二烯丙基二硫作用于HL-60细胞后凋亡相关基因的差异表达

背景与目的:二烯丙基二硫(diallyl disulfide,DADS)对多种肿瘤细胞有促凋亡作用,白血病是儿童最常见的恶性肿瘤,近期研究提示DADS能够在体外诱导人白血病细胞发生凋亡,但其具体作用机制尚不清楚.本实验旨在研究DADS诱导人白血病细胞HL-60凋亡的生物学效应,并探讨其分子机制.方法:运用DNA含量分析、Annexin V/PI双标记流式细胞仪、DNA琼脂糖凝胶电泳以及透射电子显微镜形态学观察等方法来证实细胞凋亡.通过基因芯片检测60 μmol/L DADS作用于HL-60细胞4 h后凋亡相关基因的表达谱,采用RT-PCR技术验证上调基因Fas-L和下调基因Bag-1.结果:15、30、60和120 μmol/L DADS作用于HL-60细胞24 h后,DNA含量分析出现了明显的亚二倍体峰;60 μmol/L DADS作用4、8、12、24 h后,Annexin V/PI双标流式细胞仪检测表明早期凋亡细胞显著增加.60 μmol/L DADS作用24 h后,在DNA琼脂糖凝胶上可见特征性的梯形条带.电子显微镜观察到细胞体积缩小,核浓缩和凋亡小体形成等典型的形态学改变.通过基因芯片检测发现,60 μmol/L DADS作用4 h后有8个凋亡相关基因表达差异显著,选择其中Fas-L和Bag-1两个基因运用RT-PCR技术进行验证,其结果与基因芯片结果一致.结论:DADS能够诱导人白血病细胞HL-60凋亡,这可能是多个基因和多条信号转导通路共同作用的结果.     

亚细胞蛋白质组学技术分析MG132诱导HL-60细胞G2/M期阻滞的分子机制

背景与目的：蛋白酶体抑制剂能够诱导多种肿瘤细胞凋亡,是一种有应用前景的抗肿瘤制剂。本研究通过对蛋白酶体抑制剂——MG132诱导G2／M期阻滞的HL-60细胞核蛋白进行蛋白质组学分析,探索参与HL-60细胞G2／M期阻滞调控的相关蛋白。方法：流式细胞术分析MG132处理的HL-60细胞周期,选取合适的时间点,提取细胞核,光镜和Western blot检测细胞核纯度,裂解制样,通过二维电泳和MALDI-TOF-TOF串联质谱分析,鉴定表达显著差异的细胞核蛋白。结果：HL-60细胞在被2．5μmol／L MG132诱导凋亡之前8h,有明显的G2／M期阻滞发生：提取阻滞发生时和阻滞发生前的HL-60细胞核蛋白,二维电泳分析获得23个差异表达的蛋白点,质谱鉴定了8个核蛋白。结论：质谱鉴定的eIF5A、mRNA前体剪接因子等蛋白可能参与HL-60细胞的GJM周期阻滞调控。为研究蛋白酶体抑制剂诱导白血病细胞周期阻滞及凋亡的分子机制提供了一些线索。     

DADS通过MAPK和PI3K/Akt 信号通路下调Mcl-1诱导白血病细胞凋亡*

目的:二烯丙基二硫（DADS）为天然植物大蒜中的提取物,能抑制多种肿瘤细胞生长,本文探讨丝裂原激活的蛋白激酶（MAPKs）、3- 磷酸肌醇激酶（PI 3K/Akt）信号通路和Bcl- 2 家族成员在DADS诱导的人白血病HL- 60细胞凋亡中的作用。方法:利用流式细胞术检测DADS 诱导的白血病细胞凋亡,Western blot研究MAPKs和PI 3K/Akt信号通路在DADS 诱导的人白血病HL- 60细胞凋亡中的变化及对Bcl- 2 家族凋亡相关蛋白表达的影响。结果:DADS呈浓度和时间依赖性地诱导人白血病HL- 60细胞凋亡,在此过程中ERK/MAPK 和PI 3K/Akt信号通路被抑制,而p38MAPK 信号通路被激活,ERK/MAPK 和PI 3K/Akt信号通路通过降低Mcl-1（myeloid cell leukemia-1）和升高Bax 的表达诱导人白血病细胞凋亡,而p38MAPK 则不是通过调控Mcl-1 和Bax 的表达诱导人白血病细胞凋亡,进一步利用RNA干扰技术沉默Mcl-1 基因可增加DADS对HL- 60细胞增殖抑制和诱导凋亡作用。结论:MAPK 和PI 3K/Akt信号通路通过下调Mcl-1 的表达参与了DADS诱导的HL- 60细胞凋亡作用。      

1,25二羟基维生素D3对体外培养的HL-60细胞的作用

[目的]研究1,25二羟基维生素D3[1,25(OH)2D3]对人HL-60细胞株生长、分化、凋亡及对维生素D受体(VDR)蛋白表达的影响.[方法]在体外用不同浓度的1,25(OH)2D3作用于对数生长期的HL-60细胞.甲基噻唑基四唑(MTT)比色法分析细胞增殖抑制作用,硝基四氮唑蓝(NBT)还原实验法分析HL-60细胞的分化指标,末端脱氧核糖核酸转移酶介导的dUTP缺口末端标记染色法(TUNEL)检测细胞晚期凋亡的变化,免疫细胞化学法检测VDR蛋白表达.[结果]不同浓度的1,25(OH)2D3作用后均可抑制HL-60细胞的生长,呈剂量和时间依赖性;可诱导HL-60细胞向成熟粒细胞分化并促其凋亡.1,25(OH)2D3作用前后HL-60细胞均表达VDR蛋白,药物作用后VDR蛋白表达上调.[结论]1,25(OH)2D3在一定浓度范围内可抑制HL-60细胞增殖,诱导细胞分化及凋亡,使VDR蛋白表达上调.     

二烯丙基二硫增强胃癌细胞对5-Fu敏感性的研究

目的探讨二烯丙基二硫(DADS)对5-Fu诱导胃癌MGC803细胞增殖与凋亡的作用及机制。方法采用四甲基偶氮唑蓝比色法(MTT),测定DADS对5-Fu诱导MGC803细胞增殖活性的作用;应用流式细胞仪检测细胞凋亡率;Westernblot检测MGC803细胞Bcl-2,Bax,Mcl-1蛋白的表达情况。结果1mg/L、3mg/L的DADS分别与5-Fu联合应用,可增强5-Fu对MGC803细胞增殖抑制作用。DADS(1mg/L)能促进5-Fu诱导MGC803细胞的凋亡。DADS作用于MGC803细胞后,Bcl-2、Mcl-1蛋白表达水平下调,Bax蛋白表达水平上调呈浓度依赖方式。结论ADS能增强5-Fu对MGC803细胞增殖抑制和诱导凋亡,起化疗增敏作用,可能与其下调Bcl-2、Mcl-1蛋白表达水平,上调Bax蛋白表达水平有关。     

C-jun在二烯丙基二硫诱导白血病细胞K562凋亡过程中的作用

目的探讨c-jun在二烯丙基二硫(DADS)诱导白血病细胞K562凋亡中的作用及机制。方法通过RT-PCR检测caspase3 mRNA的表达变化,观察DADS诱导K562细胞凋亡作用;RT-PCR从mRNA水平检测c-jun在DADS诱导K562细胞凋亡过程中的表达变化;免疫组化染色从蛋白水平检测p-c-jun(ser73)在DADS诱导K562细胞凋亡中的表达变化。结果 1)随DADS作用时间延长,caspase3的表达越来越强;2)在mRNA水平,DADS作用K562细胞3 h后,随DADS作用时间的延长,c-jun mRNA表达与空白对照组比较差异无统计学意义(P>0.05);3)在蛋白水平,DADS作用K562细胞24 h后,p-c-jun(ser73)的表达增加(P<0.05)。结论 DADS诱导K562细胞凋亡呈时间依赖性,其机制可能与c-jun的ser73位点磷酸化有关。     

p53和Bcl-2 mRNA表达在三七皂苷R1诱导HL-60细胞凋亡中的作用

目的：探讨三七皂苷R1诱导HL-60细胞凋亡的作用机制.方法：采用MTT比色法观察三七皂苷R1对人白血病细胞株HL-60细胞增殖的抑制作用.采用流式细胞术检测细胞凋亡改变,并以RT-PCR检测凋亡调节基因p53、Bcl-2的表达.结果：三七皂苷R1能明显抑制人白血病细胞株HL-60细胞的生长,且呈时间和浓度依赖性.三七皂苷R1作用后人白血病细胞株HL-60细胞呈现凋亡特征,流式细胞术显示凋亡细胞比例升高.RT-PCR检测可见p53 mRNA表达显著增加,而Bcl-2 mRNA表达减少.结论：三七皂苷R1能诱导人白血病细胞株HL-60细胞凋亡,其作用可能与凋亡调节基因p53的上调和Bcl-2的下调有关.     

HL-60细胞向单核系和粒系分化的比较蛋白质组学研究

背景与目的：已有研究发现NSC67657和全反式维甲酸可以诱导HL-60细胞分别向单核系和粒系分化。本研究比较分析不同诱导剂诱导HL-60细胞向单核系和粒系分化前后以及分化中的蛋白表达差异,发现与单核系和粒系分化有关的关键蛋白。方法：分别采用粒系分化诱导剂全反式维甲酸和单核系分化诱导剂NSC67657诱导HL-60细胞分化,MTT法检测细胞增殖情况：流式细胞技术分析细胞表面特异性分化抗原（CD11b／CD14）的表达,根据CD14表达情况计算细胞分化百分率;细胞化学染色对HL-60的两系分化进行验证。改良双向电泳分离技术对HL-60细胞全蛋白进行分离,PDQuest软件分析寻找差异蛋白点,基质辅助激光解吸-飞行时间质谱（MALDI-TOFMS）对蛋白点进行分析,RT-PCR和免疫印迹对差异蛋白ICAT进行验证。结果：全反式维甲酸和NSC67657均抑制HL-60细胞增殖,并分别诱导HL-60细胞向粒系和单核系分化。在2μmol／LATRA和10μmol／LNSC67657作用5d后．CD11b和CD14的表达均在90％以上,细胞化学染色支持细胞两系分化的结论。蛋白质组学分析表明,HL-60细胞分别向粒系和单核系分化后,有25个差异蛋白点的变化趋势在两系分化中是相同的,有10个差异蛋白点在单核系分化后表达有差异。有15个差异蛋白点在粒系分化后表达有差异：ICAT是其中差异蛋白之一,通过基因和蛋白水平验证．发现ICAT在NSC67657诱导HL-60细胞单核系分化过程中表达升高,而在粒系和非处理细胞中表达无显著性差异。结论：双向电泳／MOLDI-TOFMS对HL-60细胞分化前后细胞全蛋白进行分析．发现了一批与两系分化有关的蛋白分子．为关键蛋白的筛选及其功能研究提供了重要的启示。     

可溶性CD40配体对白血病HL-60细胞Caspase-3及Caspase-8表达的影响

目的 Caspase-3和Caspase-8在多种肿瘤中异常表达,与白血病的疗效等密切相关.本研究分析可溶性CD40配体(soluble CD40 ligand,sCD40L)对人白血病HL-60细胞Caspase-3及Caspase-8表达的影响,探讨其对HL-60细胞的作用机制.方法 2.0、4.0和6.0 mg/L的sCD40L作用HL-60细胞48 h,采用流式细胞术检测HL-60细胞凋亡水平及细胞周期,RT-PCR检测HL-60细胞中Caspase-3和Caspase-8基因的表达水平,蛋白质免疫印迹法检测HL-60细胞中Caspase-3和Caspase-8的蛋白表达.结果 2.0、4.0和6.0 mg/L的sCD40L作用HL-60细胞48 h后,浓度依赖性诱导HL-60细胞的凋亡,凋亡率分别为(48.17±3.22)％、(60.73±5.46)％及(71.26±5.83)％,与对照组(36.42±2.75)％比较,差异有统计学意义,F=36.373,P=0.003.sCD40L阻滞HL-60细胞在G0/G1期,RT-PCR结果显示,Caspase-3和Caspase-8 mRNA的表达上调;蛋白质印迹法结果显示,Caspase-3和Caspase-8蛋白表达增强.结论 sCD40L在体外能够以浓度依赖性促进HL-60细胞凋亡,阻滞细胞在G0/G1期,其可能机制是通过激活Caspase-3和Caspase-8.     

DADS抑制SW480细胞系生长增殖及CK19蛋白质分子鉴定

目的:观察不同浓度和作用时间二烯丙基二硫(DADS)对SW480细胞的生长抑制作用,应用前期蛋白质组学筛出的部分差异表达蛋白质分子,进行进一步分析与鉴定.方法:采用MTT、细胞计数法;施用流式细胞仪、RT-PCR和Western blotting方法,检测50 靏/mL DADS对SW480细胞的凋亡率、CK19 mRNA和蛋白的表达水平.结果:MTT法显示,DADS能明显抑制SW480细胞生长增殖,呈浓度和时间依赖性,细胞生长增殖速度明显减慢.细胞计数表明,当DADS浓度增加时,SW480细胞群体倍增时间延长,与对照组比较,差异有统计学意义,P<0.05.流式细胞仪分析显示,50 靏/mL DADS使SW480细胞凋亡率增加.RT-PCR和Western blotting结果证实,50 靏/mL DADS处理SW480细胞后,CK19 mRNA和蛋白表达较对照组降低,差异有统计学意义,P<0.05.结论:DADS抑制SW480细胞系生长增殖,可能与CK19表达下调,促进细胞凋亡有关.     

Involvement of Mcl1 in diallyl disulfide-induced G2/M cell cycle arrest in HL-60 cells

Diallyl disulfide (DADS) has shown potential as a therapeutic agent in various cancers. Previously, we found that myeloid cell leukemia sequence 1 (Mcl1) was downregulated in DADS-induced cell cycle arrest in HL-60 human leukemia cells. Here, we investigated the role of this protein in DADS-induced G2/M cell cycle arrest in HL-60 cells. We demonstrated that DADS treatment significantly increased the proportion of G2/M phase HL-60 cells (P<0.05) and caused a time-dependent significant downregulation of Mcl1 and the cell cycle-related proteins PCNA and CDK1 (P<0.05). Small interfering RNA-mediated knockdown of Mcl1 expression in HL-60 cells arrested the cell cycle in G2/M phase. By co-immunoprecipitation, we demonstrated that Mcl1 associated with PCNA and CDK1 in G2/M cell cycle arrest in DADS-treated HL-60 cells. DADS decreased the interaction of Mcl1 with PCNA and CDK1, leading to G2/M cell cycle arrest in HL-60 cells. Mcl1 plays an important role in DADS-induced G2/M cell cycle arrest in HL-60 human leukemia cells.     

二烯丙基二硫化物诱导胃癌BGC823 细胞周期G2/M期阻滞的机制*

目的:以细胞周期作为抗癌药物新靶点的研究,可能是很有前途的。笔者的前期工作发现,二烯丙基二硫化物（diallyl disulfide,DADS）可抑制人胃癌BGC 823 细胞增殖,其增殖抑制与细胞周期G2/M期阻滞有关;DADS可能是通过抑制细胞分裂周期蛋白25C（Cell division cycle protein 25C,Cdc25C）、cyclinB 1 表达使部分BGC 823 细胞停滞在G2/M期,但G2/M期阻滞的机制还未完全阐明。本研究进一步探讨DADS诱导人胃癌BGC 823 细胞周期G2/M期阻滞的可能机制。方法:RT-PCR 检测Chk1 和Chk2 在mRNA 水平的改变;Western blot检测DADS处理BGC 823 细胞前后细胞周期相关蛋白ATM-RAD3 相关基因（ATM-RAD3-related gene,ATR ）、细胞周期检查点蛋白激酶1（checkpoint kinase1,Chk1）、细胞周期检查点蛋白激酶2（checkpoint kinase2,Chk2）表达和ATR 、Chk1、Chk2 的磷酸化程度;免疫共沉淀检测Chk1、Chk2 与Cdc25C 结合情况。结果:RT-PCR 检测显示,Chk1 和Chk2 的mRNA 水平在处理组与未处理组之间无显著性差异（P>0.05）。 Western blot检测显示,总Chk1 和Chk2 蛋白表达在细胞处理前后均无明显改变,但15mg/LDADS刺激BGC 823 细胞2h 后,处理组细胞Chk1 磷酸化程度明显增加,并呈时间依赖性（P<0.05）,而Chk2 磷酸化程度在处理组与未处理组之间无显著性差异（P>0.05）。 15mg/L DADS 作用15～120min,ATR 磷酸化程度明显增加,呈时间依赖性（P<0.05）,而ATR 表达无改变。免疫共沉淀分析表明,DADS 能促进BGC 823 细胞Chk1 与Cdc25C 结合,而对Chk2 与Cdc25C 结合无影响。结论:DAD诱导人胃癌BGC 823 细胞G2/M期阻滞与Chk1 的活化有关,DADS可能是通过激活ATR 、Chk1,调节Cdc25C 的表达引起人胃癌BGC 823 细胞G2/M期阻滞。      

蛋白酶体抑制剂MG132诱导HL-60细胞凋亡前G2/M期阻滞及机制

背景和目的:蛋白酶体(proteasome)抑制剂能够诱导多种肿瘤细胞凋亡,是一种潜在的有应用前景的抗肿瘤剂.本研究旨在探讨蛋白酶体抑制剂MGl32(Z-Leu-Leu-Leu-CHO)诱导白血病细胞HL-60凋亡和C2/M期阻滞的机制.方法:采用荧光显微镜观察、流式细胞术和免疫印迹研究测定MG132诱导HL-60细胞凋亡和周期阻滞及机制.结果:2μmol/L的MG132能够有效地诱导HL-60细胞凋亡,用药后24 h就显现有细胞凋亡;在MG132诱导HL-60细胞凋亡出现之前有一个明显的G2/M期阻滞,加MG132后12 h时G2/M期时相百分比为63.42±2.02;24 h时加MG132组细胞凋亡为16.67±1.48,与对照组G2/M期时相百分比为7.29±3.01及细胞凋亡为0相比,两者之间有显著性差别(P＜0.01);咖啡因CAF能够减少MG132诱导HL-60细胞出现的G2/M期阻滞,同时也减少凋亡细胞的比例;细胞周期检查点的负调控因子p21waf/cip1蛋白在加MG132处理后3 h有明显的表达,但并未能检测到p53和p27蛋白.结论:MG132诱导HL-60细胞凋亡之前有一个明显的G2/M期阻滞,p21蛋白表达明显上调提示:是p21waf/cip1而不是p53或其同源蛋白参与了其中的调控.     

Knockdown of IARS2 Inhibited Proliferation of Acute Myeloid Leukemia Cells by Regulating p53/p21/PCNA/eIF4E Pathway

IARS2 encodes mitochondrial isoleucine-tRNA synthetase, which mutation may cause multiple diseases. However, the biological function of IARS2 on acute myeloid leukemia (AML) has not yet been identified. In the present study, qRT-PCR was used to determine the expression of IARS2 in K562, THP1, and HL-60 leukemia cells. Additionally the mRNA levels of IARS2 in CD34 cells and AML cells obtained from patients were detected by qRT-PCR. IARS2-shRNA lentiviral vector was established and used to infect acute myeloid leukemia HL-60 cells. qRT-PCR and Western blot analysis were employed to assess the knockdown effect of IARS2. The proliferation rate and cell cycle phase of HL-60 cells after IARS2 knockdown were evaluated by CCK-8 assay and flow cytometry. The PathScan Antibody Array was used to determine the expression of cell cycle-related proteins in HL-60 cells after IARS2 knockdown. The expression of proliferation-related proteins in HL-60 cells after IARS2 knockdown was determined by Western blot analysis. Results showed that IARS2 expression was stable and much higher in HL-60, THP-1, and K562 leukemia cells and AML cells obtained from patients than that of human CD34 cells. Compared with cells of the shCtrl group, IARS2 was markedly knocked down in cells that were transfected with lentivirus encoding shRNA of IARS2 in HL-60 cells (p<0.05). IARS2 knockdown significantly inhibited the proliferation and induced cycle arrest at the G₁ phase in HL-60 cells. Additionally IARS2 knockdown significantly increased the expression of p53 and p21, and decreased the expression of PCNA and eIF4E in HL-60 cells. In conclusion, IARS2 knockdown can inhibit acute myeloid leukemia HL-60 cell proliferation and cause cell cycle arrest at the G₁ phase by regulating the p53/p21/PCNA/eIF4E pathways.     

Detection of a histone-2a related polypeptide in differentiated human myeloid cells (hl-60) and its distribution in human acute leukemia

A human myeloid cell line, HL-60, has been shown to terminally differentiate to mature granulocytes in the presence of dimethylsulfoxide (DMSO) and other compounds. A histone polypeptide (HP) with an apparent molecular weight of 12,500 has been identified among the acid-extractable chromosomal proteins of DMSO-treated HL-60 cells. The detection of HP in total chromatin, total cell proteins or acid extracts of intact HL-60 cells treated with DMSO indicates that HP is present in intact cells and is not generated during the isolation procedures used for preparation of chromatin or histones. No radiolabelled HP was detected when chromatin was isolated from a mixture of radiolabelled mouse cells and HL-60 cells treated with DMSO. The relative increase in the amount of HP in DMSO-treated HL-60 cells correlates with a concomitant decrease of histone H2A. Fingerprint analysis of tryptic digests shows HP to be related to histone H2A. Generation of HP from endogenous and exogenous H2A is probably due to a proteolytic enzyme associated with the chromatin of the differentiated HL-60 cells. HP was not observed in chromatin from a number of human or mouse hematopoietic tissues and cell lines but low levels of HP were detected in human lymphocytes and granulocytes prepared from peripheral blood of normal donors. HP was also detected in leukocytes from patients with acute leukemia. Our results suggest that: (1) HP is a proteolytic product of histone H2A and not a product of an independent gene; (2) the observed level of HP in HL-60 cells is related to the stage of differentiation; and (3) HP is a potential biological marker for human acute leukemia.     

Changes in actin and actin-binding proteins during the differentiation of HL-60 leukemia cells.

Actin and actin-binding proteins form a peripheral network on the cytosolic side of the plasma membrane. These cytoskeleton proteins are involved in functions that require cellular movement and may also have a role in modulating signal transduction during cellular proliferation and differentiation. To measure changes in F-actin and actin-binding proteins during HL-60 differentiation, cells were induced to mature along the granulocytic pathway by exposure to 1 microM retinoic acid (RA) for 5 days and were analyzed for F-actin and actin-binding proteins by flow cytometry. The amounts of F-actin and spectrin in untreated HL-60 cells and in those undergoing differentiation by treatment with the retinoid did not differ. N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)-phallacidin was used to measure F-actin content and a monoclonal antibody followed by fluorescence isothiocyanate-conjugated goat anti-mouse immunoglobulin antibody was used to measure the content of spectrin; cells were analyzed by flow cytometry. In contrast, cells exposed to RA contained larger amounts of alpha-actinin, vinculin, talin, lipocortin I, and lipocortin II, as determined with their respective antibodies followed by flow cytometric analysis as described above. An RA-supersensitive clone of HL-60, designated HL-60/S4, exhibited lower constitutive levels of alpha-actinin, vinculin, and talin but a higher constitutive level of lipocortin II than parental cells. Treatment of HL-60/S4 with RA led to increases in vinculin, talin, lipocortin I, and lipocortin II. An RA-resistant clone, designated HL-60/R3, constitutively expressed larger amounts of alpha-actinin, vinculin, lipocortin I, and lipocortin II than parental HL-60 cells. Treatment of HL-60/R3 with RA resulted in decreases in the amounts of these actin-binding proteins. Changes in actin-binding proteins that occur during the differentiation of HL-60 cells suggest that these proteins may be of importance to the expression of the mature phenotype.