Tenascin is differentially expressed in endometrium and endometriosis

Endometriosis is characterized by the presence of functional endometrial ti ssue outside the uterine cavity, most commonly on the ovary and peritoneum. The aetiology of endometriosis is not understood, although the adhesion of endometrial cells to the extracellular matrix (ECM) would be expected to p lay a central role in its pathogenesis. The expression of ECM molecules in endometrium and in endometriosis has been investigated using immunohistoche mistry and western blotting techniques. The ECM components collagen TV, lam inin, vitronectin, and fibronectin had a similar pattern of expression thro ughout the menstrual cycle in endometrium and endometriosis. Expression of tenascin was elevated in the stroma of the functionalis region of the endom etrium during the proliferative stage of the menstrual cycle and in endomet riosis. Tenascin expression in endometriosis was not modulated according to the stage of the menstrual cycle. It is concluded that expression of tenas cin is strictly regulated in endometrium and may be important in endometria l regeneration and in the pathogenesis of endometriosis. Copyright (C) 1999 John Wiley & Sons, Ltd.