Integrins are ubiquitous cell adhesion molecules that undergo dynamic alterations during the normal menstrual cycle in the human endometrium. The αvβ3 vitronectin receptor integrin is expressed in endometrium at the time of implantation, but its presence is delayed in endometrium that is assessed to be out of phase using classical histological features. To investigate the expression of this integrin in women with endometriosis, we assessed the presence of the β3-subunit throughout the menstrual cycle in 268 'in-phase' endometrial biopsies, using immunohistochemistry. The β3-subunit was expressed on endometrial epithelium after days 19-20 of the menstrual cycle. In 241 women whose biopsies were obtained after day 19, a lack of β3 expression was found to be closely related to the diagnosis of endometriosis (by Wilcoxon test, P = 0.02). This defect in integrin expression was associated with nulliparity, inversely related to the stage of disease, and occurred despite the presence of in-phase histological features. In a prospective double blind assessment of this integrin, we found endometrial β3 analysis to have a high specificity and positive predictive value as a nonsurgical diagnostic test for minimal and mild endometriosis. In conclusion, aberrant integrin expression in the native endometrium is associated with the finding of endometriosis and may identify some women with decreased cycle fecundity due to defects in uterine receptivity.
All Science Journal Classification (ASJC) codes
- Endocrinology, Diabetes and Metabolism
- Clinical Biochemistry
- Biochemistry, medical