RNAi-induced K-Ras Gene Silencing Suppresses Growth of EC9706 Cells and Enhances Chemotherapy Sensitivity of Esophageal Cancer

  • Wang, Xin-Jie (Department of Integrated Traditional Chinese and Western Medicine, The First Affiliated Hospital of Zhengzhou University) ;
  • Zheng, Yu-Ling (Department of Oncology, The First Affiliated Hospital of Zhengzhou University) ;
  • Fan, Qing-Xia (Department of Oncology, The First Affiliated Hospital of Zhengzhou University) ;
  • Zhang, Xu-Dong (Department of Oncology, The First Affiliated Hospital of Zhengzhou University)
  • Published : 2012.12.31


To analyze the growth, proliferation, apoptosis, invasiveness and chemotherapy sensitivity of EC9706 cells after K-Ras gene silencing, an expression carrier pSilencer-siK-Ras was constructed, and the EC9706 cell line was transfected using a liposome technique. Six groups were established: Control, siRNA NC (transfected with empty vector pSilencer2.1); Ras siRNA (transfected with pSilencer-siK-Ras2); Paclitaxel; Paclitaxel + siRNA NC; and Ras siRNA + Paclitaxel. After the treatment, RT-PCR, Western blotting, MTT assay, flow cytometry and the Transwell technique were used to assess expression of K-Ras mRNA and protein in EC9706 cells, as well as cell growth, proliferation, apoptosis and invasiveness. The effect of Paclitaxel chemotherapy was also tested. pSilencer-siK-Ras2 effectively down-regulated expression of K-Ras mRNA and protein in EC9706 cells, growth being significantly inhibited. Flow cytometry indicated obvious apoptosis of cells in the experimental group, with arrest in the G1 phase; cell migration ability was also reduced. After pSilencer-siK-Ras2 transfection or the addition of Paclitaxel, EC9706 cells were suppressed to different extents; the suppressive effect was strengthened by combined treatment. The results suggested that RNAi-induced K-Ras gene silencing could enhance chemotherapy sensitivity of esophageal cancer.



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