Oral cancer is common, representing 10% of all tumors in cats. Squamous cell carcinoma is the most common of them, comprising approximately 65% of all oral cancers. Because of its location (tongue, mandible, or maxilla) and aggressiveness, oral SCC usually leads to loss of appetite, pain, and overall dramatic decrease in quality of life. Despite treatment, most cats will die from progression of their disease, and survival beyond a few months is not commonly seen. New therapies must be investigated in order to improve quality of life and survival rates of cats affected by this tumor. Two of these new therapies are retinoids and interferon. Retinoids, such as isotretinoin, are synthetic derivatives of vitamin A and have been successfully used against many different cancers in people. When combined with interferon (an immunostimulant and growth- inhibiting drug), synergistic effects have been seen in a number of human cancers. Side effects of either drug or their combination are uncommon and are usually manageable. This study will evaluate the effects of these drugs in SCC cell cultures, and intends to answer two main questions: does isotretinoin have an effect against oral SCC, and does this effect increase by combining it with interferon? The long-term goal of the study is to provide the basis for a new, safe, and efficient modality of treatment for cats affected by this dreadful disease.