Increased number of autophagosomes and decreased GFP-LC3 expression were observed in PB leukemic cells. (A) Expression of LC3A-I and LC3A-II in BM and PB from GFP-LC3 MLL-ENL leukemic mice. (B) Relative signal intensities of LC3A-II in BM and PB from GFP-LC3 MLL-ENL leukemic mice are shown. Values were normalized to the intensity of LC3A-II/β-actin from BM samples (n = 5, mean ± SD). (C) Representative electron micrograph of c-Kit⁻CD11b⁺ cells from BM or PB of MLL-ENL leukemic mice. The grids were observed by a transmission electron microscope (JEM-1400Plus; JEOL Ltd., Tokyo, Japan). Digital images were taken with a CCD camera (VELETA; Olympus Soft Imaging Solutions, Germany). White arrows indicate autophagosomes. (D) Frequency distribution of detectable autophagosomes per cell from electron micrograph analysis. The number of autophagosomes in 100 cells, derived from 2 independent mice, was counted. The P value was calculated with the Wilcoxon rank sum test. Representative histogram and collective data (n = 8) of GFP-LC3 expression in c-Kit⁻CD11b⁺ (E) or c-Kit⁺CD11b⁺ (F) cells in BM or PB from GFP-LC3 MLL-ENL leukemic mice. Geometric MFIs were plotted. P values were calculated by a Student paired t test. *P < .05; **P < .01. All results are pooled data from at least 3 independent experiments with 1 to 3 animals per experiment.