The so-called cell therapy is a method to produce cytokines that regulate cell functions by immune cells and related cells, and kill cancer cells directly or indirectly through cytokines to cause tumor regression and achieve therapeutic purposes. Cell therapy includes five major types of cytokines such as interferon, interleukin, tumor necrosis factor, colony-stimulating factor and transforming growth factor, etc. The mechanism of anti-tumor action of cell therapy is mainly direct killing and indirect killing. In the direct killing effect, some cytokines, such as interleukin-2, alpha-interferon and tumor necrosis factor, can play a direct role in killing cancer cells. In indirect killing effect, cytokines activate immune cells through mutual regulation, and promote the secretion of anti-cancer cytokines by anti-cancer immune cells, which can achieve the purpose of anti-tumor.