Interestingly, the PD-L1 CCR could improve the cytotoxic activity of dual-targeted CAR-T cells against HER2+PD-L1+ tumor cells compared to that of single-targeted HER2 CAR-T cells which was attenuated in the presence of PD-L1 on HER2+ tumor cells (Fig. 5a-b), indicating that the PD-L1 CCR could partially antagonize PD-L1 mediated inhibition. The gene discussed is ERBB2; the disease is neoplasm.