Figure 1. Inhibition of VEGF₁₆₅ expression in cultured cells by pSilencer^siVEGFA: Shown is a gel image of a PCR product of VEGF isoforms. Vascular endothelial growth factor (VEGF)₁₂₁, VEGF₁₆₅, and VEGF₁₈₉ mRNA levels were determined by RT–PCR. The lanes are marked as follows: 1) pSilencer^siVEGF-transfected cells; 2) pSilencer null vector-transfected cells; and 3) nontransfected cells. B: The levels of VEGF isoforms were quantitated by densitometry and normalized by β-actin mRNA levels. C: VEGF₁₆₅ levels in the conditioned media were measured by ELISA kits and normalized to cell counts (1×10⁵). In a comparison with control cells, hypoxia-induced VEGF₁₆₅ mRNA and secreted VEGF₁₆₅ expression were found to be decreased after transfection with pSilencer^siVEGF, while VEGF₁₂₁ and VEGF₁₈₉ were expressed to a similar degree regardless of whether pSilencer^siVEGF was administered. Asterisk indicates p<0.05 compared to the control cells.