Figure 5.

Modulation of vasohibin expression and the effect of vasohibin on VEGF-stimulated signaling in HUVECs. (A) Induction of vasohibin. HUVECs were stimulated with VEGF (1 nM), PlGF (1 nM), FGF-2 (2 nM), HGF (1 nM), TNF-α (1 nM), or 10% serum for 24 hours. Thereafter, total RNA was obtained and Northern blotting for vasohibin was performed. (B) Effect of TNF-α on the induction of vasohibin by VEGF. HUVECs were stimulated with VEGF (1 nM) and/or TNF-α (1 nM). Thereafter, Northern blotting and Western blotting for vasohibin were performed. (C) Effect of hypoxia on the induction of vasohibin by VEGF. HUVECs were stimulated with VEGF (1 nM) under normoxic (N) or hypoxic (H) conditions. Upper panel: Total RNA was obtained and real-time RT-PCR of vasohibin was performed. Values are expressed as mean ± SD of 4 samples. **P < 0.01. Lower panel: Cell extract was obtained and Western blotting for vasohibin was performed. (D) Effect of vasohibin on VEGF-mediated KDR tyrosine phosphorylation or ERK1/2 activation of HUVECs. HUVECs were infected with AdLacZ or AdKIAA at an MOI of 100, and then stimulated with VEGF (10 ng/ml). VEGF-mediated KDR tyrosine phosphorylation or ERK1/2 activation was analyzed. Results shown in lower panel indicate that AdKIAA increased the synthesis of vasohibin in an MOI-dependent manner. IP, immunoprecipitation; IB, immunoblotting; pKDR, phosphorylated KDR.