Research — 2008 Studies

Principal Investigator: Dr. Laura J. Rush
Lymphoma is one of the most common cancers in dogs. Although some breeds have higher incidence — including boxers, bull mastiffs, basset hounds, bulldogs, golden retrievers and Labradors — all dogs can develop the disease. Dogs with lymphoma usually respond well to chemotherapy, but most will eventually relapse and die of their disease within a year after chemotherapy. This may be due to residual disease that remains in the dog’s body after treatment but can’t be detected. In a previous MAF-funded study, Dr. Rush and her team showed that a simple blood test measuring plasma DNA levels may predict which dogs will have a shorter remission. This study will determine whether this test can detect relapse before clinical signs appear and whether the blood levels measured by the test can identify if the patient has disease remaining after completion of chemotherapy.

---

Principal investigator: Kerstin Lindblad-Toh, PhD
Mast cell tumors (MCT) are the most common skin tumors in dogs. Survival rates are dependent upon the tumor grade. While dogs with grade 1 tumors often experience long-term survival, those with grade 3 tumors usual die within six months. This cancer has a particularly high occurrence in certain breeds, which suggests a significant genetic component. This study will use a new approach to identify genes that contribute to an increased risk of developing mast cell cancer in golden retrievers and related breeds. Identifying these genes will help scientists rapidly develop genetic tests that would indicated a predisposition to this cancer and would help develop therapeutic strategies based on tumor grade.

---

Principal investigator: Dr. Susan L. Kraft
Lymphoma is one of the most common canine cancers. Despite a good initial response to chemotherapy, affected dogs typically relapse and survive less than two years. The investigators are studying the metabolism of canine lymphoma to help identify tumor biomarkers. To do so, they will use a technology called nuclear magnetic resonance spectroscopy. This technology led to the discovery of human tumor biomarkers that are now used for improved diagnostic specificity, prognosis, assessment of treatment response and to develop new therapeutic targets. To date, this approach hasn’t been used to study cancers in pets. Identification of these biomarkers will help predict whether a dog’s tumor will respond well to chemotherapy, how long the cancer will stay in remission, and in the future could help develop new treatments for this deadly disease.

---

Principal investigator: Rachael Thomas, Ph.D.
Feline injection-site sarcomas associated with vaccine administration afflict as many as 22,000 cats a year in the United States. Although these tumors often resemble other tumors not related to injection, they are typically devastating and require much more aggressive treatment than conventional sarcomas. Diagnosis can be hindered by an inability to accurately distinguish between injection-site sarcomas and those that aren’t related to injection. This study will use new genetic tools to establish whether recurrent chromosome abnormalities exist in feline sarcomas. They hope to reveal subtype-specific genomic features found in injection-site sarcomas that would aid in diagnosis and treatment selection, and ultimately improve treatment and survival rates.

---

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 is available to confirm efficacy of these treatments in cats. In addition, some of the most effective chemotherapeutic agents aren’t usable in cats due to their administration requirements or potential to cause toxicity. Docetaxel is one of the most effective human anticancer 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 GI 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 docetaxel in treatment of cats with epithelial cancer.

---

Principal investigator: Dr. Steven E. Suter
Canine lymphoma is one of the most common tumors in dogs. Though initially dogs respond well to treatment, the disease has a dismal overall cure rate of less than 10 percent. Dogs usually die due to a recurrence of the disease that is resistant to conventional chemotherapeutic drugs. Using a new technology called epigenomic research, researchers hope to begin to understand how two resistance genes are regulated. This project will shed new light on the development of acquired resistance, which is the main reason that dogs with lymphoma cannot be cured.

---

Principal investigator: Dr. Tomás Martin-Jiménez
As companion animals live longer, cancer has become one the major causes of death. Therapy with anticancer drugs remains one of the mainstays of cancer treatment in dogs. 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. The goal of this study is to better understand how these factors affect a dog’s response to carboplatin chemotherapy, commonly used to treat osteosarcomas and carcinomas, and to use this information to develop a dose calculator that would allow veterinarians to tailor the dose to the specific needs of individual dogs. This would provide more effective treatment and alleviate unwanted side effects.

---