Figure 5.

C-18 does not inhibit receptor tyrosine kinase (RTK) phosphorylation. (a) Human umbilical vein endothelial cells (HUVECs) were incubated with Ang-1 (250 μg ml⁻¹) for 5 min in the presence or absence of C-18 (10 μM; 30 min pretreatment). Cells were then lysed and the Tie2 receptor precipitated; after SDS–polyacrylamide gel electrophoresis (SDS–PAGE) and transfer, membranes were blotted with a phosphotyrosine Ab or a Tie2 antibody. Similar results were obtained when C-18 was used at 1 nM. (b) HUVECs were incubated with vascular endothelial growth factor (VEGF; 100 μg ml⁻¹) for 2 min with or without pretreatment of the indicated C-18 concentration. Cells lysates were analysed using total or phospho-specific (Tyr-1175) VEGFR2 antibodies. Blots shown are representative of experiments repeated twice with similar results. Ang, angiopoietin; C-18, 2-((1E,Z)-1-benzylidene-5-bromo-2-methyl-1H-inden-3-yl)acetic acid.