CDH1 and Bartsocas-Papas syndrome 1: Abnormal expression of cell adhesion proteins (uroplakins, chondroitin sulfate), tight junction protein zonula occludens-1 (ZO-1), E-cadherin, and bacterial defense molecule (GP51) in the bladder tissues of patients with IC/BPS strongly suggest abnormal differentiation in the bladder with IC/BPS [18,23].