Aim: To construct antisense VEGF(165) eukaryotic expression vector PCDNA(3)-as-VEGF(165) and to study its expression and effect on the proliferation of hepatocarcinoma SMMC-7721 cells.
Methods: VEGF(165) cDNA was inserted into polylinker sites of eukaryotic expression vector PCDNA(3) to construct PCDNA(3)-as-VEGF(165). Then the vector was transferred into human hepatocarcinoma cell strain SMMC-7721 with cation lipofectamine 2000 mediated methods to evaluate the expression of VEGF protein and the inhibitory effect on the proliferation of hepatocarcinoma SMMC-7721 cells.
Results: The detection indicated the presence of VEGF cDNA in normally cultured SMMC-7721 cells by PCR. VEGF mRNA expression was notably decreased in SMMC-7721 cells by RT-PCR after PCDNA(3)-as-VEGF(165) transfection. The expression of VEGF protein was dramatically inhibited (142.01+/-7.95 vs 1 625.52+/-64.46 pg/ml(-1), P<0.01) 2 days after transfection, which correlated with the dose of PCDNA(3)-as-VEGF(165)5 gene. VEGF protein was most expressed in PCDNA(3) transferred SMMC-7721 cells but few in PCDNA(3)-as-VEGF(165) transferred cells by immunohistochemical staining. The apoptotic rate of hepatocarcinoma SMMC-7721 cells was significantly promoted (17.98+/-0.86% vs 4.86+/-0.27%, P<0.01) and the survival rate was notably decreased (80.99+/-3.20% vs 93.52+/-3.93%, P<0.05) due to antisense VEGF(165) by flow cytometry (FCM). The transfection of antisense VEGF(165) gene resulted in the inhibitory effect on the proliferation of hepatocarcinoma cells by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and the death of all hepatocarcinoma cells on day 6 after transfection.
Conclusion: It is confirmed that antisense VEGF(165) can inhibit the expression of VEGF protein, interfere with the proliferation and induce the apoptosis of hepatocarcinoma cells in our study. Antisense VEGF(165) gene therapy may play an important role in the treatment of human hepatocarcinoma.