Concurrent expression of cyclo-oxygenase-2 and epidermal growth factor receptor in canine malignant mammary tumours.
Canine mammary tumours (CMTs) are reported to express cyclo-oxygenase (COX)-2 and epidermal growth factor receptor (EGFR); however, no studies have evaluated concurrent expression of these proteins. In this study, 43 malignant CMTs were evaluated immunohistochemically for concurrent expression of COX-2 and EGFR and expression was correlated with malignancy. High COX-2 expression was associated with tumour size (P = 0.033), mitotic index (P = 0.040), nuclear grade (P = 0.021), histological grade of malignancy (P = 0.020) and lymph node metastasis (P = 0.029). High EGFR immunoreactivity was associated with tumour size (P = 0.001), necrosis (P = 0.001), mitotic index (P = 0.022), histological grade of malignancy (P = 0.041) and lymph node metastasis (P = 0.005). Simultaneous high-expression of COX-2 and EGFR was associated with high-nuclear grade (P = 0.049), high-histological grade of malignancy (P = 0.031) and the presence of lymph node metastasis (P = 0.025). A positive correlation between COX-2 and EGFR expression (r = 0.474; P = 0.001) was also observed. These results suggest that combined use of selective inhibitors of COX-2 and EGFR may be a useful approach to the treatment of malignant CMTs.
Instituto de Ciências Biomédicas de Abel Salazar, University of Porto, 4099-003 Porto, Portugal.
M J
MJ
Guimarães
Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, 5001-801 Vila Real, Portugal.
M I
MI
Carvalho
Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, 5001-801 Vila Real, Portugal.
I
I
Pires
Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, 5001-801 Vila Real, Portugal.
J
J
Prada
Fisiologia Animal, Universidad Complutense de Madrid, Spain.
A Gonzalez
AG
Gil
Instituto de Ciências Biomédicas de Abel Salazar, University of Porto, 4099-003 Porto, Portugal.
C
C
Lopes
Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, 5001-801 Vila Real, Portugal; CECA, University of Porto, Porto, Portugal. Electronic address: fqueirog@utad.pt.
F L
FL
Queiroga
D000818:Animals; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D004283:Dog Diseases / Q000378:metabolism* / Q000473:pathology; D004285:Dogs; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D007150:Immunohistochemistry; D015674:Mammary Neoplasms, Animal / Q000378:metabolism* / Q000473:pathology
D051546:Cyclooxygenase 2; D066246:ErbB Receptors
COX-2; EGFR; canine mammary tumours; therapeutic target