It has been reported in the literature that the infiltration of M2-TAMs is significantly associated with poor prognosis, progression, and other adverse clinical outcomes in a wide range of cancers (26, 27); however, M2-TAMs can also inhibit the immunotherapeutic effect by suppressing T-cell activity and enhancing the PD-L1 expression in the TME during anti-PD-1/PD-L1 immunotherapy (28–30). This evidence concerns the gene CD274 and cancer.