CYBB and leukemia: To address the role of NOX2, which is the dominant source of enzymatically derived ROS in normal and leukemic myeloid cells [25–28], in KRAS-driven leukemia we utilized double transgenic LSL-KrasG12D × Mx1-Cre mice where hematopoiesis was biased toward the NOX2+ granulocyte/monocyte linage.