原位膀胱癌大鼠建模方法比较及超声鉴定方法

目的通过对大鼠分别给予N-正丁基-N-(4-羟基-丁基)亚硝胺[N-butyl-N-(4-hydroxybutyl)nitrosamine,BBN]饮水饲养和N-甲基亚硝基脲(N-methyl-nitrosourea,MNU)膀胱灌注,来比较两种方法的造模效果以及各自的优缺点。判断B型高频超声对大鼠原位膀胱癌的诊断价值。方法BBN组大鼠给予0.05%的BBN溶液连续喂养6周,后更换为2%的枸橼酸钠溶液连续喂养22周,第28周末为诱导终点。MNU组大鼠给予MNU溶液(20mg/ml)膀胱灌注,每两周1次,每次0.1ml/只,连续灌注8周,后再常规喂养6周,第14周为诱癌终点。分别于第28周末(BBN组)和第14周末(MNU组)对两组大鼠进行超声扫描诊断,并在处死后取膀胱组织行病理学观察。比较两组的存活率和存活成瘤率。结果 BBN诱癌组20只大鼠28周后存活11只,成瘤8只,存活率为55%,存活成瘤率为72.7%。MNU组20只大鼠14周后存活18只,成瘤17只,存活率为90%,存活成瘤率为94.4%。结论利用MNU膀胱灌注行大鼠膀胱癌造模,其存活率和存活成瘤率均显著高于BBN饮水饲养造模。超声可作为大鼠膀胱癌造模活体检测的可靠方法。     

N-甲基亚硝基脲诱导大鼠膀胱肿瘤作用的动态观察

目的　观察N 甲基亚硝基脲 (MNU)诱发Wistar大鼠膀胱癌的作用及动态过程。方法　MNU大鼠膀胱灌注 2mg/次 ,1次 /2周 ,共 4次。分别观察实验第 3、6、9、12和 14周时膀胱黏膜的改变、并作尿吖啶橙 (AO)荧光染色。结果　膀胱灌注 3周出现不典型增生或腺性膀胱炎 ,6周时有原位癌改变 ,9周时膀胱内有明显癌性肿块 ,12～ 14周为膀胱乳头状癌或浸润性癌 ,9周时的致癌率 10 0 .0 % ,组织学改变及病理学特征与人膀胱癌十分相似。AO染色诊断大鼠膀胱癌的阳性率为 77.0 %。结论　MNU灌注诱导大鼠膀胱癌方法简便、可靠 ,致癌过程经历上皮增生、乳头状瘤形成和癌变动态变化。     

建立膀胱癌细胞系BIU-87原位移植瘤模型的实验研究

目的 探讨建立人体膀胱癌细胞系BIU-87膀胱原位移植瘤模型的有效方法,为膀胱癌实验动物的相关研究提供理论基础.方法 BALB-C系裸鼠20只,分成A、B两组(各10只),A组采用手术方法于膀胱壁内注射人体膀胱癌细胞系BIU-87,B组经膀胱灌注人体膀胱癌细胞系BIU-87,分别观察不同阶段两组裸鼠膀胱肿瘤的发生发展情况.实验终点(4周)处死裸鼠,进行瘤体大小及组织学检测.结果 A组裸鼠中,一只于术后第2d死亡,其余存活9只中,8只成瘤,成瘤率为89％;B组10只均未成瘤.结论 经膀胱灌注不能建立理想的膀胱原位移植瘤模型,手术方法建立膀胱原位移植瘤模型的效果确切,能较好地模拟人膀胱肿瘤的疾病发展过程,对国人膀胱肿瘤的研究具有一定应用价值.     

B7-H1 与B7-H4 在膀胱癌大鼠及其癌旁组织中的差异表达

目的:研究膀胱原位癌组织及癌旁组织中共刺激分子 B7-H1与 B7-H4的表达情况,并分析二者的相关性。方法:采用 N-亚硝基 -N-甲基脲(MNU)溶液膀胱灌注法制备膀胱癌大鼠模型(30只),处死大鼠,获取癌组织及癌旁组织,进行病理检查;采用生理盐水溶液膀胱灌注法作为对照组( 12只),处死大鼠,获取膀胱组织,进行病理学检查;采用 RT-PCR技术分别检测对照组大鼠膀胱组织( A组)、膀胱癌模型组癌组织( B组)及模型组癌旁组织( C组)中 B7-H1与 B7-H4的 mRNA的表达水平,并分析二者之间的相关性。结果: 30只膀胱癌模型组大鼠, 28只模型制备成功,造模成功率 93.3%。A组、C组 B7-H1、B7-H4 mRNA表达量均明显低于 B组(0.71±0.38、0.79±0.21 vs 1.44±0.67;0.84±0.22、     

大鼠原位膀胱癌模型的建立及CT鉴定方法

目的研究N-甲基亚硝基脲(N-methyl-nitrosourea,MNU)诱导大鼠原位膀胱癌模型的建立及CT鉴定方法。方法 50只SD大鼠随机分为两组,对照组(A组)15只,实验组(B组)35只。A组大鼠经尿道膀胱内灌注生理盐水,每两周一次,每次0.1ml,共4次。B组大鼠用MNU以同样的方法灌注,每次0.2mg。于第14周末对两组大鼠进行膀胱CT扫描诊断,并且处死后取膀胱组织行病理学观察。结果A组13只大鼠经CT扫描未发现膀胱肿瘤,病理检查未见肿瘤组织。B组28只大鼠CT扫描膀胱均见明显异常,表现为膀胱壁局部肿块突起或不规则增厚、密度不均,病理诊断均为膀胱癌。结论MNU诱导大鼠原位膀胱癌模型是一种较为简单、可靠的建模方法。活体大鼠膀胱CT扫描与病理学结果有高度一致性,可作为该模型的活体鉴定方法。     

化学致癌物诱导的膀胱癌的超声及形态学特点

化学致癌物诱导的啮齿类动物的膀胱癌模型，与临床上膀胱癌的发生比较类似，因此其已成为评价膀胱癌新疗法的重要模型。该模型最大的弊端是对活体动物以及尸检时难以评估负荷瘤的生长状况。本作为解决这一问题，提供了简便、准确的方法。对60只雌性Wistar大鼠的饮水中添加0．05％N-丁基-N-（4-羟基丁基）亚硝胺（BBN），饲养35周，并定期超声检查麻醉大鼠膀胱中有无肿瘤发生。处死大鼠，称量肿瘤重量，数字化测量肿瘤大小，并进行组织病理学分析。发现在饮用含BBN饮水第5周时就出现尿路上皮点灶状过度增生，15周时出现重度异常增生，20周后形成移行细胞癌。数字化测量系统可辨别直径1mm的小肿瘤。     

γ-亚麻酸膀胱灌注治疗大鼠膀胱癌的实验研究

为了探讨γ-亚麻酸诱导大鼠膀胱癌细胞凋亡的机制,我们采用γ-亚麻酸对膀胱癌荷瘤大鼠行膀胱灌注,观察灌注前后肿瘤细胞中丙二醛(MDA)浓度的变化,增殖细胞核抗原(PCNA)以及Fas和FasL的表达情况,现报告如下. 材料与方法 8～10周龄SPF级雌性SD大鼠60只,体质量250～300 g,由上海斯莱克实验动物有限责任公司提供.应用N-甲基亚硝基脲(MNU,美国Sigma公司)膀胱灌注,9周后诱导出大鼠膀胱癌动物模型[1].1％戊巴比妥钠腹腔内注射麻醉,手术切取部分膀胱癌组织,缝合膀胱.术后1周,60只大鼠随机分为2组,每组30只.实验组:膀胱灌注浓度为2.5 mg/ml的γ-亚麻酸(美国Sigma公司),每只每次用量0.4 ml(1mg/次),保留2h.隔日1次,共3次.     

C57BL／6小鼠原位膀胱肿瘤模型的建立

目的建立C57BL／6小鼠原位膀胱肿瘤模型。方法硝酸银膀胱黏膜处理、MB49膀胱灌注法建立C57BL／6小鼠原位膀胱肿瘤模型。结果三组小鼠中,7d组10只小鼠有9只成瘤,10d组和15d组20只小鼠全部成瘤。总成瘤率96．7％。结论硝酸银膀胱黏膜处理、MB49膀胱灌注法建立的CS7BL／6小鼠原位膀胱肿瘤模型操作简单,成瘤率高,是一种理想的、有实际应用前景的小鼠原位膀胱肿瘤模型。     

PI3-K抑制剂LY294002增强丝裂霉素C对大鼠原位膀胱癌抑制作用的研究

目的 研究PI3-K抑制剂LY294002在大鼠体内应用时对膀胱灌注化疗药物丝裂霉素C(mitomycin C,MMC)的协同抑癌作用以及毒副作用.方法 对荷原位膀胱癌的大鼠进行膀胱内灌注生理盐水、MMC、LY294002,记录大鼠体重变化、CT动态观察膀胱肿瘤变化、处死后直接测量膀胱肿瘤大小及观察灌注治疗完成后的存活率.结果 MMC联合LY294002灌注治疗4周后,荷膀胱癌大鼠平均体重明显高于单独MMC治疗组,CT扫描显示MMC联合LY294002灌注治疗对膀胱肿瘤的抑制作用强于单独MMC灌注.MMC联合LY294002灌注治疗4周后,大鼠膀胱内肿瘤直径小于单独MMC灌注组.灌注治疗4周后,各组大鼠存活率差异无统计学意义.LY294002灌注治疗会导致大鼠一过性的体重下降,无其他严重不良反应发生.结论 LY294002能增强MMC对大鼠膀胱癌的抑制作用,LY294002在大鼠体内应用时无严重不良反应发生.     

奥曲肽对二乙基亚硝胺诱导的大鼠肝癌的影响

目的 研究生长抑素类似物奥曲肽(oetreotide,OCT)抑制大鼠诱导肝癌形成的效果及其机制.方法 用二乙基亚硝胺溶液(DENA)诱导大鼠肝癌模型,随机分成OCT治疗组和对照组,观察两组大鼠存活情况和肝癌发生率,用免疫组化和半定量RT-PCR的方法检测肝脏和肝癌组织中生长抑素受体2(somatostatin receptor 2,SSTR2)蛋白和Mrna的水平.结果 OCT组的存活率70.0%(7/10)明显高于对照组30.0%(6/20)(x2=4.344,P＜0.05);DENA喂养16周的诱癌率,OCT组(0%,0/10)低于对照组(30.0%,6/20),但两组比较差异无统计学意义(X2=3.750,P＞0.05);DENA喂养22周的诱癌率,OCT组(22.2%,2/9)显著低于对照组(83.3%,10/12)(X2=7.843,P＜0.01).SSTR2mRNA和蛋白表达随肝硬化加重而增加,DENA喂养16周时最强,DENA喂养22周时明显下降,肝癌内的表达更低于周边组织(分别F=35.010和13.386,均P＜0.01);OCT治疗组DENA喂养8周和16周后的SSTR2mRNA和蛋白水平均近似于对照组,但DENA喂养22周时两者的水平均无明显下降,明显高于同期对照组(分别t=2.806和4.498,均P＜0.05).结论 OCT能有效地抑制大鼠肝癌的形成,并减少诱癌大鼠的死亡率,SSTR2表达的维持可能是OCT发挥作用的关键.     

Effect of sex hormones on development of urinary bladder tumours in rats induced by N-butyl-N-(4-hydroxybutyl) nitrosamine

Male and female Wistar strain rats were given 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in their drinking water for 6 weeks and then water without BBN for 18 weeks. Diethylstilbestrol and testosterone were implanted subcutaneously into both intact and gonadectomised animals before or after treatment with BBN to evaluate their effects on the development of bladder tumours. Diethylstilboestrol reduced the incidence of bladder tumours significantly in male rats. The incidence was higher in female rats after spaying and administration of testosterone after BBN treatment, than in the intact female. These results suggest that diethylstilboestrol inhibits carcinogenesis of the urinary bladder induced by BBN and growth of bladder tumours induced by BBN, in male rats. On the other hand, testosterone seems to stimulate the growth of bladder tumours induced by BBN in female rats.     

Rat urinary bladder carcinomas induced by N-butyl-N-(4-hydroxybutyl)-nitrosamine and N-methyl-N-nitrosourea

Summary The present investigation was conducted to examine the combination effect of N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) and N-methyl-N-nitrosourea(MNU) in rat urinary bladder carcinogenesis. Experiment 1 was performed in the groups treated by oral BBN administration in combination with MNU intraversical instillation and their control groups. In the groups given both BBN and MNU, the ratio of rats with the nonpapillary type to carcinoma-bearing rats was significantly higher than in the controls. Since most of the carcinomas were non-invasive, the observation period was prolonged in the groups given both BBN and MNU in experiment 2. However, even after a longer observation period, no invasive carcinoma was observed. These results suggest that high-grade and invasive carcinomas similar to those induced by BBN and MNU in the heterotopically transplanted rat bladder cannot be induced in the natural bladder of the rat.     

n-3 PUFAs对MNU诱发大鼠结直肠癌形成的影响及机制

目的：探讨n-3多不饱和脂肪酸（n-3 PUFAs）对N-甲基-N-亚硝基脲（MNU）诱发大鼠结直肠癌模形成的影响及机制。方法：将60只SD大鼠随机均分为实验组和对照组。两组均用MNU进行灌肠诱导结直肠癌,实验组同时行n-3 PUFAs灌胃,而对照组以等量生理盐水灌胃。16周后,比较两组大鼠的一般情况;处死大鼠,观察肿瘤发生情况及肿瘤病理特征,气相色谱测定红细胞膜n-3 PUFAs浓度,液相色谱串联质谱检测外周血细胞总DNA甲基化水平。结果：实验组大鼠便血发生率低于对照组、进食量及体质量大于对照组（均P<0.05）。两组大鼠均有结直肠肿瘤形成,肿瘤均为腺癌,但与对照组比较,实验组结直肠肿瘤形成率明显降低（63.33% vs. 86.67%,P<0.05）,且肿瘤最大径小、多发肿瘤少。实验组大鼠红细胞膜n-3 PUFAs浓度、外周血细胞总DNA甲基化水平明显高于对照组（均P<0.05）。结论：n-3 PUFAs能有效抑制MNU诱导的大鼠结直肠癌发生,可能与其提高DNA甲基化水平有关。

     

Effects of LH-RH analogue on pituitary-testicular axis and bladder carcinogenesis of BBN administered male rats

As a first step of investigating male predominance of bladder cancer incidence, we have studied relationships between rat bladder carcinogenesis, induced by BBN, and changes of pituitary-testicular axis, induced by a LH-RH analogue. The rats were divided into the following five groups. The first group (Age matched control group) was given normal drinking water for 30 weeks. The 2nd group (BBN group) was given a drinking water containing 0.05% BBN for 6 weeks. The 3rd group (LH-RH group) was given subcutaneous injections of a LH-RH analogue depot every four weeks. The 4th group (LH-RH + BBN group) was given subcutaneous injections of the LH-RH analogue depot every four weeks and a drinking water containing 0.05% BBN for 6 weeks. The 5th group (castration group) was castrated and given normal drinking water. The results were summarized as follows. 1) Serum LH, FSH and testosterone levels reached their peaks one day after the LH-RH analogue injection and decreased afterwards. Testosterone marked a castration level one week after the LH-RH analogue injection. 2) There was no significant difference between the BBN and non BBN groups in serum LH, FSH and testosterone levels. Thus, BBN did not influence the pituitary-testicular axis and the action of the LH-RH analogues. 3) Incidence of cancer was higher in the group of BBN + LH-RH than in the group of BBN 8 weeks after the start of the experiment. Then, the incidence was reversed between 20 weeks and 26 weeks; finally it became almost the same at 30 weeks. This phenomenon may be explained by the experimented schedule we applied; that is, BBN and LH-RH analogue were administered simultaneously. 4) Thus, changes of the pituitary-testicular axis induced by the LH-RH analogue seemed to have influence on bladder carcinogen.     

环孢素对大鼠膀胱肿瘤细胞增殖、凋亡和新生血管形成的影响

目的 探讨环孢素对N-丁基-N-(4-羟丁基)亚硝胺(BBN)诱导的大鼠膀胱肿瘤细胞增殖、凋亡及肿瘤新生血管形成的影响.方法实验组大鼠10只在用BBN诱导膀胱肿瘤的同时用环孢素进行药物干预,对照组大鼠10只仅用BBN诱导膀胱肿瘤.取2组大鼠膀胱标本免疫组化方法检测肿瘤增殖细胞核抗原(PCNA)表达情况,计算肿瘤细胞增殖指数;TUNEL方法检测肿瘤细胞凋亡情况,计算肿瘤细胞凋亡指数;免疫组化方法检测肿瘤CD31表达情况,计算肿瘤微血管密度(MVD).结果 实验组和对照组肿瘤细胞增殖指数分别为(35.3±8.6)%和(28.7±8.0)%,P＜0.05;凋亡指数分别为(2.5±0.8)%和(4.3±1.3)%,P＜0.05;微血管密度分别为32.5±8.2和26.3±8.1,P＜0.05.结论 环孢素可能通过影响肿瘤细胞增殖、凋亡和肿瘤新生血管形成等机制对膀胱肿瘤生长产生促进作用.     

Promoting the effects of intravesical instillation of saline on bladder lesion development in rats pre-treated with BBN

BACKGROUND: At present, immunotherapeutic agents such as bacillus Calmette-Guerin (BCG) and anti-tumor chemotherapeutic agents in saline are used intravesically in patients with bladder carcinoma. However, of greater significance is the possibility that the saline vehicle may itself promote carcinoma development in the bladder. METHODS: The potential promoting effects of intravesical instillation of saline were assessed in female F344 rats. The animals were divided into 3 groups, all of which received 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in their drinking water for the first 10 weeks. They were then maintained without further treatment (group 1) or received intravesical instillations of 0.3 mL of saline or distilled water once a week for 6 weeks, 15 weeks after the end of the BBN treatment (groups 2 and 3). At 32 weeks, all the animals were killed and examined immunohistochemically with proliferating cell nuclear antigen (PCNA) antibody, as well as by routine histopathologic examination. RESULTS: Both the incidence and the number of bladder carcinomas were higher in the animals that received instillations of saline than in those who did not receive the instillations. Significant increases in tumor size were also noted for the saline-treated groups, although this was not linked with the PCNA labeling index. CONCLUSIONS: The results indicate that saline is a promoter of urinary bladder carcinogenesis either because of the catheterization or the fluid itself.     

Promotive effects of intravesical instillation of dimethylsulfoxide on bladder carcinogenesis in mice]

The effect of intravesical instillation of dimethylsulfoxide (DMSO) on bladder carcinogenesis was examined in mice. Experiment 1: Fifty-five female C3H/He mice were administered 0.05% N-butyl-N-(4-hydroxy-butyl) nitrosamine (BBN) in their drinking water for 8 weeks. In week 9 they were divided into two groups consisting of 25 mice each. Then, under nembutal anesthesia the first group was given weekly intravesical inatillations of 0.1 ml DMSO (minimum 99.0%) for 10 weeks. The second group received no treatment except anesthesia. All mice were killed 30 weeks after the begining of the experiment and their urinary bladder resected for histological examination. The incidence of bladder carcinoma was 93.7% (15.16) and 27.7% (6/22) in groups 1 and 2, respectively. These incidences differed significantly between the two groups. Experiment 2: One hundred and twenty female C3H/He mice were divided into two groups. The first group was given 0.05% BBN in their drinking water for 5 weeks and then tap water. The second group was not given BBN. In week 6, the first group was divided again into three groups (1, 2 and 3) consisting of 28, 26, and 27 mice, respectively. The second group was divided into groups 4 and 5 consisting of 21 and 18 mice, respectively. Under nembutar anaesthesia groups 1 and 4 received weekly intravesical instillation of 0.05 ml DMSO (minimum 99.0%) from weeks 6 to 13, Group 2 received weekly intravesical instillation of 0.05 ml distilled water from weeks 6 to 13. Groups 3 and 5 received no treatment except anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Antitumour effects of the angiogenesis inhibitor AGM-1470 on rat urinary bladder tumours induced by N-butyl-N-(4-hydroxybutyl) nitrosamine

OBJECTIVE: To examine the antitumour effects of the angiogenesis inhibitor AGM-1470 (TNP-470) on rat urinary bladder tumours induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). MATERIALS AND METHODS: Fischer-344 rats were allocated to one of four groups of 15 rats each; in group 1, rats were administered AGM-1470 intraperitoneally, with group 2 acting as the control and given only saline; in group 3, AGM-1470 was instillation intravesically and group 4 acting as control (intravesical saline). All rats were given 0.05% BBN in their drinking water for 8 weeks and then given water with no BBN. AGM-1470 was administered at a dose of 30 mg/kg every other day for 6 weeks in group 1 and at 15 mg/kg once a week for 6 weeks in group 3. This treatment was commenced at 21 weeks after the start of BBN treatment, when tumorigenesis was apparent in all rat bladders; approximately 70-80% of the tumours were carcinomas. All rats were killed in the 27th week. The antitumour effects of AGM-1470 on the BBN-induced bladder tumours were evaluated macroscopically and histologically. The inhibitory effect of AGM-1470 on endothelial cell proliferation was assessed in groups 1 and 2 by immunohistochemical staining for Factor VIII-related antigen and by counting the microvessels. RESULTS: The number and volume of bladder tumours were significantly less in group 1 than group 2. In the latter, at least one bladder tumour developed in each of the 15 rats. Histologically, transitional cell carcinoma (TCC) was found in 13 rats and papilloma in two, with invasive cancer in three of the 13 TCCs. Bladder tumours developed in only four of the 15 rats in group 1. Carcinomas were found in three of these four rats and no invasive cancer was detected. The rats in group 1 had significantly fewer microvessels than the controls. The rats in group 4 also showed slightly but insignificantly less tumour growth and fewer carcinomas. In neither experiment were any major side-effects seen except for mild weight loss after AGM-1470 treatment. CONCLUSION: AGM-1470 inhibited the growth and malignant progression of BBN-induced bladder tumours in rats, apparently mainly by the inhibition of tumour vessel development. The intraperitoneal administration of AGM-1470 produced better results than did intravesical instillation. These results suggest that the angiogenesis inhibitor AGM-1470 is a promising agent for the treatment of human bladder cancer.     

Preventive effects of urinary bladder tumors induced by N-butyl-N-(4-hydroxybutyl)-nitrosamine in rat by green tea leaves

BACKGROUND: Recently, the anticarcinogenic effects of green tea have been studied in sites other than the urinary tract. Although the incidence of bladder cancer has increased, responses to therapy have been limited. The present work examined the preventive effects of green tea against bladder tumors induced in rats by the carcinogen, N-butyl-N-(4-hydroxybutyl)-nitrosamine(BBN). METHODS: From week 5 to week 9, all the groups were exposed to 0.05% BBN in the drinking water for 5 weeks. Rats were divided into four groups. Group 1 was fed a CE-2 diet and tap water for the entire experimental period and served as the control group. Group 2 was fed the green tea leaves after carcinogen exposure. Groups 3 and 4 received green tea leaves before carcinogen exposure. All rats were killed and examined at 44 weeks. RESULTS: Green tea leaves prevented the growth of BBN-induced urinary bladder tumors when given before the carcinogen. CONCLUSION: Green tea may inhibit tumor initiation in the bladder.