Zhang et al. reported that compared with CAR-T cells targeting region I, CAR-T cells targeting region III had the following effects: (1) expressed higher levels of lethality markers after activation; (2) produced higher levels of cytokines and had stronger tumor killing effects when cocultured with multiple MSLN-expressing cancer cells; and (3) exhibited stronger antitumor responses against gastric cancer and inhibited the growth of large ovarian tumors. The gene discussed is MSLN; the disease is cancer.