Aberrant expression of several other urothelial growth-related factors, which contribute to the bladder integrity and impermeability (131), such as GAGs, glycoproteins (e.g., GP51, GP1) (132, 133) proteoglycan core proteins (biglycan, decorin, perlecan, and syndecan-1), keratins (134, 135), and uroplakins (e.g., III-delta4) (131, 136), have been revealed in IC/BPS cases as well. The gene discussed is HSPG2; the disease is Bartsocas-Papas syndrome 1.