Objective To detect the expression of cytokines by acute promyelocytic leukemia (APL) cells before and after exposure to arsenic trioxide.Methods Diagnoses were performed according to the FAB cytological classification criteria and cytogenetic criteria. Bone marrow or blood samples from APL patients were collected in heparinized tubes,then primary APL cells were separated by traditional Ficoll-Hypaque density centrifugation and purified after adherence to plastic surfaces. IL-1β, IL-6, IL-8, TNFα and G-CSF levels in the leukemia cell culture supernatants were detected by ELISA. At the same time, nitro blue tetrazolium (NBT) reduction test was used to detect the differentiation of APL cells.Results After 96 hours exposure to arsenic trioxide, 10-6 mol/L in vitro or 10 mg/d in vivo, APL cells showed a significant increase of IL-1β ( P < 0. 05) and G-CSF ( P < 0. 05) production, and a significant decrease of IL-6 (P<0. 05) and IL-8 (P<0. 05). However, there was no obvious variation of TNFα when compare Objective To detect the expression of cytokines by acute promyelocytic leukemia (APL) cells before and after exposure to arsenic trioxide. Methods Diagnoses were performed according to the FAB cytological classification criteria and cytogenetic criteria. Bone marrow or blood samples from APL patients were collected in heparinized tubes, then primary APL cells were separated by traditional Ficoll-Hypaque density centrifugation and purified after adherence to plastic surfaces. IL-1β, IL-6, IL-8, TNFα and G-CSF levels in the leukemia cell culture supernatants were detected by ELISA. At the same time, nitro blue tetrazolium (NBT) reduction test was used to detect the differentiation of APL cells. Results After 96 hours exposure to arsenic trioxide, 10-6 mol / L in vitro or 10 mg / d in vivo, APL cells showed a significant increase of IL-1β (P <0.05) and G-CSF (P <0.05) production, and a significant decrease of IL- P <0. 05). However, there was no obvious variation of TNFα when compare