Cachexia is the dramatic weight loss seen in patients with chronic illness including type I diabetes, multiple sclerosis, HIV, cancer, and in aging individuals with failure to thrive syndrome. In all patients with cachexia the result is severe skeletal muscle loss and immobility. In cancer patients, cachexia also leads to an inability to respond effectively to therapy resulting in poor prognosis. Recently, the Davies laboratory has identified a factor that inhibits both the incidence and severity of cachexia in cancer, and in type I diabetes. By better understanding the way this factor works, Dr. Davies' laboratory hopes to identify information that might be used to develop new therapeutic strategies and drugs to treat cachexia in cancer as well as type I diabetic patients. The long-term goal is to increase both survival and quality of life for patients with chronic illnesses.