title: Immunohistochemical expression of p63 and deltaNp63 in mixed tumors of canine mammary glands and its relation with p53 expression.
abstract: The immunohistochemical expression of p63, DeltaNp63, and p53 was studied in mixed tumors of canine mammary glands (13 benign mixed tumors and 19 carcinomas arising from benign mixed tumors) to determine the role of p63 and its isoform DeltaNp63 in the development of mixed tumors, as well as to assess its relation with p53. P63 was expressed in myoepithelial cells of all benign mixed tumors and in 18 of 19 carcinomas in mixed tumors. The p63-negative carcinoma in mixed tumors was invasive, and a loss of p63 was detected in the other malignant tumors showing a discontinuous p63-stained myoepithelial layer. DeltaNp63 was expressed in all benign mixed tumors but only in p63-positive carcinomas in mixed tumors. Despite its positive correlation with p63 expression in carcinomas in mixed tumors (r = 0.8323, P < .00001), DeltaNp63 expression showed a decrease in benign tumors. Positivity for p53 was detected in 2 of 13 and 1 of 19 benign mixed tumors and carcinomas in mixed tumors, respectively. There was no correlation between p63 or DeltaNp63 and p53 expression. Our data support the notion that the decrease of p63 expression, in particular of its isoform DeltaNp63, seems to be an important factor in the development of carcinomas in mixed tumors.
authors.affiliation: Laboratory of Comparative Pathology, Depto. De Patologia Geral - ICB-UFMG; Cx postal 486, CEP:31270-901, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Bertagnolli
authors.forename: G D
authors.initials: GD
authors.lastname: Cassali
authors.forename: M C L S
authors.initials: MC
authors.lastname: Genelhu
authors.forename: F A
authors.initials: FA
authors.lastname: Costa
authors.forename: J F C
authors.initials: JF
authors.lastname: Oliveira
authors.forename: P B D
authors.initials: PB
authors.lastname: Gonçalves
mesh_terms: D000818:Animals; D002277:Carcinoma / Q000378:metabolism / Q000662:veterinary; D004283:Dog Diseases / Q000235:genetics / Q000378:metabolism; D004285:Dogs; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D007150:Immunohistochemistry / Q000662:veterinary*; D015674:Mammary Neoplasms, Animal / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D018198:Mixed Tumor, Malignant / Q000378:metabolism / Q000662:veterinary*; D020033:Protein Isoforms; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D020033:Protein Isoforms; D016159:Tumor Suppressor Protein p53