title: Comparison of uroplakin expression during urothelial carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine in rats and mice.
abstract: The expression of uroplakins, the tissue-specific and differentiation-dependent membrane proteins of the urothelium, was analyzed immunohistochemically in N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-treated rats and mice during bladder carcinogenesis. Male Fischer 344 rats were treated with 0.05% BBN in the drinking water for 10 wk and were euthanatized at week 20 of the experiment. BBN was administered to male B6D2F, mice; it was either provided at a rate of 0.05% in the drinking water (for 26 wk) or 5 mg BBN was administered by intragastric gavage twice weekly for 10 wk, followed by 20 wk without treatment. In rats, BBN-induced, noninvasive, low-grade, papillary, transitional cell carcinoma (TCC) showed decreased uroplakin-staining of cells lining the lumen but showed increased expression in some nonluminal cells. In mice, nonpapillary, high-grade dysplasia, carcinoma in situ, and invasive carcinoma were induced. There was a marked decrease in the number of uroplakin-positive cells lining the lumen and in nonluminal cells. This occurred in normal-appearing urothelium in BBN-treated mice and in dysplasic urothelium, in carcinoma in situ, and in invasive TCC. The percentage of uroplakin-positive nonluminal cells was higher in control mice than in rats, but it was lower in the mouse than in the rat after BBN treatment. Uroplakin expression was disorderly and focal in BBN-treated urothelium in both species. These results indicate that BBN treatment changed the expression of uroplakins during bladder carcinogenesis, with differences in rats and mice being related to degree of tumor differentiation.
authors.affiliation: Department of Pathology and Microbiology and the Eppley Institute for Research in Cancer, University of Nebraska Medical Center, Omaha 68198-3135, USA.
authors.forename: K
authors.initials: K
authors.lastname: Ogawa
authors.forename: M
authors.initials: M
authors.lastname: St John
authors.forename: M
authors.initials: M
authors.lastname: Luiza de Oliveira
authors.forename: L
authors.initials: L
authors.lastname: Arnold
authors.forename: T
authors.initials: T
authors.lastname: Shirai
authors.forename: T T
authors.initials: TT
authors.lastname: Sun
authors.forename: S M
authors.initials: SM
authors.lastname: Cohen
mesh_terms: D000818:Animals; D002085:Butylhydroxybutylnitrosamine; D015197:Carcinogenicity Tests; D002273:Carcinogens; D002277:Carcinoma / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D002452:Cell Count; D007150:Immunohistochemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D008565:Membrane Proteins / Q000096:biosynthesis; D051379:Mice; D051381:Rats; D011916:Rats, Inbred F344; D059470:Tetraspanins; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D060170:Uroplakin II; D060171:Uroplakin III; D060167:Uroplakin Ia; D060169:Uroplakin Ib; D019459:Urothelium / Q000378:metabolism* / Q000473:pathology
chemical_list: D002273:Carcinogens; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D059470:Tetraspanins; C086452:UPK1B protein, human; C554658:UPK2 protein, human; C490123:Upk1a protein, mouse; C490124:Upk1b protein, mouse; C554659:Upk2 protein, mouse; D060170:Uroplakin II; D060171:Uroplakin III; D060167:Uroplakin Ia; D060169:Uroplakin Ib; D002085:Butylhydroxybutylnitrosamine