For comparison, here is the original abstract as displayed by our tex-to-html converter. In this work we use an integrated computational/experimental approach to study the effects of the tyrosine kinase inhibitor Nilotinib and ionizing radiation on acute lymphoblastic leukemia (ALL) cells. We develop a mathematical model, parameterized via cell viability experiments under Nilotinib treatment and radiation exposure, to predict cellular response to combination therapy. We find that the combination of Nilotinib and radiation yields synergistic effects. Model-predicted cellular responses to new combinations are then validated with an independent set of experiments. Using this validated model, we study the structure of optimal radiation/Nilotinib dosing schedules.