SsD exhibits anti-proliferation activity and promotes myeloid differentiation and apoptosis. (A) CCK-8 assays in SsD-treated AML cells after 48 h of treatment. (B) Colony-forming assays in NB4, Kas-1, MV4-11, and U937 cells, treated with different concentrations of SsD. Images show representative plates and (D) clones. (C) Graphs showing the colonies numbers from 3 independent experiments and (E) quantification of clone sizes from 10 clones. Data are the mean ± SD; *P < 0.05, **P < 0.01, ***P < 0.001. (F-G) Determination of the effect of SsD on cell-cycle arrest and apoptosis using FACS based on PI staining in NB4 cells after 48 h of treatment.