Extracellular matrix remodelling in the endometrium and its possible relevance to the pathogenesis of endometriosis

Essential features of endometrial physiology involve the extracellular matr ix (ECM), In the pathogenesis of endometriosis, interactions of endometrios is cells,vith ECM can be postulated. Two systems of secreted proteases in t he endometrium, the plasmin(ogen) activator/inhibitor and the matrix metall oproteinases and their inhibitors were examined in cell cultures of uterine endometrial cells from women with and without endometriosis, Soluble uroki nase receptor secretion is increased, and mRNA transcription of tissue inhi bitor of metalloproteinases-2 (TIMP-2) is upregulated by progestin in endom etriosis, These findings are compatible with an altered ECM turnover in the endometrium of these patients that may explain a higher invasive potential of retrogradely menstruated endometrial fragments.