Aberrant p53 expression in feline vaccine-associated sarcomas and correlation with prognosis.

TitleAberrant p53 expression in feline vaccine-associated sarcomas and correlation with prognosis.
Publication TypeJournal Article
Year of Publication2005
AuthorsHershey AE, Dubielzig RR, Padilla ML, Helfand SC
JournalVeterinary pathology
Volume42
Issue6
Pagination805-11
Date Published2005 Nov
ISSN0300-9858
KeywordsAnimals, Cat Diseases, Cats, Immunohistochemistry, Sarcoma, Tumor Suppressor Protein p53, Vaccination
Abstract

Eighty spontaneously occurring feline vaccine-associated sarcomas (VAS) were evaluated to determine the immunohistochemical expression of the tumor suppressor gene p53. Sixty-five of 80 VAS (81%) exhibited positive immunoreactivity with Mab240, a murine monoclonal antibody that specifically recognizes mutated p53. Only 44 of 81 tumors (55%) were positive with rabbit polyclonal antibody CM-1. CM-1 often yielded nonspecific staining of nonneoplastic tissues. Nonspecific staining was greatly reduced or absent with Mab240. Cytoplasmic staining for p53 was a consistent pattern of VAS, occurring in 44% of tumors evaluated. Cats with tumors that exhibited cytoplasmic p53 had significantly shorter time to tumor recurrence compared to those cats with tumors that exhibited nuclear p53 staining (P = 0.0284), but no significant difference in survival outcome was observed. Immunohistochemical detection of p53 offers a prognostic tool for VAS, and, because abnormal p53 expression appears to be a common feature of feline VAS, molecular targeting of mutant p53, may offer a promising new therapeutic opportunity for this cancer.

Alternate JournalVet. Pathol.