2-甲氧雌二醇对人肺癌细胞的放射增敏作用

目的：探讨2-甲氧雌二醇(2-ME)对肺癌细胞A549和GLC-82的放射增敏作用及其对细胞周期的影响,并从分子角度初步探讨2-ME可能的增敏机制。方法：将体外培养的人肺癌细胞A549和GLC-82分为实验组和对照组,其中实验组加入不同浓度的2-ME,对照组不含2-ME。通过MTT法定量检测2-ME对2株细胞增殖的抑制作用,集落形成实验测定2-ME对这2株细胞的放射增敏作用,流式细胞术检测细胞周期分布的变化,通过免疫沉淀法检测细胞周期素依赖性蛋白激酶2(CDK2)活性的改变。结果：分别以2-ME对人肺癌细胞GLC-82和A549的最小有效浓度(0.15625×10-6mol/L和1.25×10-6mol/L)作为放射增敏浓度,均可增加细胞对X线的敏感性,2株细胞存活曲线均见2-ME增敏组比单纯照射组整体下移,D0、Dq值均降低,增敏比：GLC-82细胞为1.98;A549细胞为2.06。细胞周期的检测表明2-ME使细胞周期阻滞于G2/M期,并呈剂量依赖性。2-ME作用后2株细胞CDK2活性均无明显改变。结论：2-ME可通过对细胞周期的调节增加非小细胞肺癌(NSCLC)细胞GLC-82和A549对射线的敏感性。     

SPD-TRAIL基因修饰间充质干细胞及其杀伤肺腺癌细胞的研究

目的 通过基因工程手段构建了可高表达十二聚体TRAIL的间充质干细胞(MSC),以期为临床应用以MSC为载体的肿瘤靶向治疗提供新的实验方法.方法 通过基因工程手段改造TRAIL基因序列,在其N-末端增加肺表面活性蛋白-D(SPD)结构域,使其形成稳定构象的十二聚体TRAIL蛋白,采用慢病毒载体基因转染间充质干细胞,得到...     

辐射敏感性启动子调控CD基因表达联合125I照射对膀肤癌EJ细胞的杀伤作用

以脂质体介导的辐射敏感性基因联合胞嘧啶脱氨酶(cytosine deantinase,CD)基因转染膀胱癌EJ细胞,研究放射性核素125 I照射后5-氟胞嘧啶(5-fluorocytosine,5-FC)对转染膀胧癌EJ细胞的杀伤作用.人工合成辐射敏感性启动子E8,将启动子克隆至质粒pCD2的CD基因上游,构建以E8为...     

辐射敏感性启动子调控CD基因表达联合125I照射对膀肤癌EJ细胞的杀伤作用

以脂质体介导的辐射敏感性基因联合胞嘧啶脱氨酶(cytosine deantinase,CD)基因转染膀胱癌EJ细胞,研究放射性核素125 I照射后5-氟胞嘧啶(5-fluorocytosine,5-FC)对转染膀胧癌EJ细胞的杀伤作用.人工合成辐射敏感性启动子E8,将启动子克隆至质粒pCD2的CD基因上游,构建以E8为启动子、CD基因为目的基因的新质粒,并采用DNA测序法测定E8和CD基因的序列;脂质体Lipofectamine2000介导pE8-CD转染膀胧癌EJ细胞,用[3]I照射(吸收剂量为2舜)后,蛋白质免疫印迹分析(Western blot)测定CD蛋白表达;在转染EJ细胞中分别加人不同剂量125 I勺和5-FC,四哇盐比色法(MTT法)测定各组细胞存活率,并以未经125 I勺照射组、未加5-FC组和5-氟尿啼吮(5-FU)组(阳性对照组)进行对照.DNA测序显示构建的pE8-CD质粒含E8启动子及CD基因序列;Westem blot可检测到CD基因表达;125 I加5-FC组细胞存活率明显低于未经125 I照射组及未加5-FC组,与5-FU组相近.这表明放射性核素与基因治疗联合对肿瘤细胞具有协同杀伤作用.     

低氧射线双调控的TK表达载体的构建及其对人乳腺癌细胞系的放射增敏作用

目的 利用AdEasy系统构建低氧射线双调控的TK表达载体- 腺病毒Ad.HRE.CArG.HSV-TK,并观察其对人乳腺癌细胞系Bcap37和MDA-MB-435的放射增敏作用。方法 用分子克隆技术构建插入HRE.CArG.HSV-TK片段的Ad.HRE.CArG.HSV-TK。CsCl梯度离心法纯化病毒,用AdEasy系统GFP标签测定病毒功能滴度。Ad.HRE.CArG.HSV-TK体外转导细胞48h,流式细胞仪测GFP阳性率,Real-time RT-PCR和Western blot检测TK mRNA和蛋白表达。MTT法检测腺病毒（Ad）转导联合放射（RT）对细胞的生长抑制作用和放射增敏比（SER）。结果 Ad.HRE.CArG.HSV-TK 滴度为2.1×109TU/mL。50 MOI病毒转导Bcap37和MDA-MB-435细胞48h,GFP阳性率分别为92％和93％,TK基因表达明显增加（P<0.05）。Ad与RT联用组（Ad＋RT）组细胞生长抑制率明显高于Ad组和相应同等剂量RT组（P<0.05）,SER为1.55。结论 应用AdEasy系统可制备同时表达GFP和TK的重组腺病毒。腺病毒对乳腺癌细胞具放射增敏作用,为进一步开展乳腺癌的基因放射治疗奠定基础。     

CXCR4 启动子的条件复制型腺病毒对肺癌细胞的靶向杀伤作用

目的:构建CXCR4启动子的条件复制型腺病毒载体CRAd-CXCR4-GFP,探究CRAd-CXCR4-GFP对肺癌细胞的靶向杀伤效应。方法:PCR法扩增人CXCR4-E1A基因并克隆至穿梭质粒pDC316-GFP,将骨架质粒pBHG-lox-E1,3Cre和重组质粒pDC316-CXCR4-GFP共转染293细胞,产生重组腺病毒CRAd-CXCR4-GFP并扩增,扩增后进行PCR鉴定和腺病毒滴度测定;real-timePCR检测5种肺癌细胞株CXCR4的mRNA表达,筛选出表达最高的A549细胞;将CRAd-CXCR4-GFP和Ad-NULL分别转染A549细胞,检测两者转染后CXCR4启动子活性和腺病毒复制数;将CRAd-CXCR4-GFP和Ad-NULL分别转染A549细胞和16HBE细胞,流式细胞术检测各组细胞凋亡情况,CCK-8检测各组细胞活性。结果:成功构建重组质粒pDC316-CXCR4-GFP,与骨架质粒pBHG-lox-E1,3Cre共转染293细胞后第11天可见片状绿色荧光;PCR表明目的基因CXCR4-E1A已成功整合在重组腺病毒基因组中;测定重组腺病毒滴度为1×1013PFU/L;CRAd-CXCR4-GFP转染A549细胞后E1A的mRNA和E4表达较Ad-NULL组明显上升;与Ad-NULL组和空白对照组相比,CRAd-CXCR4-GFP组前4dA549细胞凋亡率和活性无明显差异,第5天细胞凋亡率明显增加,细胞活性明显降低,各组间5d内16HBE细胞的细胞凋亡率和细胞活性均无明显变化。结论:成功构建条件复制型腺病毒表达载体CRAd-CXCR4-GFP,该载体对肺癌细胞具有靶向杀伤作用。     

携带IL-12的增殖腺病毒对鼻咽癌细胞的杀伤作用

目的：肿瘤选择性增殖腺病毒携带小鼠白细胞介素12（mIL-12)基因,增强对鼻咽癌细胞的杀伤作用。方法：用非增殖腺病毒Ad-LacZ测定腺病毒对鼻咽癌细胞CNE3和915的转染率,用E1B－55000u蛋白缺失的腺病毒dl1520和E1B－55000u蛋白缺失的腺病毒CNHK200－mlIL12分别转染培养的CNE3和915,并瘤内注射到裸鼠皮下的CNE3移植瘤。结果：Ad-LacZ病毒数量与细胞数量之比（MOI）为100时,转染率分别为63％和56％;MOI为10时,分别为12％和8％。 在体外不加入淋巴细胞的条件下,CNHK200－mIL和dl1520在MOI为100时都可在7d内完全杀灭鼻咽癌细胞CNE3和915。对裸鼠CNE3移植瘤,CNHK200－mil12治疗组疗效显著高于dl1520治疗组（P＜0．05） ,表明在选择性腺病毒中插入mIL12增强了其杀伤功能。结论：选择性增殖腺病毒携带mIL12后能够增强病毒对鼻咽癌细胞的杀伤作用,为鼻咽癌临床治疗探索一种新的基因病毒治疗方法。     

腺病毒介导的CD-TK融合基因联合GCV和/或5-Fc对人膀胱癌细胞的杀伤作用

目的：研究腺病毒介导的CD—TK融合基因联合前体药物对人膀胱癌细胞的杀伤作用。方法：利用含有CD—TK融合基因及绿色荧光蛋白（GFP）基因的复制缺陷腺病毒转染人膀胱癌细胞株T-24细胞,GFP表达可作为转染是否成功的间接标志,PCR扩增后琼脂糖凝胶电泳检测转染后细胞CD及TK基因序列的表达情况。用丙氧鸟苷（GCV）和／或5氟胞嘧啶（5-FC）,作为前体药物,以四甲基偶氮唑蓝（MTT）法检测其对转染后T-24细胞的杀伤作用及旁观者效应。结果：腺病毒在体外能高效转染T-24细胞,72h转染效率可接近100％。GCV和／或5-FC均能有效杀伤转染后膀胱癌细胞,给予相同浓度前体药物时,联合用药组显示出较强的肿瘤杀伤作用。0．5mg／ml GCV、0．1mg／ml 5-Fc和GCV＋5-Fc作用于转染后T-24细胞72h细胞生存率分别为23．30％、20．63％、10．10％。旁观者效应杀伤实验表明5-Fc组较GCV旁观者效应明显,而联合用药组显示出更强的旁观者效应。利用Hoechst-PI双染色法检测经前体药物作用后转染细胞,各组均可见凋亡细胞,但联合用药组凋亡细胞较单一用药组多。结论：CD—TK融合基因联合应用GCV和／或5-Fc能有效杀伤膀胱肿瘤细胞,并存在较强的旁观者效应,其杀伤机制可能与凋亡相关,为适用于人膀胱癌的治疗提供一条新思路。     

端粒酶催化亚单位基因启动子调控Hsv-tk/GCV系统对肺癌细胞A549选择性杀伤作用的研究

目的研究人端粒酶催化亚单位(human telomerase catalytic subunit,hTERT)基因启动子调控单纯疱疹胸苷激酶/更昔洛韦(herpes simplex virus-thymidine kinase/ganciclovir,Hsv-tk/GCV)治疗系统对人肺癌细胞株A549的选择体外杀伤作用。方法(1)用脂质体法将hTERT启动子和sv40启动子调控的tk基因表达质粒(pGL3-hTp-tk和pGL3-sv40-tk)转染端粒酶阳性的人肺腺癌细胞株A549及端粒酶阴性的人胚肺成纤维细胞株MRC-5,用逆转录-PCR方法检测转染细胞中tk基因的表达情况;(2)用MTT法检测GCV对上述转染细胞体外增殖的抑制作用;(3)用流式细胞仪检测GCV对上述转染细胞凋亡和细胞周期的影响。结果(1)转染pGL3-sv40-tk的细胞A549、MRC-5和转染pGL3-hTp-tk的A549均有tkmRNA表达,转染pGL3-hTp-tk的MRC-5无tkmRNA表达;(2)GCV对转染pGL3-sv40-tk的细胞A549、MRC-5和转染pGL3-hTp-tk的A549体外增殖均有明显抑制作用,对转染pGL3-hTp-tk的MRC-5无明显抑制作用;(3)转染pGL3-sv40-tk的A549、MRC-5和转染pGL3-hTp-tk的A549细胞,GCV处理后细胞凋亡指数(21.58%、9.35%和23.19%)均显著高于转染pGL3-hTp的A549和MRC-5细胞(0.78%和0.55%)及空白对照A549和MRC-5细胞(2.17%和0.60%),转染pGL3-hTp-tk的MRC-5细胞凋亡指数(0.88%)无明显升高。结论hTERT启动子调控Hsv-tk基因可以在肺癌细胞中选择性表达,hTERT调控的Hsv-tk/GCV治疗系统对肺癌细胞体外增殖具有靶向性抑制作用。     

上调miR-125b靶向Foxp3调控免疫因子表达增强宫颈癌细胞的放射敏感性

目的:探讨miR-125b对宫颈癌细胞放射敏感性的影响及其可能的下游机制研究。方法:实时荧光定量聚合酶链反应(quantitative real-time PCR,RT-qPCR)检测宫颈癌组织和细胞中miR-125b和Foxp3的表达量。HeLa细胞进行梯度剂量X射线(0、2、4、6 Gy)照射后,RT-qPCR检测...     

氟脲嘧啶诱导Egr-1启动子转录调控Flt3配基的基因表达

目的:探讨5-氟脲嘧啶(5-Fu)诱导Egr-1启动子调控造血生长因子基因表达对化疗后造血损伤的恢复作用.方法:构建携带Egr-1调控序列启动的Flt3 配基(FL)和EGFP双顺反子基因pCIneo真核表达载体(Egr-EF);通过脂质体转染骨髓基质细胞系HFCL并称为HFCL/EF;采用流式细胞术和倒置荧光显微镜观察EGFP绿色荧光表达的阳性细胞;采用RT-PCR、 Western blot和ELISA检测5-Fu对HFCL/EF细胞FL表达的影响;流式细胞术检测经5-Fu处理的HFCL/EF细胞上清对CD34 +细胞和CFU-GM的增殖作用;采用活性氧抑制剂N-乙酰半胱氨酸鉴定化疗通过活性氧诱导Egr-1启动子CArG序列调控下游基因表达的特异性.结果:构建了Egr-1调控序列启动的双顺反子基因表达载体(Egr-EF);经5-Fu处理后HFCL/EF细胞培养上清液较未加5-Fu组的FL含量明显增高并且对CD34 +细胞和CFU-GM具有较强的扩增作用( P <0.01);在5-Fu处理的HFCL/EF细胞中, EGFP活性、 FL mRNA和FL蛋白表达增强, 而且, N-乙酰半胱氨酸明显减少FL含量.结论:5-Fu诱导Egr-1启动子调控的造血生长因子基因表达对化疗药物处理后的造血损伤具有一定的恢复作用.     

Apoptotic effects of Tian-Long compound on endometrial adenocarcinoma cells in vitro

The Tian-Long (TL) compound is a water-soluble extract of six Chinese medicinal herbs. To explore its antitumor properties and the mechanism for activity in gynecological malignancies, the present studies were carried out using Ishikawa cells derived from uterine endometrial adenocarcinoma. Morphologically, cell death and decrease in the number of viable cells were observed in the presence of the TL compound. The proliferation of Ishikawa cells was significantly suppressed in a time- and dose-dependent manner, as indicated by both the WST-1 and the BrdU incorporation assay. Results from both the WST-1 and the BrdU incorporation assay demonstrated that the compound could inhibit the cell proliferation despite the presence of 17β-estradiol in the medium. It is generally noted that the disturbance in mitochondrial function and DNA synthesis during cell proliferation can result in apoptosis. Being consistent with this notion, redistribution of the plasma membrane phosphatidylserine was identified with fluoromicroscopy and flow cytometry. Analysis of the fluorescent patterns of JC-1 staining revealed depolarization of the mitochondrial membrane in the exposed cells. Moreover, the amount of Bcl-2 enhanced in the presence of 17β-estradiol was repressed by the compound. The present results indicate that the ingredients of TL compound are very promising for use in the treatment of endometrial adenocarcinoma. Further studies are necessary to elucidate the therapeutic mechanisms in its antitumor activity.     

人Egr-1启动子的克隆及其在肿瘤细胞中的辐射诱导反应

目的:克隆人Egr-1基因的启动子, 插入荧光素酶报告基因载体中, 并检测电离辐射对其活性的影响.方法:采用PCR技术从人乳腺癌细胞系MCF-7基因组中扩增出Egr-1启动子, 将其克隆到pGL3-basic载体中;将重组质粒转染人肿瘤细胞, 测定Egr-1启动子在不同辐射条件下转录活性的改变.结果:成功构建了Egr-1启动子的荧光素酶报告基因;在不同剂量的γ射线照射后, Egr-1的启动子活性均明显高于未照射组;在同一剂量照射后48 h, Egr-1的启动子活性达峰值.结论:本实验构建的Egr-1启动子具有辐射激活的功能, 为进一步研究放射-基因治疗奠定了基础.     

CIAPIN1在人肺癌组织中的表达及其对人小细胞肺癌NCI-H446细胞生长的影响

目的:探讨新基因CIAPINl在人肺癌和癌旁正常组织中的表达差异及该基因导人对人小细胞肺癌NCI-H446细胞生长的调控作用.方法:采用免疫组化方法检测51例石蜡包埋的肺癌及癌旁正常肺组织中CIAPIN1蛋白的表达;构建腺病毒载体介导CIAPIN1基因(Ad-CIAPIN1),转染到自身CIAPIN1低表达的人小细胞肺癌细胞系NCI-H446,Westernblot检测目的蛋白的表达;台盼蓝染色计数活细胞数,绘制细胞生长曲线;流式细胞术(FCM)分析细胞周期及细胞凋亡的变化.结果:癌旁正常肺组织中CIAPIN1基因蛋白阳性表达率(100%)明显高于肺癌组织中表达率(39.2%,P<0.05);与对照组相比,腺病毒介导的CIAPIN1实验组能迅速抑制NCI-H446细胞的生长(P<0.01),诱导细胞发生凋亡,并出现明显的G1/S期阻滞现象.结论:肺癌组织中CIAPIN1基因表达下调可能与肺癌发生密切相关,Ad-CIAPIN1转染NCI-H446细胞能明显抑制肿瘤细胞的生长,提示CIAPINI基因可能是一个新的抑癌相关基因.     

The effects of TATA-box in CYC1 promoter on the reporter gene regulated by ERE in the recombinant yeast cell

The complementary oligonucleotides, each with two consensus estrogen response element (ERE)-sequences and 5'-Hind III and 3'-Sph I sticky ends were artificially synthesized. A solution with both the complementary DNA sequences was heated to 95'C and cooled down to room temperature to form double strand DNA (dsDNA). The set was cloned into the corresponding sites of CYC1 promoter of the pERE-CYC-yEGFP to yield pERE-CYCalpha-yEGFP vector. The two different reporter vectors, pERE-CYC-yEGFP and pERE-CYCalpha-yEGFP, the 2ERE, were placed in the CYC1 promoter. The former promoter downstream ERE contains alpha and beta-TATA boxes and the latter has only alpha-TATA box. The two different reporter vectors were transformed into the yeast cells that express human estrogen receptor alpha (ERalpha). Incubation of the recombinant yeasts with the six estrogenic compounds for 4 hours showed that the recombinant cell containing pERE-CYCalpha-yEGFP would give very poor dose-response curves, in contrast to the recombinant cell containing pERE-CYC-yEGFP which produced well-shaped dose-response curves. So it is necessary for this bioassay that alpha and beta-TATA boxes in the minimal CYC1 promoter when the promoter is used as a rapid and high throughput system for screening estrogenic chemical products.     

Analysis of orthologous gene expression between human pulmonary adenocarcinoma and a carcinogen-induced murine model

Human adenocarcinoma (AC) is the most frequently diagnosed human lung cancer, and its absolute incidence is increasing dramatically. Compared to human lung AC, the A/J mouse-urethane model exhibits similar histological appearance and molecular changes. We examined the gene expression profiles of human and murine lung tissues (normal or AC) and compared the two species' datasets after aligning approximately 7500 orthologous genes. A list of 409 gene classifiers (P value <0.0001), common to both species (joint classifiers), showed significant, positive correlation in expression levels between the two species. A number of previously reported expression changes were recapitulated in both species, such as changes in glycolytic enzymes and cell-cycle proteins. Unexpectedly, joint classifiers in angiogenesis were uniformly down-regulated in tumor tissues. The eicosanoid pathway enzymes prostacyclin synthase (PGIS) and inducible prostaglandin E(2) synthase (PGES) were joint classifiers that showed opposite effects in lung AC (PGIS down-regulated; PGES up-regulated). Finally, tissue microarrays identified the same protein expression pattern for PGIS and PGES in 108 different non-small cell lung cancer biopsies, and the detection of PGIS had statistically significant prognostic value in patient survival. Thus, the A/J mouse-urethane model reflects significant molecular details of human lung AC, and comparison of changes in orthologous gene expression may provide novel insights into lung carcinogenesis.