BACKGROUND: It is widely recognized that the growth of solid tumor depends on angiogenesis. Vascular endothelia growth factor (VEGF) is an endothelial cell-specific mitogen that promotes angiogenesis in solid tumor. Inhibition of angiogenesis is considered a promising approach for cancer therapy, and treatments including administration of antisense drugs and RNA interference for the VEGF gene are geared to the suppression of  tumor angiogenesis.
METHODS: As a new approach for gene therapy of hepatocellular carcinoma (HCC）, four groups of antisense oligodeoxynucleotide (ASODN) (A-Cap, A-AUG, A-UGA and A-Exon-3) were used to block the expression of VEGF, then VEGF mRNA and protein were detected by RT-PCR and Western blot.
RESULTS:
After treatment with ASODN, the relative VEGF mRNA levels of  A-Cap, A-AUG, A-UGA, and A-Exon-3 were decreased significantly to (32±9)%, (63±1)%, (86±3)%, and (70±5)%, respectively（F=64.18, P<0.001）. The relative VEGF protein levels of A-Cap, A-AUG, A-UGA and A-Exon-3 were decreased significantly to (41±5)%, (59±3)%, (88±7)%, and (79±9)% respectively (F=60.64, P<0.001）.
CONCLUSIONS: Among the four ASODNs, the ASODN for Cap structure showed the strongest inhibitory effect and that for A-UGA, the least (P<0.05 ）. The inhibitory effect of ASODN on the expression of VEGF proteins was similar to that of  VEGF mRNA expression.