[Effect of inhabitation of VEGF expression with RNA interference on lung cancer therapy]

To observe the effect of inhabitation of VEGF expression by RNA interference on the therapy of lung cancer and to obtain a novel strategy of lung cancer therapy by RNA interference.

A segment of VEGF-siRNA was synthesized according to the code of siRNA design. The constructed pSilencer-3.1-VEGF vectors were stably transfected into A549 cell line. Then the expression of VEGF was detected in stable transfectant A549 cell line by TR-PCR and Western blot. Meanwhile, the growth of stable transfectant A549 cell line and the angiogenesis of endothelial cells were studied. The tumor volume was detected in stable transfectant A549 bearing mice.

The expression of VEGF in stable transfectant A549 cell line was obviously inhibited by pSilencer-3.1-VEGF-2. Although it did not inhibit the growth of A549, it decreased the angiogenesis of endothelial cells. In vivo, compared with control group, the tumor in the pSilencer-3.1-VEGF-2-A549 bearing mice(P<0.05)growth was obviously at a slow, and the survival obviously lengthened in the pSilencer-3.1-VEGF-2-A549 bearing mice(P<0.05).

A pSilencer-3.1-VEGF vector has been successfully constructed. pSilencer-3.1-VEGF-2 can silence the expression of VEGF in A549. It can inhibit the angiogenesis of endothelial cells in vitro and the tumor growth and lengthen the survival of the bearing mice in vivo.