HL-60细胞ATRA诱导后MMP-9/TIMP-1表达的变化

为了检测HL-60细胞经过全反式维甲酸(ATRA)诱导后基质金属蛋白酶(MMP-9、MMP-2)及金属蛋白酶组织抑制剂1(TIMP-1)表达变化,并探讨其变化的意义。采用瑞氏染色观察细胞形态,WST1实验测定细胞增殖变化,NBT还原实验测定细胞分化状态,RT-PCR方法检测MMP-9、MMP-2、TIMP-1、VEGF的mRNA的表达。结果显示,HL-60细胞经ATRA作用24h后,随着细胞增殖降低与分化的发生,MMP-9mRNA表达增加,TIMP-1mRNA和VEGF表达降低,MMP-2mRNA未见明显表达。ATRA诱导HL-60细胞分化后MMP-9表达增加,而TIMP-1表达降低,MMP-9不促进HL-60细胞表达VEGF。     

Differential cell fates induced by all-trans retinoic acid-treated HL-60 human leukemia cells

HL-60 human leukemia cells, differentiated into a neutrophil lineage by all-trans retinoic acid (ATRA) treatment, express three members of the carcinoembryonic antigen (CEA) gene family, CEA-related cell adhesion molecule 1 (CEACAM1; CD66a), CEACAM3 (CD66d), and CEACAM6 (CD66c). CD66d is a neutrophil lineage-specific marker, and CD66a and CD66c are found on epithelial and other cells. HL-60 cells continuously treated with ATRA underwent apoptosis, and cells transiently treated for 1 day underwent cell-cycle arrest, entered into senescence, and exhibited reduced apoptosis with CD66-positive cells accounting for the majority of live cells. CD66 antigens were also induced in NB4 leukemic cells upon continuous treatment with ATRA. NB4 cells underwent apoptosis with a higher frequency in transient versus continuous-treated cells (38% vs. 19% at Day 5), in contrast to HL-60 cells that underwent cell-cycle arrest and senescence when transiently treated with ATRA. CD66 antigens were not induced in transient, ATRA-treated NB4 cells compared with HL-60 cells. Cell-cycle arrest in HL-60 cells involved reduction in expression levels of p21, cyclins D and E, while Rb1 exhibited reduction in protein levels without changes in mRNA levels over the time course of ATRA treatment. Analysis of several proapoptotic proteins implicated the activation of calpain and cleavage of Bax in the intrinsic apoptotic pathway, similar to published studies about the apoptosis of neutrophils. CD1d expression was also induced by ATRA in HL-60 cells and ligation with anti-CD1d antibody-induced apoptosis. In contrast, CD1d-positive primary monocytes were protected from spontaneous apoptosis by CD1d ligation. These studies demonstrate distinct cell fates for ATRA-treated HL-60 cells that provide new insights into ATRA-induced cell differentiation.     

Modulation of death receptor-mediated apoptosis in differentiating human myeloid leukemia HL-60 cells

Differentiating myeloid cells may become resistant to various apoptotic stimuli. In the present study, dimethyl sulfoxide (DMSO) and all-trans retinoic acid (ATRA) were found to modulate the sensitivity of HL-60 cells to death receptor-mediated apoptosis in a time-dependent manner. During the early stages of differentiation, DMSO treatment increased the response of HL-60 cells to tumor necrosis factor alpha; (TNF-alpha), but enhanced responsiveness was lost during later differentiation stages. In contrast, ATRA treatment induced resistance to TNF-alpha-induced apoptosis. HL-60 cells were resistant to Fas-mediated apoptosis but were sensitized by culturing in serum-free conditions. Similar to its effect on TNF-alpha sensitivity, DMSO pretreatment augmented the response to Fas-mediated signaling, which coincided with increased expression of Fas on DMSO-pretreated cells. However, during the later stages of DMSO-induced differentiation, sensitivity to anti-Fas antibody-induced apoptosis declined significantly, although Fas expression was still elevated. The reduced sensitivity to anti-Fas treatment partially correlated with increased Fas-associated phosphatase-1 mRNA expression. Thus, regardless of either Fas up-regulation or potentiation of TNF-alpha-mediated apoptosis during early DMSO-induced differentiation, a slow increase in resistance to apoptosis mediated through these death receptors occurs during DMSO-induced differentiation, which contrasts with the rapid induction of resistance following treatment with ATRA.     

Down-regulation of CD44 contributes to the differentiation of HL-60 cells induced by ATRA or HMBA

CD44 is highly expressed in human acute myeloid leukemia （AML） cells. Some experiments had shown that it was possible to reverse differentiation blockage in AML cells by CD44 ligation with specific antibodies, indicating that CD44 was closely related to the differentiation of leukemia cells. The differentiation of acute promyelocytic leukemia cell line HL-60 cells could be induced by all trans-retinoic acid （ATRA） and hexamethylene bisacetamide （HMBA）, but so far the mechanism was not demonstrated clearly. In the present study, we investigated whether ATRA or HMBA induced the growth arrest of HL-60 cells by down-regulating the expression of CD44. The results indicated that the proliferation of HL-60 cells was obviously inhibited and the differentiation was induced by both ATRA and HMBA. The decreased expression of CD44 and cyclin E mRNA, and the increased expression of p27 and p21 at mRNA levels were observed. Furthermore, there was a negative correlation between the expression of CD44 and p27. It was concluded that ATRA and HMBA played a role in the differentiation induction of HL-60 cells, which was mediated by the down-regulation of CD44, accompanied by down-regulation of cyclin E, and up-regulation of p27 and p21 mRNA. Cellular ＆ Molecular Immunology. 2007;4（1）：59-63.     

冬凌草甲素对急性白血病HL-60细胞的增殖抑制作用及其作用机制

目的探讨冬凌草甲素对急性白血病HL-60细胞的增殖抑制作用及其作用机制。方法以不同浓度的冬凌草甲素作用于体外培养的HL-60细胞，MTr法检测细胞生长抑制率，应用流式细胞仪检测细胞凋亡情况，瑞氏染色法观察细胞凋亡时的形态学变化。应用PCR．ELISA及RT—PCR法检测细胞凋亡前后端粒酶活性及端粒酶hTERT mRNA表达水平的变化。结果冬凌草甲素可显著的抑制HL-60细胞的生长，诱导细胞发生凋亡，并呈现出明显的量-与时-效关系。冬凌草甲素作用48—60h后在瑞氏染色图片上可见核浓缩及核碎裂等典型的细胞凋亡特征，同时端粒酶hTERT mRNA的表达水平及端粒酶活性均明显降低。结论冬凌草甲素能抑制HL-60细胞的生长及诱导细胞发生凋亡：降低端粒酶hTERT mRNA的表达水平及端粒酶活性可能是其重要作用机制之一。     

Hedgehog信号通路抑制剂GANT61对急性髓系白血病细胞增殖和凋亡的影响

目的:探讨以Gli为靶点的hedgehog信号通路抑制剂GANT61对人急性早幼粒细胞白血病细胞HL-60增殖和凋亡的作用及机制。方法:采用CCK-8法观察不同浓度GANT61对HL-60细胞生长增殖的影响;Annexin V-FITC/PI双染检测GANT61对HL-60细胞凋亡的影响;RT-PCR检测48 h时HL-60细胞中gli1、bcl-2、bcl-xl mRNA表达;免疫荧光检测48 h时HL-60细胞中Gli1蛋白表达。结果:GANT61呈时间和浓度依赖性抑制HL-60细胞增殖;GANT61呈浓度和时间依赖性诱导HL-60细胞凋亡;GANT61呈浓度依赖性抑制gli1、bcl-2、bcl-xl mRNA表达;GANT61呈浓度依赖性抑制Gli1蛋白表达。结论:GANT61通过抑制Hedgehog-gli信号通路进而下调bcl-2和bcl-xl基因的表达,对人急性髓系白血病细胞HL-60起抑制增殖,并诱导其凋亡作用。     

IFN-α和IFN-γ逆转MR2细胞维甲酸耐药的实验研究

目的:探讨IFN-α和IFN-γ与全反式维甲酸(all-trans retinoic acid,ATRA)联合逆转MR2细胞对ATRA耐药的可能性及其机制。方法:IFN-α、IFN-γ及ATRA单独或两种IFN分别与ATRA联合作用于对ATRA耐药的细胞株MR2后,采用MTT比色法检测细胞的增殖,用光镜观察、NBT还原实验及流式细胞仪检测细胞的分化,用间接免疫荧光法检测早幼粒细胞白血病(promyelocytic leukemia,PML)蛋白的表达。结果:两种IFN均能抑制MR2细胞的增殖;IFN与ATRA联合应用时抑制作用更加显著;但两种IFN无论是单独应用还是与ATRA联合应用,二者之间均无统计学意义(P>0.05)。两种IFN也能诱导MR2细胞发生一定程度的分化;二者分别与ATRA联合应用时作用更加显著,但IFN-γ ATRA组诱导MR2细胞分化的作用明显强于IFN-α ATRA组(P<0.05)。两种IFN都能诱导PML蛋白的表达。结论:IFN-γ与ATRA联合应用逆转MR2细胞对ATRA耐药的作用强于IFN-α与ATRA的联合,可能与IFN-α和IFN-γ信号传导途径的不同有关。     

视黄酸对CDK2组成性表达HL—60细胞增殖的影响

探讨细胞周期素依赖性激酶在视黄酸对急性早幼粒细胞白血病ＨＬ－６０细胞的增殖抑制和分化调控过程中的作用。方法应用真核细胞基因转染技术将外源ＣＤＫ２基因转入人ＨＬ－６０早幼粒细胞白血病细胞中,进而以视黄酸处理１－４ｄ。结论ＣＤＫ２在视黄酸诱导的增殖抑制和分化过程中起重要作用,由于ＣＤＫ２的组成性超过表达,导致视黄酸对ＨＬ－６０细胞的增殖抑制和诱导分化作用下降。     

细胞色素C对HL-60细胞促凋亡作用及其对bcl-2、bcl-xl基因表达的影响

目的：探讨细胞色素C在体外作用于HL-60细胞时细胞发生的变化及其相关凋亡基因bcl-2、bcl-xl表达变化的机制。方法:用不同浓度的细胞色素C作用于HL-60细胞24 h，然后用MTT检测细胞色素C对HL-60细胞抑制率；用普通光镜、荧光显微镜检测HL-60细胞形态的变化；用流式细胞仪、DNA凝胶电泳对HL-60细胞凋亡的检测；用RT-PCR检测bcl-2、bcl-xl mRNA表达的变化。结果:细胞抑制率随着细胞色素C浓度的增加而增加；当细胞色素C浓度在0-37.5 mg/L作用HL-60细胞24 h，随着细胞色素C浓度的增加，HL-60细胞发生的凋亡逐渐增加，可见典型的凋亡细胞和明显的DNA梯度条带；同时，在该浓度范围内，bcl-2、bcl-xl mRNA表达逐渐减少；当细胞色素C浓度大于37.5 mg/L时，细胞凋亡率并不增加，而是下降，但是坏死细胞明显增加。结论：一定浓度细胞色素C能诱导HL-60细胞发生凋亡，并且细胞凋亡率、bcl-2、bcl-xl基因表达的变化与细胞色素C浓度呈一定的量效依赖关系，细胞色素C诱导HL-60细胞凋亡可能与抑制bcl-2、bcl-xl基因的表达有一定的关系。     

硫化砷诱导HL-60细胞凋亡中端粒酶活性和hTERT mRNA表达的改变

目的：探讨硫化砷在诱导急性非淋巴细胞白血病(APL)细胞株HL-60凋亡的同时，对端粒酶活性的影响及作用机制。方法：采用PCR—ELISA法测定端粒酶活性；半定量RT—PCR检测hTERT mRNA的表达；流式细胞仪分析细胞周期、细胞凋亡及CD11b表达。结果：用0．3～0．6mg/L的硫化砷作用72h，不能诱导HL-60细胞凋亡，将剂量增至1．5～3．0mg/L时，凋亡细胞的比率逐渐增高，同时伴随HL-60细胞端粒酶活性和hTERT mRNA表达受抑。随着硫化砷浓度的增高，HL—60细胞在G2／M期的比率渐增高。3．0mg/L的硫化砷作用72h，HL-60细胞CD11b的表达由1．27％升至6．07％，结论：硫化砷在诱导HL-60细胞凋亡的同时，下调其端粒酶活性。G2／M期细胞比率的增高可能与端粒酶活性降低相关。高浓度硫化砷72h可轻度诱导HL—60细胞分化。     

达努塞替对HL-60细胞抗肿瘤作用机制的研究

目的:探讨丝氨酸/苏氨酸激酶抑制剂达努塞替对人急性髓细胞白血病(AML)细胞株HL-60的细胞周期阻滞、自噬和凋亡的影响。方法:用MTT法检测达努塞替对HL-60细胞的生长抑制作用;用流式细胞术检测相同时间不同浓度药物组与同一浓度不同时间组的细胞周期、细胞凋亡及细胞自噬;用Western blot方法检测细胞周期相关蛋白CDK1/CDC2、CDK2、cyclin B1、P21Waf1/Cip1、P27Kip1和P53,凋亡相关蛋白Bcl-x L、Bcl-2、Bax、PUMA、cleaved caspase-3及cleaved caspase-9以及自噬相关蛋白p-PI3K、PTEN、p-Akt、p-m TOR、Beclin 1、LC3-I和LC3-II的水平。用共聚焦显微镜检测同时间不同浓度药物组细胞的自噬情况。结果:达努塞替能明显抑制HL-60细胞的活力,诱导细胞周期G2/M期阻滞,可以通过线粒体caspase-3途径诱导细胞凋亡,同时可以通过抑制PI3K/Akt/m TOR信号通路诱导细胞自噬。结论:达努塞替可通过抑制作为染色体伴侣蛋白且在有丝分裂中调控染色质复制与分离的极光激酶A/B有效抑制HL-60细胞生长,引起细胞周期阻滞、凋亡和自噬发生,可能是AML临床治疗具有前景的抗肿瘤靶点。     

黄芩苷对HL-60白血病细胞的诱导分化作用

目的： 观察中药单体黄芩苷(baicalin) 对人髓系白血病（AML）细胞株HL-60细胞的诱导分化作用。方法: 应用细胞形态学方法、细胞克隆形成试验、流式细胞术分析和NBT还原实验检测黄芩苷诱导HL-60细胞分化的能力。结果: 黄芩苷可诱导HL-60细胞向成熟阶段分化，低浓度黄芩苷可显著抑制HL-60细胞克隆的形成；HL-60细胞经黄芩苷处理后CD11b表达显著增高，CD33表达显著降低；NBT还原实验示黄芩苷处理组的分化成熟细胞阳性率明显高于未加药组。结论: 黄芩苷具有诱导HL-60白血病细胞向成熟粒细胞分化的作用。     

Cryopreservation of differentiated HL-60 cells for pyrogen testing

All-trans retinoic-acid (ATRA) differentiated HL-60 cells can be used to detect pyrogens such as bacteria, bacterial components, yeasts and fungi. Differentiated HL-60 cells obtain neutrophil like characteristics and if stimulated the differentiated HL-60 cells produce reactive oxygen species in a dose dependent manner. Culturing and differentiation of cell lines are time consuming activities and require suitable facilities; cryopreservation of pre-differentiated cells could provide the basis for an easily distributable pyrogen testing kit. Cryopreservation of granulocytes has proven to be very complicated and neutrophils are especially difficult to cryopreserve, most likely due to their large degree of granulation. Here we present evidence that HL-60 cells can be differentiated with ATRA and subsequently cryopreserved. Upon thawing the cells retain their ROS producing capabilities and reactivity towards pyrogens. Further, the cells retain their ability to react dose dependently towards lipopolysaccharide (LPS), lipoteichoic acid (LTA) and zymosan. At pathophysiologically relevant concentrations of LPS, LTA and zymosan the cells retain full reactivity for at least two months when stored in liquid nitrogen. In conclusion, ATRA differentiated HL-60 cells are cryopreservable and retain reactivity upon thawing. It is therefore possible to produce an in-vitro in-house pyrogen test kit for medicines and related products.     

白血病细胞TGF-β1含量减少及外源性TGF-β1基因对HL-60细胞的作用

目的：研究白血病细胞是否存在转化生长因子β1（TGF-β1）量的异常以及这种异常在白血病发病机制中的可能作用。 方法： 应用ELISA法检测白血病细胞株和原代白血病细胞培养上清TGF-β1水平，进一步应用脂质体介导基因转移法将TGF-β1基因转染HL-60细胞，采用有限稀释法及G418筛选得到抗性细胞，应用RT-PCR、白血病细胞集落培养、裸鼠移植瘤成瘤试验、片段化DNA分析、流式细胞术检测HL-60细胞内TGF-β1、bcl-2、端粒酶反转录酶（hTERT）mRNA的表达变化等方法了解外源性TGF-β1基因对HL-60细胞体内外增殖、凋亡的影响。 结果： 白血病细胞株和原代白血病细胞培养上清TGF-β1水平明显低于正常对照组(P<0.01)，转染TGF-β1基因后，HL-60细胞内TGF-β1 mRNA表达上调，bcl-2、hTERT mRNA表达下调，细胞体外增殖受抑制，集落形成抑制率达78.3%，裸鼠移植瘤生长受抑制，荷瘤鼠生存期延长，细胞呈现凋亡特征性的梯形条带，凋亡比例达73.4%。 结论： 内源性TGF-β1水平降低是白血病的发病机制之一,外源性TGF-β1基因能够抑制HL-60细胞增殖，诱导细胞凋亡,该基因通过下调bcl-2、hTERT mRNA的表达而发挥作用。     

Changes in susceptibility to Fas-mediated apoptosis during differentiation of HL-60 cells

The Fas-mediated pathway has been implicated as an important cellular pathway mediating apoptosis in diverse cell types. We conducted studies to examine the susceptibility to Fas-mediated apoptosis of HL-60 cells treated with differentiation-inducing factors such as dimethyl sulfoxide (DMSO), retinoic acid (RA), and 1alpha, 25 dihydroxyvitamin D3 (VD3). Although the expression of Fas antigen (Ag) and its mRNA showed a marked increase in HL-60 cells with cell differentiation, that of Bcl-2 protein and its mRNA revealed the reverse. The expression of caspase proteins such as caspases-3 and -8 was also enhanced during cell differentiation. DNA fragmentation, annexin V binding, and caspase activities increased in differentiated HL-60 cells with the addition of anti-Fas Ag antibody. These findings were more clearly demonstrated in DMSO- or RA-induced neutrophil-like cells than in VD3-induced monocyte-like cells. Therefore, susceptibility to Fas-mediated apoptosis showed an increase with differentiation of HL-60 cells, especially in the neutrophil lineage. These results suggest that the difference of susceptibility to Fas-mediated apoptosis among cell populations depends on the expression of Fas Ag, Bcl-2, and caspases. Cell maturation and susceptibility to Fas-mediated apoptosis may be linked in hematopoietic cells.     

SU11248对白血病细胞HL-60增殖及凋亡作用的实验研究

目的:探讨新型抗肿瘤药物苹果酸舒尼替尼(SU11248)对白血病细胞HL-60的生物学效应的影响及其作用机制。方法:应用MTT法检测SU11248对HL-60细胞增殖能力的影响;用AnnexinV/PI双染流式细胞术检测细胞凋亡;用流式细胞技术分析细胞的DNA倍体及细胞周期变化;用凝胶电泳分析DNA片段化;以Western blot法检测2.0μg/ml SU11248作用HL-60后bcl-2、bax、caspase-3蛋白水平的变化。结果:SU11248可明显抑制HL-60细胞增殖(P<0.05),呈剂量和时间依赖性,半数抑制浓度(IC50)约为2.00μg/ml。SU11248可促进细胞凋亡,并呈剂量依赖性;能将HL-60细胞阻滞于G0/G1期,并呈时间依赖性;诱导HL-60细胞呈典型的DNA梯带;SU11248作用后bcl-2蛋白表达随时间依赖性降低,caspase-3蛋白表达升高,bax蛋白表达无明显变化。结论:SU11248能抑制HL-60细胞增殖,诱导其凋亡,调节bcl-2家族蛋白的表达,并裂解caspase-3是其可能作用机制之一。     

脂质体转染细胞周期素B1反义脱氧寡核苷酸对HL60细胞增殖调控的影响

目的:探讨脂质体转染细胞周期素B1(cyclinB1)反义脱氧寡核苷酸(ASON)对HL60细胞增殖调控的作用。方法:用针对cyclinB1mRNA5’端编码区起始密码子(ATG/AUG)的ASON,通过脂质体导入HL60细胞共培养后,用流式细胞术(FCM)和RT-PCR分别检测cyclinB1蛋白和mRNA的表达水平,电镜和原位细胞凋亡检测法(POD)、FCM及DNA凝胶电泳法检测细胞凋亡。结果:CyclinB1ASON组与SON及空白对照组相比,ASON能特异地抑制cyclinB1蛋白及mRNA水平的表达,当ASON的浓度达到一定程度时,HL60细胞的增殖及集落形成率均明显受抑制,出现细胞凋亡,并且此作用随ASON浓度的升高而增强。结论:CyclinB1的特异ASON能封闭其蛋白及mRNA的表达水平,可剂量依赖性地抑制白血病细胞增殖,诱导细胞凋亡。