Evaluating Arsenic Compounds on Leukemia

Human NB4 leukemia cells were purchased from SXBIO Biotech (Shanghai, China). Human primary APL cells were separated from the bone marrow of four primary APL patients acquired from DrumTower Hospital (Nanjing, China) by Ficoll-Hypaque density centrifugation as reported in the previously published article [28 (link)]. Written informed consent was obtained from individual subjects. For this case we did not seek approval of the Ethics Committee of Drum Tower Hospital and did not obtain a waiver from the Ethics Committee because the bone marrow was part of that acquired for clinical diagnosis and destroyed after this experiment. NB4 cells were cultured in RPMI-1640 (KeyGEN Biotech, China) with 10% fetal bovine serum (FBS) at 37°C under a 5% CO₂ atmosphere. The fresh primary APL cells were cultured in RPMI-1640 with 15% FBS. Trypan blue exclusion was used to determine viability of NB4 and primary APL cells after 48 h and 96 h of culture [28 (link)]. The effects of As₄S₄ and As³⁺ on cell growth were determined using the WST-1 cell proliferation assay kit (KeyGEN Biotech, China). In brief, 4×10⁴ cells/ml were seeded into a 96-well culture plate and treated with various concentrations of As₄S₄, As³⁺, or their combination for 48 h. Untreated cells served as controls [28 (link),29 (link)].