[TNF-alpha].

TNF-alpha, a cytokine with tumor necrosis activity produced by many types of cells including macrophages, was recently recognized as an important host defense factor that affects not only malignant cells, but many kinds of normal cells. Clinical applications of TNF-alpha are now limited, but local injection or local production of TNF-alpha should be given closer consideration in antitumor trials. Here we described the TNF receptor family and TNF-alpha-driven inflammation, and also discussed the physiological roles of TNF-alpha.