title: A preliminary investigation of the role of the transcription co-activators YAP/TAZ of the Hippo signalling pathway in canine and feline mammary tumours.
abstract: Breast cancer is the most common cancer in women worldwide. Cancer metastases are responsible for the high mortality rate. A small but distinct subset of cells, cancer stem cells (CSCs), have the capacity to self-renew, initiate tumour formation, and develop metastases. The CSC content in human breast cancer correlates with the Hippo tumour suppressor signalling pathway. Specifically, the activity of YAP/TAZ, transcription co-activators of the Hippo pathway, sustains the self-renewal and tumour-initiation capacities of CSCs. Little is known about YAP/TAZ in canine and feline mammary tumours, which are very common tumours. The preliminary aim of the study was to investigate the expression of YAP/TAZ in canine and feline mammary tumours by Western blot and immunohistochemistry. Increased cytoplasmic and nuclear expression of YAP/TAZ was observed in all carcinomas compared to normal tissues, indicating neoplastic deregulation of the Hippo pathway. Nuclear expression significantly increased in grade III (high grade carcinomas) compared to grade I (low grade carcinomas) tumours, suggesting that YAP/TAZ play a role in the increased aggressiveness of these tumours. Moreover, different scoring systems for immunohistochemical analyses were compared and the H index and the Allred scores were the most significant. In conclusion, YAP/TAZ are expressed in aggressive canine and feline mammary tumours as reported in some human cancers. Further studies might better elucidate the role of the Hippo pathway in prognosis and as a target for new therapies. In addition, tumours in dogs and cats may be a useful model to study this pathway.
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: G
authors.initials: G
authors.lastname: Beffagna
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: R
authors.initials: R
authors.lastname: Sacchetto
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: L
authors.initials: L
authors.lastname: Cavicchioli
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: A
authors.initials: A
authors.lastname: Sammarco
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: M
authors.initials: M
authors.lastname: Mainenti
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: S
authors.initials: S
authors.lastname: Ferro
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: D
authors.initials: D
authors.lastname: Trez
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy.
authors.forename: M
authors.initials: M
authors.lastname: Zulpo
authors.affiliation: Breast Surgery Unit, Veneto Institute of Oncology IOV - IRCCS, Via Gattamelata, 64 35128 Padua, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Michieletto
authors.affiliation: Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE) University of Padova, Viale dell'Università, 16 35020 Legnaro (PD), Italy.
authors.forename: A
authors.initials: A
authors.lastname: Cecchinato
authors.affiliation: Laboratory of Pathology and Toxicology, Department of Pathobiology, University of Pennsylvania, 3900 Delancy Street, Philadelphia, PA 19104, USA.
authors.forename: M
authors.initials: M
authors.lastname: Goldschmidt
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, 35020 Legnaro (PD), Italy. Electronic address: valentina.zappulli@unipd.it.
authors.forename: V
authors.initials: V
authors.lastname: Zappulli
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D002371:Cat Diseases / Q000378:metabolism*; D002415:Cats; D004283:Dog Diseases / Q000378:metabolism*; D004285:Dogs; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods / Q000662:veterinary; D015674:Mammary Neoplasms, Animal / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction; D014157:Transcription Factors / Q000276:immunology / Q000378:metabolism*
chemical_list: D009363:Neoplasm Proteins; D014157:Transcription Factors
keywords: Cancer stem cells; Immunohistochemistry; Mammary tumours; Scoring systems; Western blot