Agkihpin对人肝癌SMMC-7721细胞COX-2、MRP1和E-CD表达的影响

目的探讨蛇毒精氨酸酯酶(Agkihpin)影响人肝癌SMMC-7721细胞活力、增殖和迁移的机制,为肝癌的治疗提供新的思路。方法取对数生长期SMMC-7721细胞随机分为8组,分别用质量浓度为0.207～4.130 g/mL的Agkihpin处理72 h,应用免疫细胞化学、Western blotting、RT-PCR法检测环氧合酶-2(COX-2)、表皮钙黏素(E-CD)和多药耐药相关蛋白1(MRP1)蛋白表达和基因转录水平,分析三指标之间的关系。结果与未行Agkihpin处理者比较,Agkihpin处理的SMMC-7721细胞COX-2基因转录、蛋白表达均降低(P<0.01),并呈一定的浓度依赖效应;COX-2与E-CD的表达和转录均呈负相关,MRP1与E-CD的表达和转录均呈负相关,COX-2与MRP1的表达和转录均呈正相关。结论 Agkihpin可通过下调MRP、COX-2表达及上调E-CD表达抑制人肝癌SMMC-7721细胞的活力、增殖和迁移,有望用于提高肝癌细胞对化疗药物的敏感性、逆转肝癌耐药细胞的多药耐药表型、提高肝癌患者术后生存率、抑制肝癌细胞的浸润和转移。     

酪丝缬肽对人肝癌细胞SMMC-7721血管生成相关基因表达谱的影响

目的:观察小分子三肽化合物酪丝缬hk(tyroscryatide,YSV)对人肝癌细胞系SMMC-7721的抑制作用,并分析YSV对肿瘤细胞血管生成相关基因表达的影响.方法:建立人肝癌细胞SMMC-7721的体外培养体系,采用四甲基偶氮唑蓝(MTT)比色法检测YSV对体外培养的SMMC-7721的增殖抑制作用,应用功能分类基因芯片分析人肝癌细胞SMMC-7721经药物作用后血管生成相关基因表达的差异变化,同时应用RT-PCR方法验证相关基因的表达.结果:YSV能显著抑制人肝癌SMMC-7721的生长,10mg/L YSV作用72h对SMMC-7721的增殖抑制率为42.34%,与对照组比较有统计学意义(P＜0.05).在113个血管生成相关基因中,YSV组相比对照组,基因下调0.667倍以上的有7个.RT-PCR在基因水平上证实YSV能显著抑制血管内皮生长因子(VEGF)和白介素8(IL-8)的表达.结论:YSV在体外能够显著抑制人肝癌细胞SMMC-7721的生长,并能在基因水平上下调肿瘤细胞血管生成相关因子的表达.     

复方苦参注射液对肝癌细胞增殖及自噬的影响

目的研究复方苦参注射液抑制人肝癌细胞SMMC-7721增殖及诱导其自噬的作用,为复方苦参注射液用于肝癌治疗提供依据。方法复方苦参注射液(终浓度为0、0.5、1、2、4 mg/m L)处理人肝癌细胞SMMC-7721 48 h,采用MTT法检测细胞增殖抑制率;用RT-PCR及Western-blot方法检测LC3及SQSTM1的转录水平和蛋白表达水平。结果复方苦参注射液可显著抑制人肝癌细胞SMMC-7721的增殖,作用呈浓度依赖性;RT-PCR方法检测到LC3及SQSTM1的转录水平均上调;Western-blot法检测到LC3蛋白表达上调,SQSTM1蛋白表达下降。结论复方苦参注射液可显著抑制人肝癌细胞SMMC-7721并诱导细胞发生自噬现象。     

XPD对SMMC-7721肝癌细胞中DNp73和GADD45β的调控及意义

目的:观察人剪切修复基因人类着色性干皮病D组基因(xeroderma pigmentosum group D,XPD)转染至人肝癌细胞株SMMC-7721细胞后XPD、DNp73和GADD45β基因的表达变化以及对肝癌细胞生长的影响.方法:实验分4组:重组质粒SMMC-7721-pEGFP-N2-XPD(XPD组)、空载质粒SMMC-7721-pEGFP-N2组(N2组),脂质体组和SMMC-7721细胞空白对照组.应用Lipofectamine2000脂质体瞬时转染,逆转录聚合酶链反应(RT-PCR)和蛋白印迹(Western blot)法检测转XPD基因后,人肝癌细胞株SMMC-7721细胞中DNp73以及GADD45β的mRNA和蛋白质的表达量变化,并用四甲基偶氮唑盐(MTT)法检测细胞增殖的活力,流式细胞仪检测细胞凋亡的变化.结果:荧光显微镜下,XPD组和N2组细胞中观察到绿色荧光蛋白表达,说明转染成功;RT-PCR检测显示:XPD组中DNp73 mRNA相对表达量较其他3组显著下调,XPD和GADD45βmRNA相对表达量较其他3组明显上调(均P<0.01);Western blot检测显示:XPD、DNp73以及GADD45β蛋白相对表达量在各组间的差异与其mRNA各组间差异一致;MTT检测示:SMMC-7721细胞空白对照组、脂质体组、N2组、XPD组的吸光度(A)值分别为0.633±0.012,0.623±0.009,0.628±0.016,0.384±0.011,XPD组低于其他3组,差异均有统计学意义(均P<0.01),表明转染XPD后SMMC-7721细胞的增殖能力减弱.流式细胞仪检测SMMC-7721肝癌细胞凋亡:转染XPD的SMMC-7721细胞凋亡显著,凋亡率达56.53%,而其他3组均未见明显凋亡.结论:XPD基因在肝癌的发生发展中起抑制作用,癌基因DNp73的表达随XPD表达增加而降低,抑癌基因GADD45β则随XPD表达增加而增加,提示两者可能在XPD抑制肝癌细胞的生长机制中起重要作用.     

苦参素注射液联合顺铂对人肝癌SMMC-7721细胞凋亡相关基因c-myc、bcl-2和bax表达的影响

目的探讨苦参素注射液(MI)联合顺铂(DDP)对人肝癌SMMC-7721细胞凋亡相关基因c-myc、bcl-2和bax表达的影响。方法分别采用MI、顺铂及MI联合顺铂干预SMMC-7721细胞。TUNEL法检测细胞凋亡率,半定量RT-PCR法检测c-myc、bcl-2和bax mRNA表达,二步法免疫组化检测c-myc、bcl-2和bax蛋白表达。结果苦参素组、顺铂组和联合用药组细胞凋亡率显著上升,与对照组(不干预)比较差异有统计学意义(P<0.05或P<0.01),联合用药具有单纯相加或协同作用;联合用药组的细胞凋亡率显著增加,bax mRNA和蛋白表达显著升高,c-myc、bcl-2 mRNA和蛋白表达显著减少,与DDP单药组比较差异有统计学意义(P<0.05或P<0.01)。结论苦参素注射液联合顺铂具有单纯相加或协同诱导肝癌SMMC-7721细胞凋亡作用,其机制可能与bax基因表达上调和c-myc、bcl-2基因表达下调有关。     

端粒酶逆转录酶小干扰RNA对肝癌细胞的体外抑制作用

目的 研究靶向人端粒酶逆转录酶(hTERT)的小干扰RNA(siRNA)在肝癌细胞SMMC-7721中抗肿瘤作用。方法 针对hTERT基因编码区及非编码区，采用T7转录系统在体外合成了2条siRNA，转染SMMC-7721细胞。以四甲基偶氮唑盐试验、逆转录聚合酶链反应及western blot观察其对SMMC-7721细胞增殖、hTERT mRNA及蛋白表达的影响。结果 2条siRNA以剂量依赖性方式抑制了SMMC-772l细胞增殖，当给药浓度为100nmol／L时，对hTERT mRNA及蛋白表达有明显的抑制作用。结论 靶向hTERT的siRNA对hTERT基因表达有抑制效果，有可能发展为一种新的抗肿瘤药物。     

黄芩苷对肝癌细胞SMMC-7721 JAK-STAT信号通路STAT3的影响

目的:探讨黄芩苷对肝癌细胞SMMC-7721JAK-STAT信号通路STAT3的影响.方法:将肝癌细胞SMMC-7721分为4组:对照组、黄芩苷组、AG490组、黄芩苷+AG490组.应用RT-PCR法检测各组肝癌细胞SMMC-7721中STAT3mRNA表达,Westernblot法检测肝癌细胞SMMC-7721中STAT3、P-STAT3蛋白表达.结果:黄芩苷可以下调肝癌细胞SMMC-7721STAT3mRNA表达,与对照组比较明显下降(0.505±0.111vs0.697±0.145,P<0.05);并可以降低STAT3蛋白的表达量(0.879±0.012vs1.087±0.015,P<0.05);还可以抑制STAT3向活化形式P-STAT3转化,与对照组比较P-STAT3表达明显下降(0.983±0.085vs1.103±0.074,P<0.05),而与AG490联合应用后P-STAT3蛋白表达量较单用黄芩苷下降明显(0.756±0.103vs0.983±0.085,P<0.05).结论:黄芩苷能下调STAT3mRNA表达水平,降低STAT3蛋白表达,还可以抑制STAT3向活化形式P-STAT3转化,...     

沉默MCM7基因后肝癌SMMC-7721细胞差异表达基因的筛选

目的:探究微小染色体维持蛋白7(minichromosome maintenance protein 7,MCM7)基因在调节肝癌细胞生长的相关机制.方法:通过s i R N A干扰技术沉默人肝癌SMMC-7721细胞中的MCM7基因表达,采用人全基因组表达谱芯片,筛查MCM7沉默后差异表达基因,进行生物信息学分析,并对部分差异表达基因进行蛋白免疫印迹法(Western blot)验证.结果:芯片筛选出在人肝癌SMMC-7721细胞中沉默MCM7基因后差异表达基因1010个,其中上调基因391个,下调基因619个.这些基因主要涉及生物大分子代谢、细胞周期调控、细胞增殖、细胞凋亡等方面,参与胞吞、肿瘤相关通路、P53信号通路、mTOR信号通路等通路的改变.Western blot对部分差异基因表达验证的结果显示CCND1、SKP2和JUP蛋白表达均下调,与芯片检测结果一致.结论:应用人基因表达谱芯片,成功筛选出沉默MCM7基因后人肝癌细胞SMMC-7721差异表达基因,为探究MCM7基因影响肝癌细胞生长提供了有效线索.     

survivin反义寡核苷酸对SMMC-7721细胞增殖和凋亡的影响

目的 观察survivin反义寡核苷酸(ASODN)对人肝癌细胞株SMMC-7721增殖和凋亡的影响.方法 人工合成survivin基因ASODN和正义ODN(SODN),并行硫代磷酸化修饰,通过脂质体途径转染SMMC-7721;分别用RT-PCR和Western blot检测survivin mRNA和蛋白表达;用MTT法检测ASODN对SMMC-7721增殖的影响;流式细胞仪检测细胞周期变化及细胞凋亡率;倒置显微镜观察细胞形态变化.结果 SMMC-7721可强表达survivin mRNA和蛋白;ASODN呈浓度依赖性抑制survivin mRNA和蛋白表达及SMMC-7721增殖,诱导细胞凋亡,使细胞阻滞于G2/M期.SODN对survivin mRNA和蛋白及SMMC-7721的增殖、细胞周期无明显抑制作用.结论 脂质体介导转染survivin ASODN可抑制细胞增殖、使细胞阻滞于G2/M期,从而促进细胞凋亡.     

肝癌细胞放射敏感性与survivin蛋白表达的关系

目的 探讨肝癌细胞放射敏感性与survivin表达的关系.方法 肝癌细胞HepG2和SMMC-7721在接受不同剂量γ射线照射后,分别采用克隆形成法、免疫细胞化学法、流式细胞术、比色法等检测细胞存活率、survivin蛋白表达、细胞周期变化和Caspase-3活性.结果 在2Gy照射下HepG2和SMMC-7721细胞的存活分数分别为0.43±0.01与0.70±0.02,SMMC-7721较HepG2放射抗拒.γ射线对SMMC-7721细胞的G2/M期阻滞时间较HepG2细胞长(48 h对24 h),在阻滞峰各剂量点SMMC-7721细胞的G2/M期比例也更高.γ射线可上调两株肝癌细胞survivin蛋白的表达,照射后48～72 h,SMMC-7721细胞的survivin蛋白表达水平显著高于HepG2细胞(t值为2.81～5.20,P值均＜0.05).而Caspase-3的活化水平在放射敏感的HepG2细胞中更高(t值为6.05～6.72,P值均＜0.01).结论 射线诱导的survivin表达上调及survivin对Caspase-3的负调控可能是SMMC-7721细胞较HepG2细胞放射抗拒的原因之一.     

Signal transduction of gap junctional genes,connexin32, connexin43 in human hepatocarcinogenesis

AIM: To investigate gap junctional intercellular communication (GJIC) in hepatocellular carcinoma cell lines, and signal transduction mechanism of gap junction genes connexin32(cx32),connexin43(cx43) in human hepatocarcinogenesis. METHODS: Scarped loading and dye transfer (SLDT) was employed with Lucifer Yellow (LY) to detect GJIC function in hepatocellular carcinoma cell lines HHCC, SMMC-7721 and normal control liver cell line QZG. After Fluo-3AM loading, laser scanning confocal microscope (LSCM) was used to measure concentrations of intracellular calcium (Ca(2+))i in the cells. The phosphorylation on tyrosine of connexin proteins was examined by immunoblot. RESULTS: SLDT showed that ability of GJIC function was higher in QZG cell than that in HHCC and SMMC-7721 cell lines. By laser scanning confocal microscopy, concentrations of intracellular free calcium (Ca(2+))i was much higher in QZG cell line (108.37 nmol/L) than those in HHCC (35.13 nmol/L) and SMMC-7721 (47.08 nmol/L) cells. Western blot suggested that only QZG cells had unphosphorylated tyrosine in Cx32 protein of 32 ku and Cx43 protein of 43 ku; SMMC-7721 cells showed phosphorylated tyrosine Cx43 protein. CONCLUSION: The results indicated that carcinogenesis and development of human hepatocellular carcinoma related with the abnormal expression of cx genes and disorder of its signal transduction pathway, such as decrease of (Ca(2+))i, post-translation phosphorylation on tyrosine of Cx proteins which led to a dramatic disruption of GJIC.     

Inhibitory effect of IGF- II antisense RNA on malignant phenotype of hepatocellular carcinoma

INTRODUCTION According to the therapeutic effect and strategy of antisense RNA for hepatocellular carcinoma (HCC), we have specifically synthesized partial cDNA of human insulin-like growth factor Ⅱ (IGFⅡ ) and constructed IGF-Ⅱ cDNA antisense eukaryotic expression vector. The constructed vector was introduced into hepatoma cell line SMMC-7721 to block the intrinsic IGF- Ⅱexpression. The biological behavior changes of hepatoma cells were observed. All these would provide scientific basis for IGF- Ⅱ antisense RNA in the treatment of HCC.     

Down-modulation of heat shock protein 70 and up-modulation of Caspase-3 during schisandrin B-induced apoptosis in human hepatoma SMMC-7721 cells

AIM: To investigate the effect of schisandrin B (Sch B) on proliferation and apoptosis of human hepatoma SMMC-7721 cells in vitro and regulation of Hsp70 and Caspases-3, 7, 9 expression by Sch B. METHODS: Human hepatoma cell line SMMC-7721 was cultured and treated with Sch B at various concentrations. Growth suppression was detected with MTT colorimetric assay. Cell apoptosis was confirmed by DNA ladder detection and flow cytometric analysis. The expression of Hsp70, Caspases-3, 7, 9 were analyzed by Western blot analysis. RESULTS: Sch B inhibited the growth of hepatoma SMMC-7721 cells in a dose-dependent manner, leading to a 50% decrease in cell number (LC50) value of 23.50 mg/L. Treatment with Sch B resulted in degradation of chromosomal DNA into small internucleosomal fragments, evidenced by the formation of a 180-200 bp DNA ladder on agarose gels. FCM analysis showed the peak areas of subdiploid at the increased concentration of Sch B. The results of Western bolt analysis showed that Hsp70 was down-regulated and Caspase-3 was up-regulated, while the activity of Caspases-7, -9 had no significant change. CONCLUSION: Sch B is able to inhibit the proliferation of human hepatoma SMMC-7721 cells and induce apoptosis, which goes through Caspase-3-dependent and Caspase-9-independent pathway accompanied with the down-regulation of Hsp70 protein expression at an early event.     

血清和糖皮质激素诱导的蛋白激酶2在肝细胞癌中过表达并介导肝癌细胞中糖原合成酶激酶-3β/β-连环蛋白信号传导

目的探讨血清和糖皮质激素诱导的蛋白激酶(SGK2)在肝癌组织与正常肝脏组织中的表达差异以及介导肝细胞癌(HCC)细胞中糖原合成酶激酶-3β(GSK-3β)/β-连环蛋白(β-catenin)信号传导的相关机制。方法收集配对的HCC及正常组织20对,采用实时荧光定量PCR技术检测SGK2 mRNA表达情况。应用蛋白质印迹法检测人肝癌细胞系Huh-7、SMMC-7721以及正常人肝细胞系L02中SGK2蛋白水平。应用SGK2 siRNA转染人肝癌细胞系SMMC-7721、Huh-7,然后使用蛋白质印迹方法检测上述转染成功细胞系中GSK-3β、β-catenin的蛋白质表达水平。计量资料以均值±标准差(±s)表示,统计学方法采用Student t检验。结果与配对正常肝组织中的表达水平相比,所有20个HCC样品中SGK2 mRNA表达上调。在两种人肝癌细胞系(Huh-7和SMMC-7721)中SGK2蛋白水平显著高于正常人肝细胞系(P<0.01)。在人HCC细胞系SMMC-7721和Huh-7中,SGK2表达下调抑制了未磷酸化GSK-3β表达。另外,在HCC细胞系中SGK2表达下调通过阻止β-catenin蛋白酶体降解来降低β-catenin的去磷酸化。结论SGK2在HCC中过表达并介导HCC细胞中GSK-3β/β-catenin信号传导。     

Effects of insulin-like growth factors-IR and -IIR antisense gene transfection on the biological behaviors of SMMC-7721 human hepatoma cells

BACKGROUND AND AIMS: Insulin-like growth factors (IGFs) are closely related to hepatocellular carcinoma growth. The study aim was to investigate the effects of IGF-IR and IGF-IIR antisense gene transfection on the biological behaviors of SMMC-7721 human hepatoma cells. METHODS: 7721-IGF-IR-AS cells (human hepatoma SMMC-7721 cells transfected with IGF-IR antisense gene in our previous study) were transfected with a plasmid vector expressing IGF-IIR cDNA in the antisense orientation by DOTAP liposome.7721-IGF-R-AS cells were obtained by selection with G418 and hygromycin. Morphological changes of the cells were observed with optic and electron microscopes. In vitro growth of the 7721-IGF-R-AS cells was observed with a soft agar test, MTT test and with naked mice inoculation test in vivo. RESULTS: The following changes were found in the SMMC-7721 cells after being transfected with the IGF-IR and IGF-IIR antisense genes: (i) the degree of malignancy of the tumor cells as revealed by cell morphology was ameliorated; (ii) the growth capability of the tumor cells in soft agar and their tumorigenicity in naked mice were significantly depressed. However, in the control groups, the SMMC-7721 cells transfected both with IGF-IR and IGF-IIR sense cDNA and SMMC-7721 cells transfected without any external genes, had no such changes. However, the cell growth curves had no significant differences among these three groups. CONCLUSION: IGF-IR and IGF-IIR antisense genes could significantly restrain the malignant behavior of human hepatoma cells and might be useful in investigating a potential route for hepatocellular carcinoma gene therapy.     

Subcellular daunorubicin distribution and its relation to multidrug resistance phenotype in drug—resistant cell line SMMC—7721／R

AIM：To investigate the correlation between subcellular daunorubicin distribution and the multidrug resistance phenotype in drug-resistant cell line SMMC-7721/R.METHODS:The multidrug resistant cell line SMMC-7721/R,a human hepatocellular carcinoma cell line,was established.Antisenes oligonucleotides(AS-ODN)were used to obtain different multidrug resistance phenotypes by inhibiting the expression of mdr1 gene and/or multidrug resistance-related protein gene(mrp)using Lipofectamine as delivery agent.Expression of mdr1 and mrp genes was evaluated by RT-PCRand Western blotting.Intracellular daunorubicn(DNR)concentration was measured by flow cytometry.Subcellular DNR distribution was analyzed by confocal laser scanning microscopy.Adriamycin(ADM)and DNR sensitivity was examined by MTTmethod.RESULTS:Low level expression of mdr1 and mrpmRNAs and no expression of P-Glycoprotein(P-gp)and multidrug resistance-related protein(P190)were detected in parental sensitive cells SMMC-7721/S,but over-expression of these two genes was observed in drug-resistant cell SMMC-7721/R,The expression of mdr1 and mrp genes in SMMC-7721/Rcells was down-regulated to the level in the SMMC-7721/Scells by AS-ODN.Intracellular DNAconcentration in SMMC-7721/Scells was 10times higher than that in SMMC-7721/Rcells.In SMMC7721/Scells intracellular DNA distributed evenly in the nucleus and cytoplasm.while in SMMC-7721/Rcells DNR distributed in a punctate pattern in the cytoplasm and was reduced in the nucleus.DNR concentration in SMMC-7721/Rcells co-transfected with AS-ODNs targeting to mdr1and rpmRNAs recovered to 25percent of that in SMMC7721/Scells.Intracellular DNA distribution pattern in drug-resistant cells treated by AS-ODN was similar to drug-sensitive cell.and the cells resistance index(RI)to DNA and AMD decreased at most from 88.0and 116.0to4.0and 2.3,repectively.Co-Transfection of two AS-ODNs showed a stronger synergistic effect than separate transfection.CONCLUSIONS:P-gp and P190are two members mediatingMDR in cellline SMMC7721/R,Intracellular drug concentration increase and subcellular distribution change are two important factos in multidrug resistance(MDR)formation.The second facto,drugs transport by P-gp andP190from cell nucleus to organell in cytoplasm,may play a more important role.     

Growth arrest and apoptosis of human hepatocellular carcinoma cells induced by hexamethylene bisacetamide

AIM: To investigate the cellular effects of hybrid polar compound hexamethylene bisacetamide (HMBA) on the growth and apoptosis of human hepatocellular carcinoma cells and to provide the molecular mechanism for potential application of HMBA in the treatment of liver cancer. METHODS: Effects of HMBA on the growth of human hepatocellular carcinoma SMMC-7721 cells were assayed by MTT chronometry. Apoptosis induced by HMBA was detected by phase-contrast microscopy, flow cytometry, propidium iodide staining and immunocytochemical analysis. RESULTS: The growth of SMMC-7721 cells was significantly inhibited by HMBA, and the growth inhibitory rate was 51.1%, 62.6%, 68.7% and 73.9% respectively after treatment with 5.0, 7.5, 10.0 and 12.5 mmol/L of HMBA. In the cells treated with 10 mmol/L of HMBA for 72 h, the population of cells at sub-G(1) phase significantly increased, and the apoptotic bodies and condensed nuclei were detected. Moreover, treatment of SMMC-7721 cells with 10 mmol/L of HMBA down-regulated the expression of Bcl-2 anti-apoptotic protein, while slightly up-regulated the level of pro-apoptotic protein Bax. CONCLUSION: Treatment with 10.0 mmol/L of HMBA can significantly inhibit the growth and induce apoptosis of human hepatocellular carcinoma SMMC-7721 cells by decreasing the ratio of Bcl-2 to Bax.     

Serum deprivation enhances DNA synthesis of human hepatoma SMMC7721 cells

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Growth-inhibiting effects of taxol on human liver cancer in vitro and in nude mice

AIM To investigate the effects of taxol on SMMC-7721 human hepatoma and its mechanisms. MLETHODS In vitro cell growth was assessed by trypan blue exclusion method. Experimental hepatoma model was established by seeding SMMC-7721 cells subcutaneously into Balb/c (nu/nu) nude mice. In vivo tumor growth was determined by measurement of tumor diameter with Vernier calipers. The syntheses of DNA,RNA and protein were analyzed by incorporation of 3H-thymidine, 3H-uridine and 3H-leucine respectively. Using light and electron microscopes to observe the morphological changes of cells including mitosis and apoptosis. RESULTS Taxol was effective against SMMC 7721 human hepetoma cell growth in the ranges of 2.5 nmol/L - 10 nmol/L with mitotic arrest and apoptosis in vitro. DNA, RNA and protein syntheses in cells were also obviously suppressed by in vitro treatment of taxol for 72 h. Taxol at 2.5 nmol/L reduced 3H-thymidine uptake to about 34% of the control value (P＜0.05). Increasing the dose of taxol to 20 nmol/L resulted in a greater decrease in 3Hthymidine incorporation to 60% of the control value (P＜0.01). At a concentration of 20 nmol/L, the 3H-uridine and 3H-leucine uptakes were reduced to 52% (P＜0.05) and 63%(P＜0.01), respectively. In vivo, taxol significantly inhibited SMMC-7721 tumor growth at 10 mg/kg, i.p., once daily for 10 d. A more than 90% decrease in tumor volume was observed by day 11 (P＜0.01) similarly with mitotic arrest and cell apoptosis. CONCLUSION Taxol has a marked anticancer activity in SMMC-7721 human hepatoma both in vitro and in nude mice. Its mechanisms might be associated with mitotic arrest, subsequently,apoptosis of the hepatoma cells. No obvious toxicity was observed with in vivo administration of taxol.     

谷氨酰胺对人肝癌细胞系SMMC-7721 增殖影响的体外研究

背景谷氨酰胺与肿瘤的发生密切相关,但其促体外培养肿瘤细胞增殖的机制目前尚不明确。目的探讨谷氨酰胺在体外影响人肝癌细胞系SMMC鄄7721增殖的可能机制。方法人肝癌细胞系SMMC鄄7721与不同浓度(0、0.5、1.0、2.0、4.0、8.0、16.0mmol/L)的谷氨酰胺共培养24h。四甲基偶氮唑蓝(MTT)比色法检测细胞增殖情况,流式细胞仪检测细胞周期变化,逆转录聚合酶链反应(RT鄄PCR)检测热休克蛋白(HSP)70的表达。结果谷氨酰胺能显著促进人肝癌细胞系SMMC鄄7721的增殖,谷氨酰胺浓度为2.0mmol/L时其促肿瘤生长的作用最强,而后又逐步下降。添加谷氨酰胺的肿瘤细胞,S期细胞比(SPF)和细胞增殖指数(PI)以及HSP70的表达较无谷氨酰胺者显著增加,且其作用随谷氨酰胺浓度的增加而增强,至浓度为2.0mmol/L时其作用最强,而后逐渐下降。结论谷氨酰胺可诱导体外培养的人肝癌细胞系SMMC鄄7721HSP70表达增高,可能是其促肿瘤生长的作用机制之一。