Abstract
Studies of the urothelium, the specialized epithelial lining of the urinary bladder, are critical for understanding diseases affecting the lower urinary tract, including interstitial cystitis, urinary tract infections and cancer. However, our understanding of urothelial pathophysiology has been hampered by a lack of appropriate model systems. Here, we describe the isolation and characterization of a non-transformed urothelial cell line (TRT-HU1), originally explanted from normal tissue and immortalized with hTERT, the catalytic subunit of telomerase. We demonstrate responsiveness of the cells to anti-proliferative factor (APF), a glycopeptide implicated in the pathogenesis of interstitial cystitis. TRT-HU1 carries a deletion on the short arm of chromosome 9, an early genetic lesion in development of bladder cancer. TRT-HU1 urothelial cells displayed growth and migration characteristics similar to the low-grade papilloma cell line RT4. In contrast, we observed marked differences in both phenotype and gene expression profiles between TRT-HU1 and the highly malignant T24 cell line. Together, these findings provide the first demonstration of a non-transformed, continuous urothelial cell line that responds to APF. This cell line will be valuable for studies of both benign and malignant urothelial cell biology.