Cancer Diagnostics Solutions
Uroplakin is one of four transmembrane proteins (along with UPIa, UPIb, and UPI specifically expressed in terminally differentiated urothelial cells.
Research has demonstrated that UPI is highly specific for identifying both primary and metastatic urothelial carcinomas. However, the sensitivity of UPI in detecting urothelial carcinoma is only moderate. Therefore, employing a panel of antibodies is crucial for the accurate diagnosis of urothelial tumors.
Uroplakins (UPs), comprising subtypes Ia, Ib, II, and III, are a family of integral transmembrane proteins that serve as terminal differentiation markers of urothelial cells. In non-neoplastic mammalian urothelium, UPs are localized to the apical plasma membrane of superficial (umbrella) cells, where they assemble into highly ordered 16 nm crystalline plaques. Among them, Uroplakin III (UPIII) demonstrates specificity for neoplasms of urothelial origin and, when utilized alongside other immunohistochemical markers, provides diagnostic utility in identifying both primary and metastatic urothelial carcinomas.
A constituent of the asymmetric unit membrane (AUM), a highly specialized biomembrane synthesized by terminally differentiated urothelial cells. This protein is likely involved in mediating interactions between the AUM and the underlying cytoskeletal network, thereby contributing to the structural stability and functional integrity of mature urothelial cells. Additionally, it plays a role in the development of the urothelial glycocalyx, which may serve as a protective barrier by inhibiting bacterial adhesion to the urothelial surface.