Involvement of α- and ß-catenins and E-cadherin in the development of mammary phyllodes tumours

Aims: Phyllodes tumours (PT) are rare but clinically important fibroepithelial tumours of the breast. beta-Catenin, a key component in Wnt signalling, has been shown to be important in the development of PT. It also functions as a component of the cadherin complex, which may therefore be implicated in PT pathogenesis. By assessing stromal alpha-catenin, beta-catenin and E-cadherin expression in 158 PT cases using immunohistochemistry and examining associations with clinicopathological features, we aimed to determine the role of these proteins in PT pathogenesis. Methods and results: Cytoplasmic beta-catenin correlated with alpha-catenin expression. A significantly higher expression of both markers was observed in borderline than in benign PT (P = 0.003 and