Tumor necrosis factor α (TNF alpha) is an effective pro-inflammatory cytokine, which can kill and inhibit tumor cells. It is mainly produced by activated macrophages and can also be secreted by other types of cells, such as CD4+ lymphocytes, NK cells, neutrophils, mast cells, eosinophils and neuronal tissues. The members of TNF alpha family exert their cellular effect through two distinct surface receptors of the TNF receptor family, TNFR1and TNFR2. The pleiotropic biological effects of TNF can be attributed to its ability to simultaneously activate multiple signaling pathways in cells. TNF-induced NF-κB activation promotes the growth, invasion and metastasis of cancer cells.