Immunohistochemical detection of tumor suppressor gene p53 protein in feline injection site-associated sarcomas

Sarcomas associated with injection sites are a rare but important problem i n cats. Immunohistochemical detection of p53 protein may correlate to mutat ion of the p53 tumor suppressor gene, a gene known to be important in oncog enesis. The expression of nuclear p53 protein in 40 feline injection site-a ssocated sarcomas was examined by immunohistochemical staining. In 42.5% (1 7/40), tumor cell nuclei were stained darkly; in 20% (8/40), tumor cell nuc lei were stained palely; and in 37.5% (15/40), tumor cell nuclei were unsta ined. Immunohistochemical detection of p53 protein in a proportion of injec tion site-associated sarcomas suggests that mutation of the p53 gene may pl ay a role in the pathogenesis of these tumors.