Multiple effects of prinomastat on leukemic blasts in the BM. (A) Representative tilescan maximum projections of calvarium BM of PBS- and prinomastat-treated AML-burdened mice. Red: mTomato⁺ healthy hematopoietic cells; green: YFP⁺ AML cells; gray: bone collagen. Scale bar represents 500 µm. (B) Mean gray value quantification of YFP signal (AML) within the calvarium BM of vehicle- and prinomastat-treated leukemic mice. n = 3 per condition. (C) AML cells number in long bones (femur) and calvaria of vehicle/prinomastat-treated AML-burdened mice immediately post IVM (day 16). n = 5 mice per condition. (D) Percentage of AML blasts measured in the PB of vehicle- and prinomastat-treated mice throughout disease progression. n = 16 mice per group. (E) Number of AML cells in the BM at 2 days after prinomastat treatment (day 23). n = 5 mice/group. (F) The number of AML and (G) healthy cells in the long bones of vehicle- and prinomastat-treated leukemic mice measured 5 days after prinomastat treatment (day 26). Each dot represents 1 mouse. n = 20 vehicle-treated and 20 prinomastat-treated mice pooled from 3 independent experiments. (H) The proportion of proliferating (EdU⁺) and (I) apoptotic/dead (annexin V+) AML blasts in the BM of PBS- and prinomastat-treated mice. n = 4 and 5 mice per group, respectively. (J) AML spleen infiltration of vehicle- and prinomastat-treated AML-burdened mice. n = 12 PBS- and 12 prinomastat-treated mice. (K) Growth curve showing the effect of prinomastat on AML cells proliferation in vitro. Data pooled from 3 independent experiments. All data are mean ± SEM. *P < .05; ***P < .001; ****P < .0001; ns, not significant. P values are determined by Student t tests.