Uroplakin III is a 47 kDa glycoprotein present in the urothelial surface membrane of human renal pelvis, ureter, bladder and urethra. Uroplakin III clone BC17 is a newly developed clone, which has demonstrated a higher sensitivity (33/59, 56%), compared with clone AU1 (19/58, 32%) on urothelial transitional cell carcinomas, in in-house studies. With the exception of bladder, BC17 staining was negative in all normal and neoplastic tissues including breast, lung, colon, prostate, kidney, ovarian, liver and pancreatic cancers; therefore, clone BC17 is highly specific to uroepithelial tumors and may be useful in the discrimination of bladder, renal and prostate cancers. Conversely, loss of Uroplakin III expression in bladder cancers has been associated with higher grade, muscle-invasive cancer and lymphovascular invasion. This new Uroplakin III mouse monoclonal is far superior to clone AU1 and may be used in a panel of antibodies including GATA3, p63 and S100P. PATENT PENDING.