CLDN1 and breast carcinoma: β-catenin was selected as a second protein of interest in our TNBC cases because of its close relationship with claudin-1 as two chief components of the Wnt/β-catenin pathway in the development of breast cancer [8], and because of its convergence on the nucleus to combine with a T-cell factor, resulting in increased cellular proliferation in breast cancer [9-10].