The association of an anti-PD-1/PD-L1 with an anti-HER2 antibody can enhance its effect by reducing the immune escape of tumor cells, facilitating the elimination of cancer cells by trastuzumab indirectly, promoting dendritic cell trafficking and increasing the effect and the expansion of peripheral memory T cells [23,62,88,95,96,97,98]. The gene discussed is CD274; the disease is cancer.