HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology

 

Immunohistochemical evaluation of versican, in relation to chondroitin sulphate, in canine mammary tumours

I. Erdélyi1, D.H.M. Nieskens1, J.E. van Dijk1, L. Vass2 and H. Nederbragt1

1Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University,Utrecht, The Netherlands and 2P.M.Flór Ferenc Hospital, Division of Pathology-Histopathology-Cytology, Kistarcsa, Hungary

Offprint requests to: I. Erdélyi, Department of Pathobiology, Faculty of Veterinary Medicien, Utretcht University, P.B. 80.158, 3508 TD Utrecht, The Netherlands. e-mail: I.Erdelyi@vet.uu.ul

 

Summary. The expression of increased amounts of versican, a chondroitin sulphate proteoglycan, in neoplastic tissues may play a role in promoting tumour cell proliferation and migration. This study investigated the immunolocalization of versican in normal and neoplastic canine mammary tissues, using antibodies 12C5 and 2B1, against different epitopes of the protein core of versican. Antibody CS56, recognising chondroitin sulphate (CS), was used to investigate the relation between versican and CS, which accumulates in canine mammary tumours. We found enhanced versican expression in both benign and malignant tumours, appearing in three main patterns: in periductal tissues, probably in association with basement membranes of ducts; in peripheral invasive areas of malignant tumours; and in spindle cell proliferations and myxoid areas of complex and mixed tumours. The 12C5 and 2B1 immunoreactivities co-localised in all types of tumours, and could be improved by chondroitinase digestion. The only exception was the abundant extracellular matrix (ECM) of spindle cell proliferations, particularly in myxoid areas of complex and mixed tumours, which displayed intense and diffuse 12C5 immunoreactivity and patchy or absent 2B1 and CS56 immunoreactivities; versican immunoreactivity could not be enhanced by chondroitinase digestion. The results indicate that versican is one of the extracellular matrix components characteristic of canine mammary tumours. It appears likely that in complex and mixed tumours versican exists in at least two forms, one of them lacking the CS attachment domain and the 2B1 epitope. Furthermore, the enhanced versican expression in the invasive areas of malignant tumours indicates the involvement of this proteoglycan in tumour cell invasion. Histol. Histopathol. 18, 1067-1080 (2003)

Key words: Versican, Chondroitin sulphate, Proteoglycan, Extracellular matrix, Canine mammary tumour

DOI: 10.14670/HH-18.1067