Aberrant p53 Expression in Feline Vaccine-associated Sarcomas and Correlation with Prognosis

Abstract

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 5 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.

The effects of taurolidine alone and in combination with doxorubicin or carboplatin in canine osteosarcoma in vitro

“…Nuclear accumulation of p53 protein is an indication of mutation in the p53 gene [21,22]. As an initial screen for possible p53 mutants, we used immunocytochemistry to detect abnormal expression of p53 in four canine OS cell lines.…”

Analysis of prognostic factors associated with injection-site sarcomas in cats: 57 cases (2001–2007)

“…5 In general, histologic subtype often correlates with biological behavior; however, in the case of ISSs, the prognostic value of histogenetic classification is questionable. [6][7][8][9] Analysis of prognostic factors associated with injection-site sarcomas in cats: 57 cases (2001)(2002)(2003)(2004)(2005)(2006)(2007) Abbreviations ISS Injection-site sarcoma STS Soft tissue sarcoma Nevertheless, some authors have tried to identify low-and high-risk groups as well as factors associated with survival, metastatic spread, and local tumor recurrence.…”

“…An analysis of prognosis for 61 cats treated by surgery alone was retrospectively provided in a study. 8 The aim of the study reported here was to retrospectively evaluate whether factors such as sex, age, anatomic site of tumor, tumor size, histologic grade, excision of primary tumors or excision of recurrent ISSs, use of excision alone or excision plus adjuvant therapy, and development of local recurrent ISSs or distant metastasis were prognostic factors of survival time in cats with ISSs. In 2 further studies, 9,14 the only significant factor found to be related to disease-free interval was completeness of excision.…”

Musculoskeletal neoplasia

“…2,23,27 Mutations in the p53 gene have been identified 28 and immunohistochemical expression of p53 is also abnormal in FISSs. 29,30 R E V I E W / Musculoskeletal neoplasia in the cat …”