原位红色荧光标记骨肉瘤肺转移裸鼠模型的建立

目的 利用红色荧光蛋白（RFP）基因建立原位骨肉瘤肺转移裸鼠模型,为体内监测骨肉瘤的生长及抗肿瘤药物的药效评价建立一种肿瘤动物模型。方法 以包含逆转录病毒pLNCX DsRed 2的PT67包装细胞转染人骨肉瘤细胞系143B,在裸鼠胫骨近端原位接种使其成瘤,活体荧光成像系统观察骨肉瘤的生长及肺转移情况。结果 获得稳定表达红色荧光蛋白的人骨肉瘤细胞株,原位接种的肿瘤发生率达100％,肺转移率为80％。通过活体荧光成像系统于移植1周观察到肿瘤形成,移植4周肿瘤呈梭形膨胀,移植6周肿瘤呈分叶状球形,发光强度亦逐渐增加。结论 通过建立原位骨肉瘤肺转移裸鼠模型可以观察原位骨肉瘤的不同生长过程以及肺转移情况,是研究骨肉瘤生长及肺转移相关因素的一种重要工具。     

人骨肉瘤原位移植模型的建立及生物学特征

目的 用人骨肉瘤细胞系HOS-98建立人骨肉瘤裸鼠胫骨原位移植模型,以探讨宿主器官微环境对人骨肉瘤细胞侵袭及转移等生物学行为的影响。方法 将人骨肉瘤细胞系HOS-98接种于裸鼠皮下,形成移植瘤,用传代移植瘤组织作为移植材料,进行胫骨原位移植及皮下移植。分别于移植后4周和8周处死小鼠,进行病理形态学检查,并对两种方法在成瘤率、生长方式及侵袭、转移等生物学行为比较。结果 两种移植方式在成瘤率及形态学上无明显不同,胫骨原位移植的潜伏期较短,并且生长快于皮下移植方式。皮下移植瘤呈局限性膨胀生长,有不完整的纤维包膜,瘤内类骨基质较少见,未见肺转移,观察8周时无明显消瘦;而胫骨原位移植瘤侵袭周围组织,可见发生肺转移,8周明显消瘦。原位移植的裸鼠血清ALP水平高于皮下移植者。原位移植的X线检查有明显的类似于人的骨性反应。结论 用人骨肿瘤细胞系HOS-98皮下接种的移植瘤作为移植材料是建立肿瘤异位移植的可行途径,裸鼠胫骨微环境较皮下组织更适合于人骨肉瘤的侵袭及转移表达,裸鼠胫骨原位移植模型的恶性生物学行为更接近临床骨肉瘤患者的体内侵袭及转移实际,该原位移植模型为今后的实验研究提供了更加接近患者实际的实验模型。     

完整瘤组织块原位移植法建立人成骨肉瘤转移模型

目的：建立人成骨肉瘤裸鼠转移模型。方法：采用完整瘤组织块原位移植法获得裸鼠自发性肺转移模型,并对转移模型进行影像学检查、组织学检查及ＰＣＲ同源性分析。结果：建立裸鼠体内人成骨肉瘤转移模型,其自发性肺转移率达到１００％,肝转移率达３０％。影像学检查及组织学检查均与人成骨肉瘤临床情况相似,ＰＣＲ同源性分析证实裸鼠肺部转移灶为人成骨肉瘤细胞。结论：裸鼠体内人成骨肉瘤自发性转移模型模拟了临床发病过程,对人     

拮抗凋亡转录因子基因在高转移人成骨肉瘤细胞系中的高表达

背景与目的：成骨肉瘤是青少年中最常见的恶性骨肿瘤,具有易发生肺转移的特点。尽管目前已能够成功地控制原发瘤,但是仍有30％以上的患者在5年内死于肺转移。更好地理解调节转移过程的分子机制,为设计有效的治疗方案提供生物学基础,我们用原位移植的方法建立了人成骨肉瘤细胞系SOSP－9607裸鼠转移模型,用这一模型筛选出了高转移细胞系SOSP－M。本研究旨在通过比较两个细胞系的基因表达水平来克隆与骨肉瘤转移相关的基因,探讨成骨肉瘤转移的分子机制。方法：采用抑制性消减杂交技术建立人成骨肉瘤高转移细胞株SOSP－M的消减文库;用差异筛选技术筛选出阳性克隆;对部分克隆进行测序和同源性分析,用Northern杂交后转录多聚酶链式反应技术对SOSP－M中表达上调的有意义的克隆在低转移细胞系SOSP－9607,OS－9901,高转移细胞系SOSP－M和裸鼠肺转移结节中的表达情况进行了分析。结果：在高转移细胞株SOSP－M中有2个阳性克隆均与人凋亡对抗转录因子（apoptosis antagonizing transciption factor)同源（99％同源）。Northern杂交及反转录PCR证实这个基因在高转移细胞和裸鼠肺转移结节中高表达,而在低转移人成骨肉瘤细胞系SOSP－9607和OS－9901中表达微弱。结论：对抗凋亡转录因子在促进肿瘤细胞转移中可能起重要作用。     

RNAi阻断CXCR4基因对胰腺癌AsPC-1细胞肺转移能力的影响

目的:观察针对CXCR4基因的RNAi(RNA interference)转染AsPC-1细胞后肿瘤细胞增殖、迁移、侵袭的情况及在裸鼠肺内血行转移的情况,探讨SDF-1/CXCR4在胰腺癌转移中的作用.方法:利用小发夹结构RNA作为载体设计针对人CXCR4基因的RNA干扰,利用慢病毒成功转染人胰腺癌细胞系AsPC-1细胞,然后分为转染组(LV-siCXCR4-1)、阴性对照组(AsPC-1-LV-con)和空白对照组(AsPC-1细胞),三组加入SDF-1α后采用MTT法检测细胞增殖,Transwell小室检测细胞迁移,体外侵袭实验检测细胞的体外侵袭能力,并将三组细胞注入已建立急性血行转移模型的裸鼠尾静脉,45天后观察裸鼠肺部转移结节和肺脏组织,计数肿瘤转移结节的数目并进行HE染色.结果:SDF-1α可促进阴性对照组和空白对照组细胞增殖、迁移和体外侵袭.空白对照组和阴性对照组裸鼠可见大量肺转移结节,而转染组裸鼠未见明显肺转移结节.结论:CXCR4基因RNAi可显著抑制AsPC-1细胞增殖、体外迁移和侵袭及肺血行转移.CXCR4/SDF-1受体配体系统参与了胰腺癌的转移,通过RNAi干扰技术可抑制胰腺癌细胞的转移.     

IGF1受体的β亚基突变体对人骨肉瘤细胞增殖、迁移和凋亡的影响

目的 探讨IGF1受体（IGF-1R）的β亚基突变体（sb-IGF1R、ma-IGF1R）对骨肉瘤143B细胞生物学行为的影响。方法 设计与构建sb-IGF1R、ma-IGF1R片段,克隆到腺病毒AdEasy穿梭质粒中,获得Ad-sbIGF1R、Ad-maIGF1R,再将两者与Ad-GFP分别转染骨肉瘤细胞143B,观察细胞的增殖、迁移及凋亡情况;构建Ad-sbIGF1R、Ad-maIGF1R及Ad-GFP裸鼠皮下荷瘤模型,评价肿瘤在体外的生长情况。结果 通过质粒PCR验证,IGF-1Rβ亚基突变体在骨肉瘤细胞中过表达。与对照组相比,经Ad-sbIGF1R、Ad-maIGF1R处理过的骨肉瘤细胞,其细胞增殖、迁移能力显著抑制,促进了骨肉瘤细胞的凋亡。同时在裸鼠皮下荷瘤模型中抑制肿瘤生长。结论 IGF1受体的β亚基突变体抑制骨肉瘤细胞增殖和转移,并促进骨肉瘤细胞凋亡。     

经小动物内窥镜行肠黏膜下注射肿瘤细胞建立原位结直肠癌模型的技术探讨

目的:探讨使用活体小动物内窥镜进行原位注射人源性结肠癌细胞系建立原位结直肠癌模型的技术方法。方法:6~8周龄BALB/c雌性裸鼠20只,异氟醚气体持续麻醉,通过小动物结肠镜的引导,使用30G注射针将人结肠癌HCT-116细胞注射到裸鼠肠黏膜下,在肿瘤细胞注射3、7、10、15天进行小鼠内窥镜检查,观察裸鼠结直肠的成瘤情况。结果:利用小动物内窥镜行黏膜注射肿瘤细胞建立结直肠癌模型的技术成功率达100%。在注射肿瘤细胞时未出现穿孔,在小鼠内窥镜第7天随访时有1例裸鼠在肠镜通过肿瘤时出现肠壁穿孔。本研究中,没有出现因内窥镜注射导致的裸鼠死亡,所有19例存活裸鼠在第15天随访时均形成原位结直肠肿瘤,使用该方法建立裸鼠原位结直肠癌的建模成功率为95%。结论:通过小鼠内窥镜引导行肠黏膜下注射肿瘤细胞建立结直肠癌原位模型是一项快速而且有效的建模技术,该模型可更好地用于药物检测、基因功能评估和肿瘤转移。     

小鼠Lewis肺癌原位模型的构建

背景与目的肺癌原位模型包括小鼠自发性肺肿瘤模型和气道内接种模型等,但自发性肺肿瘤模型耗时较长且成瘤率不能保证,而气道内接种模型成瘤部位及大小不稳定。本研究以3LL细胞系细胞接种于C57BL/6小鼠肺原位,与皮下接种模型比较,探讨其稳定性、转移特性,并建立小鼠肺原位癌模型的优化方法。方法将不同数量级的3LL细胞分别直接接种于C57BL/6小鼠左侧腋下制备皮下接种模型和以Matrigel悬浮后接种于其左肺制备原位接种模型,观察两种模型的生存期,并对小鼠进行解剖后行病理切片检查、免疫组化染色检测微血管密度、流式细胞仪检测CD44v。结果皮下组成瘤率分别为100%、66.7%、16.7%,未见明显转移。原位组成瘤率分别为100%、100%、83.3%,并可转移至对侧胸廓及肺脏。原位组中位生存期(38d、35d、23d)明显少于皮下接种组(82d、72d、50d)。原位接种组微血管密度(120.2±9.73)高于皮下组(92.6±7.12)。原位接种组肿瘤细胞悬液CD44v表达(26.46±1.56)%高于皮下接种组(23.13±1.02)%。结论以3LL细胞接种于小鼠肺部所建立的肺癌原位模型简单可靠,重复性高,具有较...     

腺病毒介导人VEGF-siRNA对裸鼠移植骨肉瘤的抑制作用

目的: 研究腺病毒介导人VEGFsiRNA对裸鼠移植骨肉瘤的治疗作用。方法：利用腺病毒重组技术将VEGFsiRNA基因克隆入增殖缺陷型腺病毒基因组中，构建重组腺病毒AdVEGFsiRNA，重组腺病毒体外感染骨肉瘤MG63细胞，RT-PCR检测MG63细胞VEGF的表达水平。建立荷人骨肉瘤MG63裸小鼠动物模型，以Ad-VEGFsiRNA瘤组织注射治疗，检测移植瘤组织中VEGF的表达情况及Ad-VEGFsiRNA对肿瘤生长和肺转移的抑制作用。结果：成功构建了表达VEGFsiRNA的重组腺病毒载体AdVEGFsiRNA；体外与体内实验检测Ad-VEGFsiRNA转染骨肉瘤细胞MG63后显著抑制VEGF表达。荷人骨肉瘤裸鼠经Ad-VEGFsiRNA治疗后，显示其对移植骨肉瘤生长有明显抑制作用（P<0.05），并且对骨肉瘤的肺转移有显著的抑制作用（P<0.05）。结论：所构建的Ad-VEGFsiRNA可以有效抑制骨肉瘤中VEGF表达，使裸鼠移植骨肉瘤生长减慢，并且显著抑制荷瘤裸小鼠肺转移的发生。     

腺病毒介导人VEGF-siRNA对裸鼠移植骨肉瘤的抑制作用

目的:研究腺病毒介导人VEGF-siRNA对裸鼠移植骨肉瘤的治疗作用.方法:利用腺病毒重组技术将VEGF-siRNA基因克隆入增殖缺陷型腺病毒基因组中,构建重组腺病毒Ad-VEGF-siRNA,重组腺病毒体外感染骨肉瘤MG63细胞,RT-PCR检测MG63细胞VEGF的表达水平.建立荷人骨肉瘤MG63裸小鼠动物模型,以Ad-VEGF-siRNA瘤组织注射治疗,检测移植瘤组织中VEGF的表达情况及Ad-VEGF-siRNA对肿瘤生长和肺转移的抑制作用.结果:成功构建了表达VEGF-siRNA的重组腺病毒载体Ad-VEGF-siRNA;体外与体内实验检测Ad-VEGF-siRNA转染骨肉瘤细胞MG63后显著抑制VEGF表达.荷人骨肉瘤裸鼠经Ad-VEGF-siRNA治疗后,显示其对移植骨肉瘤生长有明显抑制作用(P<0.05),并且对骨肉瘤的肺转移有显著的抑制作用(P<0.05).结论:所构建的Ad-VEGF-siRNA可以有效抑制骨肉瘤中VEGF表达,使裸鼠移植骨肉瘤生长减慢,并且显著抑制荷瘤裸小鼠肺转移的发生.     

Increased Fas expression reduces the metastatic potential of human osteosarcoma cells.

PURPOSE: The process of metastasis requires the single tumor cell that seeds the metastatic clone to complete a complex series of steps. Identifying factors responsible for these steps is essential in developing and improving targeted therapy for metastasis. Resistance to receptor-mediated cell death, such as the Fas/Fas ligand pathway, is one mechanism commonly exploited by metastatic cell populations. EXPERIMENTAL DESIGN AND RESULTS: LM7, a subline of the SAOS human osteosarcoma cell line with low Fas expression, was selected for its high metastatic potential in an experimental nude mouse model. When transfected with the full-length Fas gene (LM7-Fas), these cells expressed higher levels of Fas than the parental LM7 cells or LM7-neo control-transfected cells. These cells were also more sensitive to Fas-induced cell death than controls. When injected intravenously into nude mice, the LM7-Fas cell line produced a significantly lower incidence of tumor nodules than control cell lines. Lung weight and tumor nodule size were also decreased in those mice injected with LM7-Fas. Levels of Fas were quantified in osteosarcoma lung nodules from 17 patients. Eight samples were Fas negative, whereas the remaining 9 were only weakly positive compared with normal human liver (positive control). CONCLUSIONS: Our results demonstrate that altering Fas expression can impact the metastatic potential of osteosarcoma cells. We conclude that the increase of Fas on the surface of the LM7 osteosarcoma cells increased their sensitivity to Fas-induced cell death in the microenvironment of the lung, where Fas ligand is constitutively expressed. Thus, loss of Fas expression is one mechanism by which osteosarcoma cells may evade host resistance mechanisms in the lung, increasing metastatic potential. Fas may therefore be a new therapeutic target for osteosarcoma.     

ELAM-1在鼻咽癌裸鼠移植瘤中的表达及其与转移的关系

目的 建立裸鼠鼻咽癌转移模型并探讨 E-选择素（ELAM-1）与鼻咽癌转移的相关性。方法 将鼻咽癌5-8F细胞悬液注射于裸鼠左后肢爪垫，观察裸鼠状态、成瘤情况并测量裸鼠体重及移植瘤长短径；采用连续病理切片苏木精-伊红染色观察移植瘤及转移情况，将16只人鼻咽癌荷瘤裸鼠分为转移组和非转移组；采用免疫组织化学法检测两组移植瘤组织中ELAM-1的表达。 结果 16只裸鼠均成瘤，成瘤率为100.0%，其中10只裸鼠出现转移瘤，转移率为62.5%。建模前，两组裸鼠体重差异无统计学意义［（13.83±0.56）g vs （14.62±0.30） g，t=1.026，P=0.071］。建模后4~7周，裸鼠瘤体体积呈指数增长，且转移组移植瘤增长速度较非转移组快，非转移组裸鼠瘤体体积小于转移组［（198.91 ± 163.29） mm³ vs （268.76 ±174.31） mm³，t=4.376，P=0.005］。ELAM-1在鼻咽癌裸鼠移植瘤、淋巴结转移灶及远处转移灶中的表达均为阳性，主要表达于细胞膜。转移组移植瘤光密度值高于非转移组（0.4497±0.0705 vs 0.0435±0.0082，t=4.388，P＝0.001）。结论 本研究成功构建稳定性好、转移率高的鼻咽癌裸鼠移植瘤转移模型，且ELAM-1在裸鼠移植瘤中高表达，可促进鼻咽癌裸鼠移植瘤生长和转移。     

Mycophenolic acid is a drug with the potential to be repurposed for suppressing tumor growth and metastasis in osteosarcoma treatment

Our previous review of proteomics data showed that in osteosarcoma, some overexpressed proteins were targets of FDA-approved immunosuppressive and anti-arrhythmic drugs, including mycophenolate mofetil (MMF), ribavirin, leflunomide, azathioprine and digoxin. Here, these drugs were screened for growth inhibitory effects in human osteosarcoma cell lines, including MNNG/HOS, U2OS, SaOS-2, MG-63 and 143B cells. Only mycophenolic acid (MPA), an active metabolite of MMF, efficiently inhibited osteosarcoma cell growth with IC₅₀ values of 0.46-7.3 μM; these values are in the therapeutic range for organ transplant patients. At a therapeutic dose (10 μM), MPA significantly inhibited colony formation, caused cell cycle arrest in the S phase, and induced apoptosis. Moreover, the in vitro invasion of osteosarcoma cells was reduced by MPA by inhibiting cell migration capability. The in vivo antitumor effect of MMF was determined in nude mice harboring 143B cell xenografts. Daily oral administration of 200 mg/kg/day MMF for 2 weeks significantly suppressed tumor growth in treated mice, achieving 57.4 ± 11.1% tumor growth inhibition. Compared with the vehicle group, the MMF group treated with 50–200 mg/kg/day for 3 weeks had a significant reduction in the number of lung metastatic nodules in a tail vein-lung metastasis model of 143B cells. MMF doses of 50, 100 and 200 mg/kg/day are approximately equivalent to the non-toxic doses of 0.25, 0.5 and 1 g/day in humans, respectively. These findings indicate that MPA/MMF can effectively control osteosarcoma tumor growth and metastasis. Thus, the potential to repurpose MPA/MMF for use in osteosarcoma chemotherapy is of great interest.     

Imaging the inhibition by anti-β1 integrin antibody of lung seeding of single osteosarcoma cells in live mice

Integrins play a role in tumor growth and metastasis. However, the effect of integrin inhibition has not been visualized on single cancer cells in vivo. In this study, we used a powerful subcellular in vivo imaging model to demonstrate how an anti-integrin antibody affects seeding and growth of osteosarcoma cells on the lung. The 143B human osteosarcoma cell line, expressing red fluorescent protein (RFP) in the cytoplasm and green fluorescent protein (GFP) in the nucleus, was established. Such double-labeled cells enable imaging of apoptosis and mitosis and other nuclear-cytoplasmic dynamics. Using the double-labeled osteosarcoma cells, single cancer-cell seeding in the lung after i.v. injection of osteosarcoma cells was imaged. The anti-β1 integrin monoclonal antibody, AIIB2, greatly inhibited the seeding of cancer cells on the lung (experimental metastasis) while a control antibody had no effect. To image the efficacy of the anti-integrin antibody on spontaneous metastasis, mice with orthotopically-growing 143B-RFP cells in the tibia were also treated with AIIB2 or control anti-rat IgG1 antibody. After 3 weeks treatment, mice were sacrificed and primary tumors and lung metastases were evaluated with fluorescence imaging. AIIB2 significantly inhibited spontaneous lung metastasis but not primary tumor growth, possibly due to inhibition of lung seeding of the cancer cells as imaged in the experimental metastasis study. AIIB2 treatment also increased survival of mice with orthotopically growing 143B-RFP.     

Expression of metastatic potential of tumor cells in young nude mice is correlated with low levels of natural killer cell-mediated cytotoxicity

Of 6- and 3-week-old nude mice given intravenous injections of murine tumor cells with well-defined metastatic properties, only the 3-week-old mice developed lung tumor colonies in significant numbers. The quantitative differences in metastatic potential among tumor cell lines injected into syngeneic recipients were also maintained following intravenous injection into young nude mice. Successful metastasis in 3-week-old nude mice is correlated with the low levels of natural killer cell activity detected in these young recipients. Boosting of the natural killer cell activity of 3-week-old nude mice by the administration of bacterial adjuvants and interferon inducers significantly inhibited metastasis formation. The differences in metastasis development could not be attributed to differences in the initial arrest of tumor cells in the pulmonary vascular bed, but rather to a better survival of the arrested cells in the lungs of 3-week-old nude mice as compared with 6-week-old counterparts. We conclude that low levels of NK cell activity are associated with increased incidence of experimental metastasis.     

抑制整合素α9基因的表达对黑色素瘤细胞B16F1的生长和肺转移的影响

目的 观察shRNA干扰整合素α9（ITGA9）的表达对黑色素瘤细胞B16F1的生长和肺转移的影响。方法 用RNA干扰技术下调B16F1中ITGA9的表达,建立小鼠皮下成瘤和肺转移模型,观察肿瘤生长情况,计数肺转移灶数量。结果 ITGA9-shRNA转染组的肿瘤生长速度减慢（P＜0.05）,实验终点,该组肿瘤平均体积与scramble-shRNA组相比下降36%;肺转移灶数量显著减少（P＜0.05）。结论 下调ITGA9的表达可抑制黑色素瘤细胞B16F1在小鼠体内的生长和肺转移。ITGA9可能成为黑色素瘤的治疗靶点。     

肺癌脑转移细胞的筛选及实验动物模型的建立

目的：通过反复裸鼠体内肺癌细胞接种,筛选出特异性脑转移肺癌细胞株,并建立可稳定产生脑转移的肺癌实验动物模型.方法：应用人肺癌细胞株PC-14尾静脉注射接种裸鼠,5周后处死裸鼠,取出脑转移肿瘤组织,行原代培养后再次接种裸鼠,反复几个循环,观察脑转移形成情况.结果：经过4个循环后,筛选出的PC-14/B肺癌细胞尾静脉接种可在裸鼠产生特异脑转移,可应用于建立稳定转移的肺癌脑转移实验动物模型.结论：应用肺癌细胞株行反复裸鼠体内接种,是建立肺癌脑转移实验动物模型的可行方法.     

抑制肿瘤细胞骨保护素表达对乳腺癌细胞致骨转移能力的影响

目的观察抑制肿瘤细胞骨保护素（0steoprotegerin,OPG）表达对乳腺癌MDA～MB-231细胞株致骨转移的影响。方法32只4～6周龄雌性裸鼠被随机分为A、B、C、D4组,每组8只,A、C组的每只裸鼠按分组分别以5×10。个MDA—MB-231细胞注射入左心室（A组）或左胫骨骨髓腔（C组）。B、D组的每只裸鼠按分组分别以5×10。个MDA—MB-231i细胞（OPG表达抑制）注射人左心室（B组）或左胫骨骨髓腔（D组）,42d后行病理检查,比较A、B组骨转移发生率和骨转移灶数量,以及C、D组的骨肿瘤体积。定量资料的比较采用t检验或秩和检验,定性资料比较采用Fisher确切概率检验。结果A组有6只发生骨转移,全组共检出不连续性骨转移灶23处;B组有3只发生骨转移,全组共检出不连续性骨转移灶8处。A组的骨转移发生率和转移灶数量虽高于B组,但两者差异并无统计学意义（P〉0．05）。C组肿瘤平均体积为（66．29±41．01）mm3,D组肿瘤平均体积为（23．70±16．14）mm3,C组骨肿瘤体积大于D组,两组间差异有统计学意义（P=0．02）。结论乳腺癌细胞致骨转移能力与其OPG表达水平密切相关,抑制OPG表达可以降低乳腺癌细胞致骨转移的能力。