中文摘要：

目的研究苯代谢产物1,2,4-苯三醇对K562细胞的增殖和分化的影响。方法应用台盼蓝染色排除法计数活细胞数,应用碘化丙啶（PI）染色结合流式细胞术分析细胞周期分布情况,应用PI/FITC-annexin V双染结合流式细胞术分析细胞凋亡情况,联苯胺染色法计数分析K562细胞红系分化情况。结果1,2,4-苯三醇（0.025～0.4 mmol/L）处理24 h对K562细胞产生浓度依赖性的增殖抑制。0.2 mmol/L的1,2,4-苯三醇作用24 h后,K562细胞G0/G1期细胞比例显著下降,S期和G2/M期细胞比例显著升高,细胞出现明显的细胞凋亡。用0.005 mmol/L浓度的1,2,4-苯三醇预处理24h的K562细胞经氯化高铁血红素诱导24、48和72 h的红细胞分化率分别是21.57%、40.62%和46.60%,均显著低于对照细胞相应时间点的红细胞分化率。结论在本试验条件下,苯代谢物1,2,4-苯三醇在一定的浓度范围内对K562细胞表现出浓度依赖性的增殖抑制作用,这种增殖抑制作用可能是通过细胞周期改变进而引起细胞凋亡来实现的,而在无细胞毒性的低浓度下1,2,4-苯三醇就可明显抑制K562细胞的红系分化,1,2,4-苯三醇的凋亡诱导作用和分化抑制作用可能在苯血液毒性机制方面有重要意义。

英文摘要：

Objective The impact of benzene metabolite 1,2,4-benzenetriol on proliferation and erythroid differentiation in K562 cells was observed.Methods Cell viability was detected using trypan blue exclusion assay.Propidium iodide staining and flow cytometry analysis were conducted to analyze the cell cycle.Apoptosis was measured by annexin V/propidium iodide staining and flow cytometry.The percentage of cells containing hemoglobin was estimated by staining with benzidine.Results The treatment of 1,2,4-benzenetriol（0.025～0.4 mmol/L） for 24h resulted in a concentration-independent inhibition on cell proliferation in K562 cells.The treatment with 1,2,4-benzenetriol at 0.2 mmol/L for 24h induced an accumulation at S and G2/M phases concomitant with a decrease at G0/G1 phases in K562 cells.The same treatment induced apoptosis in K562 cells with an early apoptotic percentage of 17.93% and a late death percentage of 22.80%.When K562 cells pretreated with 1,2,4-benzenetriol at 0.005 mmol/L for 24 were further treated with hemin to induce erythroid differentiation for 24 h,48 h or 72 h,the hemoglobin-positive percentages in K562 cells at each time point were 21.57%,40.62% and 46.60%,respectively.But the hemoglobin-positive percentage in control K562 cells was 26.23%,48.79% and 53.94%,respectively.Conclusion 1,2,4-benzenetriol inhibited the growth of K562 cell through inducing apoptosis and changing cell cycle,this benzene metabolite also inhibited erythroid differentiation at the non-cytotoxic concentration,which might played an important role in the mechanism of benzene-induced hematotoxicity.