Expression pattern of c-erbB2 and estrogen receptor-a in spontaneous canine mammary tumours Ranganath G.J.*,3, Kumar Ram3, Reddy A.P. Vishwanatha1,3, Mayilkumar K.3, Pawaiya R.V.S.2,3, Debroy Biplab3 3Division of Pathology, Indian Veterinary Research Institute, Izatnagar-243 122 (U.P.) 1Division of Biochemistry, Indian Veterinary Research Institute, Izatnagar-243 122 (U.P.) 2CIRG, Makhdoom, Mathura (U.P.) *Corresponding author: email: drranganathgjvet@gmail.com
Abstract C-erbB2 and ERa are implicated in carcinogenesis of mammary gland and reproductive tumours. In the present study, expression pattern of c-erbB2 and ERa was investigated in different histological subtypes of spontaneous canine mammary tumour samples by immunohistochemistry (n=103). The pattern of expression of c-erbB2 and ERa was correlated semi-quantitatively with respect to histological subtypes. C-erbB2 overexpression was seen in both membrane and cytoplasm of transformed cells. 33.9% of tumours overexpressed c- erbB2 and its expression was exclusively limited to malignant epithelial tumours. C-erbB2 expression was significantly higher in solid carcinomas, however there was no significant difference between other histological subtypes. ERa expression was found in the nucleus of normal and neoplastic epithelial and myoepithelial cells. 79.6 % of tumours reacted positively for ERa. Simple adenoma had significantly higher levels of ERa expression compared to malignant tumours (P=0.05). Among malignant tumours solid carcinomas and carcinosarcoma had significantly lower ERa expression. However, there was no significant difference in ERa expression between tubular adenocarcinomal papillary adenocarcinoma and malignant mixed tumours. Further, c-erbB2 overexpression was associated either with ER± negativity or its lower expression (P = 0.01). These findings suggest that overexpression of c-erbB2 and loss of ERa expression associated with malignant transformation and higher degree of malignancy. Top Keywords Canine, C-erbB2, ERa, Immunohistochemistry, Mammary tumours. Top |