Monocytic and myelo-monocytic (French-American-British classification M4/M5 subtypes) AML cells, but not cells from myeloblastic (FAB class M2) or immature (FAB class M1) AML, produce ROS via the NADPH oxidase component gp91phox, and trigger extensive apoptosis of NK cells via a poly-[ADPribose] polymerase-1 dependent pathway, together with a down-regulation of NKp46/NCR1. Here, FMO5 is linked to acute myeloid leukemia.