Abstract Prostaglandin E2 (PGE2) is the most abundant eicosanoid and a very potent lipid mediator. PGE2 is produced predominantly from arachidonic acid by its tightly regulated cyclooxygenases (COX) and prostaglandin E synthases (PGES). Secreted PGE2 acts in an autocrine or paracrine manner through its four cognate G protein coupled receptors EP1 to EP4. Under physiological conditions, PGE2 is key in many biological functions, such as regulation of immune responses, blood pressure, gastrointestinal integrity, and fertility. Deregulated PGE2 synthesis or degradation is associated with severe pathological conditions like chronic inflammation, Alzheimer's disease, or tumorigenesis. Therefore, pharmacological inhibition of COX enzymes and PGE2 receptor antagonism is of great therapeutic interest.