Reports on two Winn-funded studies:
Squamous cell carcinoma (SCC) of the oral cavity is one of the most common cancers of cats, and often has a poor outcome. This cancer develops in the jaw, gum, and under the tongue of cats. Oral SCC aggressively invades local tissue, causes bone destruction and spreads to other parts of the body. The options for the treatment of oral SCC are limited and less than 10% of cats survive one year from the time of diagnosis. In most cases, the treatment goals are to palliate pain until the oral tumor has advanced to a stage where comfortable eating and breathing are not possible and euthanasia is chosen.
W10-045: New Staging Techniques and Evaluation of Therapies for Oral Squamous Cell Carcinomas, $15,000
Maria Cekanova, MS, RNDr, PhD, Alfred Legendre, DVM, MS, DACVIM, Amy LeBlanc, BS, DVM, University of Tennessee
Cyclooxygenase (COX) enzyme is important for inflammation and tumor growth. It has been shown that COX-2 inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), such as piroxicam, meloxicam, and celecoxib could be used for the detection of COX-2 in tumors. This study used new COX-2 inhibitors labeled with fluorescence or radio-tracers to detect oral SCC cells. In addition, the study assessed potential treatments in vitro with different COX-2 inhibitors alone or in combination with a tyrosine kinase inhibitor (TKI), masitinib, using cells from naturally occurring tumors. Masitinib inhibits epidermal growth factor receptor, which is also responsible for the growth of SCC. The study results showed that NSAIDs and mastinib did indeed lead to death of tumor cells in the laboratory. This drug combination must still be evaluated cats with oral SCC, but holds promise for an effective treatment. [MK]
W11-027: Cetuximab Targeting of Epidermal Growth Factor Receptor in Feline Oral Squamous Cell Carcinoma $15,000
Stuart C. Helfand, DVM, Professor, Krystal Claybrook, DVM, Oregon State University
This research project investigated the treatment of oral SCC with TKI drugs such as cetuximab. TKIs disrupt the cellular signalling network that drives cancer development. The researchers found that the targets of TKI drugs are activated in the feline tumors, indicating they may play a role in cancer development. Use of TKIs led to suppression of tumor growth in cell cultures in the laboratory. Combinations of more than one TKI drug led to more profound tumor suppression. While the treatment still requires testing in cats, this research has the potential to lead to an effective treatment for oral SCC. [MK]