Expression of HER-2 and nuclear localization of HER-3 protein in canine mammary tumors: histopathological and immunohistochemical study.
HER-2 and HER-3 are transmembrane receptor proteins that are considered to be important but poorly understood biomarkers in canine tumors. In this study, the expression and the localization of HER-2 and HER-3 were evaluated immunohistochemically in canine mammary tumors (n=64; 12 benign, 52 malignant). HER-2 overexpression was identified in 2/12 (16.7%) benign and in 18/51 (35.3%) malignant cases. HER-3 was expressed in a non-nuclear localization in 11/12 (91.7%) benign and 18/52 (34.6%) malignant tumors. In contrast, HER-3 was expressed in the nucleus of neoplastic cells in 0/12 (0%) benign and 22/52 (42.3%) malignant tumors. Nuclear HER-3 expression was higher in neoplastic epithelial cells compared to myoepithelial cells, and positively correlated with high histological grade and lymphatic vessel invasion. These results suggest that nuclear HER-3 expression is significantly associated with tumor progression and metastasis and may serve as a useful prognostic biomarker in canine malignant mammary tumors.
Kim
J H
JH
Department of Veterinary Pathology, Small Animal Tumor Diagnostic Center, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Kwangjin-gu, Seoul 143-701, Republic of Korea.
Im
K S
KS
Kim
N H
NH
Yhee
J Y
JY
Nho
W G
WG
Sur
J H
JH
D000818:Animals; D004283:Dog Diseases / Q000235:genetics* / Q000473:pathology; D004285:Dogs; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D005819:Genetic Markers; D007150:Immunohistochemistry / Q000662:veterinary; D016246:Lymphocytes, Tumor-Infiltrating / Q000473:pathology; D015674:Mammary Neoplasms, Animal / Q000235:genetics* / Q000473:pathology; D060787:Neoplasm Grading / Q000662:veterinary; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D020893:Receptor, ErbB-3 / Q000235:genetics*
D005819:Genetic Markers; D018719:Erb-b2 Receptor Tyrosine Kinases; D020893:Receptor, ErbB-3