PECAM1 and acute myeloid leukemia: CD90+ and CD10+ cells per high power field (HPF, 1000fold magnification, 2 replicates each) were also significantly higher in AML samples (Fig. 1B: CD90+: 19.0 vs. 3.5, p < 0.01, CD10+: 39.0 vs. 18.6, p < 0.05).There was no significant difference in CD31+ cells (4.2 vs. 4.2, p = 0.19, Fig. 1A and B), a marker for endothelial cells, which are also positive for CD90.