/mL bovine serum albumin, 5% DMSO, 20 nM MET-KD and various concentrations of ATP and SGX523. Total reaction volumes (20 μL) are quenched with 20 μL Kinase-Glo detection buffer. Luminescence is detected in a plate-reading luminometer and the results are analyzed by nonlinear regression.

MDCK cells are seeded at 1 × 103 per well in a 24-well plate and incubated at 37 °C in 5% CO2 for 1 week in MEM and 10% fetal bovine serum. HGF (90 ng/mL) and various concentrations of SGX523 are added and the cells are incubated for another 18 hours (37 °C, 5% CO2 humidified incubator) and visualized. A549 cells are plated in 12-well plates (6 × 104 per well) and incubated to confluence to investigate cell migration. A channel is introduced into the monolayers by scratching with a pipette tip. Various dilutions of compound are added in starve medium in the presence and absence of HGF (90 ng/mL).The wells are checked for cell migration after twenty-fou(Only for Reference)