Abstract:To investigate the proliferation and invasion of A549 cell by down-regulating KSP and VEGF gene.Designing and screening the siRNA of targeting VEGF and KSP promoter, transfected into A549 cells with transfetion reagent. According to the difference of transfection mixture the cells were divided into five groups.Western Blotting was used to detect the expression of VEGF and KSP. MTT assay was used to detect the cell proliferation, qPCR was used to measure the expression of VEGF and KSP, the MTT results indicated that the proliferation of the cells was significantly decreased; The results of qPCR showed that the siRNA obviously decreased the expression of VEGF and KSP gene;. The Western Blotting showed that the expression of VEGF and KSP were significantly reduced; The proliferation of the co-transfected cell were inhibited more than the single group transfected cell. These results indicate that co-regulation of VEGF and KSP gene expression more effectively inhibit A549 cell proliferation, better than only regulating VEGF or KSP gene expression.