Regulation and activation of ezrin protein in endometriosis.

BACKGROUND Ezrin protein and its activated form phospho-ezrin play a role in cell morphology, motility and adhesiveness. In this study, we hypothesized that these proteins play a role in the pathogenesis of endometriosis by promoting adhesion and invasion of endometrial stromal cells (ESCs) in ectopic sites. METHODS We compared the expression of ezrin and phospho-ezrin in normal endometrium from women without endometriosis with their expression in eutopic and ectopic endometrial tissues from women with endometriosis, using immunohistochemistry and western blot analysis. Paired eutopic and ectopic endometrial tissue samples from women with endometriosis (n = 13) and normal endometrium from women without endometriosis (n = 12) were collected. Invasive potential of ESCs from each of these samples was compared using Matrigel membrane invasion assay. RESULTS Eutopic and ectopic endometrial tissues from women with endometriosis have higher ezrin and phospho-ezrin levels as confirmed by immunohistochemistry and western blot analysis (P < 0.05). The Matrigel membrane invasion assay revealed that ectopic ESCs have more invasive characteristics, more protrusions and higher ezrin staining than normal ESCs (P < 0.05). CONCLUSIONS Ezrin can be a potential marker for endometrial cell invasion and may play a role in the pathogenesis of endometriosis.