Prostaglandin E2 pathway in colonic macrophage

The **prostaglandin E₂ (PGE₂) pathway in colonic macrophages** refers to the network involving cyclooxygenase enzymes—primarily COX‑2—and prostaglandin E synthases that convert arachidonic acid into PGE₂. This lipid mediator acts through four G protein-coupled receptors—EP1, EP2, EP3, and EP4—expressed on various cells including colonic tissue-resident macrophages[1][6]. In the colon, **macrophage-derived PGE₂** plays complex roles. It regulates local immune responses by modulating T cell activity and maintaining epithelial barrier integrity[4][5]. The balance between pro-inflammatory M1-like and anti-inflammatory M2-like phenotypes is influenced by this signaling axis[2]. Dysregulation promotes chronic inflammation—as seen in inflammatory bowel disease—and supports tumor growth by fostering an immunosuppressive microenvironment that enables colorectal cancer progression[3]. Therapeutically targeting this axis is under investigation for both inflammatory diseases like IBD—by shifting polarization toward anti-inflammatory states—and cancers such as CRC—by inhibiting protumoral functions or reprogramming tumor-associated macrophages toward antitumoral activity[1][3]. However, broad inhibition carries risks due to disruption of protective mucosal functions.

Other names

COX-2–PGE2 pathway in colonic macrophagesColonic macrophage prostaglandin E2 signalingPGE2-EP receptor axis in colon macrophages

- Inhibition of cyclooxygenase enzymes reduces PGE2 synthesis and downstream pro-inflammatory/pro-tumorigenic effects [1][5]. - Antagonism or modulation of EP receptors alters immune cell function and inflammation [4][5].