Changes in uroplakin expression in the urothelium of patients with ulcerative interstitial cystitis/bladder pain syndrome

Purpose: We evaluated changes in the expression of uroplakin (UP) in the urothelium of patients with ulcerative interstitial cystitis/bladder pain syndrome (IC/BPS). Materials and Methods: Bladder samples were collected from 19 patients with ulcerative IC/BPS who were treated with augmentation ileocystoplasty and from 5 control patients. Frequency-volume charts, the pain visual analogue scale (VAS), and the O’Leary- Sant interstitial cystitis symptom index (ICSI) and problem index (ICPI) were used to evaluate the patients’ symptoms preoperatively. The expression levels of UP-Ib and UP-III in the urothelium were compared between the IC/BPS patients and control patients. Results: Sixteen women and three men with IC/BPS were evaluated. Their values for preoperative mean voiding frequency, number of nocturia episodes, and functional bladder capacity as recorded in frequency-volume charts were 21.1±12.8, 5.9±4.2, and 151.1±62.7 mL, respectively. The mean pain VAS, ICSI, and ICPI scores were 8.4±1.3, 17.7±2.2, and 14.7±1.8, respectively. Immunofluorescence staining showed that UP-Ib and UP-III were localized in the urothelium. Upon Western blot analysis, the expression of UP-III was significantly increased in the IC/BPS group compared with the control group. However, expression of UP-Ib did not differ significantly between the IC/BPS and control groups. Conclusions: UP-III was significantly upregulated in patients with ulcerative IC/BPS. UP-III is a potential biomarker for the diagnosis of ulcerative IC/BPS.