Oral Administration of Uracil-Tegafur (UFT) Inhibits Liver Micrometastasis of Human Colon Cancer in an Orthotopic Nude Mouse Model and Its Early Detection System

Purpose To evaluate the effect of UFT (an oral antineoplastic drug combining uracil and tegafur) as an adjuvant chemotherapy.Methods We examined whether UFT inhibits micrometastasis of the liver from colon cancer implanted into the cecum of nude mice in an orthotopic model. Moreover, we studied whether our early detection system using a polymerase chain reaction (PCR) of the human -globin gene would be useful in this model.Results The administration of 20mg/kg UFT p.o., which is a relatively small dose compared with 65mg/kg of the maximum tolerated dose of this drug in mice, inhibited liver metastasis completely when started immediately after a cecectomy (micrometastasis present at this time), but did not inhibit liver metastasis significantly when started at 4 weeks after a cecectomy (gross tumor present at this time). There were no severe toxicities at this dose. In our PCR study, all livers in 10 mice to which therapy was given immediately after a cecectomy and without liver metastasis showed no PCR-amplified fragment, while 7 of 10 livers in the nontreatment group in which gross liver metastases were not observed demonstrated this fragment.Conclusions These findings indicate that UFT is useful for either adjuvant chemotherapy or the inhibition of micrometastasis, and our system to detect micrometastasis by examining the human -globin gene is useful for the early evaluation of the efficacy of these drugs.     

Radioimmunoscintigraphy using an anti-prostate monoclonal antibody (E4): a dosimetric evaluation

The aim of this study was to evaluate different strategies to increase the tumour radiation dose for experimental radioimmunotherapy using ¹²⁵I-labelled monoclonal antibody (MAb) E4 in a nude mice model xenografted with DU-145 tumours. The effects from a single injection of the ¹²⁵I-labelled MAb E4, the same total amount of radiolabelled MAb E4 divided into three repeated injections, and the effect of pre-targeting with non-labelled MAb E4 for reducing the amount of shed antigen were investigated. Based on repetitive quantitative radioimmunoscintigraphies, calculation of the tumour radiation dose delivered from the ¹²⁵I-nuclide was performed for each strategy. The single injection strategy without pretargeting rendered the highest mean tumour radiation dose, i.e. 0.23 Gy/MBq. Pretargeting with non-labelled MAb E4 before a single injection of [¹²⁵I]E4 resulted in a slightly lower mean tumour radiation dose, i.e. 0.19 Gy/MBq, compared to the single injection alone. An even lower mean tumour radiation dose, i.e. 0.14 Gy/MBq, was obtained when the same total administered amount of activity was divided into three separate injections given in 10-day intervals. We concluded that the single injection strategy is the most efficient when using MAb E4 in this tumour model. The tumour radiation doses were not increased by dividing the same amount of activity into three injections or by pretargeting with non-labelled MAb E4. Received: 30 October 2000 / Accepted: 23 February 2001     

人血管瘤裸小鼠移植模型形态学动态观察

目的建立人血管瘤裸小鼠异种移植模型并动态观察移植物形态学变化。方法将人婴幼儿血管瘤组织切分为96个小块移植于16只裸小鼠皮下，定期测量瘤体体积，取不同时期移植瘤作HE染色和抗人CD31免疫荧光标记。结果移植瘤大部分（81／96）存活，在移植后1～2个月期间体积明显增大，继而缓慢缩小。组织学观察显示移植瘤早期出现缺血改变，瘤性内皮细胞坏死、问质纤维化，约在移植后1个月出现瘤细胞增生，血管瘤增长，继而瘤内血管扩张，瘤性内皮细胞逐渐减少，血管瘤消退，代以纤维脂肪组织。结论将快速生长的人血管瘤组织移植于裸小鼠体内，移植瘤可存活，其缺血期后生长模式与人血管瘤自然发展过程相似。     

人参皂甙Rg3联合三氧化二砷对人肝癌细胞增殖性的影响

目的探讨人参皂甙Rg3联合三氧化二砷对肝癌裸鼠移植瘤模型的治疗作用,观察其对移植瘤肝癌细胞增殖性的影响。方法采用人肝癌细胞株Bel-7402细胞,种植于32只雄性裸鼠皮下,随机分成联合用药组、Rg3组(5mg/kg、10mg/kg、20mg/kg)、三氧化二砷组及对照组。实验自肿瘤接种第3天开始,人参皂甙Rg3(3个剂量),隔日灌胃,共20次;三氧化二砷40μg.kg-1.d-1,每日腹腔内注射,连续28d;对照组为生理盐水。停药1周后,脱颈处死,完整取出瘤块,检测肿瘤的重量,计算抑瘤率。采用免疫组织化学法检测增殖细胞核抗原(PCNA)在裸鼠肝癌移植瘤组织中的表达情况。结果三氧化二砷组抑瘤率(55.25%)高于Rg3组(5mg/kg亚组为32.24%、10mg/kg亚组为45.10%,20mg/kg亚组为50.00%),但随着Rg3浓度的升高,二者之间的差异明显减小;联合用药组中,5mg/kg亚组平均瘤重(0.58±0.15)g,抑瘤率61.84%;10mg/kg亚组平均瘤重(0.54±0.11)g,抑瘤率64.47%;20mg/kg亚组平均瘤重(0.49±0.12)g,抑瘤率67.76%,其抑瘤作用高于三氧化二砷组,差异有统计学意义(P<0.05)。三氧化二砷组抑制肝癌细胞增殖作用(PI值:38.3±5.3)强于Rg3组(PI值:5mg/kg亚组58.1±2.4;10mg/kg亚组51.8±5.3;20mg/kg亚组41.9±6.5),联合用药组(PI值:5mg/kg亚组38.6±8.4;10mg/kg亚组30.9±3.2;20mg/kg亚组23.3±3.3)作用最强(P<0.05),可以明显抑制移植瘤肝癌细胞增殖性。结论三氧化二砷对裸鼠肝癌移植瘤生长的抑制作用可能是通过抑制PCNA蛋白的表达。人参皂甙Rg3与三氧化二砷联合用药对移植瘤肝癌细胞增殖性的抑制有协同作用。     

Efficacy of suramin against human prostate carcinoma DU145 xenografts in nude mice

Purpose: Toward developing a model to study the mechanism of action of suramin against prostate cancer, we identified the effect of suramin on the growth of xenografts of the androgen-independent human prostate carcinoma DU145 cell line and our subline of suramin-resistant (SR) DU145 cells which are less responsive to suramin in vitro. Methods: Athymic nude mice bearing DU145 or SR DU145 xenografts were treated intraperitoneally (IP) once weekly with normal saline (vehicle control) or suramin in normal saline. For data analysis mice were grouped as follows: 0 mg/kg (controls), <210 mg/kg, 210 to 260 mg/kg, or gt;260 mg/kg suramin. Results: The growth of DU145 xenografts was slowed by treatment with 210 to 260 mg/kg suramin IP once weekly: differences in tumor volume for the 210 to 260 mg/kg group compared with the control group on days 29 and 57 showed growth inhibited by 43% and 55%, respectively. At the same time, growth of SR DU145 xenografts generally was not slowed by suramin treatment at any dose, but appeared to be enhanced to some degree by all doses of suramin during the typical slower initial growth phase of xenografts of this cell line: differences in tumor volume compared with control on day 29 showed growth enhanced by 100% to 342%. Mice treated with 210 to 260 mg/kg maintained nadir suramin plasma levels near our clinically relevant target of 1 × 10⁻⁴ M. Conclusions: Suramin, without concomitant corticosteroid therapy, was effective in slowing the growth of DU145 xenografts in nude mice at clinically relevant plasma suramin levels. The data showing efficacy for DU145 xenografts was supported by the lack of efficacy at the same time for xenografts of cells known to be less responsive to suramin in vitro, i.e. the SR DU145 cells, at similar doses and nadir plasma suramin levels. In discussions on the utility of suramin our data should be considered as support for continuing the study of suramin in the treatment of advanced, androgen-independent prostate cancer. Received: 9 March 1998 / Accepted: 29 June 1998     

鼻咽癌细胞株裸鼠移植瘤中癌细胞的凋亡

观察鼻咽癌细胞株ＣＮＥ－１和ＣＮＥ－２裸鼠移植瘤组织中肿瘤细胞凋亡的形态学特征,并探讨ｐ５３,ｂｃｌ－２和ｂａｘ在瘤细胞凋亡中所起的作用。方法：ＣＮＥ－１和ＣＮＥ－２鼻咽癌细胞株接种于裸鼠并在裸鼠体内连续传３代。     

Antitumor effect of monoclonal antibody-carboplatin conjugates in nude mice bearing human ovarian cancer cells

Background. The antitumor effect and toxicity of immunoconjugates were studied in nude mice bearing a human ovarian cancer cell line, OVA-1. Methods. We studied the tissue distribution of an anti-cytokeratin-8 monoclonal antibody (6D7) in OVA-1-bearing nude mice by giving 6D7 labelled with ¹²⁵I. The immuno conjugate consisted of 6D7 and carboplatin (6D7-conjugate), coupled via carboxymethyl dextran, and this was intraperitoneally administered to OVA-1 bearing nude mice. The tumor volume and the body weight were measured for 5 weeks. Tissue platinum concentrations in the OVA-1 tumor, blood, liver, kidney, and spleen, were measured from 3 to 120 min after administration of the conjugate. The results were compared with those in nude mice treated with nonspecific mouse IgG coupled with carboplatin (IgG-conjugate) or carboplatin alone. Results. The coupling rate of the drug to 6D7 was approximately 80%, and was stable over several measurements at various times. In-vivo accumulation of 6D7 labelled with ¹²⁵I in the OVA-1 tumors was significantly higher than that in mice that received nonspecific mouse- IgG-¹²⁵I, with tumor/ blood radioactivity ratios of 14.0 and 1.28, respectively. The tumor growth rate in mice that were administered 6D7-conjugate was (at a maximum) 40% lower than the tumor growth rate in mice administered carboplatin. The body weight of the mice that received 6D7-conjugate did not decrease during the 5-week observation period, while the body weight of the mice that received carboplatin decreased by a maximum of 10%. In addition, upon administration of 6D7-conjugate, the platinum concentration in the tumor was maintained for a longer period than after the administration of carboplatin alone. Conclusions. The tumor growth suppression effect was significantly higher in the mice bearing the OVA-1 tumor that received 6D7-conjugate than in the animals that received carboplatin alone. This difference could be caused by differences in the platinum concentrations in the tumor between the two groups. Received: November 9, 1998 / Accepted: March 23, 1999     

Preventive Effect of Matrix Metalloproteinase Inhibitor, R-94138, in Combination with Mitomycin C or Cisplatin on Peritoneal Dissemination of Human Gastric Cancer Cell Line TMK-1 in Nude Mice

R-94138, a matrix metalloproteinase inhibitor, was examined for the ability to prevent peritoneal dissemination of a human gastric cancer xenograft, TMK-1. When the supernatant of a co-culture of TMK-1 cells and human normal fibroblast cells was subjected to gelatin zymography, it was clear that the protein expression of MMP-2 had been inhibited by R-94138. When TMK-1 was injected intraperitoneally (i.p.) into nude mice at 5×10⁵ cells/body, the resulting peritoneal dissemination mimicked clinical carcinomatous peritonitis. When the maximum tolerated dose of mitomycin C (MMC) or cisplatin (DDP) was given 12 h after the tumor inoculation, peritoneal dissemination was completely inhibited, while the effect of R-94138 was limited when it was given i.p. at a dose of 20 mg/kg in a schedule of q.d. ×5 starting 12 h after tumor injection. MMC and DDP also suppressed peritoneal dissemination when they were administered 1 week after the tumor inoculation at a single dose of 2 and 3 mg/kg i.p., respectively. R-94138 inhibited peritoneal dissemination when it was administered i.p. at a dose of 30 mg/kg in a schedule of q.d. ×5 starting from 1 week after tumor injection. The combination of MMC and R-94138 increased the preventive effect on peritoneal dissemination. R-94138 seems to be a promising candidate to prevent peritoneal dissemination of gastric cancer.     

Fluorophore-conjugated anti-CEA Antibody for the Intraoperative Imaging of Pancreatic and Colorectal Cancer

Introduction  Colorectal and pancreatic cancers together comprise the third and fourth most common causes of cancer-related death in the United States. In both of these cancers, complete detection of primary and metastatic lesions at the time of surgery is critical to optimal surgical resection and appropriate patient treatment. Materials and Methods  We have investigated the use of fluorophore-labeled anti-carcinoembryonic antigen (CEA) monoclonal antibody to aid in cancer visualization in nude mouse models of human colorectal and pancreatic cancer. Anti-CEA was conjugated with a green fluorophore. Subcutaneous, orthotopic primary and metastatic human pancreatic and colorectal tumors were easily visualized with fluorescence imaging after administration of conjugated anti-CEA. The fluorescence signal was detectable 30 min after systemic antibody delivery and remained present for 2 weeks, with minimal in vivo photobleaching after exposure to standard operating room lighting. Tumor resection techniques revealed improved ability to resect labeled tumor tissue under fluorescence guidance. Comparison of two different fluorophores revealed differences in dose–response and photobleaching in vivo. Conclusion  These results indicate that fluorophore-labeled anti-CEA offers a novel intraoperative imaging technique for enhanced visualization of tumors in colorectal and pancreatic cancer when CEA expression is present, and that the choice of fluorophore significantly affects the signal intensity in the labeled tumor. These data were presented at the Society for Surgery of the Alimentary Tract meeting as part of the Digestive Diseases Week, San Diego CA, May 21 2008. Sharmeela Kaushal and Michele K. McElroy shared authorship. Work supported in part by: Cancer Therapeutics Training Program (T32 CA121938) National Institutes of Health (CA109949-03) American Cancer Society (RSG-05-037-01-CCE).     

Morphological and Cytogenetic Characterization and N-myc Oncogene Analysis of a Newly Established Neuroblastoma Cell Line

A permanent cell line established from a xenograft of neuroblastoma which occurred in a 5 year old girl was investigated for its morphological and biological characteristics. The cultured cells were tumorigenic in nude mice. Microscopically, each tumor consisted of small round to polygonal cells with irregular nuclei and prominent nucleoli, corresponding to the features of the primary and xenografted tumor cells. Electron microscopic examination revealed that both the transplanted tumor cells and the cultured cells contained scanty microtubules and dense-core neurosecretory granules. Chromosome analysis of this cell line showed monosomy for chromosomes 1,10,19 and X, and structural rearrangements involving chromosomes 8, 17 and 20, in addition to numerous double minutes. The N- myc oncogene was found to be amplified 40 to 80 fold in the transplanted and cultured tumor cells, as well as in the primary tumor cells. In situ hybridization with a digoxigenin labeled uridine-triphosphate N- myc RNA probe detected abundant mRNA in the tumor cells. This neuroblastoma line may become a valuable in vitro experimental model system for studies aimed at better characterization of neuroblastoma. Acta Pathol Jpn 41: 507 515, 1991.