HL-60细胞分化与凋亡关系的初步研究

目的探讨HL-60细胞分化与凋亡的初步关系,指导白血病的联合化疗.方法NBT还原试验检测细胞分化、流式细胞术(FCM)检测细胞凋亡及bcl-2、c-myc蛋白的表达,观察分别经ATRA、TPA诱导分化的HL-60细胞对VP-16的凋亡反应.结果与对照组相比,经ATRA、TPA分化的HL-60细胞bcl-2、c-myc蛋白表达都明显降低(P＜0.05),其中以TPA下调c-myc蛋白的幅度最大(76%);对VP-16的诱导反应,经TPA分化的HL-60细胞凋亡率明显减少(P＜0.05),而经ATRA分化的细胞凋亡率则无明显变化(P＞0.05).结论HL-60细胞对VP-16的凋亡诱导反应与bcl-2、c-myc蛋白的下调表达程度有关;分化诱导剂ATRA与低剂量的VP-16联合应用可望改善AML的化疗效果,并且以后者先用效果更好.     

鬼臼叉甙诱导HL－60细胞分化时c－myc蛋白的表达

目的：观察小剂量鬼臼叉甙对ＨＬ－６０细胞的诱导分化作用和对ｃ－ｍｙｃ蛋白表达的影响。方法：应用加入鬼臼叉甙（ＶＰ－１６）和维甲酸（ＲＡ）的含２０％小牛血清的培养基培养人类早幼粒细胞株（ＨＬ－６０），分别在培养后１、２、４、６ｄ测定细胞各时相的ｃ－ｍｙｃ蛋白水平。结合细胞形态、细胞化学和氯化硝基四氮唑蓝（ＮＢＴ）还原试验，观察ＶＰ－１６、ＲＡ对ＨＬ－６０细胞的诱导分化作用及其与ｃ－ｍｙｃ蛋白表达的关系。结果：与ＲＡ一样，小剂量ＶＰ－１６能诱导ＨＬ－６０细胞向粒系分化。并且在ＨＬ－６０细胞分化过程中ｃ－ｍｙｃ蛋白水平明显降低。ＶＰ－１６处理的ＨＬ－６０细胞其ｃ－ｍｙｃ蛋白降低与其诱导分化作用呈负相关。结论：实验结果提示，ｃ－ｍｙｃ原癌基因表达的变化可能是ＶＰ－１６诱导ＨＬ－６０细胞分化的机制之一。     

RAPID ALTERATIONS IN PROTEIN KINASE C ACTIVITY AND INTRACELLULAR DISTRIBUTION DURING PHORBOL ESTER-INDUCED HL-60 CELL MICROPHAGE-LIKE DIFFERENTIATION

Alterations of protein kinase c activity were studied in the human leukemic cell line, HL-60, during induction of macropahge-like differentiation by tetradecenoyl phorbol 13-acetate (TPA). TPA added to intact HL-60 cells caused a concentration-dependent decrease in the total detergent-solubilized protein kinase C activity within an hour. This decrease in protein kinase c acticity in extracts of the cells did not appear to be due to an inhibitor of the kinase induced by TPA. DEAE-cellulose chromatography showed that the total decrease was caused by a decrease in the level of protein kinase C activity in the cytosol, since a higher peak of activity eluted at NaCl concentration greater than 0.125 M was found in the particulate preparation. Trifluoperazine, an inhibitor of protein kinase C activity in cell extracts, was however found to raise the protein kinase C activity when added to intact HL-60 cells. Nevertheless, trifluoperazine, when added in combination with TPA, did not overcome the TPA-induced decrease in protein kinase C activity.     

THE EFFECTS OF RETINOIC ACID ON EXPRESSION OF C-MYC, C-FOS IN LEUKEMIC PROMYELOCYTES

The expression of c-myc, c-fos of leukemic promyelocytes (HL-60 and acute promyelocytic leukemia cells) from 18 acute promyelocytic leukemia (APL) patients treated with all-trans retinoic acid (RA) in vitro was studied. There was no expression of c-fos in HL-60 cells and APL cells from 17 patients. But in one case, a slight expression of c-fos in leukemic cells was observed, and the alteration of expression level was found during the treatment of the cells with RA in vitro. The expression of c-myc in HL-60 cells induced by RA was altered, decrease in the early, increase in the middle, and decline in the later stage were found. The c-myc expression in leukemic cells of eighteen APL patients was variable. There was c-myc expression in eleven APL cells, but no expression in the others. The APL cells with c-myc expression were treated with RA in vitro to observe the kinetic changes of c-myc RNA level. The results showed that the expression of c-myc was gradually decreased except in few cases. Using in situ hybridization technique for detecting the alteration of c-myc expression in leukemic cells of two APL patients. the high level of c-myc before RA treatment and low level of c-myc expression after obtaining complete remission induced by RA were found. The possibility of different proto-oncogenes implicated differentiation was discussed.     

胎儿组织int—2,Ki—ras和c—myc原癌基因的Southern blot杂交分析

本文用int-2、v-ki-ras和c-myc三种癌基因探针和核酸分子杂交技术,对6例胎儿(20或23周)的五种组织共21个DNA标本进行了Southern blot分析。实验结果表明,3例胚胎的10个DNA标本的int-2位点呈现BamHI多态性片段,ki-ras基因无扩增或重排。1例胚胎肾组织出现1条扩增的5.1kb c-myc杂交片段。上述结果有助于进一步研究胚胎组织中原癌基因的表达状态和肿瘤组织分化发育之间的潜在关系。     

PBK/TOPK在TPA诱导的人HL-60细胞分化中的表达及意义

目的:研究PBK/TOPK在TPA(佛波酯)诱导白血病细胞HL-60的分化时的表达及意义.方法:细胞化学染色法观察药物作用后细胞形态的变化;流式细胞仪检测药物对HL-60细胞周期及细胞表面分化抗原CD11b,CD14,CD13和CD33表达的影响;用western Blot法检测PBK/TOPK在HL-60细胞分化前后表达的变化.结果:经5.1 nmol/L TPA处理72 h后,NBT阳性细胞数和CD11b,CD13,CD14表达是增加的,HL-60细胞体积缩小,核浆比例减低,核仁减少甚至消失,核形态扭曲折迭或分叶;PBK/TOPK在HL-60细胞向成熟分化后表达下调.结论:TPA能抑制白血病细胞HL-60的增殖,并诱导其向成熟单核、粒细胞分化,在此过程中,PBK/TOPK表达是下调的,但Pho-PBK/TOPK的表达是增加的.     

Antisense RNA of Survivin Gene Inhibits the Proliferation of Leukemia Cells and Sensitizes Leukemia Cell Line to Taxol-induced Apoptosis

The effects of survivin antisense RNA on proliferation of leukemia cell line HL-60 and taxol-induced chemotherapy was explored. A cDNA fragment of survivin obtained by RT-PCR was inserted into a plamid vector named pcDNA3 in the reverse direction. The vector encoding antisense RNA of survivin was confirmed by restriction enzyme digestion and DNA sequencing. The recombinant plasmid was delivered into HL-60 cells by electroporation. Growth curves were plotted based on cell counting. Trypan blue dye exclusion assay and MTT assay were carried out after the cells were incubated with taxol. DNA gel electrophoresis and nuclear staining were performed for cell apoptosis assay. The correct construction of the recombinant plasmid has been identified by restriction enzyme digestion and DNA sequencing. A stable down-regulation has been achieved in HL-60 SVVas cells after G418 selection. Compared to HL-60 cells, the proliferation of HL-60 SVVas cells was significantly inhibited （P〈0.05）. Cytotoxicity assays indicated that IC50 of HL-60 SVVas for taxol was relatively lower than controls （P〈0.01）. Apoptosis assays revealed that taxol-induced apoptosis was detected in HL-60 SVVas cells incubated with 50 ng/ml taxol for 12 h, while in HL-60 cells incubated with 100 ng/ml taxol for 72 h. It was suggested that Survivin antisense RNA could inhibit the proliferation of HL-60 cells and enhance taxol-induced apoptosis in HL-60 cells, which may lay an experimental foundation for further research on gene therapy in leukemia.     

七种癌基因在HL-60-AR细胞中的表达及药物诱导分化后的变化

用Northern杂交和斑点杂交方法分别探测HL-60-AR细胞中七种癌基因的表达及其在诱导分化后的变化。结果表明,在HL-60-AR细胞中c-myc基因高度活跃表达,H-ras基因次之,fos、sis、abl和erb-B基因表达微弱,而K-ras基因表达极微弱或检测不出。当HL-60-AR细胞被药物诱导成熟分化后,c-myc基因表达大为下降,H-ras、fos、sis、abl和erb-B基因表达亦相应降低,而K-ras的表达则无变化。对诱导分化前后c-myc基因拷贝数的比较分析表明,c-myc基因表达下降可能主要发生在基因的转录或/和转录后调节水平。     

各种分化诱导剂对人白血病HL-60细胞内中性糖脂合成的影响

作者采用[~(14)C]-标记的半乳糖研究HL-60细胞分化过程中中性糖脂的合成,以了解佛波酯(TPA)、二甲基亚砜(DMSO]、GM3(NeuAc-Gal-Glc-Cer)、GMI[Gal-GalNAc-(NeuAc)Gal-Glc-Cer]和硫脂对其生物合成的影响。TPA、GM3不但能诱导HL-60细胞分化为单核细胞,而且明显地增加[~(14)C]-半乳糖的掺入。TPAGM3在不同程度上促进[~(14)C]-标记的中性糖脂合成,其中主要促进二己糖基神经酰胺(GL2)合成。DMSO诱导HL-60细胞分化为粒细胞,不仅显著地抑制了[~(14)C]-半乳糖掺入,而且抑制了[~(14)C]-标记的中性糖脂的合成,但是促进-已糖基神经酰胺[GL1]的合成。这些结果提示中性糖脂的生物合成与HL-60细胞的分化有关。     

癌化学预防药维胺酸的药理学研究

维胺酸(N-4-(hydroxycarbophenyl)-retinamide;RⅡ)在30～50mg/kg的剂量下对大鼠移植性软骨肉瘤有明显治疗作用。 低浓度的RⅡ对HL-60细胞有较弱的分化诱导活性,同时加入S86019可使其活性增强。流式细胞光度术分析表明,RⅡ可使HL-60细胞产生G_1期阻断,与S86019联合应用有良好协同阻断效应,使90％细胞积聚在G_1期,Northern blot分析表明,用RⅡ和S86019联合处理HL-60细胞12h后,c-myc表达明显受到抑制,与DNA合成密切相关的胸腺嘧啶核苷酸合成酶mRNA表达也受到抑制。     

反转录聚合酶链反应检测自身免疫疾病和正常人外周血淋巴细胞C-myc癌基因的表达

目的：探讨癌基因Ｃ－ｍｙｃ在自身免疫病患者和正常人外周血淋巴细胞上的表达情况。方法：分离正常人及系统性红斑狼疮（ＳＬＥ）、类风湿性关节炎（ＲＡ）患者外周血淋巴细胞，采用异硫氰酸胍一步法提取ＲＮＡ，利用反转录聚合酶链反应（ＲＴ－ＰＣＲ）技术，比较正常人及自身免疫病患者外周血淋巴细胞Ｃ－ｍｙｃｍＲＮＡ表达程度。结果：ＳＬＥ患者外周血淋巴细胞Ｃ－ｍｙｃｍＲＮＡ表达较正常人和ＲＡ患者高，ＲＡ和正常人之间没有差异。ＨＬ－６０细胞系Ｃ－ｍｙｃｍＲＮＡ表达最强，ＧＢＣ胃癌细胞株较正常人为高。结论：提示Ｃ－ｍｙｃｍＲＮＡ在肿瘤细胞株及ＳＬＥ患者外周血淋巴细胞上有较高的表达，认为自身免疫病原癌基因的表达在其发病机理中具有重要的作用。     

c-myc gene inactivation during induction of nasopharyngeal carcinoma cells with retinoic acid

Ｒｅｔｉｎｏｉｃａｃｉｄ (ＲＡ) ,ａｎａｔｕｒａｌｄｅｒｉｖａｔｉｖｅｏｆｖｉｔａｍｉｎＡ ,ｉｓａｐｏｔｅｎｔｃｅｌｌｇｒｏｗｔｈｉｎｈｉｂｉｔｏｒａｎｄｉｎｄｕｃｅｒｏｆｄｉｆｆｅｒｅｎｔｉａｔｉｏｎ Ｓｅｖｅｒａｌｓｔｕｄｉｅｓｈａｖｅｄｅｍｏｎｓｔｒａｔｅｄｔｈａｔｒｅｔｉｎｏｉｃａｃｉｄｃｏｕｌｄａｆｆｅｃｔｔｈｅｇｒｏｗｔｈａｎｄｐｈｅｎｏｔｙｐｅｏｆｃａｒｃｉｎｏｍａｃｅｌｌｓ,1 3 　ａｓｗｅｌｌａｓｔｈｅｉｒｇｅｎｅｅｘｐｒｅｓｓｉｏｎａｎｄｒｅｇｕｌａｔｉｏｎ 4 ,5　Ｒｅｔｉｎｏｉｃ…     

Effect of adenovirus-mediated p27 gene expression on the proliferation and apoptosis of HL-60 and Raji cell lines

Background p27 is an essential mediator of cell cycle control,which plays a key negative role in the proliferation and tumorigenesis of certain cell types. Here, we designed this study to explore the possible effects of p27 on the proliferation and apoptosis of HL-60 and Raji cell lines. Methods HL-60 and Raji cells were transfected with p27 via an adenovirus-mediated approach. The efficiency of Adp27 infection and the expression of p27 mRNA and protein were evaluated by X-gal staining, RT-PCR, and flow cytometry. The proliferation and apoptosis of HL-60 and Raji cells were estimated by means of trypan blue staining, M‘l-r assay, Annexin V/PI, and DNA ladderelectrophoresis. Results The infection efficiencies in HL-60 and Raji cells were 40.3% and 32.0%, respectively. RT-PCR and flow cytometry showed that there was significant expression of p27 mRNA and protein in HL-60 and Raji cells infected with Adp27; on the other hand, uninfected HL-60 cells showed faint traces of p27 mRNA and protein and Raji cells showed nearly no signs of p27 mRNA and protein. As demonstrated by a cell growth curve and by an MTT assay, strong time-dependent proliferation inhibition was apparent in HL-60 and Raji cells infected by Adp27. After 72 hours of infection, the Annexin V^ /PI^- apoptotic cell rates in HL-60 and Raji cell lines were 46.9% and 35.7%, respectively, significantly higher than in the control groups (4.7% and 5.6%, respectively). Typical DNA ladder bands were detectable in HL-60 and Raji cells after 48 hours of Adp27 infection. Conclusions Adenoviral vector-mediated p27 gene transfection of HL-60 and Raji cells leads to the inhibition of cellular proliferation and the promotion of cell apoptosis. This technique may provide an approach to gene therapy for leukemia or lymphoma.     

c-myc反义寡核苷酸对HL-60细胞增殖及c-myc基因表达的影响

目的：观察c-myc基因反义寡核苷酸(ASODN)对HL-60细胞增殖及c-myc基因表达的抑制作用．探讨ASODN作为药物进行白血病基因治疗的可行性、方法：应用c-myc反义寡核苷酸封闭HL-60细胞c-myc基因、RTPCR方法检测该基因表达抑制情况．流式细胞仪进行细胞周期分析,倒置显微镜观察细胞形态变化．绘制细胞生长曲线,MTT法检测细胞增殖状态。结果：c-myc基因反义寡核苷酸转染HL-60细胞后,c-myc基因表达明显受抑;S期细胞比值由55.6％降至16．7％;细胞生长受抑,增殖能力减弱,其抑制作用具有序列特异性及剂量依赖性。结论c-myc基因反义寡核苷酸对HKL-60细胞增殖及c-myc基因的表达具有明显的抑制作用,有望成为抑制白血病细胞增殖的核酸药物。     

HL-60细胞内同源盒HOXA1、cDNA基因的克隆

目的：研究同源盒ＨＯＸ基因的表达在ＡＴＲＡ诱导白血病细胞分化中的作用。方法：利用我们建立的一种高效、简单的ｃＤＮＡ克隆方法－ＨＯＸ家庭基因指纹图技术,克隆ＨＬ－６０细胞内的ＨＯＸｃＤＮＡ基因。采用半定量ＲＴ－ＰＣＲ技术初步探讨ＡＴＲＡ对所克隆的ＨＯＸ基因表达的影响。结果：筛选出一个在ＨＬ－６０细胞内有表达的同源盒基因一ＨＯＸＡＩ基因ｃＤＮＡ片段,初步研究证实,此基因的ｍＲＮＡ水平在ＡＴＲＡ的作用下被上调。结论：ＡＴＲＡ可诱导ＨＬ－６０细胞内ＨＯＸＡ１基因表达增强。提示在ＡＴＲＡ诱导细胞分化而治疗恶性肿瘤的分子机制中,包括上调ＨＯＸＡ１基因表达而致白血病细胞分化成熟。     

重组腺病毒介导的反义c-myc基因对HL-60细胞增殖及细胞周期的影响

目的:观察重组反义c-myc腺病毒(Ad-Asc-myc)对急性早幼粒白血病HL-60细胞周期及增殖的影响,探讨其作用的分子机制.方法:将Ad-Asc-myc与鱼精蛋白硫酸盐(Protamine sulfate)混合后转染HL-60细胞,MTF法观察细胞生长曲线,流式细胞仪检测细胞增殖周期,RT-PCR检测c-myc转录变化,免疫细胞化学检测c-myc及增殖细胞核抗原(PCNA)表达变化.结果:Ad-Asc-myc转染HL-60细胞后,细胞生长受抑,细胞周期呈现G1期延长、S期缩短,增殖指数逐渐下降,出现大量凋亡细胞.c-myc基因转录及表达下降,PCNA表达降低.结论:Ad-Asc-myc可使HL-60细胞的生长减缓,增殖能力降低,凋亡细胞增加.其生物学活性与HL-60细胞c-myc和PCNA表达受抑有关.     

各种分化诱导剂对人白血病HL-60细胞中神经节苷脂合成及唾液酸转移酶的影响

作者采用[~(14)C]-半乳糖研究佛波酯(TPA)、二甲基亚砜(DMSO)、GM3(NeuAe-Gal-Gle-cer)等诱导HL-60细胞分化过程中神经节苷酯(Sg)合成及CMP-Neu Ac:LacCer唾液酸转移酶(ST1)活性的变化。TPA、GM3促进HL-60细胞合成[~(14)C]-Gg,也促进GM3的合成。DMSO抑制HL-60细胞合成[~(14)C]-Gg,但促进GM3的合成。各种制剂处理EL-60细胞后,均能使ST1活性升高,但GM3使ST1活性增加不明显,可能是终产物对ST1的反馈抑制。结果提示Gg(GM3)的生物合成和ST1的活性变化与HL-60细胞的分化增殖有关。     

DOWN－REGULATION OF C－MYC ONCOGENE DURING NGF－INDUCED DIFFERENTIATION OF NEUROBLASTOMA CELL LINES

ＤＯＷＮ－ＲＥＧＵＬＡＴＩＯＮＯＦＣ－ＭＹＣＯＮＣＯＧＥＮＥＤＵＲＩＮＧＮＧＦ－ＩＮＤＵＣＥＤＤＩＦＦＥＲＥＮＴＩＡＴＩＯＮＯＦＮＥＵＲＯＢＬＡＳＴＯＭＡＣＥＬＬＬＩＮＥＳＣｈｅｎＪｉｅ（陈杰），ＬｉｕＴｏｎｇｈｕａ（刘彤华）ａｎｄＡｌｏｎｚｏＨＲｏ...