M1 macrophages, which are stimulated by interferon (IFN)-γ (produced by T-helper 1 cells) and bacterial lipopolysaccharide, are generally considered to have pro-inflammatory and anti-tumor effects and express inflammatory factors including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. The gene discussed is IFNG; the disease is neoplasm.