FGFR3 and urothelial carcinoma: The fibroblast growth factor receptor 3 (FGFR3) gene mutation is highly prevalent in urothelial carcinomas, and the mutant FGFR3 promotes malignant development by over-stimulating the RAS-mitogen-activated protein kinase and phosphatidylinositide-3 kinase–AKT pathway [45, 46].