Three-dimensional culture of endometrial cells: an in vitro model of endometriosis

Endometriosis is the presence of endometrial tissue outside of the uterine cavity and is the most common gynecologic disorder in women of reproductive age. Although the quality of life for women with endometriosis is severely compromised, very little is known about the pathophysiology of endometriosis and current therapeutic strategies provide temporary symptomatic relief but not a cure. Endometriosis remains poorly understood primarily because of an inability to identify patients with early stage disease. Animal models have been developed to study early endometriosis but all have some problems that limit their usefulness in determination of the pathophysiology of endometriosis as it occurs in the human. We have preliminary evidence that in the presence of a three-dimensional fibrin matrix, human endometrial glands, stroma, and neovascularization can develop in vitro, mimicking the earliest stages of endometriosis. We believe this model system reflects the situation in the peritoneal cavity of women following retrograde menstruation when endometrial fragments, fibrin, leucocytes and cytokines are trapped in pockets in the dependent parts of the pelvis, allowing endometrial cell proliferation, invasion and angiogenesis to occur. In the present review article, we will further discuss this in vitro model of early endometriosis and discuss possible anti-angiogenic drugs that are already commercially available in an attempt to find an effective and specific treatment for endometriosis.