Study Of EPCAM Gene Expression Downregulation By SiRNA On The Proliferation And Invasion Of Colon Cancer Cell Line HCT116

Objective:Colon cancer in China is one of the most common gastrointestinal malignancy, in our country, because those who died of colon cancer, male cancer deaths ranked fifth, women ranked No.6, from the epidemiological point of view, the colon cancer incidence and social environment, lifestyle (especially diet, lack of physical activity), genetic factors. Age, history of colorectal polyps, ulcerative colitis risk factors and history of cholecystectomy is colon cancer. Overall, however, the cause of colon cancer is not yet clear. This study was designed to investigate the effects on HCT116 colon cancer cell proliferation and invasion of siRNA after EPCAM gene expression, thereby EPCAM explore the relationship between genes and the development of colon cancer.Methods:Three EPCAM siRNA sequences and one negative control siRNA sequence were designed and synthesized, and then transfected into HCT116 cells. The most effective EPCAM-siRNA was screened by real time PCR and Western blotting. After the most powerful EPCAM-siRNA were transfected into colon cancer cell line HCT116, cell proliferation was analyzed by MTT assay, and invasive ability of colon cancer cell HCT116 was assayed by Transwell.Results:All of the three EPCAM-siRNA could effectively restrain EPCAM gene expression. RT-PCR results showed that the mRNA expression of EPCAM gene in colon cancer cell transfected with EPCAM-siRNAs were 0.18?0.02?0.43±0.03?0.68±0.02 respectively, which was significantly lower than that in blank and negative control groups (0.98±0.02,0.96±0.03 P=0.008). Western-blot revealed that the relative expression of EPCAM protein in colon cancer cell HCT116 transfected with EPCAM-siRNAs were 0.22±0.03?0.43±0.02?0.71±0.03, which was significantly lower than that in blank and negative control groups (0.93±0.02,0.89±0.02 P=0.005). After transfected with EPCAM-siRNAl, the proliferation ability of cells were significantly inhibited and the inhibition rate was 41% after 48h, as compared with the control group s, the difference was significant (P=0.013). Transwell showed that the number of transfencted group cell which invaded to the membrane was 19, which was significantly lower than that in blank and negative control groups (45,41, P=0.03).Conclusion:EPCAM siRNA can effectively inhibit the expression of EPCAM gene in colon cancer line HCT116, and can significantly depress the proliferation and invasion of colon cancer line HCT116.