OBJECTIVE: To explore the association between expression of ADAM17 and cetuximad resistance in human colorectal cancer SW480 cells. METHODS: The expression of ADAM17 was detected using Western blotting in different human colorectal cancer cell lines, and the cells highly expressing ADAM17 were selected as the target cells. SW480 cells were transfected with ADAM17-siRNA 1 and ADAM17-siRNA 2 and the changes in the expression of ADAM17 protein were detected using Western blotting. SW480 cells were exposed to cetuximad for 24 h and the cell apoptosis was analyzed using flow cytometry. Transwell assay was used to examine the migration ability of SW480 cells with different expression levels of ADAM17; Western blotting was used to analyze the changes in the expressions of AKT signaling pathway-related proteins in the treated cells. RESULTS: The baseline expressions of ADAM17 were significantly higher in SW480 cells than in the other human colorectal cancer cell lines tested ( < 0.05). Both ADAM17-siRNA 1 and 2 effectively reduced the expression of ADAM17 protein in SW480 cells. Knockdown of ADAM17 with siRNA 1 significantly increased the sensitivity of SW480 cells to tocetuximad ( < 0.05), obviously inhibited the cell proliferation, migration and invasion, and significantly reduced the expressions of p-EGFR and p-AKT in the cells ( < 0.001). CONCLUSIONS ADAM17 knockdown obviously inhibits EGFR-AKT signaling pathway and increases the sensitivity of SW480 cells to tocetuximad.
ADAM17 Protein ; genetics ; metabolism ; Antineoplastic Agents, Immunological ; pharmacology ; Apoptosis ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cetuximab ; pharmacology ; Colorectal Neoplasms ; drug therapy ; genetics ; metabolism ; pathology ; Drug Resistance, Neoplasm ; genetics ; ErbB Receptors ; metabolism ; Gene Knockdown Techniques ; Humans ; Neoplasm Invasiveness ; Oncogene Protein v-akt ; metabolism ; RNA, Small Interfering ; Signal Transduction ; Transfection ; methods

[Abstract] Objective: To screen candidate epitopes of breast cancer HLA-A2 restrictive neoantigen and to identify high frequency mutation sites in breast cancer neoantigen by using bioinformatics method. Methods: NCBI and GDC databases were used to search missense mutation sites formed by single nucleotide mutation in breast cancer among reported literatures and sequencing data. The new antigen epitopes were predicted by HLA-A2 antigen epitope prediction website BIMAS, SYFPEITHI and artificial neural networkbased NetMHC4.0, and the epitopes with TAP binding power less than Intermediate were eliminated. The candidate epitopes were prioritized by mutation frequency and prediction results. Results: A total of 17 high-frequency mutation genes, including BTLA, ERBB2 and NBPF12 etc, were screened by the above-mentioned methods, and a total of 26 neoantigen epitopes were identified. The binding power of epitopes predicted using BIMAS and SYFPEITHI showed great difference (P<0.05), epitopes in high priority as GSTP1 (A114V , mutation frequency of 5.94%) and BRCA2 (N991H, mutation frequency of 5.40%) etc, were expected to be candidate neo-antigen epitopes; however, their mutation frequency was relatively too low to achieve“universal use” . The possibility of these epitopes used as general breast cancer neo-antigen epitopes is less likely. Conclusion: The common mutation frequency of breast cancer is lower than that of other tumors; it ’s difficult to find“universal”new antigen epitopes of breast cancer; the individualized neoantigen vaccine may be of more promise, which needs further research.