PDCD1 and neoplasm: Compared with those in the anti-MSLN CAR-T-cell+PD-1 mAb and anti-MSLN CAR-T control groups, PD-1-disrupted anti-MSLN CAR-T cells could better inhibit the growth of tumor cells and had a stronger ability to prevent recurrence, which may be related to the degree of T-cell exhaustion [111].