Analysis of ADAM12 in the endometrium and ADAM12 Levels in Serum and Endocervical Mucus of Endometriosis

Abstract

Endometriosis is an estrogen-responsive disease defined as the presence of endometrial glands and stroma outside the uterine cavity, predominantly but not exclusively in the pelvic compartment. Its main clinical features comprise chronic pelvic pain, dyspareunia and infertility. A disintegrin and metalloproteinases (ADAMs) are a family of membrane anchored cell surface glycoproteins that are responsible for proteolysis, cell adhesion and metastasis of tumor cells. In this study, we investigated localization of ADAM12 in the eutopic and ectopic endometrium (n = 136) using immunohistochemistry. We also analyzed ADAM12 levels in serum (n = 293) and endocervical mucus (n = 79) of women with and without endometriosis using ELISA. A preferential localization of ADAM12 in the glandular and the luminal epithelial cells in the eutopic endometrium with and without endometriosis as well as in ectopic endometrium was observed. Additionally, ADAM12 was found to localize in the endothelial cells of blood vessels and smooth muscle cells of the myometrial layer of eutopic endometrium. Localization of ADAM12 showed no differences in eutopic endometrium of controls compared to those with endometriosis. Similarly, serum and endocervical mucus ADAM12 levels were not different between women with and those without endometriosis, although endocervical mucus ADAM12 levels were significantly lower than serum levels in paired samples. Collectively, our results show that localization of ADAM12 is highly stable in eutopic and ectopic endometrium without any loss of the epithelial phenotype and therefore is unlikely to contribute to the pathogenesis of endometriosis.