Obesity hinders treatment in pediatric leukemia

Obesity may contribute to chemotherapy resistance and increasing relapse rates among children with leukemia, an animal study in Cancer Research (online, September 22, 2009) suggests.

Steven D. Mittelman, MD, PhD, and colleagues developed a mouse model of obesity and leukemia for which they cultured fat and leukemia cells together, and treated the leukemia cells with traditional chemotherapy drugs used in children: vincristine, nilotinib (Tasigna), daunorubicin, and dexamethasone.

According to the results, obese mice with leukemia had higher relapse rates than lean mice after treatment with the first-line chemotherapeutic agent vincristine. The chemotherapy treatments all worked less effectively in culture when fat cells were nearby. When the mice relapsed from the leukemia, the researchers found leukemia "hiding out" in the fat tissue during chemotherapy, said Dr. Mittelman's group, based at Children's Hospital Los Angeles and the Keck School of Medicine at the University of Southern California.