血管内皮细胞生长因子反义核糖核酸对肝癌细胞生长的抑制作用

目的 探讨血管内皮细胞生长因子(VEGF)反义RNA转染人肝癌细胞后对细胞体内外生物学性状的影响。方法 将含正义、反义VEGFcDNA序列的质粒PCMV—VEGF、PCMV—FGEV及空载体质粒pcDNA3.1,在脂质体介导下导入SMMC—7721肝癌细胞,分别称为正义、反义及对照组,并通过G418筛选获得阳性克隆。细胞原位杂交和免疫组织化学方法检测转染后VEGF在肝癌细胞内的表达情况;MTT法和FCM检测转染后细胞在体外的增殖和凋亡情况;并制备裸鼠动物模型,观察转染后细胞的体内生长情况。结果 转染PCMV—FGEV后肝癌细胞内VEGF的转录及其蛋白的表达水平显著下降,但转染后体外细胞的增殖与凋亡情况均无明显变化。转染PCMV—FGEV后细胞在裸鼠体内的生长缓慢,反义组成瘤时间为(25.0±1.8)d,明显长于正义组(15.7±2.5)d和对照组(18.5±2.1)d,F=19.455,P<0.01;而平均瘤重以反义组最轻,为(0.96±0.28)g,F=21.501,P<0.01;同时反义组裸鼠肿瘤细胞发生明显的凋亡。结论 VEGF反义RNA转染人肝癌细胞可抑制肿瘤细胞VEGF的表达,在体外对细胞增殖和凋亡无影响,而体内可显著诱导细胞凋亡并抑制肿瘤生长。     

Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy

AIM To test the hypothesis to block VEGFexpression of SMMC-7721 hepatoma cells mayinhibit tumor growth using the rat hepatomamodel.METHODS Amplifiy the 200 VEGF cDNAfragment and insert it into human U6 genecassette in the reverse orientation transcribingsmall antisense RNA which could specificallyinteract with VEGF165, and VEGF121 mRNA.Construct the retroviral vector containing thisantisense VEGF U6 cassette and package thereplication-deficient recombinant retrovirus.SMMC-7721 cells were transduced with thesevirus and positive clones were selected withG418. PCR and Southern blot analysis wereperformed to determine if U6 cassette integratedinto the genomic DNA of positive clone,Transfected tumor cells were evaluated for RNAexpression by ribonuclease protection assays.The VEGF protein in the supernatant of parentaltumor cells and genetically modified tumor cellswas determined with ELISA. In vitro and in vivogrowth properties of antisense VEGF cell clonein nude mice were analyzed.RESULTS Restriction enzyme digestion andPCR sequencing verified that the antisense VEGFRNA retroviral vector was successfullyconstructed. After G418 selection, resistantSMMC-7721 cell clone was picked up, PCR andSouthern blot analysis suggested that U6cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transducedwith U6 antisense RNA cassette could express200bp small antisense VEGF RNA and secretereduced levels of VEGF in culture condition.Production of VEGF by antisense transgene-expressing cells was 65±10 ng/L per 10~6 cells,420±45 ng/L per 10~6 cells in sense group and 495±30 ng/L per 10~6 cells in the negative controlgroup, (P<0.05), The antisense-VEGF cellclone appeared phenotypically indistinguishablefrom SMMC-7721 cells and SMMC-7721 cellstransfected sense VEGF. The growth rate of theantisense-VEGF cell clone was the same as thecontrol cells. When S. C. was implanted intonude mice, growth of antisense-VEGF cell lineswas greatly inhibited compared with controlcells.CONCLUSION Expression of antisense VEGFRNA in SMMC-7721 cells could decrease thetumorigenicity, and antisense-VEGF genetherapy may be an adjuvant treatment forhepatoma.     

Inhibitory effect of antisense vascular endothelial growth factor 165 eukaryotic expression vector on proliferation of hepatocellular carcinoma cells

AIM: To construct antisense VEGF(165) eukaryotic expression vector PCDNA(3)-as-VEGF(165) and to study its expression and effect on the proliferation of hepatocarcinoma SMMC-7721 cells. METHODS: VEGF(165) cDNA was inserted into polylinker sites of eukaryotic expression vector PCDNA(3) to construct PCDNA(3)-as-VEGF(165). Then the vector was transferred into human hepatocarcinoma cell strain SMMC-7721 with cation lipofectamine 2000 mediated methods to evaluate the expression of VEGF protein and the inhibitory effect on the proliferation of hepatocarcinoma SMMC-7721 cells. RESULTS: The detection indicated the presence of VEGF cDNA in normally cultured SMMC-7721 cells by PCR. VEGF mRNA expression was notably decreased in SMMC-7721 cells by RT-PCR after PCDNA(3)-as-VEGF(165) transfection. The expression of VEGF protein was dramatically inhibited (142.01+/-7.95 vs 1 625.52+/-64.46 pg/ml(-1), P<0.01) 2 days after transfection, which correlated with the dose of PCDNA(3)-as-VEGF(165)5 gene. VEGF protein was most expressed in PCDNA(3) transferred SMMC-7721 cells but few in PCDNA(3)-as-VEGF(165) transferred cells by immunohistochemical staining. The apoptotic rate of hepatocarcinoma SMMC-7721 cells was significantly promoted (17.98+/-0.86% vs 4.86+/-0.27%, P<0.01) and the survival rate was notably decreased (80.99+/-3.20% vs 93.52+/-3.93%, P<0.05) due to antisense VEGF(165) by flow cytometry (FCM). The transfection of antisense VEGF(165) gene resulted in the inhibitory effect on the proliferation of hepatocarcinoma cells by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and the death of all hepatocarcinoma cells on day 6 after transfection. CONCLUSION: It is confirmed that antisense VEGF(165) can inhibit the expression of VEGF protein, interfere with the proliferation and induce the apoptosis of hepatocarcinoma cells in our study. Antisense VEGF(165) gene therapy may play an important role in the treatment of human hepatocarcinoma.     

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.     

Antihepatoma effect of alpha-fetoprotein antisense phosphorothioate oligodeoxyribonucleotides in vitro and in mice

AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides(S-ODNs)targeted to alpha-fetoprotein(AFP)genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immunocytochemical method or enzyme-linked immunosorbent assay.Effect of S-ODNson SMMC-7721 human hepatoma cell growth invitro was determined using microculturetetrazolium assay.In vivo antitumor activitiesof S-ODNs were monitored by measuring tumorweight differences in treated and control micebearing SMMC-7721 xenografts.Induction of cellapoptosis was evaluated by fluorescence-activated cell sorter(FACS)analysis.RESULTS Antisense S-ODN treatment led toreduced AFP gene expression.Specificantisense S-ODNs,but not control S-ODNs,inhibited the growth of heaptoma cells in vitro.In vivo,only antisense S-ODNs exhibitedobvious antitumor activities.FACS analysisrevealed that the growth inhibition by antisenseS-ODNs was associated with their cell apoptosisinduction.CONCLUSION Antisense S-ODNs targeted toAFP genes inhibit the growth of human hepatomacells and solid hepatoma,which is related totheir cell apoptosis induction.     

脂质体法转染人肿瘤坏死因子-α基因对裸鼠人肝癌移植瘤的抑制效应及其机制

背景：外源性肿瘤坏死因子（TNF）-α联合化疗药物对肿瘤的疗效较单独应用更佳,为肿瘤治疗提供了新的方向。目的：对裸鼠人肝癌移植瘤模型行脂质体介导的TNF-α基因瘤内转染,研究肝癌移植瘤的生长抑制情况及其机制。方法：经脂质体介导,以真核表达质粒pSVK3-TNF-α分别转染人肝癌细胞株SMMC-7721和裸鼠皮下SMMC-7721细胞移植瘤。测定SMMC-7721细胞的TNF-α浓度,甲基噻唑基四唑（MTT）法测定细胞杀伤率,流式细胞仪和原位末端标记（TUNEL）法检测细胞周期和凋亡情况。结果：TNF-α转基因治疗裸鼠人肝癌移植瘤结束第5d,移植瘤体积为（75.28±35.35）mm^3,显著低于对照组的（326.45±103.64）mm^3（P〈0.05）。TNF-α基因体外转染SMMC-7721细胞24、48、72h后,基因转染组每106个细胞的TNF-α表达量分别为（1680±187）pg、（1702±205）pg和（1650±164）pg,细胞杀伤率分别为（37.1±2.4）%、（79.4±4.3）%和（84.2±4.6）%。基因转染72h后,SMMC-7721细胞增殖指数为（30.5±3.2）%,显著低于对照组的（46.1±3.9）%（P〈0.05）;凋亡指数为（10.0±2.1）%,显著高于对照组的（2.7±0.4）%（P〈0.01）。结论：脂质体介导的TNF-α基因转染裸鼠人肝癌移植瘤可明显抑制肿瘤生长,其机制可能为影响肿瘤细胞生长周期以及诱导肿瘤细胞凋亡。     

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.     

生存素反义核酸诱导肝癌细胞株SMMC-7721凋亡和增加其对抗肿瘤药物敏感性的研究

背景：生存素是凋亡抑制蛋白家族的重要成员，生存素基因有可能成为肿瘤反义基因治疗的理想靶基因。目的：研究生存素反义核酸诱导肝癌细胞株SMMC-7721凋亡和增加其对常用抗肿瘤药物敏感性的作用，探讨生存素反义核酸用于肿瘤基因治疗的可能性。方法：应用基因重组技术构建pEGFP-C1-生存素反义核酸重组质粒，以脂质体转染法转染SMMC．7721细胞，用逆转录聚合酶链反应(RT-PCR)检测生存素mRNA的表达，用流式细胞仪检测细胞凋亡。将生存素反义核酸分别与7种常用抗肿瘤药物共同作用于SMMC-7721细胞，用四唑蓝(MTT)比色法测定细胞杀伤率。结果：生存素反义核酸可抑制SMMC-7721细胞中生存素mRNA的表达，从而导致细胞凋亡增加，其作用呈剂量依赖性。生存素反义核酸可增加SMMC-7721细胞对7种常用抗肿瘤药物的敏感性，明显增强药物的杀伤作用。结论：生存素反义核酸能靶向抑制野生型生存素基因的表达，提高肝癌细胞对常用抗肿瘤药物的敏感性，有可能成为肿瘤基因治疗的新方法。     

C-Met信号阻断对肝癌细胞生长和运动能力的影响

目的 用合成的c-Met反义寡核苷酸链,构建的c—Met反义质粒及U1SnRNA/核酶/反义c-Met复合体来封闭c-Met信号传导,探讨c-Met信号传导阻滞对肝癌生长和转移的影响。方法 以脂质体法将c-Met反义质粒、U 1SnRNA/核酶/反义c—Met复合体转染肝癌SF7721细胞,分别用四甲基偶氮唑蓝、生长曲线、穿膜试验观察转染前后细胞的变化。将转染前后细胞分别接种裸鼠,观察移植瘤生长及转移情况。结果c-Met反义寡核苷酸链能抑制肝癌SF7721细胞的增殖,t=3.58,P< 0.05,c-Met反义核酸质粒及U1SnRNA/核酶/反义c-Met复合体质粒转染后细胞表达受体c—Met的量均减少,且转染后细胞增殖明显减慢,为对照组的50％,F=4.87,P<0.05,侵袭运动能力减弱。初步动物实验显示转染后细胞生长较慢,潜伏期延长,35 d后反义(6.37 g)与核酶(6.14 g)实验组肿瘤生长明显低于对照组(11.01g),F=5.17,P<0.05。结论 c-Met受体基因表达在肝癌生长转移中起重要作用,阻断c-Met—SF的信号传导降低肿瘤生长甚至转移的能力。     

RNA干扰GRP78基因对肝癌细胞株SMMC-7721增殖和凋亡的影响

目的 研究shRNA干扰GRP78对肝癌细胞株SMMC-7721增殖和凋亡的影响。方法 将GRP78特异性shRNA质粒载体Pla-anti-GRP78转染SMMC-7721,采用流式细胞术(FCM)检测转染效率、分析细胞周期分布和凋亡,从蛋白和mRNA水平检测干扰GRP78效果,MTT 法检测干扰GRP78对SMMC-7721增殖的影响。结果Pla-anti-GRP78转染SMMC-7721细胞48h后,GRP78表达下降,空白对照组GRP78 mRNA的表达量为1,无关shRNA组为0.95,而Pla-anti-GRP78组为0.25(P<0.05);转染Pla-anti-GRP78的SMMC-7721细胞G2期阻滞(55.2%,P<0.05);空白对照组凋亡率为6.6%,无关shRNA组为8.1%,而Pla-anti-GRP78组高达58.2%(P<0.05)。 结论　shRNA干扰GRP78表达抑制SMMC-7721的增殖,并诱导其凋亡。     

人胰岛素样生长因子Ⅱ反义RNA对肝癌细胞恶性表型的抑制作用

研究人胰岛素样生长因子Ⅱ（ＩＧＦ－Ⅱ）反义ＲＮＡ对肝癌细胞株ＳＭＭＣ－７７２１的抑制效应。方法人ＩＧＦ－ⅡｃＤＮＡ０．１ｋｂ反向插人真核细胞表达载体ｐｃＮＡ３,获得ＩＧＦ－Ⅱ反义ＲＮＡ表达载体ｐＩＧＦ－ⅡＡＳ,将其导人人肝癌细胞株ＳＭＭＣ-７７２１,观察软琼脂培养集落形成的能力。流式细胞仪（ＦＣＭ）测定ｐＩＧＦ－ⅡＡｓ表达ＩＧＦ－Ⅱ反义ＲＮＡ对ＳＭＭＣ-７７２１细胞生长的影响。结果转导人ｐＩＧＦ－ⅡＡｓ的ＳＭＭＣ－７７２１细胞,不能在软琼脂上形成集落,ＦＣＭＭ实导人ＰＩＧＦ－ⅡＡｓ细胞Ｓ期增多,而对照组ＳＭＭＣ－７７２１细胞和带ＤＣＤＮＡ３空载体的ＳＭＭＣ－７７２１细胞则无明显变化．结论ｐＩＧＦ-ⅡＡＳ＆义ＲＮＡ体外可抑制肝癌细胞株ＳＭＭＣ－７７２１的致瘤性。     

Expression of angiostatin cDNA in human hepatocellular carcinoma cell line SMMC-7721 and its effect on implanted carcinoma in nude mice

AIM: To transfect murine angiostatin cDNA into human hepatocellular carcinoma cell line SMMC-7721 and to investigate its effects on implanted carcinoma in nude mice. METHODS: A eukaryotic expression vector of pcDNA3.1-mAST containing murine angiostatin was constructed. Then pcDNA3.1-mAST plasmid was transfected into cell line SMMC-7721 by Lipofectamine. The resistant clone was screened by G418 filtration and identified by RT-PCR and Western blotting. Nude mice were divided into three groups of 10 each. Mice in blank control group were only injected with SMMC-7721 cells. Mice in vector control group were injected with SMMC-7721 cells transfected with pcDNA3.1 (+) vector, whereas mice in angiostatin group were injected with SMMC-7721 cells transfected with pcDNA3.1-mAST plasmid. Volume, mass and microvessel density (MVD) of the tumors in different groups were measured and compared. RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). pcDNA3.1-mAST was successfully transfected into SMMC-7721 cell line and showed stable expression in this cell line. No significant difference was observed in the growth speed of SMMC-7721 cells between groups transfected with and without angiostatin cDNA. Tumor volume, mass and MVD in the angiostatin group were significantly lower than those in the blank control group and vector control group (P<0.01). The inhibitory rate of tumor reached 78.6%. Mass and MVD of the tumors only accounted for 34.6% and 48.9% respectively of those in the blank control group. CONCLUSION: Angiostatin cDNA could be stably expressed in human hepatocellular carcinoma cell line SMMC-7721 without obvious inhibitory effects on the growth of SMMC-7721 cells. When implanted into nude mice, SMMC-7721 cells transfected with angiostatin cDNA show a decreased tumorigenic capability. It suggests that angiostatin can inhibit tumor growth through its inhibition on angiogenesis in tumors.     

miR-144脂质体复合物体外抑制肝癌细胞增殖和侵袭能力及对裸鼠种植肿瘤的抑制作用初步研究*

目的 研究mi-RNA-144脂质体复合物对HepG2和SMMC-7721细胞增殖、迁移和侵袭的影响,并观察其在体内的抑瘤作用。方法 通过薄膜分散法制备DOTMA阳离子脂质体,与miR-144孵育得到miR-144脂质体复合物,通过摄取和转染实验确定DOTMP脂质体与miR-144的体积质量比;观察miR-144脂质体复合物对HepG2和SMMC-7721细胞杀伤、迁移和侵袭能力的影响。在裸鼠肝脏种植肿瘤模型,观察miR-144脂质体复合物的抑瘤作用。结果 选择DOTMP脂质体与miR-144的体积质量比为3:1,得到的miR-144脂质体复合物粒径在200 nm左右,其多分散性指数（PDI）小于0.3;DOTMP脂质体与质粒的体积/质量比（μl/μg）为3:1时,转染效率最高（P<0.05）;随着孵育时间的延长,miR-144脂质体复合物对SMMC-7721细胞和HepG2细胞的杀伤作用均增强（P<0.05）;经miR-144脂质体复合物处理过的HepG2细胞和SMMC-7721细胞迁移和侵袭距离均显著缩短（P<0.01）;与对照组比,经过miR-144脂质体复合物处理的肿瘤细胞接种肿瘤直径显著缩小（P<0.05）。结论 miR-144脂质体能够在体外和体内抑制肝癌细胞的侵袭,具有很大的应用前景。     

Downregulation of alpha-fetoprotein siRNA inhibits proliferation of SMMC-7721 cells

AIM: To study the function of α-fetoprotein (AFP) in SMMC-7721 hepatoma cells. METHODS: A hairpin siRNA expressing plasmid pSilencer3.0-H1-afp was constructed and transfected into SMMC-7721 cells with Lipofectamine 2000. The expression of AFP was monitored by real-time RT-PCR and immunoassays, its effect on SMMC-7721 cell proliferation and cell death was detected by MTT and fluorescenceactivated cell sorter (FACS). RESULTS: The AFP-siRNA expressing plasmid downregulated the expression of AFP obviously (about 34%), and inhibited SMMC-7721 cell proliferation, but did not induce apoptosis. CONCLUSION: Downregulation of AFP siRNA inhibits proliferation of SMMC-7721 cells, but cannot cause apoptosis.     

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.     

Knockdown of survivin gene expression by RNAi induces apoptosis in human hepatocellular carcinoma cell line SMMC-7721

AIM: To investigate the survivin gene expression in human hepatocellular carcinoma cell line SMMC-7721 and the effects of survivin gene RNA interference (RNAi) on cell apoptosis and biological behaviors of SMMC-7721 cells. METHODS: Eukaryotic expression vector of survivin gene RNAi and recombinant plasmid pSuppressorNeo-survivin (pSuNeo-SW), were constructed by ligating into the vector, pSupperssorNeo (pSuNeo) digested with restriction enzymes Xba I and Sail and the designed double-chain RNAi primers. A cell model of SMMC-7721 after treatment with RNAi was prepared by transfecting SMMC-7721 cells with the lipofectin transfection method. Strept-avidin-biotin-complex (SABC) immunohistochemical staining and RT-PCR were used to detect survivin gene expressions in SMMC-7721 cells. Flow cytometry was used for the cell cycle analysis. Transmission electron microscopy was performed to determine whether RNAi induced cell apoptosis, and the method of measuring the cell growth curve was utilized to study the growth of SMMC-7721 cells before and after treatment with RNAi. RESULTS: The eukaryotic expression vector of survivin gene RNAi and pSuNeo-SW, were constructed successfully. The expression level of survivin gene in SMMC-7721 cells was observed. After the treatment of RNAi, the expression of survivin gene in SMMC-7721 cells was almost absent, apoptosis index was increased by 15.6%, and the number of cells was decreased in G2/M phase and the cell growth was inhibited. CONCLUSION: RNAi can exert a knockdown of survivin gene expression in SMMC-7721 cells, and induce apoptosis and inhibit the growth of carcinoma cells.     

Growth-inhibitory effects of MOB2 on human hepatic carcinoma cell line SMMC-7721

AIM:To investigate the growth-inhibiting and apoptosis-inducing effects of the gene MOB2 on human hepatic carcinoma cell line SMMC-7721.METHODS:The full-length cDNA of the MOB2 gene was amplified from human umbilical vein endothelial cells.The correct full-length MOB2 cDNA was subcloned into the eukaryotic expression vector pEGFP-C1.After lipofection of the MOB2 gene into cancer cells,the levels of MOB2 protein in the cancer cells were detected by immunoblotting.To transfect the recombined plasmid vector pEGFP-CI-MOB2 into SMMC-7721 cells,the cells were cultured in Dulbecco's Modified Eagle'sMedium with 10% fetal calf serum and glutamine,and then mixed with liposomes,Lipofectamine 2000 and the plasmid vector pEGFP-CI-MOB2.RESULTS:We observed the growth and proliferation of SMMC-7721 cells containing pEGFP-CI-MOB2 and analyzed their apoptosis and growth cycle phases by flow cytometry.We successfully transfected the recombined plasmid vector pEGFP-CI-MOB2 into SMMC-7721 cells and screened for a single clone cell containing MOB2.After transfection,MOB2 enhanced growth suppression,induced apoptosis,increased the ratio of G0/G1,significantly inhibited the advance of cell cycle phase,and arrested cells in G0/G1 phase.CONCLUSION:MOB2 overexpression induces apoptosis and inhibits the growth of human hepatic cancer cells,which may be useful in gene therapy for hepatic carcinoma.     

塞来昔布联合 NK 细胞对裸鼠人肝癌皮下移植瘤生长的影响

目的：观察塞来昔布联合NK细胞对裸鼠人肝癌细胞SMMC-7721皮下移植瘤生长的影响,并探讨其可能的作用机制。方法选择裸鼠40只,制备人肝癌细胞SMMC-7721移植瘤模型,随机分为对照组、NK细胞组、塞来昔布组及联合干预组各10只。 NK细胞组瘤内注射NK细胞悬液0．6 mL,每7 d注射1次,共注射5次;塞来昔布组从接种后第3天起给予塞来昔布100 mg/kg灌胃,每天1次,连续35 d;联合干预组同时给予塞来昔布和NK细胞,给药剂量及途径与单用组相同;对照组灌胃和瘤内注射等量生理盐水。35 d后切取移植瘤组织计算体积,称取瘤质量,并计算抑瘤率;TUNEL法评价肿瘤细胞凋亡情况,免疫组化法检测肿瘤内VEGF、Bax、Bcl-2、caspase-3、Ki-67、NF-κB的阳性表达。结果联合干预组移植瘤体积、肿瘤质量均明显低于单用组（ P均＜0．05）,抑瘤率、凋亡指数明显高于单用组（ P均＜0．05）。联合干预组移植瘤中VEGF、Bcl-2、NF-κB、Ki-67表达明显低于单用组（ P均＜0．05）,Bax、caspase-3表达明显高于单用组（P均＜0．05）。结论塞来昔布联合NK细胞可明显抑制裸鼠人肝癌细胞SMMC-7721皮下移植瘤的生长;其作用机制可能是通过促进凋亡级联通路上Bax、caspase-3的表达,抑制VEGF、Bcl-2、NF-κB、Ki-67的表达而实现。