中文摘要：

背景与目的：蛋白激酶CK2是一种高度保守的第二信使非依赖性丝／苏氨酸蛋白激酶，它与人白血病关系密切，而米托蒽醌是一种临床常用的治疗急性白血病的特效药。本实验观察米托葸醌对重组人蛋白激酶CK2全酶活性的影响．并将其作用于人早幼粒细胞白血病细胞HL-60，探讨它对HL-60细胞的影响。方法：体外将CK2α和β亚基重组构成CK2全酶，然后加入不同浓度的米托蒽醌与含有[γ-^32P]标记ATP的反应混合液处理，CK2活性通过测定转移到CK2底物上的[^32P]放射活度来检测；然后采用台盼蓝拒染法观察米托蒽醌对HL-60细胞毒性，流式细胞术检测药物对细胞周期影响的情况，流式细胞术和琼脂糖凝胶电泳观察药物处理后细胞凋亡的情况，最后通过使用CK2特异的多肽底物检测药物对细胞内CK2活性的影响。结果：米托蒽醌对重组人CK2全酶具有较强的抑制作用，IC50为0．66umol／L；进一步分析它与ATP呈竞争性抑制CK2的活性，抑制常数K；值为0．25umol／L：与酪蛋白呈以非竞争性为主的混合性抑制CK2的活性，抑制常数K值为0．66umol／L。它对HL-60细胞有很强的细胞毒性，并能诱导HL-60细胞发生凋亡．但对细胞内CK2活性无明显影响。结论：米托蒽醌是蛋白激酶CK2的有效抑制剂，它能引起HL-60细胞凋亡，但其凋亡机制可能与胞内CK2活性无关。

英文摘要：

BACKGROUND ＆ OBJECTIVE： Protein kinase CK2, a highly conserved protein serine/threonine kinase that is ubiquitously distributed in eukaryotes, has a close relationship with human leukemia. Mitoxantrone is an effective drug used for acute leukemias. This study was to observe the effects of mitoxantrone on the activity of recombinant holoenzyme of human protein kinase CK2 and proliferation in human leukemia cell line HL-60. METHODS： The CK2 holoenzyme composed of α＇ and β subunits was recombinanted in vitro. Subsequently, CK2 was treated with mitoxantrone at various concentrations, followed by addition of reacting liquid containing [γ- ^32P] ATP. CK2 activity was measured by detecting the radioactivity of ^32P transferred onto the substrates of CK2. The effect of mitoxantrone on the proliferation of HL-60 cells was detected by the trypan blue dye exclusion assay; the changes in the cell cycle were analyzed by flow cytometry （FCM）; apoptosis was analyzed by FCM and DNA agarose gel electrophoresis; effects of the drugs on the intrinsic CK2 activity were measured by a specific CK2 peptide substrate. RESULTS： Mitoxantrone strongly inhibited the holoenzyme activity of recombinant human protein kinase CK2 （IC50=0.66 umol/L）. The inhibition of CKZ by mitoxantrone was competitive with respect to ATP （Ki 0.25 umol/L） and mostly noncompetitive with respect to casein （Ki 0.66 umol/L）. Mitoxantrone exerted strong cytotoxicity to HL-60 cells. When treated with 0.1 umol/L mitoxantrone for 12 h, the apoptotic rate of HL-60 cells was 9.3%. Mitoxantrone did not affect intracellular CK2 activity. CONCLUSIONS： Mitoxantrone is a strong inhibitor of recombinant human protein kinase CK2 in vitro. Apoptosis induced by mitoxantrone in HL-60 cells has no correlation to intraceilular CK2 activity.