5-Aza-CdR对人结肠癌裸鼠移植瘤抑制作用及其机制的研究

目的 观察DNA甲基化转移酶抑制剂5氮杂-2'-脱氧胞苷(5-Aza CdR)对人结肠癌裸鼠移植瘤生长的抑制作用,探讨其与移植瘤细胞RUNX3基因表达和甲基化的相关性.方法 皮下接种SW480细胞建立人结肠癌裸鼠移植瘤模型.应用随机数字表法分为3组,A组为对照组,腹腔注射磷酸盐缓冲液(2 μg/g);B组为低剂量实验组,腹腔注射5-Aza-CdR(1 μg/g);C组为高剂量实验组,腹腔注射5-Aza-CdR(2 μg/g).各组每周给药3次,连续给药4周,末次给药后处死裸鼠.观察各组移植瘤生长情况及病理形态学改变,并采用TUNEL法检测移植瘤细胞凋亡情况,MSP法检测RUNX3基因的甲基化状态,Real time RT-PCR及免疫组化检测RUNX3的表达水平,分析组间统计学差异.结果 给药4周后,A组移植瘤体积为(3.63±1.00) cm3,B组(3.02±1.43) cm3,C组(1.80±0.80) cm3,C组与A、B组比较,差异有统计学意义,F=7.061,P=0.003.TUNEL法检测结果显示,C组移植瘤凋亡指数较高,为(5.66±0.70)％,与A组(1.14±0.45)％、B组(2.83±0.69)％比较,差异有统计学意义,F=53.631,P＜0.001.基因甲基化检测发现,A组有较高的RUNX3基因甲基化水平,而B组及C组的RUNX3基因的非甲基化务带明显扩增;而且在RUNX3基因表达上,A组mRNA相对表达量为14.84±0.53,明显低于B组的21.66±0.45、C组的46.72±2.64,差异有统计学意义,F=910.128,P＜0.001;A组RUNX3蛋白阳性表达率为(6.84±2.21)％,亦明显低于B组(14.54±3.98)％及C组(16.25±2.71)％,差异有统计学意义,F=10.745,P=0.004.结论 5-Aza-CdR可有效抑制人结肠癌裸鼠移植瘤的生长,诱导移植瘤细胞凋亡,其机制与逆转RUNX3基因的过甲基化状态,诱导移植瘤细胞RUNX3基因的重新表达相关.     

Human ovarian cancer xenografts in nude mice: characterization and analysis of antigen expression

We have characterized 13 different human ovarian cancer xenografts grown subcutaneously in nude mice. The tumor lines represented 5 histological subtypes: serous (4), mucinous (4), clear-cell carcinoma (1), carcinosarcoma (1) and undifferentiated (3). The specific histology and the degree of differentiation resembled those of the original patients' tumors and were maintained upon serial transfer. Volume doubling times of the xenografts ranged from 3.5 to 15 days. The xenografts were also analyzed for their antigen expression using 20 monoclonal antibodies (MAbs) reactive with 15 tumor-associated antigens. Immunohistochemical examination of tissue sections showed a positive reaction pattern with MAbs 115D8, 140C1, 139H2, 175C5, HMFG1 and HMFG2, each recognizing episialin, as well as with MAbs AUA1, 358.4.32 and 199-157 in xenografts of the serous, mucinous and clear-cell carcinoma subtype. MAb OC125 was reactive with xenografts of the serous subtypes. Other antibodies, such as 494 and OV-TL3 infrequently demonstrated positive reactions. Reactivity of all MAbs was low in the carcinosarcoma and undifferentiated tumor lines. With the exception of AUA1, 495 and 126E5, all MAbs revealed a heterogeneous staining pattern. MAbs against episialin and OC125 predominantly stained the apical site of the tumor cells. Strongest reactivity with almost all histological subtypes was observed with MAbs 115D8, 140C1, 139H2 and AUA1. In cases where we were able to compare the patients' tumor tissue with the respective xenografts, retention of antigen expression was demonstrated in each instance. Release of tumor-associated antigens was shown for CA125 in 2 serous-tumor lines, for CA15.3 in 1 serous-tumor line, and for CEA in 3 lines of the mucinous subtype. This panel of human tumor xenografts could be a valuable tool to determine the potential usefulness of MAb-guided therapy in ovarian cancer.     

Contrasting actions of estradiol on the growth of human gastric cancer xenografts in nude mice

The effects of estradiol on the growth of six human gastric xenografts in nude mice were studied and diverse effects were found, including one case of stimulation, two of inhibition and three of unchanged condition. Neither the histological features of the original tumor nor the estrogen-binding capacity seemed to be related to the response to estradiol. It is concluded that the growth of human gastric cancer can be modulated by estradiol.     

Suramin inhibits growth of human osteosarcoma xenografts in nude mice

The effect of suramin on tumor growth and morphology in two different human osteosarcoma xenografts (L-I OSM and L-II OSM) grown in BALB/cA-nu/nu mice was studied. Suramin (total dose, 720 mg/kg) given by i.p. injection (60 mg/kg/dose) for up to 9 weeks significantly inhibited osteosarcoma cell growth in both tumors, suramin-treated tumors showing only one-third or less of the volume of nontreated controls. Cell cycle distribution of tumor cells measured by DNA flow cytometry demonstrated that suramin treated caused accumulation of cells in the S and G2 phases of the cell cycle, in both L-I OSM and L-II OSM. In the aneuploid L-II OSM tumor suramin preferentially inhibited the growth of aneuploid cells, leading to a decrease in the ratio of aneuploid to diploid cells. Both osteosarcomas retained their histological appearance and the liver, spleen, heart, and kidneys of the treated animals were unaffected by suramin. These results are compatible with the view that suramin inhibits the growth of human osteosarcomas by cytostatic effects.     

siRNA介导的间皮素基因沉默对卵巢癌裸鼠腹腔移植瘤生长的影响

目的:研究间皮素(mesothelin, MSLN)基因被沉默后的卵巢癌细胞SKOV3-MSLN-shRNA增殖能力的变化,以及MSLN基因沉默对裸鼠卵巢癌腹腔移植瘤生长的影响.方法:利用针对MSLN基因的siRNA慢病毒液和对照组慢病毒液分别感染SKOV3细胞,建立SKOV3-MSLN-shRNA细胞和SKOV3-MSLN-neg细胞的稳定转染株;以SKOV3细胞作空白对照,用平板克隆形成法和细胞计数法检测3组细胞的增殖能力.应用3组细胞分别建立裸鼠卵巢癌腹腔移植瘤模型,2周后处死裸鼠,观察每组动物的成瘤率及每只裸鼠的肿瘤质量、肿瘤数目和肿瘤种植部位等.结果:SKOV3-MSLN-shRNA细胞的体外增殖能力明显低于SKOV3-MSLN-neg细胞和SKOV3细胞,差异有统计学意义(P<0.05).SKOV3-MSLN-shRNA组裸鼠成瘤率为60%,而2个对照组SKOV3-MSLN-neg和SKOV3细胞的裸鼠成瘤率均为100%,差异无统计学意义(P＞0.05).SKOV3-MSLN-shRNA组动物的肿瘤数目、肿瘤质量及肿瘤种植部位明显低于2个对照组 (P<0.05).结论:MSLN基因沉默可以降低卵巢癌SKOV3细胞的体外增殖能力,同时可以抑制卵巢癌裸鼠腹腔移植瘤的生长和种植.     

Intraperitoneal xenografts of human epithelial ovarian cancer in nude mice

Using continuous human ovarian cancer cell lines, i.p. xenografts were successfully established in nude mice from four of four attempts. When primary tumor material was used, xenografts grew in 8 of 10 attempts. From these eight, three passageable xenograft cell lines have been established. To our knowledge, this is the first report published of such xenografts. I.p. xenografts closely mimic the clinical behavior of human ovarian cancer, and those developed from primary tumor material maintain close morphological similarity to the parent primary tumor. When expression of placental alkaline phosphatase and the tumor associated antigens defined by the monoclonal antibodies HMFG1, HMFG2, AUA1, and F36/22 by these models was determined, those i.p. xenografts derived from primary tumor material exactly matched the original tumor, while none of the xenografts derived from the cell lines expressed these antigens. These models will be useful for investigating the biology and treatment of ovarian cancer.     

Chemosensitivity of human gastrointestinal and breast cancer xenografts in nude mice

Experimental chemotherapies for 15 human cancers xenografted into nude mice were performed using 14 anticancer agents including 6 drugs in clinical use. Treatment with each single agent was performed for every cancer line using the maximum tolerated dose through continuous daily (antimetabolites) or intermittent (cytocidal agents) schedules. Effectiveness of each drug was evaluated by inhibition rate (IR) calculated from mean tumor weights of both treated and untreated groups. Response to a treatment was judged as effective when the IR was higher than 58%. Response rate of each drug was as follows; MMC was 67%, UFT 67%, CPA 47%, FT-207 40%, ACNU 33%, ADR 27%, SOAz 87%, 5'-DFUR 80%, MXT 20%, Leakadine 17%, M-83 17%, CAM 0% and GANU 0%. Generally, the experimental results for each drug on the xenografts was in good accordance with the known clinical effect of each drug on the same type of cancer. On the other hand, individual cancer xenografts showed considerable differences in chemosensitivity. Some tumors were sensitive to a majority of the drugs, whereas some were resistant to many of them. Each cancer line seemed to retain individuality in its spectrum of chemosensitivity irrespective of whether it originated from the same organ or whether it was of similar histologic type. This fact suggests the necessity of selecting drugs effective to the individual tumor when considering a patients chemotherapy regime.     

红景天对裸鼠乳腺癌移植瘤的影响

背景与目的：体内外的肿瘤研究显示红景天具有一定的抗肿瘤作用，本文探讨红景天对于乳腺癌移植瘤的生长的抑制作用及其可能的机制。方法：以人乳腺癌MDA—MB-435细胞的裸鼠移植瘤模型作为研究对象，采用免疫组织化学方法，从转移瘤内的肿瘤细胞增殖活性方面，探讨红景天对乳腺癌移植瘤的作用。结果：与生理盐水对照组相比，红景天治疗组的移植瘤体积有所缩小，但未达到统计学意义（99．95mm^3比174．60mm^3，P=0．535）；红景天治疗后移植瘤内乳腺癌细胞增殖指标Ki-67染色比例、染色强度降低，其综合评价指数H-分数均值明显降低（152．8比86，P=0．014）；移植瘤内增殖指标PCNA的染色强度和比例的综合评价指数H-分数均值有所降低，但未达到统计学意义（242比210，P=0．221）。结论：红景天的体内抗癌机制可能部分通过抑制肿瘤的增殖活性而实现。     

Celastrol inhibits the growth of human glioma xenografts in nude mice through suppressing VEGFR expression

Celastrol, a compound purified from Tripterygium wilfordii whose preparations have been used for clinical treatment for rheumatoid arthritis, has been demonstrated to have antiangiogenic activity, and be inhibitory against mice tumor growth by a few recent studies. However, whether its antiangiogenic activity plays a role in the celastrol-mediated suppression of tumor growth and the molecular basis of anti-tumor activity are poorly understood. In this study, we found that celastrol inhibited the growth of human glioma xenografts in mice, which concurred with the suppression of angiogenesis. Interestingly, while celastrol had no effect on either the expression of VEGF or its mRNA levels, celastrol treatment lowered the expression levels of its receptors (VEGFR-1 and VEGFR-2) and their mRNA levels. These findings suggest that celastrol have potential to be used as an antiangiogenesis drug through its role in suppressing VEGF receptors expression that might consequently reduce the signal transduction between VEGF and VEGFR.     

Immunohistochemical demonstration of epidermal growth factor in human gastric cancer xenografts of nude mice.

Thirty-two surgical specimens and three cell lines of human gastric cancers were used for subcutaneous transplantation into nude mice, resulting in the establishment of eight (25%) xenografts from the surgical specimens and two (67%) from the cell lines. The localization of epidermal growth factor (EGF) in the surgical specimens and cell lines of the gastric cancers and their xenografts in nude mice was then investigated immunohistochemically. Epidermal growth factor was stained in the cytoplasm of the cancer cells, being detected in 16 (50%) of the 32 surgical specimens and in all of the cell lines. Seven (44%) of the sixteen EGF-positive surgical specimens and one (6%) of the 16 EGF-negative ones were tumorigenic in nude mice. All of the xenografts in nude mice were positive for EGF. The tumorigenicity of human gastric cancer xenografts in nude mice may, therefore, be correlated with the presence of EGF in cancer cells.     

塞来昔布抑制人类三阴性乳腺癌裸鼠移植瘤生长的实验研究

 【摘要】　目的　探讨塞来昔布（celecoxib）对人类三阴性乳腺癌（TNBC）肿瘤生长及细胞凋亡的影响。方法　32只裸鼠于背部皮下接种人类TNBC细胞株MDA-MB-231,随机分为空白对照组及低、中、高剂量塞来昔布组（25、50、100 mg?kg-1?d-1）。实验结束后,留取移植瘤标本,观察用药前后裸鼠肿瘤体积的变化;流式细胞术（FCM）检测肿瘤细胞凋亡率;免疫组织化学法检测NF-κB p65和p50分子的表达;Western blot法检测凋亡相关分子Caspase-3、Survivin蛋白的表达。结果　塞来昔布治疗组肿瘤体积较对照组均明显减小。中、高剂量塞来昔布治疗组凋亡率分别为（13.58±3.16）％、（21.91±4.75）％,与对照组的（3.15±1.73）％相比差异有统计学意义（t＝6.736,12.151,均P＜0.05）,塞来昔布低、中、高剂量组p65表达阳性率分别为79.3 %、46.7 %、23.9 %,与对照组（89.7 %）相比差异有统计学意义（χ2＝3.312,10.785,15.900,均P＜0.05）。Western blot结果显示,塞来昔布治疗后肿瘤组织中Caspase-3蛋白出现了裂解片段,并且随药物浓度增加,裂解片段表达量逐渐增加。Survivin蛋白随药物浓度增加表达逐渐下调。结论　塞来昔布可以诱导TNBC裸鼠移植瘤细胞凋亡,抑制肿瘤生长,其抗肿瘤作用机制可能部分与抑制p65分子以及下调Survivin蛋白表达有关。     

Inhibitory effect of pingyangmycin on human liver cancer and stomach cancer xenografts in nude mice

Established human cancer cell lines derived from liver cancer (BEL-7402), nasopharyngeal cancer (CNE-2) and stomach cancer (MGC-803) were used in this study. These human cancer cells have been serially transplanted in nude mice. As determined by clonogenic assay, pingyangmycin (bleomycin A5) was highly cytotoxic to these three cell lines, of which the liver cancer cell line was more sensitive than the other two. At a tolerated dose level, pingyangmycin exhibited a remarkable growth inhibition on the growth of the liver cancer and stomach cancer xenografts, the inhibition rates being 70% and 85%, respectively. No pathologic changes were found in the organs of treated animals.     

Synthesis of glycosaminoglycans by undifferentiated and differentiated HT29 human colonic cancer cells

Among the extracellular matrix components which have been suggested to be involved in developmental and neoplastic changes are glycosaminoglycans (GAGs). To try to correlate their amount and nature with the process of enterocytic differentiation, we studied glycosaminoglycan synthesis of human colonic adenocarcinoma cells (HT29 cell line) by [3H]glucosamine and [35S]sulfate incorporation. Enterocytic differentiation of the cells obtained in a sugar-free medium (for review, see A. Zweibaum et al. In: Handbook of Physiology. Intestinal Transport of the Gastrointestinal System, in press, 1987) resulted in a marked increase in total incorporation of labeled precursors (20-fold for [3H]glucosamine, 4.5-fold for [35S]sulfate) as well as in uronic acid content (5-fold); most of the synthesized GAGs were found associated with the cell pellet. Chromatographic and electrophoretic analysis of the labeled GAGs revealed that undifferentiated cells synthesized and secreted hyaluronic acid, heparan sulfate, and one class of chondroitin sulfate. Differentiation of HT29 cells because associated with the synthesis of an additional class of chondroitin sulfate (CS4) concomitant to a decrease in heparan sulfate which is no longer found secreted in the medium. Furthermore, the charge density of this latter GAG component varied as assessed by a shift of its affinity on ion-exchange chromatography.     

Survivin基因沉默抑制结肠癌生长的动物实验研究

目的 探究survivin基因沉默对人结肠癌Lovo细胞裸鼠移植瘤生长的抑制作用.方法 构建靶向survivin的shRNA载体SUR和阴性对照质粒Neg,并将其转染人结肠癌Lovo细胞,分别种植到裸鼠皮下建立人结肠癌裸鼠移植瘤模型.随后观察各组裸鼠移植瘤生长情况,免疫组化方法检测移植瘤survivin蛋白的表达,TUNEL法检测肿瘤细胞的凋亡情况.结果 移植转染细胞8周,与空白对照组比较,SUR组移植瘤的体积和质量均有显著缩小(P<0.05),体积和质量抑瘤率分别为48.9%和51.2%.与空白对照组比较,SUR组移植瘤survivin表达显著下调,表达指数为31.9%;SUR组肿瘤细胞凋亡显著增加,凋亡指数18.47%(P<0.05).阴性对照Neg组的上述指标与空白对照组比较,差异均无统计学意义.结论 Survivin基因沉默能够抑制人结肠癌Lovo细胞裸鼠移植瘤的生长.     

Imaging and biodistribution of 111In-labeled anti-carcinoembryonic antigen monoclonal antibodies in nude mice bearing human colon cancer xenografts

Anti-CEA monoclonal antibody was labeled with 111In using DTPA cyclic anhydride. The radiochemical purity of the product was more than 99% and specific binding was 38%. Imaging and biodistribution of this radiopharmaceutical in nude mice bearing human colon cancer xenografts were investigated. The results showed that a clear image of tumor was obtained by gamma camera between 24 to 120 hrs, best in 72 hrs, after injection. A high uptake of 111In-labeled monoclonal antibodies in tumor tissue was also observed, although the radioactivity in liver was considerable.     

Effects of cidofovir on human papillomavirus-positive cervical cancer cells xenografts in nude mice

Cidofovir (CDV) is an acyclic nucleoside phosphonate analog that shows broad spectrum anti-DNA virus activity. In this study, we have investigated the influence of cidofovir on the tumor xenografts derived from HeLa and SiHa cells on nude mice. The HeLa/SiHa xenografts in nude mice were established by inoculating cells subcutaneously. Administration of cidofovir by intratumoral injection led to significant tumor reduction. Enhanced protein levels of p53 and p-pRb within the tumor samples were observed. Immunohistology analysis of the tumor sections indicated decreased PCNA index and increased apoptosis index. Our study gives more evidence and explanation on in vivo inhibition effect of cidofovir on HPV genome-positive cervical carcinoma cell line xenografts.     

Lewisy抗原对人卵巢癌细胞RMG—I裸鼠移植瘤P—Akt蛋白表达的影响

目的：探讨α1,2-岩藻糖转移酶基因转染对人卵巢癌细胞株RMG—I裸鼠移植瘤中磷酸化Akt（P—Akt）蛋白表达的影响。方法：利用已经建立的Lewis y抗原稳定高表达的卵巢癌细胞株RMG—I—H建立裸鼠移植瘤模型,利用免疫组织化学染色法检测基因转染前后裸鼠移植瘤组织中LewisY抗原及P—Akt蛋白的表达。结果：基因转染后的裸鼠移植瘤组织细胞表面LewisY抗原及P—Akt蛋白的表达均明显增加,转染组与非转染组之间差异有统计学意义（P〈0．05）。结论：Lewis y抗原明显促进卵巢癌细胞株RMG—I裸鼠移植瘤P—Akt蛋白的表达。     

沉默HMGB1 基因对裸鼠人上皮性卵巢癌移植瘤生长的抑制作用

目的：探讨高迁移率族蛋白B1（high mobility group box 1,HMGB1）基因对裸鼠人上皮性卵巢癌移植瘤生长的影响。方法：选取对数生长期的人上皮性卵巢癌细胞株SKOV3 细胞建立裸鼠人上皮性卵巢癌移植瘤模型,将造模成功的裸鼠随机分成对照组和HMGB1-siRNA 组,分别在接种细胞后第7、9、11、14、16 天于荷瘤鼠腋下注射等量的生理盐水和HMGB1-siRNA。3 周后颈椎脱臼法处死裸鼠、分离肿瘤组织,测量肿瘤的体积并绘制肿瘤生长曲线,以Tunel 染色法检测移植瘤细胞的凋亡情况,Western blotting 检测移植瘤组织中HMGB1、STAT3、p-STAT3 的表达水平,免疫组化染色技术检测移植瘤组织中VEGF-A的表达和微血管形成情况。结果：与对照组相比,HMGB1-siRNA组的肿瘤体积增长速度减缓,第21 天起HMGB1-siRNA组的肿瘤体积显著小于对照组（P<0.05）;HMGB1-siRNA 成功敲降了移植瘤组织细胞中HMGB1 mRNA的表达,移植瘤组织中HMGB1-siRNA组的细胞凋亡率较对照组显著升高[ （34±8）% vs（6±2）%,P=0.04],HMGB1 和p-STAT3 表达显著降低（P<0.05）,VEGF-A表达和微血管数均显著低于对照组（均P<0.05）。结论：敲降HMGB1 基因可能通过抑制HMGB1/STAT3 信号通路降低VEGF-A的表达和微血管形成,从而促进肿瘤组织细胞凋亡和减缓移植瘤生长。     

Metastases of human tumor xenografts in nude mice

In the present study, using systematic microscopic examination, we tried to determine the true incidence of metastases in nude mice bearing a wide variety of human tumors. A total of 63 malignant tumors were successfully transplanted subcutaneously and 831 nude mice bearing tumors were examined. It appeared that 17 of the 63 tumors (26.9%) retained their metastatic ability in nude mice. Most of these tumors were adenocarcinomas (11/17 cases). Generally the metastatic deposits in the lungs and, to a lesser extent, in the lymph nodes were small and thus only detectable on microscopic examination. We also found a positive correlation between the presence of metastases and neoplastic infiltration of the lymphatic and/or blood vessels around the subcutaneous tumors. Metastatic human tumors, including neoplastic cells from effusion, exhibited higher metastatic ability than primary tumors (p less than 0.005). However, the expression of this metastatic potential depends on several factors including tumor volume, survival time after inoculation and murine hepatitis infection. Thus, animals with metastases bore larger tumors (9.56 cm3) than those without metastasis (6.35 cm3; p less than 0.0001). Moreover, survival time after inoculation was longer in mice with metastases (104 days) than in mice without metastases (81 days; p less than 0.0001). A negative influence of viral hepatitis on the incidence of metastases was observed. This may simply be related to the shortened life span of the animals. Death due to this infection may precede the expression of the metastatic potential.     

缺氧对乳腺癌和宫颈癌裸鼠移植瘤EGFR表达及细胞凋亡的影响

目的 在乳腺癌、宫颈癌裸鼠成瘤模型中观察缺氧对表皮生长因子受体(EGFR)表达和细胞凋亡的影响。方法 以人乳腺癌MCF-7和宫颈癌HeLa移植裸鼠模型为研究对象,利用激光共聚焦显微镜观察缺氧区程度和EGFR表达情况;利用TUNEL染色观察EGFR表达对缺氧肿瘤细胞凋亡的影响。结果 在乳腺癌MCF-7和宫颈癌HeLa细胞缺氧程度高的区域,EGFR高表达和低表达均存在。此外,与EGFR的低表达肿瘤组织相比,凋亡程度在EGFR高表达肿瘤组织中降低。结论 乳腺癌、宫颈癌细胞缺氧对EGFR表达呈非均一性作用,缺氧诱导EGFR表达与细胞凋亡呈负相关。