Anti-Inflammatory Mechanisms of Medroxyprogesterone Acetate (MPA) in Endometriosis

Summary: The proposed experiments will allow the fellowship applicant to characterize the pathways leading to TNF-alpha repression in endometriosis cell culture models, which should be applicable to future clinical trials of small molecule inhibitors. Introduction: Endometriosis, which affects 10% of all women in reproductive age is defined through the presence of endometrium outside the uterus. Endometriosis, a multifactorial disease, is influenced by genetic, hormonal, environmental and immuological factors. Despite multiple proposals, the etiology of the disease remains an enigma. The implantation hypothesis is the most widely accepted, supported by observations that retrograde menstruation and intraperitoneal spillage of viable endometrial cells occur frequently in cycling women. Considerable evidence supports a role for TNF-alpha in several aspects of endometriosis including propagation, angiogenesis and pain mediation. In a critical meta-analysis medroxyprogesterone acetate (MPA) was shown to afford a significant improvement in pelvic pain in 40-60% of subjets. Data from an in vitro model of endometriosis indicate that MPA has direct anti-inflammatory activity inhibiting the transcriptional activation of RANTES in primary stromal cell cultures. Aim of the Study: The aim of our study is to characterize the expression of TNF-alpha in primary endometrial and endometriotic cell cultures. Furthermore, the role of MPA and the progesterone receptor isoforms A and B in the regulation of TNF- alpha gene expression in a human endometriotic cell culture model will be explored. We will also investigate the mechanism of TNF-alpha gene repression, attempting to identify collaborating co-repressor proteins. Material and Methods: The techniques of endometriotic cell culture, RT-PCR, ELISA, immunoblotting, and differential gene transfection will be used to accomplish these aims.