PIK3CA and neoplasm: Upon binding of EGF or other ligands, EGFR is activated and induces the activation of downstream signaling pathways, including Ras-MAPK, PI3K/Akt, JAK/STAT, and PLCγ/PKC pathways, which leads to tumor cell proliferation, angiogenesis, tumor invasion, metastasis, and inhibition of apoptosis [2, 3].