Effects of Betulinic Acid on Proliferation and Apoptosis in Jurkat Cells and Its In Vitro Mechanism

The anti-cancer effects of betulinic acid （BA） on Jurkat cells and its in vitro mechanism were examined by using MTT assay. Apoptosis was detected by using Hoechst33258 staining and annexin-Ⅴ/PI double-labeled cytometry. The effects of betulinic acid on the cell cycle of Jurkat cells were studied by propidium iodide method. RT-PCR and Western blotting were used to analyze the changes of cyclin D3, bcl-xl mRNA and protein levels in Jurkat cells after treatment with betulinic acid. Our results showed the proliferation of Jurkat cells was decreased in betulinic acid-treated group with a 24-h IC50 value being 70.00 μmol/L. Betulinic acid induced apoptosis of Jurkat cells in a time-and dose-dependent manner. The number of Jurkat cells treated with betulinic acid showed an increase in G0/G1 phase and decrease in S phase. After treatment with 0, 20, 60, 100 μmol/L betulinic acid for 24 h, the number of Jurkat cells was increased from （31.00±1.25）% to （58.84±0.32）% in G0/G1 phase, whereas it was decreased from （61.45±1.04）% to （35.82±1.95）% in S phase. PBMCs were less sensitive to the cytotoxicity of betulinic acid than Jurkat cells. The expressions of cyclin D3, bcl-xl mRNA and protein were decreased sharply in Jurkat cells treated with betulinic acid. It is concluded that betulinic acid is able to inhibit the proliferation of Jurkat cells by regulating the cell cycle, arrest cells at G0/G1 phase and induce the cell apoptosis. The anti-tumor effects of betulinic acid are related to the down-regulated expression of cyclin D3 and bcl-xl.

Down-regulation of β-catenin Nuclear Localization by Aspirin Correlates with Growth Inhibition of Jurkat Cell Line

In this study, we examined the effects of aspirin on the growth rates, subcellar distribution of β-catenin protein, the expression of β-catenin/TCF signaling pathway target gene cyclinD1 mRNA, and cell cycle of Jurkat cell line （Human T-acute lymphoblastic leukemia）. Our results showed that the treatment with aspirin inhibited the growth of Jurkat cell line. Jurkat cells treated with 3 mmol/L of aspirin could significantly decrease nuclear localization of β-catenin, and at 5 mmol/L of aspirin, the nuclear localization of β-catenin was undetectable. QRT-PCR showed that the target gene cyclinDl mRNA expression was gradually decreased with the dosage of aspirin. Aspirin induced G0/G1 cell cycle arrest in Jurkat cells. We are led to conclude that aspirin acts through β-catenin-independent mechanisms. The effects of aspirin include down-regulation of β-catenin nuclear localization and G0/G1 cell cycle arrest, which might serve as a means of growth inhibition in aspirin-treated human Jurkat cell line.

Induction of Apoptosis by Recombinant Soluble Human TRAIL in Jurkat Cells

Objective To investigate the therapeutic potential of tumor necrosis factor （TNF）-related apoptosis-inducing ligand （TRAIL）, a member of the TNF superfamily, and to analyze TRAIL-induced apoptosis in Jurkat cells. Methods Expression of TRAIL receptors （DR4 and DR5） was detected by reverse transcriptase-polymerase chain reaction （RT-PCR）. Cytotoxic effects were determined by colony formation assay and a cell counting kit. The effects of recombinant TRAIL on apoptosis of Jurkat cells were determined by DNA fragmentation （DNA ladder） and PI staining. Changes in mitochondrial membrane potential were detected with JC-1 fluorescence. Results TRAIL inhibited the proliferation and induced intemucleosomal DNA fragmentation （characteristic of apoptosis） and loss of mitochondrial membrane potential. Conclusion Recombinant soluble TRAIL can be used as a therapy for cancer.

The associated regulators and signal pathway in rIL-16/CD4 mediated growth regulation in Jurkat cells

IL-16 is a ligand and chemotactic factor for CD4+ T cells. IL-16 inhibits the CDS mediated lymphocyte activation and proliferation. The effects of IL-16 on the target cells are dependent on the cell type, the presence of co-activators etc. To understand the regulation function and mechanism of IL-16 on target cells, we used a 130 a.a. recombinant IL-16 to study its effects on the growth of Jurkat T leukemia cells in vitro. We found that the rIL-16 stimulated the proliferation of Jurkat cells at low dose (10-9M), but inhibited the growth of the cells at higher concentration (10-5M). Results showed that 10-5 M of rIL-16 treatment induced an enhanced apoptosis in Jurkat cells. The treatment blocked the expression of FasL, but up-regulated the c-myc and Bid expression in the cells. Pre-treatment of PKC inhibitor or MEK1 inhibitor markedly increased or decreased the rIL-16 induced growth-inhibiting effects on Jurkat cells, respectively. The results suggested that the rIL-16 might be a regulator for the growth or apoptosis of Jurkat cells at a dose-dependent manner. The growth-inhibiting effects of rIL-16 might be Fas/FasL independent, but, associated with the activation of PKC, up-regulated expression of c-Myc and Bid, and the participation of the ERK signal pathway in Jurkat cells.

Down-regulation of Bmi-1 by RNA interference in Jurkat cells

Objective： The aim of our study was to investigate the effects of down-regulation Bmi-1 by RNA interference （RNAi） in T Lymphocytic leukemia Jurkat cells. Methods： Two complementary oligonucleotide strands were synthesized based on the siRNA sequence targeting Bmi-1 gene. After annealing, siRNA strands were recombined into the pRNAT- U6.2 vector, and then DNA sequencing was carded out following transformation and amplification. The recombinant was transfected into Jurkat cells with liposomes. Positive colonies were obtained through G418 selection. The mRNA and protein expressions of Bmi-1 were detected by RT-PCR and Western-blot, respectively. Effects of Bmi-1 silence on cell proliferation, cell cycle and cell aging of Jurkat cells were detected by M＇l-r assay, flow cytometry, colony formation assay and SA-β-Gal staining, respectively. Results： The siRNA recombinant targeting Bmi.1 gene was successfully constructed. All three siRNA recombinants could significantly inhibit the expression of Bmi-l. The siRNA targeting 825nt-843nt （GACCAGACCACTACT GAAT） has the strongest inhibitory effect on Bmi-1 expression, with almost complete inhibition on Bmi-1 mRNA and protein expressions. Compared with the non-transfection group and the empty vector group, growth velocity and colony formation ability were significantly decreased, while the proportion of calls in G1 phase and the percentage of senile cells were signifi- cantly increased in highly transfected group （P 〈 0.05）. Conclusion： Down-regulation Bmi-1 by RNA interference （RNAi） could significantly inhibit the growth of Jurkat cells in vitro.

Inhibition of the α-mannosidase Man2c1 gene expression enhances adhesion of Jurkat cells

Protein N-glycosylation plays very important roles in immunity and α-mannosidase is one of the key enzymes in Nglycosylation. This paper reports that inhibition of α-mannosidase Man2c1 gene expression enhances adhesion of Jurkat T cells. In comparison to the controls with normal expression of the enzyme, Jurkat cells with the inhibition of Man2c1 gene expression （AS cell） formed larger aggregates in culture, indicating an enhancement of adhesion between the cells. mRNA differential display analysis discovered up-regulation of several adhesion molecule genes in the AS cell. Because of the pivotal role played by CD54-LFA-1 interaction in immune cell interaction, this study focused on the contribution of enhanced expression of CD54 and LFA-1 to the enhanced adhesion of AS Jurkat cells. These facts, including increased binding of AS cells to ICAM-1-Fc, Mg^2＋ activation of the binding of AS cells to ICAM-1-Fc and enhanced aggregation of AS cells, together with the inhibiting effect of a blocking CD1 la mAb on the binding to ICAM-1-Fc and aggregation of the cells demonstrate an important contribution of enhanced CD54-LFA-1 interaction to increased adhesion between AS cells. The enhanced CD54-LFA-1 interaction also resulted in increased adhesion between AS Jurkat T cells and Raji B cells. In addition, AS cells showed cytoskeletal rearrangement. The data imply a biological significance of MAN2C1 in T-cell functioning.

CAHB诱导成人急性淋巴细胞白血病Jurkat细胞凋亡机制的研究

目的 探讨二乙酰己二胺(diacetyl hexamethylene diamine,CAHB)诱导成人急性淋巴细胞白血病Jurkat细胞凋亡的机制,为CAHB应用于临床提供理论依据。方法 采用流式细胞仪分析CAHB处理后Jurkat细胞AnnexinⅤ^(+)/PI^(-)细胞率,观察应用胱天蛋白酶(caspase)-9抑制剂Z-LEHD-FMK处理后AnnexinⅤ^(+)/PI^(-)细胞率的变化;蛋白质印迹法观察凋亡相关蛋白caspase-8、caspase-9、caspase-3的表达变化。结果 CAHB诱导后Jurkat细胞体积缩小、胞膜皱缩、染色质浓染、核固缩或碎裂等,可见典型凋亡小体。CAHB通过激活caspase-9、caspase-3诱导Jurkat细胞发生凋亡,其作用呈明显的量效关系和时间依赖性,caspase-9抑制剂可在一定程度上抑制CAHB的凋亡诱导作用。结论 CAHB诱导Jurkat细胞凋亡与激活caspase-9及caspase-3有关。

miRNA-106a在人淋巴瘤Jurkat细胞中的表达及作用机制

目的探讨miRNA-106a在人淋巴瘤Jurkat细胞中的表达及作用机制。方法取对数生长期人淋巴瘤Jurkat细胞,分别向培养基中加入5 ml生理盐水配制的浓度为0、0.5、1.0、1.5μg/ml的多柔比星,取健康体检者(对照组)的单个核细胞。采用定量逆转录聚合酶链反应(qRT-PCR)检测miRNA-106a以及视网膜母细胞瘤1(RB1)、E2F转录因子1(E2F1)、胱天蛋白酶3(caspase 3)mRNA的表达水平,采用噻唑蓝(MTT)法检测细胞增殖能力,流式细胞术检测细胞凋亡能力,采用蛋白质印迹法(Western blot)检测RB1、E2F1、caspase 3蛋白的表达水平。结果0μg/ml多柔比星干预人淋巴瘤Jurkat细胞miRNA-106a的表达水平明显高于对照组单个核细胞(P﹤0.01)。随多柔比星浓度升高、作用时间延长,miRNA-106a表达水平逐渐降低,光密度(OD)值逐渐降低,细胞增殖抑制率(IR)和凋亡率均逐渐升高,RB1、caspase 3 mRNA及其蛋白的表达水平均逐渐升高,E2F1 mRNA及其蛋白的表达水平均逐渐降低,差异均有统计学意义(P﹤0.05)。相关性分析结果显示,miRNA-106a与RB1、caspase 3的表达均呈负相关(P﹤0.01),与E2F1的表达呈正相关(P﹤0.01)。结论miRNA-106a在人淋巴瘤Jurkat细胞中高表达,其可能通过调控RB/E2F1通路相关蛋白的表达来调节淋巴瘤进展。

靶向沉默Ku80对T-ALL细胞系Jurkat化疗敏感性影响的初步研究

目的:探讨靶向沉默Ku80对T-ALL细胞系Jurkat化疗敏感性的影响以及潜在机制。方法:通过RT-qPCR及Western blot技术检测6种不同血液肿瘤细胞系中Ku80基因的转录与表达水平;设计并构建Ku80特异性shRNA干扰质粒并转染T-ALL细胞系Jurkat后检测Ku80蛋白表达;CCK-8技术检测Ku80沉默后Jurkat细胞的增殖能力;软琼脂克隆形成技术、流式细胞术及Western blot技术分别检测Ku80沉默协同化疗药物依托泊苷(VP16)处理细胞4 h后Jurkat细胞的克隆形成能力、凋亡水平及DNA损伤蛋白γH2AX的表达水平。结果:在选取的6种不同血液肿瘤细胞系中,T-ALL细胞系Jurkat中Ku80的mRNA及蛋白水平均最高。构建的shRNA质粒成功靶向沉默了Jurkat细胞中Ku80的表达。Ku80靶向沉默后Jurkat细胞增殖能力明显下降(P<0.05);VP16孵育前后,Ku80靶向沉默均可显著降低Jurkat细胞克隆形成能力(P<0.01)、提高Jurkat细胞凋亡水平(P<0.01),并且γH2AX的表达水平显著提高(P<0.05)。结论:靶向沉默Ku80表达可增强T-ALL细胞系Jurkat对化疗药物VP16的敏感性,这或与其造成的DNA损伤积累水平增加有关。

Bcl-2 over-expression and activation of protein kinase C suppress the Trail-induced apoptosis in Jurkat T cells

Trail, a tumor necrosis factor-related apoptosis-inducing ligand, is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2. Its role, like FasL in activation-induced cell death (AICD), has been demonstrated in immune system. However the mechanism of Trail induced apoptosis remains unclear. In this report, the recombinant Trail protein was expressed and purified. The apoptosis-inducing activity and the regulation mechanism of recombinant Trail on Jurkat T cells were explored in vitro. Trypan blue exclusion assay demonstrated that the recombinant Trail protein actively killed Jurkat T cells in a dose-dependent manner. Trail-induced apoptosis in Jurkat T cells were remarkably reduced by Bcl-2 over expression in Bcl-2 gene transfected cells. Treatment with PMA (phorbol 12-myristate 13-acetate), a PKC activator, suppressed Trail-induced apoptosis in Jurkat T cells. The inhibition of apoptosis by PMA was abolished by pretreatment with Bis, a PKC inhibitor. Taken together, it was suggested that Bcl-2 over-expression and PMA activated PKC actively down-regulated the Trail-mediated apoptosis in Jurkat T cell.

Role of the Ca^2＋-Calcineurin-Nuclear Factor of Activated T cell Pathway in Mitofusin-2-Mediated Immune Function of Jurkat Cells

Background：Mitofusin-2 （MFN2）,a well-known mitochondrial fusion protein,has been shown to participate in innate immunity,but its role in mediating adaptive immunity remains poorly characterized.In this study,we explored the potential role of MFN2 in mediating the immune function of T lymphocytes.Methods：We manipulated MFN2 gone expression in Jurkat cells via lentiviral transduction of MFN2 small interfering RNA （siRNA） or full-length MFN2.After transduction,the immune response and its underlying mechanism were determined in Jurkat cells.One-way analysis of variance and Student＇s t-test were performed to determine the statistical significance between the groups.Results：Overexpression of MFN2 enhanced the immune response of T lymphocytes by upregulating Ca2＋ （359.280 ± 10.130 vs.266.940 ± 10.170,P =0.000）,calcineurin （0.513 ± 0.014 vs.0.403 ± 0.020 nmol/L,P =0.024）,and nuclear factor of activated T cells （NFATs） activation （1.040 ± 0.086 vs.0.700 ± 0.115,P =0.005）,whereas depletion of MFN2 impaired the immune function ofT lymphocytes by downregulating Ca2＋ （141.140 ± 14.670 vs.267.060 ± 9.230,P =0.000）,calcineurin （0.054 ± 0.030 nmol/L vs.0.404 ± 0.063 nmol/L,P =0.000）,and NFAT activation （0.500 ± 0.025 vs.0.720 ± 0.061,P =0.012）.Furthermore,upregulated calcineurin partially reversed the negative effects ofMFN2 siRNA on T cell-mediated immunity evidenced by elevations in T cell proliferation （1.120 ± 0.048 vs.0.580 ± 0.078,P =0.040）,interleukin-2 （IL-2） production （473.300 ± 24.100 vs.175.330 ± 12.900 pg/ml,P =0.000）,and the interferon-γ/IL-4 ratio （3.080 ± 0.156 vs.0.953 ± 0.093,P =0.000）.Meanwhile,calcineurin activity inhibitor depleted the positive effects of overexpressed MFN2 on T cells function.Conclusions：Our findings suggest that MFN2 may regulate T cell immune functions primarily through the Ca2＋-calcineurin-NFAT pathway.MFN2 may represent a potential therapeutic target for T cell immune dysfunction-related diseases.

The effects and mechanism of action of Prunella vulgaris L extract on Jurkat human T lymphoma cell proliferation

Objective:The aim of this study was to observe the effect of the Prunella vulgaris L extract on the Jurkat human T lymphoma cell line.Methods:Jurkat cells were cultivated with different concentrations of the extract from Prunella vulgaris L.The MTT assay and flow cytometry were employed to determine the cells' proliferation inhibition ratio and the apoptosis rates,respectively.Agarose gel electrophoresis was used to observe cellular DNA fragmentation,and western blotting was used to observe changes in Bcl-2 and Bax protein expression.Results:The Prunella vulgaris L extract remarkably inhibited the proliferation of Jurkat cells.This inhibition exhibited dose dependence,with an IC50 of 20.23 ± 0.31 μg/mL.Agarose gel electrophoresis showed that the apoptosis strap became wider and brighter,and flow cytometry showed that the apoptosis rate increased in a concentration-dependent manner.Western blotting showed that Bcl-2 protein was down-regulated and Bax protein was up-regulated during apoptosis.Conclusion:The extract from Prunella vulgaris L induced apoptosis of Jurkat cells by down-regulating Bcl-2 protein and up-regulating Bax protein.These actions inhibited the growth of Jurkat cells.

Systemic Nuclear Proteomics Researches on Change of Jurkat T Lymphocyte Cells Under Radiation

Radiation causes severe constraint on numerous pathological functions of cells, such as cell growth, nuclear genetic material expression and cell functions. In this study, we performed proteomic profiling of a nuclear fraction of Jurkat T lymphocyte cells under radiation along different time course by means of 2DE and MALDI TOF-MS. We found 24 protein spots whose expression had changed after radiation, including relevant proteins, genetic material proteins, metabolism proteins, molecular chaperon and nuclear membrane proteins. Based on the above it is concluded that the combination of fluorescence labeled 2D-PAGE and MALDI-TOF MS is more precisely and effectively to elucidate the protein changes in Jurkat T lymphocyte cells after irradiation.

中度寻常性银屑病患者血浆对Jurkat细胞作用的研究

目的:探究中度寻常性银屑病患者血浆微环境对Jurkat细胞炎症因子分泌、增殖及凋亡活性的影响。方法:分别采用中度寻常性银屑病患者(试验组)和正常人(对照组)的血浆培养Jurkat细胞,48 h后采用实时荧光定量聚合酶链式反应(RTqPCR)检测Jurkat细胞分泌白细胞介素(IL)-8、IL-10、增殖核抗原(Ki-67)、细胞死亡受体1(Fas)、Fas配体(FasL)、胱天蛋白酶(Caspase)-3及Caspase-8的mRNA相对表达水平。结果:RT-qPCR结果显示与对照组相比,试验组Jurkat细胞表达促炎因子IL-8水平增高,抑炎因子IL-10水平降低(P<0.05);Fas、FasL、Caspase-3及Caspase-8表达水平均显著上调(P<0.05);而Ki-67表达差异无统计学意义(P>0.05)。Spearman相关性分析显示,试验组中高表达的IL-8水平与胞内Fas(r=0.72,P<0.05)、FasL(r=0.54,P<0.05)、Caspase-3(r=0.62,P<0.05)、Caspase-8(r=0.69,P<0.05)mRNA表达均呈正相关;低表达的IL-10水平与胞内Fas(r=-0.40,P<0.05)、Caspase-3(r=-0.46,P<0.05)、Caspase-8(r=-0.62,P<0.05)mRNA表达均呈负相关。结论:银屑病患者血浆可诱导Jurkat细胞IL-8及IL-10表达异常,并增强Fas/FasL凋亡途径;且IL-8与Fas/FasL凋亡呈正相关,IL-10与Fas/FasL凋亡呈负相关,提示银屑病血浆微环境异常可能是T细胞活性异常的形成机制之一。

徐长卿中的天然产物XCQ-9对Jurkat细胞增殖和凋亡的影响及机制研究

目的探讨徐长卿中天然产物XCQ-9抑制人急性T淋巴细胞白血病Jurkat细胞增殖和凋亡的作用及可能机制。方法以Jurkat细胞作为白血病细胞模型,采用MTT法测定0(空白对照)、2.5、5、10、20、40μmol/L XCQ-9作用24、48、72 h后对Jurkat细胞增殖的抑制作用。用0(空白对照)、2.5、5、10μmol/L XCQ-9作用于Jurkat细胞24、48 h后,利用流式细胞术分析XCQ-9对细胞周期和细胞凋亡的影响,并通过Western blot实验检测上述药物作用24 h后细胞中胱天蛋白酶9(Caspase-9)、活化的Caspase-9(Cleaved Caspase-9)、Caspase-3、活化的Caspase-3(Cleaved Caspase-3)、聚腺苷二磷酸-核糖聚合酶(PARP)、活化的PARP(Cleaved PARP)、细胞周期蛋白依赖性激酶1(CDK1)和细胞周期蛋白B1(Cyclin B1)的表达情况。结果与空白对照比较,不同浓度XCQ-9均可显著降低Jurkat细胞的存活率(P<0.01),并呈时间和浓度依赖性趋势。5、10μmol/L XCQ-9作用48 h后均可显著诱导Jurkat细胞凋亡(P<0.05或P<0.01),将细胞周期阻滞在G2期(P<0.01)。10μmol/L XCQ-9作用24 h后,可显著下调细胞中CDK1、Caspase-9蛋白的表达(P<0.01),上调细胞中Cyclin B1、Cleaved Caspase-9、Cleaved Caspase-3和Cleaved PARP蛋白的表达(P<0.05或P<0.01)。结论XCQ-9通过诱导G2期阻滞抑制Jurkat细胞增殖,并激活Caspase通路促进细胞凋亡,从而发挥其抗肿瘤作用。

异藤黄酚对急性淋巴细胞白血病Jurkat细胞增殖和凋亡的影响及机制

目的探讨异藤黄酚(ISO)对急性淋巴细胞白血病(ALL)Jurkat细胞增殖和凋亡的影响及机制。方法人ALL Jurkat细胞和人正常肝细胞HL-7702分别培养至对数生长期,0[二甲基亚砜(DMSO)]、10、15、20及25μmol/L ISO处理2种细胞,采用噻唑蓝(MTT)法检测各组细胞处理后24、48及72 h的光密度(OD)并计算细胞存活率;取对数生长期Jurkat细胞,分别用0(DMSO)、10、15及20μmol/L ISO处理,采用流式细胞术检测各浓度ISO组Jurkat细胞24、48 h的凋亡率,采用Hoechst 33258染色法验证各浓度ISO组Jurkat细胞24 h的凋亡率,采用线粒体膜电位(MMP)检测试剂盒(JC-1)检测各浓度ISO组Jurkat细胞24 h的MMP,采用RNA高通量测序(RNA-seq)分析ISO组Jurkat细胞24 h的细胞内基因转录水平,采用Western blot检测各浓度ISO组Jurkat细胞24 h时凋亡相关蛋白半胱氨酸天冬氨酸蛋白酶3(Caspase3)、半胱氨酸天冬氨酸蛋白酶9(Caspase9)、剪切的Caspase3(Cleaved-caspase3)、剪切的Caspase9(Cleaved-caspase9)、凋亡蛋白酶活化因子-1(Apaf-1)、细胞色素C(Cytc)、蛋白激酶B(Akt)、磷脂酰肌醇-3-激酶(PI3K)、磷酸化PI3K(p-PI3K)、重组人BH3结构域凋亡诱导蛋白(Bid)、截断的Bid(t-Bid)、磷酸化的信号转导和转录激活因子-3(p-STAT3)、Janus激酶2(JAK2)、磷酸化JAK2(p-JAK2)、多聚腺苷二磷酸核糖聚合酶(PARP)、剪切的PARP(Cleaved-PARP)、丝裂原活化蛋白激酶p38(p38)蛋白的表达。结果MTT检测结果显示,与DMSO组相比,10、15、20及25μmol/L ISO组Jurkat细胞活力下降(P<0.05),且具有时间依赖性;流式细胞术结果显示,与DMSO组相比,10、15及20μmol/L ISO组Jurkat细胞凋亡率升高(P<0.05),且具有时间依赖性;Western blot结果显示,与DMSO组相比,10、15及20μmol/L ISO处理Jurkat细胞24 h后,Cleaved-caspase3、Cleaved-caspase9、Cleaved-PARP、t-Bid、Apaf-1及Cytc的表达上调(P<0.05),p-JAK2、p-STAT3及c-Myc的表达下调(P<0.05);RNAseq分析结果,与DMSO组相比,15μmol/L ISO处理Jurkat细胞24 h后,299个基因上调、57个基因下调,且主要影响了Jurkat细胞中MAPK及PI3K/Akt等信号途径,进一步细胞实验结果表明,与DMSO组相比,10、15及20μmol/L ISO组Jurkat细胞中p-p38的表达上调(P<0.05),p-PI3K、p-Akt的表达下调(P<0.05)。结论ISO可抑制Jurkat细胞增殖、诱导细胞凋亡,其机制可能与抑制JAK2/STAT3/c-Myc、PI3K/Akt信号通路及激活p38 MAPK信号通路有关。

雷公藤红素对白血病HL-60和Jurkat细胞增殖及凋亡的影响

探讨雷公藤红素对人急性髓性白血病HL-60细胞、急性T淋巴细胞白血病Jurkat细胞增殖及凋亡的影响。采用MTT法、Annexin V-FITC/PI双染法、PI染色法、透射电镜观察不同浓度雷公藤红素作用于两种细胞后对其生长增殖、凋亡、周期及形态等方面的影响。结果表明雷公藤红素能显著抑制HL-60细胞、Jurkat细胞的增殖,降低其存活率。给药24 h后,半抑制浓度(IC50)分别为(0.46±1.05)μmol/L和(0.88±1.13)μmol/L。以剂量依赖方式诱导两种细胞凋亡,细胞周期分布G1期比例增加,S期比例降低(P<0.05),且伴有典型的细胞凋亡形态学改变。雷公藤红素能显著抑制HL-60细胞、Jurkat细胞的生长增殖,并诱导细胞凋亡。

几种不同方式诱导Jurkat细胞凋亡过程中TFAR19的表达

为探讨一个新的细胞凋亡相关基因———TFAR19所参与的凋亡途径 ,我们研究了几种不同方式诱导白血病细胞株Jurkat细胞凋亡过程中TFAR19表达的变化。采用去除血清 ,VP 16作用及Fas单抗活化受体等方法诱导Jurkat细胞凋亡后 ,以RT PCR方法检测mRNA水平TFAR19的表达 ,用流式细胞术及Western印迹检测蛋白水平TFAR19的表达。实验结果显示 ,Jurkat细胞在去除血清 12小时 ,VP 16作用 2小时 ,以及Fas单抗诱导细胞凋亡 2小时后 ,在mRNA及蛋白水平TFAR19的表达都呈增高趋势。结论提示 ,TFAR19参与了去除血清、DNA损伤及死亡受体激活所诱导的细胞凋亡过程 ,它在细胞凋亡过程的早期开始发挥作用 ,TFAR19是细胞凋亡途径中的“终末共同通路”的参与者。

通关藤提取物体外对Jurkat、Raji、RPMI8226细胞的抑制作用研究

目的探讨通关藤提取物对Jurkat、Raji、RPMI8226细胞的抑制作用及可能机制。方法以不同浓度通关藤提取物处理Jurkat、Raji、RPMI8226细胞,MTT法检测其对3种细胞的抑制作用,Annexin V/PI双染法观察细胞形态并检测细胞的凋亡率,JC-1染色法检测细胞线粒体跨膜电位(ΔΨm)水平。结果通关藤提取物对Jurkat细胞的抑制作用最强,对RPMI8226细胞最不敏感。25,50μL/mL的通关藤提取物能降低Jurkat、Raji细胞内ΔΨm,并促进其凋亡。100μL/mL的通关藤提取物也可降低RPMI8226细胞ΔΨm而诱导其凋亡。结论通关藤提取物体外对部分淋巴细胞白血病细胞株和骨髓瘤细胞株有不同程度的诱导凋亡作用,可能是通过降低ΔΨm途径触发这些细胞凋亡。

雷公藤甲素对急性T淋巴细胞白血病Jurkat细胞增殖和凋亡的影响

为了研究雷公藤甲素对急性T淋巴细胞白血病Jurkat细胞的增殖和凋亡效应,用不同浓度的雷公藤甲素作用于Jurkat细胞,用CCK法检测细胞存活率,选取使细胞增殖抑制率为50%的雷公藤甲素作用于细胞,然后在应用Hoechst 33258染色、DNA电泳、PI以及PI/Annexin V染色后用流式细胞仪检测细胞的凋亡。结果表明:雷公藤甲素抑制Jurkat细胞的生长增殖,半数细胞抑制剂量为4μg/L。4μg/L雷公藤甲素作用于Jurkat细胞12小时后,出现明显的细胞凋亡特征(Hoechest 33258染色显示细胞核呈亮蓝色;DNA断裂产生DNA ladder,细胞凋亡的亚二倍体峰出现,细胞磷脂酰丝氨酸发生转位),细胞凋亡比率明显增加,24小时后细胞凋亡进一步增加。结论:雷公藤甲素对急性T淋巴细胞白血病Jurkat细胞有明显的抗增殖和促凋亡作用,这为临床应用雷公藤甲素治疗白血病提供了实验依据。