Expression of Wnt2b in cholangiocarcinoma and its relationship with epithelial-mesenchymal transition

Objective To study the expression of Wnt2b protein and the epithelial-mesenchymal transition related markers in tissues of carcinoma of bile duct and normal bile duct to determine the clinical significance. The relationships between the expression levels and clinicopathological characteristics were analyzed, and the correlation between Wnt2b and epithelial interstitial transformation (EMT), tumor invasion and metastasis were studied. Methods A total of 60 patients with cholangiocarcinoma and 30 patients with normal bile duct tissues admitted to the Affiliated Hospital of Qingdao University from December 2008 to December 2013 were studied. The expressions of Wnt2b, E-cadherin and Vimentin protein were detected by SP immunohistochemical staining. The patients were classified according to the expressions of these proteins. Analyses were conducted on the relationships of these proteins with clinical characteristics of the patients with cholangiocarcinoma. Results The positive expression rate of Wnt2b protein in carcinoma of bile duct tissues was 90.0%, which was significantly higher than that in normal bile duct tissues (χ2=38.1, P 0.05). Patients with lymph node metastasis had a significantly higher positive expression of Vimentin than patients with no lymph node metastasis, and the loss of E-cadherin expression was increased (all P 0.05). The increased expression of Wnt2b in bile duct cancer cells was related to increase in EMT marker of the positive expression of vimentin and the loss of E-cadherin expression (both P<0.05). Conclusions Wnt2b protein overexpression in cholangiocarcinoma correlated with epithelial-mesenchymal transition related markers. The Wnt2b protein was correlated with cholangiocarcinoma occurrence, development, invasion and metastasis. Wnt2b has the potential to develop into a new therapeutic target for carcinoma of bile duct. Key words: Bile duct neoplasms; Wnt signaling pathway; Epithelial interstitial transformation; Vimentin; E-cadherin