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*

OBJECTIVETo investigate the impact of human peritoneal mesothelial cells (HPMC) on angiogenesis factor expression and secretion of ovarian carcinoma cell line SKOV3.

METHODSThe conditioned medium with HPMC was tested by ELISA for tumor necrosis factor-alpha (TNF-alpha) and interleukin 10 (IL-1beta). Millicell was used to co-culture HPMC and ovarian carcinoma cell line SKOV3 in the presence or absence of neutralizing antibody against TNF-alpha or IL-1beta. RT-PCR was used to detect vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) gene expression in SKOV3 cells. VEGF and bFGF protein levels in the SKOV3 conditioned medium were assessed by ELISA.

RESULTSConditioned medium with HPMC contained both TNF-alpha and IL-1beta. SKOV3 co-cultured with HPMC expressed higher levels of VEGF and bFGF mRNA and secreted at increased levels of both VEGF and bFGF, in comparison with those in SKOV3 cells cultured alone (P < 0.01). Addition of neutralizing antibody against TNF-alpha or IL-1beta during co-cultures resulted in decrease in mRNA expression and secretion of VEGF and bFGF in SKOV3 cells. When both antibodies were administered during co-culture, additive decrease was observed.

CONCLUSIONHPMC can act in a paracrine fashion to stimulate ovarian tumor cells to produce and secret at increased levels of VEGF and bFGF through TNF-alpha and IL-1beta, and contribute to angiogenesis and peritoneal metastasis of ovarian cancer.

Antibodies ; pharmacology ; Cell Line, Tumor ; Cells, Cultured ; Coculture Techniques ; Culture Media, Conditioned ; metabolism ; Cystadenocarcinoma, Serous ; genetics ; metabolism ; pathology ; Enzyme-Linked Immunosorbent Assay ; Epithelial Cells ; secretion ; Female ; Fibroblast Growth Factor 2 ; genetics ; secretion ; Gene Expression ; drug effects ; Humans ; Interleukin-1beta ; immunology ; secretion ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; Peritoneal Cavity ; cytology ; RNA, Messenger ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Necrosis Factor-alpha ; immunology ; secretion ; Vascular Endothelial Growth Factor A ; genetics ; secretion