FGFR2 and neoplasm: Fibroblast growth factor receptor-2 (FGFR2), a member of the RTK family, regulates cell proliferation and angiogenesis and is amplified in 4–10% of esophageal and gastric cancers.76 Phosphatidylinositol 3-kinase (PI3K) is a lipid kinase that can regulate the growth, proliferation, and migration of tumor cells.