Study shows that The combination of PD-1 blockade with IFN α significantly improved the effect of PD-1 antibody monotherapy, prolonged the survival period of mice, enhanced the secretion and activation of T cells in liver cancer mouse models, restored or even enhanced the cytotoxic effect of CD8+T cells, and had a synergistic anti-tumor effect (157). The gene discussed is PDCD1; the disease is liver cancer.