槲皮素对人早幼粒白血病细胞RNA聚合酶活性和细胞周期的影响

The effect of quercetin on RNA polymerases and cell cycle in human leukemia HL-60 cell

本文旨在探讨槲皮素对人早幼白血病细胞（HL－60）RNA聚合酶活性和细胞周期的影响及其相互关系。分别用4、20和100μmol／L槲皮素处理培养的HL-60X细胞2天或用20μmol／L槲皮素处理0－5天。应用流式细胞仪进行细胞周期分析，并通过体外核转录实验测定总RNA聚合酶活性和RNA聚合酶Ⅱ活性。结果表明，槲皮素处理HL－60细胞后，体外核转录活性降低，总RNA聚合酶活性尤其是RNA聚合酶Ⅱ活性受抑制，并呈时间和剂量依赖关系；细胞周期中G1期细胞增加，并与作用时间和剂量呈依赖关系，提示槲皮素阻断HL-60细胞周期于G1期；结果分析还表明，槲皮素处理的HL－60细胞，其总RNA聚合酶活性尤其是RNA聚合酶Ⅱ活性受抑制程度与G1期细胞所占百分比增加程度呈明显的相关性。提示槲皮素抑制HL－60细胞体外核转录活性尤其抑制RNA聚合酶Ⅱ活性，可能是槲皮素阻断HL-60细胞周期于G1期的影响因素之一。

TO study foe effect and the relationship of queroetin on RNA polymerases and cell cycle in Human leukemia HL-60 cells. Treating of HL-60 cells with 4, 20 and 100μmol/L quercetin for 2 days,or wilh 20μmol/L for 1~5 days, the cell cycle were analyzed with flow cytometer. And total RNA polymerases activity and RNA polymerase Ⅱactivity were measured in isolated HL-60 nuclei by nuclear transcription in vitro. After treatment of HL-60 cells with quercetin, total RNA polymerase ac- tivity,especially RAN polymerase Ⅱactivity showed inhibitory effects in time-and dose-dependent manner.The cells at G1, phase increased at the same way. This phenomena revealed that quercetin could arrest cell cycle progression of HL-60 at G1 phase. These observation also suggest that quercetin treatment of HL-60 cells gave the inhibitory effectS of total RNA polylnerases activity and especially RNA polymerase Ⅱ activity, is related to the cell increase at G1 phase. It may be one of reason that queroetin could block in G1 phase of HL-60 cell cycle because of its inhibitory effects on nuclear transcription in vtro, especially on RNA polymelase Ⅱ.