Inhibitory effects of antisense oligonucleotides on VEGF gene expression by human hepatocellular carcinoma cells

Objective To investigate the inhibitory effects of antisense oligonucleotides to different sequences on VEGF gene expression by human hepatoma cells. Methods SMMC7721 cells were cultured under normoxic or hypoxic conditions for 24 h, followed by being transfected with different antisense oligonucleotides (A06513 to cap structure, A06514 to translation initiation, A06515 to Exon-3 and A06516 to translation terminal). The total RNAs from the cells were extracted and the VEGF expression were examined with RT-PCR. The relative concentrations of VEGF transcripts in SMMC7721 cells from different groups were determined using GAPDH (glyceraldehyde-3-phosphate dehydrogenase) cDNA as internal standard. Results In response to the hypoxic challenge, SMMC7721 cells upregulated VEGF mRNA; Comparative to the control (no oligonucletides), A06513, A06514, A06515, and A06516 had obvious sequence-specific inhibitory effect on VEGF gene expression, with the ratio of VEGF over GAPDH of 0.49 ± 0.08, 0.71 ± 0.12, 0.72 ±0.11 and 0.86 ± 0.12, respectively (F = 12.21, P 0.05). A06513 showed the strongest inhibitory effect (P 0.01). Conclusion The antisense oligonucleotides complementary to VEGF cap structure, may become a potential alternative for antisense gene therapy of HCC.