APC and breast neoplasm: In this study, we have described APC/β-catenin-rich clusters at protrusion ends in multiple models, including 1) epithelial cells in which endogenous β-catenin has been stabilized, 2) epithelial cells undergoing EMT and 3) mouse and human breast tumor cell lines, all of which have a mesenchymal morphology with robust membrane protrusions.