1. Laboratoire de Pharmacologie Antitumorale Moléculaire du Centre Oscar Lambret et INSERM U-124, Place de Verdun, 59045 Lille, France, Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QJ, U.K., and Department of Biochemistry, University of Mississippi Medical Center, 2500 North State Street, Jackson, Mississippi 39216-4505