According to the PD-1/PD-L1 recognition mechanism, many PD-1 monoclonal antibodies, such as BMS-936558, have been approved by the FDA for use in clinic and have achieved great efficacy in the treatment of certain advanced malignant tumors, although PD-1 inhibitors have a curative effect only on a small proportion of cancer patients (69). This evidence concerns the gene CD274 and cancer.