title: Identification of molecular phenotypes in canine mammary carcinomas with clinical implications: application of the human classification.
abstract: Similarly to humans, canine mammary cancer represents a heterogeneous group in terms of morphology and biological behaviour. In the present study, we evaluated a series of canine mammary carcinomas based on a new human classification, initially based on gene expression profiling analysis. Similarly to human breast cancer, by using an immunohistochemistry surrogate panel based on five molecular markers [estrogen receptor, human epidermal growth factor receptor 2 (HER2), cytokeratin 5, p63 and P-cadherin], we were able to classify canine mammary carcinomas into four different subtypes: luminal A [estrogen receptor (ER)+/HER2-; 44.8%], luminal B (ER+/HER2+; 13.5%), basal (ER-/HER2- and a basal marker positive; 29.2%) and HER2 overexpressing tumours (ER-/HER2+; 8.3%). Luminal A-type tumours were characterised by lower grade and proliferation rate, whereas basal-type tumours were mostly high grade, high proliferative and positive for cytokeratin 5, p63 and P-cadherin. In addition, as in humans, basal subtype was significantly associated with shorter disease-free and overall survival rates, and we propose canine mammary carcinomas as a suitable natural model for the study of this particular subset of human carcinomas.
authors.affiliation: Department of Veterinary Sciences, CECAV, University of Trás-os-Montes and Alto Douro (UTAD), 5001-811, Vila Real, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Gama
authors.forename: A
authors.initials: A
authors.lastname: Alves
authors.forename: F
authors.initials: F
authors.lastname: Schmitt
mesh_terms: D000818:Animals; D015820:Cadherins / Q000032:analysis; D018572:Disease-Free Survival; D004283:Dog Diseases / Q000145:classification / Q000378:metabolism / Q000473:pathology*; D004285:Dogs; D005260:Female; D020869:Gene Expression Profiling; D016147:Genes, Tumor Suppressor; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D053555:Keratin-5 / Q000032:analysis; D015674:Mammary Neoplasms, Animal / Q000145:classification / Q000378:metabolism* / Q000473:pathology*; D010641:Phenotype; D010750:Phosphoproteins / Q000032:analysis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D011960:Receptors, Estrogen / Q000032:analysis; D015534:Trans-Activators / Q000032:analysis
chemical_list: D015820:Cadherins; D053555:Keratin-5; D010750:Phosphoproteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D015534:Trans-Activators