TNF and neoplasm: M1 macrophages are stimulated by IFN-γ, LPS, TNF-α or GM-CSF, and inhibit tumor growth by producing pro-inflammatory cytokines such as: IL-1, -6, -8, -12, -23, TNF-α, small quantities of IL-10 as well as ROS (reactive oxygen species) and RNI (reactive nitrogen intermediates) [13].