Adipose tissue attracts and protects acute lymphoblastic leukemia cells from chemotherapy

Obesity is associated with an increased risk of acute lymphoblastic leukemia (ALL) relapse. Using mouse and cell co-culture models, we investigated whether adipose tissue attracts ALL to a protective microenvironment. Syngeneically implanted ALL cells migrated into adipose tissue within ten days. In vitro, murine ALL cells migrated towards adipose tissue explants and 3T3-L1 adipocytes. Human and mouse ALL cells migrated toward adipocyte conditioned media, which was mediated by SDF-1 alpha. In addition, adipose tissue explants protected ALL cells against daunorubicin and vincristine. Our findings suggest that ALL migration into adipose tissue could contribute to drug resistance and potentially relapse. (C) 2012 Elsevier Ltd. All rights reserved.