Uroplakins (UPs) are a family of transmembrane proteins (UPs Ia, Ib, II and III) that are specific differentiation products of urothelial cells. In non-neoplastic mammalian urothelium, UPs are expressed in the luminal surface plasmalemma of superficial (umbrella) cells, forming complexes of 16-nm crystalline particles. Moll et al. reported that UPIII was detectable immunohistochemicall
y in 29 of 55 primary (53%) and 23 of 35 metastatic (66%) urothelial carcinomas, whereas many non-urothelial carcinomas were UPIII-negative. The authors concluded that UPIII should be a valuable marker, especially for the specific identification of urothelial carcinomas in patients with metastases of unknown primary site.
Uroplakins (UPs) are a family of transmembrane proteins (UPs Ia, Ib, II and III) that are specific differentiation products of urothelial cells. In non-neoplastic mammalian urothelium, UPs are expressed in the luminal surface plasmalemma of superficial (umbrella) cells, forming complexes of 16-nm crystalline particles. Moll et al. reported that UPIII was detectable immunohistochemically in 29 of 55 primary (53%) and 23 of 35 metastatic (66%) urothelial carcinomas, whereas many non-urothelial carcinomas were UPIII-negative. The authors concluded that UPIII should be a valuable marker, especially for the specific identification of urothelial carcinomas in patients with metastases of unknown primary site.
