Design, molecular docking, in vitro, and in vivo studies of new quinazolin-4(3H)-ones as VEGFR-2 inhibitors with potential activity against hepatocellular carcinoma.

A series of new VEGFR-2 inhibitors were designed, synthesized and evaluated for their anti-proliferative activities against hepatocellular carcinoma (HepG-2 cell line). Compound 29 (IC = 4.33 ± 0.2 µg/ml) was found to be the most potent derivative as it has showed to be more active than doxorubicin (IC = 4.50 ± 0.2 µg/ml) and 78% of sorafenib activity (IC = 3.40 ± 0.25 µg/ml). The inhibitory profiles against VEGFR-2 were also assessed for the most promising candidates (16, 20, 22, 24, 24, 28, 28 29, 29 and 29). Compounds 29, 29 and 29 exhibited potent inhibitory activities towards VEGFR-2 at IC values of 3.1 ± 0.04, 3.4 ± 0.05 and 3.7 ± 0.06 µM, respectively, comparing sorafenib (IC = 2.4 ± 0.05 µM). Furthermorer, compound 29 induced apoptosis and arrested the cell cycle growth at G2/M phase. Additionally, in vivo antitumor experiments revealed that compounds 29 and 29 have significant tumor growth inhibition. The test of immuno-histochemical expression of activated caspase-3 revealed that there is a time-dependent increase in cleaved caspase-3 protein expression upon exposure of HepG-2 cells to compound 29. Moreover, the fibroblastic proliferative index test revealed that compound 29 could attenuate liver fibrosis. Docking studies also supported the results concluded from the biological screening via prediction of the possible binding interactions of the target compounds with VEGFR-2 active sites using the crystal structure of VEGFR-2 downloaded from the Protein Data Bank, (PDB ID: 2OH4) using Discovery Studio 2.5 software. Further structural optimization of the most active candidates may serve as a useful strategy for getting new lead compounds in search for powerful and selective antineoplastic agents.