CASP3 and leukemia: 753B treatment reduced senescence markers and SASP cytokine expression (IL-6, IL-8, IL-1β, CCR5), indicating clearance senescent cells. Apoptosis induction was verified by Annexin-V/DAPI staining and cleaved caspase-3/PARP western blotting. Increased BCL-XL expression in senescent cells and its degradation by 753B confirmed senolytic elimination of dormant leukemia cells, validated in vitro and in vivo.