PIK3CA and breast cancer: We further evaluated nine canonical signaling pathways with frequent oncogenic alterations in Chinese breast cancer, including the cell cycle and the Hippo, Notch, PI-3-kinase (PI3K), β-catenin/Wnt, receptor-tyrosine (RTK)/RAS/MAP-kinase (called RTK-RAS for brevity), p53, TGF-β, and Myc signaling pathways36.