Moreover, tumor cells also directly hamper the TAMs phagocytosis through immune checkpoints, such as CD47/signal regulatory protein-α (SIRPα), CD24/sialic acid binding Ig-like lectin 10 (SIGLEC10), major histocompatibility complex class I molecules (MHC-I)/leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1), and PD-1 ligand 1 (PD-L1)/programmed cell death protein-1 (PD-1) axis 3. This evidence concerns the gene PDCD1 and neoplasm.