调控食管癌癌胚抗原基因表达对溶瘤腺病毒H101抗癌作用的影响

目的 研究调控食管癌癌胚抗原(CEA)基因表达对溶瘤腺病毒H101抗癌作用的影响,探讨影响H101敏感性的内在因素.方法 选择CEA低表达的EC9706细胞株(EC9706-SCEA)和CEA过表达的EC9706细胞株(EC9706-CEA)复苏培养,细胞生长实验检测调控EC9706细胞CEA基因表达对细胞生长的影响,通过细胞毒性实验和裸鼠体内实验检测H101对不同CEA表达水平EC9706细胞的杀伤效果.结果 细胞生长实验表明,EC9706-SCEA、EC9706-CEA和EC9706细胞群体倍增时间分别为(30.9±2.0)h、(31.1±2.5)h和(29.1±2.6)h,差异无统计学意义(P＞0.05).细胞毒性实验显示,当感染复数(MOI) ≥0.01 PFU时,H101对EC9706-SCEA细胞的抑制率明显高于EC9706、EC9706-CEA、EC9706-siCon和EC9706 -Con细胞(P＜0.05).不同时间各组裸鼠移植瘤体积测定显示,H101对治疗组裸鼠皮下移植瘤的生长均有抑制作用,但其对EC9706-SCEA治疗组移植瘤生长的抑制作用(抑瘤率为61.5％ ～ 74.5％)显著强于EC9706治疗组(抑瘤率为35.5％ ～44.8％)和EC9706-CEA治疗组(抑瘤率为32.3％～38.5％),差异有统计学意义(p＜0.05).结论 溶瘤病毒H101对EC9706-SCEA细胞的杀伤力明显增强.沉默CEA基因的表达,有望成为提高溶瘤病毒H101抗癌效果的新途径.     

TSA联合基因工程腺病毒H101治疗食管癌皮下移植瘤的研究

目的 研究曲古霉素A(TSA)对基因工程腺病毒H101杀伤食管癌EC9706细胞作用的影响,探讨HDAC抑制剂在腺病毒载体基因治疗中应用的可能性和作用机制.方法1)先成瘤后治疗组,构建裸鼠食管癌移植瘤模型,待肿瘤长至肉眼可见的肿块(约8mm ×7mm)后分组.TSA治疗组:每只每次瘤内注射1.0 μmol/L TSA;...     

重组腺病毒介导反义c-myc基因对人肝癌细胞系的治疗作用

目的：探讨重组腺病毒介导反义ｃ－ｍｙｃ基因（Ａｄ－ＡＳｍｙｃ）治疗人肝癌细胞的作用。方法：观察Ａｄ－ＡＳｍｙｃ对人肝癌细胞系的转导效率,通过细胞生长曲线、克隆形成实验、ＤＮＡ片段化分析、ＲＴ－ＰＣＲ、裸鼠皮下移植瘤治疗实验,分析Ａｄ－ＡＳｍｙｃ对人肝癌细胞系Ｂｅｌ－７４０２、ＱＳＧ－７７０１、ＳＭＭＣ－７７２１和ＨＣＣ－９２０４细胞生长和ｃ－ｍｙｃ基因表达及裸鼠肿瘤生长的抑制作用。结果：Ａｄ－ＡＳｍｙｃ可高效转导人肝癌细胞系,抑制细胞生长;转染细胞克隆形成能力降低,克隆成活率为对照组的５３．９％～６９．１％,ｃ－ｍｙｃ基因表达下降;Ａｄ－ＡＳｍｙｃ处理肝癌细胞,ＤＮＡ凝胶电泳出现明显的梯形条带,瘤内注射Ａｄ－ＡＳｍｙｃ可抑制裸鼠皮下移植瘤生长。结论：重组腺病毒介导的反义ｃ－ｍｙｃ基因转移,有可能成为肝癌基因治疗     

沉默EC9706核干细胞因子基因对裸鼠移植瘤生长的作用

观察由RNAi诱导的EC9706核干细胞因子（NS）基因沉默对裸鼠移植瘤生长的抑制作用。方法:BALB/c裸鼠15只,分为3组,siRNA干预组皮下注入pRNAT-U6.1-siNS2转染的EC9706细胞,无关siRNA对照组皮下注入pRNAT-U6.1-siC转染的EC9706细胞,空白对照组皮下注入正常EC9706细胞,接种5周分别测定各组裸鼠移植瘤体积,并应用RT-PCR技术检测裸鼠移植瘤组织中NS mRNA的表达。结果:无关siRNA对照组及空白对照组于第4天在接种部位出现肉眼可见的肿块,siRNA干预组于第6天在接种部位发现肉眼可见肿块。第5周各组裸鼠成瘤率均为100%。空白对照组、无关siRNA对照组和siRNA干预组瘤体大小分别为（1 806.40±77.75） mm3、（1 702.20±88.60） mm3和（847.00±82.25） mm3,3组相比差异有统计学意义（P<0.05）。空白对照组、无关siRNA对照组和siRNA干预组移植瘤组织中NS mRNA的表达量分别为0.681±0.033、0.685±0.034和0.497±0.056,3组相比差异有统计学意义（P<0.05）。结论:沉默EC9706细胞的NS基因可抑制裸鼠移植瘤生长,降低裸鼠体内NS mRNA的表达。沉默NS基因有可能成为治疗食管癌的新策略。      

腺病毒介导PTEN过表达抑制人脑胶质瘤U251细胞裸鼠移植瘤的生长

目的:研究含第10号染色体同源丢失性磷酸酶-张力蛋白(phosphatase and tensin homologue deleted on chromo-some 10,PTEN)基因的重组腺病毒(Ad-PTEN-GFP)对人胶质瘤U251细胞裸鼠移植瘤生长的抑制作用。方法:于裸鼠背部注射人脑胶质瘤U251细胞,建立胶质瘤裸鼠移植瘤模型。荷瘤裸鼠随机分为3组进行治疗:Ad-PTEN-GFP组,Ad-GFP组(空载体组)及PBS组(空白组),观察3组裸鼠移植瘤的生长,测量肿瘤体积,绘制肿瘤生长曲线,并观察荷瘤裸鼠的生存时间。采用TUNEL法检测移植瘤组织中细胞凋亡的情况,采用免疫组化法检测移植瘤组织中PTEN及P65蛋白的表达。结果:与Ad-GFP组相比,Ad-PTEN-GFP组移植瘤的生长受到抑制,肿瘤体积抑制率显著升高[(82.5±12.7)%vs(7.2±1.3)%,P<0.05],荷瘤裸鼠生存时间延长[(103±10)vs(58±8)d,P<0.01];TUNEL结果表明,Ad-PTEN-GFP组与Ad-GFP组相比,移植瘤细胞凋亡率明显增加[(46.4±8.3)%vs(4.6±1.0)%,P<0.01];免疫组化结果显示,Ad-PTEN-GFP组与Ad-GFP组相比,移植瘤组织中PTEN蛋白的阳性表达率增高(83.3%vs 0,P<0.01),P65蛋白阳性表达率下降(16.7%vs 66.7%,P<0.01)。结论:感染Ad-PTEN-GFP后人脑胶质瘤U251细胞裸鼠移植瘤的生长受到抑制,其机制可能与P65蛋白表达的下调有关。     

辐射诱导溶瘤腺病毒联合放疗对宫颈癌细胞HeLa S3的作用效果

目的:构建受辐射诱导的EGR-1启动子调控的携带人TRAIL基因的新型溶瘤腺病毒Ad-EGR-TRAIL,研究其联合放疗对宫颈癌细胞株HeLa S3的杀伤效果.方法:构建重组腺病毒Ad-EGR-TRAIL,用腺病毒Ad-GFP检测对HeLa S3细胞的感染效率.CCK-8法检测Ad-EGR-TRAIL组、单纯放疗组以及...     

携带p16基因重组腺病毒的构建

目的 构建携带p16基因的重组腺病毒并对目的基因的表达进行研究。方法 lipofectamine介导质粒共转染293细胞构建重组腺病毒，病毒DNA提取及电泳，免疫组化检测p16蛋白表达。结果 构建的携带目的基因的重组体腺病毒，经扩增，纯化后，病毒滴度均达到了10^10 pfu/ml 以上。用Ad-LacZ为代表进行重组体腺病毒转导效率的检测，发现当MOI为625以上的感染强度时，就可使100％的体外培养的肿瘤细胞被转导。重组体腺病毒能介导p16外源基因在脑胶质瘤细胞系TJ899和TJ905细胞中表达。结论 腺病毒载体能携带p16基因在转导细胞中表达，并有很高的转导效率。     

CIK细胞对人食管癌EC9706细胞裸鼠皮下移植瘤的抑制作用

目的 探讨细胞因子激活的杀伤细胞(cytokine-induced killer cells,CIK)对人食管癌EC9706细胞裸鼠皮下移植瘤的抑制作用.方法 体外分离健康人外周血单个核细胞,干扰素-γ、白细胞介素-2、CD3单抗诱导培养14 d,流式细胞仪测细胞表型,LDH法测定不同效靶比时CIK细胞对EC9706细胞的杀伤活性.12只BALB/c裸鼠分为两组,每组6只.每只裸鼠皮下接种1×106个EC9706细胞,治疗组裸鼠同时每只经尾静脉注入3×107个CIK细胞,每周1次,连续3周,观察两组裸鼠成瘤时间、成瘤率、肿瘤体积变化.成瘤后3周,眼眶取血,流式细胞仪检测人CIK细胞;处死裸鼠,取瘤块称重,计算抑瘤率,观察肿瘤病理特点.结果 CIK细胞中CD3+CD56+细胞占42.50%,CIK细胞表面NKG2D表达率为67.10%.效靶比10:1、20:1、30:1时CIK细胞对EC9706细胞的杀伤活性分别为(28.81±0.47)%、(37.78±0.22)%、(44.31±1.06)%,差异有统计学意义(P<0.01).对照组和CIK细胞治疗组成瘤时间分别为(9.00±1.26)d、(15.67±4.37)d,差异有统计学意义(P<0.01);瘤重分别为(3.24±0.11)g、(2.10±0.10)g,差异有统计学意义(P<0.01),CIK治疗组的抑瘤率为35.19%.HE染色显示CIK细胞治疗组有较多的淋巴细胞浸润和坏死区.结论 CIK细胞对EC9706细胞裸鼠皮下移植瘤有明显的抑制作用,可能成为治疗食管癌的免疫效应细胞.     

肿瘤细胞表面柯萨奇病毒 腺病毒受体与5型腺病毒感染效率的关系

目的〖HT5"SS〗: 探讨不同肿瘤细胞系柯萨奇病毒腺病毒受体（CAR）和整合素的表达水平与5型腺病毒感染效率的关系,为腺病毒基因治疗研究奠定基础。〖HT5W〗方法〖HT5"SS〗: 利用瞬时转染CAR的真核表达质粒提高肿瘤细胞表面CAR的表达,应用抗体封闭细胞表面的CAR和整合素后,通过流式细胞仪和荧光素酶分析法测定腺病毒Ad5CMVEGFP和Ad5CMVLuc对肿瘤细胞的感染效率和基因表达水平的变化。〖HT5W〗结果〖HT5"SS〗： 不同肿瘤细胞表面CAR和整合素的表达水平是不同的,其中SMMC7721和A549细胞CAR的表达量最高,而K562细胞CAR的表达水平最低;荧光显微镜和流式细胞仪检测Ad5CMVEGFP对肿瘤细胞的感染效率,结果显示5型腺病毒对于SMMC7721和A549细胞的感染效率最高,而对于K562细胞则很低;瞬时转染表达CAR的真核质粒可提高多种肿瘤细胞表面CAR的表达,较大幅度提高了5型腺病毒的感染效率。而抗体封闭肿瘤细胞表面的CAR或整合素后,腺病毒感染效率显著下降。〖HT5W〗结论〖HT5"SS〗:肿瘤细胞表面CAR和整合素的表达水平决定了腺病毒对肿瘤细胞的感染效率。     

Src酪氨酸激酶抑制剂dasatinib对人食管鳞癌细胞KYSE180生长及凋亡的影响

目的:探讨Src酪氨酸激酶抑制剂dasatinib对人食管鳞癌细胞生长和凋亡的影响及其相关机制.方法:采用蛋白质印迹法检测食管鳞癌细胞株KYSE180、EC109、KYSE30和人永生化食管上皮细胞株SHEE中总Src和磷酸化Src激酶的表达.用不同剂量的Src酪氨酸激酶抑制剂dasatinib作用KYSE180细胞后,分别采用MTT法、FCM法、蛋白质印迹法和裸鼠皮下移植瘤实验观察dasatinib对KYSE180细胞Src激酶的抑制作用,以及对细胞增殖、细胞周期、细胞凋亡和裸鼠皮下移植瘤的影响.结果:KYSE180、EC109和KYSE30细胞中Src激酶显著活化,而在SHEE细胞中未见活化Src激酶.Dasatinib可显著抑制KYSE180细胞增殖,阻碍细胞G1/S期转换,促进细胞凋亡,并上调caspase 3、cytochrome C和Bax等凋亡相关蛋白的表达.另外,dasatinib可显著抑制裸鼠皮下KYSE180细胞移植瘤的生长.结论:Dasatinib可通过抑制食管鳞癌细胞增殖、促进细胞凋亡以及影响细胞周期等机制,抑制食管鳞癌细胞皮下移植瘤的生长,因此其可望成为治疗食管鳞癌的一个有效药物.     

Downregulation of Waf1, C2, C3, and major histocompatibility complex class I loci within an 18-cM region of chromosome 17 in adenovirus-transformed mouse cells

In this study, the expression of the p53 tumor suppressor gene and the p53-regulated Mdm2 and Waf1 genes was evaluated in adenovirus (Ad)-transformed mouse cells. The expected levels of p53 mRNA and protein and Mdm2 mRNA were detected in all transformed cells. However, the level of Waf1 mRNA was markedly reduced in Ad12-transformed cells and in some Ad5-transformed cells. Waf1 expression was not reduced in untransformed mouse cells infected with Ad12 or Ad5. Expression of the class 1 major histocompatibility complex (MHC) locus was downregulated in 13 Ad-transformed cell lines (derived from four different strains of mice) that exhibited reduced expression of Waf1. Waf1 is located in mouse chromosome 17 proximal to the MHC class I locus. To determine whether other chromosome 17 genes were downregulated, the cells were examined for expression of other genetic loci. Of those tested, only the C2 and C3 complement loci were expressed in mouse fibroblasts. Expression of C2 (which is within the MHC) and expression of C3 (which is 15 cM distal to the MHC) were downregulated in those transformed cells in which Waf1 and MHC class I were downregulated. The Ad12- and Ad5-transformed cells that expressed low levels of Waf1, MHC class I, C2, and C3 formed tumors in syngeneic adult mice. These data suggest that the downregulation of multiple genes within the 32 Mb of mouse chromosome 17 that includes the Waf1 locus to the C3 locus occurs in Ad mouse-cell transformation and may contribute to the tumorigenicity of transformed cells. Mol. Carcinog. 18:213–220, 1997. © 1997 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Preparation and identification of monoclona antibodies against the adenovirus vector

Objective： To prepare and identity monoclonal antibodies （McAbs） against the capsid proteins of adenovirus vector. Methods： BALB/c mice were immunized with a mixture of the purified adenovirus vector （Adv） and AI（OH）3. McAbs were produced using cell fusion technique in a conventional way. The sensitivity and specificity of monoclonal antibodies was identified by indirect enzyme linked immunosorbent assay （ELISA）, immunocytochemical staining and Western blotting. Results： Six strains of hybridoma cells （A4H11, A8C7, F1H5, G1D2, G4E3 and H2G8） that can stably secrete the IgG1 McAb against Adv were obtained. After 3 months subculture and low concentration of serum adapting culture, six strains retained their stability to secrete McAb. The ascites titers were between 1：10^6 and 1：10^8. Western blot analysis demonstrated that all the McAbs reacted with one protein （about 114 kDa） which is present in wild type 3 adenovirus （wtAd3）, wild type 5 adenovirus （wtAd5）, wild type 7 adenovirus （wtAd7） and adenovirus vector. Conclusion： Successfully prepared six strains of hybridoma cell secreted monoclonal antibodies against the hexon proteins of adenovirus vector, and provided the substantial foundation of preclinical research of adenovirus vectors.     

抗腺病毒载体单克隆抗体的制备及其初步鉴定

Objective:To prepare and identify monoclonal antibodies(McAbs)against the capsid proteins of adenovirus vector.Methods:BALB/c mice were immunized with a mixture of the purified adenovirus vector(Adv)and Al(OH)3.McAbs were produced using cell fusion technique in a conventional way.The sensitivity and specificity of monoclonal antibodies was identified by indirect enzyme linked immunosorbent assay(ELISA),immunocytochemical staining and Western blotting. Results:Six strains of hybridoma cells(A4H11,A8C7,F1H5,G1D2,G4E3 and H2G8)that can stably secrete the IgG1 McAb against Adv were obtained.After 3 months subculture and low concentration of serum adapting culture,six strains retained their stability to secrete McAb.The ascites titers were between 1:106 and 1:108.Western blot analysis demonstrated that all the McAbs reacted with one protein(about 114 kDa)which is present in wild type 3 adenovirus(wtAd3),wild type 5 adenovirus (wtAd5),wild type 7 adenovirus(wtAd7)and adenovirus vector.Conclusion:Successfully prepared six strains of hybridoma cell secreted monoclonal antibodies against the hexon proteins of adenovirus vector,and provided the substantial foundation of preclinical research of adenovirus vectors.     

Expression of coxsackie and adenovirus receptor reduces the lung metastatic potential of murine tumor cells

The coxsackie and adenovirus receptor (CAR) is involved in the epithelial cell tight junction, the downregulated expression of which is observed in different cancer types. In the present study, we examined CAR's role in tumor metastasis using a B16 melanoma and CT26 colon adenocarcinoma model of experimental metastasis. In lung metastasis, the colony number of B16 cells stably expressing CAR (B16CAR) was significantly lower than that of the control CAR-negative B16 cells. B16 and CT26 cells transiently expressing CAR, which were transduced with adenovirus (Ad) vector expressing CAR, also reduced lung metastasis, suggesting that CAR plays a role in the early stage of metastasis. CAR expression significantly decreased the accumulation of B16 cells in the lung after i.v. injection and the migration in vitro. CAR expression reduced expression of alpha(v), alpha(4), beta(3) and beta(1) integrin, which play important roles in attachment to cells or basement membrane. Thus, CAR expression likely acts as a metastatic suppressor.     

腺病毒提高腺相关病毒在耐药与非耐药肿瘤细胞中的基因表达及其机制

目的:研究利用低剂量腺病毒提高重组腺相关病毒2型(recombined adeno-associated virus,rAAV2)在耐药与非耐药肿瘤细胞中基因表达水平的新方法,并初步探讨其可能的作用机制。方法:rAAV2-GFP单独或联合复制缺陷型腺病毒(Ad5-RFP)或条件复制型腺病毒(Ad5-TERT-RFP)感染人非小细胞肺癌细胞系(NCI-H446)、人肺腺癌细胞系(A549)、人胃癌细胞系(SGC7901)、人口腔黏膜上皮癌细胞系(KB)和人口腔黏膜上皮癌耐长春新碱细胞系(KB/VCR)。荧光显微镜观察和流式细胞仪分析肿瘤细胞感染后GFP的表达;Western blotting检测感染后肿瘤细胞GFP蛋白表达及ERK和AKT磷酸化水平;Real-time PCR检测肿瘤细胞内GFP的mRNA表达量、DNA拷贝数,以及细胞表面受体HSPG、α_v integrin和FGFR-1的mRNA表达。结果:流式细胞结果显示,rAAV2-GFP联合Ad5-RFP或Ad-TERT-RFP感染肿瘤细胞24h后,GFP阳性细胞率和GFP平均荧光亮度分别提高了约0.3～3倍和4～8倍。Western blotting证实联合应用Ad5-RFP感染肿瘤细胞后24h,GFP蛋白表达增加约4～6倍,肿瘤细胞内ERK和AKT磷酸化水平升高。联合感染后细胞内GFP的mRNA表达量提高了3.83～7.33倍,DNA拷贝数未见明显改变,HSPG、α_v integrin和FGFR-1的mRNA表达轻微提高。结论:低剂量腺病毒显著提高rAAV2在耐药与非耐药肿瘤细胞中的基因表达水平,可能与激活信号传导通路、增加细胞内转录有关。     

腹腔内注射IL-2重组腺病毒、IL-3重组腺病毒增强化疗药物抗白血病作用的研究

对实验性白血病小鼠模型大剂量化疗后,直接腹腔注射IL-2重组腺病毒(Ad-IL-2)和/或IL-3重组腺病毒(Ad-IL-3),发现腹腔注射对照腺病毒载体小鼠虽经大剂量化疗,仍有大量白血病细胞浸润至骨髓、血管、肝脏及脾脏。而腹腔注射Ad-IL-2或Ad-IL-3组小鼠肿瘤生长缓慢,注射Ad-IL-2组小鼠脾NK、CTL活性显著提高,注射Ad-IL-3组小鼠腹腔巨噬细胞数量及杀伤活性明显提高,联合应用Ad-IL-2,Ad-IL-3组小鼠抗白血病作用最为明显,骨髓中虽然仍见白血病细胞,但可见较多正常造血细胞,且肝、脾中未见白血病细胞浸润。表明腹腔内注射Ad-IL-2和Ad-IL-3可显著增强大剂量化疗对白血病的治疗效果。     

Induction of G1 arrest and apoptosis in androgen-dependent human prostate cancer by Kuguacin J, a triterpenoid from Momordica charantia leaf

Glucocorticoid-induced tumor necrosis factor receptor and its ligand (GITRL) are critically involved in the regulation of immune response. In this study, we aimed to generate bone marrow-derived dendritic cells (BMDCs) transfected with recombinant adenovirus expressing GITRL (pAd-GITRL-BMDCs) and explore their therapeutic efficacy in murine Lewis lung carcinoma. In vitro, pAd-GITRL-BMDCs greatly enhanced effector T cells proliferation but markedly abrogate the suppression of Treg cells. Moreover, vaccination with pAd-GITRL-BMDCs significantly retarded tumor growth, which was accompanied with increased IFN-γ-producing CD8+ T cells and markedly decreased Treg cells in vivo. These findings suggest GITRL could enhance the immune stimulation of DC and might facilitate the potential development of DCs-based anti-tumor therapies.     

腺病毒载体的优化研究现状

本文简要综述腺病毒载体的研究现状，包括各型载体的构成、优势与缺陷，及其相应的优化策略，并指出在我国人群中腺病毒载体作为疫苗和基因治疗的工具所应采取的优化措施。     

Efficient induction of T-cell responses to carcinoembryonic antigen by a heterologous prime-boost regimen using DNA and adenovirus vectors carrying a codon usage optimized cDNA

The immunogenic properties of plasmid DNA and recombinant adenovirus (Ad) encoding the carcinoembryonic antigen (CEA) were examined in mice by measuring both the amplitude and type of immune response, and the immunogenicity of codon usage optimized cDNA encoding CEA (CEAopt) was assessed both in C57Bl/6 and CEA transgenic mice. Vectors were injected into quadriceps muscle either alone or in combination, and plasmid DNA was electroporated to enhance gene expression efficiency and immunogenicity. Injection of plasmid pVIJ/CEA followed by Ad-CEA boost elicited the highest amplitude of both CD4+ and CD8+ T-cell response to the target antigen, measured by both IFNgamma-ELIspot assay and intracellular staining. Vectors carrying cDNA of CEAopt expressed a greater amount of the CEA protein than their wild-type counterparts, and this enhanced expression was associated with greater immunogenicity. Both CD4+ and CD8+ T-cell epitopes were mapped in the C-terminal portion of the protein. In CEA transgenic mice, only immunization based on repeated injections of pVIJ/CEAopt followed by Ad-CEAopt was able to elicit a CEA-specific CD8+ T-cell response, whereas the wild-type vectors did not break tolerance to this target antigen. MC38-CEA tumor cells injected s.c. in CEA transgenic mice vaccinated with CEAopt vectors exhibited delayed growth kinetics. These studies demonstrate that this type of genetic vaccine is highly immunogenic and can break tolerance to CEA tumor antigen in CEA transgenic mice.