PTGS2 and prostate cancer: Aside from IL-18, in cancer patients and experimental tumor models, raised levels of IL-1β are also associated with a worse prognosis, carcinogenesis, and cancer invasion.295,296 For instance, IL-1β mediates the proliferation and invasion of colon epithelial cancer cells through the stromal cyclooxygenase-2 (COX-2) signaling pathway.297 In prostate cancer, IL-1β promotes cancer cells proliferation and metastasis by activating MAPK-mediated IL-8 production.298 By maintaining a microenvironment for cancer stem cells and promoting angiogenesis, IL-1β contributes to tumor growth and progression.