CD274 and neoplasm: Since TAMs express PD1 to maintain an immunosuppressive M2 phenotype by PD1/PD-L1 signaling from tumor cells, and blockade of PD1/PD-L1 signaling by anti-PD1 Abs activates and re-polarizes TAMs toward an immunoreactive M1 phenotype, TAMs could represent a useful target for anti-PD1 Abs.