Fig. 6: In vivo analysis revealing direct targeting of APL primitive blasts (including stem-like cells) by ATRA and induction of their differentiation and maturation.

a UMAP plot showing the integration of APL BM cells (n = 39,415 cells) collected on Day 0 (red) and Day 2 after ATRA treatment (blue). b UMAP plots showing all defined cell populations of APL BM cells (n = 39,415 cells) collected on Day 0 and Day 2 after ATRA treatment. c Comparison of the percentages of six branches before (red) and after two days of ATRA treatment (blue). d Comparison of the percentages of the stem-like, Prog-like, S100^hiGMP-like, and GMP-like cells on Day 0 (red, n = 3 samples) and Day 2 after ATRA treatment (blue, n = 3 samples). The P-values were calculated using Student’s t-test. A one-sided P-value was calculated. In the boxplot, a black line within the box marks the median. The bottom and top of the box are located at the 25^th and 75^th percentiles, respectively. e Comparison of the Primitive-to-Mature scores of APL blasts on Day 0 (red, n = 13,966 cells) and Day 2 after ATRA treatment (blue, n = 10,852 cells). f Comparison of APL stem-like cell percentages (left panel) and stemness scores (right panel) on Day 0 (in red, n = 7 samples), Day 2 (in blue, n = 7 samples treated with ATRA alone), and Day 5 (in orange, n = 5 samples treated with ATRA + ATO). Notably, within the boxplot shown in (e and f), a black line marks the median, and the bottom and top of the box are located at the 25^th and 75^th percentiles, respectively. The bars represent values more than 1.5 times the interquartile range from the border of each box. The P-values were calculated using the Wilcoxon rank-sum test. Two-sided P-values were calculated. g Heatmap showing the normalized expression of stemness CD markers and TFs in APL stem-like cells, Prog-like, S100^hiGMP-like, and GMP-like clusters on Day 0 (red) and Day 2 after ATRA therapy (blue). h Heatmap showing the normalized expression of differentiation markers and hematopoietic TFs in APL stem-like cells, Prog-like, S100^hiGMP-like, and GMP-like clusters on Day 0 (red) and Day 2 (blue) after ATRA therapy. i Heatmap illustrating the log₂(fold changes) (log₂FC) of gene expression levels for stemness-associated CD markers and TFs between APL samples on Day 0 and Day 2 (Day 2 vs. Day 0) in different APL patients. j Heatmap illustrating the log₂FC of gene expression levels for differentiation markers and hematopoietic TFs between APL samples on Day 0 and Day 2 (Day 2 vs. Day 0) in different APL patients. Gray represents patients alive after induction therapy, and black for patients with early death.