Downregulation of WNT11 is associated with bladder tissue fibrosis in patients with interstitial cystitis/bladder pain syndrome without Hunner lesion

This study assessed the functional role of WNT genes and the association between WNT signalling cascades and fibrosis in interstitial cystitis/bladder pain syndrome (IC/BPS) patients. Twenty-five patients (3 males, 22 females; mean age 59. 7 ± 10.9 years), included 7 non-Hunner-type IC (NHIC), 18 Hunner-type IC (HIC), and 5 non-IC (control) groups. The expression of sonic hedgehog, WNT gene family, and genes previously reported as biomarkers for IC/BPS were examined using RT-PCR in biopsy specimens from the mucosa and submucosa layer of the bladder. WNT2B, WNT5A, WNT10A, and WNT11 functions in the urothelium were evaluated by silencing in an HBlEpC cell line. Pelvic Pain and Urgency/Frequency Patient Symptom Scale scores, O'Leary-Sant Symptom and Problem Index scores, and Visual Analogue Scores did not differ between the NHIC and HIC groups. However, HIC patients had significantly shorter symptom duration (30.9 vs 70.8 months, p = 0.046), higher daily urinary frequency (16.1 versus 8.5 times, p = 0.006), and smaller bladder capacity (208.6 versus 361.4 ml, p = 0.006) than NHIC patients. Overall WNT gene expression was lower in NHIC than HIC patients. Bladder epithelial tissues from HIC patients were characterised by the downregulation of WNT11. Silencing of WNT11, WNT2B, WNT5A, and WNT10A in HBlEpCs resulted in fibrotic changes, indicated by fibrotic morphology, increased fibrosis-related gene expression, and nuclear localisation of phosphorylated SMAD2, and increased vimentin and fibronectin levels. Downregulation of WNT11 results in fibrotic changes of bladder epithelial cells and is associated with the pathogenesis and differential diagnosis of NHIC. Decreased expression of WNT11 is a potential biomarker for predicting NHIC.

Scientific reports. 2018 Jun 28*** epublish ***

Daeheon Choi, Ju-Young Han, Jung Hyun Shin, Chae-Min Ryu, Hwan Yeul Yu, Aram Kim, Seungun Lee, Jisun Lim, Dong-Myung Shin, Myung-Soo Choo

Department of Urology, University of Ulsan College of Medicine, Seoul, Korea., Department of Urology, Konkuk University Hospital, Konkuk University School of Medicine, Seoul, Korea., Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea., Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Korea. ., Department of Urology, University of Ulsan College of Medicine, Seoul, Korea. .