Abnormal Expression Of WIF-1 In Hepatocellular Carcinoma Cells And Its Regulation On Tumor Invasion And Metastasis Factors TIMP -3 And Caveolin -1

Objective: in primary hepatocytes or intrahepatic vessel element,90 % of malignant tumors are hepatocellular carcinoma(HCC),the fifth most common solid tumor in the world.It has a poor prognosis and is difficult to prevent and treat clinically.Most HCC patients who underwent hepatectomy relapsed after surgery,leading to a higher mortality rate.The main reason is the invasion and metastasis of liver cancer.Therefore,in-depth study of the invasion and metastasis mechanism of hepatocellular carcinoma is of great significance to improve the effective prevention and treatment of hepatocellular carcinoma and improve the therapeutic effect of hepatocellular carcinoma.Wnt gene was discovered by nuse in 1982 in breast cancer mice.Wnt signaling pathway is a highly reserved signaling pathway in multicellular eukaryotes that regulates many biological processes.Wnt inhibitor-1(WIF-1)is a secretory antagonist of Wnt signaling pathway.the expression of WIF-1 protein and mRNA in liver cancer tissues is lower than that in adjacent tissues,and the overall survival rate is related to the lower expression of WIF-1.The invasion and metastasis of cervical cancer cells and prostate cancer cells can be significantly inhibited by up-regulating the expression of WIF1.We hypothesized that WIF-1 might affect the invasion and metastasis of HCC cells through related signaling pathways.The expression of caveolin-1 is closely related to the occurrence and development of hepatocellular carcinoma.The expression of WIF-1 in hepatocellular carcinoma cell line was detected.In addition,the effects of eukaryotic expression vector PC DNA 3.1-WIF on the invasion and metastasis of hepatocellular carcinoma cell lines and the effects of WIF-1 overexpression on TIMP-3 and caveolin-1 expression were investigated and the possible mechanisms were discussed.Methods:1.The expression of WIF-1 in HepG2,Hep3 B,Huh7,PLC/PRF/5,SMMC-7721,MHCC97 were detected by RT-PCR and western blot.2.The eukaryotic expression vector PC DNA 3.1-WIF-1 and blank plasmid PC DNA 3.1 were transfected into hepatocellular carcinoma cell line using liposome 2000.3.The effects of WIF-1 on the invasiveness of hepatoma cells were examined by transwell transmembrane assay.4.Western blot was used to detect the effects of WIF-1 on TIMP-3(matrix metalloproteinase tissue inhibitor 3)and caveolin-1 expression in hepatocellular carcinoma cells and ?-catenin expression.Results:1.The expression of WIF-1 in hepatocellular carcinoma cell line was lower than that in normal hepatocyte line(P<0.01).Furthermore,WIF-1 was not expressed substantially in human highly metastatic cell line MHCC97,but moderately expressed in HepG2 and SMMC-7721.2.The vector PCDNA 3.1-WIF-1 and blank plasmid PCDNA 3.1 transfected into hepatocellular carcinoma cell line,compared with the blank plasmid group,cell viability decreased significantly.3.The invasion ability of liver cancer cells with high expression of WIF-1 was significantly decreased.4.Both TIMP-3 and caveolin-1 mRNA and protein expression decreased in high expression WIF-1 hepatocellular carcinoma cells.5.Increased expression of WIF-1 may lead to down-regulation of ?-catenin protein expression in HepG 2 and SMMC-7721 cells.Conclusion:1.WIF-1 was down-regulated or not expressed in HCC cell lines compared with normal hepatocytes.2.Up-regulation of WIF-1 expression can significantly inhibit the invasion and metastasis of HepG 2 and SMMC-7721 cells.This is related to up-regulation of TIMP-3 expression and down-regulation of caveolin-1 expression,and may be achieved through Wnt / ?-catenin signaling pathway.