Aberrant expression of Notch1/numb/snail signaling, an epithelial mesenchymal transition related pathway, in adenomyosis

Background: Epithelial mesenchymal transition (EMT) is involved in the pathogenesis of adenomyosis, and Notch signaling is crucial to EMT. The objective of this study was to explore Notch1/Numb/Snail signaling in adenomyosis. Methods: The expression levels of the members of the Notch1/Numb/Snail signaling cascade in normal endometria (proliferative phase: n = 15; secretory phase: n = 15; postmenopausal phase: n = 15) and adenomyotic endometria (proliferative phase: n = 15; secretory phase: n = 15) were determined by immunohistochemistry analysis. Results: We found that the expressions of Notch1 and the EMT-related proteins N-cadherin, Snail and Slug were upregulated in the ectopic endometrium of adenomyosis compared with normal endometrium. Numb, a negative regulator of Notch signaling, was significantly decreased in adenomyosis. In addition, reduced immunoexpression of E-cadherin was observed in adenomyosis. Conclusions: We conclude that Notch1/Numb/Snail signaling plays an important role in the pathogenesis and development of adenomyosis.