Induction of prostaglandin E2 synthesis and microsomal prostaglandin E synthase–1 expression in murine microglia by glioma-derived soluble factors

Object Microglia are one of the members of monocyte/macrophage lineage in the central nervous system (CNS) and exist as ramified microglia in a normal resting state, but they are activated by various stimuli, such as tumors. Activated microglia induce immune responses in the CNS, but the precise functions of microglia in glioma microenvironments are not clear. It has been reported that glioma cells produce prostaglandin (PG)E2, which promotes the growth of tumor cells and possesses immunosuppressive activity. The authors previously reported that PGE2 production by peritoneal macrophages was enhanced by glioma-derived soluble factors, which induce an immunosuppressive state. In this study, they investigated PGE2 production by microglia treated with glioma cells and assessed the role of microglia in glioma microenvironments in the mouse. Methods Microglia and peritoneal macrophages were cultured in vitro with or without lipopolysaccharide, and tumor necrosis factor (TNF) and PGE2 in the culture supernatant ...