熊去氧胆酸选择性诱导人肝肿瘤细胞凋亡及抑制增殖的实验研究

目的: 探讨熊去氧胆酸 (UDCA)对肝肿瘤细胞株诱导凋亡及抑制增殖的作用和机制。方法:用四氮唑蓝法、流式细胞术、TUNEL法、Wright Giemsa染色法、电镜及免疫细胞化学等方法,观察UDCA对肝肿瘤细胞株HepG2,BEL7402和正常人肝细胞株L 02的生长活力、细胞凋亡、细胞周期及Bax/bcl 2表达的影响。结果: UDCA对HepG2,BEL7402细胞株生长的抑制作用随药物浓度增高而增强(r2 =0. 96, P<0. 01;r2 =0. 97, P<0. 01;48h)。UDCA对HepG2及BEL7402的IC50分别为0. 92 mmol·L-1, 0. 86 mmol·L-1。UDCA(1. 0mmol·L-1 )对HepG2及BEL7402的凋亡率分别为(42±6) %及 (44±4) %,明显高于对照组(P<0. 01),并且阻滞细胞周期于S期。以UDCA(0. 8mmol·L-1 )处理HepG2 后bcl 2 表达由(24. 3±2. 4) %降低为 (10. 1±1. 6 ) %,Bax表达由(43±5) %升高为 (59±3) % (P<0. 01 );处理BEL7402细胞后bcl 2表达由 (21. 6±1. 8) %降为(11. 6±2. 1) %,Bax表达由 ( 44±4 ) %升高为(59±3) % (P<0. 01)。UDCA对L 02细胞无明显作用。结论: UDCA对HepG2, BEL7402细胞株有显著的抑制增殖及诱导凋亡作用,它可能与UDCA阻滞细胞周期、降低bcl 2和提升Bax的表达有关。     

葫芦素E通过诱导G_2/M周期阻滞抑制人肝癌细胞增殖

目的研究葫芦素E(cucurbitacin E,CuE)体外对人肝癌BEL7402和HepG2细胞的增殖抑制作用及机制。方法MTT法检测不同浓度CuE体外对BEL7402和HepG2细胞的增殖抑制作用;流式细胞仪检测CuE对细胞周期分布的影响;Western blot法检测CuE对细胞周期调节蛋白cy-clinB1、Cdc25C、Cdk1及p21表达的影响。结果CuE作用72 h可剂量依赖性地抑制BEL7402和HepG2细胞增殖;CuE(100 nmo.lL-1)作用12、24 h后可使BEL7402和HepG2细胞周期阻滞于G2/M期,并可下调Cdk1蛋白的表达,上调p21蛋白的表达。结论CuE体外可抑制人肝癌BEL7402和HepG2细胞的增殖,其增殖抑制作用与诱导G2/M周期阻滞有关。     

三氧化二砷对人肝癌细胞的体外作用及其机制

目的观察三氧化二砷(As2O3)对人肝癌细胞BEL7402的体外作用及其机制.方法采用MTT法观察As2O3对BEL7402细胞的生长抑制率;流式细胞仪测定经不同浓度As2O3处理后的BEL7402细胞周期、凋亡相关蛋白bcl-2阳性细胞百分率、增殖细胞核抗原(PCNA)变化.结果As2O3可显著抑制BEL7402细胞生长,且剂量-效应关系显著(r=0.965 0,P＜0.01),半数抑制浓度(IC50)为4.93 μmol·L-1;As2O3能显著下调PCNA蛋白表达(P＜0.01),并使细胞周期阻滞在G2/M期,但对bcl-2表达无影响(P＞0.05).结论As2O3可有效抑制人肝癌BEL7402细胞生长,其机制可能与下调PCNA表达及阻滞细胞周期有关.     

槲皮素对肝肿瘤细胞生长周期的影响

目的 :研究槲皮素对肝肿瘤细胞细胞周期的影响并探讨其机制。方法 :用联合四唑盐比色法研究槲皮素对肿瘤细胞生长的抑制作用 ,流式细胞仪、电镜及免疫细胞化学等方法观察槲皮素对肝肿瘤细胞株QGY ,HepG2体外生长的影响。结果 :槲皮素对HepG2和QGY均有抑制作用 ,使 G0 /G1期细胞增加 ,G2 /M期和S期细胞减少 ,出现凋亡峰 ,电镜下可凋亡小体。 4 8,72h后对HepG2的作用更明显。免疫细胞化学显示使用槲皮素后 ,2种细胞中增殖细胞核抗原 (PCNA)的阳性表达均减弱 ,而P2 1WAF1的表达均增强 ,Bax仅在HepG2细胞中表达增强。结论 :槲皮素对 2种肝肿瘤细胞株都有一定的抑制作用 ,可能主要通过增强 2种细胞株的P2 1WAF1的表达及减弱PCNA的表达诱导G0 /G1期阻滞及细胞凋亡     

熊去氧胆酸选择性诱导人肝癌细胞株HepG2凋亡探讨

目的 探讨熊去氧胆酸（UDCA）对人肝癌细胞株HepG2、肝细胞株QSG-7701增殖、凋亡及对Survivin、Caspase-3表达的影响.方法 UDCA孵育两种细胞后,分别采用MTT法、流式细胞仪、电镜、免疫组化法等观测相关指标.结果 UDCA能抑制HepG2增殖,诱导其凋亡,并具有浓度、时间依赖性.随着Survivin表达下调,Caspase-3表达上调（r=-0.9853,P＜0.01）、细胞增殖抑制（r=0.9789,P＜0.05）、凋亡指数增加（r=-0.9632,P＜0.05）.肝细胞株QSG-7701中无Survivin表达.UDCA对肝细胞株QSG-7701增殖、凋亡无明显影响.结论 UDCA可能通过干预Survivin的表达,选择性地诱导肝癌细胞株HepG2凋亡.     

一种新的吲哚咔唑类化合物(ZWM233)的体外抗肿瘤作用及机制探讨

目的探讨ZWM233体外对多种肿瘤细胞株的增殖抑制及对K562细胞的凋亡诱导作用。方法采用MTT法检测ZWM233对K562、HL-60、A549、HeLa及HCT-116等10种肿瘤细胞株的增殖抑制作用;流式细胞仪检测对K562细胞周期的影响;AnnexinV/PI双染法考察对K562细胞的凋亡诱导作用;Western blot检测K562细胞中凋亡相关蛋白bax、bcl-2、Caspase-3、Caspase-9及PARP的变化,同时检测蛋白激酶C(PKC)各亚型、GSK-3β、ERK1/2、JNK及其磷酸化水平的变化。结果 ZWM233体外能有效抑制多种肿瘤细胞株的增殖,其中对K562细胞作用明显,IC50为2.81μmol.L-1;流式细胞仪检测K562细胞被明显阻滞在G2/M期,并诱导其凋亡;Western blot结果显示ZWM233作用K562细胞24 h后,可明显下调抗凋亡蛋白bcl-2的表达,引起Caspase-9、Caspase-3及下游底物PARP的剪切,诱导K562细胞凋亡。Western blot检测结果进一步显示药物作用24 h后PKCδ的表达有所降低,其下游分子p-GSK-3β及p-ERK的表达水平降低,而p-JNK蛋白的表达水平升高。结论ZWM233体外能有效抑制K562细胞生长,并通过激活线粒体途径诱导其凋亡,其机制可能是通过下调PKCδ,进一步抑制p-GSK-3β及p-ERK1/2的表达来发挥凋亡诱导作用。     

洛铂对肝癌细胞HepG2的放疗增敏效应

目的 探讨洛铂对肝癌细胞的放疗增敏效应.方法 用MTT法确定洛铂对肝癌细胞株HepG2半数抑制浓度(IC50),流式细胞仪检测1/4 IC50、1/8 IC50洛铂对HepG2细胞周期、凋亡的影响,蛋白免疫印迹检测凋亡相关蛋白Bcl-2、Bax、Caspase-3的表达,细胞克隆形成实验研究洛铂对HepG2的放射增敏比.结果 洛铂对肝癌细胞株HepG2细胞毒作用呈剂量依赖性,半数抑制浓度为1.85μg/ml,不同浓度洛铂组(1/4 IC50组、1/8 IC50组)均观察到HepG2细胞凋亡和G2/M期阻滞明显增加(P＜0.05);两组洛铂干预组肝癌细胞Bcl-2表达下降,Bax、Caspase-3表达水平升高;洛铂对肝癌细胞HepG2的放疗增敏比分别是1.12、1.28.结论 洛铂具有放射增敏作用;其机制可能与促进肝癌细胞凋亡以及细胞G2/M期阻滞相关.     

丙戊酸对人脑胶质母细胞瘤细胞株抑制增殖及诱导凋亡作用研究

目的研究丙戊酸(2-propylpentanoic acid,VPA)体外对人脑胶质母细胞瘤细胞株增殖抑制、诱导细胞周期阻滞及促进凋亡的作用,为临床治疗提供理论依据。方法 MTT比色法检测VPA对胶质母细胞瘤细胞株的杀伤作用;流式细胞术检测其对细胞周期及凋亡的影响作用;Western blot法检测乙酰化组蛋白H3(acetyl-Histone H3)、乙酰化组蛋白H4(acetyl-histone H4)表达量变化情况。结果 VPA对胶质瘤母细胞瘤细胞株SF295、U87具有抑制增殖作用,诱导细胞周期阻滞于G2/M期,乙酰化组蛋白H3、H4表达量呈时间依赖性增加。大剂量可以诱导出现凋亡。结论 VPA能够在体外抑制胶质瘤细胞生长,诱导细胞周期阻滞及促进细胞凋亡,其机制可能与促进组蛋白乙酰化有关。     

川楝素对人肝癌细胞株HepG2生物学行为的影响

目的 观察川楝素对人肝癌细胞株HepG2增殖和凋亡的影响,并研究其诱导凋亡的机制.方法 取人肝癌HepG2细胞株培养后,随机分为对照组(不添加任何药物)、观察组(加川楝素80 mmol/ml),培养细胞24、48、72 h后,酶标仪测定人肝癌HepG2细胞增殖抑制率;流式细胞仪检测人肝癌HepG2细胞周期和凋亡率.结果 两组对肝癌HepG2细胞增殖抑制率差异有统计学意义(x2=5.33,P＜0.05);两组S期、G0/G1期、M/G2期的细胞比率(t=6.31、6.26、6.56,均P＜0.05)、细胞凋亡率差异有统计学意义(x2=6.15,P＜0.05).结论 川楝素可明显抑制人肝癌细胞HepG2的恶性增殖,并诱导肿瘤细胞凋亡.     

无蹼壁虎抗肿瘤活性成分对HepG2细胞增殖、迁移及凋亡的影响

目的观察无蹼壁虎抗肿瘤活性成分(Gekko Swinhonisanti-neoplasm active component,GSAAC)对人肝癌HepG2细胞增殖、迁移及凋亡的影响。方法 GSAAC与体外培养的人肝癌HepG2细胞共培养,分别以MTT法和Transwell小室检测其对细胞增殖及迁移、侵袭的影响;免疫组化法检测PCNA的表达;Hochest33342荧光染色法、TUNEL法观察GSAAC对HepG2细胞的作用;流式细胞术检测细胞周期及早期凋亡率。结果 GSAAC(25～400 mg.L-1)可明显抑制HepG2细胞的增殖、迁移和侵袭能力,呈浓度依赖性;Ho-chest33342、TUNEL染色及流式细胞术结果显示,GSAAC可诱导细胞发生早期凋亡,阻滞HepG2细胞从S期进入G2期。结论 GSAAC可能通过影响细胞周期进而抑制HepG2细胞增殖和迁移并诱导细胞发生凋亡,进而实现抑制肿瘤的作用。     

古抑菌素A诱导人肝癌HepG2细胞凋亡及对脆性组氨酸三联体蛋白和凋亡相关蛋白表达的影响

目的:研究组蛋白去乙酰化转移酶抑制剂古抑菌素A(TSA)对人肝癌HepG2细胞的抑制作用以及对脆性组氨酸三联体(FHIT)蛋白和凋亡相关蛋白caspase-3、bax、bcl-2表达的影响,初步探讨其诱导凋亡的机制。方法:以不同浓度TSA(125、250、500、1000、2000nmol·L-1)处理体外培养的人肝癌HepG2细胞,孵育24、48h后采用MTT法、以吸光度值和抑制率为指标检测细胞的生长抑制情况;分别用原位末端脱氧核苷转换酶标记(TUNEL)法和免疫细胞化学法检测TSA(250、1000nmol·L-1)作用后细胞凋亡率和细胞中FHIT、caspase-3、bax、bcl-2的蛋白表达;同时设立溶剂为对照组。结果:与对照组比较,不同浓度TSA作用后吸光度值降低,抑制率升高,并呈明显的剂量依赖和时间依赖关系;TUNEL阳性细胞百分率升高(P<0.01)、细胞中FHIT、cas-pase-3、bax蛋白表达增强(P<0.05),bcl-2的变化不明显(P>0.05)。结论:TSA可能通过上调FHIT、caspase-3、bax蛋白的表达而诱导肝癌HepG2细胞凋亡。     

Anti-tumor effect of germacrone on human hepatoma cell lines through inducing G2/M cell cycle arrest and promoting apoptosis

Germacrone is one of the main bioactive components in the traditional Chinese medicine Rhizoma curcuma. In this study, the anti-proliferative effect of germacrone on the human hepatoma cell lines and the molecular mechanism underlying the cytotoxicity of germacrone were investigated. Treatment of human hepatoma cell lines HepG2 and Bel7402 with germacrone resulted in cell cycle arrest and apoptosis in a dose-dependent manner as measured by MTT assay, flow cytometric and fluorescent microscopy analysis, while much lower effect on normal human liver cell L02 was observed. Flow cytometric analysis revealed that germacrone induced G2/M arrest in the cell cycle progression that was associated with an obvious decrease in the protein expression of cyclin B1 and its activating partner CDK1 with concomitant inductions of p21. Hoechst 33258 and Annexin V/PI staining results showed that the total cell number in apoptosis associated with a dose-dependent up-regulation of Bax and down-regulation of Bcl-2/Bcl-xl was increased. In the meantime, the up-regulation of p53 and reactive oxygen species increase were observed, which suggested that germacrone might be a new potent chemopreventive drug candidate for liver cancer via regulating the expression of proteins related to G2/M cell cycle and apoptosis, and p53 and oxidative damage may play important roles in the inhibition of human hepatoma cells growth by germacrone.     

正常人肝细胞和肝癌细胞对力达霉素诱导的有丝分裂性细胞死亡的差异

[摘要]目的：探讨力达霉素（lidamycin, LDM）诱导人肝癌BEL-7402和正常人肝L-02细胞出现的有丝分裂性细胞死亡的差异。方法：采用MTT法观察LDM对BEL-7402和L-02细胞生长曲线的影响;使用Giemsa染色和流式细胞术观察有丝分裂性细胞死亡特征;用Western blot法检测蛋白表达变化。结果：LDM抑制BEL-7402和L-02细胞的生长,二者均表现出有丝分裂性细胞死亡的特征,即细胞体积增大、G2/M期阻滞、出现多核化,但BEL-7402细胞对LDM更敏感。在LDM处理的BEL-7402和L-02细胞中,与凋亡相关的Bax和Smac的蛋白表达水平没有增加,caspase-3和caspase-9未被活化,但L-02细胞的Akt通路被激活。结论：人正常L-02细胞对LDM引起的有丝分裂性细胞死亡明显低于人肝癌BEL-7402细胞,对LDM的反应敏感性存在差异的原因可能与Akt信号通路有关。     

Natural plant extract tubeimoside I promotes apoptosis-mediated cell death in cultured human hepatoma (HepG2) cells

Tubeimoside I (TBMS I), an extract from Chinese herbal medicine Bolbostemma paniculatum (MAXIM.) FRANQUET (Cucurbitaceae) has been shown as a potent anti-tumor agent for a variety of human cancers, but yet to be evaluated for hepatoma that is highly prevalent in Eastern Asian countries including China. Here, we examined in vitro the cytotoxic effects of TBMS I on human hepatoma (HepG2) and normal liver (L-02) cell lines. We also investigated TBMS I-induced molecular events related to apoptosis in HepG2 cells. The results show that TBMS I inhibited the proliferation of both HepG2 and L-02 cells in a dose- and time-dependent manner, but HepG2 cells appeared more sensitive to the agent. When exposed to TBMS I for 24, 48 and 72 h, IC?? for HepG2 cells versus L-02 cells were 15.5 vs. 23.1, 11.7 vs. 16.2, 9.2 vs. 13.1 (μM, p<0.01), respectively. TBMS I induced cell shrinkage, nuclear condensation and fragmentation, cell cycle arrest at the G2/M phase, mitochondrial membrane disruption, release of cytochrome c from the mitochondria, activation of caspase 3 and 9, and shifting Bax/Bcl-2 ratio from being anti-apoptotic to pro-apoptotic, all indicative of initiation and progression of apoptosis involving mitochondrial dysfunction. Taken together, these results indicate for the first time that TBMS I potently inhibited growth in HepG2 cells by mediating a cascade of apoptosis signaling pathways. Considering its sensitivity of HepG2 cells, preferential distribution in the liver and natural product origin, TBMS I therefore may have a great potential as a chemotherapeutic drug candidate for hepatoma.     

Cucurbitacin E inhibits the proliferation of hepatoma cells in vitro and in vivo through induction of G2/M phase arrest

Objective Cucurbitacins are the highly oxygenated tetracyclic triterpenes,which are predominantly found in the Cucurbitaceae family but are also present in several other families of the plant kingdom.A number of compounds of this group have been investigated for their cytotoxic,hepatoprotective,anti-inflammatory,cardiovascular and anti-diabetic activities.In China,the cucurbitacin preparation,which contains mostly cucurbitacin B and cucurbitacin E,has been clinically used for the treatment of the primary liver carcinoma.It has been previously reported that cucurbitacin E could produce cytotoxicity against a variety of cancer cells,and various mechanisms were implicated in its cytotoxic effect.The present study is to investigate the effect of cucurbitacin E on hepatoma cells in vitro and in vivo and to study their potential mechanisms of action.Methods The MTT assay was used to assess the viability of human HepG2 and BEL7402 hepatoma cells in vitro after treatment with different concentrations of cucurbitacin E.The cell cycle distribution was determined by flowcytometric analysis after propidium iodide(PI)staining.The cell cycle-related proteins were detected using western blotting analysis.Implanted mouse hepatoma H22 model was built to evaluate the growth inhibitory effect of cucurbitacin E in vivo in mice.Results Our studies found that cucurbitacin E(10-300 nM)produced anti-proliferative effect on human HepG2 and BEL7402 hepatoma cells in vitro without cytotoxicity.According to flowcytometric analysis,cucurbitacin E arrested the cell cycle at G2/M phase in both HepG2 and BEL7402 hepatoma cells after 24 h treatment.Cucurbitacin E induced the decrease in the level of CDK1 protein and the increase in the level of p21 protein,but had no effect on the levels of cyclin A,cyclin B1 and Cdc25C protein.In in vivo anti-tumor experiment,cucurbitacin E had significant inhibitory effects on the growth of mouse H22 hepatoma cells.Conclusions Cucurbitacin E inhibited the proliferation of hepatoma cells in vitro and in vivo,at least in part,through induction of cell cycle arrest at G2/M phase,which was mediated by concomitant upregulation of p21 and downregulation of CDK1.We consider that cucurbitacin E may be useful in the treatment of liver cancer.     

三七总皂苷对三种不同人肝癌细胞株增殖的影响

目的探讨三七总皂苷在体外对三种不同的人肝癌细胞株增殖的影响。方法体外培养人肝癌细胞株HepG2、BEL-7402、SMMC-7721和正常人肝细胞株L-02,给予不同浓度（0、10、100、200、400和800μg．mL^-1）的三七总皂苷分别培养24、48和72h后,采用MTT比色法检测细胞增殖的情况。结果不同浓度三七总皂苷处理正常肝细胞L-02相同时间或相同浓度（800μg．mL^-1）三七总皂苷处理正常肝细胞L-02不同的时间时,其对细胞增殖的抑制率均较低。而不同浓度三七总皂苷处理HepG2、BEL-7402和SMMC-7721肝癌细胞株相同时间或相同浓度（800μg．mL^-1）三七总皂苷处理不同的时间时,其细胞增殖抑制效应随作用浓度的增加或作用时间的延长而升高。结论三七总皂苷可显著抑制体外培养的三种不同人肝癌细胞株的增殖,且呈浓度与时间依赖性。     

PI3K/mTOR抑制剂BEZ235抑制HepG2细胞增殖及与阿霉素的协同效应

目的探讨PI3K/Akt和mTOR双重抑制剂BEZ235对HepG2肝癌细胞增殖和凋亡的影响,并观察BEZ235与阿霉素合用的联合作用。方法采用MTT法检测HepG2细胞增殖;流式细胞术分析细胞周期变化;AnnexinⅤ-FITC试剂盒检测细胞凋亡;免疫印迹法检测蛋白表达水平。结果BEZ235 2.5μmol.L-1～7.5μmol.L-1能够抑制HepG2细胞的增殖,且抑制作用呈时间和剂量依赖性。HepG2细胞经BEZ235处理后,细胞阻滞于G1期,cyclinD1表达水平下调,而cyclinB1的表达则不受影响。BEZ235明显增强了阿霉素对HepG2细胞的抑制作用,并促进阿霉素下调β-catenin的表达。结论 BEZ235对人肝癌细胞HepG2的生长具有显著的抑制作用;联合应用BEZ235和DOX协同抑制HepG2细胞的增殖,其机制可能与共同调节β-catenin通路相关。     

Anti-proliferative activity of fenretinide in human hepatoma cells in vitro and in vivo

N-(4-hydroxyphenyl)-retinamide (fenretinide) is a synthetic derivative of all-trans-retinoic acid and induces apoptosis in several cancer cell lines. We determined the anti-cancer activity of fenretinide using human hepatoma cell lines, Bel-7402, HepG2 and Smmc-7721. An in-vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that fenretinide exhibited growth inhibition in these cell lines, with IC50 values ranging from 13.1 to 15.5 micromol/l. In Bel-7402 cells, apoptosis with 15 micromol/l fenretinide for 0 and 48 h was 3 and 48%, respectively. In-vivo studies using the Bel-7402 xenografted athymic mouse model showed tumor inhibition rates ranging from 37.2 to 57.2%, with fenretinide administration once per 3 days at the rate of 25-100 mg/kg. Western blot analysis further showed down-regulation of procaspase-3, X-linked inhibitor of apoptosis protein and poly(ADP-ribose) polymerase cleavage in Bel-7402 cells treated with 15 mumol/l fenretinide for 48 h. Overexpression of p53 was observed in a time-dependent manner, along with a decrease in the Bcl-2/Bax ratio. Depolarized mitochondrial membranes were found in fenretinide-induced apoptotic cells, in a time-dependent manner. We conclude that fenretinide effectively inhibits the proliferation of Bel-7402, both in vitro and in vivo. Both procaspase-3 and p53-mediated apoptotic pathways are involved in its potent anti-cancer activity.