Expression of matrix metalloproteinases in feline vaccine site-associated sarcomas.

Objectives: To screen for expression of 9 predominant members of the matrix metalloproteinase (MMP) family, including membrane-type matrix metalloproteinases (MT-MMPs) and tissue inhibitors of metalloproteinases (TIMPs), in primary tumor tissue biopsy specimens of vaccine site-associated sarcomas (VSS) in cats and compare expression profiles of VSS with expression profiles of non-VSS and carcinomas.

Sample Population: 31 primary tumor tissue biopsy specimens and 6 nontumor (normal) tissue biopsy specimens.

Procedures: Tissue specimens were obtained from primary tumor biopsy specimens of cats. Primers for reverse transcriptase-polymerase chain reaction assay were designed on the basis of known sequences. Data were analyzed for patterns of expression of MMPs, MT-MMPs, and TIMPs. Differences in expression patterns were evaluated among cats of differing genders, ages, metastasis status, and overall survival durations, and between cats with VSS and cats with non-VSS tumor types.

Results: A total of 31 primary tumor tissue biopsy specimens and 6 nontumor (normal) tissue biopsy specimens were screened for the presence of 6 MMPs and 3 TIMPs. Matrix metalloproteinase and TIMP expression was found in non-VSS, carcinomas, and VSS. No significant differences were found in patterns of expression among tumor types. Metastasis was found to be the only predictive factor for overall survival duration. A significant correlation was found between MMP2 and MT-MMP16 expression and overall duration of survival.

Conclusions And Clinical Relevance: The identification of MMPs in feline VSS supports an underlying inflammatory pathogenesis for this tumor. Expression of MMP2 and MT-MMP16 were correlated with survival time in our study.