title: Altered expression of CKs 14/20 is an early event in a rat model of multistep bladder carcinogenesis.
abstract: Cytokeratins (CKs) 14 and 20 are promising markers for diagnosing urothelial lesions and for studying their prognosis and histogenesis. This work aimed to study the immunohistochemical staining patterns of CK14/20 during multistep carcinogenesis leading to papillary bladder cancer in a rat model. Thirty female Fischer 344 rats were divided into three groups: group 1 (control); group 2, which received N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) for 20 weeks plus 1 week without treatment; and group 3, which received BBN for 20 weeks plus 8 weeks without treatment. Bladder lesions were classified histologically. CK14 and CK20 immunostaining was assessed according to its distribution and intensity. In control animals, 0-25% of basal cells and umbrella cells stained positive for CK14 and CK20 respectively. On groups 2 and 3, nodular hyperplastic lesions showed normal CK20 and moderately increased CK14 staining (26-50% of cells). Dysplasia, squamous metaplasia, papilloma, papillary tumours of low malignant potential and low- and high-grade papillary carcinomas showed increased CK14 and CK20 immunostaining in all epithelial layers. Altered CK14 and CK20 expression is an early event in urothelial carcinogenesis and is present in a wide spectrum of urothelial superficial neoplastic and preneoplastic lesions.
authors.affiliation: LEPABE, Departamento de Engenharia Química, Faculdade de Engenharia da Universidade do Porto (FEUP), Porto, Portugal.|Grupo de Patologia e Terapêutica Experimental, CI-IPOP, Instituto Português de Oncologia, Porto, Portugal.
authors.forename: Rui M
authors.initials: RM
authors.lastname: Gil da Costa
authors.affiliation: Departamento de Ciências Veterinárias, Universidade de Trás-os-Montes e Alto Douro (UTAD), Vila Real, Portugal.|CITAB, UTAD, Vila Real, Portugal.
authors.forename: Paula A
authors.initials: PA
authors.lastname: Oliveira
authors.affiliation: Instituto Politécnico de Viseu, Escola Agrária de Viseu, Viseu, Portugal.|CECA, Universidade do Porto, Porto, Portugal.
authors.forename: Carmen
authors.initials: C
authors.lastname: Vasconcelos-Nóbrega
authors.affiliation: CITAB, UTAD, Vila Real, Portugal.
authors.forename: Regina
authors.initials: R
authors.lastname: Arantes-Rodrigues
authors.affiliation: Laboratorio de Citogenética, Departamento de Genética Humana, Centro Hospitalar de Trás-os-Montes e Alto Douro, Vila Real, Portugal.
authors.forename: Rosário
authors.initials: R
authors.lastname: Pinto-Leite
authors.affiliation: Departamento de Ciências Veterinárias, Universidade de Trás-os-Montes e Alto Douro (UTAD), Vila Real, Portugal.|ECAV, UTAD, Vila Real, Portugal.
authors.forename: Aura A
authors.initials: AA
authors.lastname: Colaço
authors.affiliation: Departamento de Fisiologia, Faculdade de Veterinária, Universidade de Santiago de Compostela, Lugo, Spain.
authors.forename: Luis F
authors.initials: LF
authors.lastname: de la Cruz
authors.affiliation: Grupo de Patologia e Terapêutica Experimental, CI-IPOP, Instituto Português de Oncologia, Porto, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopes
mesh_terms: D000818:Animals; D063646:Carcinogenesis / Q000378:metabolism* / Q000473:pathology; D002291:Carcinoma, Papillary / Q000378:metabolism / Q000473:pathology*; D004195:Disease Models, Animal; D005260:Female; D007150:Immunohistochemistry; D053547:Keratin-14 / Q000096:biosynthesis*; D053554:Keratin-20 / Q000096:biosynthesis*; D010212:Papilloma / Q000378:metabolism / Q000473:pathology*; D051381:Rats; D011916:Rats, Inbred F344; D001749:Urinary Bladder Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D053547:Keratin-14; D053554:Keratin-20
keywords: CK14; CK20; bladder cancer; multistep carcinogenesis; rat; stem cell