The function of M2 macrophages in promoting tumor development depends on the proinflammatory cytokines, such as TNF-α, IL-6, and IL-11, which can activate the nuclear factor–κB (NF-κB) and signal transduction and activator of transcription 3 (STAT3) pathway in cancer cells (10, 12, 13, 18, 25). This evidence concerns the gene TNF and cancer.