Uroplakin Expression in the Urothelial Tumors of Cows

Abstract

Abstract. Expression of uroplakins (UPs) was investigated in 20 bladder tumors from cows that had been suffering from chronic enzootic hematuria for several years. In dysplastic urothelium and papillomatous proliferations, UP expression was evident both as luminal and intercellular staining. Chronic enzootic hematuria is a clinical syndrome of cattle caused by prolonged ingestion of some toxic substances from bracken fern (Pteridium spp.). Epithelial and mesenchymal tumors of the urinary bladder are frequently associated with this syndrome. Uroplakins (UPs) are major specific urothelial differentiation products of mammalian urothelium. 5,10 They are mainly produced in cells of the superficial layer of transitional cell epithelium, and they consist of four components: the 27-kd UP Ia, the 28-kd UP Ib, the 15-kd UP II, and the 47-kd UP III. 12,13 UPs are conserved through a broad range of mammalian species and are the major protein components of the asymmetric unit membrane (AUM). 11 The AUM forms the apical plaques of mammalian urothelium 1 and may act as a permeability barrier; it also may act as a means of stabilizing the apical bladder surface. 9 It has been suggested that the ability of the urothelium to terminally differentiate is gradually lost in neoplastic processes, so UPs may be a useful morphologic biomarker of differentiation in bladder carcinogenesis. 14 The aim of the present study was to investigate UP expression immunohistochemically in spontaneous tumors of the urothelium in cows grazing on bracken fern-infested land in southern Italy. Materials and MethodsSamples of neoplastic urothelium were obtained at public slaughterhouses from twenty 4-16-year-old cows that had been suffering from chronic enzootic hematuria for several years. All the animals were known to have grazed on bracken-infested pasture because they were raised in mountain areas. Urothelium, uterus, vagina, fallopian tube, ovary, and mammary gland from five 4-14-year-old healthy cows were also examined as controls. These control animals came from lowlands, where bracken fern is virtually absent. Tissues were fixed in 10% buffered formalin and processed routinely for paraffin embedment. The avidin-biotin-peroxidase complex method was used for immunohistochemical analysis of UP. Immunofluorescence staining for confocal laser scanning microscopic investigations was also performed. Five-micrometer-thick sections were blocked for endogenous peroxidase in 0.3% H 2 O 2 in methanol for 20 minutes. Antigen was enhanced by pretreating with microwave heating (twice for 5 minutes each at 750 W). Anti-AUM antibody reacting with all four UPs (Dr. T. T. Sun, Epithelial Biology Unit, Ronald Perelman Department of Dermatology. Department of Pharmacology and Kaplan Comprehensive Cancer Center. New York University School of Medicine, New York, NY) was made against highly purified bovine AUM and applied overnight at 4 C at a 1 : 2,000 dilution. Slides were washed three times, incubated with secondary antibody (biotinylated goat anti-rabbit IgG, Dako, D...

Immunohistochemical Expression of Cyclin D1, Cytokeratin 20, and Uroplakin III in Proliferative Urinary Bladder Lesions Induced by o-Nitroanisole in Fischer 344/N Rats

“…Some degree of UPIII expression loss in the superficial cells, noted sporadically as discontinuity in papillomas and carcinomas in the present study, is associated with increasing tumor development, grade, or stage in human, canine, bovine, and chemically induced mouse and rat urothelial tumors. 1,9,18,23,28 The loss of UPIII immunoreactivity was minimal in the present study, and UPIII loss in chemically induced urothelial neoplasms has been found to be greater in mice than rats. 23 In a large study in humans, negative UPIII expression was significantly associated with risk of recurrence and cancer-specific mortality in cases of muscleinvasive urothelial carcinomas but not in noninvasive carcinomas.…”

“…The increase in immunoreactivity in intermediate cells and in a patchy pattern has also been observed in chemically induced rat bladder neoplasia in other studies, as well as in some human, bovine, and canine urothelial carcinomas. 1,13,23,26,28 There are several possible reasons for the remarkable increase in the number of intermediate cells with strong membranous or cytoplasmic UPIII immunoreactivity in hyperplastic and neoplastic lesions. First, immunoreactive intermediate cells may have elevated, rather than decreased, uroplakin synthesis.…”

Bovine papillomavirus E5 oncoprotein binds to the activated form of the platelet-derived growth factor β receptor in naturally occurring bovine urinary bladder tumours

“…The antibodies for these tissue markers recognized the respective antigens in Western blots of protein lysates from bladder tumours (data not shown). Uroplakin III is a highly specific marker for urothelial tumours, including human, canine and bovine tumours (Kaufmann et al, 2000;Ambrosio et al, 2001;Ramos-Vara et al, 2003;Roperto et al, 2005). The expression of PDGF b receptor in the urothelium was confirmed by its coexpression with cytokeratins ( Figure 2d-f) and with the few cells expressing uroplakin III (Figure 2g-i).…”

Altered expression of UPIa, UPIb, UPII, and UPIIIa during urothelial carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine in rats

“…Their results, combined with data of human, mouse, canine, and cow carcinogenesis [22][23][24][25], suggest that uroplakin downregulation does not strictly parallel urothelial tumorigenesis and progression. All of the existing studies were limited to the use of antibodies that mainly recognize UPIIIa, i.e., anti-AUM or anti-UPIIIa antibody [22][23][24][25].…”

“…For example, Ogawa et al showed that in N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced urothelial carcinogenesis of rats, the expression of total uroplakins in superficial cells is decreased but the expression in some intermediate cells is increased [22]. Their results, combined with data of human, mouse, canine, and cow carcinogenesis [22][23][24][25], suggest that uroplakin downregulation does not strictly parallel urothelial tumorigenesis and progression. All of the existing studies were limited to the use of antibodies that mainly recognize UPIIIa, i.e., anti-AUM or anti-UPIIIa antibody [22][23][24][25].…”