The molecular mechanisms driving FGFR3 protein overexpression in UC are also still largely unknown, although a recent study has shown that FGFR3 expression in urothelial cells is regulated by two microRNAs (miR-99a/100), which are often downregulated in UC, particularly in low-grade and low-stage tumours [55]. Here, FGFR3 is linked to neoplasm.