THE EXPRESSION OF p53, c-erbB-2 AND c-yes IN CANINE SKIN TUMORS

Abstract

The exact role of the p53 tumor suppressor gene, c-erbB-2 and c-yes oncogenes in the development of canine skin tumors is still debatable. To elucidate the involvement of these oncogenes in canine skin carcinogenesis, we examined the expression of the protein in 60 skin tumor samples using avidin-biotin complex immunohistochemistry, with polyclonal antibodies directed against each protein, on formalinfixed, paraffin-embedded sections. Positive nuclear staining for p53 protein was observed in 12/60 cases (20%) which included, 6/15(40%) squamous cell carcinomas (SCC) and 4/8(50%) perianal gland tumors (PGT). Out of all the tumors examined, mixed membrane/ cytoplasmic staining of c-erbB-2 protein was found in 17/60 cases (28.3%); 3/15 (20%) of SCC, 3/15 (20%) of basal cell tumors (BCT) and 2/5 (40%) of apocrine gland tumors (AGT). Positive cytoplasmic staining for c-yes protein was detected in 16/60 cases (26.7%); 1/15 (6.7%) of SCC and 7/15 (46.7%) of BCT. The expression of these oncogenes varied with different tumor types. No significant correlation was found among p53, c-erbB-2 and c-yes expression and different histological types of skin tumors.