Zhang et al. [264] found that PSG-1 had no anti-tumor activity in vitro, but was effective in activating peritoneal macrophages in CT26 tumor-bearing mice, enhancing the phagocytic capacity of macrophages and promoting the production of nitric oxide (NO), TNF-α and IL-1β in mice to enhance immune function. The gene discussed is PSG1; the disease is neoplasm.