The study aimed to construct the second and third generation chimeric antigen receptor T cells (CAR-T) targeting the c-mesenchymal-epithelial transition factor (c-Met) protein, and observe their killing effect on human serous ovarian cancer cell SKOV-3. The expression of MET gene in ovarian serous cystadenocarcinoma, the correlation between MET gene expression and the abundance of immune cell infiltration, and the effect of MET gene expression on the tissue function of ovarian serous cystadenocarcinoma were analyzed by bioinformatics. The expression of c-Met in ovarian cancer tissues and adjacent tissues was detected by immunohistochemical staining. The second and third generation c-Met CAR-T cells, namely c-Met CAR-T(2G/3G), were prepared by lentivirus infection, and the cell subsets and infection efficiency were detected by flow cytometry. Using CD19 CAR-T and activated T cells as control groups and A2780 cells with c-Met negative expression as Non target groups, the kill efficiency on SKOV-3 cells with c-Met positive expression, cytokine release and cell proliferation of c-Met CAR-T(2G/3G) were explored by lactate dehydrogenase (LDH) release, ELISA and CCK-8 respectively. The results showed that MET gene expression was significantly up-regulated in ovarian cancer tissues compared with normal tissues, which was consistent with the immunohistochemistry results. However, in all pathological stages, there was no obvious difference in MET expression and no correlation between MET gene expression and the race and age of ovarian cancer patients. The second generation and third generation c-Met CAR-T cells were successfully constructed. After lentivirus infection, the proportion of CD8⁺ T cells in c-Met CAR-T(2G) was upregulated, while there was no significant change in the cell subsets of c-Met CAR-T(3G). The LDH release experiment showed that the kill efficiency of c-Met CAR-T(2G/3G) on SKOV-3 increased with the increase of effect-target ratio. When the effect-target ratio was 20:1, the kill efficiency of c-Met CAR-T(2G) reached (42.02 ± 5.17)% (P < 0.05), and the kill efficiency of c-Met CAR-T(3G) reached (51.40 ± 2.71)% (P < 0.05). ELISA results showed that c-Met CAR-T released more cytokine compared to CD19 CAR-T and activated T cells (P < 0.05). Moreover, the cytokine release of c-Met CAR-T(3G) was higher than c-Met CAR-T(2G) (P < 0.01). The CCK-8 results showed that after 48 h, the cell number of c-Met CAR-T(2G) was higher than that of c-Met CAR-T(3G) (P < 0.01). In conclusion, both the second and third generation c-Met CAR-T can target and kill c-Met-positive SKOV-3 cells, with no significant difference. c-Met CAR-T(2G) has stronger proliferative ability, and c-Met CAR-T(3G) releases more cytokines.
Humans ; Female ; Ovarian Neoplasms/immunology* ; Proto-Oncogene Proteins c-met/metabolism* ; Receptors, Chimeric Antigen/immunology* ; Cell Line, Tumor ; Cystadenocarcinoma, Serous/immunology* ; T-Lymphocytes/immunology*

BACKGROUND/AIMS: The aim of this study was to investigate the immunohistochemical overexpression of c-erbB-2 and c-met proteins according to the histopathological parameters such as grade of dysplasia, histological type, depth of invasion, lymph node metastasis, and TNM stage in gastric adenoma and gastric adenocarcinoma. METHODS: Immunohistochemical staining using monoclonal c-erbB-2 and c-met antibodies was performed on paraffin embedded specimens in 43 adenomas and 44 adenocarcinomas. RESULTS: The expression rate of c-erbB-2 was higher in adenomas (91%) than adenocarcinomas (30%). The expression rate of c-met was higher in adenocarcinomas (77%) than adenomas (49%). In adenoma, the expression rate of c-met was higher in high grade dysplasia (94%) than in low grade dysplasia (22%). In adenocarcinoma, c-met expression was significantly related with lymph node metastasis. CONCLUSIONS: c-erbB-2 would be involved in the development of relatively early stage gastric carcinogenesis. c-erbB-2 is related with histologic type and c-met with lymph node metastasis in gastric carcinomas. Although meaning for the experession of these proteins in gastric carcinomas would be different, these proteins may play as important oncogenes in gastric carcinogenesis.
Adenocarcinoma/*metabolism/pathology ; Adenoma/*metabolism/pathology ; Aged ; Antibodies, Monoclonal ; Disease Progression ; Female ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Middle Aged ; Proto-Oncogene Proteins c-met/immunology/*metabolism ; Receptor, erbB-2/immunology/*metabolism ; Stomach Neoplasms/*metabolism/pathology ; Tumor Markers, Biological