Low endometrial beta-catenin and cadherins expression patterns are predictive for primary infertility and recurrent pregnancy loss

Inadequate uterine receptivity is responsible for two-third of implanting failures. Aim of the study was to investigate the role of epithelial adherence and tight-junction molecules expressed by human endometrium in predicting womens' fertility outcome. A total of 76 consecutive women, including 24 fertile (G1), 40 primary infertile (G2), and 12 recurrent pregnancy loss (RPL, G3) women, who underwent diagnostic hysteroscopy plus endometrial biopsy between 2005 and 2016 at the Gynecology Division of Sant'Andrea Hospital, Sapienza University of Rome, in Italy, were retrospectively identified and included into the study. Endometrial biopsies were assessed for the immunohistochemical expression of beta-catenin (β-catenin), E-cadherin and K-cadherin biomarkers. Expression profiles were compared between the three groups of patients and were correlated with patients' fertility outcome. In infertile patients there was a significant lower endometrial expression of β-catenin (p = .001), E-cadherin (p = .001) and K-cadherin (p = .002), compared to the fertile ones. Furthermore, β-catenin and E-cadherin intensity gradients of expression at glandular level were found totally reversed in infertile patients. Significant lower expression levels of K-catenin (p = .016) and E-cadherin (p < .0001) at glandular level were found in RPL patients. Results showed that the low endometrial expression of β-catenin, E-cadherin and K-cadherin were associated to fertility-related problems, such as primary intertility and RPL.