NOS2 and neoplasm: M1-type macrophages, as a potent anti-tumor immune cell, express high levels of markers (human: CD68, CD80, CD86, MHC-II, IL-1R, IL-12, TLR-2, TLR-4 and inducible nitric oxide synthase 2 (iNOS2; mice: CD68, CD80, CD86, MHC-II, IL-12, IL-23), and secrete a variety of inflammatory cytokines, such as interleukin-1β (IL-1β), IL-6, and IL-12, to exert anti-inflammatory and tumor-suppressive effects (7).