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81.
目的 探索p16基因在脑胶质瘤发生发展过程中的作用及p16基因与肿瘤细胞放射敏感性间的关系。方法 将外源野生型p16基因导入胶质瘤细胞株U251、C6,筛选阳性克隆。同时以空载体质粒pCDNA3为对照,免疫组化检测p16基因表达,用MTT法测定细胞生长曲线及肿瘤杀伤率。结果 转染p16基因的U251、C6细胞有外源p16基因的整合及表达,克隆形成率减少,生长速度明显减慢,对辐射的敏感性增强。结论 导入外源野生型p16基因可抑制胶质瘤细胞恶性增殖,提高胶质瘤细胞对辐射的敏感性。 相似文献
82.
目的:探讨用局部扩大野的设野方法照射成人高分级脑胶质瘤的可行性。方法:经术后病理证实为Ⅲ~Ⅳ级星形细胞瘤53例,分为实验组(A组,25例)和对照组(B组,28例),放疗采用常规分割,总剂量DT50~65Gy,设野方法:A组用局部扩大野,B组用全脑加局部照射野。随访其放疗后生存期及1、3年生存率,复发率。并行统计学处理。结果:A、B组的中位生存期分别是14个月,15.5个月,1,3年生存率分别是80 相似文献
83.
建立大鼠C6脑胶质瘤模型与观察颅内肿瘤生长 总被引:13,自引:1,他引:12
建立大鼠C6脑胶质瘤模型,行一般观察和MRI检查以确定颅内肿瘤生长情况,寻找简易判定颅内肿瘤大小的可靠指标。方法体外培养大鼠C6胶质瘤细胞,应用立体定向法将含10g.L^-1琼脂糖和1*10^6C6细胞悬液10μL注入大鼠了尾状核。接种后行一般观察和MRL检查,对5组接种大鼠分别在第10,15,20,25日和自然死亡前做主动脉多聚甲醛灌注固定,对脑组织和肿瘤标本进行切片观察和HE染色。结果50只接 相似文献
84.
Cyclin A表达与人脑胶质瘤细胞增殖活性及其病理分级的关系 总被引:1,自引:1,他引:0
目的研究人脑胶质瘤中cyclin A表达与肿瘤细胞增殖活性及其病理分级的关系.方法采用免疫组化方法检测42例人脑胶质瘤标本中cyclin A和PCNA的表达水平,计算cyclin A阳性率和标记指数,以及PCNA阳性率和标记指数,分析它们与胶质瘤病理分级的关系.结果随着人脑胶质瘤病理分级的增高,cyclin A的阳性率和平均标记指数明显升高.在Ⅰ~Ⅳ级胶质瘤中其标记指数分别是(0.15±0.42),(1.59±1.95),(5.76±5.85)和(6.74±6.33);Ⅰ,Ⅱ级和Ⅲ,Ⅳ级间有显著性差异(P<0.01);其阳性率分别是11%,75%,71%和82%,在Ⅰ级与Ⅱ,Ⅲ,Ⅳ级间有显著性差异(P<0.05).PCNA标记指数随脑胶质瘤恶性程度提高而升高.Cyclin A与PCNA的表达呈正相关(r=0.858,P<0.01).结论人脑胶质瘤中cyclin A蛋白的阳性表达与细胞增殖活性和组织学分级密切相关,它可能参与了人脑胶质瘤细胞的恶性转化. 相似文献
85.
86.
Eiji Satoh Hirofumi Naganuma Atsushi Sasaki Mitsuyasu Nagasaka Hitoshi Ogata Hideaki Nukui 《Journal of neuro-oncology》1997,33(3):195-200
Glioblastoma cells secrete transforming growth factor- (TGF-), whichhas a variety of immunosuppressive properties. We investigatedthe effect of irradiation TGF- secretion by malignantglioma cells. Three malignant glioma cell lines (T98G,A172, KG-1-C) were cultured and irradiated using 10and 50 Gy Linac radiation. After further culturefor 36 hours in serum-free culture medium, thesupernatants were collected. The TGF- activity in theculture supernatants was determined using a specific bioassay.The levels of the active form and totalTGF- in the supernatants from irradiated malignant gliomacells decreased compared to those from un-irradiated cells.However, since irradiation inhibited the growth of tumorcells, the amount of TGF- secretion per cellin irradiated cells tended to increase after irradiation.These results suggest that malignant glioma cells canstill secrete TGF- and activate latent TGF- evenafter large dose irradiation, despite the inhibition oftumor growth. 相似文献
87.
Yang Weilian Barth Rolf F. Rotaru Joan H. Moeschberger Melvin L. Joel Darrel D. Nawrocky Marta M. Goodman Joseph H. 《Journal of neuro-oncology》1997,33(1-2):59-70
Boronophenylalanine (BPA) has been used for boron neutron capture therapy (BNCT) of brain tumors in both experimental animals and humans. The purpose of the present study was to determine if the efficacy of BNCT could be enhanced by means of intracarotid (i.c.) injection of BPA with or without blood-brain barrier disruption (BBB-D) and neutron irradiation using a rat brain tumor model. For biodistribution studies, F98 glioma cells were implanted stereotactically into the brains of Fischer rats, and12 days later BBB-D was carried out by i.c. infusion of 25% mannitol (1.373 mOsmol/ml), followed immediately by i.c. administration of 300, 500 or 800 mg of BPA/kg body weight (b.w.). At the 500 mg dose a fourfold increase in tumor boron concentration (94.5 g/g) was seen at 2.5 hours after BBB-D, compared to 20.8 g/g in i.v. injected animals. The best composite tumor to normal tissue ratios were observed at 2.5 hours after BBB-D, at which time the tumor: blood (T: Bl) ratio was10.9, and the tumor: brain (T: Br) ratio was 7.5, compared to 3.2 and 5.0 respectively for i.v. injected rats. In contrast, animals that had received i.c. BPA without BBB-D had T: Bl and T: Br ratios of 8.5 and 5.9, respectively, and the tumor boron concentration was 42.7g/g. For therapy experiments, initiated 14 days after intracerebral implantation of F98 glioma cells, 500 mg/kg b.w. of BPA were administered i.v. or i.c. with or without BBB-D, and the animals were irradiated 2.5 hourslater at the Brookhaven Medical Research Reactor with a collimated beam of thermal neutrons delivered to the head. The mean survival time for untreated control rats was 24 ± 3 days, 30 ± 2 days for irradiated controls, 37 ± 3 days for those receiving i.v. BPA, 52 ± 15 days for rats receiving i.c. BPA without BBB-D, and 95 ± 95 days for BBB-D followed by i.c. BPA and BNCT. The latter group had a 246% increase in life span (ILS) compared to untreated controls and a 124% ILS compared to that of i.v. injected animals. These survival data are the best ever obtained with the F98 glioma model and suggest that i.c. administration of BPA with or without BBB-D may be useful as a means to increase the efficacy of BNCT. 相似文献
88.
89.
Friedrich Weber Carsten Kremer Mario Klinkhammer Bettina Rasier Mario Brock 《Journal of neuro-oncology》1994,18(3):217-224
Summary This publication describes a new model to investigate the influence of tumor necrosis factor- (TNF-) on a three-dimensional glial cell aggregate under defined, standardized, reproducible conditions using the glioma cell line A 172.The cells are initially grown as normal monolayer culture until they reach a cell density of up to 1×106. Subsequently they are grown as spheroids by the liquid overlay technique. Spheroids grown in this way were divided into ten groups of more than 50 cell aggregates. Three groups were coincubated with free TNF- in increasing dosages (100 ng/ml, 200 ng/ml and 1000 ng/ml); three groups were incubated with empty liposomes (0.2 mg/ml, 0.4 mg/ml and 2 mg/ml); three groups received liposomes which had been loaded with TNF-, and one group, which received no treatment, served as control.The diameter of the spheroids ranged from 80 m to 350 m. There was no significant difference in growth between the 3 groups treated with free TNF-. Comparing spheroids treated with TNF- with those which had been coincubated with empty liposomes, there was a significant difference (p<0.001) in growth, which correlated with the amount of liposomes. Similarly, free TNF- had a significantly (P<0.001) stronger growth-inhibiting effect as compared to liposomes loaded with TNF-. Comparing the groups treated with liposomes only to those treated with liposomes loaded with TNF-, the latter exhibited a more marked (although not significantly) growth-inhibiting effect.The preliminary conclusion is that the major growth-inhibiting effect seems to be mediated by the liposomes. This phenomenon is in agreement with results obtained in monolayer cultures. 相似文献
90.
Motonobu Kameyama Kiichi Ishiwata Yuji Tsurumi Jun Itoh Kiyotaka Sato Ryuichi Katakura Takashi Yoshimoto Jun Hatazawa Masatoshi Ito Tatsuo Ido 《Journal of neuro-oncology》1995,23(1):53-61
Summary Positron emission tomography was used to investigate the metabolism of nucleic acids by18F-fluoro-2-deoxyuridine (18F-FUdR) in 22 patients with gliomas. Sixteen cases of high grade glioma clearly demonstrated a region of high activity with a differential absorption rate (DAR) of 0.64 ± 0.34. Six cases of low grade glioma failed to reveal a positive image of the tumor and the DAR in tumor was 0.21 ± 0.042 (p < 0.01). This PET-18F-FUdR study succeeded in differentiating high and low grade gliomas from the view point of nucleic acid metabolism. 相似文献