新型血管生成抑制人内皮细胞抑制素-血管内皮细胞生长抑制因子151治疗胃癌的实验研究

目的研究重组腺病毒表达的人内皮细胞抑制素-血管内皮细胞生长抑制因子151(hENDO-VEGI151)融合蛋白对胃癌的抑制作用.方法构建携带hENDO-VEGI151融合基因的重组腺病毒载体,脂质体介导法包装重组腺病毒Ad IL-3/hENDO-VEGI151.体外检测融合基因的表达及融合蛋白的生物学活性.应用鸡胚绒毛尿囊膜(CAM)模型及荷人胃癌裸鼠模型,进一步观察融合蛋白对活体血管生成的影响和融合基因治疗活体胃癌的疗效.结果用TCID50法测定携带融合基因的重组腺病毒滴度为4.2×1011TCID50/ml;用聚合酶链反应(PCR)、逆转录(RT)-PCR和免疫组织化学方法证实融合基因可被转导入SGC-7901细胞内并稳定高效地转录和表达;Western blot显示融合蛋白可被分泌到胞外发挥作用;融合蛋白可强烈抑制ECV-304细胞生长及鸡胚绒毛尿囊膜新生血管形成.Ad IL-3/hENDO-VEGI151治疗可强烈抑制裸鼠体内种植瘤生长,明显下调肿瘤微血管密度,促进胃癌细胞凋亡.结论 hENDO-VEGI151是一条新型强效的肿瘤血管生成抑制基因,其表达产物可能通过作用于肿瘤新生血管形成的不同环节强烈抑制新血管生成和肿瘤生长,值得进一步研究.     

8型腺相关病毒介导的TRAIL基因促结肠癌细胞凋亡的实验研究

目的观察8型腺相关病毒介导的TRAIL基因对结肠癌HCT116细胞凋亡的诱导作用并探讨其作用机制.方法采用三质粒磷酸钙共沉淀方法转染HEK293细胞,制备出携带TRAIL基因的8型重组腺相关病毒;重组病毒感染结肠癌细胞及正常人肝细胞,利用台盼蓝染色计数法测定细胞生长活性;光镜下观察病毒感染后细胞大体形态改变;Hoechst染色荧光显微镜下观察细胞核形态的改变;DNA凝胶电泳观察细胞凋亡的发生;蛋白印迹检测凋亡相关基因caspase-3,caspase-8蛋白表达的变化.结果携带TRAIL基因的8型重组腺相关病毒能够激活caspase通路,促进结肠癌细胞凋亡,有效抑制结肠癌细胞的生长,而对正常人肝细胞的生长没有影响.结论8型腺相关病毒介导的TRAIL基因能够抑制结肠癌细胞HCT116的体外生长,对正常细胞没有毒性.     

一氧化氮合酶反义RNA重组腺相关病毒载体体外提高PC12细胞耐缺氧的能力

目的探讨2种分别携带神经元型一氧化氮合酶（nNOS）、诱导型一氧化氮合酶（iNOS）反义RNA重组腺相关病毒载体（rAAV-AsnNOS和rAAV-AsiNOS）提高PC12细胞耐氧能力和抑制PC12细胞凋亡的作用机制。方法将PC12细胞培养基换成分别含有rAAV—AsnNOS、rAAV-Asi—NOS和rAAV-LacZ（携带β-半乳糖苷酶的结构基因重组腺相关病毒载体）的10％胎牛血清DMEM，设立对照组，测定不同rAAV转染后PCI2细胞在不同缺氧时间下细胞生长趋势和乳酸脱氢酶（LDH）活性改变，流式细胞仪（FCM）测定细胞凋亡率，FCM和半定量RT—PCR分别分析nNOS、iNOS、p38MAPK和Caspase-3阳性细胞百分比和mRNA的表达。结果一定感染复数的rAAV对PC12细胞生长趋势无明显影响；转染rAAV-AsnNOS的PC12细胞在缺氧1—6h时LDH活性、细胞凋亡率以及nNOS、p38MAPK和Caspase-3阳性细胞百分比和mRNA表达量均较对照组、rAAV-LacZ组和rAAV-AsiNOS组均降低；转染rAAV—AsiNOS的PC12细胞在缺氧6～24h时LDH活性、细胞凋亡率以及iNOS、p38MAPK和Caspase-3阳性细胞百分比和mRNA表达量也均较对照组、rAAV—LacZ组和rAAV-AsnNOS组降低。结论在体外神经细胞缺氧模型中，转染后PC12细胞能够耐受缺氧损伤；转染rAAV-AsnNOS病毒载体的PC12细胞能够在缺氧早期抑制nNOS、p38MAPK和Caspase-3的表达，转染rAAV-AsiNOS病毒载体的PC12细胞能够在缺氧晚期抑制iNOS、p38MAPK和Caspase-3的表达。     

人β干扰素基因重组腺病毒载体的构建及在骨髓间充质干细胞的表达

目的 构建人β干扰素(hIFN-β)基因重组腺病毒,观察重组腺病毒介导的hIFN-β转染大鼠骨髓间充质干细胞(MSCs)后,细胞内hIFN-β表达情况以及重组腺病毒对MSCs生长的影响.方法 利用细菌内同源重组技术快速构建Ad-hIFN-β腺病毒重组质粒,经酶切及测序鉴定正确后转染人胚肾细胞HEK293包装成为重组Ad-hIFN-β腺病毒,并进行滴度测定.转染的MSCs行逆转录-聚合酶链反应(RT-PCR)检测细胞内hIFN-β mRNA的表达;酶联免疫吸附试验(ELISA)法检测培养液上清hIFN-β的分泌情况;噻唑蓝(MTF)比色法检测细胞活力并绘制转染后MSCs生长曲线.结果 经限制性内切酶检测、基因测序及和绿色荧光观察证实成功的构建了携带hIFN-β基因的重组腺病毒,且重组腺病毒滴度高达1×109pfu/ml.Ad-hIFN-β转染MSCs后在荧光显微镜下证实有绿色荧光;RT-PCR证明转染的MSCs内有hIFN-β mRNA的表达;ELISA检测转染组1、3、5、7、10、15、20 d上清液中hIFN-β蛋白分泌量分别为192、273.436、957、605、472、279 ng/L,明显高于对照组(P<0.01);Ad-hIFN-β转染的MSCs生长曲线与正常培养MSCs差异无统计学意义(P>0.05).结论 成功构建了携带hIFN-β基因的重组腺病毒载体,重组腺病毒转染对MSCs的增殖能力无明显影响,而且Ad-hIFN-β转染大鼠MSCs能够表达并分泌hIFN-β蛋白.     

腺病毒介导反义c-myc基因抑制人肝癌细胞生长的研究

目的观察重组腺病毒介导反义c-myc基因(Ad-ASmyc)对体外培养人肝癌细胞的生长抑制作用和裸鼠体内移植肝肿瘤的治疗效果.方法Ad-ASmyc感染人肝癌细胞系后,观察细胞生长形态变化,通过细胞生长曲线、流式细胞仪分析、逆转录-聚合酶链反应(RT-PCR)、免疫印迹法(Western blot)分析Ad-ASmyc对人肝癌细胞系SMMC-7721和HCC-9204细胞生长、c-myc和bcl-2基因表达的影响;裸鼠皮下移植瘤内注射3种不同剂量Ad-ASmyc(1×109pfu-A组,1×108pfu-B组,1×107pfu-C组)抑制裸鼠肿瘤生长的差异.结果Ad-ASmyc可高效转导人肝癌细胞系SMMC-7721和HCC-9204,抑制细胞生长(抑制率分别为48.72%和56.88%),诱导肝癌细胞G1期阻滞和凋亡,c-myc、bcl-2 RNA及c-myc蛋白水平下降;瘤内注射3种不同剂量Ad-ASmyc均可明显抑制裸鼠皮下移植肿瘤生长,抑制率分别为47.1%、77.3%和82.6%(与对照组比较,P＜0.01).结论重组腺病毒介导的反义c-myc基因能够引起人肝癌细胞c-myc、bcl-2 RNA及c-myc蛋白表达下调和细胞生长抑制,瘤内注射Ad-ASmyc治疗裸鼠皮下移植肝癌有效.     

腺病毒载体介导的Polo样激酶1短发夹环RNA对胶质瘤体内外增殖的抑制作用

目的探讨重组腺病毒载体介导的Polo样激酶1（PLK1）短发夹环RNA（shRNA）对人胶质瘤细胞株U251在体内外增殖的抑制作用。方法设计并合成针对PLK1的shRNA,并克隆至真核表达载体pEGFP—H1上,再将H1启动子和shRNA亚克隆至腺病毒穿梭质粒pAdTrack上,通过在携带有pAdeasy-1质粒的BJ5183细菌内同源重组,生成针对PLK1的shRNA重组腺病毒载体pAD-H1／PLK1,经293细胞包装产生重组腺病毒AD-H1／PLK1,感染U251细胞。应用逆转录-聚合酶链反应（RT—PCR）的方法检测U251细胞PLK1mRNA表达,流式细胞仪检测细胞凋亡以及细胞G2／M期转变情况,以噻唑蓝（MTT）比色法检测各组细胞的增殖活性。同时制备裸鼠U251细胞移植瘤模型并注射重组腺病毒,观察肿瘤生长情况。结果成功构建针对PLK1基因的RNA干扰腺病毒表达载体,与AD-H1组比较AD-H1／PLK1组在转染24h和48hU251细胞PLK1mRNA表达水平分别降低50．4％（P〈0．01）和71．9％（P〈0．01）。且感染AD-H1／PLK1病毒48h后的U251细胞凋亡率从8．3％升至65．6％（P〈0．01）,而G2／M期的细胞从21．5％增至51．4％（P〈0．01）,细胞的增殖能力则下降50％（P〈0．01）。体内实验表明重组腺病毒载体介导的PLK1shRNA也明显抑制肿瘤生长（P〈0．01）。结论腺病毒介导的RNA干扰技术可有效降低PLK1在胶质瘤细胞中的表达水平,抑制肿瘤细胞在体内外的增殖活性。     

腺病毒载体介导的PML生长抑制因子用于胆囊癌基因治疗的实验研究

目的 探讨腺病毒介导的PML基因对胆囊癌细胞（GBC-SD）的生长抑制作用。方法 用原位杂交和免疫组织化学法分别检测PMI，重组腺病毒的转导效率、GBCSD中PMI，mRNA和蛋白的表达量及表达时间，MTT法检测PML基因转染后GBC-SD的生长状况，观察转染PML基因后GBC-SD的致瘤能力的变化。结果 腺病毒滴度为100MOI时被感染的胆囊癌细胞可达100％，Ad-PML感染的GBC-SD能高效表达PML-mRNA和PML蛋白，表达时间可持续2周以上，PML对GBC-SD体外生长具有明显抑制作用，Ad-PML感染的GBC-SD不能在裸鼠体内形成肿瘤。结论 腺病毒介导的PML基因能在GBC-SD细胞中稳定、高效表达，并能显著抑制GBC-SD细胞的体外生长及其在裸鼠体内的致瘤性，PML有可能用于胆囊癌的基因治疗。     

PTEN和p27Kip1共表达对前列腺癌PC-3细胞增殖和凋亡的影响

目的　通过腺病毒介导转染前列腺癌PC 3细胞 ,探讨人 10号染色体上缺失的磷酸酶和张力蛋白类似物 (PTEN)和p2 7Kip1对肿瘤细胞增殖和凋亡等方面的影响及二者的协同作用。方法　构建携带人PTEN和p2 7Kip1基因的腺病毒载体 ,体外转染PC 3细胞 ,通过RT PCR、Westernblot检测目的基因不同水平的表达。采用细胞生长试验、流式细胞仪检测PC 3转染前后细胞增殖、细胞周期和早期凋亡率的变化。结果　病毒滴度Ad PTEN为 1 8× 10 7pfu ml、Ad p2 7Kip1为 1 2× 10 9pfu ml,RT PCR检测有PTEN mRNA(46 2bp)和p2 7Kip1 mRNA (32 0bp) ,Westernblot检测有PTEN蛋白 (6 0KD)和P2 7蛋白 (2 7KD)特异表达 ,可明显抑制PC 3细胞的增殖 ,诱导细胞凋亡 ,联合基因治疗组与单基因组相比差异有显著意义。结论　成功构建携带人PTEN和p2 7Kip1的重组腺病毒载体 ,在前列腺癌细胞株PC 3得到了稳定、特异的高表达 ,联合基因疗法有望成为治疗前列腺癌的有效方法。     

一氧化氮合酶反义RNA重组腺相关病毒载体体内抑制脑缺血神经细胞凋亡的研究

目的 探讨二种分别携带神经元型一氧化氮合酶(nNOS)、诱导型一氧化氮合酶(iNOS)反义RNA重组腺相关病毒载体(rAAV-AsnNOS和rAAV-AsiNOS)在脑缺血时抑制神经细胞凋亡的作用机制.方法 运用MACO法建立脑缺血模型,闭塞1 h后分别经右侧颈内动脉缓慢注入重组病毒载体(rAAV-AsnNOS、rAAV-AsiNOS和rAAV-LacZ),继续闭塞大脑中动脉,每只转染病毒滴度为1×1010个病毒颗粒/ml,并于分别缺血早期(缺血5 h)和缺血晚期(缺血25 h)时处死模型,流式细胞术(FCM)检测硝基酪氨酸(NT)阳性细胞百分比和细胞凋亡率,逆转录反应系统(RTPCR)分析nNOS、iNOS,p38MAPK,Caspase-3 mRNA的表达.结果 在脑缺血早期,rAAV-AsnNOS组的NT阳性百分比、凋亡率以及nNOS、p38MAPK、Caspase-3 mRNA表达量较对照组、rAAV-LacZ组和rAAV-AsiNOS组的低均降低,差异有统计学意义;在脑缺血晚期,rAAV-AsiNOS组的NT阳性百分率、凋亡率以及nNOS、p38MAPK、Caspase-3 mRNA表达量较对照组、rAAV-LaeZ组和rAAV-AsiNOS组低,差异有统计学意义.结论 在体内缺血动物模型中,rAAV-AsnNOS和rAAV-AsiNOS重组病毒载体能够分别在缺血早期和晚期通过抑制NOS表达,从而抑制p38MAPK和Caspase-3基因的表达,抑制缺血后神经细胞凋亡的发生.     

Lck反义RNA重组腺病毒载体的构建及其对肾小管上皮细胞Lck表达的影响

目的:观察淋巴细胞特异性蛋白酪氨酸激酶(Lck)在肾小管上皮细胞中的表达及Lck反义RNA对其表达的影响.方法:采用RT-PCR方法从肾小管上皮细胞中获得Lck目的基因片段,将目的基因片段反向插入pDC 316质粒中,构建Lck反义RNA穿梭质粒(pDC 316-antisenseLck),经PCR、酶切及测序鉴定正确后,将此穿梭质粒与辅助质粒pBHGloxΔE1,3Cre 共转染HEK 293细胞,重组产生Lck基因反义RNA腺病毒载体(Ad-antisenseLck).用此重组腺病毒感染体外培养的肾小管上皮细胞,Western blotting方法观测此重组腺病毒载体对IL-2诱导的Lck蛋白表达的影响.结果:构建出Lck反义RNA重组腺病毒载体,此重组腺病毒载体感染培养的肾小管上皮细胞后可明显抑制IL-2诱导的Lck蛋白表达(P<0.05),抑制率可达47%.结论:成功构建出Lck反义RNA重组腺病毒载体,此载体可在肾小管上皮细胞内发挥生物学作用,显著阻抑肾小管上皮细胞的Lck蛋白表达.     

人磷酸二脂酶基因反义RNA重组腺病毒载体的构建

目的探讨人磷酸二脂酶5(PDE5)基因反义RNA重组腺病毒载体的构建方法。方法根据基因库确定具有完整PDE5A1启动子活性的cDNA基因序列,并设计反义链,两'端加内切酶修饰;通过转载体克隆方法构建转入载体(pENTR)并测序;借助Gateway腺病毒表达载体系统进行重组反应构建重组腺病毒表达载体pAd/CMV/V5/antisense PDE5A1;PacⅠ酶切后转染293A细胞系进行包装、扩增;病毒质粒酶切后电泳鉴定及PCR检测;CsCl梯度离心法纯化病毒,病毒空斑实验进行滴度测定。结果pENTR载体测序证实目的基因序列及插入方向正确;pAd/CMV/V5/antisense PDE5A1酶切后电泳鉴定,可见145bp的片段;PCR检测证明实验设计的目的反义基因成功插入腺病毒载体中;重组腺病毒滴度达108～1010/μl。结论借助Gateway腺病毒表达载体系统可成功地将人工合成的反义基因装入到腺病毒载体中;纯化病毒液量和滴度符合体内基因转染实验的要求。     

Combined antitumor effects of an adenoviral cytosine deaminase/thymidine kinase fusion gene in rat C6 glioma

OBJECTIVE: In this study, we investigated the feasibility of a double-suicide gene/prodrug therapy, involving direct introduction of the herpes simplex virus Type 1 thymidine kinase (TK) gene and the Escherichia coli cytosine deaminase (CD) gene, via a recombinant adenoviral vector, and ganciclovir (GCV) and/or 5-fluorocytosine (5-FC) treatment, in a rat C6 glioma model. METHODS: Efficient gene transfer and transduction of C6 glioma cells via a recombinant adenovirus were evaluated by infecting cells with adenovirus bearing the beta-galactosidase gene and then staining cells with X-5-bromo-4-chloro-3-indolyl-13-D-galactoside. CD/TK expression in cells infected with adenovirus bearing the CD/TK gene (ad-CD/TK) was examined by immunoblotting analysis. For in vitro cytotoxicity experiments, the cells were infected with ad-CD/TK or ad-deltaE1 (as a control). After the addition of a variety of concentrations of GCV and 5-FC, either separately or in combination, cell viability was determined by staining the cells with crystal violet solution 6 days after infection. For in vivo antitumor experiments, 1x10(5) cells were stereotactically injected into the right caudate-putamen of female Wistar rat brains. At 3 days after implantation, 1x10(8) plaque-forming units of ad-CD/TK or ad-deltaE1 (as a control) were stereotactically injected into the tumors and GCV (25 mg/kg) and 5-FC (250 mg/kg), alone or in combination, were intraperitoneally administered. Animals were then killed, and tumor volumes were measured by determining the tumor area in every fifth section, using a light microscope. RESULTS: C6 glioma cells were efficiently transduced with recombinant adenoviral vector at multiplicities of infection of 200 or more. In vitro cytotoxicity of GCV and/or 5-FC, either alone or in combination, was exclusively observed in the cells transduced with ad-CD/TK. Obvious cytotoxicity (>50% inhibition) was observed in the presence of 5-FC at concentrations greater than 30 microg/ml or GCV at concentrations greater than 0.3 microg/ml at a multiplicity of infection of 100. Additionally, cytotoxicity in the presence of both GCV and 5-FC was greater than that after single-prodrug treatments, indicating additive effects of the prodrug treatments. In in vivo experiments, the tumor volumes of the rats treated with GCV or 5-FC alone after ad-CD/TK injection (59.1+/-4.6 and 57.4+/-7.1 mm3, respectively) were significantly smaller than that of the control rats (157+/-8.9 mm3, P<0.05). Furthermore, the tumor volume of the rats treated with GCV and 5-FC in combination was 14.7+/-1.8 mm3. CONCLUSION: These results demonstrated the efficient transduction of C6 glioma cells with a recombinant adenovirus and the additive effects of CD/TK fusion gene/GCV/5-FC treatment, compared with single-gene therapy with the TK or CD gene. Therefore, our data suggest that the direct administration of a double-suicide gene/prodrug therapy has great potential in the treatment of brain tumors.     

反义AKT2 RNA逆转C6胶质瘤的细胞恶性表型

目的研究反义AKT2RNA逆转C6鼠脑胶质瘤细胞恶性表型。方法将逆转录病毒LXSN为载体的反义AKT2构建体脂质体复合物直接转染人脑胶质瘤细胞系TJ905和鼠脑胶质瘤细胞系C6,LXSN载体转染组为空载对照。随机筛选阳性克隆并应用蛋白印记和原位杂交鉴定转染。MTT法和TUNEL法评价细胞的增殖活性和凋亡,Transwell法分析侵袭能力,划痕实验研究细胞迁移能力,流式细胞法分析细胞周期,并进行GFAP的表达分析。结果转染ASAKT2cDNA后C6细胞AKT2表达显著抑制。与C6对照组和LXSN空载组比较,转染反义AKT2后C6细胞存活率均明显下降(P<0.01),凋亡指数增加(0.33vs13.67,P<0.01),侵袭能力和细胞迁移能力抑制,诱导细胞出现G0/G1细胞周期阻滞,上调GFAP的表达。结论反义AKT2RNA基因治疗通过抑制肿瘤细胞增殖、诱导凋亡、抑制肿瘤细胞侵袭与迁移并使G0/G1细胞周期阻滞逆转其恶性表型,AKT2可作为基因治疗胶质瘤的重要优选靶的。     

表达IL-24基因的溶瘤腺病毒对肝癌细胞的抑制作用

目的 研究携带IL-24基因的溶瘤腺病毒对肝癌细胞抑制生长和转移的作用.方法 构建Ad.HS4.AFP.E1A/IL-24,病毒的复制由人甲胎蛋白启动子控制,携带IL-24基因.检测病毒在不同细胞系中的选择性复制,以及对高转移潜能人肝癌细胞系MHCC97-H的生长抑制、诱导凋亡和抑制转移能力(侵袭、运动、黏附)的作用.结果 Ad.HS4.AFP.E1A/IL-24在肝癌细胞SMMC-7721、Hep3B和MHCC97-H中选择性表达,而不影响正常肝细胞L02(P＜0.05).Ad.HS4.AFP.E1A/IL-24可明显抑制MHCC97-H细胞的增殖,诱导其凋亡,并抑制其体外运动、侵袭和黏附能力(P＜0.01).RT-PCR和明胶酶谱显示其抑制肝癌作用与抑制MMP-2的表达有关.结论 携带IL-24基因的溶瘤腺病毒能够选择性抑制肝癌细胞的增殖并抑制其转移.

Abstract：

Objective To investigate the selective oncolytic role and antitumor action of a novel recombinant adenovirus containing E1A and IL-24 on hepatocellular carcinoma cell(HCC). Methods The recombinant adenovirus expressing IL-24 (Ad. HS4. AFP. E1A/IL-24) was constructed by using modified human alpha-fetoprotein (HS4-AFP) promoter to drive adenovirus E1A gene and II-24 gene.Cell Counting Kit-8 were performed to test the selective cytotoxicity of the virus in hepatocellular carcinoma cell lines SMMC-7721, Hep3B, MHCC97-H and hepatocyte cell line L02 . The mRNA and protein expression of IL-24 gene were detected by RT-PCR and western blot. Cell growth curves and Annexin V/PI assay were used to study cell proliferation and apoptosis of MHCC97-H. The anti-metastatic effects of the recombinant adenovirus were evaluated in cell adhesion, migration, and cell motion. Matrix metalloproteinase-2 (MMP-2) expression was examined by RT-PCR and zymography.Results Selective replications of Ad. HS4. AFP. E1A/IL-24 adenovirus were observed in over expression AFP cell line MHCC97-H, a highly metastatic potential HCC cell line but not in hepatocyte cell line L02. The mRNA and protein of IL-24 were also over expressed in MHCC97-H. This recombinant adenovirus also showed the significant oncolytic action on MHCC97-H but not on L02 (P＜0. 05). Besides, the recombinant adenovirus significantly inhibited MHCC97-H metastatic potential such as cell adhesion, migration and invasion as well(P＜0.01). Conclusion The selective oncolytic adenovirus expressing E1A and II-24 has a selective antitumor effect and play an inhibitory role in metastasis of HCC.     

Inhibitory effect of antisense epidermal growth factor receptor RNA on the proliferation of rat C6 glioma cells in vitro and in vivo

OBJECT: The goal of this study was to evaluate the effect of antisense epidermal growth factor receptor (EGFR) RNA on the growth of rat glioma cells in vitro and in vivo and to determine the feasibility of targeting the EGFR gene for gene therapy in gliomas. METHODS: Antisense EGFR complementary (c)DNA was transfected into C6 glioma cells by using lipofectamine. In vitro studies, Southern and Northern blot analyses, in situ hybridization, and immunohistochemical staining were designed to examine the integration and expression of antisense EGFR constructs. The 3'(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and the average number of argyrophilic nuclear organizer regions (Ag-NORs) were used to evaluate cell proliferation, whereas the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) method and microscopy were used to observe cell apoptosis. As part of the in vivo studies, parental C6 cells and C6 cells transfected with EGFR antisense cDNA were implanted stereotactically into the right caudate nucleus of Wistar rats (C6-injected animals and transfected C6-injected animals). Rats with well-established cerebral C6 glioma foci were treated intratumorally with either antisense EGFR cDNA or empty-vector DNA by using lipofectamine (treated-C6 and control treated group). The general behavior and survival of the rats, findings on magnetic resonance images of their brains, histopathological changes, proliferation activity, and apoptosis of the cerebral gliomas in each group of rats were examined. Exogenous antisense EGFR cDNA was integrated into the genome of C6 cells and expressed. In clones with a high expression of the antisense construct, there was a dramatic decrease in endogenous EGFR messenger RNA and protein levels, reduced proliferation activity, and induction of apoptosis in vitro. The mean survival time of rats injected with C6 cells was 17.3 days. The mean survival time of rats injected with C6 cells followed by treatment with empty vector in lipofectamine was 15.4 days. Survival time was significantly prolonged in 100% of the rats injected with antisense-transfected C6 cells and in two thirds of the rats injected with C6 cells followed by antisense EGFR cDNA. Magnetic resonance imaging revealed distinct cerebral tumor foci in C6-injected rats and in control rats of the treated group, but none were found in the rats injected with transfected C6 cells. Furthermore, tumor foci disappeared completely in C6-injected rats treated with antisense EGFR cDNA. The cerebral gliomas of the rats treated by injection of antisense EGFR RNA were characterized by reduced proliferation activity and the induction of apoptosis. CONCLUSIONS: The results of this study indicate that EGFR plays an important role in the genesis of malignant gliomas. It may, therefore, be an effective target of antisense gene therapy in patients with gliomas.     

Adenovirus mediated gelsolin gene therapy for orthotopic human bladder cancer in nude mice

PURPOSE: Gelsolin is an actin regulatory protein that is undetectable or reduced in human bladder tumors compared with normal epithelial cells. Whether the over expression of gelsolin could inhibit tumor growth was investigated in an orthotopic bladder cancer nude mouse model using recombinant adenovirus encoding wild-type gelsolin (Ad-GSN). MATERIALS AND METHODS: The 2 human bladder cancer cell lines KU-7 and UMUC-2 were transduced with Ad-GSN in vitro. Flow cytometric analysis was done to examine the cell cycle after transducing the adenovirus. Cell growth was compared with control groups of these cells transduced with adenovirus containing the Escherichia coli beta-galactosidase gene Ad-betagal. In vivo KU-7 cells were introduced into the bladder of nude mice (day 0), followed by 3 injections into the urethra (days 2 to 4) with Ad-GSN or Ad-betagal (1 x 10 pfu). At 8 days after initial adenovirus exposure (day 10) each bladder was sectioned and stained, and the mass of the tumor was digitally determined. RESULTS: Bladder cancer cell growth (KU-7 and UMUC-2) was inhibited after these cells were transduced with Ad-GSN in vitro. Based on flow cytometric analysis over expression of gelsolin may cause these cells to arrest or delay at the G2/M phase of the cell cycle. In the orthotopic bladder cancer model the mass of the tumor was approximately 90% less in Ad-GSN treated animals than in controls. CONCLUSIONS: Ad-GSN provides a significant tumor suppressive effect on human bladder cancer cells in this orthotopic nude mouse model. Adenovirus mediated over expression of gelsolin may be useful therapy for human bladder cancer.     

腺病毒介导反义c-myc增强骨肉瘤细胞对顺铂化疗敏感性的实验研究

目的构建表达反义cmyc的重组腺病毒,探讨重组腺病毒介导反义cmyc转染的人骨肉瘤MG63细胞对顺铂化疗敏感性的影响。方法应用基因重组技术,将约720bp的人cmyccDNA反向克隆到腺病毒载体,经重组、扩增、病毒包装后构建表达反义cmyc的重组腺病毒(AdAscmyc),并在体外转染骨肉瘤MG63细胞,采用瑞士染色、吖啶橙染色、蛋白免疫印迹(WesternBlot)、细胞体外增殖抑制试验(MTT)、流式细胞仪(FCM)等观察细胞形态、检测cmyc蛋白表达、瘤细胞体外增殖抑制、凋亡及细胞周期,分析AdAscmyc体外转染的骨肉瘤MG63细胞对顺铂化疗敏感性。结果成功构建AdAscmyc,滴度可达2×109pfu/ml,体外转染MG63细胞48h后,可降低cmyc蛋白表达,并与浓度为2.0、5.0μg/ml的顺铂作用2h后,可抑制MG63细胞的体外增殖,抑制率分为33.4%、54.2%,与对照腺病毒(AdLacZ)转染组相比差异有统计学意义(P<0.05),FCM检测证实AdAscmyc的转染可诱导骨肉瘤细胞凋亡,且顺铂治疗后凋亡比例增加,细胞周期分析显示AdAscmyc转染的骨肉瘤细胞出现G2/M期阻滞。结论腺病毒介导反义cmyc能诱导骨肉瘤MG63细胞凋亡并增加MG63细胞对顺铂化疗敏感性。     

鸟氨酸脱羧酶和S-腺苷甲硫氨酸脱羧酶双反义腺病毒对肺癌增殖和侵袭抑制作用的研究

目的探讨重组鸟氨酸脱羧酶和S-腺苷甲硫氨酸脱羧酶双反义腺病毒载体（Ad-ODC-AdoMetDCas）介导的鸟氨酸脱羧酶（ODC）和S-腺苷甲硫氨酸脱羧酶（AdoMetDC）反义RNA对肺癌细胞多胺合成、增殖和侵袭的抑制作用。方法采用活细胞计数法观察Ad-ODC-AdoMetDCas对肺癌A-549细胞生长增殖的影响,采用Western印迹法和高效液相色谱分别检测腺病毒对肺癌A-549细胞中ODC和AdoMetDC蛋白表达以及细胞内多胺含量,采用活细胞计数法和流式细胞仪分别检测腺病毒介导的鸟氨酸脱羧酶反义RNA和Ad-ODC-AdoMetDCas对A-549细胞增殖和细胞周期分布的影响,应用Matrigel侵袭实验分析腺病毒对肺癌细胞侵袭活性的改变。结果当感染效率为50时,腺病毒对A-549细胞的感染率约75％。Ad-ODC-AdoMetDCas可明显抑制A-549细胞ODC和AdoMetDC的表达。A-549细胞感染Ad-ODC-AdoMetDCas后,细胞内多胺含量明显降低。感染Ad-ODC-AdoMetDCas的A-549细胞停滞在G1期。Ad-ODC-AdoMetDCas可显著降低A-549细胞的体外侵袭能力。结论ODC和AdoMetDC双反义腺病毒能够显著抑制肺癌A-549细胞的增殖和侵袭。