PDCD1 and neoplasm: To evaluate the effect of MDZ on tumour growth and PD-1 mAb therapeutic efficacy in of HCC in vivo, we subcutaneously injected murine Hepa1-6 cells into the C57BL/6 mice in the PBS, MDZ, α-PD-1, and α-PD-1 + MDZ groups and then injected the mice with PD-1 mAb to assess the antitumor effects.