肝症口服液含药血清对转化生长因子α诱导人肝癌细胞SMMC—7721增殖和凋亡的研究

目的：观察肝症口服液含药血清对转化生长因子（TGFα）诱导人肝癌细胞增殖和凋亡的影响。方法：采用血清药理学方法,以病理鼠血清作对照,应用MTT比色法观察中药鼠血清对TGFα诱导人肝癌细胞SMMC－7721增殖的抑制作用。用流式细胞术检测中药血清对肝癌细胞凋亡和细胞周期的影响。结果：中药血清对TGFα诱导的肝部细胞SMMC－7721增殖有明显的抑制作用,抑制效应呈时间依赖性。中药血清能促进肝癌细胞凋亡,使用胞滞留于G0／1期,降低S期细胞百分比和增殖指数。结论：肝症口服液含药血清能够抑制TGFα诱导的人肝癌细胞增殖,促进其凋亡。     

腺病毒介导的人野生型p53、GM-CSF和B7-1基因转移诱导肝癌细胞的生长抑制和凋亡

目的 观察携带人野生型p53、GM－CSF和B7－1基因的重组腺病毒载体（BB－102）转染BEL－7402、HLE及HuH-7肝癌细胞后p53基因的表达,以及诱导肝癌细胞凋亡,影响肝癌细胞的增殖。方法 BB－102以MOI为50pfu/细胞感染肝癌细胞系BEL－7402（p53基因为野生型）、HLE及HuH-7(p53基因为突变型）。免疫组织化学法检测BB－102携带的p53基因的表达,TdT法原位检测肝癌细胞的凋亡。结果 BB－102携带的p53基因能在转染了BB－102的肝癌细胞中高效表达。转染BB－102后肝癌细胞生长明显受到抑制;染毒后第4－10d期间,BEL－7402、HLE及HuH-7三株肝癌细胞的平均受抑率分别为58．5％、81．5％及71．1％,其中对p53基因突变的肝癌细胞的抑制程度要大于对p53基因为野生型肝癌细胞的抑制程度。转染BB－102还能诱导肝癌细胞的凋亡。结论 BB－102通过其介导p53基因的表达抑制肝癌细胞的增殖,这为BB－102应用于肝癌的基因治疗提供实验依据。     

黄芪水提物对体外培养人肝癌细胞增殖及代谢的影响

目的研究中药黄芪(AMB)提取物对体外培养的人肝癌细胞的抑癌活性.方法AMB经粉碎、浸提、超速离心、减压浓缩、冷冻干燥得AMB提取物.人肝癌SMMC-7721细胞经AMB提取物处理不同时间后以MTT法测其对人肝癌SMMC-7721细胞线粒体代谢活性的影响,以细胞记数法观察了其对细胞增殖的影响.结果①AMB提取物明显抑制人肝癌SMMC-7721细胞的生长,降低线粒体代谢活性;②经AMB提取物处理24 h后的人肝癌细胞,即使更换为正常培养基,其线粒体代谢活性及细胞增殖与对照相比仍差异显著.结论中药AMB提取物含抑癌活性物质,能抑制体外培养的肝癌细胞增殖和降低线粒体代谢活性.     

丹参素诱导人肝癌细胞株SMMC7721凋亡的研究

丹参素是传统中药丹参的一种水溶性提取物,具有抗氧化和潜在的抗肿瘤作用。目的：探讨丹参素体外对人肝癌细胞株SMMC7721的诱导凋亡作用及其机制。方法：分别以0mg／L、10mg／L、20mg／L、30mg／L、40mg／L丹参素作用SMMC7721细胞24、48和72h后．采用MTT法检测细胞抑制率。透射电子显微镜观察细胞凋亡形态。AnnexinV-FITC／PI双染法检测不同浓度（O-40mg／L）丹参素和40mg／L丹参素作用不同时间（0-48h）对SMMC7721细胞的凋亡：RT-PCR法检测不同浓度（0-40mg／L）丹参素作用SMMC7721细胞24h后p53mRNA表达。结果：丹参素可呈时间和剂量依赖性地抑制SMMC7721细胞增殖和诱导凋亡：透射电子显微镜下可见典型的细胞凋亡特征。随着丹参素浓度的升高．D53mRNA表达亦明显上调。结论：丹参素在一定浓度范围内可呈时间和剂量依赖性地抑制SMMC7721细胞增殖并诱导细胞凋亡,其机制可能与p53表达上调有关。     

缺氧对人肝癌细胞株SMMC7721中HCCR表达的影响及其调控机制

背景：缺氧是实体瘤微环境的基本特征之一。人宫颈癌基因（HCCR）是新近发现的一种癌基因．在多种人类肿瘤中过表达。然而,尚缺乏HCCR在肿瘤缺氧环境中的表达及其调控机制的研究。目的：探讨缺氧对人肝癌细胞株SMMC7721中HCCR表达的影响及其调控机制。方法：SMMC7721细胞分别接受缺氧培养以及LY294002（P13K特异性抑制剂）和PD98059（MEK1特异性抑制剂）预处理＋缺氧培养,以蛋白质印迹法检测HCCR表达：将含HCCR启动子片段的荧光素酶报告基因质粒转染SMMC7721细胞,检测缺氧对HCCR启动子转录活性的影响。结果：缺氧环境下SMMC7721细胞中HCCR蛋白表达和转录活性均较常氧环境中升高,LY294002和PD98059可抑制缺氧环境下HCCR蛋白表达。结论：缺氧状态下人肝癌细胞株SMMC7721中HCCR蛋白表达和启动子转录活性增高。可能是肿瘤细胞在缺氧实体瘤组织中存活和快速增殖的重要机制之一。缺氧状态下HCCR蛋白表达受P13K／Akt和MAPK这两条信号通路的调节。     

皂荚提取物对人肝癌细胞相关癌基因表达的调控作用及端粒酶的影响

目的：研究皂荚提取物对人肝癌细胞的增殖、相关癌基因表达的调控作用及端粒酶的影响。方法：体外培养人肝癌细胞bel-7402，检测不同浓度皂荚提取物（0．05mg／ml、0．1mg/ml、0．2mg／m1）对人肝癌细胞bel-7402细胞增殖、细胞周期、肝癌相关基因（bax、bcl-2、p53）的表达及端粒酶活性的影响。结果：0．05mg／ml-0．2mg／ml浓度组皂荚提取液对人肝癌细胞bel-7402细胞增殖、调控癌基因与抑癌基因、促进癌细胞凋亡、抑制端粒酶活性差异均具有显著性意义（P〈0．05或P〈0．01）。结论：皂荚提取物能够抑制人肝癌细胞增殖，促进细胞凋亡。     

PGK1基因沉默对SMMC7721肝癌细胞增殖的影响

目的:观察PGK1基因沉默对SMMC7721肝癌细胞增殖的影响。方法:常规体外培养SMMC7721肝癌细胞,Lipofectamine 3000方法将sh RNA-PGK1质粒及阴性载体转染至SMMC7721细胞;荧光实时定量PCR及Western Blot检测PGK1的表达,MTT检测细胞相对存活率。结果:与正常SMMC 7721细胞相比,在PGK1沉默的肝癌细胞中,PGK1基因的表达降低,细胞的相对存活率减少。结论:PGK1基因沉默能够抑制SMMC7721肝癌细胞的增殖。     

腺病毒介导XAF1基因诱导人肝癌细胞株SMMC7721凋亡的实验研究

背景：X连锁凋亡抑制蛋白（XIAP）相关因子1（XAF1）是新近鉴定的肿瘤抑制基因,在许多人类恶性肿瘤中低表达甚至不表达。目的：研究Ad5/F35腺病毒介导XAF1基因诱导人肝癌细胞株SMMC7721凋亡的作用及其可能机制。方法：构建重组腺病毒Ad5/F35-XAF1、对照病毒Ad5/F35-Null和报告病毒Ad5/F35-增强型绿色荧光蛋白（EGFP）,分别按不同感染复数（MOI）在同一作用时间点感染人肝癌细胞株SMMC7721。以荧光显微镜和流式细胞仪检测Ad5/F35-EGFP的感染效率;分别以逆转录聚合酶链反应（RT-PCR）和蛋白质印迹法检测XAF1mRNA和蛋白表达;以甲基噻唑基四唑（MTT）法检测细胞增殖率;以Annexin V-FITC/PI双染法和原位末端标记TUNEL法检测细胞凋亡率;以蛋白质印迹法检测凋亡相关蛋白caspase-3、caspase-8和caspase-9的表达。结果：Ad5/F35-EGFP感染48h,MOI为2.0时,92%以上的SMMC7721细胞表达绿色荧光蛋白。Ad5/F35-XAF1感染48h后,SMMC7721细胞中XAF1 mRNA和蛋白表达增高,细胞增殖受到抑制,细胞凋亡剂量依赖性地增多,并伴随凋亡相关蛋白caspase-3、caspase-8和caspase-9的裂解。结论：重组腺病毒Ad5/F35-XAF1在人肝癌细胞株SMMC7721中具有很强的感染效率,可促进XAF1基因表达,且能明显抑制人肝癌细胞增殖和诱导凋亡,此作用可能与XAF1激活了内、外源性凋亡通路有关。     

鹅脱氧胆酸衍生物HS-1200对肝肿瘤细胞株凋亡及增殖的影响

目的探讨鹅脱氧胆酸衍生物HS-1200诱导肝肿瘤细胞株凋亡及抑制增殖的作用及机制。方法分别用40、60及80p-M的HS-1200作用于肝肿瘤细胞株BEL7402,于作用后12、24及36h采用MTT检测细胞活性,流式细胞术、DNA梯状条带、荧光显微镜检测细胞凋亡,Western—blot法检测bcl-2、bax、细胞色素C及caspase-3的表达。结果HS-1200可有效地抑制BEL7402生长,其作用随药物浓度提高和作用时间延长而增强,呈一定的剂量、时间依赖性;FCM结果表明,随作用浓度和作用时间延长,凋亡率显著增加,有显著性差异（P〈0．05）;Ho-echst33258染色结果显示细胞呈凋亡形态学改变,凝胶电泳显示典型的凋亡梯形条带,Westernblot结果显示为HS-1200可提升bax、细胞色素C及caspase-3的表达,降低bcl-2的蛋白表达水平。结论HS-1200对BEL7402有显著的抑制增殖及诱导凋亡的作用,其机理可能为提升bax、细胞色素C及caspase-3的表达,降低bcl-2的表达;HS-1200可能是一种有效的治疗肝癌的化疗药物。     

Bcl-2核酶对SMMC7721细胞的促凋亡机制

目的 观察Bel-2核酶对SMMC-7721细胞的作用,探讨bcl-2抑制细胞凋亡的机制。方法 经脂质体介导的方法将PMTr-neo(正向Bcl-2核酶真核表达载体)导入SMMC 7721细胞中．细胞克隆转移扩大培养后,采用TUNEL,TRAP结合ELISA流式细胞仪,免疫组化技术检测SMMC 7721／PMTr-neo细胞增殖及细胞凋亡。结果 较对照组SMMC 7721／PMTr-neo细胞bcl-2表达水平显著下降,伴有显著细胞凋亡现象及端粒酶活性下降,结论 Bcl-2核酶可促进SMMC 7721细胞发生凋亡,并降低细胞端粒酶活性,为反义技术在肝癌治疗中应用提供理论依据。     

siRNA沉默Cyclin E基因对肝癌HepG2、SMMC-7721和BEL-7402细胞增殖和侵袭能力的影响

目的:观察siRNA沉默Cyclin E基因表达对肝癌HepG2、SMMC-7721和BEL-7402细胞增殖和侵袭能力的影响.方法:构建2个靶向Cyclin E基因siRNA载体,转染人肝癌HepG2、SMMC-7721和BEL-7402细胞.RT-PCR、Western blot检测转染后HepG2、SMMC-7721和BEL-7402细胞Cyclin E基因mRNA和蛋白表达水平.CCK-8试验、软琼脂克隆形成实验检测HepG2、SMMC-7721和BEL-7402细胞增殖、克隆形成能力.流式细胞术、transwell试验分别检测HepG2、SMMC-7721和BEL-7402细胞周期和侵袭能力.结果:构建的2个Cyclin E基因siRNA载体插入序列与所设计序列均一致;转染HepG2、SMMC-7721和BEL-7402细胞后,干扰1组、干扰2组与空白对照组和阴性对照组比较,C y c l i n E m R N A和蛋白表达量均显著降低(P<0.05),细胞生长速度延缓,软琼脂细胞集落形成数、穿透细胞数均显著降低(P<0.05),S和G2/M期细胞比例减少,G0/G1期细胞比例增加.结论:沉默肝癌细胞Cyclin E表达水平,可有效抑制细胞生长、增殖和侵袭能力.     

肝癌细胞株中肿瘤特异性抗原MAGE、GAGE、BAGE基因表达的研究

目的 研究MAGE、GAGE、BAGE基因在肝癌细胞株中的表达情况,评价这些肿瘤特异性抗原作为肿瘤分子标记以及肿瘤免疫治疗特异性靶位的可能性。 方法 用RT-PCR检测国内建株的肝癌细胞株SMMC-7721、QQY-7701、BEL-7402中MAGE-1、MAGE-3、GAGE1-8、GAGE1-2和BAGE基因mRNA的表达,以GAPDH基因作为检测内对照,并与非肿瘤肝穿组织比较。 结果 肝癌细胞株SMMC-7721表达MAGE-1和BAGE基因;QQY-7701表达MAGE-3和BAGE基因;BEL-7402表达MAGE-1和GAGE1-2基因;3株肝癌细胞至少表达其中一个基因。肝硬化病人肝穿刺组织中MAGE、GAGE、BAGE基因表达均为阴性。 结论 MAGE、GAGE、B A G E肿瘤特异性抗原可以作为肝癌早期诊断的分子标记,并具有作为肝癌免疫治疗特异性靶位的潜在价值。     

三氧化二砷对肝癌细胞表达PTTG1和VEGF的影响及其意义

目的 观察三氧化二砷(As2O3)对人肝癌细胞株BEL-7402和SMMC-7721的作用及其可能机制.方法 采用四甲基偶氮唑蓝(MTT)法检测As2O3对两种细胞的生长活性;用流式细胞仪测定经不同浓度As2O3溶液处理后的两种细胞的周期变化,并用Annexin V-FITC与PI双染法检测细胞凋亡;用实时逆转录-聚合酶链反应(RT-PCR)检测As2O3对两种细胞垂体肿瘤转化基因1(PTTG1)和血管内皮生长因子(VEGF)mRNA表达的影响;用蛋白免疫印迹法(western-blotting)检测As2O3对两种细胞PTTG1和VEGF蛋白表达的影响.结果 As2O3可显著抑制BEL-7402和SMMC-7721细胞的生长,并呈量效关系(r=0.973,P<0.01;r=0.985,P<0.01),半数抑制浓度(IC50)分别为4.38 μmol/L和5.16 μmol/L.BEL-7402和SMMC-7721经As2O3处理后均发生显著凋亡(P<0.01).As2O3能显著下调两种细胞PTTG1和VEGF mRNA及蛋白的表达(P<0.01),并使细胞周期阻滞在G2/M期.结论 As2O3可有效抑制人肝癌细胞的生长增殖,其机制可能与诱导细胞凋亡、阻滞细胞周期及下调PTTG1和VEGF的表达有关.     

肝癌干细胞逃避5-氟尿嘧啶单药杀伤可能是造成化疗失败的重要原因

目的通过观察5-氟尿嘧啶(5-FU)处理人肝癌细胞系BEL-7402和SMMC-7721,分析细胞生物学特性的变化。方法采用Cell Counting Kit-8法检测5-FU作用前后肝癌细胞系BEL-7402和SMMC-7721增殖能力的变化;采用流式细胞法检测细胞周期组成变化和细胞群体中肿瘤干细胞标志物EpCAM、ABCG2和ICAM-1阳性细胞的比例变化。结果 10μg.ml-15-FU作用48h后,BEL-7402和SMMC-7721细胞增殖均明显受抑制(P<0.05);两细胞系实验组静息期(G0/G1期)细胞比例较对照组均明显升高(P<0.05);两细胞系中肿瘤干细胞标志物阳性细胞比例均明显升高(P<0.05)。结论肝癌细胞系BEL-7402及SMMC-7721中的肿瘤干细胞能够逃避一定剂量5-FU的杀伤作用。肝癌干细胞逃避5-FU单药杀伤可能是造成临床化疗失败的重要原因。     

腺病毒介导的环氧合酶-2反义RNA对肝癌细胞株生长的影响

目的探讨环氧合酶-2(COX-2)的表达与肝癌的关系,并构建表达人COX-2反义RNA的腺病毒载体,研究其对人肝癌细胞生长的抑制作用。方法采用免疫组织化学法探讨34例肝癌组织COX-2 的表达与肝癌病理特征的关系。采用基因重组法把人COX-2的cDNA片段反向克隆于穿梭质粒pHCMVSP1A,获得pAd-AShcox-2,通过脂质体与pJM17共转染293细胞,经同源重组产生编码COX-2反义RNA的重组腺病毒--Ad-AShcox-2。经聚合酶链反应法鉴定为阳性克隆者大量扩增、纯化,转染人肝癌细胞株SMMC-7402和SMMC-7721,采用免疫细胞化学、细胞集落形成率及流式细胞术检测其对肝癌细胞生长、凋亡及细胞周期分布的影响。结果34例肝癌组织中有28例COX-2高度表达,阳性率达82.4%; COX-2的表达水平与肝癌的病理分级有关,与甲胎蛋白、细胞类型、有无肝内转移无关。成功构建、扩增、纯化得到编码COX-2反义RNA的重组腺病毒Ad-AShcox-2,滴度达1.06×1012PFU/ml;Ad-AShcox- 2转染两种肝癌细胞株后,发现高度表达COX-2的SMMC-7402 COX-2表达水平明显降低,细胞凋亡率明显增加,出现G1期阻滞,与Ad-LacZ组及空白对照组比较差异有统计学意义(P<0.05);而不表达COX- 2的SMMC-7721变化不明显。细胞集落形成实验显示SMMC-7402细胞集落形成率较低(2.7%±0.94%); 而SMMC-7721     

Eukaryotic elongation factor-1α 2 knockdown inhibits hepatocarcinogenesis by suppressing PI3K/Akt/NF-κB signaling

AIM: To assess the impact of eukaryotic elongation factor 1 alpha 2(e EF1A2) on hepatocellular carcinoma(HCC) cell proliferation, apoptosis, migration and invasion, and determine the underlying mechanisms.METHODS: e EF1A2 levels were detected in 62 HCC tissue samples and paired pericarcinomatous specimens, and the human HCC cell lines SK-HEP-1, Hep G2 and BEF-7402, by real-time PCR and immunohistochemistry. Experimental groups included e EF1A2 silencing in BEL-7402 cells with lentivirus e EF1A2-sh RNA(KD group) and e EF1A2 overexpression in SK-HEP-1 cells with e EF1A2 plasmid(OE group). Non-transfected cells(control group) and lentivirusbased empty vector transfected cells(NC group) were considered control groups. Cell proliferation(MTT and colony formation assays), apoptosis(Annexin V-APC assay), cell cycle(DNA ploidy assay), and migration and invasion(Transwell assays) were assessed. Protein levels of PI3K/Akt/NF-κB signaling effectors were evaluated by Western blot.RESULTS: e EF1A2 m RNA and protein levels were significantly higher in HCC cancer tissue samples than in paired pericarcinomatous and normal specimens. SK-HEP-1 cells showed lower e EF1A2 m RNA levels; Hep G2 and BEL-7402 cells showed higher e EF1A2 m RNA levels, with BEL-7402 cells displaying the highest amount. Efficient e EF1A2 silencing resulted in reduced cell proliferation, migration and invasion, increased apoptosis, and induced cell cycle arrest. The PI3K/Akt/NF-κB signaling pathway was notably inhibited. Inversely, e EF1A2 overexpression resulted in promoted cell proliferation, migration and invasion.CONCLUSION: e EF1A2, highly expressed in HCC, is a potential oncogene. Its silencing significantly decreases HCC tumorigenesis, likely by inhibiting PI3K/Akt/NF-κB signaling.     

人肝癌细胞系Slit/Robo启动子甲基化状态及基因表达的研究

目的 研究Slit/Robo信号通路相关基因Slit1、Slit2、Slit3和Robo1、Robo3在多种人肝癌细胞系中的表达及甲基化状态,探讨与肝癌发生和发展的关系. 方法提取9种人肝细胞癌细胞株(Hep3B、HepG2、PLC/PRF/5/PRF/5、SMMC-7721、BEL-7402、MHCC97-H,MHCC97-L、LM3、LM6)及对照细胞株L02的基因组DNA和总RNA,采用半定量逆转录聚合酶链反应技术和甲基化特异性聚合酶链反应技术检测Slit1、Slit2,Slit3和Robo1,Robo3基因的基因表达水平与启动子甲基化状态.实验数据应用Paired t检验. 结果 Slit1、Slit2、Slit3基因除个别细胞株外,在不同转移潜能细胞株中均发生了DNA甲基化,同时Slit1和Slit3在mRNA水平几乎均不表达,Slit2基因表达程度在不同转移潜能的细胞株之间存在差异,随着转移潜能的增加表达大致呈下降趋势.作为Slit2受体的Robo1基因在10株肝癌细胞株中均发生甲基化修饰,但除在SMMC-7721、BEL-7402、L02不表达外,其余7种细胞株均有表达.Robo3基因相关CpG岛在9种肝癌细胞株中均未发生甲基化,同时其在mRNA水平均无表达. 结论 Slit/Robo可能在肝癌发生和发展中发挥作用.而Robo3则在肝癌中不发生表达而且其表达沉默可能不受甲基化方式调控.     

Effects of adenovirus-mediated human cyclooxygenase-2 antisense RNA on the growth of hepatocellular carcinoma

AIM: To investigate the relation between the expression of cyclooxygenase-2 (COX-2) and liver cancer, to construct the recombinant adenovirus encoding human COX-2 antisense RNA, and to explore its effects on liver cancer cell proliferation. METHODS: We studied the expression of COX-2 in 34 cases of hepatocellular carcinoma (HCC) and SMMC7402 and SMMC7721 by immunohistochemical technique. Recombinant adenovirus Ad-AShcox-2 was constructed and transfected into human HCC cell lines SMMC7402 and SMMC7721, and its effects on COX-2 expression, cell apoptosis and cell cycle were analyzed by flow cytometry. Cell proliferation was determined by colony-forming efficiency. RESULTS: We observed COX-2 expression in 82.4% of HCC and SMMC7402 cells, but no COX-2 expression in SMMC7721 cells. In addition, recombinant adenovirus encoding antisense COX-2 fragment Ad-AShcox-2 was obtained with the titer of 1.06×1012PFU/mL. Ad-AShcox-2 could reduce the expression of COX-2 and enhance the percentage of cells in G1/G0 phase in SMMC7402 cell line. The difference of apoptotic index between the Ad-AShcox-2 group and control group was statistically significant (tcontrol group=32.62 and tAd-Lacz = 10.93, P<0.001) in SMMC7402 but not in SMMC7721. Similarly, colony-forming rates of SMMC7402 and SMMC7721 cell lines, after the transfer of Ad-AShcox-2, were (2.7±0.94)% and (33.6±4.24)%, respectively. CONCLUSION: Reduction in the expression of COX-2 can inhibit COX-2 expressing HCC cells.     

Antitumor efficacy of lidamycin on hepatoma and active moiety of its molecule

AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule. METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 cells, SMMC-7721 cells and mouse hepatoma H22 cells. The in vivo therapeutic effects of lidamycin and mitomycin C were determined by transplantable hepatoma 22 (H22) in mice and human hepatoma BEL-7402 xenografts in athymic mice. RESULTS: In terms of IC50 values, the cytotoxicity of LDM was 10 000-fold more potent than that of mitomycin C (MMC) and adriamycin (ADM) in human hepatoma BEL-7402 cells and SMMC-7721 cells. LDM molecule consists of two moieties, an aproprotein (LDP) and an enediyne chromophore (LDC). In terms of IC50 values, the potency of LDC was similar to LDM. However, LDP was 105-fold less potent than LDM and LDC to hepatoma cells. For mouse hepatoma H22 cells, the IC50 value of LDM was 0.025 nmol/L. Given by single intravenous injection at doses of 0.1, 0.05 and 0.025 mg/kg, LDM markedly suppressed the growth of hepatoma 22 in mice by 84.7%, 71.6% and 61.8%, respectively. The therapeutic indexes (TI) of LDM and MMC were 15 and 2.5, respectively. By 2 iv. injections in two experiments, the growth inhibition rates by LDM at doses of 0.1, 0.05, 0.025, 0.00625 and 0.0125 mg/kg were 88.8-89.5%, 81.1-82.5%, 71.2-74.9%, 52.3-59.575%, and 33.3-48.3%, respectively. In comparison, MMC at doses of 5, 2.5, and 1.25 mg/kg inhibited tumor growth by 69.7-73.6%, 54.0-56.5%, and 31.5-52.2%, respectively. Moreover, in human hepatoma BEL-7402 xenografts, the growth inhibition rates by LDM at doses of 0.05 mg/kg ×2 and 0.025 mg/kg ×2 were 68.7% and 27.2%, respectively. However, MMC at the dose of 1.25 mg/kg ×2 showed an inhibition rate of 34.5%. The inhibition rate of tumor growth by LDM was higher than that by MMC at the tolerated dose. CONCLUSION: Both LDM and its chromophore LDC display extremely potent cytotoxicity to hepatoma cells. LDM shows a remarkable therapeutic efficacy against murine and human hepatomas in vivo.     

Effects of Pinus massoniana bark extract on cell proliferation and apoptosis of human hepatoma BEL-7402 cells

AIM:To study the effects of Pinus massoniana bark extract (PMBE) on cell proliferation and apoptosis of human hepatoma BEL-7402 cells and to elucidate its molecular mechanism. METHODS:BEL-7402 cells were incubated with various concentrations (20-200 ug/mL) of PMBE for different periods of time. After 48 h, cell proliferation was determined by 3-(4,5-dimethyl-thiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis was evaluated by morphological observation, agarose gel electrophoresis, and flow cytometry analysis. Possible molecular mechanisms were primarily explored through immunohistochemical staining. RESULTS:PMBE (20-200 ug/mL) significantly suppressed BEL-7402 cell proliferation in a time-and dose-dependent manner. After treatment of BEL-7402 cells with 160 ug/mL PMBE for 24, 48, or 72 h, a typical apoptotic "DNA ladder"was observed using agarose gel electrophoresis. Nuclear condensation and boundary aggregation or split, apoptotic bodies were seen by fluorescence and electron microscopy. Sub-G_1 curves were displayed by flow cytometry analysis. PMBE decreased the expression levels of Bcl-2 protein in a time-dependent manner after treatment of cells with 160 ug/mL PMBE. CONCLUSION:PMBE suppresses proliferation of BEL-7402 cells in a time-and dose-dependent manner and induces cell apoptosis by possibly downregulating the expression of the bcl-2 gene.