p63: A novel myoepithelial cell marker in canine mammary tissues

• Type: Article in International Scientific Journal
• Date: 2003

Authors

Gama, A (Author) Other; Alves, A (Author) Other; Fátima Gärtner (Author) ICBAS; Fernando Schmitt (Author) FMUP

Journal

Title: Veterinary Pathology

Vol. 40

Pages: 412-420

ISSN: 0300-9858

Publisher: SAGE

Indexing

ISI Web of Knowledge - 76 Citations

Scopus - 91 Citations

Other information

Authenticus ID: P-000-G64

DOI: 10.1354/vp.40-4-412

Abstract (EN): Several immunohistochemical markers have been used to demonstrate the presence of myoepithelial cells in order to determine their role in the histogenesis of mammary tumors. p63, a recently characterized p53 homologue, is consistently expressed in myoepithelial cells of the human breast; however, no assessment of its immunoreactivity has been reported so far in canine mammary tissues. We investigated p63 immunohistochemical expression, as a novel myoepithelial cell nuclear marker, in 81 samples of normal (n = 2), hyperplastic (n = 11), and neoplastic (n = 68) canine mammary tissues. Myoepithelial phenotype was confirmed by using complementary monoclonal antibodies: alpha-smooth muscle actin, cytokeratin 14, cytokeratin AE1/AE3, and vimentin. p63 expression was observed in 91.4% (74/81) of the samples evaluated. Normal mammary glands, mammary hyperplasias, and benign tumors showed 100% immunoreactivity, with p63 expression restricted to myoepithelial cell nuclei. In general, benign mixed tumors showed a basal cell compartment immunoreactive to p63, with a gradual decrease of its expression during myoepithelial transformation. p63 expression was found in 72% of malignant tumors, allowing myoepithelial or basal cell identification in spindle-cell carcinomas (2/2), tubulopapillary carcinomas (8/9), solid carcinomas (7/10), and carcinosarcomas (1/3). The osteosarcoma analyzed was p63 negative. In our series, stromal components were consistently nonreactive to p63. In conclusion, the present study reveals p63 as a sensitive and highly specific marker of myoepithelial cells in canine mammary tissues, and the authors suggest p63 as an additional marker for defining myoepithelial histogenesis.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9