Effect of ND-09 treatment on cell apoptosis. The proportion of apoptotic cells was determined by double staining with Annexin V/FITC and PI in (A) K562, (B) JURKAT, and (C) HUT78 cells after treatment with ND-09 (0, 1.56, 3.12, and 6.25 µM). (D) Effect of ND-09 on mitochondrial membrane potential (Δψm). Δψm was assessed through flow cytometry following treatment of K562 cells with ND-09 (0, 1.56, 3.12, and 6.25 µΜ) for 48 h. (E) Quantitative analysis of flow cytometry data. (F) Effects of ND-09 on apoptosis-related protein expression in K562 cells. All results were quantified by densitometric analysis of the bands and were normalized to GAPDH (internal control). Samples were derived from the same experiment, and blots were processed in parallel. Values represent the average of three independent experiments. Data are presented as mean ± SEM (n=3). *P<0.05, **P<0.01 compared to the untreated control group.