Immunocytochemical analysis of the tumour suppressor protein (p53) in feline neoplasia

Detectable p53 immunostaining in neoplasia generally correlates with the pr esence of a mutation in the coding region of the p53 gene and may provide i nsights into the pathogenic mechanisms underlying tumourigenesis. p53 immun oreactivity was examined in 77 feline tumours, selected as a representative sample of 486 specimens submitted for diagnosis and analyzed to estimate t he relative frequencies of feline neoplasias. Immunocytochemical staining d emonstrated nuclear immunopositivity in 46% of the squamous cell carcinomas (SCCs), 50% of the osteosarcomas, 33% of the mammary carcinomas, 16% of th e adenocarcinomas and 14% of the haemangiosarcomas. In contrast, none of th e malignant lymphomas or fibrosarcomas examined showed p53 immunoreactivity . These data support a role for p53 aberrations in the pathogenesis of cert ain feline tumours. (C) 2000 Elsevier Science Ireland Ltd. All rights reser ved.