Objective     To construct and identify the RNAi eukaryotic vector of Skp2 gene and to observe its interfering effect on the growth of SPC-A-1 lung cancer cells.     Methods    The specific shRNA sequence was designed and synthesized according to the Skp2 cDNA sequence in GenBank. The sequence was cloned into plasmid pGenesil-1. Then recombinant vector was transfected into SPC-A-1 lung cancer cells by Lipofectamine 2000.The expressions of Skp2 mRNA were analyzed by RT-PCR and the levels of Skp2 protein were detected by Western blot. The cell growth suppression was analyzed by MTT assay. Distribution of cell cycle was assessed by flow cytometry． 

   Results    The sequence of template and specific siRNA was correct by sequence analysis. Obvious decrease was observed in the levels of Skp2 mRNA and Skp2 protein after Skp2 shRNA transfection(P0.05).The subcloned recombinant plasmid expressing Skp2 shRNA effectively inhibited lung cancer cell growth

while empty plasmid had no such specific effect(P0.05)

induced cell cycle arrest in G

0

/G

1

phase with a significant decrease of cells in S phase(P0.05).     Conclusion    The successful construction of Skp2 shRNA vector

which could effectively abate the expression of Skp2 and inhibit the growth of SPC-A-1 lung cancer cells

laid the foundation for further study on the function of Skp2 gene and gene therapy of lung cancer.