Final report, Winn grant W09-032
Molecular pathology of feline oral squamous cell carcinoma
Investigators: Susan M. LaRue, E.J. Ehrhart
Colorado State University
Oral squamous cell carcinoma (OSCC) is a devastating disease in cats and accounts for approximately 10% of all feline tumors. The goal of the study’s investigators was to establish protocols for molecular biomarkers and to characterize the nature of this tumor so a better treatment protocol could be developed in the future.
They first developed protocols for immune staining of tissues and antibodies against three different biological markers.
One important detail learned was that sample processing is one of the most important factors affecting immunoreactivity of feline tissues. Due to this important finding, immunohistochemical techniques will be used only in formalin-fixed and paraffin-embedded tissues that do not undergo bone decalcification. The study results also noted that cats with high epidermal growth factor receptor (EGFR) expression had a tendency toward a shorter overall survival. This may suggest a possible usefulness for anti-EGFR therapy in future studies.
Finally, there was statistically significant correlation between one biomarker score, Ki67, and another marker, mitotic indexes. This relationship has not been reported previously in feline OSCC and suggests that these particular cancer cells with Ki67 can keep proliferating without going into a rest or dying phase. Such a result could go a long way to explaining the impression that feline OSCC is a fast-growing cancer. [VT]