The Role Of Cathepsin B In The Proliferation And Invasion Of Esophageal Squamous Cell Carcinoma

Goals: To investigate the expression of cathepsin B in esophageal squmous cell carcinoma and its effect on the proliferation and invasion of EC9706 cells.Materials and methods:A total of 53 cases of esophageal squamous cell carcinoma specimens resected by cardiothoracic surgery in our hospital were collected,clinical data and information of the patients were recorded,and the expression of cathepsin B in cancer tissue,paracancer tissue and high-grade intraepithelial neoplasia of esophagus were detected by Western blotting,immunohistochemical,RT-PCR staining and other methods.To investigate the relationship between its expression level and clinicopathology in patients with esophageal squamous cell carcinoma.To investigate the effect of silencing cathepsin B gene in human esophageal cancer cell line EC9706 combined with clinical chemotherapy drugs paclitaxel and cisplatin on the proliferation and invasion ability of human esophageal cancer cell line EC9706.1.Interference group: silence cathepsin B;2.2.Drug group: paclitaxel + cisplatin;3.Interference + drug group: silencing cathepsin B+ paclitaxel + cisplatin;4.Negative control group: independent siRNA sequences were added;5.Blank control group: no treatment.Results:The results of Western blotting,immunohistochemical,RT-PCR staining showed that the expression of cathepsin B in esophageal squamous cell carcinoma was increased.The analysis of the patient's linchuan data showed that the positive expression of cathepsin B was significantly correlated with the differentiation degree of tumor tissue and lymph node metastasis(P<0.05).However,there was no significant correlation with gender,tumor infiltration depth,maximum diameter of the tumor,distant metastasis and clinical stage of the patient(P>0.05).The human esophageal cancer EC9706 cell line was successfully silenced and the protein expression of cathepsin B was down-regulated by Western blotting(P<0.05).Targeting cathepsin B expression,silent CCK8 test results: the cell proliferation carcinoma strain in silence cathepsin B after 24,36,48,72 h four corresponding period compared with the blank control group,negative control group showed proliferation to reduce the phenomenon,but only in 48 h and 72 h both differences compared to just have significant(P< 0.05),indicating that cathepsin B cell proliferation activity decline after gene silencing.The results of Transwell cell migration experiment showed that the number of cells passing through the compartment in the interference group,drug group and interference + drug group was significantly lower than that in the blank control group and the negative control group(P<0.01).There was no statistically significant difference between the three groups(P>0.05).There was no statistically significant difference between blank control group and negative control group.Conclusions:The results showed that the expression of cathepsin B in esophageal squamous cell carcinoma was up-regulated compared with that in paracancer tissue.And its expression level was gradually increased in "normal esophagus--high-grade intraepithelial neoplasia of esophagus--esophageal squamous cell carcinoma".After silencing the cathepsin B gene in human esophageal cancer cell EC9706,its ability to proliferate and invade in vitro was significantly inhibited.It is concluded that cathepsin B plays an important role in the proliferation and invasion of esophageal cancer.