Analysis of different endothelial subpopulations revealed that in normal BM, CD31+Sca-1high ECs exhibit lower ROS and NO levels than CD31+Sca-1low ECs (Figure 5I), and AML engraftment caused an increase in both ROS and NO levels in the CD31+Sca-1high population (Figure 5J). The gene discussed is PECAM1; the disease is acute myeloid leukemia.