α-干扰素联合脂多糖对白血病细胞株U937细胞周期的影响及其机制研究

摘要

Objective To explore the effects of INF - α combinated by lipopolysaccharide on the proliferation, apop-tosis, and cell cycle of U937 acute myelogenous leukemia ( AML ) cells and its possible mechanisms in vitro. Methods MTT assay was applied to determine cell proliferation, AnnexinV/PI double labeling was used in the flow cytometry ( FCM ) method to analyze cell apoptosis and cell cycle, Western blotting were employed to quantify the expression of cyclinA2 and cyclinDl protein. Results INF - α and/or lipopolysaccharide inhibited leukemic proliferation, induced cell apoptosis and caused cell cycle arrest in G1 phase ( P ＜0. 05 ). INF - α - LPS combination exhibited better effects in inhibiting leukemic proliferation, promoting cells apoptosis, and inducing cell cycle arrest in G1 phase compared with INF - α or LPS used alone ( P ＜0. 05 ). INF - α - LPS combination significantly decreased cyclinA2 protein expression and increased cyclinDl protein expression in U937in comparison with INF - α or LPS used alone. Conclusion Synergistic effects of INF - α and LPS exist in inhibiting leukemic proliferation , inducing cell apoptosis and causing Gl phase cell cycle arrest in U937 cell line, which were partially explained by the re-grulation of cyclinA2 and CyclinDl protein expression.%目的 探讨α-干扰素联合脂多糖在体外对髓系白血病 (acute myelogenous leukemia,AML) 细胞U937细胞增殖、凋亡及细胞周期的影响及其机制.方法 四甲基偶氮唑蓝法(MTT法)检测细胞增殖;Annexin V FITC/PI双染色法流式细胞仪检测细胞凋亡率;流式细胞仪检测细胞周期,Western blotting检测 cyclinA2和cyclinD1蛋白质表达.结果 α-干扰素和(或)脂多糖组较对照组能显著地抑制U937细胞的增殖、增加细胞的凋亡率和G1期细胞比例(P＜0.05＝;α-干扰素联合脂多糖组较单用α-干扰素、脂多糖组能显著抑制U937细胞增殖、增加细胞凋亡率和G1期细胞比例(P＜0.05＝,能够显著下调CyclinA2蛋白质表达、上调CyclinD1蛋白质表达 (P＜0.05).结论 α-干扰素与脂多糖对U937细胞的增殖抑制、细胞凋亡和G1期细胞的比例有协同增强作用,其机制可能与细胞周期素CyclinA2、CyclinD1蛋白的调节有关.