Identification of SLC14A1 (UT-B) gene rearrangement in urothelial carcinoma of the bladder

Abstract

Background: Bladder cancer (BCa) is a common and deadly disease. Over the past decade, a number of genetic alterations have been reported in BCa. Bladder urothelium expresses abundant urea transporter UT-B encoded by Slc14a1 gene at 18q12.3 locus, which plays an important role in preventing high concentrated urea-caused cell injury. Early genome-wide association studies (GWAS) showed that UT-B gene mutations are genetically linked to the urothelial bladder cancer. Methods: In this study, using a fluorescence in situ hybridization (FISH), we examined whether Slc14a1 gene has been changed in BCa with Slc14a1 break-apart DNA probes. We also performed immunohistochemistry evaluating bladder cancer markers. Results: We found Slc14a1 gene rearrangement in one case of BCa from 14 patients. The patient is a 59-year-old male with superficial BCa. Histology showed non-muscle invasive bladder transitional-cell carcinoma. Immunostaining was negative for Syn, CK7, CK20, Villin, and positive for HER2, BRCA1, GATA3. Conclusions: We for the first time report a patient diagnosed with urothelial carcinoma accompanied with split Slc14a1 gene abnormality, a crucial gene in bladder.