ERBB2 and breast cancer: Aberrant Wnt/β-catenin signaling is associated with a poorer prognosis in breast cancer patients [46], and is predominantly found in triple negative breast cancer (TNBC) which is distinguished by negative immunohistochemical assays for expression of the estrogen and progesterone receptors (ER/PR) and human epidermal growth factor receptor-2 (HER2) [47, 48, 49].