The Endometriotic Nodule Has Lower T-cadherin, E-cadherin, Progesterone Receptor and Oestrogen Receptor Than Endometrioma Tissue

Abstract Objective: To compare the T-cadherin, E-cadherin, PR and ER staining levels of endometriotic nodules, ovarian endometriomas and normal endometrial tissues. Methods: Endometriotic nodules of 24 cases, endometrioma of 30 cases and normal endometrial tissues of 30 cases were examined. T-cadherin, E-cadherin, ER-α and PR-α staining levels of endometriotic nodular tissues, endometrioma tissues and endometrial tissues were compared immunohistochemically. H -score was calculated to compare the expression of T-cadherin, E-cadherin, ER-α, PR-α in IHC staining based on the percentage of cells stained at each intensity level. Results: T-cadherin, E-cadherin, ER and PR H-score were found lowest in endometriotic nodule tissue and the highest in endometrial tissue (p <0.0001, <0.0001, <0.0001 and <0.0001, respectively). In correlation analysis, a positive correlation was found between T-cadherin, E-cadherin, PR and ER H-score (p 0.05). Conclusions: T-cadherin, E-cadherin, ER and PR H -score were found lowest in endometriotic nodule tissue, the highest in endometrium tissue. The finding of lower expression of PR-α in endometriotic nodule in our study may be related to decrease in progesterone effect which could not inhibit the decrease in the expression of T-cadherin and E-cadherin, thus the invasiveness of endometriotic nodule. These findings suggest that endometriotic nodule and ovarian endometrioma tissues have a different biology.