Fig. 2.

Increased expression of VEGF after HIF-1α and HIF-2α. (A) Cells were cotransfected with plasmid containing the full-length promoter of the VEGF gene driving luciferase expression (500 ng) and plasmid containing the LacZ gene (100 ng) as an internal control and after 24 h transduced with AdHIF-1α, AdHIF-2α, or AdGFP for the next 48 h. As shown by measurement of luciferase activity, both HIF-1α and HIF-2α activated VEGF transcription. (B) Real-time PCR and (C) ELISA were performed to examine the mRNA and protein level of VEGF, respectively, after 48 h of transduction with adenoviral vectors. Both HIF isoforms enhanced VEGF production, but the effect of HIF-2α was more potent. Each bar represents the mean ± SD of three to six independent experiments performed in duplicate. *p < 0.05, comparing AdGFP vs AdHIF-1α or AdHIF-2α, #p < 0.05, comparing AdHIF-1α vs AdHIF-2α.