【摘要】 目的研究K562白血病细胞在全反式维甲酸(ATRA)诱导分化过程中线粒体铁蛋白(MtF)、运铁蛋白受体1(TfR1)和铁蛋白(Fn)mRNA表达水平的变化情况,探讨MtF在白血病细胞增殖和铁代谢方面的作用。方法K562细胞加入ATRA(终浓度1μmol/L)中诱导培养,分别于第1、3、5 d收集细胞,分别进行:①瑞士染色观察各时间点的细胞形态;流式细胞学检测细胞表面分化抗原CD13的表达;②Trizol法提取各时间点细胞的RNA,通过半定量RT-PCR方法检测各时点MtF、TfR1和Fn基因的表达水平。同时设未用ATRA诱导培养的K562细胞为对照组。结果1μmol/L的ATRA可诱导K562细胞向粒系细胞分化,诱导培养第5 d,细胞表面CD13的表达水平增加,诱导分化率为21.2%,与对照组比较,差异有统计学意义(P<0.05)。诱导分化前K562细胞即有MtFmRNA表达,但随细胞诱导时间的延长,MtF和TfR1 mRNA表达呈下降趋势,诱导分化第5 d的表达水平分别为诱导分化前的86.5%和79.2%;而FnmRNA的表达呈上调趋势,诱导分化第5 d表达水平为诱导分化前的1.21倍。结论ATRA诱导K562细胞向粒系细胞分化过程中,MtF和TfR1 mRNA表达下调,而FnmRNA表达上调,这种协调变化有助于降低细胞通过TfR1介导的铁摄取,从而抑制或影响细胞增殖潜能。更多还原

【Abstract】 Objective To investigate the expression of MtF, transferrin receptor 1(TfR1) and ferritin(Fn) mRNAs in K562 leukemic cells during ATRA-induced cell differentiation and to explore the interrelationship between the expression levels of these iron metabolism-related molecules.Methods K562 cells cultured with or without ATRA(1 μmol/L) were collected at 24,72 and 120 hours respectively.Cell differentiation toward granulocyte lineage was confirmed by microscopic study(Wright’s staining) and flowcytometry.Expression levels of MtF,TfR1 and Fn were evaluated with semiquantitative RT-PCR,while K562 cells cultured without ATRA as control.Results Over 21.2% of K562 cells demonstrated features of granulocyte, and the expression of CD13 on cell surface increased significantly at day 5 with ATRA treatment(P<0.05,compared with control).K562 cells could express a certain level of MtF before ATRA-induced differentiation.With increase of ATRA-induced cell differentiation,MtF mRNA expressions were downregulated progressively.After 5 days of induced cell differentiation,expression levels of MtF and TfR1 mRNA were just 86.5% and 79.2% of that before ATRA treatment.While Fn mRNA expression increased to 1.21 folds of that before ATRA treatment.Conclusion MtF expression is downregulated during ATRA-induced K562 cell differentiation,with concomitant downregulation of TfR1 and upregulation of Fn.The coordinated expression regulation of these key iron metabolism-related molecules during cell differentiation may in turn inhibit TfR1-mediated iron uptake via endocytosis and thus adversely affect cell proliferation potential.更多还原