ENDOMETRIOSIS The role of prostaglandin E2 in endometriosis

Endometriosis is a leading cause of infertility in women of reproductive age. It involves the occurrence of endometrial tissue outside the uterine endometrium, mainly in the peritoneal cavity. Prostaglandin E2 is up regulated in the peritoneal cavity in endometriosis and is produced by macrophages and ectopic endometrial cells. This prostaglandin is involved in the pathophysiology of the disease and elicits cell signals via four receptor types. Prostaglandin E2 increases estrogen synthesis by up regulating steroidogenic acute regulatory protein (StAR) and aromatase. It inhibits apoptosis and up regulates fibroblast growth factor-9 (FGF-9) promoting cell proliferation. Prostaglandin E2 affects leukocyte populations and promotes angiogenesis through its effect on estrogen and up regulation of vascular endothelial growth factor (VEGF). Dienogest is a synthetic