NOS2 and neoplasm: In particular, recent evidence seems to indicate that NO may act as an addition local immune checkpoint inhibitor, favoring immune evasion of the tumor, by modulation of the acquisition of stem cell-like capacities, the metabolic reprogramming of tumor-infiltrating immune cells, and the induction of myeloid-derived suppressor cells that deplete arginine, via the iNOS pathway, and consequently inhibit T cell function (96, 97).