EXOKV11 suppresses VEGF-induced endothelial proliferation and VE-cadherin phosphorylation. (A, C) Starved HUVECs were pretreated with EXO, KV11, or EXOKV11 for 24 h and then stimulated with 25 ng/mL VEGF for 10 min. Representative western blots for pERK (A) and pSrc (C) showing VEGF-downstream signaling. Conbercept (VEGF-trap) was used as a positive control, the pretreatment time was 5 min before VEGF stimulation. 30 μg total protein from each sample was loaded. (E) Starved HUVECs were pretreated with EXO, KV11, or EXOKV11 for 24 h and then stimulated with 25 ng/mL VEGF for 15 min. Representative western blot for phosphorylation of VE-cadherin at site Y685 showing how the indicated pretreatment affects VEGF-induced phosphorylation of VE-cadherin at Y685. Conbercept (VEGF-trap) was used as a positive control, the pretreatment time was 5 min. 30 μg total protein from each sample was loaded. (B, D, and F) Quantification of blots shown in (A), (C), and (E); n = 3 - 5 independent experiments. The data represent as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, one-way ANOVA followed by Tukey's multiple comparisons test in (B), (D), (F).