基于双荧光系统的HepG2肝细胞癌原位移植裸鼠模型建立及活体荧光成像动态定量分析

目的:建立一种可以实时、定量、动态监测的肝细胞癌原位移植模型,并利用活体荧光成像系统对裸鼠体内原位肝细胞癌生长进行分析。方法:利用慢病毒包装系统包装pCDH-GFP-Luc质粒,将绿色荧光蛋白(GFP)和萤光素酶(Luc)基因通过病毒感染的方式整合到HepG2肝癌细胞染色体中,利用流式细胞术分选GFP+细胞,扩增培养后,将该细胞注射到裸鼠皮下进行成瘤,成瘤后分离肿瘤组织接种裸鼠肝脏,将造模成功的裸鼠分为对照组和治疗组,分别灌胃给与0.5%羧甲基纤维素钠(CMC-Na)和50 mg/kg索拉非尼,2/d,连续28 d,每7 d利用活体荧光成像系统观察肝癌细胞在对照组和治疗组裸鼠肝脏内的生长情况。实验结束后,分离裸鼠肝脏肿瘤,拍照称重。结果:建立了稳定表达双荧光的人肝癌细胞系HepG2-GFP-Luc,体外发光强度与表达萤光素酶的细胞数量呈正相关(R2=0.9945);建立了肝细胞癌原位移植活体荧光成像模型,对照组和治疗组肝脏内肿瘤细胞荧光强度随时间的延长逐渐增加,治疗组荧光强度明显低于对照组。定量分析结果显示,在第24、31和38 d,治疗组荧光总光子数值显著低于对照组;治疗组平均瘤重显著低于对照组。结论:建立了一种肝细胞癌原位移植荧光成像模型,可通过活体成像系统对肿瘤大小进行动态定量分析,为抗肝癌药物的药效学评价提供了实时定量分析动物模型。     

携带荧光素酶基因肝癌细胞株的构建及在肝癌原位移植瘤模型中应用

[目的]构建稳定表达荧光素酶基因的人肝癌细胞株,建立可实时观察的肝癌原位移植瘤模型。[方法]构建含有萤光素酶基因的慢病毒载体,利用慢病毒三质粒系统磷酸钙共转染HEK 293T细胞,收集纯化病毒感染肝癌细胞SMMC7721,嘌呤霉素(puromycin)结合有限稀释法筛选稳定转导细胞株,将细胞原位注射裸鼠肝组织,建立原位肝癌动物模型。[结果]包装纯化的慢病毒悬液的滴度为8.4×106TU/m L,感染肝癌细胞后成功筛选到稳定表达的肝癌细胞株。利用该细胞株成功建立原位注射肝癌裸鼠模型,经活体荧光成像系统观察到肝癌细胞在活体动物体内的分布情况。[结论]荧光素酶肝癌细胞株的成功构建及利用该细胞株建立的原位移植瘤肝癌动物模型为肝癌的治疗研究奠定了基础。     

活体荧光成像对裸鼠肝癌细胞系MHCC97-H原位移植模型的动态量化分析

目的:利用生物自发光的裸鼠肝癌原位移植模型,以活体荧光成像技术对肝癌的生长和转移情况进行动态、量化分析.方法:将稳定转染了荧光素酶(luciferase)基因的人肝癌细胞株MHCC97-H-LUC细胞,移植至裸鼠肝脏包膜下,每周利用活体荧光成像系统对裸鼠体内移植瘤的生长部位和范围进行成像,测量肿瘤细胞生物发光量,动态观察肝癌细胞在裸鼠体内的肿瘤数量、生长速度和转移情况.结果:建立可稳定表达荧光素酶的人肝癌细胞株MHCC97-H-LUC并用于进行生物自发光的裸鼠原位移植模型;利用活体荧光成像系统对裸鼠体内的移植瘤成像,见发光部位由肝脏向腹腔扩散,发光量随时间呈指数级增长;病理学观察证实肿瘤细胞长.结论:利用活体荧光成像技术的动态量化分析可灵敏、准确地监测裸鼠肝癌原位移植模型中肿瘤细胞的生长及转移情况,为肿瘤发生、生长、转移机制及对抗肿瘤生长和转移的体内研究提供了科学的量化手段.     

荧光素酶标的人肝癌细胞裸鼠异种移植瘤模型的生物发光成像和PET-CT成像比较

目的利用荧光素酶基因标记的人肝癌细胞株BEL-7402建立裸鼠肝原位移植模型,及小鼠肝原位移植模型的生物发光和小动物PET-CT成像的比较。方法构建表达荧光素酶基因的真核表达载体并将其转入人肝癌细胞BEL-7402,经梯度浓度G418筛选获得稳定表达荧光素酶基因的细胞克隆并扩大培养。BALB/cA-nu裸鼠肝门静脉接种5×105个发光细胞使其成瘤,活体荧光成像和小动物PET-CT成像系统观察肿瘤的生长情况。结果获得了稳定表达Luc的人肝癌细胞株,将其接种到裸鼠体内,活体荧光成像系统观察发现能够成瘤,小动物PET-CT影像观察发现小鼠肝脏边缘对18 F-FDG有高摄取区域。结论利用荧光素酶基因标记的人肝癌细胞BEL-7402成功建立了原位肝癌裸鼠模型,小动物活体成像结合小动物PET-CT技术为原位肿瘤模型的建立提供了一种新的可靠的技术,为进一步研究肝癌生长转移机制和药物开发提供了新的有用工具。     

用于活体成像的小鼠肺癌移植瘤模型的建立

本研究旨在建立可用于活体成像的小鼠肺癌移植瘤模型。利用脂质体将荧光素酶表达载体pGL4.17(luc2/neo)转染至人非小细胞肺癌细胞株A549,经G418筛选获得稳定表达荧光素酶的细胞克隆。根据体外生物发光情况及细胞的生长特性,从中挑选合适克隆,进行裸鼠皮下接种,SCID鼠尾静脉接种,建立肺癌移植瘤模型。利用活体成像系统监测肿瘤的生长转移情况,并用切片HE染色进一步验证小鼠模型移植瘤的原位成瘤和转移能力。实验结果表明:本研究成功地构建了可用于活体成像的小鼠肺癌移植瘤模型,模型稳定可靠、直观、灵敏,为肿瘤生长转移机制的研究及抗肿瘤药物的研发提供了重要工具。     

人胰腺癌裸鼠异种移植瘤模型的生物发光成像和超声成像比较

目的利用荧光素酶基因标记的人胰腺癌细胞株Capan-2建立胰腺癌裸鼠移植模型,评价生物发光和小动物超声成像在移植瘤模型建立中的作用。方法将表达荧光素酶基因的真核表达载体转入人胰腺癌细胞Capan-2,将1×106人胰腺癌细胞悬液分别接种于裸鼠胰腺和右后肢皮下,使其成瘤。生物发光成像和小动物超声成像系统观察肿瘤的生长情况。结果肿瘤细胞原位移植成功率为75%,皮下移植成功率为100%。生物发光成像系统在肿瘤细胞原位接种第7天,可以观察到肿瘤发光;小动物超声成像系统在肿瘤细胞皮下接种第7天,可以测量肿瘤的大小,但在肿瘤细胞原位接种的第7天不能测量肿瘤的大小。另外肿瘤细胞在裸鼠皮下生长的速度比原位生长速度快3倍左右。结论生物发光成像系统更适用于肿瘤早期监测,为深入研究胰腺癌的发生发展、侵袭转移机制提供理想工具。     

SW1990和Capan-2红色荧光标记胰腺癌移植肿瘤模型的建立和比较

目的建立稳定表达红色荧光蛋白基因的人胰腺癌细胞系,为体内监测肿瘤的早期生长及抗肿瘤药物的药效评价建立一种新的肿瘤动物模型。方法以Lipofectamine 2000介导chickenβ-actin-RFP-NEO转染人胰腺癌细胞SW1990和Capan-2,经梯度浓度G418筛选获得稳定表达红色荧光蛋白的细胞克隆并扩大培养。BALB/cA-nu裸鼠皮下接种1×106个发光细胞使其成瘤,活体荧光成像系统观察肿瘤的生长情况。结果获得了稳定表达RFP的两种不同的人胰腺癌细胞株,将其接种到裸鼠体内可成瘤,利用活体成像系统观察了肿瘤的生长动态过程,并且SW1990肿瘤细胞的生长速度较Capan-2细胞快。结论用红色荧光蛋白标记的人胰腺癌细胞建立的裸鼠肿瘤模型为胰腺癌的研究和相关药物筛选提供了可进行荧光影像活体、动态分析的动物模型。     

人结肠腺癌细胞HCT－8绿色荧光标记肿瘤模型的建立

目的筛选表达绿色荧光蛋白基因的人的单克隆结肠腺癌细胞系,为体内监测肿瘤的早期生长建立一种新的肿瘤动物模型。方法以脂质体2000介导chicken β－acfin-GFP—NEO转染人结肠腺癌细胞HCT－8,经梯度浓度G418筛选获得稳定表达绿色荧光蛋白的细胞克隆并扩大培养。BALB／CA－nu裸鼠皮下接种1×10^6个发光细胞使其成瘤,活体荧光成像系统观察肿瘤的生长情况。结果获得了稳定表达GFP的人结肠腺癌细胞株,将其接种到裸鼠体内可成瘤,利用活体成像系统观察了肿瘤的生长过程,肿瘤的发光随着观察时间的延长而增加。结论绿色荧光蛋白能够在人结肠腺癌细胞HCT-8中长期稳定表达,用绿色荧光蛋白标记的人结肠腺癌细胞HCT-8建立的裸鼠肿瘤模型为进一步研究结肠肿瘤和相应的药物筛选提供了一种简便、可行的新方法。     

电转系统介导的荧光素酶稳定表达PANC-1细胞的构建及其生物发光成像检测

在构建稳定表达荧光素酶的人胰腺癌PANC-1细胞的基础上,建立适合活体成像研究的胰腺癌动物模型,为深入研究胰腺癌发病机制打下基础。该研究运用Lonza NucleofectorTM核转染系统将携带有荧光素酶基因(firefly luciferase,luc)的质粒(GV258)稳定转染PANC-1细胞,利用嘌呤霉素筛选出能稳定表达荧光素酶的细胞株PANC-1-LUC,并应用活体成像系统对其体内外生物发光进行检测。进一步构建PANC-1-LUC裸鼠皮下移植瘤,同样方法接种慢病毒载体构建的PANC-1-luc细胞作为对照,观察成瘤率、瘤体积,检测生物发光强度。体内外生物发光检测结果均显示,光通量值与细胞数之间呈显著的直线相关(P0.01)。PANC-1-LUC细胞皮下接种裸鼠,1周成瘤率即达80%以上,瘤体积可达平均100 mm3。观察6周,裸鼠皮下肿瘤生长符合Gompertzian曲线。每周的生物发光检测结果均显示,PANC-1-LUC移植瘤的光强度与瘤体积有显著的线性关系(P0.05)。以上结果说明,该文所构建的PANC-1-LUC细胞株能够稳定、长期地表达荧光素酶,更适合构建活体成像研究的裸鼠胰腺癌模型。     

慢病毒介导荧光素酶表达的人鼻咽癌细胞小鼠模型的建立

目的：建立荧光素酶标记的人鼻咽癌细胞裸鼠模型,活体成像系统监测肿瘤的生长并与肿瘤的体积进行对比。方法：构建表达荧光素酶基因2（1uc2）的慢病毒载体,与辅助质粒共转染293T细胞以制备慢病毒,感染人鼻咽癌SUNEl细胞后经嘌呤霉素筛选获得表达luc2的细胞株。活体成像设备体外检测不同数量细胞的发光强度,最后以5×10 6个细胞皮下接种BALB／cnu／nu裸鼠,活体成像系统动态记录接种后肿瘤的信号并与肿瘤的体积对比。结果：成功构建慢病毒表达质粒pLenti．1uc2并包装出慢病毒颗粒,病毒感染后嘌呤霉素筛选6天得到鼻咽癌细胞株SUNEl一luc2。细胞株传代后有稳定的发光强度,且经活体检测的每秒光子数与细胞数成正相关（R2=0．96）;活体成像观察发现裸鼠接种第2天接种部位的发光强度就达到3-2×10^8,而且成瘤过程中发光强度的变化与肿瘤大小一致。结论：成功构建适用于活体成像的人鼻咽癌SUNEl细胞的裸鼠成瘤模型,该模型从细胞接种开始即可有效动态监测鼻咽癌皮下瘤的生长及转移,从而为鼻咽癌的成瘤机制及药物干预研究提供一个新的手段。     

间充质干细胞双标记光学成像的体内试验研究

目的:验证双标记生物发光成像活体观测MSCs在肝癌裸鼠模型向肿瘤病灶的趋化作用的可行性。方法:应用fluorescence(荧光)与bioluminescence(生物发光)两种成像方法,对MSCs进行CM-Di I荧光标记及对人肝癌细胞Hep G2进行Fluc-慢病毒感染并由此建立裸鼠肝癌模型,构建双标记成像系统,应用精诺真小动物光学成像仪在裸鼠肝癌模型中观测间充质干细胞向肿瘤的趋化作用。结果:在鼠尾静脉注射标记MSCs细胞后21天荧光成像可见MSCs主要积聚于肿瘤病灶处及肝脏。生物发光成像后可监测到病灶处由luciferase标记肿瘤细胞(Hep G2)发出荧光;将荧光成像与生物发光成像所得图像经后处理融合后,可见证间充质干细胞像肿瘤病灶定向迁徙的生物过程。经肿瘤病理切片证实间充质干细胞成功迁徙至肿瘤病灶中。结论:应用间充质干细胞双标记光学成像系统实现MSCs在活体内对肿瘤的趋化过程进行观测是可行的。这种成像方法可作为下一步以MSCs为载体的肿瘤基因治疗的有效监测手段。     

Bioluminescent imaging of hepatocellular carcinoma in live mice

A non-invasive orthotopic hepatocellular carcinoma (HCC) model was created with human HCC cells (HepG-Luc) constitutively expressing luciferase (Luc) in nude mice. Development of tumor growth and response to anti-tumor therapy combined with 5-fluorouracil and cisplatin was monitored by whole-body bioluminescent imaging (BLI). Luciferase activity in the tumor, determined by BLI, correlated with the tumor volume and weight. The anti-tumor therapy proved effective by BLI monitoring. In conclusion, BLI by luciferase provides a non-invasive method of monitoring tumor activities that can prove useful for therapeutic intervention studies.     

抗VEGFR-2嵌合Fab抗体对裸鼠肝癌原位移植瘤新生血管生成的影响

目的:检测抗VEGFR-2嵌合Fab抗体对裸鼠肝癌原位移植瘤血管生成的影响.方法:建立裸鼠肝癌H22细胞原位移植瘤模型,随机分成生理盐水组(n=12)和抗体组(n=12).采用免疫组织化学SP染色法对两组肝脏移植瘤进行血管染色,观察其微血管密度(MVD)情况.结果:成功建立裸鼠H22肝癌原位移植瘤模型,HE染色显示肝脏移植瘤为肝细胞肝癌,免疫组化结果显示肝脏实体瘤内微血管密度抗体组较生理盐水组显著性减少(25.64± 1.53 vs 8.65± 1.79,P＜0.05).结论:抗VEGFR-2嵌合Fab抗体能够抑制裸鼠肝癌原位移植瘤的血管生成.     

盐霉素抑制人肝细胞癌转移与侵袭的体外与体内实验研究

目的：肝癌的转移与复发是肝癌治疗的一大难题,盐霉素是近年来新发现的具有抗肿瘤作用的抗生素,本文研究了盐霉素在体外及体内对人肝细胞癌转移与侵袭能力的作用及机制。方法：在体外对肝癌细胞株HepG2,SMMC-7721,BEL-7402给予盐霉素处理,体内建立裸鼠肝脏原位肿瘤模型,并给予腹腔注射盐霉素治疗。观察肿瘤细胞的转移侵袭能力以及肝内肿瘤转移灶的情况,进一步测定E．cadherin,Vimentin的表达,来研究盐霉素对肝癌转移及侵袭能力的影响及机制。结果：经盐霉素处理后,肝癌细胞株HepG2,SMMC．7721,BEL．7402的转移及侵袭能力明显下降,肝内转移灶的数目也减少。分子机制检测发现盐霉素处理后E．cadherin表达增高,Vimentin表达下降。结论：盐霉素在体内与体外都抑制了肝癌的转移与侵袭,其机制可能抑制了肿瘤细胞的上皮间质化（EMT）过程。这为控制肝癌的转移和复发提供了新的治疗思路。     

利用Gaussia萤光素酶建立乳腺癌实时定量检测动物模型

目的：建立-种基于分泌型萤光素酶的实时定量检测实验动物体内肿瘤大小的方法。方法：以分泌型Gaussia萤光素酶（Gluc）为报告基因,以嘌呤霉素为筛选基因,将两者用T2A元件连接后克隆到慢病毒载体,包装慢病毒后感染乳腺癌MCF-7细胞,经嘌呤霉素筛选得到稳定转染细胞MCF-7-Gluc,并检测细胞上清中Gluc活性随时问和细胞数目的变化;将MCF-7-Gluc扩大培养后经皮下注射到雌性BALB／c裸鼠前肢腋下,待肿瘤形成后,检测外周血液中Gluc活性与肿瘤体积的相关性。结果：体外实验显示稳定转染细胞MCF-7-Gluc分泌到细胞上清的Gluc活性与时间和细胞数量在-定范围内均呈现良好的线性关系,体内实验显示裸鼠血液中的Gluc活性与肿瘤体积呈正相关。结论：Gluc技术可作为-种灵活、方便、实时定量检测活体动物体内肿瘤大小的有效工具。     

人卵巢癌裸鼠移植实体瘤模型的建立

目的建立人卵巢癌裸鼠移植实体瘤模型。方法将1例人卵巢癌组织移植裸鼠,建立人卵巢癌裸鼠原代移植实体瘤模型的基础上,再将实体瘤皮下移植、实体瘤原位移植、实体瘤细胞移植裸鼠。观察裸鼠实体瘤生长和转移情况,称量其体重、子宫卵巢重、瘤重及瘤的大小,并作病理、电镜、染色体检查。结果成功地建立人卵巢癌裸鼠移植实体瘤模型,并已传至第18代,传代移植成功率100％,组织学和超微结构形态均证明该实体瘤保留了原人卵巢癌特征,有人卵巢癌染色体特征,并出现肝、脾转移。结论本研究建立人卵巢癌裸鼠移植实体瘤模型与人相似,通过18代传代和实验观察方法稳定可靠。为人卵巢癌的研究提供了理想的动物模型。     

Time course of bioluminescent signal in orthotopic and heterotopic brain tumors in nude mice

In vivo bioluminescence imaging is becoming increasingly popular. Quantification of bioluminescence signals requires knowledge of the variability and reproducibility of this technique. The objective of this study was to analyze the time course of luminescent signal emitted from firefly luciferase-expressing tumors in two locations, following luciferin injection and at different times after tumor cell implantation. Knowledge of the kinetics of the bioluminescent signals is required for the reliable quantification and comparison of signal during longitudinal studies. The kinetics of bioluminescence was evaluated in orthotopic and heterotopic brain tumors in mice using a human brain tumor cell line constitutively expressing luciferase. Tumor cells were implanted in the brains and flanks of the animals, and whole-body images revealing tumor location were obtained. Tumor burden was monitored over time by the quantitation of photon emission. The magnitude of bioluminescence measured in vivo varied with time after the injection of luciferin, as well as with dose, which necessitated that the comparison of the quantitative results take into consideration the time after injection. Heterotopic and orthotopic tumors exhibited significantly different time courses; however, time after implantation as characterized by kinetic studies performed on days 4 and 14 after cell implantation revealed no significant differences in orthotopic tumors. Future quantitative longitudinal studies must take into account the differences in the kinetics of different models.     

Conditionally replicating adenovirus expressing TIMP2 increases survival in a mouse model of disseminated ovarian cancer

Ovarian cancer remains difficult to treat mainly due to presentation of the disease at an advanced stage. Conditionally-replicating adenoviruses (CRAds) are promising anti-cancer agents that selectively kill the tumor cells. The present study evaluated the efficacy of a novel CRAd (Ad5/3-CXCR4-TIMP2) containing the CXCR4 promoter for selective viral replication in cancer cells together with TIMP2 as a therapeutic transgene, targeting the matrix metalloproteases (MMPs) in a murine orthotopic model of disseminated ovarian cancer. An orthotopic model of ovarian cancer was established in athymic nude mice by intraperitonal injection of the human ovarian cancer cell line, SKOV3-Luc, expressing luciferase. Upon confirmation of peritoneal dissemination of the cells by non-invasive imaging, mice were randomly divided into four treatment groups: PBS, Ad-ΔE1-TIMP2, Ad5/3-CXCR4, and Ad5/3-CXCR4-TIMP2. All mice were imaged weekly to monitor tumor growth and were sacrificed upon reaching any of the predefined endpoints, including high tumor burden and significant weight loss along with clinical evidence of pain and distress. Survival analysis was performed using the Log-rank test. The median survival for the PBS cohort was 33 days; for Ad-ΔE1-TIMP2, 39 days; for Ad5/3-CXCR4, 52.5 days; and for Ad5/3-CXCR4-TIMP2, 63 days. The TIMP2-armed CRAd delayed tumor growth and significantly increased survival when compared to the unarmed CRAd. This therapeutic effect was confirmed to be mediated through inhibition of MMP9. Results of the in vivo study support the translational potential of Ad5/3-CXCR4-TIMP2 for treatment of human patients with advanced ovarian cancer.     

Inhibitory effects of cocoa tea (Camellia ptilophylla) in human hepatocellular carcinoma HepG2 in vitro and in vivo through apoptosis

Cocoa tea (Camellia ptilophylla), a naturally decaffeinated tea commonly consumed as a healthy beverage in southern China, has been recently found to be a potential candidate for the treatment of different diseases, including obesity and cancers. The present study aimed to evaluate the anti-liver cancer activities of green cocoa tea infusion (GCTI) in vitro and in vivo using human hepatocarcinoma cell line HepG2 cells and nude mice xenograft model. The apoptotic activities of GCTI were assessed using flow cytometry, Western blotting and immunohistochemical analysis. Our results showed that GCTI significantly inhibited the proliferation of HepG2 cells in a dose-dependent manner (IC(50) values=292 μg/ml at 72 h). GCTI induced HepG2 cells to undergo apoptosis, which was demonstrated by cell cycle analysis and annexin-V and propidium iodide staining. The caspase cascade was activated as shown by significant proteolytic cleavage of caspase-3 and PARP in GCTI-treated cells in a dose- and time-dependent manner. In addition, GCTI increased the expression of cell cycle inhibitory proteins (p21, p27 and p53) and the Bax-to-Bcl-2 ratio to induce apoptosis. The antiproliferative effect of GCTI was confirmed in HepG2 xenograft nude mice. The tumor growth was effectively inhibited by GCTI in a dose-dependent manner as indicated by the decrease in tumor volume and tumor weight after 4 weeks of treatment. Administration of GCTI increased terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling and caspase-3-positive cells in the tumor section. In conclusion, these results revealed that GCTI may be a potential and promising agent of natural resource to treat liver cancer.