UPK3A and Ureteral obstruction: Indeed, urothelium proliferation was reported to occur early within specialized fornices following renal ischemic injuries, ureteral obstruction or stimulation by pharmacologic agents such as FGF7 via activation of urothelial FGFR2IIIb membrane receptors8,9, resulting into the loss of apical UPIII plaques, increased membrane permeability, luminal membrane roughness, urothelial cells multilayer and urothelial desquamation.