The Effects Of Recombinant Ad-delivered VEGF Ribozyme On Cell Growth And VEGF Expression Of Lung Adenocarcinoma Cell Line A549

Objective: To observe the effects of recombinant Ad-delivered VEGF hairpin ribozyme(VEGF/Rz) on cell growth and VEGF expression of lung adenocarcinoma cell line A549 in vitro.Methods:The recombinant adenovirus carring artificial VEGF hairpin ribozyme and green fluorecent protein(GFP) (Ad- VEGF/Rz- GFP) and the blank adeno virus containing GFP (Ad-GFP)were proliferated respectively in human embryonal kidney QBI-293A(QBI-HEK-293A)cell line. Then the A549 cell was infected by Ad-VEGF/Rz- GFP and Ad-GFP respectively at 100 motiplicies of infection(MOI). The expression of VEGF/Rz in A549 cell was tested by RT- PCR. ELISA was used to measure the concentration of VEGF in supernatant of A549 cell. The inhibition rate of A549 cell growth was detected by MTT.Cytopathic Effect(CPE)of the A549 cell was observed through FM. The A549 cell apoptic rate was examined by FCM.Results: Both Ad-VEGF/Rz-GFP and Ad-GFP multiplied by QBI-HEK-293A could infect A549 cell line. RT-PCR showed that VEGF hairpin ribozyme could be delivered into A549 cell line. ELISA revealed the level of VEGF concentration in supernant of A549 infeced by Ad-VEGF/Rz-GFP decreased signicantly compared with that of Ad-GFP and A549 cell controls. MTT showed Ad-VEGF/Rz-GFP at different MOI could inhibit A549 cell growth in a dose-and-time dependent manner (P<0.05),while the Ad-GFP group at 100MOI exerted slight inhibitive effect on A549 cell growth . Cytopathic Effect(CPE)of A549 infected by Ad-VEGF/Rz-GFP was more significant than that of Ad-GFP controls . FCM revealed that Ad-VEGF/Rz-GFP group had a high cell apoptic rate compared with the Ad-GFP and blank cell groups.Conclusion:Ad-VEGF/Rz-GFP can successfully infect the lung adenocarcinoma cell line A549. VEGF/Rz can be expressed in A549 cell infected by Ad-VEGF/Rz-GFP. Ad-VEGF/Rz-GFP can significantly inhibit the cell growth in vitro.The study showed that Ad-VEGF/Rz-GFP can reduce the secretion of VEGF, inducing the cell apoposis of lung adenocarcinoma A549 cell in vitro.