Ki8751

Kinase experiment:

VEGFR-2 kinase assay is described below; GST-fusion proteins of KDR (Flk-1: cytoplasmic domain) are produced in the baculo-virus expression system. GST-KDR is premixed with a serial dilution of Ki8751 in the kinase buffer. The kinase reaction is initiated by the addition of 2 µM ATP in a solution of MnCl2. After 20 min incubation at room temperature, the reaction is stopped with an addition of EDTA. Phosphorylation levels of GST-KDR are detected by immunoblotting with anti-phosphotyrosine monoclonal antibodies (PY20) and detected by ECL fluorography[1].

Cell experiment:

HUVECs are placed at a density of 4000 cells/200 µL/well on collagene type I precoated 96-well plates in M199 medium with 5% fetal bovine serum (FBS). After 24 h, the cells are incubated for 1 h in the presence or absence of Ki8751; then the cells are stimulated by rhVEGF (20 ng/mL). The cultures are incubated at 37 °C for 72 h, then pulsed with 1 µCi/well [3H]thymidine and reincubated for 14 h. Cells are assayed for the incorporation of tritium using a beta counter[1].

Animal experiment:

Mice: The effects of Ki8751 on tumor growth is tested against various tumors, human stomach carcinoma (St-4), human lung carcinoma (LC-6), human colon carcinoma (DLD-1) and human melanoma (A375), using human tumor xenografts in nude mice. Ki8751 is administered orally to mice in the experimental groups once a day for 9 consecutive days at 5 mg/kg, and the vehicle is administered to control animals. Tumor volumes are monitored twice weekly[1].

References:

[1]. Kubo K, et al. Novel potent orally active selective VEGFR-2 tyrosine kinase inhibitors: synthesis, structure-activity relationships, and antitumor activities of N-phenyl-N'-{4-(4-quinolyloxy)phenyl}ureas. J Med Chem, 2005, 48(5), 1359-1366.