RESUMEN
@#[Abstract] Objective: To investigate the effect of 18H12, a functional monoclonal antibody that can target gastric cancer stem cells, on the self-renewal and invasion ability of gastric cancer cells. Methods: The gastric cancer cell line PAMC-82 was used as cell model, the expression of ENO1 (enolase-1) on the membrane surface of its parental cells and enriched stem cells by sphere culture was detected by Flow cytometry. Flow cytometry was used to separate ENO1+ cells and ENO1- cells to detect their self-renewal ability and invasion ability. With the commercial ENO1 antigen and antibody as the samples, CoIP (co-immunoprecipitation) was used to verify whether 18H12 antibody targeting ENO1 could able to accurately recognize ENO1. After being treated with 18H12 for 12 h, 24 h and 48 h, the selfrenewal and invasion ability of PAMC-82 cells were detected by methylcellulose pelletization experiment and Transwell chamber assay, respectively. Results: Flow cytometry showed that the expression of ENO1 on the membrane surface of PAMC-82 sphere cells was significantly higher than that of its parental cells (P<0.01), so ENO1 could be a potential target for targeting gastric cancer stem cells. The self-renewal ability and invasion ability of the sorted ENO1+ cells were significantly stronger than those of the ENO1- cells and the parental cells (P<0.05 or P<0.01). 18H12 antibody could accurately recognize ENO1, which was consistent with the commercial antibody recognition band. 18H12 could significantly inhibit self-renewal ability and invasion ability of PAMC-82 cells (P<0.01). Conclusion: Monoclonal antibody 18H12 can significantly inhibit the self-renewal and invasion of gastric cancer stem cells and is expected to be a candidate antibody drug targeting gastric cancer stem cells.