PIK3CA and cancer: For instance, the top 30 enriched pathways ranked by FDR in TCGA pan-cancer include well-known cancer pathways such as the ErbB signaling pathway, cell-cycle regulation, apoptosis regulation, p53 signaling pathway, MAPK signaling pathway, mTOR signaling pathway, Ras signaling pathway, PI3K-Akt signaling pathway, regulation of mitotic cell cycle and epithelial cell proliferation (Figure 5A, Supplementary Figure S4A).