Activation of p53 and inhibition of XIAP synergistically promote apoptosis in p53 wt acute myeloid leukemia (AML) cells. OCI-AML3 and Molm13 cells were treated with nutlin-3a, 1396-11, or both. Cell death was determined at 24 hours. N3a indicates nutlin-3a; 1396, 1396-11.