Research — 2009 Studies

Principal investigator: Dr. Tomas Martin-Jimenez
As companion animals live longer, cancer has become one of the major causes of death. The goal of chemotherapy is to maximize the therapeutic response while minimizing toxic effects. Unfortunately, determining the appropriate dose that each dog needs is difficult. Factors such as age, weight and kidney function influence an animal's response to chemotherapy. This study will discover how these factors affect a dog's response to a chemotherapy commonly used to treat osteosarcomas and carcinomas. They will use this information to develop a dose calculator that would help veterinarians tailor the dose to the specific needs of individual dogs. This would provide more effective treatment and alleviate unwanted side effects.

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Principal investigator: Dr. Stuart C. Helfand
Hemangiosarcoma remains one of the deadliest canine cancers. Despite treatments such as chemotherapy, immunotherapy and surgery, dogs rarely live beyond six months after diagnosis. New approaches are needed to improve the survival time of dogs afflicted with this devastating disease. This study will expand on the research team's previous research into a novel class of drugs called tyrosine kinase inhibitors that may have the potential to control the growth of hemangiosarcoma. The results will help to clarify abnormalities that contribute to hemangiosarcoma proliferation and may ultimately lead to new treatment options for this aggressive cancer.

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Principal investigator: Dr. Lara K Maxwell
Vinca alkaloids are chemotherapy drugs used to treat mast cell tumors, a common cancer in dogs. Unfortunately, these drugs work well in less than 50 percent of treated dogs. This low effectiveness may be because the standard drug doses are too low for many dogs. If scientists had a better understanding of the factors that affect how these drugs are cleared from a dog's system, they could make better dosing recommendations based on a dog's size. This study will develop improved methods of individualizing effective doses of vinca alkaloids, allowing more dogs to respond favorably to therapy.

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Principal investigator: Dr. Anne C. Avery
Canine chronic lymphocytic leukemia is a cancer of the lymphocytes that affects most dog breeds and is especially common in golden retrievers. The disease is often an incidental finding in an otherwise healthy older dog. In some cases, dogs can live for several years without treatment, but in others the dog may die within months of diagnosis. Identifying genetic markers that are able to differentiate between a leukemia with a good prognosis and one with a poor prognosis would help veterinarians better predict a patient's survival and help them make more knowledgeable treatment decisions.

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Principal investigator: Dr. Jane E. Sykes
Lymphoma is one of the most common cancers of dogs, but its cause is unknown. Its development appears to be linked to genetics as well as environmental and infectious disease factors. Previous work conducted by this research team suggests a link between lymphoma and canine hemoplasma infection. Hemoplasmas are bacteria that adhere to red blood cells and can persist in the dog's blood without causing signs of disease. This study hopes to determine whether dogs with untreated lymphoma have a higher prevalence of hemoplasma infection than dogs with untreated mast cell tumors and sarcomas. The findings may provide important information into one of the causes of lymphoma.

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Principal investigator: Dr. Nikolaos G. Dervisis
Canine histiocytic sarcoma is an aggressive form of cancer that is almost always fatal. The disease affects primarily Bernese mountain dogs, flat-coated retrievers and rottweilers, but others are predisposed as well. Despite rigorous efforts to identify genetic abnormalities underlying this disease, few treatment advances have been made. The researchers will focus on gene expression patterns that are associated with this cancer's resistance to chemotherapy. They intend to develop a practical test that can be used to guide future drug development for the treatment of canine histiocytic sarcoma.

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Principal investigator: Dr. Margaret C. McEntee
Cancer has increasingly become an important cause of illness and death in companion animals, but limited resources are available for early testing of new treatments. As a result, little clinical data are available to confirm efficacy of these treatments in cats. In addition, some of the most effective chemotherapeutic agents can't be used in cats due to their administration requirements or potential to cause side effects. Docetaxel is one of the most effective human anti-cancer drugs, but because it causes adverse reactions in cats when given intravenously, it hasn't been thoroughly evaluated. Docetaxel combined with cyclosporine dramatically improves the absorption of oral docetaxel from the gastrointestinal tract and avoids the adverse reactions. A previously funded study determined the best dose of oral docetaxel. This study will now evaluate the effectiveness of oral docetaxel to treat cats with epithelial cancer.

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Principal investigator: Dr. Chung S. Park
Cats have the highest incidence for lymphoma of any pet animal. Although nutrition is known to play an important role in cancer risk and tumor behavior, few studies have looked at the use of nutrients in treating feline lymphoma. Lipotropes, which are a type of methyl nutrient, may be able to inhibit the growth of lymphoma cells. This study will investigate whether supplementing feline lymphoma cells with lipotropes will inhibit the growth of cancer in a cell culture. The findings could lead to new dietary and nutritional therapies for decreasing the incidence of feline lymphoma.

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