Corosolic acid reduces VEGFR2 kinase activity.

(A) Huh7 cells were treated with 0.1% DMSO (control) or corosolic acid for 15 min and lysates were immunoprecipitated with anti-VEGFR1, VEGFR2, and VEGFR3 Ab, followed by blotting with anti-phospho-tyrosine Ab. (For VEGFR2, n = 3, ***P < 0.001 compared with the DMSO treated group) (B) ADP-Glo Kinase Assay (Promega, Madison, USA) was performed to assess the inhibitory effect of corosolic acid on VEGFR2 kinase activity. (n = 3, RLU data were normalized to the control group and shown as percentages) (C) Huh7 cells were transfected with 100 nM KDR siRNA or control siRNA, recovered for 24 h, and treated with 0.1% DMSO (control) or CA. Migration activity was assessed with a transwell assay. (n = 3, **P < 0.01, ***P < 0.001 compared with the DMSO treated cells in Huh7 control siRNA group)