二乙酰二脱水卫矛醇诱导白血病HL-60细胞凋亡及其机理

目的研究二乙酰二脱水卫矛醇(DADAG)诱导人白血病HL-60细胞凋亡及其机理。方法MTT法观察DADAG的体外抗增殖作用;透射电镜、DNA梯形条带和流式细胞仪检测HL-60细胞凋亡;Western blotting法和caspase-3检测试剂盒分析DADAG诱导HL-60细胞凋亡与Bcl-2家族成员和caspase-3的关系。结果DADAG明显抑制HL-60细胞增殖和诱导细胞发生凋亡。8 μg·mL^-1 DADAG处理HL-60细胞不同时间后,Bcl-X_L蛋白水平呈时间依赖性地下降,而Bad蛋白水平上调。DADAG处理HL-60细胞24 h后,caspase-3酶活性达峰值。Caspase-3抑制剂z-DEVD.fmk可部分逆转DADAG诱导HL-60细胞凋亡的作用,而caspases广谱抑制剂z-VAD.fmk可完全逆转此作用。结论DADAG诱导HL-60细胞凋亡依赖caspase-3途径的激活,而caspase-3的激活可能与Bcl-2家族成员密切相关。     

二乙酰二脱水卫矛醇对白血病L1210细胞增殖的抑制作用

目的探讨二乙酰二脱水卫矛醇(diacetyldianhydrogalactitol,Dadag)对小鼠白血病细胞株L1210细胞的增殖抑制作用及其机制。方法采用MTT比色法、平板集落形成实验和Hoechst 33258荧光染色法,分析Dadag对L1210细胞的生长抑制和凋亡影响。结果Dadag对L1210细胞有浓度依赖性的细胞毒性作用,抑制肿瘤细胞集落形成,并可诱导L1210细胞发生凋亡。结论Dadag对白血病L1210细胞的增殖抑制作用与其诱导肿瘤细胞发生凋亡密切相关。     

Caspases家族成员促进DADAG诱导的人白血病HL—60细胞凋亡

目的:研究caspases家族成员在二乙酰二脱水卫矛醇(DADAG)诱导人白血病HL-60细胞凋亡中的作用.方法:MTT法观察DADAG的体外抗增殖作用;透射电镜、DNA梯形条带和流式细胞仪检测HL-60细胞凋亡;caspase-3检测试剂盒和Western blot法分析caspases家族成员.结果:DADAG明显抑制HL-60细胞增殖和诱导细胞凋亡.DADAG处理HL-60细胞24h后,caspase-3酶活性达峰值,同时聚腺苷二磷酸核糖聚合酶(PARP)、lamin B和DFF45蛋白开始出现断裂片段.Caspase-3抑制剂z-DEVD·fmk可部分逆转DADAG诱导的HL-60细胞凋亡,而caspases广谱抑制剂z-VAD·fmk可完全逆转此作用.结论:Caspases在DADAG诱导HL-60细胞凋亡中起重要作用,它们通过酶解底物PARP、DFF45和lamin B促进细胞凋亡.     

DADAG诱导白血病L1210细胞凋亡

目的 以小鼠白血病细胞系L1210为对象,探讨半胱天冬氨酸蛋白酶（Caspases）家族成员在二乙酰二脱水卫矛醇（diacetyldianhydrogalactitol,DADAG）诱导肿瘤细胞凋亡过程中的作用。方法 MTT法测定DADAG对L1210细胞的杀伤作用;透射电镜和流式细胞术检测细胞凋亡;Western blot和Caspase-3试剂盒测定Caspase-3活性。结果 与对照组相比,L1210细胞经不同浓度的DADAG（12．0、17．2、24．5、35．0或50．0mg／L）处理72h后,其存活率,分别降至72％、63％、46％、35％和20％。DADAG50．0mg／L处理组的凋亡率、Caspase-3活性和PARP裂解片段较对照组明显升高。Caspase-3抑制剂可部分阻断此过程,而Caspases抑制剂可完全阻断此过程。结论 Caspases家族成员在DADAG诱导L1210细胞凋亡中发挥重要的作用。     

乙二酰二脱水卫矛醇对小鼠移植性肝癌H_(22)肿瘤生长和血管生成的抑制作用

目的:研究乙二酰二脱水卫矛醇(DADAG)在体内对肿瘤生长和血管生成的抑制作用及其机制。方法:采用小鼠H22模型观察DADAG对肿瘤生长的影响;免疫组化和W estern blot法分别检测DADAG对肿瘤组织中微血管密度(MVD)和血管内皮生长因子(VEGF)以及转录因子Sp1表达的影响。结果:DAD-AG(5和10 mg.kg-1.d-1)可以浓度依赖性地降低小鼠瘤重(抑制率分别为29.8%和60.2%)和MVD(抑制率分别为38.9%和66.7%),引起肿瘤组织坏死,降低VEGF及Sp1的表达量,但无明显肝、肾毒性。结论:DADAG可以抑制小鼠H22移植瘤的生长和血管生成,下调VEGF及Sp1的表达是其可能的作用机制之一。     

左旋-二脱水伊地醇双甲磺酸酯诱导HL-60细胞凋亡机制的研究

目的:以人原髓细胞白血病细胞HL-60为例,观察左旋-二脱水伊地醇双甲磺酸酯(DMDAI-L)对HL-60细胞的诱导凋亡作用,初步探讨其作用机制。方法:通过酶解可见光底物DEVD-p NA测定给药前后HL-60细胞内的caspase-3酶活性;膜电位依赖性结合的荧光探针JC-1标记法观察给药前后细胞线粒体膜电位(△Ψm)的荧光变化。结果:DMDAI-L 1.25,2.5,5,10和20μg·ml-1剂量组作用24 h后,HL-60细胞内的caspase-3酶活性显著上升(P<0.05);在DMDAI-L作用下,随着浓度增加及作用时间延长,HL-60细胞内线粒体膜电位明显降低。结论:DMDAI-L诱导HL-60细胞凋亡过程中,其作用机制可能与在一定剂量范围及作用时间内,激活或调节细胞内的caspase-3酶活性、降低细胞线粒体膜电位有关。     

二氢青蒿素诱导HL-60细胞凋亡

目的探讨二氢青蒿素对人早幼粒白血病细胞(HL-60)的治疗作用。方法采用台盼蓝染色法和MTT法测定二氢青蒿素对HL-60细胞存活的影响,吖啶橙/溴化乙啶(AO/EB)荧光双染色、DNA凝胶电泳、流式细胞术检测细胞凋亡,Western印迹分析凋亡相关蛋白的表达。结果二氢青蒿素可抑制HL-60细胞存活,诱导HL-60细胞凋亡,同时降低HL-60细胞Bcl-2蛋白的表达,增加Bax蛋白和凋亡执行蛋白半胱氨酸天冬氨酸蛋白酶(caspase)-3的表达,并呈浓度依赖性。结论二氢青蒿素可诱导HL-60细胞凋亡,其机制可能是通过对线粒体凋亡通路中Bcl-2,Bax和caspase-3蛋白表达的调控而发挥作用。     

毛兰素诱导人白血病HL—60细胞的凋亡

目的：研究毛兰素对HL－60细胞增殖的抑制作用,探讨其诱导细胞凋亡的机制。方法：用MTT比色法测定了毛兰素对HL－60细胞增殖的抑制作用：应用荧光显微镜、透射电镜、DNA电泳及流式细胞仪观察了药物对细胞凋亡的诱导作用,并用免疫组化的方法从基因水平阐述了凋亡的发生。结果：毛兰素20－81．9nmol/L在72h内显著抑制HL－60细胞增殖,作用24h后,对HL－60细胞的IC50为38nmol/L,而阳性对照药长春新碱对HL－60细胞的IC50为101nmol/L,前者明显优于后者;形态学观察可见凋亡的特征性改变;琼脂糖电泳出现典型的DNA“ladder”;流式细胞仪结果表明细胞被阻滞于G2／M期;免疫组化可见bcl-2表达下降,bax表达升高。结论：毛兰素显著抑制HL－60细胞的生长,该抑制作用可能是通过诱导细胞凋亡和改变HL－60细胞bcl-2和bax基因的表达而实现的。     

冬凌草甲素诱导HL-60细胞凋亡

目的　研究冬凌草甲素诱导人白血病HL 6 0细胞凋亡的作用。方法　形态学观察 ,DNA凝胶电泳及流式细胞术。结果　冬凌草甲素能显著地诱导HL 6 0细胞发生凋亡 ,其作用呈明显的浓度效应关系和时间依赖性。形态学观察可见凋亡小体的形成 ,琼脂糖凝胶电泳可见明显的DNA梯带 ;流式细胞仪检测到G1亚峰。结论　冬凌草甲素能诱导HL 6 0细胞凋亡 ,并与其细胞杀伤活性相互平行 ,提示冬凌草甲素的抗癌活性与诱导肿瘤细胞凋亡相关     

金喜素诱导HL-60细胞凋亡依赖caspase活化

目的　探讨金喜素诱导急性白血病细胞凋亡的生化机制。方法　采用MTT法测定金喜素对HL 6 0细胞的杀伤作用 ;通过形态学、DNA凝胶电泳及AnnexinVFITC染色 ,研究金喜素对靶细胞的促凋亡活性 ;采用caspase 8、3特异性抑制剂IETD fmk、DEVD CHO ,分析金喜素介导的靶细胞凋亡与caspase活化的关系。结果　经 0 1μmol·L-1金喜素处理至 8、12及 16h时 ,HL 6 0细胞的存活率依次降至6 2 %± 12 %、、43%± 15 %及 32 %± 10 % ,低于对照 (P <0 0 5 ) ,同时 ,靶细胞逐渐出现磷脂酰丝氨酸外化 ,并产生梯状DNA及凋亡小体 ;经caspase抑制剂与金喜素联合处理12、16h时 ,HL 6 0细胞的存活率高于单用金喜素组 ,分别为77%± 14%、6 5 %± 16 % (IETD fmk组 )与 74%± 12 %、6 0 %± 11% (DEVD CHO组 ) ,同时 ,靶细胞的梯状DNA与凋亡小体的诱生也明显受抑。结论　金喜素对HL 6 0细胞具有较强的促凋亡作用 ,该过程可能依赖caspase 8、caspase 3的活化     

Inhibition by vitamin C of apoptosis induced by N-nitrosamines in HepG2 and HL-60 cells

The aim of this study was to evaluate the effect of vitamin C towards N-nitrosopyrrolidine (NPYR)- and N-nitrosodimethylamine (NDMA)-induced apoptosis in human hepatoma (HepG2) and leukemia (HL-60) cell lines using flow cytometry analysis and the terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay (TUNEL). None of the vitamin C concentrations tested (1-100 microM) caused cytotoxicity in HepG2 cells. However, there were significant losses of HL-60 cells viability, measured by MTT assay, 72 h after treatment with 50 and 100 microM vitamin C (29 and 46%, respectively). Moreover, an increase of lactate dehydrogenase release was significant with 50 microM at 72 h (28%) and with 100 microM of vitamin C at 48 and 72 h (27 and 36%, respectively). Also, the percentage of apoptotic HL-60 cells found in TUNEL assay increased to 21% when they were treated with 100 microM vitamin C for 72 h. Thus, in subsequent simultaneous treatments with NPYR (30 and 50 mM) or NDMA (27 and 68 mM) and vitamin C, concentrations of 5-50 microM vitamin C were used. Our results revealed that vitamin C, at all concentrations and times tested, reduced the apoptosis induced by NPYR and NDMA in both cell lines, showing a similar effect in HepG2 and HL-60 cells towards NPYR (50 mM)--65 and 63% of reduction, respectively--whereas towards NDMA (27 mM) the inhibition was higher in HL-60 than in HepG2 cells--75 and 57%, respectively. Therefore, our findings suggest that inhibition of apoptosis may be one of the mechanisms by which vitamin C exerts its protective effect.     

Cytotoxic evaluation and induction of mitochondria-mediated apoptosis in human leukaemia HL-60 cells by Carissa spinarum stem isolate

Objective To evaluate Carissa spinarum stem isolate for its anti‐cancer therapeutic potential. Methods The n‐butanol fraction of aqueous extract from Carissa spinarum stem was assessed for its cytotoxic and pro‐apoptotic activity. Key findings We report for the first time the anti‐cancer potential of C. spinarum stem aqueous extract (CSE) and its n‐butanol fraction (CSF). Both inhibited cell proliferation of various human cancer cell lines in which leukaemia HL‐60 cells treated with CSF showed maximum growth inhibition having an inhibitory concentration (IC₅₀) value of 34.58 ± 0.91 µg/ml. In addition, CSF induced concentration‐dependent apoptosis in HL‐60 cells as measured by various end‐points (e.g. Annexin V binding, DNA laddering, apoptotic body formation and an increase in hypodiploid subG0 DNA content). Moreover, persistent levels of reactive oxygen species caused translocation of Bax to mitochondria and Bcl‐2 degradation, which led to loss of mitochondrial membrane potential and release of cytochrome c to the cytosol. These events were associated with significant activation of caspase‐3, caspase‐6 and caspase‐9 leading to poly (ADP‐ribose) polymerase cleavage. Conclusion All the above parameters revealed that CSF induced apoptosis through the mitochondrial dependent pathway in HL‐60 cells.     

槲皮素诱导人白血病HL-60细胞凋亡(英文)

目的:研究槲皮素是否能诱导人白血病HL-60细胞凋亡.方法:应用琼脂糖凝胶电泳法观察DNA碎片;采用流式细胞仪检测DNA断裂;电镜技术观察凋亡的形态学改变,用MTT测定法测定细胞增殖.结果:槲皮素15-120 μmol·L~(-1)诱导HL-60细胞凋亡,电镜观察到典型的形态学改变,电泳显示梯状条带,槲皮素能剂量依赖性地触发DNA降解及抑制细胞增生(IG_(50)和95％可信区间分别为43(30-61)μmol·L~(-1).结论:槲皮素诱导人白血病HL-60细胞凋亡.     

新型反义寡核苷酸F951对HL60细胞Bcl-2基因表达及细胞增殖的抑制作用

目的　研究新型反义寡核苷酸F951对白血病细胞Bcl- 2基因表达及细胞增殖的影响。方法　不同浓度的F951与HL60细胞共培养后,采用台盼蓝拒染法、MTT比色法检测HL60细胞增殖,用流式细胞术和RT -PCR法检测Bcl- 2蛋白及其mRNA表达,DNA片段化分析法检测凋亡细胞。结果　5, 10, 20μmol·L-1F951分别与HL60细胞共孵育1~5d,细胞生长明显受抑,这一抑制作用随F951浓度的升高和作用时间的延长而增强。MTTA值与未处理组相比F951 5, 10, 20μmol·L-1组细胞抑制率分别为: 20 .56%、37 .66%、54 .11%与对照组相比差异均有显著性;F951处理后HL60细胞Bcl 2mRNA水平下降,Bcl- 2蛋白减少;凝胶电泳可见典型的梯形带,且随着浓度提高诱导DNALadder的作用更加明显。结论　F951可下调Bcl -2基因表达,促进细胞凋亡而抑制白血病细胞增殖。     

Induction of apoptosis by luteolin through cleavage of Bcl-2 family in human leukemia HL-60 cells

In our study, luteolin has shown its apoptosis-inducing potent in HL-60 cells with its 76.5% apoptotic ratio of 100 microM treatment. When HL-60 cells were treated with 60 microM of luteolin, DNA ladders were visible at 6 h and increased from 6-12 h after treatment. Luteolin could decrease the mitochondrial membrane potential, trigger cytochrome c released to cytosol, and subsequently induce the processing of procaspase-9 and procaspase-3, which were followed by the cleavage of poly-(ADP-ribose) polymerase (PARP) and DNA fragmentation factor (DFF-45). The cleavage of the proapoptotic Bcl-2 proteins, such as Bad and Bax to produce their truncated forms, and the cleavage of the antiapoptotic Bcl-2 proteins, such as Bcl-2 and Bcl-XL, into their potent pro-apoptotic fragments were detected in our study. From the results, we suggested that the structure of luteolin contributes to its potent in inducing apoptosis in HL-60 cells, and the mitochondrial pathway might play an important role in the luteolin-induced apoptosis. The induction of apoptosis by luteolin may offer a pivotal mechanism for its cancertherapeutic and chemopreventive action.