As TAMs are the primary source of IL-10 in tumors and IL-10 can promote the expression of PD-L1 on monocytes, PD-L1+ monocytes can effectively inhibit tumor-specific T-cell immunity via the infiltration of Tregs and dysfunction of CD8 T-cells (Zhang et al., 2020; Figure 1). This evidence concerns the gene CD274 and neoplasm.