VEGF-shRNA downregulates expression of VEGF and Del1 in vitro. LS-174T cells were transfected with VEGF-shRNA and harvested 48 h later. (A) VEGF (upper row) and Del1 proteins (middle row) in lysates of untreated cells (lane 1) or cells transfected with control vector (lane 2), or VEGF-shRNA plasmid (lane 3) was Western blotted. The density of each band was measured and compared to that of the internal control β-actin (bottom row). (B, C) The expression of VEGF mRNA (200 bp) (B) or Del1 mRNA (350 bp) (C) was detected by RT-PCR in lysates of untreated LS-174T cells (lane 2) or cells transfected with control vector (lane 3), or Del1-shRNA plasmid (lane 4). GAPDH (500 bp) was amplified as a PCR internal control. Lane 1 denotes the DNA marker. * Indicates a significant difference at P < 0.05 in the band intensities compared to control.