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Sample records for c6 glioma model

  1. Establishment of C6 brain glioma models through stereotactic technique for laser interstitial thermotherapy research

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    Jian Shi

    2015-01-01

    Conclusion: The rat C6 brain glioma model established in the study was a perfect model to study LITT of glioma. Infrared thermograph technique measured temperature conveniently and effectively. The technique is noninvasive, and the obtained data could be further processed using software used in LITT research. To measure deep-tissue temperature, combining thermocouple with infrared thermograph technique would present better results.

  2. Boronophenylalanine uptake in C6 glioma model is dramatically increased by L-DOPA preloading

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    Capuani, S. [CNR-INFM SOFT, Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, Rome (Italy); Enrico Fermi Center, Compendio Viminale, Rome (Italy)], E-mail: silvia.capuani@roma1.infn.it; Gili, T. [CNR-INFM SOFT, Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, Rome (Italy); Enrico Fermi Center, Compendio Viminale, Rome (Italy); Bozzali, M. [Neuroimaging Laboratory, Santa Lucia Foundation, Via Ardeatina 306, Rome (Italy); Russo, S. [Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London (United Kingdom); Porcari, P. [CNR-INFM SOFT, Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, Rome (Italy); Cametti, C. [CNR-INFM SOFT, Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, Rome (Italy); Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, Rome (Italy); Muolo, M. [Department of Biological Science, University ' Rome III' , Viale G. Marconi 446, Rome (Italy); D' Amore, E. [Serv. Qual./Sicurezza Sperim. Anim., Istituto Superiore di Sanita, Rome (Italy); Maraviglia, B. [Enrico Fermi Center, Compendio Viminale, Rome (Italy); Neuroimaging Laboratory, Santa Lucia Foundation, Via Ardeatina 306, Rome (Italy); Lazzarino, G. [Laboratory of Biochemistry, Department of Chemical Sciences, University of Catania, Viale A. Doria 6, Catania (Italy); Pastore, F.S. [Department of Neuroscience, Institute of Neurosurgery, University ' Tor Vergata' , Via Montpellier 1, Rome (Italy)

    2009-07-15

    One of the main limitations for BNCT effectiveness is the insufficient intake of {sup 10}B nuclei within tumour cells. This work was aimed at investigating the use of L-DOPA as enhancer for boronophenylalanine (BPA) uptake in the C6 glioma model. The investigation was first performed in vitro, and then extended in vivo to the animal model. BPA accumulation in C6 glioma cells was assessed, using radiowave dielectric spectroscopy (RDS), with and without L-DOPA preloading. C6 glioma cells were also implanted in the brain of 25 rats, randomly assigned to two experimental branches: (1) intra-carotid BPA infusion; (2) intra-carotid BPA infusion after pre-treatment with L-DOPA, administrated 24 h before BPA infusion. All animals were sacrificed, and assessment of BPA concentrations in tumour tissue, normal brain, and blood samples was performed using high performance liquid chromatography (HPLC). L-DOPA preloading induced a massive increase of BPA concentration either in vitro on C6 glioma cells or in vivo in the animal model tumour. Moreover, no significant difference was found in the normal brain and blood samples between the two animal groups. This study suggests the potential use of L-DOPA as enhancer for BPA accumulation in malignant gliomas eligible for BNCT.

  3. Combination hyperbaric oxygen and temozolomide therapy in c6 rat glioma model Terapia combinada de oxigênio hiperbárico e temozomida no modelo C6 de glioma em ratos

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    Yaşar Dagıstan

    2012-06-01

    Full Text Available PURPOSE: Temozolomide (TMZ has anti-tumor activity in patients with malignant glioma. Hyperbaric oxygen (HBO may enhance the efficacy of certain therapies that are limited because of the hypoxic tumor microenvironment. We examined the combined effects of TMZ-HBO in a rat glioma model. METHODS: After stereotactic injection of C6/LacZ rat glioma cells into the Wistar rats brain, the rats were randomly assigned to three treatment groups [group 1, control treatment; group 2, TMZ alone; group 3, a combination of TMZ and HBO]. Rats were sacrificed 18 days after treatment, and number of intra-/peri-tumoral vessels, microendothelial proliferations, immunohistochemistry and necrotic area were evaluated. RESULTS: Tumoral tissue was stained only sparsely with GFAP. Temozolomide treatment was significantly decreased in tumor tissue intratumoral vessel number / total tumor area level. The level of Ki67 was significantly decreased in the tumor tissue of the group 3. Additionally, the total necrotic area / total tumor volume (% was decreased significantly in tumor tissue of the group 3 rats compared to group1 and 2. CONCLUSION: The combination of hyperbaric oxygen with temozolomide produced an important reduction in glioma growth and effective approach to the treatment of glioblastoma.OBJETIVO: A temozolomida (TMZ tem atividade anti-tumoral em pacientes com glioma maligno. Oxigênio hiperbárico (HBO pode aumentar a eficácia de terapias que são limitadas devido a um microambiente do tumor hipóxico. Foram examinados os efeitos combinados de TMZ-HBO em um modelo de glioma em rato. MÉTODOS: Após a injeção estereotáxica de células de glioma de rato C6/LacZ no cérebro de ratos Wistar, os ratos foram distribuídos aleatoriamente em três grupos de tratamento: Grupo 1: tratamento de controle. Grupo 2: TMZ sozinho. Grupo 3: uma combinação de TMZ e HBO. Os ratos foram sacrificados 18 dias após o tratamento. Foram avaliados o número de vasos intra

  4. C6大鼠脑胶质瘤动物模型建立及病理观察%Animal Model Establishment and Pathological Observation of C6 Cerebral Glioma in Rats

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    张荣; 段美美

    2013-01-01

    Objective To establish the simple, feasible, reliable and stable C6 cerebral glioma model in rats so as to provide the platform for the stud)' of the pathogenesis and the method of prevention and treatment of cerebral glioma. Methods The stereotaxic technique was adopted. C6 glioma cells in rats cultured in vitro were condensed and placed in suspension. C6 glioma cells( containing 2. 5 × 106 C6 cells/25 μL )were implanted into the right caudate nucleus in SD rats. The survival conditions of the rats were consecutively observed. Separately, in the 7th, 14th and 21sl days of the implantation, the rats were sacrificed and the brains were collected to prepare the pathological sections. With HE staining, they were observed under light -microscope. Results In about 7 days,after C6 glioma cells implanted,the survival state of rats was good. In about 14 days, the intracranial hypertension was apparent. In about 21 days, most of the rats were in critical condition. In the gross specimen examination, except the accidental death of 3 rats, the tumor formation rate was 100% in the rest of 18 rats. Along with the aging of the rats, the tumor size was enlarged, the midline structure was migrated obviously and the occupied effect was getting marked. HE staining discovered the significant formation of cerebral glioma in the rats. Conclusion The animal model of C6 rat cerebral glioma is reliable and stable. The tumor growth property and pathological characteristics are similar to human cerebral glioma. Hence,the model is applicable satisfactorily for the clinical basic research of glioma.%目的 建立简单易行、可靠稳定的大鼠C6脑胶质瘤模型,为研究脑胶质瘤的发病机制和防治方法提供操作平台.方法 采用立体定向技术,将体外培养的大鼠C6胶质瘤细胞浓缩悬置,2.5×106 个·25 μL-1接种于SD大鼠的右侧尾壳核区,种植后连续观察大鼠的生存状态,并分别于7、14、21 d处死大鼠,立刻取脑,制作病理切

  5. Effects of endostatin on C6 glioma-induced edema

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    YANG Li-juan; LIN Zhi-xiong; KANG De-zhi; WENG Shen-mei; LIN Jian-hua; HUANG Qiang; ZHANG Peng-fei

    2011-01-01

    Background Glioma-induced edema is considered as one of the most pathological characteristics of glioma and a significant source of morbidity and mortality.New strategies are needed for the treatment of peritumoral edema in glioma.Endostatin has been proven to be beneficial as an anti-angiogenic agent in experimental gliomas,but the effects are unclear.This study aimed to investigate the effects of endostatin on C6 glioma-induced edema.Methods Tumorigenic mice were established by subcutaneous injection of three glioma cell lines,C6-null cells and stable transfected-C6 cells overexpressing mock vector (C6-mock cells) and endostatin (C6-endo cells).Endostatin expression in xenograft C6 glioma was determined by immunostaining and Western blotting.Glioma-induced edema and tumor vessel permeability were assayed.The effect of endostatin on vascular enodothelial growth factor (VEGF) expression in vivo was analyzed by quantitative polymerase chain reaction (Q-PCR) and enzyme-linked immunosorbent assay (ELISA).The number of vesiculo-vascuolar organelles (VVOs) formed in tumor endothelia was calculated using electron microscopy.Data were analyzed by using one-way analysis of variance (ANOVA) followed by Dunnett's post hoc test for multiple comparisons to the control groups.Results Overexpression of endostatin (C6-endo cells) significantly suppressed tumor growth and reduced tumor edema and vessel permeability.ELISA analysis showed that the level of VEGF protein was markedly decreased in tumor from C6-endo cells compared with tumor from C6-null cells and C6-mock cells.Similar results were obtained by Q-PCR.Furthermore,the number of VVOs observed in tumor from C6-endo mice was significantly reduced compared with tumor from C6-null cells or C6-mock cells.Conclusions Our data provide primary evidence that endostatin reduces glioma-induced edema and vascular permeability.Using endostatin may be an effective strategy for treating glioma edema.

  6. Extracellular diffusion quantified by magnetic resonance imaging during rat C6 glioma cell progression

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    G. Song

    Full Text Available Solution reflux and edema hamper the convection-enhanced delivery of the standard treatment for glioma. Therefore, a real-time magnetic resonance imaging (MRI method was developed to monitor the dosing process, but a quantitative analysis of local diffusion and clearance parameters has not been assessed. The objective of this study was to compare diffusion into the extracellular space (ECS at different stages of rat C6 gliomas, and analyze the effects of the extracellular matrix (ECM on the diffusion process. At 10 and 20 days, after successful glioma modeling, gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA was introduced into the ECS of rat C6 gliomas. Diffusion parameters and half-life of the reagent were then detected using MRI, and quantified according to the mathematical model of diffusion. The main ECM components [chondroitin sulfate proteoglycans (CSPGs, collagen IV, and tenascin C] were detected by immunohistochemical and immunoblot analyses. In 20-day gliomas, Gd-DTPA diffused more slowly and derived higher tortuosity, with lower clearance rate and longer half-life compared to 10-day gliomas. The increased glioma ECM was associated with different diffusion and clearance parameters in 20-day rat gliomas compared to 10-day gliomas. ECS parameters were altered with C6 glioma progression from increased ECM content. Our study might help better understand the glioma microenvironment and provide benefits for interstitial drug delivery to treat brain gliomas.

  7. Establishment of a Wistar rat model bearing brain glioma C6 cells and its experimental application%Wistar大鼠C6胶质瘤脑移植模型的应用

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    易林华; 傅相平; 李安民; 闫润民

    2011-01-01

    Objective To establish a rat model bearing brain glioma and investigate the optimal conditions for its experimental application. Methods C6 cells were implanted into the unilateral brain hemisphere of 20 Wistar rats. The growth behaviors of the brain tumor and behavioral changes of the rats were observed at different time points after the implantation. Results On day 3 after the implantation, only a slight increase of signal intensity was observed on T2-weighted images. By day 5, the tumor became visible in 15/18 of the rats in at least two sections. By day 11,16/ 18 of the rats showed space-occupying effect in the brain, and by day 14, the tumor occupied over 1/2 of the hemisphere in 14/18 of the rats. By day 20, 14/18 of the rats showed a tumor mass occupying over 2/3 of the hemisphere, and some tumor cells had migrated into the contralateral hemisphere. Conclusion In this model of brain glioma, the optimal time widow for experiment is between 14 and 18 days after the cell implantation. The cell density and viability for implantation and the site of implantation may also affect the experimental time widow.%目的 通过观察C6胶质瘤大鼠脑移植模型,了解该模型的牛物学特点,以帮助实验中有效应用.方法 Wistar大鼠20只,将活性较好的C6胶质瘤细胞微量移植人大鼠大脑半球,观察肿瘤生长特点及行为学改变.结果 肿瘤移植后第3天,TW2即可出现轻微高信号改变.15/18的大鼠在第5天至少能看到2个层面的信号改变.16/18的大鼠在第11天能看见实质性肿瘤.13/18的大鼠第14天生长至半侧大脑的1/2.14/18的大鼠第20大大部分肿瘤达到半侧大脑的2/3,部分生长至对侧半球.结论 实验可能的最佳时间窗在14~18 d.同时,肿瘤移植的初始细胞浓度、细胞活性和移植部位可能也对实验时间窗会有较大影响.

  8. Resection of C6 gliomas in rats with the aid of the waterjet technique.

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    Keiner, Doerthe; Heimann, Axel; Kronfeld, Andrea; Sommer, Clemens; Mueller-Forell, Wibke; Kempski, Oliver; Oertel, Joachim

    2016-07-01

    While clinically the safety and efficacy of waterjet resection of brain tumors have been shown, evidence that waterjet dissection improves tumor resection radicality in comparison with conventional techniques is still missing. In the present study, resection radicality and tumor-free long-term survival of both techniques were evaluated in a C6-glioma model. Fifty-thousand C6-glioma cells were stereotactically transplanted in the left frontal lobe of 100 male Sprague-Dawley rats. After MRI-scanning for evaluation of tumor extension, microsurgical tumor resection was performed with conventional techniques (n=50) or with the waterjet dissector at pressures of 6bar (n=50). Twenty-five animals of each group were sacrificed after surgery for histological analysis. For analysis of survival after tumor resection, twenty-five animals of each group were followed-up to analyze tumor-free survival using the Kaplan Meier method. In the waterjet group, the resection cavity was free of C6-tumor cells in 10/25 (40%) rats showing a trend (p=0.3) towards better resection radicality compared to the rats that were treated conventionally (7/10; 28%). R1-resection with up to 250C6 cells/object slice was found in 14/25 (56%) rats after waterjet dissection compared to 6/25 (24%) rats treated conventionally showing significance (prats. In this experimental model, waterjet tumor resection did reveal significantly better resection radicality compared to the conventional technique. Although a direct transfer of these results to human glioma surgery is prohibited, the waterjet technique might contribute to the best possible resection radicality in human gliomas. Nevertheless, tumor cell spreading remains a major problem. Further studies have to address that the surgical results - in deed - improve the postoperative outcome. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Inhibitory effects of 1-methyl-4-phenylpyridinium on glutamate uptake into cultured C6 glioma cells

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    Hong-hong YAO; Jian-hua DING; Hai-rong HE; Gang HU

    2004-01-01

    To investigate the effect of 1-methyl-4-phenylpyridinium (MPP+) on the glutamate uptake into cultured C6glioma cells. METHODS: The glutamate uptake into C6 glioma cells was measured by radio-ligand binding assay method. The effect of MPP+ on the morphology of C6 glioma cells was observed under phase contrast microscopy;apoptosis of C6 glioma cells were measured by FITC-labeled Annexin V staining and flow cytometry. Cell viability was measured by MTT method. RESULTS: MPP+ inhibited glutamate uptake into C6 glioma cells. However,MPP+ failed to induce any morphological changes of C6 glioma cells, and exposure to MPP+ had no effect on the viability and the apoptotic percentage of C6 glioma cells. Incubation with 12-O-tetradecanoylphorbol -13-acetate (TPA), a protein kinase C activator, caused a significant increase in glutamate uptake and completely reversed MPP+-induced inhibitory effect on glutamate uptake. CONCLUSION: The present results indicate that glutamate transporters may have important pathogenetic implications in Parkinson disease. MPP+-induced inhibition of glutamate uptake was due to the dysfunction of glutamate transporters; TPA enhanced glutamate uptake and completely reversed the inhibitory effect of MPP+.

  10. Estradiol Receptors Regulate Differential Connexin 43 Expression in F98 and C6 Glioma Cell Lines.

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    Zahra Moinfar

    Full Text Available Glioma is the most common malignant primary brain tumour with male preponderance and poor prognosis. Glioma cells express variable amounts of connexin 43 (Cx43 and estrogen receptors (ERs. Both, Cx43 and ERs, play important roles in cell proliferation and migration. Therefore, we investigated the effects of 17-ß estradiol (E2 on Cx43 expression in two glioma cell lines with variable native expression of Cx43.F98 and C6 rat glioma cells were cultured for 24 h in the presence of 10 nM or 100 nM E2, and the E2-antagonist, Fulvestrant. An MTT assay was performed to evaluate cell viability. ERα, ERβ and Cx43 protein expressions were analysed by western blotting and Cx43 mRNA expression was analysed by real-time polymerase chain reaction. To quantify cell migration, an exclusive zone migration assay was used. Functional coupling of cells via gap junctions was examined using whole-cell patch-clamp technique.E2 reduced Cx43 expression in C6 cells, but increased Cx43 expression in F98 cultures. These effects were mediated via ERs. Moreover, E2 promoted C6 cell migration, but it did not affect F98 cell migration. The expression level of ERα was found to be high in C6, but low in F98 cells. ERβ was exclusively expressed in C6 cells. In addition, E2 treatment induced a significant decrease of ERβ in C6 cultures, while it decreased ERα expression in F98 glioma cells.These findings show that E2 differentially modulates Cx43 expression in F98 and C6 glioma cells, likely due to the differential expression of ERs in each of these cell lines. Our findings point to the molecular mechanisms that might contribute to the gender-specific differences in the malignancy of glioma and could have implications for therapeutic strategies against glioma.

  11. Applying stereotactic technique to establish C6 brain glioma models for laser interstitial thermotherapy research%立体定向技术建立大鼠脑胶质瘤激光间质热疗模型

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    石键; 张宏; 卜文良; 陈鹏; 赵洪洋; 傅伟明

    2010-01-01

    Objective C6 brain glioma models were established with stereotactic technique to study laser interstitial thermotherapy (LITT) in SD rats C6 intracranial glioma models. Methods The C6 cells cultured in vitro were stereotaxically implanted into the right caudate nucleus of SD rat brain (20 μl free serum DMEM for one rat which concentration was 1×10~(11)/L). The following step was to judge MRI scan. Tumor was confirmed with staining of ⅧR, GFAP and S - 100 immunohistochemistry. After MRI scanning and correction of tumor location, the models were divided into groups according treating time and laser power from 2 to 10 W. Semiconductor laser optical fibers were inserted in tumors for LITT, simultaneously cortex's temperature conducted from center target was measured by ThermaCAM S65 type infrared thermograph, and (or) deep tissue's temperature around target was measured by thermocouple. Results Inoculated with optimized stereotactic technique, rat C6 gliomas resembled histopathological features of human glioma. This kind of model was a more reliant and reproducible one, with 96. 67% yield of intracranial tumor as well as no extracranial growth extension. The difference between cortex temperature conducted from center target and deep tissue temperature around target had no statistical significance (P>0.05). Conclusion A rat C6 brain glioma model resembles histopathological features of human glioma, as a perfect model to study LITT of glioma. Infrared thermograph technique to measure temperature conveniently, effectually, non invasive and the data could be treated by software in LITT research. Combining thermocouple to measure deep tissue temperature, it would have a better effect.%目的 利用立体定向技术接种SD大鼠C6脑胶质瘤,并建立脑胶质瘤激光间质热疗(LITT)模型.方法 采用立体定向技术,将体外培养并调制的C6胶质瘤细胞悬液20μl(浓度1×10~(11)/L)接种于SD大鼠右侧尾状核区.分时段MRI检查;做组织病理

  12. Increasing of Blood-Brain Tumor Barrier Permeability through Transcellular and Paracellular Pathways by Microbubble-Enhanced Diagnostic Ultrasound in a C6 Glioma Model

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    Zhang, Jinlong; Liu, Heng; Du, Xuesong; Guo, Yu; Chen, Xiao; Wang, Shunan; Fang, Jingqin; Cao, Peng; Zhang, Bo; Liu, Zheng; Zhang, Weiguo

    2017-01-01

    Most of the anticancer agents cannot be efficiently delivered into the brain tumor because of the existence of blood-brain tumor barrier (BTB). The objective of this study was to explore the effect of microbubble-enhanced diagnostic ultrasound (MEUS) on the BTB permeability and the possible mechanism. Glioma-bearing rats were randomized into three groups as follows: the microbubble-enhanced continued diagnostic ultrasound (MECUS) group; the microbubble-enhanced intermittent diagnostic ultrasound (MEIUS) group and the control group. The gliomas were insonicated through the skull with a diagnostic ultrasound and injected with microbubbles through the tail veins. Evans Blue (EB) and dynamic contrast-enhanced-MRI were used to test changes in the BTB permeability. Confocal laser scanning microscopy was used to observe the deposition of the EB in the tumor tissues. The distribution and expression of junctional adhesion molecule-A (JAM-A) and calcium-activated potassium channels (KCa channels) were detected by a Western blot, qRT-PCR, and immunohistochemical staining. In the MEUS groups, the EB extravasation (11.0 ± 2.2 μg/g in MECUS group and 17.9 ± 2.3 μg/g in MEIUS group) exhibited a significant increase compared with the control group (5.3 ± 0.9 μg/g). The MEIUS group had more EB extravasation than the MECUS group. The Ktrans value of the dynamic contrast-enhanced-MRI in the MEUS groups was higher than that of the control group and correlated strongly with the EB extravasation in the tumor (R2 = 0.97). This showed that the Ktrans value might be a non-invasive method to evaluate the BTB permeability in rat glioma after microbubble-enhanced ultrasound treatment.Western blot, qRT-PCR and immunohistochemical staining revealed that MEUS increased the KCa channels expression and reduced JAM-A expression in glioma. This change was more obvious in the MEIUS group than in the MECUS group. The results demonstrated that MEUS effectively increased the BTB permeability in

  13. p38MAPK gene transfection induced the apoptosis of rat glioma cells C6

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    ZHANG Bi-cheng; LI Qing; YE Jing; WANG Ying-mei; LIN Sheng-cai

    2001-01-01

    To study the effect ofp38MAPK transfecfion on the biological characteristics of rat glioma cells C6. Methods: p38MAPK was transfected into C6 cells by lipofectin. Expression ofp38MAPK in C6 cells before and after transfection was detected by immunocytochemistry and Western-blot analysis. HE staining,transmission electron microscopy and flow cytometry were used to observe the cell morphology, adhesion and study the cell cycle. Results: p38MAPK expressed in C6 cells after transfection. Cell biological characteristics changed,and apoptotic cells emerged. Conclusion: Exogenous p38MAPK could induce the apoptosis of C6 cells.

  14. Cisplatin treatment of C6 rat glioma in vivo did not influence copy number alterations and growth pattern of tumor-derived resistant cells

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    Stepanenko A. A.

    2015-06-01

    Full Text Available Aim. To investigate whether the cisplatin treatment of C6 rat glioma in vivo impacts the copy number alterations (CNAs, proliferation and colony formation efficiency (CFE of tumor-derived cisplatin-resistant cells. Methods. The glioma modeling was performed by means of intracerebral stereotactic implantation of rat glioma C6 cells into the striatum region of rats. The rats received 20 % dimethyl sulfoxide DMSO (C6R1 or cisplatin (C6R4CIS and C6R5CIS injected intraperitoneally (5 mg/kg three times per week. After 10 injections, gliomas were resected and the cells were cultured for in vitro analysis. CNAs were analyzed by array comparative genome hybridization, proliferation by direct cell counting in hemocytometer, CFE by soft agar assay. Results. No significant changes in the CNAs and CFE of cisplatin-treated rat glioma C6R4CIS and C6R5CIS cell lines were observed compared to the vehicle-treated control C6R1 cells. However, C6R5CIS but not C6R4CIS had a reduced proliferation. Interestingly, both cisplatin- and vehicle-treated brain-grown cells had a reduced proliferation and CFE in comparison to the parental C6 cells. Conclusions. Despite numerous reports on the destabilizing effects of cisplatin on genome and phenotype, the cisplatin treatment of C6 cells in vivo did not affect genome stability, CFE, and had an inconsistent effect on the proliferation in vitro. The rat brain microenvironment may potentially impact the growth characteristics of rat glioma cells.

  15. Induction of apoptosis and inhibition of proliferation of C6 glioma cells in vitro by tamoxifen

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    2007-01-01

    Objective To investigate the anti-tumor effect and mechanism of tamoxifen on rat C6 glioma cells. Methods C6 cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with 3% fetal calf serum (FCS), and treated with tamoxifen of different concentrations, i.e. group A (1.25μmol/L), group B (2.50 μmol/L), group C (5.00 μmol/L), group D (10.00 μmol/L), group E (20.00 μmol/L) and control group (0.00 μmol/L). Morphological changes, MTT assay and 5-bromo-2'-deoxyuriding labeling ratio were assessed. Apoptosis was observed by flow cytometry. Results C6 cells treated with different doses of tamoxifen for 24, 48, and 72 hours became irregular in shape, while cells treated with vehicle grew normally. MTT assay showed that tamoxifen did not suppress C6 cell growth until 72 hours after treatment. Seventy-two hours after treatment, there were significant differences in cell viable rate between group A versus groups C, D and E; so did group B versus group D as well as group E (P<0.05). BrdU incorporation assay indicated significant difference of BrdU labbled index (BrdU LI) among groups A, C, E and control group 48 hours after treatment (P<0.05). And the BrdU LI decreased with the increased concentration of tamoxifen. Flow cytometry (FCM) showed significant difference between treated group and control group at 24, 48, and 72 hours after treatment (P<0.05). Conclusion Tamoxifen significantly suppresses the growth of C6 glioma cells in a time- and dose-dependent manner. The mechanism of tamoxifen suppressing C6 glioma cells may be inhibiting proliferation and inducing apoptosis. Therefore, tamoxifen can be a candidate as a chemotherapy agent for glioma.

  16. Proteasome inhibitor MG-132 induces C6 glioma cell apoptosis via oxidative stress

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    Wen-hai FAN; Yi HOU; Fan-kai MENG; Xiao-fei WANG; Yi-nan LUO; Peng-fei GE

    2011-01-01

    Aim: Proteasome inhibitors have been found to suppress gtioma cell proliferation and induce apoptosis, but the mechanisms are not fully elucidated. In this study we investigated the mechanisms underlying the apoptosis induced by the proteasome inhibitor MG-132 in glioma cells.Methods: C6 glioma cells were used. MTF assay was used to analyze cell proliferation. Proteasome activity was assayed using Succi-nyI-LLVY-AMC, and intracellular ROS level was evaluated with the redox-sensitive dye DCFH-DA. Apoptosis was detected using fluores-cence and transmission electron microscopy as well as flow cytometry. The expression of apoptosis-related proteins was investigated using Western blot analysis.Results: MG-132 inhibited C6 glioma cell proliferation in a time- and dose-dependent manner (the IC value at 24 h was 18.5 μmol/L). MG-132 (18.5 μmol/L) suppressed the proteasome activity by about 70% at 3 h. It induced apoptosis via down-regulation of antiapop-totic proteins Bcl-2 and XlAP0 up-regulation of pro-apoptotic protein Bax and caspase-3, and production of cleaved C-terminal 85 kDa PARP). It also caused a more than 5-fold increase of reactive oxygen species. Tiron (1 mmol/L) effectively blocked oxidative stress induced by MG-132 (18.5 pmol/L), attenuated proliferation inhibition and apoptosis in C6 glioma cells, and reversed the expression pattern of apoptosis-related proteins.Conclusion: MG-132 induced apoptosis of C6 glioma cells via the oxidative stress.

  17. Uptake and Toxicity of Copper Oxide Nanoparticles in C6 Glioma Cells.

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    Joshi, Arundhati; Rastedt, Wiebke; Faber, Kathrin; Schultz, Aaron G; Bulcke, Felix; Dringen, Ralf

    2016-11-01

    Copper oxide nanoparticles (CuO-NPs) are frequently used for many technical applications, but are also known for their cell toxic potential. In order to investigate a potential use of CuO-NPs as a therapeutic drug for glioma treatment, we have investigated the consequences of an application of CuO-NPs on the cellular copper content and cell viability of C6 glioma cells. CuO-NPs were synthesized by a wet-chemical method and were coated with dimercaptosuccinic acid and bovine serum albumin to improve colloidal stability in physiological media. Application of these protein-coated nanoparticles (pCuO-NPs) to C6 cells caused a strong time-, concentration- and temperature-dependent copper accumulation and severe cell death. The observed loss in cellular MTT-reduction capacity, the loss in cellular LDH activity and the increase in the number of propidium iodide-positive cells correlated well with the specific cellular copper content. C6 glioma cells were less vulnerable to pCuO-NPs compared to primary astrocytes and toxicity of pCuO-NPs to C6 cells was only observed for incubation conditions that increased specific cellular copper contents above 20 nmol copper per mg protein. Both cellular copper accumulation as well as the pCuO-NP-induced toxicity in C6 cells were prevented by application of copper chelators, but not by endocytosis inhibitors, suggesting that liberation of copper ions from the pCuO-NPs is the first step leading to the observed toxicity of pCuO-NP-treated glioma cells.

  18. Delta9-tetrahydrocannabinol stimulates glucose utilization in C6 glioma cells.

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    Sánchez, C; Velasco, G; Guzmán, M

    1997-08-29

    The present work was undertaken to study the metabolic response of C6 glioma cells to physiologically relevant doses of delta9-tetrahydrocannabinol (THC), the major active component of marijuana. At those concentrations (i.e. nanomolar range), THC produced a dose-dependent increase in the rates of glucose oxidation to CO2 and glucose incorporation into phospholipids and glycogen. The THC-induced stimulation of glucose utilization was (i) dose-dependent up to 100 nM THC, (ii) mimicked by the synthetic cannabinoid HU-210, and (iii) prevented by pertussis toxin and the CB1 receptor antagonist SR141716A. In contrast to THC, forskolin markedly depressed CO2 production, phospholipid synthesis and glycogen synthesis from glucose. The forskolin-induced inhibition of glucose utilization was (i) mimicked by dibutyryl-cAMP, and (ii) prevented by THC, HU-210 and H-7, an inhibitor of the cAMP-dependent protein kinase. Likewise, THC was able to antagonize in part the forskolin-induced elevation of intracellular cAMP concentration, and this antagonistic effect was prevented by SR141716A. However, THC per se did not affect basal cAMP concentration. Results thus indicate that physiologically relevant doses of THC stimulate glucose metabolism in C6 glioma cells through a cannabinoid receptor-mediated process. Although cannabinoid receptors may be coupled to inhibition of adenylyl cyclase in C6 glioma cells, this does not seem to be the mechanism involved in the THC-induced stimulation of glucose metabolism.

  19. Lithium chloride decreases proliferation and migration of C6 glioma cells harboring isocitrate dehydrogenase 2 mutant via GSK-3β.

    Science.gov (United States)

    Fu, Yuejun; Zheng, Yali; Chan, Kok-Gan; Liang, Aihua; Hu, Fengyun

    2014-06-01

    The gene encoding isocitrate dehydrogenase (IDH) is somatically mutated predominantly in secondary glioblastoma multiforme. Mutations of IDH1 and IDH2 lead to simultaneous loss and gain of activities in the production of α-ketoglutarate and 2-hydroxyglutarate, respectively. Lithium chloride was recently proved efficient in inhibiting glioma cell migration. The mechanism of lithium chloride on C6 glioma cells harboring IDH2 mutation has not been studied. Here, we found lithium chloride induced inhibitive effects on cell proliferation of both C6 glioma cells with and without IDH2 mutation, although IDH2 mutation increased the stability of HIF-1α. GSK-3β could be phosphorylated at Ser9 and its activity was inhibited when C6 glioma cells were treated by lithium chloride. The degree of phosphorylation in IDH2(R172G) treatment group was lower than that as compared to the control and IDH2 treatment groups. At the same time, the accumulation of β-catenin in C6 cell nucleus was decreased. Moreover, although the β-catenin and HIF-1α increased the secretion of metalloproteinase-2,-9 in C6 glioma cells harboring IDH2 mutation, the migration potential of lithium chloride-treated C6 glioma cells harboring the IDH2 and its mutant was uniform. These results indicated lithium chloride could decrease the proliferation and migration potential of C6 glioma cells harboring IDH2 mutation.

  20. Trypsin promotes C6 glioma cell proliferation in serum- and growth factor-free medium.

    Science.gov (United States)

    Amano, H; Kurosaka, R; Ema, M; Ogawa, Y

    1996-07-01

    C6 glioma cells could be successively subcultured and maintained in serum- and growth factor-free medium (SF/GFF medium). C6 cell proliferation in SF/GFF medium was positively correlated with the initial cell density at plating. This correlation disappeared when the medium had been renewed early after cell adhesion (3 h after plating), suggesting that C6 cell growth depends on some diffusible factor in the medium before renewal, and that this factor is not secreted from C6 cells in the assay culture but is transferred from the cell suspension. The supernatant of trypsinized C6 cell suspension (SCS), trypsin-EDTA solution for routine cell harvesting use, and modified trypsin of protein sequencing grade all promoted C6 cell proliferation at, appropriate dilutions or concentrations under SF/GFF conditions. The growth promoting effects of SCS and trypsin-EDTA solution were completely inhibited by soybean trypsin inhibitor. These results demonstrate that the serine protease trypsin has a proliferative effect on C6 cells continuously subcultured in SF/GFF medium. In addition, it is suggested that trypsin used for cell dispersion is transferred from cell suspension into the culture, where it promotes C6 cell growth after passage in our SF/GFF subculture system.

  1. β-diketone-cobalt complexes inhibit DNA synthesis and induce S-phase arrest in rat C6 glioma cells

    OpenAIRE

    ZHANG, KAIZHI; Zhao, Xingli; Liu, Junzhi; FANG, XIANGYANG; Wang, Xuepeng; Wang, Xiaohong; Li, Rui

    2013-01-01

    β-diketone-cobalt complexes, a family of newly synthesized non-platinum metal compounds, exhibit potential antitumor activity; however, the antitumor mechanism is unclear. The current study investigated the mechanism by which β-diketone-cobalt complexes inhibit rat C6 glioma cell proliferation. It was found that β-diketone-cobalt complexes suppress rat C6 glioma cell viability in a dose-dependent manner (3.125–100 μg/ml). In rat C6 glioma cells, the IC50 value of β-diketone-cobalt complexes w...

  2. Dopamine induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages in rat C6 glioma

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Tian; Wang, Chenlong; Chen, Xuewei; Duan, Chenfan; Zhang, Xiaoyan [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Zhang, Jing [Animal Experimental Center of Wuhan University, Wuhan 430071 (China); Chai, Hongyan [Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan 430071 (China); Tang, Tian [Department of Oncology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Chen, Honglei [Department of Pathology and Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Yue, Jiang [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Li, Ying, E-mail: lyying0@163.com [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Yang, Jing, E-mail: yangjingliu2013@163.com [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China)

    2015-07-15

    Dopamine (DA), a monoamine catecholamine neurotransmitter with antiangiogenic activity, stabilizes tumor vessels in colon, prostate and ovarian cancers, thus increases chemotherapeutic efficacy. Here, in the rat C6 glioma models, we investigated the vascular normalization effects of DA and its mechanisms of action. DA (25, 50 mg/kg) inhibited tumor growth, while a precursor of DA (levodopa) prolonged the survival time of rats bearing orthotopic C6 glioma. DA improved tumor perfusion, with significant effects from day 3, and a higher level at days 5 to 7. In addition, DA decreased microvessel density and hypoxia-inducible factor-1α expression in tumor tissues, while increasing the coverage of pericyte. Conversely, an antagonist of dopamine receptor 2 (DR2) (eticlopride) but not DR1 (butaclamol) abrogated DA-induced tumor regression and vascular normalization. Furthermore, DA improved the delivery and efficacy of temozolomide therapy. Importantly, DA increased representative M1 markers (iNOS, CXCL9, etc.), while decreasing M2 markers (CD206, arginase-1, etc.). Depletion of macrophages by clodronate or zoledronic acid attenuated the effects of DA. Notably, DA treatment induced M2-to-M1 polarization in RAW264.7 cells and mouse peritoneal macrophages, and enhanced the migration of pericyte-like cells (10T1/2), which was reversed by eticlopride or DR2-siRNA. Such changes were accompanied by the downregulation of VEGF/VEGFR2 signaling. In summary, DA induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages. Thus, targeting the tumor microvasculature by DA represents a promising strategy for human glioma therapy. - Highlights: • Dopamine induces tumor growth inhibition and vascular normalization in rat C6 glioma. • Dopamine switches macrophage phenotype from M2 to M1. • Dopamine-induced vascular normalization is mediated by macrophage polarization. • Dopamine is a promising agent targeting the microvasculature in tumor

  3. Anticancer and antiangiogenic effects of methanol extracts of Lonicera caprifolium L. on C6 rat glioma cells

    Directory of Open Access Journals (Sweden)

    Nergiz Hacer Turgut

    2016-03-01

    Full Text Available Objective: Gliomas are brain tumors with high morbidity and mortality. For the treatment of gliomas, it is important to develop new and powerful treatments that could complement existing clinical treatment. Lonicera caprifolium L. (L. caprifolium has various uses in herbal traditional medicine. This study was conducted to determine the phenolic acid levels and DNA damage protection potential of L. caprifolium extract, and to explore the antitumor effect of the extract by investigating its toxicity on C6 rat glioma cell lines and normal L929 mouse fibroblast cell lines. We also aimed to investigate the antiangiogenic potential of the extract. Method: Phenolic acid content was determined by HPLC analysis. DNA damage protection potential was evaluated on pBR322 plasmid DNA. The effect of extracts on the proliferation of cancer cells was evaluated by XTT assay. Antiangiogenic effect was determined with Chorioallantoic membrane model. Results: The extract was found rich in vanillic acid (273.003 µg/g; while the amount of chlorogenic acid was almost at negligible level (0.028 µg/g. 0.005-0.05 mg / ml extract protected against the hazardous effects of UV and H2O2 in all DNA bands. The presence of the extract significantly reduced C6 cell proliferation compared to control (p<0.05. The extract had antiproliferative effect with a half maximum inhibition of concentration (IC50 value of 0.45 mg/ml. L. caprifolium extract in 10-6, 10-5 and 10-4 M concentrations caused antiangiogenic effect. Antiangiogenic scores of L. caprifolium were 0.6, 0.73 and 1.6, respectively. Conclusions: These results show that L. caprifolium has potential cytotoxic and antiangiogenic effect on C6 rat glioma cells and that the phenolic acid content of the plant may partially influence these activities.

  4. Wuweizisu C from Schisandra chinensis decreases membrane potential in C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Young-whan CHOI; Kyeok KIM; Ji-yeong JO; Hyo-lim KIM; You-jin LEE; Woo-jung SHIN; Santosh J SACKET; Mijin HAN; Dong-soon IM

    2008-01-01

    Aim:To study the effects of dibenzocyclooctadiene lignans isolated from Schi-sandra chinensis, such as wuweizisu C, gomisin N, gomisin A, and schisandrin, on the membrane potential in C6 glioma cells. Methods: The membrane po-tential was estimated by measuring the fluorescence change in DiBAC-loaded glioma cells. Results: Wuweizisu C decreased the membrane potential in a concentration-dependent manner. Gomisin N and gomisin A, however, showed differential modulation and no change was induced by schisandrin or dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylene dioxybiphenyl-2,2'-dicarboxylate, a syn-thetic drug derived from dibenzocyclooctadiene lignans. We found no involve-ment of Gi/o proteins, phospholipase C, and extracellular Na+ on the wuweizisu C-indueed decrease of the membrane potential. Wuweizisu C by itself did not change the intracellular Ca2+ [Ca2+]I concentration, but decreased the ATP-indu-ted Ca2+ increase in C6 glioma cells. The 4 lignans at all concentrations used in this study did not induce any effect on cell viability. Furthermore, we found a similar decrease of the membrane potential by wuweizisu C in PC12 neuronal cells. Conclusion: Our results suggest that the decrease in the membrane poten-tial and the modulation of [Ca2+]I concentration by wuweizisu C could be impor-tant action mechanisms ofwuweizisu C.

  5. Interstitial Chemotherpy with doxorubicin-loaded PLA polymer for S.C. C6 glioma model in rats and examining PLA-doxorubicin controlled-release capacity with HPLC

    Institute of Scientific and Technical Information of China (English)

    WANG Qin; LI Bao-lu; ZHANG Ming-chen; LI Xin-gang; HAO Xiao-guang

    2001-01-01

    @@ Glioma has the highest incidence in the brain tumors. Though treated with surgical resection, external beam radiation therapy, and systemic chemotherapy, patients with glioma have poor prognosis because of glioma recurrence.

  6. Construction of rat glioma cell line C6-Luc for reproducing an animal model with stable expression of luciferase%大鼠脑胶质瘤荧光素酶动物模型建模细胞株C6-Luc的构建

    Institute of Scientific and Technical Information of China (English)

    黄伟; 吕明; 李保卫; 王玉丽; 邵荣光; 高钟镐

    2011-01-01

    Objective To construct the rat glioma cell line C6-Luc to stably express the firefly luciferase.Methods The optimal concentration of hygromycin for screening C6 rat glioma cells was determined by concentration gradient method.The eukaryotic plasmid pGL4.50 expressing luciferase was transfected into C6 cells by using FuGENE* HD transfection reagent, followed by screening the polyclonal cell lines with hygromycin, subsequently screening the monoclonal cell line by limited dilution.The positive monoclonal cell lines were identified with reporter gene assay, thereafter the expression stability of luciferase was investigated in the positive cell lines.The bioluminescence detection in vitro in the positive monoclonal cell line was performed to determine the minimum detection amount of cells,and the correlation between bioluminescence intensity and ce11 amount was analyzed by linear regression analysis.The positive monoclonal cells were implanted into the brain of Wistar rats, and the tumor growth in rats brain was detected in vivo using the bioluminescence imaging detection system.Results The optimal concentration of hygromycin used in screening C6 cells was 250 μg/mL The eukaryotic plasmids pGL4.50 was successfully transfected into C6 cells, and 12 monoclonal cell lines were obtained by anti-hygromycin screening.A positive clone with the highest activity of luciferase, designated as C6-Luc, was successfully identified by using luciferase reporter gene assay, which showed a stable activity of expressing luciferase after 3 continuous passages of cultivation.The bioluminescence detection in vitro showed that the minimum detection amount of C6-Luc cells was 78.A good linear correlation existed between bioluminescence intensity and the amount of C6-Luc cells, with an equation of y=81.348x-2143.1 and correlation coefficient(r) of 0.997.The in vivo bioluminescence imaging detection showed tumorigenesis could be detected after implantation of C6-Luc cells into the brain of

  7. Biodegradable microfibers deliver the antitumor drug temozolomide to glioma C6 cells in vitro.

    Science.gov (United States)

    Fan, Xiaoyong; Ni, Shilei; Qi, Hongxu; Wang, Xuping; Wang, Chuanwei; Liu, Yuguang

    2010-11-01

    To develop effective implants for delivery of 3,4-dihydro-3-methyl-4-oxoimidazo[5,1-d]-as-tetrazine-8-carboxamide (temozolomide; TM) with low initial burst and less neurotoxicity, TM-loaded poly-propylene carbonate (PPC) fiber was fabricated by electrospinning. Some of the fiber sheets were then covered with alginate (ALG). Influences of several preparation parameters on drug delivery behavior were investigated. The micro-morphology of these fibers was studied using scanning electron microscopy and differential scanning calorimetry. In vitro release properties of two forms of samples were observed and their cytotoxicity against C6 glioma cells was assessed. Using strict preparation parameters, smooth and uniform fiber could only be obtained when the PPC concentration was 8 % by weight, at 20cm and a voltage of 15 kV between the nozzle and the collection instrument. Fiber diameter was about 3 microm. The initial burst of drug-fiber sheets was reduced after the fiber sheets were covered with ALG. Cytotoxicity test results suggested that both forms of drug fibers inhibit the C6 glioma cells continuously; the pure drug-fiber sheets were strongly cytotoxic. We conclude that (a) electrospinning is a reliable fabrication method for M-loaded PPC fibers; and (b) an ALG coating reduces the initial burst of the fiber sheets.

  8. Cellular antioxidant adaptive survival response to 6-hydroxydopamine-induced nitrosative cell death in C6 glioma cells.

    Science.gov (United States)

    Lee, Chan; Park, Gyu Hwan; Jang, Jung-Hee

    2011-05-10

    Parkinson's disease (PD) is a progressive neurodegenerative movement disorder characterized by selective loss of dopaminergic neurons in the substantia nigra. 6-Hydroxydopamine (6-OHDA) is a catecholaminergic neurotoxin widely used to produce experimental models of PD and has been reported to cause oxidative and/or nitrosative stress. In this study, we have investigated 6-OHDA-induced nitrosative cell death and its self-defense mechanism in C6 glioma cells. Treatment of C6 cells with 6-OHDA increased expression of inducible nitric oxide synthase (iNOS) and subsequent production of nitric oxide (NO). Furthermore 6-OHDA treatment led to peroxynitrite generation and nitrotyrosine formation. 6-OHDA-induced nitrosative stress ultimately caused apoptotic cell death as determined by decreased Bcl-2/Bax ratio, activation of c-Jun N-terminal kinase (JNK), and cleavage of caspase-3 and poly(ADP-ribose)polymerase (PARP), which were attenuated by peroxynitrite decomposition catalyst, 5,10,15,20-tetrakis(4-sulfonatophenyl)prophyrinato iron(III) (FeTPPS). In another experiment, exposure of C6 glioma cells to 6-OHDA resulted in an increased expression of heme oxygenase-1 (HO-1) and 6-OHDA-induced cytotoxicity was effectively suppressed by the HO-1 inducer SnCl(2) and aggravated by HO-1 inhibitor zinc protoporphyrin (ZnPP), supporting the cytoprotective role of HO-1. To elucidate the molecular mechanism underlying 6-OHDA-mediated HO-1 induction, we have examined the possible involvement of NF-E2-related factor 2 (Nrf2), which plays an important role in the transcriptional regulation of phase II detoxifying and antioxidant enzymes. 6-OHDA treatment increased nuclear translocation and transcriptional activity of Nrf2, which seemed to be partly mediated by activation of upstream kinases such as Akt/protein kinase B (PKB). Taken together these findings suggest that HO-1 up-regulation via Nrf2 activation may mediate the cellular adaptive survival response to 6-OHDA-induced nitrosative

  9. Effects of antigliomatin from the scorpion venom of Buthus martensii Karsch on chloride channels on C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Zan Wang; Mingxian Li; Hongmei Meng; Min Huang; Weihong Lin; Li Cui; Shao Wang

    2011-01-01

    Using whole-cell patch-clamp recordings, the effects of antigliomatin were observed on chloride channels on C6 glioma cells cultured in vitro. Antigliomatin was extracted from the venom of the scorpion Buthus martensii Karsch. Chloride channels are closed under normal osmotic pressure. When osmotic pressure was reduced to 120, 110 and 100 mV, the cell volume enlarged, chloride channels opened, and the chloride channel current increased. Three minutes after antigliomatin treatment, the chloride channel current decreased in a dose-dependent manner. These results show that antigliomatin extracted from the venom of the scorpion Buthus martensii Karsch diminishes chloride channel currents on C6 glioma cells.

  10. Stable EGFP Gene Expression in C6 Glioma Cell Line after Transduction with HIV-1-based Lentiviral Vector

    Institute of Scientific and Technical Information of China (English)

    JIN Gui-shan; LIU Fu-sheng; CHAI Qi; WANG Jian-jao; LI Jun-hua

    2008-01-01

    Objective:To establish a stable C6/EGFP glioma cell line for studies on glioma. Methods:The C6 glioma cell line was transfected with the human immunodeficiency virus type Ⅰ(HIV-1)based lentivirus vector containing two enhancer-promoters CMV and EF1α.Enhanced green fluorescent protein(EGFP)-positive C6 cells were sorted out by fluorescence-activated cell sort.Expression of EGFP was observed by fluorescent microscopy.EGFP gene in C6 genome was assessed by Polymerase chain reaction(PCR)and DNA sequencing.Original and transfected cells were compared biologically and cytomorphologically. Results:Lentivirus vector transfection produced up to 40% EGFP-positive cells.After fluorescence-activated cell sort selection,a pure cell line C6/EGFP was established.PCR and DNA sequencing revealed integration of EGFP gene in C6 cell genome.Analysis of cell characteristics revealed no difference between transfected and original cells. Conclusion:A C6/EGFP cell line expressing EGFP as a marker is established,in which the EGFP gene is integrated into the genome.This cell line can be served as a promising tool for further basic research and gene therapy studies.

  11. β-diketone-cobalt complexes inhibit DNA synthesis and induce S-phase arrest in rat C6 glioma cells.

    Science.gov (United States)

    Zhang, Kaizhi; Zhao, Xingli; Liu, Junzhi; Fang, Xiangyang; Wang, Xuepeng; Wang, Xiaohong; Li, Rui

    2014-03-01

    β-diketone-cobalt complexes, a family of newly synthesized non-platinum metal compounds, exhibit potential antitumor activity; however, the antitumor mechanism is unclear. The current study investigated the mechanism by which β-diketone-cobalt complexes inhibit rat C6 glioma cell proliferation. It was found that β-diketone-cobalt complexes suppress rat C6 glioma cell viability in a dose-dependent manner (3.125-100 μg/ml). In rat C6 glioma cells, the IC50 value of β-diketone-cobalt complexes was 24.7±3.395 μg/ml and the IC10 value was 4.37±1.53 μg/ml, indicating a strong inhibitory effect. Further investigation suggested that β-diketone-cobalt complexes inhibit rat C6 glioma cell proliferation, which is associated with S-phase arrest and DNA synthesis inhibition. During this process, β-diketone-cobalt complexes decreased cyclin A expression and increased cyclin E and p21 expression. In addition, β-diketone-cobalt complexes exhibit a stronger antitumor capability than the antineoplastic agent, 5-fluorouracil.

  12. Curcumin delivery by methoxy polyethylene glycol-poly(caprolactone) nanoparticles inhibits the growth of C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Junfei Shao; Donghui Zheng; Zhifeng Jiang; Huae Xu; Yong Hu; Xiaolin Li; Xiaowei Lu

    2011-01-01

    As a potential anticancer agent, curcumin (Cum) has been reported for its chemopreventive and chemotherapeutic activity in a series of cancers through influencing cell cycle arrest, differentiation, apoptosis, etc. Therefore, the potential activity against various cancers of Cure raises the possibility of its application as a novel model drug in nanopartiele-based delivery systems. The current study reported a spherical core-shell structure curcumin-loaded nanoparticle (Cum-np) formed by amphllic methoxy polyethylene glycolpoly(caprolactone) (mPEG-PCL) block copolymers. Characterization tests indicated that Cum was incorporated into mPEG-PCL-based nanoparticles with high encapsulation efficiency due to its lipophilicity. The incorporated Cum could be released from Cum-np in a sustained manner. Cum was effectively transported into the cells by nanoparticles through endocytosis and localized around the nuclei in the cytoplasms. In vitro studies proved that the cytotoxicity of Cum-np would be pro-apoptosis effect against rat C6 glioma cell line in a dose-dependent manner. The present results suggest that Cum-np could be a potential useful chemotherapeutic formulation for malignant glioma therapy. Moreover, the development of traditional Chinese medicine with nanoscale drug formation warrants more intensive research for its clinical applications.

  13. Investigating effect of fusion gene therapy by MR diffusion-weighted imaging in a rat C6 glioma model%融合基因治疗大鼠C6胶质瘤的MR扩散加权成像研究

    Institute of Scientific and Technical Information of China (English)

    沈慧聪; 赵炜疆; 高培毅; 戴建平; 魏新华; 王建交; 李少武; 马军; 艾林; 刘福生; 柴奇

    2008-01-01

    Objective To evaluate the use of diffusion-weighted imaging(DWI)for early detection of tumor response to Angiostatin-Endostatin(Statin-AE)fusion gene therapy in a rat C6 glioma model.Methods Fifty male wistar rats with C6 tumor cells implanted into the striatum were examined by a 3.0T MR scanner,then the rats beating tmors were divided into two groups,treatment group and control group.Rats in the treatment group received 107 plaque forming unit(pfu)recombinant herps simplex viral (R-HSV)mediated Statin-AE fusion gene therapy on day 7,and then the tumors were conformed on MRI.Conventional MR and DWI examination were acquired on 1,2,3 weeks after implantation with a 5-inch surface coil.Two(1 w),eight(2 w)and all the residual rats(3 w)of each group were sacrificed to perform the histopathological examination after each MBI examination.Pretreatment and post treatment tumor volulnes and apparent diffusion coefficient(ADC)values were calculated.Rank sum test and t test were employed for statistical analysis.Results On MRI,43 rats demonstrated tumors on day 7 with a successful rate of 86%,On week 2,the tumor volumes of the controh and treatment group were 90.6 and 91.64 mm3,with no significant difference(Z=-0.14,P>0.05).On week 3,the tumor volumes of the controls and treatment group were 156.64 and 29.64 mm3,and a significant difference was observed(Z=-3.45,P<0.01).On week 2.the ADC values of the tumor centers of the treatment group and the control group were (1.20±0.25)×10-3 and(0.99±0.08)×10-3 mm2/s,and the values of the tumor peripheral parts of the two groups were(1.00±0.25)×10-3 and(0.83±0.12)×10-3mm2/s,the ADC values of both tumor centers and peripheral parts of the treatment group were significantly higher than those of the control group (t=-0.82 and-0.46,P<0.05).On week 3,the ADC values of the tumor centers of the treatment group and the control group were(0.92±0.21)× 10-3 and(0.99±0.09)×10-3mm2/s,and the values of the tumor peripheral parts of

  14. Hydrophobic fractal surface from glycerol tripalmitate and the effects on C6 glioma cell growth.

    Science.gov (United States)

    Zhang, Shanshan; Chen, Xuerui; Yu, Jing; Hong, Biyuan; Lei, Qunfang; Fang, Wenjun

    2016-06-01

    To provide a biomimic environment for glial cell culture, glycerol tripalmitate (PPP) has been used as a raw material to prepare fractal surfaces with different degrees of hydrophobicity. The spontaneous formation of the hydrophobic fractal surfaces was monitored by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The surface morphologies were observed by a scanning electron microscope (SEM), and then the fractal dimension (FD) values of the surfaces were determined with the box-counting method. C6 glioma cells were cultured and compared on different hydrophobic PPP surfaces and poly-L-lysine (PLL)-coated surface. The cell numbers as a function of incubation time on different surfaces during the cell proliferation process were measured, and the cell morphologies were observed under a fluorescence microscope. Influences of hydrophobic fractal surfaces on the cell number and morphology were analyzed. The experimental results show that the cell proliferation rates decrease while the cell morphology complexities increase with the growth of the fractal dimensions of the PPP surfaces.

  15. Underlying mechanism of ASIC1a involved in acidosis-induced cytotoxicity in rat C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Xie-chuan WENG; Jian-quan ZHENG; Jin LI; Wen-bin XIAO

    2007-01-01

    Aim:To investigate the underlying mechanism of acid-sensing ion channel (ASIC) la involved in the acidosis-induced cytotoxicity of rat C6 glioma cells. Methods:The stable ASICla-silenced C6 cells built with the RNA interference technology were confirmed by RT-PCR and Western blot analysis. Intracellular calcium ([Ca2+]i) in both the wild-type rat C6 glioma cells and the ASIC I a-silenced C6 cells were analyzed before and after acid application/exposure with the calcium imaging experiment. Results:The rapid extracellular pH drop induced the increase of [Ca2+]i in the wild-type C6 cells,but not in the ASICla-silenced C6 cells. During the prolonged acid exposure,[Ca2+]i was lower in the ASICla-silenced C6 cells than that in the control cells. Conclusion:The resultant toxicity of [Ca2+]i might contribute to the acidosis-induced cytotoxicity.

  16. μ-Opioid Agonist Inhibition of κ-Opioid Receptor-Stimulated Extracellular Signal-Regulated Kinase Phosphorylation Is Dynamin-Dependent in C6 Glioma Cells

    OpenAIRE

    Bohn, Laura M.; Belcheva, Mariana M.; Coscia, Carmine J.

    2000-01-01

    In previous studies we found that μ-opioids, acting via μ-opioid receptors, inhibit endothelin-stimulated C6 glioma cell growth. In the preceding article we show that the κ-selective opioid agonist U69,593 acts as a mitogen with a potency similar to that of endothelin in the same astrocytic model system. Here we report that C6 cell treatment with μ-opioid agonists for 1 h results in the inhibition of κ-opioid mitogenic signaling. The μ-selective agonist endomorphin-1 attenuates κ-opioid-stimu...

  17. Methylglyoxal alters glucose metabolism and increases AGEs content in C6 glioma cells.

    Science.gov (United States)

    Hansen, Fernanda; de Souza, Daniela Fraga; Silveira, Simone da Luz; Hoefel, Ana Lúcia; Fontoura, Júlia Bijoldo; Tramontina, Ana Carolina; Bobermin, Larissa Daniele; Leite, Marina Concli; Perry, Marcos Luiz Santos; Gonçalves, Carlos Alberto

    2012-12-01

    Methylglyoxal is a dicarbonyl compound that is physiologically produced by enzymatic and non-enzymatic reactions. It can lead to cytotoxicity, which is mainly related to Advanced Glycation End Products (AGEs) formation. Methylglyoxal and AGEs are involved in the pathogenesis of Neurodegenerative Diseases (ND) and, in these situations, can cause the impairment of energetic metabolism. Astroglial cells play critical roles in brain metabolism and the appropriate functioning of astrocytes is essential for the survival and function of neurons. However, there are only a few studies evaluating the effect of methylglyoxal on astroglial cells. The aim of this study was to evaluate the effect of methylglyoxal exposure, over short (1 and 3 h) and long term (24 h) periods, on glucose, glycine and lactate metabolism in C6 glioma cells, as well as investigate the glyoxalase system and AGEs formation. Glucose uptake and glucose oxidation to CO(2) increased in 1 h and the conversion of glucose to lipids increased at 3 h. In addition, glycine oxidation to CO(2) and conversion of glycine to lipids increased at 1 h, whereas the incorporation of glycine in proteins decreased at 1 and 3 h. Methylglyoxal decreased glyoxalase I and II activities and increased AGEs content within 24 h. Lactate oxidation and lactate levels were not modified by methylglyoxal exposure. These data provide evidence that methylglyoxal may impair glucose metabolism and can affect glyoxalase activity. In periods of increased methylglyoxal exposure, such alterations could be exacerbated, leading to further increases in intracellular methylglyoxal and AGEs, and therefore triggering and/or worsening ND.

  18. Influence of the spinning rate in the HR-MAS pattern of mobile lipids in C6 glioma cells and in artificial oil bodies.

    Science.gov (United States)

    Martín-Sitjar, Juana; Delgado-Goñi, Teresa; Cabañas, Miquel E; Tzen, Jason; Arús, Carles

    2012-12-01

    To evaluate how spinning rate affects mobile lipid (ML) resonances visibility in HR-MAS spectra of C6 glioma cells and artificial oil bodies (AOB), as models of cytosolic lipid droplets. Using C6 cells and AOB of two different sizes, 780 ± 580 and 240 ± 293 nm, as models, we acquired HR-MAS pulse and acquire spectra at different spinning rates between 500 and 15,000 Hz, all at 37 °C. Sample spinning at 15,000 Hz increased by 2.3 and 4.6-fold with respect to 500 Hz spinning the area of resonances corresponding to ML at 0.88 and 1.28 ppm, respectively, for log phase C6 cells. Furthermore, postconfluent C6 cells displayed an increase of 2.5-fold at 0.88 ppm and 4.2-fold at 1.28 ppm. These changes were reversible upon low speed spinning. AOBs did show much lower ML area increases (1.4-1.5-fold) upon high-speed HR-MAS. ML can be reversibly mobilized in C6 glioma cells by high-speed HR-MAS, partially unveiling the NMR "invisible" ML pool. A small part of the ML pool also shows reduced visibility in freely tumbling AOBs.

  19. The mechanisms of in vitro cytotoxicity of mountain tea, Sideritis scardica, against the C6 glioma cell line.

    Science.gov (United States)

    Jeremic, Ivica; Tadic, Vanja; Isakovic, Andjelka; Trajkovic, Vladimir; Markovic, Ivanka; Redzic, Zoran; Isakovic, Aleksandra

    2013-11-01

    Sideritis scardica (mountain tea) is an endemic plant on the Balkan Peninsula traditionally used for treating different conditions, mainly of inflammatory nature. This study was aimed to examine the cytotoxic activity of different S. scardica extracts against the rat glioma C6 line and rat astrocytes in primary culture. The obtained data revealed that diethyl ether (extract 2) and ethyl acetate (extract 3) extracts of S. scardica exerted a cytotoxic effect on C6 rat glioma cells. Diethyl ether extract induced an increase in reactive oxygen species production, leading to apoptotic and autophagic cell death. Ethyl acetate extract induced G2 M cell cycle arrest and autophagy. None of the tested extracts was cytotoxic to rat astrocytes in primary culture. Cytotoxic effects of S. scardica extracts were, at least in part, mediated by their flavonoid constituents apigenin and luteolin that, when applied alone, induced cell cycle arrest, apoptosis, and autophagy.

  20. CT perfusion imaging as an early biomarker of differential response to stereotactic radiosurgery in C6 rat gliomas.

    Directory of Open Access Journals (Sweden)

    Timothy Pok Chi Yeung

    Full Text Available BACKGROUND: The therapeutic efficacy of stereotactic radiosurgery for glioblastoma is not well understood, and there needs to be an effective biomarker to identify patients who might benefit from this treatment. This study investigated the efficacy of computed tomography (CT perfusion imaging as an early imaging biomarker of response to stereotactic radiosurgery in a malignant rat glioma model. METHODS: Rats with orthotopic C6 glioma tumors received either mock irradiation (controls, N = 8 or stereotactic radiosurgery (N = 25, 12 Gy in one fraction delivered by Helical Tomotherapy. Twelve irradiated animals were sacrificed four days after stereotactic radiosurgery to assess acute CT perfusion and histological changes, and 13 irradiated animals were used to study survival. Irradiated animals with survival >15 days were designated as responders while those with survival ≤15 days were non-responders. Longitudinal CT perfusion imaging was performed at baseline and regularly for eight weeks post-baseline. RESULTS: Early signs of radiation-induced injury were observed on histology. There was an overall survival benefit following stereotactic radiosurgery when compared to the controls (log-rank P<0.04. Responders to stereotactic radiosurgery showed lower relative blood volume (rBV, and permeability-surface area (PS product on day 7 post-stereotactic radiosurgery when compared to controls and non-responders (P<0.05. rBV and PS on day 7 showed correlations with overall survival (P<0.05, and were predictive of survival with 92% accuracy. CONCLUSIONS: Response to stereotactic radiosurgery was heterogeneous, and early selection of responders and non-responders was possible using CT perfusion imaging. Validation of CT perfusion indices for response assessment is necessary before clinical implementation.

  1. Fusions of Dendritic Cells and C6 Cells Transfected with TGF-β1 Antisense in Treatment of Intracranial Gliomas

    Institute of Scientific and Technical Information of China (English)

    Jin Gui-shan; Liu Fu-sheng; Chai Qi; Wang Jian-jao; Li Jun-hua

    2007-01-01

    Objective: To investigate the immunotherapy efficacy of fusion cells (dendritic-C6anti-TGF-β1 cells) in the treatment of intracranial gliomas. Methods: Dendritic cells were isolated from rat bone-marrow precursors stimulated in vitro with granulocyte-macrophage colony-stimulating factor (GM-CSF) and Interleukin-4 (IL-4). C6anti-TGF-β1 cells originally from C6 cell line of a rat glioblastoma were transfected with plasmid of TGF-β1 anti-sense gene. Fusions of dendritic cells and C6anti-TGF-β1 cells were prepared by polyethylene glycol (PEG). The DC/C6anti-TGF-β1 fusion cells were observed and confirmed by light microscopy and scanning electron microscopy. Experimental rats were divided into three groups at random: C6 cells (Ⅰ), dendritic-C6anti-TGF-β1 fusion cells and C6 cells (Ⅱ) and IMDM medium only (Ⅲ). The cells were injected into right parietal lobe region of the rat with stereotaxic technique. Histology, tumor necrosis and survival time were evaluated. Results: Compared with the rats that received C6 cells (survival median time was less than 20 days, tumor region was seen in all fields of observed), the rats injected with dendritic-C6anti-TGF-β1 fusion cells and C6 cells got a more prolonged life span (more than 59 days), as well as less tumor region (5.01%-6.2%). There was no tumor necrosis, but some glias were seen in surroundings. All rats were survived and no necrosis was observed in negative control group. Statistical analysis showed that group Ⅱ had significant difference compared with group Ⅰ. Conclusions: Dendritic-C6anti-TGF-β1 fusion cells could prolong the life span of rats, providing a strategy to achieve an antitumor response against tumors in the central nervous system.

  2. Paramagnetic Gd2O3 Nanoparticle-Based Targeting Theranostic Agent for C6 Rat Glioma Cell

    Directory of Open Access Journals (Sweden)

    Seong-Pyo Hong

    2016-01-01

    Full Text Available This study aimed to synthesize theranostic agent targeting C6 rat glioma cell, which was based on the dextran coated paramagnetic gadolinium oxide nanoparticles (D-PGONs conjugated with folic acid (FA or paclitaxel (PTX. The D-PGONs were synthesized by the in situ coprecipitation method, and the average value of the size distribution was 2.9 nm. FTIR spectroscopy was fulfilled to confirm the conjugations of FA or PTX with D-PGONs. The bioprotective effects of dextran coating and chemotherapeutic effect of PTX in the C6 glioma cell were evaluated by the MTT assay. The differences in uptakes between the synthesized theranostic agents into C6 cells were observed by confocal laser scanning microscopy. In addition, the magnetic contrast enhancement with different concentration of the synthesized agent was compared by the T1-weighted MRI imaging. It was experimentally shown that the synthesized theranostic agent targets C6 cells due to the ligand-receptor-mediated endocytosis and provides enhancement in MR contrast depending on the concentration due to the paramagnetic property of gadolinium nanoparticle. In addition, it was shown by the results of MTT assay that the synthesized nanocomposites were more effective in reducing cell viability than bare gadolinium nanoparticles. In conclusion, it was shown that FA and PTX conjugated D-PGONs could be used as the theranostic agent with paramagnetism and chemotherapeutic property.

  3. Orphan nuclear receptor Nur77 is required for the differentiation of C6 glioma cells induced by cholera toxin

    Institute of Scientific and Technical Information of China (English)

    Dong XU; Yi-jun HUANG; Yan LI; Wei YIN; Guang-mei YAN

    2009-01-01

    Aim: To investigate a possible regulator gene involved in the cholera toxin-induced differentiation of rat C6 glioma cells. Methods: The global changes in the mRNA expression pattern induced by cholera toxin were analyzed using gene chip microarray. The selected gene was then silenced by RNA interference or overexpressed with an ORF plasmid to determine its necessity in this process. Results: Nur77, a member of the orphan nuclear receptor family (NR4A), was markedly up-regulated during the process of differentiation. Furthermore, RNAi of nur77 attenuated the induction effect of cholera toxin on C6 cells, whereas overexpression of nur77 led to similarly differentiated behavior, including morphologic and biomarker changes, as well as cell cycle arrest. Conclusion: Nur77 participated actively and essentially as an important regulator in the cholera toxin-induced differentiation of C6 cells.

  4. Peroxide-induced cell death and lipid peroxidation in C6 glioma cells.

    Science.gov (United States)

    Linden, Arne; Gülden, Michael; Martin, Hans-Jörg; Maser, Edmund; Seibert, Hasso

    2008-08-01

    Peroxides are often used as models to induce oxidative damage in cells in vitro. The aim of the present study was to elucidate the role of lipid peroxidation in peroxide-induced cell death. To this end (i) the ability to induce lipid peroxidation in C6 rat astroglioma cells of hydrogen peroxide (H2O2), cumene hydroperoxide (CHP) and t-butyl hydroperoxide (t-BuOOH) (ii) the relation between peroxide-induced lipid peroxidation and cell death in terms of time and concentration dependency and (iii) the capability of the lipid peroxidation chain breaking alpha-tocopherol to prevent peroxide-induced lipid peroxidation and/or cell death were investigated. Lipid peroxidation was characterised by measuring thiobarbituric acid reactive substances (TBARS) and, by HPLC, malondialdehyde (MDA), 4-hydroxynonenal (4-HNE) and hexanal. Within 2 h CHP, t-BuOOH and H2O2 induced cell death with EC50 values of 59+/-9 microM, 290+/-30 microM and 12+/-1.1 mM, respectively. CHP and t-BuOOH, but not H2O2 induced lipid peroxidation in C6 cells with EC50 values of 15+/-14 microM and 130+/-33 microM, respectively. The TBARS measured almost exclusively consisted of MDA. 4-HNE was mostly not detectable. The concentration of hexanal slightly increased with increasing concentrations of organic peroxides. Regarding time and concentration dependency lipid peroxidation preceded cell death. Pretreatment with alpha-tocopherol (10 microM, 24 h) prevented both, peroxide-induced lipid peroxidation and cell death. The results strongly indicate a major role of lipid peroxidation in the killing of C6 cells by organic peroxides but also that lipid peroxidation is not involved in H2O2 induced cell death.

  5. Effect of extremely low frequency electromagnetic fields on rat C6 glioma cells in vivo%极低频电磁场暴露对大鼠脑内C6胶质细胞瘤的影响

    Institute of Scientific and Technical Information of China (English)

    周厚俊; 余化霖; 孙涛; 田冰峰; 周勇; 马以骝

    2012-01-01

      Objective To order to establish C6 rat intracerebral glioma model, investigate rat brain glioma impact by the way of extremely low frequency electromagnetic field exposure. Methods C6 cells were inplanted into all the SD rats, the number is 1×106 each rat. SD rat with intracranial C6 gliomas were established using stereotactic methods,then rats were randomly divided into treatment group(n=15) and control group(n=15). From 3 days after tumor inoculation, the rats in treatments group were exposesd three hours in the magnetic field every day ,it lasted a week, the control group were not exposed to magnetic field, during the time, we observe the spirit of rats, neural function(hemiplegia), the survival any time and death in rats with pathological biopsy autopsy. Results The rats of control group died in 16-27 days from the inoculation of C6 glioma cell, with an average survival of 22 days, while the rats of experimental group died in 21-33 days from the inoculation of C6 glioma cell, with an average survival of 26 days. Significant difference had happened between the experimental group and the control group(P<0.05). The C6 glioma were founded both in experimental group and control group. The morphological difference of the C6 glioma between the experimental group and the control group was not founded. Conclusion Extremely low frequency electromagnetic field exposure may be extended survival time of tumor-bearing rats, but it can not cure glioblastoma. Short-term exposure of low-intensity extremely low frequency electromagnetic field on patients with glioma has non-toxic or treatment, but long-term exposure of low-intensity extremely low frequency electromagnetic field may have a therapeutic effect on patients with glioma.%  目的通过建立荷瘤大鼠胶质瘤模型,探讨极低频电磁场暴露对大鼠脑内胶质细胞瘤的影响,为胶质瘤的实验性治疗提供理论依据.方法将1×106/ml的C6细胞悬液10μl注入

  6. Cytotoxic, Antiproliferative and Apoptotic Effects of New Benzimidazole Derivatives on A549 Lung Carcinoma and C6 Glioma Cell Lines.

    Science.gov (United States)

    Yurttas, Leyla; Demirayak, Seref; Ciftci, Gulsen Akalın

    2015-01-01

    Benzimidazole ring is a versatile structure which has been extensively utilized in medicinal chemistry. Since we are working on 1,2-disubstutited benzimidazoles, we have reported new antitumor active derivatives. As a continuation to our previous work, we have synthesized a new series of 1-(2-aryl-2-oxoethyl)-2-[(N,Ndimethylamino/pyrrolidinyl/piperidinyl)thiocarbamoyl] benzimidazole derivatives. Anticancer activity of the compounds was evaluated using MTT assay, BrdU assay and flow cytometric analysis on A549 human lung carcinoma and C6 rat glioma cell lines. Compounds bearing dimethylamino moiety exhibited higher antitumor activity.

  7. Evaluation of radiation effects against C6 glioma in combination with vaccinia virus-p53 gene therapy

    Science.gov (United States)

    Gridley, D. S.; Andres, M. L.; Li, J.; Timiryasova, T.; Chen, B.; Fodor, I.; Nelson, G. A. (Principal Investigator)

    1998-01-01

    The primary objective of this study was to evaluate the antitumor effects of recombinant vaccinia virus-p53 (rVV-p53) in combination with radiation therapy against the C6 rat glioma, a p53 deficient tumor that is relatively radioresistant. VV-LIVP, the parental virus (Lister strain), was used as a control. Localized treatment of subcutaneous C6 tumors in athymic mice with either rVV-p53 or VV-LIVP together with tumor irradiation resulted in low tumor incidence and significantly slower tumor progression compared to the agents given as single modalities. Assays of blood and spleen indicated that immune system activation may account, at least partly, for the enhance tumor inhibition seen with combined treatment. No overt signs of treatment-related toxicity were noted.

  8. ROS enhancement by silicon nanoparticles in X-ray irradiated aqueous suspensions and in glioma C6 cells

    Science.gov (United States)

    David Gara, Pedro M.; Garabano, Natalia I.; Llansola Portoles, Manuel J.; Moreno, M. Sergio; Dodat, Diego; Casas, Oscar R.; Gonzalez, Mónica C.; Kotler, Mónica L.

    2012-03-01

    The capability of silicon nanoparticles to increase the yield of reactive species upon 4 MeV X-ray irradiation of aqueous suspensions and C6 glioma cell cultures was investigated. ROS generation was detected and quantified using several specific probes. The particles were characterized by FTIR, XPS, TEM, DLS, luminescence, and adsorption spectroscopy before and after irradiation to evaluate the effect of high energy radiation on their structure. The total concentration of O2 •-/HO2 •, HO•, and H2O2 generated upon 4-MeV X-ray irradiation of 6.4 μM silicon nanoparticle aqueous suspensions were on the order of 10 μM per Gy, ten times higher than that obtained in similar experiments but in the absence of particles. Cytotoxic 1O2 was generated only in irradiation experiments containing the particles. The particle surface became oxidized to SiO2 and the luminescence yield reduced with the irradiation dose. Changes in the surface morphology did not affect, within the experimental error, the yields of ROS generated per Gy. X-ray irradiation of glioma C6 cell cultures with incorporated silicon nanoparticles showed a marked production of ROS proportional to the radiation dose received. In the absence of nanoparticles, the cells showed no irradiation-enhanced ROS generation. The obtained results indicate that silicon nanoparticles of design of therapy strategies.

  9. Generation of Brain Microvascular Endothelial-Like Cells from Human Induced Pluripotent Stem Cells by Co-Culture with C6 Glioma Cells.

    Directory of Open Access Journals (Sweden)

    Haruka Minami

    Full Text Available The blood brain barrier (BBB is formed by brain microvascular endothelial cells (BMECs and tightly regulates the transport of molecules from blood to neural tissues. In vitro BBB models from human pluripotent stem cell (PSCs-derived BMECs would be useful not only for the research on the BBB development and function but also for drug-screening for neurological diseases. However, little is known about the differentiation of human PSCs to BMECs. In the present study, human induced PSCs (iPSCs were differentiated into endothelial cells (ECs, and further maturated to BMECs. Interestingly, C6 rat glioma cell-conditioned medium (C6CM, in addition to C6 co-culture, induced the differentiation of human iPSC-derived ECs (iPS-ECs to BMEC-like cells, increase in the trans-endothelial electrical resistance, decreased in the dextran transport and up-regulation of gene expression of tight junction molecules in human iPS-ECs. Moreover, Wnt inhibitors attenuated the effects of C6CM. In summary, we have established a simple protocol of the generation of BMEC-like cells from human iPSCs, and have demonstrated that differentiation of iPS-ECs to BMEC-like cells is induced by C6CM-derived signals, including canonical Wnt signals.

  10. Generation of Brain Microvascular Endothelial-Like Cells from Human Induced Pluripotent Stem Cells by Co-Culture with C6 Glioma Cells.

    Science.gov (United States)

    Minami, Haruka; Tashiro, Katsuhisa; Okada, Atsumasa; Hirata, Nobue; Yamaguchi, Tomoko; Takayama, Kazuo; Mizuguchi, Hiroyuki; Kawabata, Kenji

    2015-01-01

    The blood brain barrier (BBB) is formed by brain microvascular endothelial cells (BMECs) and tightly regulates the transport of molecules from blood to neural tissues. In vitro BBB models from human pluripotent stem cell (PSCs)-derived BMECs would be useful not only for the research on the BBB development and function but also for drug-screening for neurological diseases. However, little is known about the differentiation of human PSCs to BMECs. In the present study, human induced PSCs (iPSCs) were differentiated into endothelial cells (ECs), and further maturated to BMECs. Interestingly, C6 rat glioma cell-conditioned medium (C6CM), in addition to C6 co-culture, induced the differentiation of human iPSC-derived ECs (iPS-ECs) to BMEC-like cells, increase in the trans-endothelial electrical resistance, decreased in the dextran transport and up-regulation of gene expression of tight junction molecules in human iPS-ECs. Moreover, Wnt inhibitors attenuated the effects of C6CM. In summary, we have established a simple protocol of the generation of BMEC-like cells from human iPSCs, and have demonstrated that differentiation of iPS-ECs to BMEC-like cells is induced by C6CM-derived signals, including canonical Wnt signals.

  11. 替莫唑胺联合姜黄素对C6胶质瘤细胞凋亡的作用%Effect of temozolomide combined with curcumin on the apoptosis of the C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    王亚华; 应雪; 张春春; 轩亚茹; 闫荷露; 李霞

    2016-01-01

    目的:研究替莫唑胺联合姜黄素用药对 C6胶质瘤细胞的抑制作用和诱导凋亡作用。方法:SRB 法考察替莫唑胺联合姜黄素对 C6细胞的抑制作用;流式细胞法检测联合用药对 C6细胞的凋亡作用;激光共聚焦扫描显微镜观察联合用药对细胞的诱导作用及在细胞中的定位作用。结果: SRB 法结果显示替莫唑胺联合姜黄素在48 h 时对 C6细胞的抑制率为(91.22±0.51)%,显著高于24 h 的抑制率(83.66±0.18)%(P <0.05);流式细胞仪检测结果表明,替莫唑胺(10μmol/L)联合姜黄素(5μmol/L)用药时 C6细胞的早期凋亡率为(33.15±0.79)%;通过激光共聚焦扫描显微镜观察,姜黄素联合替莫唑胺组诱导 C6细胞的凋亡细胞数量多于游离药物组。结论:替莫唑胺联合姜黄素用药能够抑制 C6细胞的生长,同时可诱导C6细胞的凋亡。%Objective To study the temozolomide combined with curcumin on the inhibitory effect and apoptosis of the C6 glioma cells. Methods The C6 glioma cells were treated with temozomide in combination with curcumin. The anti proliferation effect of liposomes on the C6 glioma cells was investigated by using the method of sulforhodamine B (SRB). Flow cytometry was used to detect apoptosis of the C6 glioma cells. Confocal laser scan-ning microscope was used to observe apoptosis and location in the C6 glioma cells. Results The results of SRB as-say showed that temozolomide in combination with curcumin inhibition rate were (91.22 ± 0.51)%in 48 h of the C6 glioma cells; Flow cytometry showed that the apoptosis rate were (33.15 ± 0.79)% with temozolomide (5 μmol/L) in combination with curcumin (10 μmol/L). Laser scanning confocal scanning microscope indicated that the apop-tosis of in the C6 glioma cells treated with temozolomide in combination with curcumin was more than that of free drug. Conclusion The temozolomide in combination of

  12. Involvement of tumor suppressor protein p53 and p38 MAPK in caffeic acid phenethyl ester-induced apoptosis of C6 glioma cells.

    Science.gov (United States)

    Lee, Yean-Jang; Kuo, Hsing-Chun; Chu, Chia-Yih; Wang, Chau-Jong; Lin, Wan-Chyi; Tseng, Tsui-Hwa

    2003-12-15

    Caffeic acid phenethyl ester (CAPE), an active component of propolis, has many biological and pharmacological activities including antioxidant, anti-inflammation, antiviral action, and anticancer effect. Our previous studies showed that CAPE exhibited significant cytotoxicity in oral cancer cells. Herein we further investigated the cytotoxicity potential of CAPE and the mechanism of its action in C6 glioma cells. The data exhibited that C6 glioma cells underwent internucleosomal DNA fragmentation 24 hr after the treatment of CAPE (50 microM). The proportion of C6 glioma cells with hypodiploid nuclei was increased to 24% at 36 hr after the exposure. Further results showed that CAPE induced the release of cytochrome c from mitochondria into cytosol, and the activation of CPP32. CAPE application also enhanced the expression of p53, Bax, and Bak. Finally, the potential signaling components underlying CAPE induction of apoptosis were elucidated. We found that CAPE activated extracellular signal-regulated kinase (ERKs) and p38 mitogen-activated protein kinase (p38 MAPK) in C6 glioma cells. More importantly, p38 kinase formed a complex with p53 after the treatment of CAPE for 0.5 hr. The expression of p53, phospho-serine 15 of p53, and Bax, and inactivate form of CPP32 was suppressed by a pretreatment of a specific p38 MAPK inhibitor, SB203580. The resultant data suggest that p38 MAPK mediated the CAPE-induced p53-dependent apoptosis in C6 glioma cells.

  13. ROS enhancement by silicon nanoparticles in X-ray irradiated aqueous suspensions and in glioma C6 cells

    Energy Technology Data Exchange (ETDEWEB)

    David Gara, Pedro M. [CITOMA, Fundacion Avanzar, Instituto de Terapia Radiante S.A., CIO La Plata (Argentina); Garabano, Natalia I. [University of Buenos Aires, Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, UBA (Argentina); Llansola Portoles, Manuel J. [UNLP, INIFTA, Departamento de Quimica, Facultad de Ciencias Exactas (Argentina); Moreno, M. Sergio [Centro Atomico Bariloche (Argentina); Dodat, Diego; Casas, Oscar R. [CITOMA, Fundacion Avanzar, Instituto de Terapia Radiante S.A., CIO La Plata (Argentina); Gonzalez, Monica C., E-mail: gonzalez@inifta.unlp.edu.ar [UNLP, INIFTA, Departamento de Quimica, Facultad de Ciencias Exactas (Argentina); Kotler, Monica L., E-mail: kotler@qb.fcen.uba.ar [University of Buenos Aires, Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, UBA (Argentina)

    2012-03-15

    The capability of silicon nanoparticles to increase the yield of reactive species upon 4 MeV X-ray irradiation of aqueous suspensions and C6 glioma cell cultures was investigated. ROS generation was detected and quantified using several specific probes. The particles were characterized by FTIR, XPS, TEM, DLS, luminescence, and adsorption spectroscopy before and after irradiation to evaluate the effect of high energy radiation on their structure. The total concentration of O{sub 2}{sup Bullet -}/HO{sub 2}{sup Bullet}, HO{sup Bullet}, and H{sub 2}O{sub 2} generated upon 4-MeV X-ray irradiation of 6.4 {mu}M silicon nanoparticle aqueous suspensions were on the order of 10 {mu}M per Gy, ten times higher than that obtained in similar experiments but in the absence of particles. Cytotoxic {sup 1}O{sub 2} was generated only in irradiation experiments containing the particles. The particle surface became oxidized to SiO{sub 2} and the luminescence yield reduced with the irradiation dose. Changes in the surface morphology did not affect, within the experimental error, the yields of ROS generated per Gy. X-ray irradiation of glioma C6 cell cultures with incorporated silicon nanoparticles showed a marked production of ROS proportional to the radiation dose received. In the absence of nanoparticles, the cells showed no irradiation-enhanced ROS generation. The obtained results indicate that silicon nanoparticles of <5 nm size have the potential to be used as radiosensitizers for improving the outcomes of cancer radiotherapy. Their capability of producing {sup 1}O{sub 2} upon X-ray irradiation opens novel approaches in the design of therapy strategies.

  14. Biodegradable microparticles and fiber fabrics for sustained delivery of cisplatin to treat C6 glioma in vitro.

    Science.gov (United States)

    Xie, Jingwei; Tan, Ruo Shan; Wang, Chi-Hwa

    2008-06-15

    The duration of cisplatin release from most of the drug delivery devices seemed to be shorter than 14 days except large microparticles. The objective of this study was to fabricate and characterize cisplatin-loaded PLA microparticles, PLA/PLGA (30/70) composite microparticles, and fibers as formulations for long-term sustained delivery of cisplatin to treat C6 glioma in vitro by electrospray and electrospinning techniques. Cisplatin-loaded biodegradable microparticles with particle size of around 5 microm and fiber fabrics with diameter of 0.5-1.7 microm were obtained using electrospray and electrospinning techniques. Encapsulation efficiency and in vitro release of formulations were measured by ICP-OES. The encapsulation efficiency for different samples of microparticles was approximately from 33% to 72% and the fiber fabrics had encapsulation efficiency greater than 90%. Cisplatin-loaded microparticles showed typical characteristics of cisplatin release profile: a large initial burst followed by a sustained slow release of 35 days. The composite PLA/PLGA (30/70) microparticles could reduce the initial burst release of cisplatin because of their core-shell structures. In contrast, more than 75 days sustained release could be achieved by fiber fabric formulations without large initial burst. MTT assay was used to quantify the cytotoxicity of different formulations against C6 glioma cells. Microparticle formulations had slightly higher cytotoxicity than free drug. In contrast, the cytotoxicity of fiber fabrics formulation was around 4 times higher than of the free drug based on the actual amount of drug released. The microparticle and fiber fabric formulations presented may be promising for the sustained delivery of cisplatin to eliminate the undesired side effects caused by direct injection of cisplatin solution in systemic administration.

  15. Cold atmospheric-pressure air plasma treatment of C6 glioma cells: effects of reactive oxygen species in the medium produced by the plasma on cell death

    Science.gov (United States)

    Wang, Yuyang; Cheng, Cheng; Gao, Peng; Li, Shaopeng; Shen, Jie; Lan, Yan; Yu, Yongqiang; Chu, Paul K.

    2017-02-01

    An atmospheric-pressure air plasma is employed to treat C6 glioma cells in vitro. To elucidate on the mechanism causing cell death and role of reactive species (RS) in the medium produced by the plasma, the concentration of the long-lived RS such as hydrogen peroxide, nitrate, and ozone in the plasma-treated liquid (phosphate-buffered saline solution) is measured. When vitamin C is added to the medium as a ROS quencher, the viability of C6 glioma cells after the plasma treatment is different from that without vitamin C. The results demonstrate that reactive oxygen species (ROS) such as H2O2, and O3 constitute the main factors for inactivation of C6 glioma cells and the reactive nitrogen species (RNS) may only play an auxiliary role in cell death.

  16. Cold atmospheric-pressure air plasma treatment of C6 glioma cells: effects of reactive oxygen species in the medium produced by the plasma on cell death

    Science.gov (United States)

    Yuyang, Wang; Cheng, Cheng; Peng, Gao; Shaopeng, Li; Jie, Shen; Yan, Lan; Yongqiang, Yu; Paul, K. Chu

    2017-02-01

    An atmospheric-pressure air plasma is employed to treat C6 glioma cells in vitro. To elucidate on the mechanism causing cell death and role of reactive species (RS) in the medium produced by the plasma, the concentration of the long-lived RS such as hydrogen peroxide, nitrate, and ozone in the plasma-treated liquid (phosphate-buffered saline solution) is measured. When vitamin C is added to the medium as a ROS quencher, the viability of C6 glioma cells after the plasma treatment is different from that without vitamin C. The results demonstrate that reactive oxygen species (ROS) such as H2O2, and O3 constitute the main factors for inactivation of C6 glioma cells and the reactive nitrogen species (RNS) may only play an auxiliary role in cell death.

  17. Intra-individual comparison of different gadolinium-based contrast agents in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging.

    Science.gov (United States)

    Li, Ying; Liu, Gang; Lou, Xin; Chen, Zhiye; Ma, Lin

    2017-01-01

    This experiment aimed to compare the ionic (Gadodiamide, Gd-DTPA-BMA) and non-ionic (Gadopentetate dimeglumine, Gd-DTPA) gadolinium-based contrast agents (GBCA) in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). A C6 glioma model was established in 12 Wistar rats, and magnetic resonance (MR) scans were performed six days after tumor implantation. Imaging was performed using a 3.0-T MR scanner with a 7-inch handmade circular coil. Pre-contrast T1 mapping and dynamic contrast-enhanced T1WI after a bolus injection (0.2 mL s(-1)) of GBCA at 0.4 mmol kg(-1) were performed. Each rat received two DCE-MRI scans, 24 h apart. The first and second scans were performed using Gd-DTPA-BMA and Gd-DTPA, respectively. Image data were processed using the Patlak model. Both K (trans) and V p maps were generated. Tumors were manually segmented on all 3D K (trans) and V p maps. Pixel counts and mean values were recorded for use in a paired t-test. Three radiologists independently performed the tumor segmentation and value calculation. The agreements from different observers were subjective to the intra-class correlation coefficient (ICC). Readers demonstrated that the pixel counts of tumors in K (trans) maps were higher with Gd-DTPA-BMA than with Gd-DTPA (P0.05, all readers). The pixel counts of tumors in V p maps, as well as V p values, showed no obvious difference between the two agents (P>0.05, all readers). Excellent interobserver measurement reproducibility and reliability were demonstrated in the ICC tests. The Gd-DTPA-BMA contrast agent had significantly higher pixel counts of glioma in the K (trans) maps, and an increased tendency for average K (trans) values, indicating that DCE-MRI with Gd-DTPA-BMA may be more suitable and sensitive for the evaluation of glioma.

  18. Effects of quercetin and quercetin-3-O-glycosides on oxidative damage in rat C6 glioma cells.

    Science.gov (United States)

    Zielińska, Małgorzata; Gülden, Michael; Seibert, Hasso

    2003-01-01

    Flavonoids are reported to be powerful antioxidants in cell free systems. They naturally occur as glycosides rather than as aglycon. In this study the ability of the flavonoid quercetin and its glycosides, quercetin-3-O-rutinoside (rutin), quercetin-3-O-glucoside and quercetin-3-O-(6″-O-acetyl)-glucoside, to protect in vitro rat C6 glioma cells from oxidative damage induced by cumene hydroperoxide was investigated. Cumene hydroperoxide induced cell death and lipid peroxidation. The cytotoxicity of cumene hydroperoxide could be prevented by the radical scavenger dimethyl thiourea and the ferric iron chelator deferoxamine, indicating that its cytotoxic activity is related to the generation of reactive oxygen radicals in the ferrous iron dependent Fenton reaction. Quercetin, in a concentration range of 10-100 μM, but neither rutin nor the other two glycosides, were able to protect C6 cells from cytotoxicity and lipid peroxidation. Furthermore, cytoprotective concentrations of quercetin proved to be cytotoxic itself. These results call in question potential beneficial effects of dietary intake or therapeutic use of naturally occurring flavonoids.

  19. Targeted delivery of vitamin D3-loaded nanoparticles to C6 glioma cell line increased resistance to doxorubicin, epirubicin, and docetaxel in vitro.

    Science.gov (United States)

    Maleklou, Nargess; Allameh, Abdolamir; Kazemi, Bahram

    2016-12-01

    In recent years, targeted delivery systems have been used along with combinatorial therapy to decrease drug resistance and increase cancer therapy efficacy. The anti-proliferative effects of vitamin D3 (VD3) on cancerous cells, such as C6 glioma, with active hedgehog pathways raised the question as to whether pre-targeting C6 glioma cells with VD3-loaded nanoparticles (VD3NPs) can enhance the anti-tumor effects of doxorubicin, epirobicin, and docetaxel on this drug-resistant cell line. Here, studying at cellular, nuclear, protein, and gene levels we demonstrated that VD3NP-doxorubicin and VD3NP-epirobicin combinations increased the probability of chemotherapy/radiotherapy resistance and cancer stem cell (CSC) properties in C6 glioma significantly (P doxorubicin and epirobicin alone. However, VD3NP-docetaxel combination may have the potential in sensitizing C6 cells to ionizing irradiation, but this combination also increased the CSC properties and the probability of drug resistance significantly (P doxorubicin, epirobicin, and docetaxel not only did not lead to the enhancement of cytotoxic effects of the aforementioned drugs but also increased the cancerous characteristics in C6 glioma, in vitro.

  20. Cas Ilgly Induces Apoptosis in Glioma C6 Cells In Vitro and In Vivo through Caspase-Dependent and Caspase-Independent Mechanisms

    Directory of Open Access Journals (Sweden)

    Cristina Trejo-Solís

    2005-06-01

    Full Text Available In this work, we investigated the effects of Casiopeina Il-gly (Cas ILgly—a new copper compound exhibiting antineoplastic activity—on glioma C6 cells under both in vitro and in vivo conditions, as an approach to identify potential therapeutic agents against malignant glioma. The exposure of C6 cells to Cas Ilgly significantly inhibited cell proliferation, increased reactive oxygen species (ROS formation, and induced apoptosis in a dose-dependent manner. In cultured C6 cells, Cas Ilgly caused mitochondrio-nuclear translocation of apoptosis induction factor (AIF and endonuclease G at all concentrations tested; in contrast, fragmentation of nucleosomal DNA, cytochrome c release, and caspase-3 activation were observed at high concentrations. Administration of N-acetyl-l-cystein, an antioxidant, resulted in significant inhibition of AIF translocation, nucleosomal DNA fragmentation, and caspase-3 activation induced by Cas Ilgly. These results suggest that caspase-dependent and caspase-independent pathways both participate in apoptotic events elicited by Cas Ilgly. ROS formation induced by Cas Ilgly might also be involved in the mitochondrio-nuclear translocation of AIF and apoptosis. In addition, treatment of glioma C6-positive rats with Cas Ilgly reduced tumor volume and mitotic and cell proliferation indexes, and increased apoptotic index. Our findings support the use of Cas Ilgly for the treatment of malignant gliomas.

  1. In vivo glioblastoma growth is reduced by apyrase activity in a rat glioma model

    Directory of Open Access Journals (Sweden)

    Meurer Luise

    2006-09-01

    Full Text Available Abstract Background ATP is an important signalling molecule in the peripheral and central nervous system. Both glioma growth and tumor resection induces cell death, thus liberating nucleotides to the extracellular medium. Nucleotides are hydrolyzed very slowly by gliomas when compared with astrocytes and induce neuronal cell death and glioma proliferation. The objective of the present study was to test the involvement of extracellular ATP in glioblastoma growth in a rat glioma model. Methods To deplete the extracellular ATP, the enzyme apyrase was tested on the treatment of gliomas implanted in the rats CNS. One million glioma C6 cells in 3 microliters of DMEM/FCS were injected in the right striata of male Wistar rats, 250–270 g. After 20 days, the rats were decapitated and the brain sectioning and stained with hematoxylin and eosine. We performed immunohistochemical experiments with Ki67, CD31 and VEGF. Total RNA was isolated from cultured glioma C6 cells and the cDNA was analyzed by Real Time-PCR with primers for the NTPDase family. Results C6 glioma cells effectively have a low expression of all NTPDases investigated, in comparison with normal astrocytes. The implanted glioma co-injected with apyrase had a significant reduction in the tumor size (p Conclusion These results indicate that the participation of extracellular ATP and the ecto-nucleotidases may be associated with the development of this type of brain tumor in an in vivo glioma model.

  2. 替莫唑胺壳聚糖微球的构建及对 C6细胞抑制作用的评价%The preparation and inhibition on C6 glioma cells of Temozolomide chitosan microspheres

    Institute of Scientific and Technical Information of China (English)

    袁苗苗; 张春春; 王亚华; 朱佳; 轩亚茹; 应雪

    2014-01-01

    Objective:Temozolomide chitosan microspheres was prepared and investigated the preparation technolo -gy,then studied the inhibitory effect of C 6 glioma cells.Methods:The amount of temozolomide which in nanospheres was analyzed by ultraviolet spectrophotometry .Temozolomide chitosan microspheres was prepared by emulsion-chemical crosslink technique ,with using chitosan as a carrier .The preparation process of microspheres was optimized by temozolomide encapsu-lation efficiency as index .The particles size and morphological characteristics of chitosan microspheres were observed by mi -croscopic.And SRB method was used to study the anti-tumor effect of temozolomide chitosan microspheres on C 6 glioma cells.Results:The temozolomide chitosan microspheres were spherical in shape and even in particle size .The mean diame-ter was(217 ±1.19) nm and the average entrapment efficifency of temozolomide chitosan microspheres was 27.6 ±0. 37%.And have significant inhibitory effects on C 6 glioma cells than free temozolomide .Conclusion:The temozolomide chi-tosan microspheres was tability and have sustained release effect .And have a significantly inhibited on C 6 glioma cells.%目的:考察替莫唑胺壳聚糖微球的制备工艺,并对C6脑胶质瘤细胞的抑制作用进行了研究。方法:采用紫外分光光度法测定微球中替莫唑胺的含量,以壳聚糖为载体,采用乳化-化学交联法制备替莫唑胺壳聚糖微球;以替莫唑胺包封率为评价指标进行微球制备工艺的筛选;显微镜观察微球形态学特征;SRB法考察替莫唑胺壳聚糖微球体外抗肿瘤作用。结果:所制得微球形态圆整,粒径分布均匀,平均粒径为(217±1.19) nm,包封率为27.6±0.37%,对C6胶质瘤细胞具有显著的抑制作用。结论:本法制备替莫唑胺壳聚糖微球的工艺稳定,且对C6胶质瘤细胞具有显著的抑制作用。

  3. Heat shock induction of a 65 kDa ATP—binding proteinase in rat C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    XUCUNSHUAN; MARCOMEYER; 等

    1999-01-01

    The 45,55,65 and 100kDa ATP-binding proteinases(ATP-BPases) of the heat-shocked (44℃ for 30 min,recovery for 12h) rat C6 glioma cells were purified by DEAE-ionexchange and ATP-affinity chromatography.Their molecular masses,isoelectric points (pI),pH-optima and other properties were analyzed by native proteinase gels.It was shown that the 65 kDa ATP-BPase is specifically induced by heat shock and not detectable in control cells.Its N-terminal 1-9amino acid sequence was determined by Edman degradation,but no homologies to other proteins in the protein data bases were found.30 and 31kDa proteinases can be cleaved from the 45,55 and 65 kDa proteinases to which they are linked.A possible relationship of the heat-induced 65 kDa ATP-BPase with the ATP-dependent proteinases (ATP-DPases) in prokaryotes and eukaryotes is discussed.

  4. Induction of cell cycle arrest at G1 and S phases and cAMP-dependent differentiation in C6 glioma by low concentration of cycloheximide

    Directory of Open Access Journals (Sweden)

    Zhang Samuel S

    2010-12-01

    Full Text Available Abstract Background Differentiation therapy has been shown effective in treatment of several types of cancer cells and may prove to be effective in treatment of glioblastoma multiforme, the most common and most aggressive primary brain tumor. Although extensively used as a reagent to inhibit protein synthesis in mammalian cells, whether cycloheximide treatment leads to glioma cell differentiation has not been reported. Methods C6 glioma cell was treated with or without cycloheximide at low concentrations (0.5-1 μg/ml for 1, 2 and 3 days. Cell proliferation rate was assessed by direct cell counting and colony formation assays. Apoptosis was assessed by Hoechst 33258 staining and FACS analysis. Changes in several cell cycle regulators such as Cyclins D1 and E, PCNA and Ki67, and several apoptosis-related regulators such as p53, p-JNK, p-AKT, and PARP were determined by Western blot analysis. C6 glioma differentiation was determined by morphological characterization, immunostaining and Western blot analysis on upregulation of GFAP and o p-STAT3 expression, and upregulation of intracellular cAMP. Results Treatment of C6 cell with low concentration of cycloheximide inhibited cell proliferation and depleted cells at both G2 and M phases, suggesting blockade at G1 and S phases. While no cell death was observed, cells underwent profound morphological transformation that indicated cell differentiation. Western blotting and immunostaining analyses further indicated that changes in expression of several cell cycle regulators and the differentiation marker GFAP were accompanied with cycloheximide-induced cell cycle arrest and cell differentiation. Increase in intracellular cAMP, a known promoter for C6 cell differentiation, was found to be elevated and required for cycloheximide-promoted C6 cell differentiation. Conclusion Our results suggest that partial inhibition of protein synthesis in C6 glioma by low concentration of cycloheximide induces cell cycle

  5. Andrographolide Induces Apoptosis of C6 Glioma Cells via the ERK-p53-Caspase 7-PARP Pathway

    Directory of Open Access Journals (Sweden)

    Shih-Hung Yang

    2014-01-01

    Full Text Available Background. Glioma is the most malignant tumor of the central nervous system. Efforts on the development of new chemotherapy are mandatory. Andrographolide (AND, a diterpenoid lactone isolated from the Andrographis paniculata, has been shown to have antitumor activities in several types of cancer cells. Whether AND can exert its antitumor activity in glioblastoma cells remains unknown. This study examined the anticancer effects of AND, both in vitro and in vivo. Methods. Cell apoptosis was assayed by flow cytometry and nuclear staining. The signaling pathway for AND was determined by western blotting. The effects of AND on tumor growth was evaluated in a mouse model. Results and Conclusion. In vitro, with application of specific inhibitors and siRNA, AND-induced apoptosis was proven through ROS-ERK-P53-caspase 7-PARP signaling pathway. In vivo, AND significantly retarded tumor growth and caused regression of well-formed tumors in vivo. Furthermore, AND did not induce apoptosis or activate ERK and p53 in primary cultured astrocyte cells, and it may serve as a potential therapeutic candidate for the treatment of glioma.

  6. Gamma-linolenic acid inhibits both tumour cell cycle progression and angiogenesis in the orthotopic C6 glioma model through changes in VEGF, Flt1, ERK1/2, MMP2, cyclin D1, pRb, p53 and p27 protein expression

    Directory of Open Access Journals (Sweden)

    Colquhoun Alison

    2009-03-01

    Full Text Available Abstract Background Gamma-linolenic acid is a known inhibitor of tumour cell proliferation and migration in both in vitro and in vivo conditions. The aim of the present study was to determine the mechanisms by which gamma-linolenic acid (GLA osmotic pump infusion alters glioma cell proliferation, and whether it affects cell cycle control and angiogenesis in the C6 glioma in vivo. Methods Established C6 rat gliomas were treated for 14 days with 5 mM GLA in CSF or CSF alone. Tumour size was estimated, microvessel density (MVD counted and protein and mRNA expression measured by immunohistochemistry, western blotting and RT-PCR. Results GLA caused a significant decrease in tumour size (75 ± 8.8% and reduced MVD by 44 ± 5.4%. These changes were associated with reduced expression of vascular endothelial growth factor (VEGF (71 ± 16% and the VEGF receptor Flt1 (57 ± 5.8% but not Flk1. Expression of ERK1/2 was also reduced by 27 ± 7.7% and 31 ± 8.7% respectively. mRNA expression of matrix metalloproteinase-2 (MMP2 was reduced by 35 ± 6.8% and zymography showed MMP2 proteolytic activity was reduced by 32 ± 8.5%. GLA altered the expression of several proteins involved in cell cycle control. pRb protein expression was decreased (62 ± 18% while E2F1 remained unchanged. Cyclin D1 protein expression was increased by 42 ± 12% in the presence of GLA. The cyclin dependent kinase inhibitors p21 and p27 responded differently to GLA, p27 expression was increased (27 ± 7.3% while p21 remained unchanged. The expression of p53 was increased (44 ± 16% by GLA. Finally, the BrdU incorporation studies found a significant inhibition (32 ± 11% of BrdU incorporation into the tumour in vivo. Conclusion Overall the findings reported in the present study lend further support to the potential of GLA as an inhibitor of glioma cell proliferation in vivo and show it has direct effects upon cell cycle control and angiogenesis. These effects involve changes in protein

  7. Detecting response of rat C6 glioma tumors to radiotherapy using hyperpolarized [1-13C]pyruvate and 13C magnetic resonance spectroscopic imaging

    OpenAIRE

    Day, Sam E.; Kettunen, Mikko I.; Cherkuri, Murali Krishna; James B Mitchell; Lizak, Martin J.; Morris, H. Douglas; Koretsky, Alan P.; Brindle, Kevin M.

    2010-01-01

    13C chemical shift images acquired following intravenous injection of hyperpolarized [1-13C]pyruvate into rats with implanted C6 gliomas showed significant labeling of lactate within the tumors but not in surrounding brain tissue. Signal from pyruvate was observed in blood vessels above the brain and from other major vessels elsewhere in the rat head. Pyruvate was largely undetectable within the tumor or surrounding normal brain tissue. The ratio of hyperpolarized 13C label in the injected py...

  8. Fibroblast growth factor-2 up-regulates the expression of nestin through the Ras–Raf–ERK–Sp1 signaling axis in C6 glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Kai-Wei [Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan (China); Huang, Yuan-Li [Department of Biotechnology, College of Health Science, Asia University, Taichung 413, Taiwan (China); Wong, Zong-Ruei; Su, Peng-Han [Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan (China); Huang, Bu-Miin [Department of Cell Biology and Anatomy, National Cheng-Kung University, Tainan 701, Taiwan (China); Ju, Tsai-Kai [Instrumentation Center, National Taiwan University, Taipei 106, Taiwan (China); Technology Commons, College of Life Science, National Taiwan University, Taipei 106, Taiwan (China); Yang, Hsi-Yuan, E-mail: hyhy@ntu.edu.tw [Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan (China)

    2013-05-17

    Highlights: •Nestin expression in C6 glioma cells is induced by FGF-2. •Nestin expression is induced by FGF-2 via de novo RNA and protein synthesis. •The FGFR inhibitor SU5402 blocks the FGF-2-induced nestin expression. •The mRNA of FGFR1 and 3 are detected in C6 glioma cells. •Ras–Raf–ERK–Sp1 signaling pathway is responsibe for FGF-2-induced nestin expression. -- Abstract: Nestin is a 240-kDa intermediate filament protein expressed mainly in neural and myogenic stem cells. Although a substantial number of studies have focused on the expression of nestin during development of the central nervous system, little is known about the factors that induce and regulate its expression. Fibroblast growth factor-2 (FGF-2) is an effective mitogen and stimulates the proliferation and differentiation of a subset of nestin-expressing cells, including neural progenitor cells, glial precursor cells, and smooth muscle cells. To assess whether FGF-2 is a potent factor that induces the expression of nestin, C6 glioma cells were used. The results showed that nestin expression was up-regulated by FGF-2 via de novo RNA and protein synthesis. Our RT-PCR results showed that C6 glioma cells express FGFR1/3, and FGFRs is required for FGF-2-induced nestin expression. Further signaling analysis also revealed that FGF-2-induced nestin expression is mediated through FGFR–MAPK–ERK signaling axis and the transcriptional factor Sp1. These findings provide new insight into the regulation of nestin in glial system and enable the further studies on the function of nestin in glial cells.

  9. Comparative effects on rat primary astrocytes and C6 rat glioma cells cultures after 24-h exposure to silver nanoparticles (AgNPs)

    Energy Technology Data Exchange (ETDEWEB)

    Salazar-García, Samuel; Silva-Ramírez, Ana Sonia; Ramirez-Lee, Manuel A.; Rosas-Hernandez, Hector [Universidad Autonoma de San Luis Potosi, Facultad de Ciencias Quimicas (Mexico); Rangel-López, Edgar [Instituto Nacional de Neurologia y Neurocirugia Manuel Velasco Suárez, Laboratorio de Aminoacidos Excitadores (Mexico); Castillo, Claudia G. [Facultad de Medicina, Universidad Autonoma de San Luis Potosi (Mexico); Santamaría, Abel [Instituto Nacional de Neurologia y Neurocirugia Manuel Velasco Suárez, Laboratorio de Aminoacidos Excitadores (Mexico); Martinez-Castañon, Gabriel A. [Universidad Autonoma de San Luis Potosi, Facultad de Estomatologia (Mexico); Gonzalez, Carmen, E-mail: cgonzalez.uaslp@gmail.com, E-mail: gonzalez.castillocarmen@fcq.uaslp.mx [Universidad Autonoma de San Luis Potosi, Facultad de Ciencias Quimicas (Mexico)

    2015-11-15

    The aim of this work was to compare the effects of 24-h exposure of rat primary astrocytes and C6 rat glioma cells to 7.8 nm AgNPs. Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor and current treatments lead to diverse side-effects; for this reason, it is imperative to investigate new approaches, including those alternatives provided by nanotechnology, like nanomaterials (NMs) such as silver nanoparticles. Herein, we found that C6 rat glioma cells, but no primary astrocytes, decreased cell viability after AgNPs treatment; however, both cell types diminished their proliferation. The decrease of glioma C6 cells proliferation was related with necrosis, while in primary astrocytes, the decreased proliferation was associated with the induction of apoptosis. The ionic control (AgNO{sub 3}) exerted a different profile than AgNPs; the bulk form did not modify the basal effect in each determination, whereas cisplatin, a well-known antitumoral drug used as a comparative control, promoted cytotoxicity in both cell types at specific concentrations. Our findings prompt the need to determine the fine molecular and cellular mechanisms involved in the differential biological responses to AgNPs in order to develop new tools or alternatives based on nanotechnology that may contribute to the understanding, impact and use of NMs in specific targets, like glioblastoma cells.

  10. S100B-p53 disengagement by pentamidine promotes apoptosis and inhibits cellular migration via aquaporin-4 and metalloproteinase-2 inhibition in C6 glioma cells.

    Science.gov (United States)

    Capoccia, Elena; Cirillo, Carla; Marchetto, Annalisa; Tiberi, Samanta; Sawikr, Youssef; Pesce, Marcella; D'Alessandro, Alessandra; Scuderi, Caterina; Sarnelli, Giovanni; Cuomo, Rosario; Steardo, Luca; Esposito, Giuseppe

    2015-06-01

    S100 calcium-binding protein B (S100B) is highly expressed in glioma cells and promotes cancer cell survival via inhibition of the p53 protein. In melanoma cells, this S100B-p53 interaction is known to be inhibited by pentamidine isethionate, an antiprotozoal agent. Thus, the aim of the present study was to evaluate the effect of pentamidine on rat C6 glioma cell proliferation, migration and apoptosis in vitro. The change in C6 cell proliferation following treatment with pentamidine was determined by performing a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide-formazan assay. Significant dose-dependent decreases in proliferation were observed at pentamidine concentrations of 0.05 µM (58.5±5%; Ppentamidine was associated with a significant increase in apoptosis versus the untreated cells, as determined by DNA fragmentation assays, immunofluorescence analysis of C6 chromatin using Hoechst staining, and immunoblot analysis of B-cell lymphoma-2 (Bcl-2)-associated X protein (100%, Ppentamidine significantly upregulated the protein expression levels of p53 (681±87.5%, Ppentamidine compared with untreated cells (88±4.2%, Ppentamidine and S100B-p53 inhibitors may represent a novel approach for the treatment of glioma.

  11. DAW22, a natural sesquiterpene coumarin isolated from Ferula ferulaeoides (Steud.) Korov. that induces C6 glioma cell apoptosis and endoplasmic reticulum (ER) stress.

    Science.gov (United States)

    Zhang, Lan; Tong, Xupeng; Zhang, Jin; Huang, Jian; Wang, Jinhui

    2015-06-01

    2,3-Dihydro-7-hydroxy-2R*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadienyl]-furo[3,2-c]coumarin (named DAW22), a sesquiterpene coumarin isolated from the roots of Ferula ferulaeoides (Steud.) Korov., has been reported to bear anti-proliferative activities toward different types of cancer cells. In this study, we demonstrated that DAW22 induced apoptosis in C6 glioma cells. Subsequently, we found that DAW22-induced apoptosis in C6 glioma cells occurred via the mitochondria-mediated and death-receptor pathways. Moreover, we found a massive cytoplasmic vacuolization, a dramatic change of endoplasmic reticulum (ER), up-regulation of CHOP and cleavage of caspase-12, suggesting that DAW22-induced apoptosis is involved in ER stress. In addition, we revealed that DAW22 treatment induced the activation of PERK, ATF6α and IRE1α. We further found that knockdown of CHOP affected DAW22-induced apoptosis, and DAW22-stimulated down-regulation of Bcl-2, caspase-8 activation and PARP cleavage were inhibited. Taken together, these results demonstrate that DAW22 induces apoptosis by ER stress and mitochondrial/death-receptor pathways, which may provide a new clue for exploiting this compound as a potential anti-neoplastic drug in future glioma cancer therapy.

  12. 突变型胸苷激酶对鼠C6胶质瘤细胞的杀伤效应%Killing effect of mutant herpes simplex virus type 1 thymidine kinase on rat C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    徐晓燕; 刘伟国; 杨小锋; 郑学胜; 沈罡

    2009-01-01

    Objective To explore the killing effect of mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39tk) and its wild type (HSV1-tk) on rat C6 glioma cells after Ganciclovir (GCV) treatment. Methods Eukaryotic expressing vector pcDNA3.1 containing HSV1-tk or HSV1-sr39tk was transfected into C6 cells and identified with RT-PCR. GCV killing efficiencies after gene transfer of HSV1-tk or HSV1-sr39tk were observed and compared in vitro and in vivo. Results 308bp DNA fragment was amplified through RT-PCR in both cells transfected with HSV1-tk (C6/tk) and those with HSV1-sr39tk (C6/sr39tk). As the prodrug GCV concentrations increasing from 0 μmol/L to 400 μmol/L, the cell survival rates in C6/sr39tk group declined from (99.96 ± 3.54) % to (4. 75 ± 1.79) %, while in C6/tk group from (100.03±2. 95)% to (59. 16±3.48)% and in C6 group from(100. 29±1.20)% to (83.62 ±7.56)%. There was a significant difference in killing effect among C6C6/tk and C6/sr39tk group after GCV treatment(P < 0. 05). In vivo experiment, the rate of tumor formation was 100%. After 10 day treatment of GCV following tumor formation, tumors in animals implantated with C6/sr39tk、C6/tk or C6 got an average volume equaling (574. 08±107.72) mm3、(928.47±165.61) mm3 and (1287.24±364. 84) mm3 respectively. The most powerful tumor growth inhibition was observed in C6/sr39tk + GCV group, with an inhibition rate of tumor growth about 55.40%. Conclusion C6 cells transfected with HSV1-sr39tk were more sensitive to GCV than those with HSV1-tk both in vitro and in vivo, and thus HSV1-sr39tk can be considered as a mean to improve the overall efficacy of the HSV1-tk/GCV suicide gene system.%目的 观察比较突变型单纯疱疹胸苷激酶(HSV1-sr39tk)/更昔洛韦(GCV)和野生型HSV1-tk/GCV对鼠C6胶质瘤细胞的杀伤效应.方法 利用真核表达载体转染目的 基因到C6细胞,RT-PCR鉴定.通过MTT实验和活体植瘤,比较各组对GCV敏感性.结果

  13. Exogenous hydrogen sulfide promotes C6 glioma cell growth through activation of the p38 MAPK/ERK1/2-COX-2 pathways.

    Science.gov (United States)

    Zhen, Yulan; Zhang, Wei; Liu, Chujie; He, Jing; Lu, Yun; Guo, Ruixian; Feng, Jianqiang; Zhang, Ying; Chen, Jingfu

    2015-11-01

    Hydrogen sulfide (H2S) participates in multifarious physiological and pathophysiologic progresses of cancer both in vitro and in vivo. We have previously demonstrated that exogenous H2S promoted liver cancer cells proliferation/anti‑apoptosis/angiogenesis/migration effects via amplifying the activation of NF-κB pathway. However, the effects of H2S on cancer cell proliferation and apoptosis are controversial and remain unclear in C6 glioma cells. The present study investigated the effects of exogenous H2S on cancer cells growth via activating p38 MAPK/ERK1/2-COX-2 pathways in C6 glioma cells. C6 glioma cells were treated with 400 µmol/l NaHS (a donor of H2S) for 24 h. The expression levels of phosphorylated (p)-p38 MAPK, total (t)-p38 MAPK, p-ERK1/2, t-ERK1/2, cyclooxygenase-2 (COX-2) and caspase-3 were measured by western blotting assay. Cell viability was detected by Cell Counting Kit-8 (CCK-8). Apoptotic cells were observed by Hoechst 33258 staining assay. Cell proliferation was directly detected under fully automatic inverted microscope. Exposure of C6 glioma cells to NaHS resulted in cell proliferation, as evidenced by an increase in cell viability. In addition, NaHS treatment reduced apoptosis, as indicated by the decreased apoptotic percentage and the cleaved caspase-3 expression. Importantly, exposure of the cells to NaHS increased the expression levels of p-p38 MAPK, p-ERK1/2 and COX-2. Notably, co-treatment of C6 glioma cells with 400 µmol/l NaHS and AOAA (an inhibitor of CBS) largely suppressed the above NaHS-induced effects. Combined treatment with NaHS and SB203580 (an inhibitor of p38 MAPK) or PD-98059 (an inhibitor of ERK1/2) resulted in the synergistic reduction of COX-2 expression and increase of caspase-3 expression, a decreased number of apoptotic cells, along with decreased cell viability. Combined treatment with NS-398 (an inhibitor of COX-2) and NaHS also resulted in the synergistic increase of caspase-3, a decreased in the

  14. Synthesis of dihydropyrimidin-2-one/thione library and cytotoxic activity against the human U138-MG and Rat C6 glioma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Canto, Romulo F.S.; Eifler-Lima, Vera Lucia [Universidade Federal do Rio Grande do Sul (LaSOM/PPGCF/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos Graduacao em Ciencias Farmaceuticas. Lab. de Sintese Organica; Bernardi, Andressa; Battastini, Ana Maria O. [Universidade Federal do Rio Grande do Sul (ICBS/UFRGS), Porto Alegre, RS (Brazil). Inst. de Ciencias Basicas da Saude; Russowsky, Dennis [Universidade Federal do Rio Grande do Sul (IQ/UFRGS), Porto Alegre, RS (Brazil). Inst. de Quimica

    2011-07-01

    Two series of 4-aryl-3,4-dihydropyrimidin-2(1H)-(thio)ones including monastrol (1a), have been synthesized by an environment-friendly methodology based on the combined use of citric acid or oxalic acid and TEOF (triethylorthoformate). The library was evaluated as inhibitor of cell proliferation on two glioma cell lines (human-U138-MG and Rat-C6). The compounds derived from thiourea 1f and 1d were more cytotoxic than monastrol. The compound derived from urea 2d showed the highest cytotoxic activity among the analyzed compounds. (author)

  15. Influence of physicochemical properties of laser-modified polystyrene on bovine serum albumin adsorption and rat C6 glioma cell behavior.

    Science.gov (United States)

    Wang, Xuefeng; Ohlin, C André; Lu, Qinghua; Hu, Jun

    2006-09-15

    Biomaterial surface modification is an efficient way of improving cell-material interactions. In this study, sub-micrometer laser-induced periodic surface structures (LIPSS) were produced on polystyrene by laser irradiation. FT-IR analysis confirmed that this treatment also led to surface oxidation and anisotropic orientation of the produced carbonyl groups. As a consequence, the surface energy of the laser-treated polystyrene was 1.45 times that of the untreated polystyrene, as measured by contact-angle goniometry. Protein adsorption and rat C6 glioma cell behavior on the two substrates were investigated, showing that the changed physicochemical properties of laser-modified polystyrene surface led to an increase in the quantity of adsorbed bovine serum albumin and significantly affected the behavior of rat C6 glioma cells. In the early stages of cell spreading, cells explored their microenvironment using filopodium as the main sensor. Moreover, cells actively aligned themselves along the direction of LIPSS gradually and cell attachment and proliferation were significantly enhanced.

  16. Tumor resection cavity administered iodine-131-labeled antitenascin 81C6 radioimmunotherapy in patients with malignant glioma: neuropathology aspects

    Energy Technology Data Exchange (ETDEWEB)

    McLendon, Roger E. [Department of Pathology, Duke University Medical Center, Durham, NC 27710 (United States)]. E-mail: mclen001@mc.duke.edu; Akabani, Gamal [Department of Radiology, Duke University Medical Center, Durham, NC 27710 (United States); Friedman, Henry S. [Department of Pediatrics, Duke University Medical Center, Durham, NC 27710 (United States); Reardon, David A. [Department of Medicine, Duke University Medical Center, Durham, NC 27710 (United States); Cleveland, Linda [Department of Pathology, Duke University Medical Center, Durham, NC 27710 (United States); Cokgor, Ilkcan [Department of Pediatrics, Duke University Medical Center, Durham, NC 27710 (United States); Herndon, James E. [Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710 (United States); Wikstrand, Carol [Department of Pathology, Duke University Medical Center, Durham, NC 27710 (United States); Boulton, Susan T. [Department of Surgery, Duke University Medical Center, Durham, NC 27710 (United States); Friedman, Allan H. [Department of Surgery, Duke University Medical Center, Durham, NC 27710 (United States); Bigner, Darell D. [Department of Pathology, Duke University Medical Center, Durham, NC 27710 (United States); Zalutsky, Michael R. [Department of Radiology, Duke University Medical Center, Durham, NC 27710 (United States)

    2007-05-15

    Introduction: The neurohistological findings in patients treated with targeted {beta} emitters such as {sup 131}I are poorly described. We report a histopathologic analysis from patients treated with combined external beam therapy and a brachytherapy consisting of a {sup 131}I-labeled monoclonal antibody (mAb) injected into surgically created resection cavities during brain tumor resections. Methods: Directed tissue samples of the cavity walls were obtained because of suspected tumor recurrence from 28 patients. Samples and clinical follow-up were evaluated on all patients (Group A) based on total radiation dose received and a subset of these (n=18; Group B, proximal therapy subset) who had received external beam therapy within {<=}3 months of mAb therapy and undergoing 26 biopsies over 37 months. Histologic outcomes were 'proliferative glioma,' 'quiescent glioma' and negative for neoplasm. Statistical analysis was used to assess the casual relation between total absorbed dose ({sup 131}I-mAb+external beam) and histologic diagnosis. Results: The lesions observed after {sup 131}I-mAb therapy were qualitatively similar to those reported for other types of radiation therapy; however, the high localized dose rate and absorbed doses produced by the short range of {sup 131}I {beta} particles seem to have resulted in an earlier necrotic reaction in the tumor bed. Among all 28 (Group A) patients, median survival from tissue analysis after mAb therapy depended on histopathology and total radiation absorbed dose. Median survival for patients with tissue classified as proliferative glioma, quiescent glioma and negative for neoplasm were 3.5, 15 and 27.5 months, respectively. Without categorization, total dose was a significant predictor of survival (P<.002) where patients with higher doses had better prognoses. For example, median survival in patients receiving a total radiation dose greater than 86 Gy was 19 months compared with 7 months for those

  17. Over-expression of Pygo2 Promotes C6 Cells Proliferation of Glioma%Pygo2过表达促进大鼠胶质瘤C6细胞增殖

    Institute of Scientific and Technical Information of China (English)

    陈玉英; 王海东; 王占祥; 谭国伟; 刘希尧; 沈上杭

    2012-01-01

    Objective To up-regulate expression of Pygopus2 (Fygo2) by construction of the recombinanl vectors of over-expression of Py-go2 protein,and to explore the role and mechanism of over-expression of Pygo2 in C6 cells proliferation of glioma. Methods The recombi-nant plasmids were digested with EcoR I and Hind III to execute the restriction endonuclease identification,then the sequence analysis was assayed by DNA sequencing. The recombinant plasmids were transfected into cultured gliohlastoma C6 cells using lipofectamineTM 2000. The exogenous Pygo2 protein level of C6 cells was detected by Western blot analysis. Colony framing assay and MTT assay were used to detect the cell proliferation,and cell cycle analysis was performed by flow cytometry analysis. The effect of Pygo2 over-expression on the level of cy-clinD1 and β-catenin of C6 cells was detected by Western blot analysis,and the expression and subcellular location of cyclinD1 and (3-catenin of C6 cells were further quantified by immunofluorescent staining. Results The recombinant plasmids were completely coincided with the designs by the restriction map and the sequence analysis,which up-regulated Pygo2 expression of C6 cells efficiently. After Pygo2 expression were up-regulated by transfected C6 cells with the recombinant plasmids,cells proliferation was promoted and colony forming was increased significantly,cell cycle progression from G, to S transition was enhanced notably. Furthermore,the expression level of cyclinD1 was significantly increased without change of subcellular location,and the expression level and subcellular location of β-catenin were not changed obviously. Concluson The recombinant vectors of Pygo2 over-expression were constructed successfully. Over-expression of Pygo2 promotes the growth of glioma cells by an increased expression of cyclinD1 to improve G1/S transition.%目的 通过构建过表达Pygo2的重组体上调Pygo2表达,探讨其在大鼠胶质瘤C6细胞增

  18. Regulation of cyclic GMP, cyclic amp and lactate dehydrogenase by putative neutrotransmitters in the C6 rat glioma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Bottenstein, J.E.; de Vellis, J.

    1977-01-01

    In C6 cells norepinephrine and dopamine caused transient increases in cyclic GMP and cyclic AMP, as well as an induction of lactate dehydrogenase. All of these responses were blocked by 1-propranolol, suggesting mediation by a ..beta..-receptor. Phentolamine potentiated the NE-increased cAMP levels by 5-fold when NE was used at suboptimal doses, suggesting the presence of ..cap alpha..-adrenergic receptors in C6 cells. Carbamylcholine decreased the levels of both cyclic nucleotides, with hexamethonium partially reversing the effect on cyclic GMP. Dibutyryl-cyclic GMP or carbamylcholine reduced catecholamine-induced cyclic AMP levels. Serotonin increased cyclic GMP levels 60% and decreased cyclic AMP levels 36%. Calcium- and magnesium-free media inhibited the norepinephrine-induced levels of cyclic GMP and cyclic AMP respectively.

  19. Regulation of cyclic GMP, cyclic AMP and lactate dehydrogenase by putative neurotransmitters in the C6 rat glioma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Bottenstein, J.E.; de Vellis, J.

    1978-01-01

    In C6 cells norepinephrine and dopamine caused transient increases in cyclic GMP and cyclic AMP, as well as an induction of lactate dehydrogenase. All of these responses were blocked by l-propranolol, suggesting mediation by a ..beta..-receptor. Phentolamine potentiated the NE-increased cAMP levels by 5-fold when NE was used at suboptimal doses, suggesting the presence of ..cap alpha..-adrenergic receptors in C6 cells. Carbamylcholine decreased the levels of both cyclic nucleotides, with hexamethonium partially reversing the effect on cyclic GMP. Dibutyryl-cyclic GMP or carbamylcholine reduced catecholamine-induced cyclic AMP levels. Serotonin increased cyclic GMP levels 60% and decreased cyclic AMP levels 36%. Calcium- and magnesium-free media inhibited the norepinephrine-induced levels of cyclic GMP and cyclic AMP respectively.

  20. Additivity, antagonism, and synergy in arsenic trioxide-induced growth inhibition of C6 glioma cells: effects of genistein, quercetin and buthionine-sulfoximine.

    Science.gov (United States)

    Klauser, Ellen; Gülden, Michael; Maser, Edmund; Seibert, Sabine; Seibert, Hasso

    2014-05-01

    Arsenic trioxide (ATO) induces clinical remission in acute promyelocytic leukemia and growth inhibition in various cancer cell lines in vitro. Recently, genistein and quercetin were reported to potentiate ATO-provoked apoptosis in leukemia and hepatocellular carcinoma cells. Genistein acted via enhanced ROS generation and quercetin via glutathione depletion. Searching for potential strategies for the treatment of malignant gliomas in this study the capacity of these flavonoids to sensitize rat C6 astroglioma cells for the cytotoxic action of ATO was investigated. ATO inhibited cell growth in a concentration- and time-dependent manner. This effect was accompanied neither by enhanced radical generation nor lipid peroxidation and was not attributed to apoptosis. ATO treatment concentration-dependently increased glutathione levels. Genistein enhanced radical generation. Combined with ATO it inhibited cell growth additively. Additivity was also obtained after cotreatment with ATO and H2O2. Quercetin acted antagonistically on ATO-induced growth inhibition. Quercetin increased glutathione levels. In contrast, buthionine-sulfoximine (BSO) depleted cellular glutathione and acted synergistically with ATO. In conclusion, in C6 cells neither genistein nor quercetin are suited as sensitizing agent, in contrast to BSO. Depletion of cellular glutathione content rather than an increase of ROS generation plays a central role in the enhancement of ATO-toxicity in C6 cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Wild Type p53 gene sensitizes rat C6 glioma cells to HSV-TK/ACV treatment in vitro and in vivo.

    Science.gov (United States)

    Huang, Qiang; Xia, Zhibo; You, Yongping; Pu, Peiyu

    2010-12-01

    Suicide gene therapy using herpes simplex virus-thymidine kinase (HSV-TK)/ganciclovir (GCV), has been extensively tested for the treatment of glioma. Our previous study showed that exogenous wild type p53 (wt-p53) enhanced the anti-tumor effect of HSV-TK/GCV therapy. However, the use of GCV is hindered by its low penetration to the brain and its toxicity when used at higher dose. In the present study, we used another pro-drug, acyclovir (ACV), and examined the therapeutic efficacy of HSV-TK/ACV combining with wt-p53 in C6 glioma cells. We observed that wt-p53 combined with HSV-TK/ACV resulted in the super-additive anti-tumor effect in vitro. Exogenous wt-p53 significantly enhanced the sensitivity of TK positive C6 cells to ACV in vitro. Our in vivo experiment demonstrated that the effect of wt-p53 and HSV-TK/ACV combination therapy was better than that of HSV-TK/ACV alone. The survival time of tumor-bearing rats treated with wt-p53 in combination with HSV-TK/ACV was also significantly prolonged than those treated with HSV-TK/ACV alone. These results suggest that wt-p53 can enhance the therapeutic efficacy of HSV-TK/ACV both in vitro and in vivo. These findings are considerably valuable with the respect of using less toxic ACV as prodrug. This novel strategy could provide benefit to HSV-TK/prodrug gene therapy.

  2. Efeito da epicatequina galato sobre parâmetros gliais na linhagem C6 de glioma de rato

    OpenAIRE

    Renata Torres Abib

    2008-01-01

    Hoje há um grande interesse em componentes da dieta, como os polifenóis do chá verde, os quais podem exercer efeitos de proteção contra várias doenças neurológicas, incluindo Alzheimer, isquemia e acidente vascular cerebral. O objetivo deste estudo foi investigar o efeito da (-) epicatequina 3-galato (ECG), um dos principais antioxidantes do chá verde, em células da linhagem C6. Avaliamos morfologia e integridade celular, captação de glutamato e secreção de S100B e o efeito sobre a genotoxici...

  3. Gliomas

    OpenAIRE

    Berger, M.; Weller, M.

    2016-01-01

    Key Features •Synthesizes widely dispersed information on the management of gliomas into one comprehensive resource •Chapters written by international authors who are preeminent researchers in the field •Fully explores the therapeutic options for patient care, from chemotherapy to radiotherapy to personalized approaches Description Researchers’ knowledge of gliomas continues to advance rapidly at both the basic and translational levels, and Gliomas provides a thorough overview ...

  4. 苦参碱对胶质瘤大鼠模型中Fas表达的调节作用的实验研究%Effect of mtrine on Fas expression in C6 glioma in rats

    Institute of Scientific and Technical Information of China (English)

    戚基萍; 刘微; 张淑君; 昝丽坤; 孙玉兰; 宋月佳

    2009-01-01

    目的 探讨苦参碱应用前后C6脑胶质瘤大鼠模型中Fas因子的表达变化及意义.方法采用脑立体定向技术,将体外培养的C6胶质瘤细胞注入大鼠尾状核区制备胶质瘤大鼠模型,并根据是否用药及用药量的多少分为空白对照组、冰片组、苦参碱低剂量组、苦参碱高剂量组、苦参碱低剂量+冰片组、苦参碱高剂量+冰片组.通过大鼠生存状态、标本的大体所见、MRI、HE染色观察苦参碱对胶质瘤大鼠模型生存质量及胶质瘤体积的影响,用免疫组织化学方法检测苦参碱对胶质瘤大鼠模型肿瘤细胞中Fas表达的影响.结果 大鼠生存状态、标本的大体所见、MRI及HE染色显示苦参碱可显著提高胶质瘤大鼠模型的生存质量,抑制胶质瘤细胞增殖.免疫组化结果显示,苦参碱低剂量+冰片组(98.16±11.82)、苦参碱高剂量+冰片组(1 12.80±12.12)Fas表达高于空白对照组(39.09±7.79)、冰片组(46.87±7.43)、苦参碱低剂量组(42.41±7.83)、苦参碱高剂量组(44.20±7.47),苦参碱高剂量+冰片组Fas表达高于苦参碱低剂量+冰片组,差异均有统计学意义(P<0.05).结论 苦参碱能增加胶质瘤细胞中Fas的表达,抑制胶质瘤细胞增殖.%Objective To investigate the effect of matrine on Fas expression in C6 glima in a tumor-bearing rat model. Methods Cultured cerebral glioma C6 cells wgre injected stereotactically into the lef tcaudate nucleus of the rats.The ratswere randomized into untreated group,bomeol-treated group,low-dose matrine group,high-dose maaine group,low-dose matrine+bomeol group,and high-dose matrine+borneol group.The effect of matrine on the quality of life of the rats and the glioma volume was evaluated according to the survival state of the rats and by gross observation,magnetic resonance imaging(MRJ)and HE smining of the brain tissue.Immunohistochemistry was performed to detect Fas expression in the glioma cells. Results The survival state

  5. Intracellular labeling and quantification process by magnetic resonance imaging using iron oxide magnetic nanoparticles in rat C6 glioma cell line; Marcacao intracelular e processo de quantificacao por imagem por ressonancia magnetica utilizando nanoparticulas magneticas de oxido de ferro em celulas da linhagem C6 de glioma de rato

    Energy Technology Data Exchange (ETDEWEB)

    Mamani, Javier Bustamante; Pavon, Lorena Favaro; Sibov, Tatiana Tais; Rossan, Fabiana; Silveira, Paulo Henrique; Cardenas, Walter Humberto; Gamarra, Lionel Fernel, E-mail: javierbm@einstein.br [Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Miyaki, Liza Aya Mabuchi [Faculdade de Enfermagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Amaro Junior, Edson [Departamento de Diagnostico por Imagem e Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil)

    2012-04-15

    Objective: To assess intracellular labeling and quantification by magnetic resonance imaging using iron oxide magnetic nanoparticles coated with biocompatible materials in rat C6 glioma cells in vitro. These methods will provide direction for future trials of tumor induction in vivo as well as possible magnetic hyperthermia applications. Methods: Aminosilane, dextran, polyvinyl alcohol, and starch-coated magnetic nanoparticles were used in the qualitative assessment of C6 cell labeling via light microscopy. The influence of the transfection agent poly-L-lysine on cellular uptake was examined. The quantification process was performed by relaxometry analysis in T{sub 1} and T{sub 2} weighted phantom images. Results: Light microscopy revealed that the aminosilane-coated magnetic nanoparticles alone or complexed with poly-L-lysine showed higher cellular uptake than did the uncoated magnetic particles. The relaxactivities of the aminosilane-coated magnetic nanoparticles with a hydrodynamic diameter of 50nm to a 3-T field were r{sub 1}=(6.1 +- 0.3) x10{sup -5} ms{sup -1}mL/{mu}g, r{sub 2}=(5.3 +- 0.1) x 10{sup -4} ms{sup -1}mL/{mu}g, with a ratio of r{sub 2} / r{sub 1}{approx_equal} 9. The iron uptake in the cells was calculated by analyzing the relaxation rates (R{sub 1}and R{sub 2}) using a mathematical relationship. Conclusions: C6 glioma cells have a high uptake efficiency for aminosilane-coated magnetic nanoparticles complexed with the transfection agent poly-L-lysine. The large ratio r{sub 2} / r{sub 1}{approx_equal} 9 indicates that these magnetic nanoparticles are ideal for quantification by magnetic resonance imaging with T{sub 2}-weighted imaging techniques. (author)

  6. Exposure of C6 glioma cells to Pb(II) increases the phosphorylation of p38{sup MAPK} and JNK1/2 but not of ERK1/2

    Energy Technology Data Exchange (ETDEWEB)

    Posser, Thais; Rossi, Francesco M.; Oliveira, Camila S.; Leal, Rodrigo B. [Universidade Federal de Santa Catarina, Departamento de Bioquimica, Centro de Ciencias Biologicas, Florianopolis, SC (Brazil); Mendes de Aguiar, Claudia B.N.; Garcez, Ricardo C.; Trentin, Andrea G. [Universidade Federal de Santa Catarina, Departamento de Biologia Celular, Embriologia e Genetica, Centro de Ciencias Biologicas, Florianopolis, SC (Brazil); Moura Neto, Vivaldo [Universidade Federal do Rio de Janeiro, Departamento de Anatomia, Centro de Ciencias da Saude, Rio de Janeiro, RJ (Brazil)

    2007-06-15

    Pb(II) is a neurotoxic pollutant that produces permanent cognitive deficits in children. Pb(II) can modulate cell signaling pathways and cell viability in a variety of cell types. However, these actions are not well demonstrated on glial cells, which represent an important target for metals into the central nervous system. The present work was undertaken to determine the ability of Pb(II) in modulating the activity of mitogen activated protein kinases (MAPKs) in cultures of C6 rat glioma cells, a useful functional model for the study of astrocytes. Additionally, cell viability was analyzed by measurement of MTT reduction. Cells were exposed to lead acetate 0.1, 1, 10 {mu}M for 24 and 48 h. MAPKs activation - in particular ERK1/2, p38{sup MAPK} and JNK1/2 - were analyzed by western blotting. Results showed that 10 {mu}M Pb(II) treatment for 24 h caused a discrete stimulation of p38{sup MAPK} phosphorylation. However, 1 and 10 {mu}M Pb(II) treatment for 48 h provoked a significant stimulation in the phosphorylation state of p38{sup MAPK} and JNK1/2. The phosphorylation state of ERK1/2 was not modified by any Pb(II) treatment. Moreover, data indicate that at 48 h treatment even 1 {mu}M Pb(II) can be cytotoxic, causing impairment on cell viability. Therefore, depending on a long incubation period, a significant concomitant activation of p38{sup MAPK} and JNK1/2 by Pb(II) took place in parallel with the impairment of C6 glioma cells viability. (orig.)

  7. Experimental study of magnetic resonance imaging and pathologies in rats with C6 gliomas after cryotherapy%氩氦冷冻治疗后的荷C6胶质瘤大鼠的磁共振成像和病理研究

    Institute of Scientific and Technical Information of China (English)

    李明; 黄凡衡; 胡丽娟; 周媛; 姜晓丹; 常海刚; 卢凤飞; 陈强; 张世忠

    2010-01-01

    目的 探讨荷C6胶质瘤大鼠经氩氦刀治疗后的影像学和病理学的变化. 方法 将51只Wistar大鼠背部皮下植入体外扩增的C6胶质瘤细胞,制作荷C6胶质瘤的动物模型,模型制作成功后按照随机数字表法分为假手术组(暴露肿瘤后只插入冷冻刀头不启动氩氦冷冻系统,n=18),外科手术切除组(将肿瘤完整切除,不进行冷冻操作,n=15)和氩氦冷冻组(暴露肿瘤后启动氩氦冷冻系统,n=18).观察各组大鼠治疗前后MRI影像变化,应用Tunel检测细胞凋亡情况.结果 外科手术成功切除胶质瘤.氩氦冷冻组MRI显示T1、W1信号较术前增强,T2WI信号较术前减低假手术组治疗后MRI无明显变化.氩氦冷冻组肿瘤组织Tunel染色可见大量凋亡细胞,外科手术切除组及假手术组可见少量散在的凋亡细胞.结论 经氩氦刀治疗胶质瘤MRI提示肿瘤细胞变性坏死,病理学提示可以介导细胞凋亡,有望成为脑胶质瘤的一种有效的辅助治疗手段.%Objective To explore the changes of imaging and pathologies in rots with bearing C6 gliomas after cryotherapy. Methods Animal models with subcutaneously transplanting C6 gliomas in the Wistar rates were established. Fifty-one rat models were randomized into sham-operated group (n=18), resection group (n=lS) and cryotherapy group (n=18). The tumors in the sham-operated group were exposed only and the tumors in the resection group were resected without the help of freezing system; the tumors in the cryotherapy group were performed argon-helium cryoablation. The changes of morphology and imaging were observed. TUNEL staining was employed to observe the cell apoptosis in the tumors. Results The tumors in the resection group were removed successfully by microsurgical resection. Cryotherapy group showed significantly enhanced T1WI signal and weak T2W1 signal after the treatment as compared with that before the treatment; no obvious difference of the MRI data was found

  8. Lipid-albumin nanoassemblies co-loaded with borneol and paclitaxel for intracellular drug delivery to C6 glioma cells with P-gp inhibition and its tumor targeting

    Directory of Open Access Journals (Sweden)

    Bo Tang

    2015-10-01

    Full Text Available Successful chemotherapy with paclitaxel (PTX is impeded by multidrug resistance (MDR in tumor cells. In this study, lipid-albumin nanoassemblies co-loaded with borneol and paclitaxel (BOR/PTX LANs were prepared to circumvent MDR in C6 glioma cells. The physiochemical properties including particle size, encapsulation efficiency and morphology were evaluated in vitro. Quantitative and qualitative investigations of cellular uptake were carried out in C6 glioma cells. The cytotoxicity of the BOR/PTX LANs was determined by MTT assay. After that, the tumor targeting was also evaluated in C6 glioma bearing mice by in vivo imaging analysis. BOR/PTX LANs have a higher entrapment efficiency (90.4 ± 1.2%, small particle size (107.5 ± 3.2 nm, narrow distribution (P.I. = 0.171 ± 0.02. The cellular uptake of PTX was significantly increased by BOR/PTX LANs compared with paclitaxel loaded lipid-albumin nanoassemblies (PTX LANs in quantitative research. The result was further confirmed by confocal laser scanning microscopy qualitatively. The cellular uptake was energy-, time- and concentration-dependent, and clathrin- and endosome/lysosome-associated pathways were involved. The BOR/PTX LANs displayed a higher cytotoxicity agaist C6 glioma cells in comparion with PTX LANs and Taxol. Moreover, the encapsulation of BOR in LANs obviously increased the accumulation of the drug in tumor tissues, demonstrating the tumor targeted ability of BOR/PTX LANs. These results indicated that BOR/PTX LANs could overcome MDR by combination of drug delivery systems and P-gp inhibition, and shown the potential for treatment of gliomas.

  9. 携带CD基因骨髓间充质干细胞对C6大鼠胶质瘤体内抑制作用研究%Investigation on The Inhibition Effects of Bone Marrow Mesenchymal Stem Cells With CD Gene on Glioma in C6 Rat

    Institute of Scientific and Technical Information of China (English)

    宋飞; 邢琪; 宋克东; 刘健; 姬广春; 马郁芳; 刘天庆; 马学虎; 田晓峰

    2012-01-01

    The in vivo treatment effect of CD (cytosine deaminase) suicidal genetic system on the glioma in rat was explored. The lentivirus carrier which was composed of CD genes was fabricated and the mouse BMMSCs were transfected by such CD genes to obtain constantly expressed cells, then BMMSCs were transplanted into the animal model which was built through an intracranial stereotactic inoculating method using a group of 40 SD rats. The rats were divided into 5 groups uniformly according to the cell type inoculated, i.e. ① C6 glioma, ②C6 + MSCs(mesenchymal stems cells) cells (1 : 1), ③C6+MSC cells (1 : 2), ④C6+MSC -codA/eGFP cells (1 : 1) and ⑤C6+MSC-codA/eGFP ce))s (1 : 2). After 7 days of tumor formation, the abdominal cavity of rats were injected with 5-FC at 500 mg/(kg· d) for 14 days. Intensive scanning was carried out weekly to observe tumor volume using MR1. Simultaneously, survival times, routine pathological test, RT-PCR assay and HE staining were also operated. The results of MRI showed that the focus of infection in group ① presented round shape. The necrosis area of tumor found in the center, achieved an average volume of 246 mm3, and the survival time of the center area was 15.3 days. About the group ② and ③, the survival times were 16.0 and 16.6 days respectively. But in group ④ and ⑤, the survival times were both larger than 30 days, the necrosis area of tumor was 55 and 40 mm3 respectively at day 14, and the inhibition efficiency was 77.24% and 83.28% respectively after 28 days of treatment. It was concluded that the MRI scanning could clearly show the volume, shape, and internal structure of the tumor, which was highly related to the results of pathology. The treatment effect of bone marrow MSCs with CD genes and 5-FC therapy system on C6 intracranial glioma could be verified through dynamic MRI observation. Moreover, the RT-PCR test confirmed the exptession of cytosine deaminase inside tumor organization.%为了研究自杀基因—

  10. 牛蒡子苷元对大鼠脑胶质瘤的作用及初步作用机制探讨%Effects and primary mechanism of arctigenin in C6 rat glioma

    Institute of Scientific and Technical Information of China (English)

    苏勤勇; 李晓梅; 姚景春; 王平平; 张贵民

    2015-01-01

    Aim To observe the effect and primary mechanism of arctigenin ( ARG) in C6 rat glioma. At the same time, to investigate the effect of ARG com-bined with temozolomide. Methods C6 glioma rat model was established, and 90 rats were divided into six groups, which were subcutaneously administered with model, low and high ARG (0. 05 and 0. 1 mg· kg-1 , sc) , temozolomide (20 mg·kg-1 , p. o. ) , low ARG combined with temozolomide(TMZ / ARG 0. 05) and high ARG combined with temozolomide ( TMZ /ARG 0. 1 ) . The tumor specimens of brain were col-lected after tumor graft. Proliferating cell nuclear anti-gen ( PCNA ) , glial fibrillary acidic protein ( GFAP ) and CD40 in tumor specimens were determined by im-munohistochemistry. Results ① Compared with the model group, the tumor sizes of rats in the arctigenin treatment groups were decreased ( P significantly decreased PCNA and CD40 expression ( P<0. 05 ) and increased GFAP expression ( P<0. 05 ) .③ Compared with model group, arctigenin combined with temozolomide decreased the tumor sizes ( P <0. 01 ) , and the tumor inhibition rate was higher than that of the arctigenin and temozolomide. At the same time, arctigenin combined with temozolomide de-creased PCNA and CD40 expression ( P <0. 01 ) and increased GFAP expression ( P <0. 05 ) , which was better than arctigenin and temozolomide. Conclusion Arctigenin inhibits rat glioma growth, and synergizes with temozolomide, which may be associated with in-hibiting PCNA and CD40 expression and strengthening GFAP expression.%目的:观察牛蒡子苷元对大鼠C6胶质瘤的作用及作用机制的研究。同时探讨牛蒡子苷元与替莫唑胺合用对脑胶质瘤是否有协同作用。方法采用脑内注射C6胶质瘤细胞建立大鼠C6胶质瘤模型;牛蒡子苷元连续皮下给药15 d,替莫唑胺从d5开始给药,连续灌胃给药5 d;测量肿瘤的长短径,计算肿瘤体积;采用免疫组化方法检测脑瘤组织中GFAP、PCNA和CD40的表达。结

  11. Activation of a pro-survival pathway IL-6/JAK2/STAT3 contributes to glial fibrillary acidic protein induction during the cholera toxin-induced differentiation of C6 malignant glioma cells.

    Science.gov (United States)

    Shu, Minfeng; Zhou, Yuxi; Zhu, Wenbo; Wu, Sihan; Zheng, Xiaoke; Yan, Guangmei

    2011-06-01

    Differentiation-inducing therapy has been proposed to be a novel potential approach to treat malignant gliomas. Glial fibrillary acidic protein (GFAP) is a well-known specific astrocyte biomarker and acts as a tumor suppressor gene (TSG) in glioma pathogenesis. Previously we reported that a traditional biotoxin cholera toxin could induce malignant glioma cell differentiation characterized by morphologic changes and dramatic GFAP expression. However, the molecular mechanisms underlying GFAP induction are still largely unknown. Here we demonstrate that an oncogenic pathway interleukin-6/janus kinase-2/signal transducer and activator of transcription 3 (IL-6/JAK2/STAT3) cascade mediates the cholera toxin-induced GFAP expression. Cholera toxin dramatically stimulated GFAP expression at the transcriptional level in C6 glioma cells. Meanwhile, phosphorylation of STAT3 and JAK2 was highly induced in a time-dependent manner after cholera toxin incubation, whereas no changes of STAT3 and JAK2 were observed. Furthermore, the IL-6 gene was quickly induced by cholera toxin and subsequent IL-6 protein secretion was stimulated. Importantly, exogenous recombinant rat IL-6 can also induce phosphorylation of STAT3 concomitant with GFAP expression while JAK2 specific inhibitor AG490 could effectively block both cholera toxin- and IL-6-induced GFAP expression. Given that the methylation of the STAT3 binding element can suppress GFAP expression, we detected the methylation status of the critical recognition sequence of STAT3 in the promoter of GFAP gene (-1518 ∼ -1510) and found that it was unmethylated in C6 glioma cells. In addition, neither DNA methyltransferase1 (DNMT1) inhibitor 5-Aza-2'-deoxycytidine (5-AZa-CdR) nor silencing DNMT1 can stimulate GFAP expression, indicating that the loss of GFAP expression in C6 cells is not caused by its promoter hypermethylation. Taken together, our findings suggest that activation of a pro-survival IL-6/JAK2/STAT3 cascade contributes to

  12. Influence of serum and albumin on the in vitro anandamide cytotoxicity toward C6 glioma cells assessed by the MTT cell viability assay: implications for the methodology of the MTT tests.

    Science.gov (United States)

    Bilmin, Krzysztof; Kopczyńska, Beata; Grieb, Paweł

    2013-01-01

    Anandamide (AEA), an endogenous ligand of cannabinoid CB1 and CB2 receptors, which also binds transient receptor potential vanilloid type 1 receptor (TRPV1), has been shown to display substantial selective cytotoxicity toward some cancer cell lines in vitro, although the relevant data are not consistent. In the present study, we employed the MTT test to assess short-term cytotoxicity of AEA on C6 rat glioma cell culture. When anandamide was administered to the culture medium with foetal bovine serum (FBS), no cytotoxic effect was observed following 24 h exposure of the glioma cells to micromolar concentrations of AEA. However, if no serum was present in the medium, micro-to-submicromolar concentrations of AEA induced dose-dependent cytotoxicity clearly detectable after 24 h. Control experiments made it possible to exclude significant interference of serum with the MTT test per se. Bovine serum albumin mimicked the effect of FBS. We conclude that the apparent inhibition of short-term cytotoxicity of AEA toward C6 rat glioma cells in vitro is caused by binding AEA to serum proteins such as albumin. Taking into account that blood serum or albumin is practically always present in cell culture media, we discuss implications of binding substances to serum proteins for methodology and interpretation of in vitro cytotoxicity testing.

  13. 聚乙烯亚胺介导BmkCT基因抑制C6胶质瘤细胞C-Myc、VEGF表达%Expression of Polyethyleneimine-mediated Bmk CT Gene Inhibitation to VEGF and C-Myc in C6 Glioma Cells

    Institute of Scientific and Technical Information of China (English)

    张亚涛; 范丽娜; 温春丽; 胡风云

    2016-01-01

    目的:应用阳离子聚合物聚乙烯亚胺(polyethyleneimine,PEI)介导东亚钳蝎氯离子通道毒素( Buthus martensii Karsch Chlorotoxin-like Toxin,Bmk CT)基因转染 C6胶质瘤细胞,观察其对 C6细胞内 C-Myc、VEGF 表达的影响。方法:将 PEI 分别和 pEGFP-N1-Bmk CT、pEGFP-N1质粒混合,获得 PEI / pEGFP-N1-Bmk CT 和 PEI / pEG-FP-N1两种复合物,将其转染 C6细胞,MTS 法观察细胞增殖和存活活力,48 h后通过 Western-blot 方法检测 C-Myc、VEGF 蛋白表达水平。结果:PEI / pEGFP-N1-Bmk CT 转染 C6细胞48 h后较 PEI / pEGFP-N1能够显著抑制C6细胞增殖和存活活力,同时抑制 C-Myc、VEGF 蛋白表达。结论:PEI / pEGFP-N1-Bmk CT 转染 C6细胞可能通过抑制 C-Myc、VEGF 表达进而抑制 C6细胞增殖和血管生成。%Objective:To investigate the effects of PEI(polyethyleneimine)-mediated Bmk CT(Buthus martensii Karsch Chlorotoxin-like Toxin),Bmk CT gene transfection on the expression levels of C-Myc and VEGF of C6 glioma cells. Methods:pEGFP-N1 and pEGFP-N1-BmK CT were combined with PEI to form the composites,PEI/ pEGFP-N1-Bmk CT and PEI/ pEGFP-N1,which were used to transfect C6 glioma cells. Then,MTS test was performed to investigate the proliferation and viability of the transfected cells. After 48 hours the expression of C-Myc and VEGF proteins were de-tected by Western-bloting. Results:The proliferation of C6 glioma cells in the pEGFP-N1-Bmk CT group was significant-ly inhibited,while the expression levels of C-Myc and VEGF were lower than pEGFP-N1 group after the transfection. Conclusion:PEI/ pEGFP-N1-Bmk CT may suppress the angiogenesis and the proliferation of C6 glioma cells through in-hibiting the expression of C-Myc and VEGF.

  14. Modifications of the fiber in adenovirus vectors increase tropism for malignant glioma models.

    Science.gov (United States)

    Staba, M J; Wickham, T J; Kovesdi, I; Hallahan, D E

    2000-01-01

    Recombinant adenovirus (Ad) vectors provide a means of local, therapeutic gene delivery to a wide range of neoplasms. Ad-mediated gene therapy trials in malignant glioma models have been limited by the need for high viral titers and multiple dosages. In an attempt to improve Ad vector gene transfer, we studied human (U87, D54) and rodent (GL261, C6) malignant glioma cell lines transfected with various doses of unmodified Ad vectors (AdZ), Ad vectors that contain an alteration of the fiber-coat protein and that direct virus binding to heparan sulfate receptors (AdZ.F(pK7)), and Ad vectors with modifications of the fiber-coat protein that direct virus binding to alpha1, integrin cellular receptors (AdZ.F(RGD)). AdZ.F(pK7) increased the frequency of cells expressing the reporter gene, beta-galactosidase, and improved transduction by 2- to 20-fold compared with AdZ in U87, D54, and GL261 cells. In U87, D54, GL261, and C6 tumors, AdZ.F(pK7) increased gene transfer by 10- to 100-fold compared with AdZ. AdZ.F(RGD) increased gene expression in C6 xenografts compared with AdZ, but had reduced transduction compared with the C6 xenografts of AdZ in all other glioma tumors. These findings suggest that the increased tropisms resulting from alterations of the Ad vector fiber-coat protein as in AdZ.F(pK7) and AdZ.F(RGD) offer a feasible approach to improving in vitro and in vivo transduction efficiencies in certain malignant glioma cell lines.

  15. Oxygen chemisorption on Cu(110): A model for the c(6×2) structure

    DEFF Research Database (Denmark)

    Feidenhans'l, Robert Krarup; Grey, Francois; Nielsen, Mourits

    1990-01-01

    From an interplay between scanning tunneling microscopy, surface x-ray-diffraction experiments, and theoretical predictions, an unequivocal structural model for the Cu(110)-c(6×2)O surface reconstruction is derived with ten Cu atoms within the c(6×2) unit cell, two of which form a Cu superstructure....... A general picture evolves in which the present as well as the Cu(110)-(2×1)O and the Cu(100)-(2 √2 × √2 )R45°O reconstructions are stabilized by Cu-O-Cu chains directed along the [001] direction. The nucleation and growth of the c(6×2) structure occur preferentially at steps....

  16. 替莫唑胺诱导大鼠脑胶质瘤C6细胞caspase非依赖的程序性死亡%Caspase-independent programmed cell death induced by temozolomide in rat glioma C6 cell line

    Institute of Scientific and Technical Information of China (English)

    刘丽华; 张明

    2015-01-01

    Objective To investigate programmed cell death induced by temozolomide in rat glioma C6 cell line. Methods Rat glioma C6 cell line was treated by temozolomide at different concentrations and for different time lengths. MTT assay was used to evaluate the cell inhibition rate to determine the optimal exposure time and concentration. After the exposure to 400μg/ml temozolomide for 24 h, the cells were observed for programmed cell death using HE staining, Hochest and Tunnel assay, Western blotting, and immunohistochemistry. Results MTT, HE staining, and Hochest and Tunnel assay all showed temozolomide-induced apoptosis in rat glioma C6 cell line. Western blotting and immunohistochemistry revealed up-regulation of Bax and down-regulation of Bcl-2 expression in the exposed cells, where the expressions of caspases 3, 8, 9, and 12 remained unchanged. Conclusion Temozolomide induces apoptosis in rat glioma C6 cell line through a caspase-independent pathway.%目的:观察替莫唑胺对大鼠脑胶质瘤C6细胞程序性死亡的诱导效应,并探讨可能的分子机制。方法观察不同浓度替莫唑胺在不同时间点处理大鼠脑胶质瘤大鼠脑胶质瘤C6细胞系,MTT法观察抑制率并筛选出最优的作用时间和作用浓度。应用400μg/ml替莫唑胺处理细胞24 h,通过HE染色、Hochest、Western blot、Tunnel、免疫组化观察替莫唑胺对大鼠脑胶质瘤C6细胞系的程序性死亡的诱导效应。结果 MTT法、HE染色、Hochest和Tunnel结果显示替莫唑胺对大鼠脑胶质瘤C6细胞具有凋亡诱导效应;免疫组化和Western blot结果显示促凋亡蛋白Bax表达水平上调,凋亡抑制蛋白Bcl-2表达的下调。未发现主要的caspase蛋白的表达变化。结论替莫唑胺对脑胶质瘤C6细胞具有凋亡诱导效应,而这种效应可能是通过caspase非依赖途径完成的。

  17. Synergistic effects of cryotherapy and rhTNFα in the treatment of C6 brain glioma%冷冻和rhTNF-α对C6大鼠脑胶质瘤的联合治疗作用

    Institute of Scientific and Technical Information of China (English)

    黄宽明; 冯艳琴; 王伦长; 涂汉军; 李新建; 易建华

    2006-01-01

    目的:探讨冷冻联合rhTNF-α治疗C6大鼠脑胶质瘤的可行性.方法:借助于立体定位技术,将C6胶质瘤细胞接种于80只雄性Wistar大鼠脑S1区,待肿瘤长至第15天,直径约6 mm时,随机将荷瘤鼠分为4组:G1、G2、G3、G4分别为生理盐水对照组、冷冻治疗组、rhTNF-α治疗组及联合治疗组,每组20只,分别行相应的治疗.治疗后第15天,采用免疫组化检测PCNA的表达;行核磁共振(MRI)检查,测量肿瘤体积和抑瘤率.动态观察各组荷瘤鼠生存期和rhTNF-α对荷瘤鼠的毒副作用.结果:联合治疗组PCNA的表达情况、肿瘤体积和生存期与其他各组相比有显著差异,且该组对肿瘤生长的抑制率(89.48%)明显高于冷冻组(66.31%)和TNF-α组(49.01%),且大于理论抑瘤率(82.82%).同时观察到rhTNF-α对实验动物有一定毒副作用.结论:冷冻和rhTNF-α联合应用,具有协同抗肿瘤作用,为进一步临床研究提供了实验依据.

  18. Blockage of Autophagy in C6 Glioma Cells Enhanced Radiosensitivity Possibly by Attenuating DNA-PK-Dependent DSB Due to Limited Ku Nuclear Translocation and DNA Binding.

    Science.gov (United States)

    Liu, C; He, W; Jin, M; Li, H; Xu, H; Liu, H; Yang, K; Zhang, T; Wu, G; Ren, J

    2015-01-01

    Glioblastoma multiforme (GBM) is the most lethal brain tumor and notorious for its resistance to ionizing radiation (IR). Recent evidence suggests that one possible mechanism that enables resistance to IR and protects cells against therapeutic stress is cellular autophagy. The molecular basis for this pro-survival function, however, remains elusive. Herein, we report a molecular mechanism by which IR-induced autophagy accelerates the repair of DNA double-strand breaks (DSB). We demonstrate that IR induces the accumulation of autophagosomes, which is accompanied by elevated expression of autophagyrelated genes beclin-1, atg5, atg7, and atg12. Beclin-1 knockdown impaired the induction of IR-mediated autophagy and significantly sensitized glioma cells to radiation therapy in vitro and in vivo. Furthermore, our data is the first to demonstrate that the radiosensitizing effect of beclin-1 knockdown may result from the disruption of nuclear translocation and DNA binding activity of Ku proteins and consequent attenuation of DSB repair. Our findings help advance our understanding of the molecular mechanisms underlying IR-induced autophagy and provide a promising adjunctive therapeutic strategy for the radiosensitization of malignant glioma.

  19. Growth Inhibiting and Apoptosis-inducing Effects of the Aqueous Extract of Albizia julibrissin Durazz Flower on Rat Glioma Cells C6%合欢花水提物对大鼠脑胶质瘤C6细胞株的增殖抑制与凋亡诱导作用

    Institute of Scientific and Technical Information of China (English)

    昝亚伟; 张立伟; 陈廷贵

    2012-01-01

    采用MTT法检测合欢花水提物对C6细胞增殖活力的影响,流式细胞术检测该水提物对C6细胞的诱导凋亡作用.结果表明:合欢花水提物能抑制C6细胞的增殖,且具有剂量和时间依赖性,其在24 h、48 h、72 h时对C6细胞的半数抑制率(LD50)分别为:305 μg/mL、50 μg/mL、15 μg/mL.流式细胞术结果显示:200 tμg/mL、300μg/mL合欢花水提物均可诱导C6细胞发生早期凋亡,与对照组细胞相比,早期凋亡率分别由对照组的0.7%增加到了4.3%、14.3%.提示合欢花水提物抑制C6细胞增殖机理与诱导细胞凋亡途径有关.%The growth inhibiting and apotosis-inducing effects of aqueous extract of Albizia julibrissin Durazz flower(AJDF) on the rat glioma cells C6 in vitro were studied by MTT assays and flow cytometry methods. The results showed that the water extract of AJDF had obvious suppression on the proliferation of C6 cell lines,which had significant dose-and time-dependent relationships.the LD50 was respectively 305 μg/mL.50 μg/mL,15 μg/mL for 24 h,48 h.72 h. The flow cytometric analysis displayed that 200 μg/mL,300 μg/mL water extract of AJDF can both induce C6 cell lines early phase apotosis.apotosis rate was respectively 4. 3% .14. 3% ,but the blank control group was only 0. 7%. The mechanisim of inhibiting proliferation might be related to cell apoptosis.

  20. 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure influence the expression of glutamate transporter GLT-1 in C6 glioma cells via the Ca(2+) /protein kinase C pathway.

    Science.gov (United States)

    Zhao, Jianya; Zhang, Yan; Zhao, Jianmei; Wang, Cheng; Mao, Jiamin; Li, Ting; Wang, Xiaoke; Nie, Xiaoke; Jiang, Shengyang; Wu, Qiyun

    2016-11-01

    The widespread environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), is considered one of the most toxic dioxin-like compounds. Although epidemiological studies have shown that TCDD exposure is linked to some neurological and neurophysiological disorders, the underlying mechanism of TCDD-mediated neurotoxicity has remained unclear. Astrocytes are the most abundant cells in the nervous systems, and are recognized as the important mediators of normal brain functions as well as neurological, neurodevelopmental and neurodegenerative brain diseases. In this study, we investigated the role of TCDD in regulating the expression of glutamate transporter GLT-1 in astrocytes. TCDD, at concentrations of 0.1-100 nm, had no significantly harmful effect on the viability of C6 glioma cells. However, the expression of GLT-1 in C6 glioma cells was downregulated in a dose- and time-dependent manner. TCDD also caused activation of protein kinase C (PKC), as TCDD induced translocation of the PKC from the cytoplasm or perinuclear to the membrane. The translocation of PKC was inhibited by one Ca(2+) blocker, nifedipine, suggesting that the effects are triggered by the initial elevated intracellular concentration of free Ca(2+) . Finally, we showed that inhibition of the PKC activity reverses the TCDD-triggered reduction of GLT-1. In summary, our results suggested that TCDD exposure could downregulate the expression of GLT-1 in C6 via Ca(2+) /PKC pathway. The downregulation of GLT-1 might participate in TCDD-mediated neurotoxicity. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Gamma Knife Radation Induce C6 Glioma Cell Apoptosis and Change of Oncegene c-myc、P16%伽玛刀照射诱导C6脑胶质瘤凋亡及其癌基因c-myc、P16蛋白表达的变化

    Institute of Scientific and Technical Information of China (English)

    綦斌; 王建光; 田宇; 周建

    2001-01-01

    Objective To investigate the apoptosis of C6 glioma cell and the change of c-myc and P16 gene's protein expression after Gamma knife radiation.Methods Electron microscope shows apoptosis cells of culture rat C6 maligant glioma after Gamma knife radiation,immunhistochemistry technique(SP method) is employed to inspect the change of c-myc and P16 gene's protein.Results A small dosage γ-radiation can induce apoptosis,a big dosage results in necrosis,c-myc and p16 gene's expression in treatment group is higher than that in control group (P<0.05).Conclusions Cellular proto-once gene c-myc and tumor suppesser gene P16 are important in radiation-induced apoptosis.%目的 探讨伽玛刀照射诱导C6脑胶质瘤细胞凋亡及其相关癌基因变化。方法 C6脑胶质瘤细胞经伽玛刀照射后光镜及电镜下观察细胞凋亡,采用免疫组化技术检测原癌基因c-myc、抑癌基因P16蛋白表达的变化。结果 小剂量γ射线可诱导瘤细胞凋亡,而大剂量γ射线引起细胞坏死,处理组c-myc、P16基因在蛋白水平表达率明显高于对照组(P<0.05)。结论 原癌基因c-myc、抑癌基因P16在辐射诱导凋亡中起重要作用。本研究为临床放疗方案的优化、减轻放疗的副作用等提供参考。

  2. Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells—Characterization of a New in Vivo Model

    Directory of Open Access Journals (Sweden)

    Sonja Stojković

    2016-06-01

    Full Text Available Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl-1-nitrosourea (BCNU and temozolomide (TMZ. Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells’ invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats’ behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells.

  3. Effects of Photodynamic Therapy on the Ultrastructure of Glioma Cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To study the change in ultrastructure of C6 glioma cells after photodynamic therapy (PDT), to compare morphological differences in necrosis and apoptosis before and after PDT treatment, and to evaluate the effect of photodynamic therapy on the blood brain tumor barrier (BTB) of C6 glioma. Methods The model was produced by transplanting C6 glioma cells cultured in vitro using Peterson method into the caudate nuclei of Wister rats. The experiment group received PDT for two weeks after the operation. The sub-cellular structure, blood-brain-barrier (BBB) and BTB in both groups were observed under electron microscope. Results Apoptosis in different phases and necrosis could be observed in some C6 glioma cells.Swelling occurred on the ultrastructure of cellular organs such as mitochondria and endoplasmic reticulum in most of the cells.Damage to the BTB, reduction of the number of cellular organs in endothelial cells of the capillary blood vessels, stretch of the tight junction, and enlargement of the gaps between endothelial cells were also seen in the experiment group. Meanwhile,limited impact on the normal sub-cellular structures and BBB was observed. Conclusion PDT could induce apoptosis and necrosis of C6 glioma cells due to the damage to the ultrastructure of mitochondria and endoplasmic reticulum. The weakened function of C6 glioma BTB initiated by PDT makes it possible to perform a combined therapy of PDT and chemotherapy for glioma.

  4. Establishment of intramedullary spinal cord glioma model in rats

    Institute of Scientific and Technical Information of China (English)

    REN Tian-jian; WANG Zhong-cheng; ZHANG Ya-zhuo; LI Dan; WANG Hong-yun; LI Zhen-zong

    2010-01-01

    Background Treating intramedullary spinal cord gliomas is a big challenge because of limited options, high recurrence rate and poor prognosis. An intramedullary glioma model is prerequisite for testing new treatments. This paper describes the establishment of a rodent intramedullary glioma model and presents functional progression, neuroimaging and histopathological characterization of the tumour model.Methods Fischer344 rats (n=24) were randomized into two groups. Group 1 (n=16) received a 5 μl intramedullary implantation of 9L gliosarcomal (105) cells. Group 2 (n=8) received a 5 μl intramedullary injection of Dulbecco's modified Eagle medium. The rats were anesthetized, the spinous process of the T10 vertebra and the ligamentum flavum were removed to expose the T10-11 intervertebral space and an intramedullary injection was conducted into the spinal cord. The rats were evaluated preoperatively and daily postoperatively for neurological deficits using the Basso, Beattie and Bresnahan scale. High resolution magnetic resonance images were acquired preoperatively and weekly postoperatively.When score equal to 0, rats were sacrificed for histopathological examination.Results Rats implanted with 9L gliosarcoma cells had a statistically significant median onset of hind limb paraplegia at (16.0±0.4) days, compared with rats in the control group in which neurological deficits were absent. Imaging and pathological cross sections confirmed intramedullary 9L gliosarcoma invading the spinal cord. Rats in the control group showed no significant functional, radiological or histopathological findings of tumour.Conclusions Rats implanted with 9L cells regularly develop paraplegia in a reliable and reproducible manner. The progression of neurological deficits, neuroimaging and histopathological characteristics of intramedullary spinal cord gliomas in rats is comparable with the behaviour of infiltrative intramedullary spinal cord gliomas in patients.

  5. A human brainstem glioma xenograft model enabled for bioluminescence imaging

    OpenAIRE

    Hashizume, Rintaro; Ozawa, Tomoko; Dinca, Eduard B.; Banerjee, Anuradha; Prados, Michael D.; James, Charles D.; Gupta, Nalin

    2009-01-01

    Despite the use of radiation and chemotherapy, the prognosis for children with diffuse brainstem gliomas is extremely poor. There is a need for relevant brainstem tumor models that can be used to test new therapeutic agents and delivery systems in pre-clinical studies. We report the development of a brainstem-tumor model in rats and the application of bioluminescence imaging (BLI) for monitoring tumor growth and response to therapy as part of this model. Luciferase-modified human glioblastoma...

  6. A Mathematical Model for Simultaneous Saccharification and Co-fermentation (SSCF) of C6 and C5 Sugars

    DEFF Research Database (Denmark)

    Morales Rodriguez, Ricardo; Gernaey, Krist; Meyer, Anne S.

    2011-01-01

    saccharification and co-fermentation (SSCF) of C6 and C5 sugars. The model is constructed by combining existing mathematical models for enzymatic hydrolysis and co-fermentation. An inhibition of ethanol on cellulose conversion is introduced in order to increase the reliability. The mathematical model for the SSCF...

  7. Comparative study on the stem cell phenotypes of C6 cells under different culture conditions

    Institute of Scientific and Technical Information of China (English)

    ZHANG Suo-jun; YE Fei; XIE Rui-fan; HU Feng; WANG Bao-feng; WAN Feng; GUO Dong-sheng; LEI Ting

    2011-01-01

    Background Glioma stem cell (GSC) hypothesis posits that a subpopulation of cells within gliomas have true clonogenic and tumorigenic potential. Significantly, a more controversial correlate to GSC is that cells in different culture conditions might display distinct stem cell properties. Considering these possibilities, we applied an approach comparing stem cell characteristics of C6 glioma cells under different culture conditions.Methods C6 cells were cultured under three different growth conditions, i.e., adherent growth in conventional 10% serum medium, non-adherent spheres growth in serum-free medium, as well as adherent growth on laminin-coated flask in serum-free medium. Growth characteristics were detected contrastively through neurosphere formation assay and cell cycle analysis. Markers were determined by immunofluorescence, relative-quantitative reverse transcription (RT)-PCR,Western blotting and flow cytometry. Side population cells were analyzed via flow cytometry. Tumor models were detected by magnetic resonance imaging and hematoxylin & eosin staining. Data analyses were performed with SPSS software (17.0).Results C6 cells (C6-Adh, C6-SC-Sph and C6-SC-Adh) showed distinctive growth patterns and proliferation capacity.Compared to suspending C6-SC-Sph, adherent C6-Adh and C6-SC-Adh displayed higher growth ratio. C6-SC-Sph and C6-SC-Adh showed enhanced capability of neurosphere formation and self-renewal. High side population ratio was detected in C6-SC-Sph and C6-SC-Adh. CD133 was not detected in all three kinds of cells. Conversely, Nestin and β-Ⅲ-tubulin were demonstrated positive, nonetheless with no statistical significance (P >0.05). Interestingly, lower expression of glial fibrillary acidic protein was demonstrated in C6-SC-Sph and C6-SC-Adh. C6-Adh, C6-SC-Sph and C6-SC-Adh were all displayed in situ oncogenicity, while statistical difference of survival time was not confirmed.Conclusions C6 glioma cell line is endowed with some GSC

  8. Comparative study on the stem cell phenotypes of C6 cells under different culture conditions.

    Science.gov (United States)

    Zhang, Suo-Jun; Ye, Fei; Xie, Rui-Fan; Hu, Feng; Wang, Bao-Feng; Wan, Feng; Guo, Dong-Sheng; Lei, Ting

    2011-10-01

    Glioma stem cell (GSC) hypothesis posits that a subpopulation of cells within gliomas have true clonogenic and tumorigenic potential. Significantly, a more controversial correlate to GSC is that cells in different culture conditions might display distinct stem cell properties. Considering these possibilities, we applied an approach comparing stem cell characteristics of C6 glioma cells under different culture conditions. C6 cells were cultured under three different growth conditions, i.e., adherent growth in conventional 10% serum medium, non-adherent spheres growth in serum-free medium, as well as adherent growth on laminin-coated flask in serum-free medium. Growth characteristics were detected contrastively through neurosphere formation assay and cell cycle analysis. Markers were determined by immunofluorescence, relative-quantitative reverse transcription (RT)-PCR, Western blotting and flow cytometry. Side population cells were analyzed via flow cytometry. Tumor models were detected by magnetic resonance imaging and hematoxylin & eosin staining. Data analyses were performed with SPSS software (17.0). C6 cells (C6-Adh, C6-SC-Sph and C6-SC-Adh) showed distinctive growth patterns and proliferation capacity. Compared to suspending C6-SC-Sph, adherent C6-Adh and C6-SC-Adh displayed higher growth ratio. C6-SC-Sph and C6-SC-Adh showed enhanced capability of neurosphere formation and self-renewal. High side population ratio was detected in C6-SC-Sph and C6-SC-Adh. CD133 was not detected in all three kinds of cells. Conversely, Nestin and β-III-tubulin were demonstrated positive, nonetheless with no statistical significance (P > 0.05). Interestingly, lower expression of glial fibrillary acidic protein was demonstrated in C6-SC-Sph and C6-SC-Adh. C6-Adh, C6-SC-Sph and C6-SC-Adh were all displayed in situ oncogenicity, while statistical difference of survival time was not confirmed. C6 glioma cell line is endowed with some GSC phenotypes that can be moderately enriched in

  9. Immunotherapeutic targeting of shared melanoma-associated antigens in a murine glioma model.

    Science.gov (United States)

    Prins, Robert M; Odesa, Sylvia K; Liau, Linda M

    2003-12-01

    Immune-based treatments for central nervous system gliomas have traditionally lagged behind those of more immunogenic tumors such as melanoma. The relative paucity of defined glioma-associated antigens that can be targeted by the immune system may partially account for this situation. Antigens present on melanomas have been extensively characterized, both in humans and in murine preclinical models. Melanocytes and astrocytes are both derived embryologically from the neural ectoderm. Their neoplastic counterparts, malignant melanomas and gliomas, have been shown in humans to share common antigens at the RNA level. However, little is known concerning whether gliomas can be targeted by immune-based strategies that prime T cells to epitopes from melanoma-associated antigens (MAAs). In this study, we provide evidence that two common murine glioma cell lines (GL26 and GL261) express the melanoma antigens gp100 and tyrosinase-related protein 2 (TRP-2). To understand the immunogenicity of murine gliomas to CD8(+) T cells, we examined the ability of a MAA-specific CTL cell line to lyse the glioma cells, as well as the in vivo expansion of MAA-specific CD8(+) T cells in animals harboring gliomas. Both glioma cell lines were lysed by a human gp100-specific CTL cell line in vitro. Mice harboring s.c. GL26 gliomas possessed TRP-2-specific CD8(+) T cells, providing further evidence that these gliomas express the protein products in the context of MHC class I. Furthermore, MAA peptide-pulsed dendritic cells could prime T cells that specifically recognize GL26 glioma cells in vitro. Lastly, mice that were prevaccinated with human gp100 and TRP-2 peptide-pulsed dendritic cells had significantly extended survival when challenged with tumor cells in the brain, resulting in >50% long-term survival. These results suggest that shared MAAs on gliomas can be targeted immunotherapeutically, pointing the way to a new potential treatment option for patients with malignant gliomas.

  10. External irradiation models for intracranial 9L glioma studies

    Directory of Open Access Journals (Sweden)

    Feuvret Loïc

    2010-11-01

    Full Text Available Abstract Purpose Radiotherapy has been shown to be an effective for the treatment human glioma and consists of 30 fractions of 2 Gy each for 6-7 weeks in the tumor volume with margins. However. in preclinical studies, many different radiation schedules are used. The main purpose of this work was to review the relevant literature and to propose an external whole-brain irradiation (WBI protocol for a rat 9L glioma model. Materials and methods 9L cells were implanted in the striatum of twenty 344-Fisher rats to induce a brain tumor. On day 8, animals were randomized in two groups: an untreated group and an irradiated group with three fractions of 6 Gy at day 8, 11 and 14. Survival and toxicity were assessed. Results Irradiated rats had significantly a longer survival (p = 0.01. No deaths occurred due to the treatment. Toxicities of reduced weight and alopecia were increased during the radiation period but no serious morbidity or mortality was observed. Moreover, abnormalities disappeared the week following the end of the therapeutic schedule. Conclusions Delivering 18 Gy in 3 fractions of 6 Gy every 3 days, with mild anaesthesia, is safe, easy to reproduce and allows for standardisation in preclinical studies of different treatment regimens glioma rat model.

  11. Differential inhibitory effects of 2-azafluorenones on PI-PLC activation but not on PC-PLC- or PC-PLD-activation induced by histamine, PAF, PMA or A23187 in C6 glioma cells.

    Science.gov (United States)

    Wang, Hai-Long; Wang, Li-Chuan; Wei, Jiann-Wu

    2013-02-28

    In this study, C6 glioma cells were used to test the effects of 2-azafluorenone and its related compounds on membrane phosphatidylinositol (PI) and phosphatidylcholine (PC) turnover. An increase of [³H]-labeled inositol phosphate (IP1) formation by histamine (100 μM) or A23187 (100 nM) via the activation of phosphatidylinositol-specific phospholipase C (PI-PLC) to breakdown labeled substrate was observed, and this effect could be partially blocked by about half at 100 μM of 2-azafluorenones. Histamine induced the increase of IP1 formation, but failed to cause an increase in extracellularly releasing of [3H]choline metabolites, or intracellular accumulation of [³H]phosphscholine. However, platelet activation factor (PAF) from 0.2 to 1 μM, and phorbol 12-myristate-13-acetate (PMA) at 1 μM caused an increase in extracellularly releasing of [³H]choline metabolites, and intracellular accumulation of [³H]phosphocholine via the activation on phosphatidylcholine (PC)-PLC. These responses of PAF and PMA were not affected by 2-azafluorenone or 4-methyl-2-azafluorenone even at high concentration (10⁻⁴ M). A23187 induced an increase of intracellular [³H]choline release via the activation of PCphospholipase D (PLD). This increasing effect of 100 nM A23187 was not affected by 2-azafluorenone or 4-methyl-2-azafluorenone even at a high concentration of 10⁻⁴ M. In summary, the inhibitory effect of 2-azafluorenone and its related compound 4-methyl-2-azafluorenone was observed selectively on PIPLC, but not on PC-PLC or PC-PLD based on changes of products after the activation of these enzymes.

  12. Gene expression in bone mesenchymal stem cells transfered by tumor necrosis factor-related apoptosis-inducing ligand and these cells' effects on C6 glioma cells in vitro%肿瘤坏死因子相关凋亡诱导配体基因转染骨髓间充质干细胞后基因表达情况及其对C6胶质瘤细胞作用的体外研究

    Institute of Scientific and Technical Information of China (English)

    汤祥军; 张力; 王晓勋; 黄宽明; 鲁军体; 曹刚; 张相华; 涂汉军

    2013-01-01

    目的 探讨转染肿瘤坏死因子相关凋亡诱导配体(TRAIL)基因的骨髓间充质干细胞(BMSC)基因表达情况及其功能.方法 实验分三组,即转染TRAIL基因组、转染空载体组及空白对照组.用脂质体法将TRAIL转入绿色荧光蛋白(GFP)-BMSC中,反转录PCR法检测BMSC的TRAILmRNA水平,Western blot、免疫荧光法检测TRAIL蛋白的表达;将携带有TRAIL的GFP-BMSC同大鼠C6胶质瘤细胞共培养,通过四甲基偶氮唑蓝比色法检测其对肿瘤细胞的旁观者效应,Hochest-PI双染色法观察TRAIL转染的BMSC对C6细胞凋亡的影响.结果 免疫荧光检测显示,转染TRAIL 24、48 h的GFP-BMSC细胞质和细胞膜有TRAIL蛋白的表达,24h比48 h荧光强,空白对照组及空载体组细胞未见表达.反转录PCR、Western blot显示转染TRAIL基因组细胞TRAIL mRNA及蛋白高表达,空白对照组及空载体组未见表达.转染TRAIL的GFP-BMSC明显抑制C6细胞存活,抑制率为(62.7±0.1)%,高于空载体组的(16.7±0.1)%(P<0.05),同时转染TRAIL基因的BMSC可促进C6细胞的凋亡.结论 转染TRAIL的BMSC能够稳定表达目的基因,且能促进大鼠C6胶质瘤细胞凋亡,具有明显的旁观者效应.%Objective To investigate the gene expression in bone mesenchymal stem cells transferred by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its effect on C6 glioma cells in vitro.Methods The experiment was divided into three groups,the test group transfected with TRAIL gene to BMSC,control group of BMSC transfected with empty liposomal vector,and blank control of BMSC alone.After transfering the TRAIL into GFP-BMSC with Liposomes,the expression of TRAIL was detected by RTPCR,Western blot,and immunofluorescence.After co-culturing C6 glioma cells with GFP-BMSC-TRAIL,the bystander effect of TRAIL was detected by MTT assay,and C6 cells apoptosis was detected by immunohistochemical method.Results GFP-BMSC-TRAIL vector was successfully constructed

  13. Pre-Clinical Models of Diffuse Intrinsic Pontine Glioma

    Directory of Open Access Journals (Sweden)

    Oren J Becher

    2015-07-01

    Full Text Available Diffuse Intrinsic Pontine Glioma (DIPG is a rare and incurable brain tumor that arises in the brainstem of children predominantly between the ages of six and eight. Its intricate morphology and involvement of normal pons tissue precludes surgical resection, and the standard of care today remains fractionated radiation alone. In the past 30 years, there have been no significant advances made in the treatment of DIPG. This is largely because we lack good models of DIPG and therefore have little biological basis for treatment. In recent years however, due to increased biopsy and acquisition of autopsy specimens, research is beginning to unravel the genetic and epigenetic drivers of DIPG. Insight gleaned from these studies has led to improvements in approaches to both model these tumors in the lab, as well as to potentially treat them in the clinic. This review will detail the initial strides towards modeling DIPG in animals, which included allograft and xenograft rodent models using non-DIPG glioma cells. Important advances in the field came with the development of in vitro cell and in vivo xenograft models derived directly from autopsy material of DIPG patients or from human embryonic stem cells. Lastly, we will summarize the progress made in the development of genetically engineered mouse models of DIPG. Cooperation of studies incorporating all of these modeling systems to both investigate the unique mechanisms of gliomagenesis in the brainstem and to test potential novel therapeutic agents in a preclinical setting will result in improvement in treatments for DIPG patients.

  14. Optic glioma

    Science.gov (United States)

    Glioma - optic; Optic nerve glioma; Juvenile pilocytic astrocytoma; Brain cancer - optic glioma ... Optic gliomas are rare. The cause of optic gliomas is unknown. Most optic gliomas are slow-growing ...

  15. Delta-24-RGD oncolytic adenovirus elicits anti-glioma immunity in an immunocompetent mouse model

    NARCIS (Netherlands)

    H. Jiang (Hao); K. Clise-Dwyer (Karen); K.E. Ruisaard (Kathryn); X. Fan (Xuejun); W. Tian (Weihua); J. Gumin (Joy); M.L.M. Lamfers (Martine); A. Kleijn (Anne); F.F. Lang (Frederick); S. Yung (Sun); L.M. Vence (Luis); C. Gomez-Manzano (Candelaria); J. Fueyo (Juan)

    2014-01-01

    textabstractBackground: Emerging evidence suggests anti-cancer immunity is involved in the therapeutic effect induced by oncolytic viruses. Here we investigate the effect of Delta-24-RGD oncolytic adenovirus on innate and adaptive anti-glioma immunity. Design: Mouse GL261-glioma model was set up in

  16. Development of a mathematical model describing hydrolysis and co-fermentation of C6 and C5 sugars

    DEFF Research Database (Denmark)

    Morales Rodriguez, Ricardo; Gernaey, Krist; Meyer, Anne S.

    2010-01-01

    the degree of reliability. The mathematical model for the SSCF has been tested for a modified version of the process flowsheet proposed by the National Renewable Energy Laboratory (NREL). The model can now be used to evaluate different process configurations for 2G bioethanol production using corn stover......Reliable production of biofuels and specifically bioethanol has attracted a significant amount of research recently. Within this context, this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous...... saccharification and co-fermentation (SSCF) of C6 and C5 sugars. Model construction has been carried out by combining existing mathematical models for enzymatic hydrolysis on the one hand and co-fermentation on the other hand. An inhibition of ethanol on cellulose conversion was introduced in order to increase...

  17. Simulating Radiotherapy Effect in High-Grade Glioma by Using Diffusive Modeling and Brain Atlases

    Directory of Open Access Journals (Sweden)

    Alexandros Roniotis

    2012-01-01

    Full Text Available Applying diffusive models for simulating the spatiotemporal change of concentration of tumour cells is a modern application of predictive oncology. Diffusive models are used for modelling glioblastoma, the most aggressive type of glioma. This paper presents the results of applying a linear quadratic model for simulating the effects of radiotherapy on an advanced diffusive glioma model. This diffusive model takes into consideration the heterogeneous velocity of glioma in gray and white matter and the anisotropic migration of tumor cells, which is facilitated along white fibers. This work uses normal brain atlases for extracting the proportions of white and gray matter and the diffusion tensors used for anisotropy. The paper also presents the results of applying this glioma model on real clinical datasets.

  18. Transferrin modified PEG-PLA-resveratrol conjugates: in vitro and in vivo studies for glioma.

    Science.gov (United States)

    Guo, Wanhua; Li, Aimei; Jia, Zhijun; Yuan, Yi; Dai, Haifeng; Li, Hongxiu

    2013-10-15

    Glioblastoma is one of the most malignant brain tumors with a poor prognosis. In this study, we examined the effects of transferrin (Tf)-modified poly ethyleneglycol-poly lactic acid (PEG-PLA) nanoparticles conjugated with resveratrol (Tf-PEG-PLA-RSV) to glioma therapy in vitro and in vivo. The cell viability of Tf-PEG-PLA-RSV on C6 and U87 glioma cells was determined by the MTT assay. In vivo biodistribution and antitumor activity were investigated in Brain glioma bearing rat model of C6 glioma by i.p. administration of RSV-polymer conjugates. We found that the average diameter of each Tf-PEG-PLA-RSV is around 150 nm with 32 molecules of Tf on surface. In vitro cytotoxicity of PEG-PLA-RSV against C6 and U87 cells was higher than that of free RSV, and further the modification of Tf enhanced the cytotoxicity of the RSV-polymer conjugates as a result of the increased cellular uptake of the RSV-modified conjugates by glioma cells. In comparison with free RSV, RSV conjugates could significantly decrease tumor volume and accumulate in brain tumor, which resulted in prolonging the survival of C6 glioma-bearing rats. These results suggest that Tf-NP-RSV had a potential of therapeutic effect to glioma both in vitro and in vivo and might be a potential candidate for targeted therapy of glioma and worthy of further investigation.

  19. Modeling Glioma Growth and Invasion in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Hanna Teresa Witte

    2009-09-01

    Full Text Available Glioblastoma is the most common and most malignant intrinsic human brain tumor, characterized by extensive invasion and proliferation of glial (astrocytic tumor cells, frequent activation of tyrosine kinase receptor signaling pathways, relative resistance to chemotherapy and radiotherapy, and poor prognosis. Using the Gal4-UAS system, we have produced glioma models in Drosophila by overexpressing homologs of human tyrosine kinase receptors under control of the glia-specific promoter reversed polarity (repo. Glial overexpression of activated epidermal growth factor receptor (EGFR resulted in enhanced proliferation and migration of larval glial cells with increased numbers in the eye imaginal disc, diffuse tumor-like enlargement of the optic stalk, and marked ectopic invasion of glial cells along the optic nerve. Glial overexpression of the downstream kinase PI3K showed similar pathology. Overexpression of activated pvr (platelet-derived growth factor receptor/vascular endothelial growth factor receptor homolog led to migration of glial cells along the optic nerve, whereas expression of activated htl (fibroblast growth factor receptor 1 homolog and INR (insulin receptor showed markedly elevated numbers of glial cells in the optic stalk. The EGFR/phosphatidylinositol 3-phosphate kinase (PI3K phenotype was partly reverted by the administration of the EGFR tyrosine kinase inhibitor gefitinib and completely rescued by the PI3K inhibitor wortmannin and the Akt inhibitor triciribine. We suggest that Drosophila models will be useful for deciphering signaling cascades underlying abnormal behavior of glioma cells for genetic screens to reveal interacting genes involved in gliomagenesis and for experimental therapy approaches.

  20. The 9LLUC/Wistar rat glioma model is not suitable for immunotherapy

    Institute of Scientific and Technical Information of China (English)

    Liping Yang; Jingxiang Zhao; Guihong Zhou; Yunfang Wang; Lusi Li; Hongfeng Yuan; Xue Nan; Lidong Guan; Xuetao Pei

    2012-01-01

    The availability of a well-characterized animal brain tumor model will play an important role in identifying treatments for human brain tumors. Wistar rats bearing 9L glioma cells can develop solid, well-circumcised tumors, and may be a useful animal model for the evaluation of various therapeutic approaches for gliosarcomas. In this study, the 9L/Wistar rat glioma model was produced by intracerebral implantation of 9LLUC glioma cells syngenic to Fischer 344 (F344) rats. Bioluminescence imaging showed that tumors progressively grew from day 7 to day 21 in 9LLUC/F344 rats, and tumor regression was found in some 9LLUC/Wistar rats. Hematoxylin-eosin staining verified that intracranial tumors were gliomas. Immunohistochemistry results demonstrated that no CD4- and CD8-positive cells were found in the syngeneic 9LLUC/F344 model. However, many infiltrating CD4- and CD8-positive cells were observed within the tumors of the 9LLUC/Wistar model. Our data suggests that compared with 9L/F344 rats, 9L glioma Wistar rats may not be suitable for evaluating brain glioma immunotherapies, even though the model induced an immune response and exhibited tumor regression.

  1. The functional curcumin liposomes induce apoptosis in C6 glioblastoma cells and C6 glioblastoma stem cells in vitro and in animals

    Science.gov (United States)

    Wang, Yahua; Ying, Xue; Xu, Haolun; Yan, Helu; Li, Xia; Tang, Hui

    2017-01-01

    Glioblastoma is a kind of malignant gliomas that is almost impossible to cure due to the poor drug transportation across the blood–brain barrier and the existence of glioma stem cells. We prepared a new kind of targeted liposomes in order to improve the drug delivery system onto the glioma cells and induce the apoptosis of glioma stem cells afterward. In this experiment, curcumin was chosen to kill gliomas, while quinacrine was used to induce apoptosis of the glioma stem cells. Also, p-aminophenyl-α-D-mannopyranoside could facilitate the transport of liposomes across the blood–brain barrier and finally target the brain glioma cells. The cell experiments in vitro indicated that the targeted liposomes could significantly improve the anti-tumor effects of the drugs, while enhancing the uptake effects, apoptosis effects, and endocytic effects of C6 glioma cells and C6 glioma stem cells. Given the animal experiments in vivo, we discovered that the targeted liposomes could obviously increase the survival period of brain glioma-bearing mice and inhibit the growth of gliomas. In summary, curcumin and quinacrine liposomes modified with p-aminophenyl-α-D-mannopyranoside is a potential preparation to treat brain glioma cells and brain glioma stem cells. PMID:28260885

  2. 铀氢锆堆中子源辐照含硼C6胶质瘤细胞的生物学效应研究%Biological effects of boron-absorbed C6 glioma cells irradiated by UHZr reactor neutron source

    Institute of Scientific and Technical Information of China (English)

    江新标; 赵英; 曹锐锋; 肖艳; 陈伟; 屠荆; 章翔

    2005-01-01

    利用蒙卡程序MCNP/4B(Monte Carlo N-particle transportcode/4B)设计了C6细胞辐照实验的铀氢锆堆中子源.建立了细胞培养、孵育、L-BPA(L-boron phenylalanine)给药、细胞内宏观硼浓度测定及辐照实验方法,观察了BNCT(Boron neutron capture therapy)辐照实验对体外C6胶质瘤细胞的放射生物学效应,研究了C6细胞BNCT辐照效应与照射剂量之间的关系.试验结果表明,在同等吸收剂量下,BNCT对C6细胞的杀伤作用远远大于γ射线.

  3. The role of myosin II in glioma invasion: A mathematical model

    Science.gov (United States)

    Lee, Wanho; Lim, Sookkyung; Kim, Yangjin

    2017-01-01

    Gliomas are malignant tumors that are commonly observed in primary brain cancer. Glioma cells migrate through a dense network of normal cells in microenvironment and spread long distances within brain. In this paper we present a two-dimensional multiscale model in which a glioma cell is surrounded by normal cells and its migration is controlled by cell-mechanical components in the microenvironment via the regulation of myosin II in response to chemoattractants. Our simulation results show that the myosin II plays a key role in the deformation of the cell nucleus as the glioma cell passes through the narrow intercellular space smaller than its nuclear diameter. We also demonstrate that the coordination of biochemical and mechanical components within the cell enables a glioma cell to take the mode of amoeboid migration. This study sheds lights on the understanding of glioma infiltration through the narrow intercellular spaces and may provide a potential approach for the development of anti-invasion strategies via the injection of chemoattractants for localization. PMID:28166231

  4. Endothelial PKCα-MAPK/ERK-phospholipase A2 pathway activation as a response of glioma in a triple culture model. A new role for pericytes?

    Science.gov (United States)

    Anfuso, Carmelina Daniela; Motta, Carla; Giurdanella, Giovanni; Arena, Valeria; Alberghina, Mario; Lupo, Gabriella

    2014-04-01

    In view of understanding the molecular mechanisms through which angiogenic switch on happens in the early phases of reciprocal interaction between tumor and cells constituting microvessel, a triple culture model in which endothelial cells (EC), pericytes (PC) and glioma C6 cells were cultured together. In the present work, we observed that C6 enhanced EC proliferation. This effect was reduced by cytosolic and Ca(2+)-independent phospholipase A2 (cPLA2 and iPLA2), cyclooxygenase-2 (COX-2), PI3-K, MEK-1, and ERK1/2 inhibitors and by siRNAs against both PLA2s. In EC, C6 induced an increase in iPLA2, cPLA2 and COX-2 total protein expression. Moreover, the increase in endothelial cPLA2 phosphorylation was attenuated by kinase inhibitors. Both EC proliferation and signal protein phosphorylation were attenuated when PC were in triple culture. In EC/C6 supernatants, and, in a lesser extent, in EC/PC co-cultures, an enhancement in prostaglandins E2 (PGE2) was found. The presence of PC in triple-cultures caused a decrease in production of PGE2 respect to EC/C6 double-cultures. In all systems, AACOCF3 and BEL significantly reduced PGE2 secretion. In Matrigel-based assays, emerging branch points from EC cell bodies and tubule-like structures were observed. C6 conditioned EC/PC co-cultures in constituting poorly organized tubules. Transfection of EC with c- and iPLA2 siRNA strongly reduced in vitro tubulogenesis. Data here reported indicate that PKCα, ERK kinase phosphorylation, PLA2s and COX-2 activation, and PGE2 production in EC stimulated by tumor cells are coincident phenomena and could represent therapeutic targets in chemoprevention of glioma. Moreover, PC exhibited an important "modulating" role in the initial stages of angiogenesis driven by a brain tumor.

  5. 吗啡对C6胶质瘤细胞嘌吟核苷酸代谢相关酶基因表达的影响%Effect of morphine on expression of gene of enzymes related to purine nucleotide metabolism in c6 glioma

    Institute of Scientific and Technical Information of China (English)

    刘剑凯; 洪敏; 赵小冬

    2003-01-01

    目的研究吗啡对C6胶质瘤细胞嘌呤核苷酸合成代谢与分解代谢的影响.方法吗啡(10 μg/ml培养基)作用于C6胶质瘤细胞6 h、12 h、24 h、48 h、72 h;纳络酮(1 μmol/L)作用于C6胶质瘤细胞1 h后,加吗啡(10 μg/ml)作用24 h.提取细胞总RNA,采用反转录-聚合酶链反应(RT-PCR)方法检测次黄嘌呤-鸟嘌呤磷酸核糖转移酶(HGPRT)及腺苷激酶(AK)的基因转录产物;采用反转录-聚合酶链反应及Southern(RT-PCR-Southern)杂交方法检测黄嘌呤脱氧酶(XD)/黄嘌呤氧化酶(XO)基因转录产物.结果 C6胶质瘤细胞暴露于吗啡6 h, 12 h, 24 h,48 h,HGPRT 基因表达均明显降低;而C6胶质瘤细胞AK基因表达在暴露于吗啡24 h 明显降低;HGPRT 与AK基因表达又分别于吗啡作用胶质瘤细胞72 h和48 h回升;纳络酮不能阻断吗啡对HGPRT与AK基因表达降低的作用.吗啡作用于C6胶质瘤细胞与相应时段对照组相比,XD/XO基因转录产物均明显增多;纳络酮能够阻断吗啡对XD/XO基因表达增强的作用.结论吗啡通过其他非μ受体途径介导对C6胶质瘤细胞嘌呤核苷酸补救合成关键酶HGPRT与AK基因表达降低的作用;吗啡通过μ受体途径介导对C6胶质瘤细胞嘌呤核苷酸分解代谢关键酶XD/XO基因表达增强的作用.

  6. Effect of ginsenoside Rg1 on the apoptosis of C6 glioma cells induced by oxygen and glucose deprivation%人参皂苷Rg1对缺糖缺氧所致C6胶质细胞凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    胡金凤; 宁娜; 薛薇; 苑玉和; 张均田; 陈乃宏

    2009-01-01

    目的:观察人参皂苷Rg1(Rg1)对缺糖缺氧所致C6胶质细胞损伤的保护作用及其机制.方法:采用MTT法检测了Rg1对缺糖缺氧所致胶质细胞C6的存活;采用流式细胞术检测了Rg1对胶质C6细胞凋亡的影响;采用Western blot方法检测了Rg1对凋亡相关蛋白p38 MAPK磷酸化激活、P53、Caspase 3表达的影响,以及BDNF表达的影响.结果:Rg1通过抑制了缺糖缺氧所致C6细胞的凋亡而增加细胞的存活率,且抑制了p38 MAPK的磷酸化激活,抑制凋亡促进蛋白P53、Caspase 3的表达,并促进BDNF的表达.结论:Rg1可能通过抑制胶质细胞损伤而促进脑缺血中神经元的修复.

  7. Effect of NPPB and niflumic acid on expression of GCL and CLICA in H2O2 injured C6 glioma cells%NPPB和尼弗灭酸对H2O2损伤C6胶质细胞谷氨酸半胱氨酸合成酶及CLIC4表达的影响

    Institute of Scientific and Technical Information of China (English)

    孔晓霞; 张宏宇; 李扬; 李洪岩; 康劲松; 孙连坤

    2008-01-01

    目的:观察氯通道阻断剂5-硝基-2-(3-苯丙胺)-苯甲酸(NPPB)、尼弗灭酸(NFA)对H2O2诱导的神经胶质瘤C6细胞损伤的影响.方法:MTT法检测NPPB、NFA、H2O2作用的c6细胞生存率;紫外分光光度法检测乳酸脱氢酶(LDH)释放率以及谷胱甘肽GSH水平;RT-PCR检测谷氨酸半胱氨酸合成酶(GCL)亚单位GCLC、GCLM及线粒体氯通道(CLICA)mRNA表达;Western blotting检测CLICA的蛋白水平.结果:与对照组相比,H2O2组c6细胞存活率和GSH含量明显降低;LDH释放率增加;GCLC、GCLM、CLICA mRNA表达降低;CLICA蛋白水平明显增强.NPPB或NFA与H2O2联合作用于C6细胞组,与单独应用H2O2组相比,细胞存活率和GSH含量未见明显变化;LDH释放率降低;GCLC、CCLM mRNA 表达未见明显差异;CLIC4蛋白表达下降.结论:氯通道阻断剂NPPB或NFA能够在一定程度上减轻氧化应激引起的C6细胞损伤,可能与调节细胞膜功能和下调CUC4蛋白表达有关.

  8. GDNF剪接体α-pro-GDNF在大鼠C6胶质瘤细胞中的表达及其意义%The expression and significaceof GDNF splice variant α-pro-GDNF in rat C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    魏赫; 李亨; 雷宇; 于如同; 虞正权; 高殿帅

    2016-01-01

    目的:探讨大鼠C6胶质瘤细胞中GDNF选择性剪接体的表达情况及意义.方法:通过检测C6胶质瘤细胞中GDNF基因△78位点剪接体α-pro-GDNF mRNA和β-pro-GDNF mRNA及其受体蛋白GFRα1、GFRα2、Ret和NCAM表达,结合介导肿瘤迁移相关蛋白RhoA、Cdc42、Rac1的表达情况,分析其相关关系.结果:(1)C6胶质瘤细胞中,可以检测到α-pro-GDNF和β-pro-GDNF的mRNA表达,且α-pro-GDNF mRNA表达水平比β-pro-GDNF高;与星形胶质细胞相比,α-pro-GDNF mRNA表达水平的增高趋势较β-pro-GDNF明显;(2)C6胶质瘤细胞中RhoA mRNA表达水平与α-pro-GDNF mRNA表达水平成显著正相关(R2=0.699,P<0.05),Cdc 42 mRNA表达水平与α-pro-GDNF mRNA表达水平呈显著正相关(R2=0.803,P<0.05),与β-pro-GDNF mRNA表达相关性不显著.结论:C6胶质瘤中α-pro-GDNF具有优先表达,可能与胶质瘤细胞的迁移具有相关性.

  9. Utilization of {sup 13}C-enriched substrates for the NMR study of the channelling of Krebs cycle intermediates in glioma C6; Utilisation de substrats enrichis en {sup 13}C pour l`etude par RMN de la canalisation des intermediaires du cycle de Krebs dans le gliome C6

    Energy Technology Data Exchange (ETDEWEB)

    Merle, M.; Peron, M.; Valeins, H.; Canioni, P. [Bordeaux-2 Univ., 33 (France)

    1994-12-31

    Unequal enrichments are observed for the C2 and C3 carbons of glutamate (C2>C3) and of aspartate (C3>C2) during incubation of C6 cells with (1-{sup 13} C) glucose. In order to study if this result is the result of an entry of {sup 13}C at the oxalo-acetate level or of another phenomenon, the enrichment distribution on asparte C1 and C4 carbons of C6 cells incubated with (1-{sup 13} C) glucose and the enrichment of C2 and C3 carbons of glutamate during cell incubation with (2-{sup 13} C) acetate, i.e. cases where the entry of {sup 13}C in the cycle, via the activity of the pyruvate carboxylase, is very unlikely, are examined. 4 figs., 1 tab., 1 ref.

  10. A drosophila model for EGFR-Ras and PI3K-dependent human glioma.

    Directory of Open Access Journals (Sweden)

    Renee D Read

    2009-02-01

    Full Text Available Gliomas, the most common malignant tumors of the nervous system, frequently harbor mutations that activate the epidermal growth factor receptor (EGFR and phosphatidylinositol-3 kinase (PI3K signaling pathways. To investigate the genetic basis of this disease, we developed a glioma model in Drosophila. We found that constitutive coactivation of EGFR-Ras and PI3K pathways in Drosophila glia and glial precursors gives rise to neoplastic, invasive glial cells that create transplantable tumor-like growths, mimicking human glioma. Our model represents a robust organotypic and cell-type-specific Drosophila cancer model in which malignant cells are created by mutations in signature genes and pathways thought to be driving forces in a homologous human cancer. Genetic analyses demonstrated that EGFR and PI3K initiate malignant neoplastic transformation via a combinatorial genetic network composed primarily of other pathways commonly mutated or activated in human glioma, including the Tor, Myc, G1 Cyclins-Cdks, and Rb-E2F pathways. This network acts synergistically to coordinately stimulate cell cycle entry and progression, protein translation, and inappropriate cellular growth and migration. In particular, we found that the fly orthologs of CyclinE, Cdc25, and Myc are key rate-limiting genes required for glial neoplasia. Moreover, orthologs of Sin1, Rictor, and Cdk4 are genes required only for abnormal neoplastic glial proliferation but not for glial development. These and other genes within this network may represent important therapeutic targets in human glioma.

  11. The role of extracellular matrix in glioma invasion: a cellular Potts model approach.

    Science.gov (United States)

    Rubenstein, Brenda M; Kaufman, Laura J

    2008-12-15

    In this work, a cellular Potts model based on the differential adhesion hypothesis is employed to analyze the relative importance of select cell-cell and cell-extracellular matrix (ECM) contacts in glioma invasion. To perform these simulations, three types of cells and two ECM components are included. The inclusion of explicit ECM with an inhomogeneous fibrous component and a homogeneously dispersed afibrous component allows exploration of the importance of relative energies of cell-cell and cell-ECM contacts in a variety of environments relevant to in vitro and in vivo experimental investigations of glioma invasion. Simulations performed here focus chiefly on reproducing findings of in vitro experiments on glioma spheroids embedded in collagen I gels. For a given range and set ordering of energies associated with key cell-cell and cell-ECM interactions, our model qualitatively reproduces the dispersed glioma invasion patterns found for most glioma cell lines embedded as spheroids in collagen I gels of moderate concentration. In our model, we find that invasion is maximized at intermediate collagen concentrations, as occurs experimentally. This effect is seen more strongly in model gels composed of short collagen fibers than in those composed of long fibers, which retain significant connectivity even at low density. Additional simulations in aligned model matrices further elucidate how matrix structure dictates invasive patterns. Finally, simulations that allow invading cells to both dissolve and deposit ECM components demonstrate how Q-Potts models may be elaborated to allow active cell alteration of their surroundings. The model employed here provides a quantitative framework with which to bound the relative values of cell-cell and cell-ECM interactions and investigate how varying the magnitude and type of these interactions, as well as ECM structure, could potentially curtail glioma invasion.

  12. Performance analysis of successive over relaxation method for solving glioma growth model

    Science.gov (United States)

    Hussain, Abida; Faye, Ibrahima; Muthuvalu, Mohana Sundaram

    2016-11-01

    Brain tumor is one of the prevalent cancers in the world that lead to death. In light of the present information of the properties of gliomas, mathematical models have been developed by scientists to quantify the proliferation and invasion dynamics of glioma. In this study, one-dimensional glioma growth model is considered, and finite difference method is used to discretize the problem. Then, two stationary methods, namely Gauss-Seidel (GS) and Successive Over Relaxation (SOR) are used to solve the governing algebraic system. The performance of the methods are evaluated in terms of number of iteration and computational time. On the basis of performance analysis, SOR method is shown to be more superior compared to GS method.

  13. 吗啡对C6神经胶质瘤细胞Glu和Gln含量及其代谢关键酶转录活性的影响%Effects of morphine on contents of glutamate and glutamine in cultured supernatant and transcripts of related metabolic key enzymes in C6 glioma cells

    Institute of Scientific and Technical Information of China (English)

    王少华; 孙吉凤; 刘剑凯; 张连芝; 邓志会

    2008-01-01

    目的:研究吗啡对C6神经胶质瘤细胞谷氨酸(Glu)-谷氨酰胺(Gln)循环代谢产物含量及其相关酶基因转录的影响,探讨吗啡依赖与耐受的作用机制.方法:传代培养的C6神经胶质瘤细胞,随机分为4组:对照组(C组),吗啡组(M组),纳洛酮加吗啡组(N+M组)和纳洛酮组(N组),应用比色法测定C6神经胶质瘤细胞培养上清液中Glu及Gln的含量,应用半定量RT-PCR法测定C6神经胶质瘤细胞Glu-Gln循环关键酶谷氨酰胺合成酶(GS)及谷氨酸脱氢酶(GDH)mRNA相对含量的变化.结果:与C组比较,M组细胞外Glu含量显著性增加(P0.05).与C组比较,M组、N组细胞GS mRNA转录活性均显著降低(P<0.01).与M组比较,N+M组细胞GS mRNA转录活性显著升高(P<0.01);与C组比较,M组细胞GDH mRNA转录活性升高(P<0.05).与M组比较,N+M组细胞GDHmRNA转录活性显著性升高(P<0.01).结论:吗啡可能通过对Glu-Gln循环关键酶GS和GDH基因转录活性的影响调节细胞外Gln和Glu浓度,其机制可能与吗啡依赖等作用相关.

  14. Bevacizumab Targeting Diffuse Intrinsic Pontine Glioma: Results of 89Zr-Bevacizumab PET Imaging in Brain Tumor Models

    NARCIS (Netherlands)

    Jansen, M.H.; Lagerweij, T.; Sewing, A.C.; Vugts, D.J.; Vuurden, D.G. van; Molthoff, C.F.; Caretti, V.; Veringa, S.J.; Petersen, N.; Carcaboso, A.M.; Noske, D.P.; Vandertop, W.P.; Wesseling, P.; Dongen, G.A. van; Kaspers, G.J.; Hulleman, E.

    2016-01-01

    The role of the VEGF inhibitor bevacizumab in the treatment of diffuse intrinsic pontine glioma (DIPG) is unclear. We aim to study the biodistribution and uptake of zirconium-89 ((89)Zr)-labeled bevacizumab in DIPG mouse models. Human E98-FM, U251-FM glioma cells, and HSJD-DIPG-007-FLUC primary DIPG

  15. 脂膜微囊承载紫杉醇靶向性治疗C6胶质瘤的体内外实验研究%The targeted therapeutic effect of a lipid-coated microbubble carrying Taxol on C6 glioma in vivo and vitro

    Institute of Scientific and Technical Information of China (English)

    宫崧峰; 李新钢; 李刚; 王东海; 徐淑军; 周旭东

    2007-01-01

    目的:在体内外研究脂膜微囊(LCM)承载紫杉醇(Taxol)治疗大鼠颅内C6质瘤的机制.方法:体外实验应用紫杉醇-脂膜微囊(Taxol-LCM)或单用LCM处理C6细胞系,采用免疫荧光显微镜或激光共聚焦显微镜下观察LCM在肿瘤细胞内的分布特点,用药前后肿瘤细胞形态的改变和细胞内超微结构的变化,动态观察LCM进入细胞的全过程;体内实验建立大鼠C6胶质瘤动物模型12只,成瘤大鼠分为4组:注射LCM-Taxol组、注射LCM组、注射Taxol组及载瘤动物组,每组取一只在最后一次尾静脉注射相应药物后处死,获取大鼠脑组织标本,进行油红O染色,观察LCM在肿瘤位点分布的特点;同时观察不同处理组大鼠的生存期.结果:体外实验表明,Taxol可结合于LCM并被胶质瘤细胞内吞,起到很强的的杀伤肿瘤细胞作用.其内吞过程为LCM先结合于细胞膜表面,后在细胞内重新分布,最终被细胞浆内的酸性成分所降解.体内油红O染色显示,注射LCM-Taxol组肿瘤区域有LCM聚集,胶质瘤明显坏死;而注射LCM组,肿瘤区域有LCM出现,但肿瘤区域无明显坏死;注射Taxol组及载瘤动物组肿瘤区域无明显坏死;生存期结果示,Taxol-LCM组生存期明显长于其他3组,而与其他3组生存期比较差异不明显.结论:LCM可承载Taxol在体内外起到杀伤胶质瘤细胞的作用.

  16. Theraputic Effect of Lipid-Coated Microbubble Carrying Taxol on Rat with Intracranial C6 Glioma%脂膜微囊承载紫杉醇靶向性治疗大鼠颅内C6胶质瘤的实验研究

    Institute of Scientific and Technical Information of China (English)

    宫崧峰; 李新钢

    2009-01-01

    目的:研究脂膜微囊承载紫杉醇靶向性治疗大鼠颅内C6胶质瘤的机制.方法:建立大鼠C6胶质瘤动物模型12只,成瘤大鼠分为四组;注射LCM-Taxol组,注射LCM组.注射Taxol组及载瘤动物组,每组取一只在最后一次尾静脉注射相应药物后处死,获取大鼠脑组织标本,进行常规HE染色,油红O染色.观察LCM在肿瘤位点分布的特点;同时观察不同处理组大鼠的生存期.结果:油红O染色显示注射LCM-Taxol组,肿瘤区域有LCM聚集,胶质瘤明显坏死;而注射LCM组,肿瘤区域有LCM出现,但肿瘤区域无明显坏死;注射TAXOL组及载瘤动物组肿瘤区域无明显坏死;生存期结果示Taxol-LCM组生存期明显长于注射LCM组和注射Taxol组及载瘤动物组,而注射LCM组、注射Taxol组、单纯载瘤动物组生存期差异不明显.结论:LCM-Taxol可以承载药物靶向性聚集于颅内胶质瘤区域,并起到杀伤肿瘤的作用,明显延长了大鼠的生存期;而注射LCM组、注射Taxol组未能明显延长载瘤大鼠的生存期.

  17. A computational model incorporating neural stem cell dynamics reproduces glioma incidence across the lifespan in the human population.

    Directory of Open Access Journals (Sweden)

    Roman Bauer

    Full Text Available Glioma is the most common form of primary brain tumor. Demographically, the risk of occurrence increases until old age. Here we present a novel computational model to reproduce the probability of glioma incidence across the lifespan. Previous mathematical models explaining glioma incidence are framed in a rather abstract way, and do not directly relate to empirical findings. To decrease this gap between theory and experimental observations, we incorporate recent data on cellular and molecular factors underlying gliomagenesis. Since evidence implicates the adult neural stem cell as the likely cell-of-origin of glioma, we have incorporated empirically-determined estimates of neural stem cell number, cell division rate, mutation rate and oncogenic potential into our model. We demonstrate that our model yields results which match actual demographic data in the human population. In particular, this model accounts for the observed peak incidence of glioma at approximately 80 years of age, without the need to assert differential susceptibility throughout the population. Overall, our model supports the hypothesis that glioma is caused by randomly-occurring oncogenic mutations within the neural stem cell population. Based on this model, we assess the influence of the (experimentally indicated decrease in the number of neural stem cells and increase of cell division rate during aging. Our model provides multiple testable predictions, and suggests that different temporal sequences of oncogenic mutations can lead to tumorigenesis. Finally, we conclude that four or five oncogenic mutations are sufficient for the formation of glioma.

  18. Glioma-derived mutations in isocitrate dehydrogenase 2 beneficial to traditional chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yuejun, E-mail: yjfu@sxu.edu.cn [Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006 (China); Huang, Rui; Zheng, Yali; Zhang, Zhiyun; Liang, Aihua [Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006 (China)

    2011-07-01

    Highlights: {yields} IDH1 and IDH2 mutations are not detected in the rat C6 glioma cell line model. {yields} IDH2 mutations are not required for the tumorigenesis of glioma. {yields} IDH2{sup R172G} can sensitize glioma sensitivity to chemotherapy through NADPH levels. {yields} IDH2{sup R172G} can give a benefit to traditional chemotherapy of glioma. {yields} This finding serves as an important complement to existing research on this topic. -- Abstract: Heterozygous mutations in either the R132 residue of isocitrate dehydrogenase I (IDH1) or the R172 residue of IDH2 in human gliomas were recently highlighted. In the present study, we report that mutations of IDH1 and IDH2 are not detected in the rat C6 glioma cell line model, which suggests that these mutations are not required for the development of glioblastoma induced by N,N'-nitroso-methylurea. The effects of IDH2 and IDH2{sup R172G} on C6 cells proliferation and sensitivity to chemotherapy and the possible mechanism are analyzed at the cellular level. IDH1 and IDH2 mutations lead to simultaneous loss and gain of activities in the production of {alpha}-ketoglutarate ({alpha}-KG) and 2-hydroxyglutarate (2HG), respectively, and result in lowering NADPH levels even further. The low NADPH levels can sensitize tumors to chemotherapy, and account for the prolonged survival of patients harboring the mutations. Our data extrapolate potential importance of the in vitro rat C6 glioma cell model, show that the IDH2{sup R172G} mutation in gliomas may give a benefit to traditional chemotherapy of this cancer and serve as an important complement to existing research on this topic.

  19. Determination of Teniposide in C6 Glioma Tumor-Bearing Rat Brain Tissue by Sensitive Liquid Chromatography/Tandem Mass Spectrometry%HPLC-MS/MS法测定C6胶质瘤荷瘤大鼠脑组织中替尼泊苷的浓度

    Institute of Scientific and Technical Information of China (English)

    樊宏伟; 于翠霞; 孙敏; 蔡超俊; 李英斌

    2009-01-01

    目的 建立测定C6胶质瘤荷瘤大鼠脑组织中替尼泊苷含量的高效液相色谱-串联质谱联用法.方法 脑组织匀浆后用乙酸乙酯-二氯甲烷(4:1)液-液提取,流动相重组离心后进样分析.色谱柱为Lichrospher C18(2.1 mm×100 mm,5 μm)柱,依托泊苷为内标,以甲醇-0.1%甲酸的5mmol·L-1乙酸铵(70:30)为流动相,流速0.2mL·min-1,柱温35℃,以多反应离子监测方式检测:替尼泊苷[M+NH4]+,m/z 674/383;内标:依托泊苷[M+NH4]+,606/229.结果 替尼泊苷和内标依托泊苷的保留时间分别在2.7和2.2 min,替尼泊苷的线性范围为3~300 μg·L-1.提取回收率大于75%,方法回收率大于90%,日内,日间RSD<10%(n=5).结论 本试验方法简便快速,适用于替尼泊苷体液的浓度测定,利于新药临床研究.

  20. P60WHY ANIMAL MODELS OF GENE THERAPY HAVE LET GLIOMA PATIENTS DOWN

    Science.gov (United States)

    Hirst, Theodore C.; Vesterinen, Hanna M.; Conlin, Samantha; Egan, Kieren J.; Antonic, Ana; McLean, Aaron Lawson; Macleod, Malcolm R.; Whittle, Ian R.; Grant, Robin; Brennan, Paul M.; Sena, Emily S.

    2014-01-01

    INTRODUCTION: The development of new therapeutics is often characterised by promising animal research that fails to translate into clinical efficacy; this holds for the development of gene therapy in glioma. We set out to test the hypothesis that this is because of limitations in the internal and external validity of studies reporting the use of gene therapy in rodent models of glioma. METHOD: We systematically identified studies testing gene therapy in rodent glioma models by searching three online databases. The number of animals treated and median survival were extracted and studies graded using a 9-point quality checklist. We calculated median survival ratios and used random effects meta-analysis to provide estimates of efficacy. We explored the effects of study design and quality and searched for evidence of publication bias. RESULTS: We found 194 publications using gene therapy in experimental glioma, describing 427 experiments involving 6366 animals. Overall, genetherapy improved median survival by 1.60 fold (95%CI 1.53-1.67). Study quality was low and the type of gene therapy did not account for observed differences in outcome. Study design characteristics accounted for a significant proportion of between-study heterogeneity and we observedsimilar findings in a subset of data limited to the most common genetherapy. CONCLUSION: As the dysregulation of key molecular pathways is characteristic of gliomas, gene therapy remains a promising treatment forglioma. Nevertheless, we have identified areas for improvement in conduct and reporting of such studies. Further work should focus on genes of interest in paradigms that recapitulate human disease. This may improve the translation of such therapies into the clinic.

  1. A variable age of onset segregation model for linkage analysis, with correction for ascertainment, applied to glioma

    DEFF Research Database (Denmark)

    Sun, Xiangqing; Vengoechea, Jaime; Elston, Robert

    2012-01-01

    We propose a 2-step model-based approach, with correction for ascertainment, to linkage analysis of a binary trait with variable age of onset and apply it to a set of multiplex pedigrees segregating for adult glioma.......We propose a 2-step model-based approach, with correction for ascertainment, to linkage analysis of a binary trait with variable age of onset and apply it to a set of multiplex pedigrees segregating for adult glioma....

  2. Experimental nodel of C6 brain tumors in athymic rats Modelo experimental de tumor cerebral C6 em ratos atímicos

    Directory of Open Access Journals (Sweden)

    Flávio K. Miura

    2008-06-01

    Full Text Available Malignant brain tumor experimental models tend to employ cells that are immunologically compatible with the receptor animal. In this study, we have proposed an experimental model of encephalic tumor development by injecting C6 cells into athymic Rowett rats, aiming at reaching a model which more closely resembles to the human glioma tumor. In our model, we observed micro-infiltration of tumor cell clusters in the vicinity of the main tumor mass, and of more distal isolated tumor cells immersed in normal encephalic parenchyma. This degree of infiltration is superior to that usually observed in other C6 models.Modelos experimentais de tumores cerebrais malignos geralmente utilizam células imunologicamente compatíveis com o animal receptor. Neste estudo apresentamos um modelo experimental baseado na inoculação de células C6 em ratos atímicos Rowett, visando obter um tumor que se assemelhe mais àqueles observados nos seres humanos. Neste modelo observamos microinfiltração de ilhotas de células na periferia da massa tumoral principal e nas áreas mais distantes, células tumorais isoladas no tecido cerebral normal. Este grau de infiltração é superior àquele observado em outros modelos utilizando as células C6.

  3. Polarizabilities and van der Waals C6 coefficients of fullerenes from an atomistic electrodynamics model: Anomalous scaling with number of carbon atoms

    Science.gov (United States)

    Saidi, Wissam A.; Norman, Patrick

    2016-07-01

    The van der Waals C6 coefficients of fullerenes are shown to exhibit an anomalous dependence on the number of carbon atoms N such that C6 ∝ N2.2 as predicted using state-of-the-art quantum mechanical calculations based on fullerenes with small sizes, and N2.75 as predicted using a classical-metallic spherical-shell approximation of the fullerenes. We use an atomistic electrodynamics model where each carbon atom is described by a polarizable object to extend the quantum mechanical calculations to larger fullerenes. The parameters of this model are optimized to describe accurately the static and complex polarizabilities of the fullerenes by fitting against accurate ab initio calculations. This model shows that C6 ∝ N2.8, which is supportive of the classical-metallic spherical-shell approximation. Additionally, we show that the anomalous dependence of the polarizability on N is attributed to the electric charge term, while the dipole-dipole term scales almost linearly with the number of carbon atoms.

  4. Polarizabilities and van der Waals C6 coefficients of fullerenes from an atomistic electrodynamics model: Anomalous scaling with number of carbon atoms.

    Science.gov (United States)

    Saidi, Wissam A; Norman, Patrick

    2016-07-14

    The van der Waals C6 coefficients of fullerenes are shown to exhibit an anomalous dependence on the number of carbon atoms N such that C6 ∝ N(2.2) as predicted using state-of-the-art quantum mechanical calculations based on fullerenes with small sizes, and N(2.75) as predicted using a classical-metallic spherical-shell approximation of the fullerenes. We use an atomistic electrodynamics model where each carbon atom is described by a polarizable object to extend the quantum mechanical calculations to larger fullerenes. The parameters of this model are optimized to describe accurately the static and complex polarizabilities of the fullerenes by fitting against accurate ab initio calculations. This model shows that C6 ∝ N(2.8), which is supportive of the classical-metallic spherical-shell approximation. Additionally, we show that the anomalous dependence of the polarizability on N is attributed to the electric charge term, while the dipole-dipole term scales almost linearly with the number of carbon atoms.

  5. A Novel Mouse Model of Diffuse Intrinsic Pontine Glioma Initiated in Pax3-Expressing Cells

    Directory of Open Access Journals (Sweden)

    Katherine L. Misuraca

    2016-01-01

    Full Text Available Diffuse intrinsic pontine glioma (DIPG is a rare and incurable brain tumor that arises predominately in children and involves the pons, a structure that along with the midbrain and medulla makes up the brainstem. We have previously developed genetically engineered mouse models of brainstem glioma using the RCAS/Tv-a system by targeting PDGF-B overexpression, p53 loss, and H3.3K27M mutation to Nestin-expressing brainstem progenitor cells of the neonatal mouse. Here we describe a novel mouse model targeting these same genetic alterations to Pax3-expressing cells, which in the neonatal mouse pons consist of a Pax3+/Nestin+/Sox2+ population lining the fourth ventricle and a Pax3+/NeuN+ parenchymal population. Injection of RCAS-PDGF-B into the brainstem of Pax3-Tv-a mice at postnatal day 3 results in 40% of mice developing asymptomatic low-grade glioma. A mixture of low- and high-grade glioma results from injection of Pax3-Tv-a;p53fl/fl mice with RCAS-PDGF-B and RCAS-Cre, with or without RCAS-H3.3K27M. These tumors are Ki67+, Nestin+, Olig2+, and largely GFAP− and can arise anywhere within the brainstem, including the classic DIPG location of the ventral pons. Expression of the H3.3K27M mutation reduces overall H3K27me3 as compared with tumors without the mutation, similar to what has been previously shown in human and mouse tumors. Thus, we have generated a novel genetically engineered mouse model of DIPG, which faithfully recapitulates the human disease and represents a novel platform with which to study the biology and treatment of this deadly disease.

  6. Myxoma virus virotherapy for glioma in immunocompetent animal models: optimizing administration routes and synergy with rapamycin.

    Science.gov (United States)

    Lun, XueQing; Alain, Tommy; Zemp, Franz J; Zhou, Hongyuan; Rahman, Masmudur M; Hamilton, Mark G; McFadden, Grant; Bell, John; Senger, Donna L; Forsyth, Peter A

    2010-01-15

    Oncolytic myxoma virus (MYXV) is being developed as a novel virotherapeutic against human brain cancer and has promising activity against human brain tumor models in immunocompromised hosts. Because an intact immune system could reduce its efficacy, the purpose of this study was to evaluate the oncolytic potential of MYXV in immunocompetent racine glioma models. Here, we report that MYXV infects and kills all racine cell glioma lines and that its effects are enhanced by rapamycin. Intratumoral administration of MYXV with rapamycin improved viral replication in the tumor and significantly prolonged host survival. Similarly, coadministration via a method of convection-enhanced delivery (CED) enhanced viral replication and efficacy in vivo. Mechanisms by which rapamycin improved MYXV oncolysis included an inhibition of type I IFN production in vitro and a reduction of intratumoral infiltration of CD68(+) microglia/macrophages and CD163(+) macrophages in vivo. Our findings define a method to improve MYXV efficacy against gliomas by rapamycin coadministration, which acts to promote immune responses engaged by viral delivery.

  7. A Truncated form of CD200 (CD200S Expressed on Glioma Cells Prolonged Survival in a Rat Glioma Model by Induction of a Dendritic Cell-Like Phenotype in Tumor-Associated Macrophages

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    Kana Kobayashi

    2016-04-01

    Full Text Available CD200 induces immunosuppression in myeloid cells expressing its receptor CD200R, which may have consequences for tumor immunity. We found that human carcinoma tissues express not only full-length CD200 (CD200L but also its truncated form, CD200S. Although CD200S is reported to antagonize the immunosuppressive actions of CD200L, the role of CD200S in tumor immunity has never been investigated. We established rat C6 glioma cell lines that expressed either CD200L or CD200S; the original C6 cell line did not express CD200 molecules. The cell lines showed no significant differences in growth. Upon transplantation into the neonatal Wistar rat forebrain parenchyma, rats transplanted with C6-CD200S cells survived for a significantly longer period than those transplanted with the original C6 and C6-CD200L cells. The C6-CD200S tumors were smaller than the C6-CD200L or C6-original tumors, and many apoptotic cells were found in the tumor cell aggregates. Tumor-associated macrophages (TAMs in C6-CD200S tumors displayed dendritic cell (DC-like morphology with multiple processes and CD86 expression. Furthermore, CD3+, CD4+ or CD8+ cells were more frequently found in C6-CD200S tumors, and the expression of DC markers, granzyme, and perforin was increased in C6-CD200S tumors. Isolated TAMs from original C6 tumors were co-cultured with C6-CD200S cells and showed increased expression of DC markers. These results suggest that CD200S activates TAMs to become DC-like antigen presenting cells, leading to the activation of CD8+ cytotoxic T lymphocytes, which induce apoptotic elimination of tumor cells. The findings on CD200S action may provide a novel therapeutic modality for the treatment of carcinomas.

  8. Endothelial progenitor cells (EPCs as gene carrier system for rat model of human glioma.

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    Nadimpalli Ravi S Varma

    Full Text Available BACKGROUND: Due to their unique property to migrate to pathological lesions, stem cells are used as a delivery vehicle for therapeutic genes to tumors, especially for glioma. It is critically important to track the movement, localization, engraftment efficiency and functional capability or expression of transgenes of selected cell populations following transplantation. The purposes of this study were to investigate whether 1 intravenously administered, genetically transformed cord blood derived EPCs can carry human sodium iodide symporter (hNIS to the sites of tumors in rat orthotopic model of human glioma and express transgene products, and 2 whether accumulation of these administered EPCs can be tracked by different in vivo imaging modalities. METHODS AND RESULTS: Collected EPCs were cultured and transduced to carry hNIS. Cellular viability, differential capacity and Tc-99m uptake were determined. Five to ten million EPCs were intravenously administered and Tc-99-SPECT images were acquired on day 8, to determine the accumulation of EPCs and expression of transgenes (increase activity of Tc-99m in the tumors. Immunohistochemistry was performed to determine endothelial cell markers and hNIS positive cells in the tumors. Transduced EPCs were also magnetically labeled and accumulation of cells was confirmed by MRI and histochemistry. SPECT analysis showed increased activity of Tc-99m in the tumors that received transduced EPCs, indicative of the expression of transgene (hNIS. Activity of Tc-99m in the tumors was also dependent on the number of administered transduced EPCs. MRI showed the accumulation of magnetically labeled EPCs. Immunohistochemical analysis showed iron and hNIS positive and, human CD31 and vWF positive cells in the tumors. CONCLUSION: EPC was able to carry and express hNIS in glioma following IV administration. SPECT detected migration of EPCs and expression of the hNIS gene. EPCs can be used as gene carrier/delivery system for

  9. On a minimal model for hemodynamics and metabolism of lactate: application to low grade glioma and therapeutic strategies.

    Science.gov (United States)

    Lahutte-Auboin, Marion; Guillevin, Rémy; Françoise, Jean-Pierre; Vallée, Jean-Noël; Costalat, Robert

    2013-03-01

    WHO II low grade glioma evolves inevitably to anaplastic transformation. Magnetic resonance imaging is a good non-invasive way to watch it, by hemodynamic and metabolic modifications, thanks to multinuclear spectroscopy (1)H/(31)P. In this work we study a multi-scale minimal model of hemodynamics and metabolism applied to the study of gliomas. This mathematical analysis leads us to a fast-slow system. The control of the position of the stationary point brings to the concept of domain of viability. Starting from this system, the equations bring to light the parameters that push glioma cells out of their domain of viability. Four fundamental factors are highlighted. The first two are cerebral blood flow and the rate of lactate transport through monocarboxylate transporters, which must be reduced in order to push glioma out of its domain of viability. Another factor is the intra arterial lactate, which must be increased. The last factor is pH, indeed a decrease of intra cellular pH could interfere with glioma growth. These reflections suggest that these four parameters could lead to new therapeutic strategies for the management of low grade gliomas.

  10. Conceptual OOP design of Pilot Code for Two-Fluid, Three-field Model with C++ 6.0

    Energy Technology Data Exchange (ETDEWEB)

    Chung, B. D.; Lee, Y. J

    2006-09-15

    To establish the concept of the objective oriented program (OOP) design for reactor safety analysis code, the preliminary OOP design for PILOT code, which based on one dimensional two fluid three filed model, has been attempted with C++ language feature. Microsoft C++ language has been used since it is available as groupware utilization in KAERI. The language has can be merged with Compac Visual Fortran 6.6 in Visual Studio platform. In the development platform, C++ has been used as main language and Fortran has been used as mixed language in connection with C++ main drive program. The mixed language environment is a specific feature provided in visual studio. Existing Fortran source was utilized for input routine of reading steam table from generated file and routine of steam property calculation. The calling convention and passing argument from C++ driver was corrected. The mathematical routine, such as inverse matrix conversion and tridiagonal matrix solver, has been used as PILOT Fortran routines. Simple volume and junction utilized in PILOT code can be treated as objects, since they are the basic construction elements of code system. Other routines for overall solution scheme have been realized as procedure C functions. The conceptual design which consists of hydraulic loop, component, volume, and junction class has been described in the appendix in order to give the essential OOP structure of system safety analysis code. The attempt shows that many part of system analysis code can be expressed as objects, although the overall structure should be maintained as procedure functions. The encapsulation of data and functions within an object can provide many beneficial aspects in programming of system code.

  11. Multiple Gliomas

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Multiple gliomas are well-recognized but uncommon tumors. The incidence of multiple gliomas according to some reports ranges from 0.5% to 20% of all gliomas diagnosed. Multiple gliomas can be divided into two categories. One is by location of the lesions (multifocal and multicentric). The second type is by the time of the lesions occur (synchronous and metachronous). The lesions generally show hypo, or isodensity on CT; a hypo- or isointense signal on T1-weighted images, and a hyperintense signal on T2-weighted images. Glioblastoma is the most frequent histotype. The prognosis of multiple gliomas remains unfavorable. The treatment of multiple gliomas includes surgery, radiotherapy and chemotherapy. Distinction between multicentric and multifocal gliomas is difficult. This report reviews in detail the aspects of multiple gliomas mentioned above.

  12. Cascades in model steels: The effect of cementite (Fe3C) and Cr23C6 particles on short-term crystal damage

    Science.gov (United States)

    Henriksson, K. O. E.

    2015-06-01

    Ferritic stainless steel can be modeled as an iron matrix containing precipitates of cementite (Fe3C) and Cr23C6. When used in nuclear power production the steels in the vicinity of the core start to accumulate damage due to neutrons. The role of the afore-mentioned carbides in this process is not well understood. In order to clarify the situation bulk cascades created by primary recoils in model steels have been carried out in the present work. Investigated configurations consisted of bulk ferrite containing spherical particles (diameter of 4 nm) of either (1) Fe3C or (2) Cr23C6. Primary recoils were initiated at different distances from the inclusions, with recoil energies varying between 100 eV and 1 keV. Results for the number of point defects such as vacancies and antisites are presented. These findings indicate that defects are also remaining when cascades are started outside the carbide inclusions. The work uses a recently developed Abell-Brenner-Tersoff potential for the Fe-Cr-C system.

  13. Quercetin derivative induces cell death in glioma cells by modulating NF-κB nuclear translocation and caspase-3 activation.

    Science.gov (United States)

    Kiekow, Cíntia J; Figueiró, Fabrício; Dietrich, Fabrícia; Vechia, Luciana Dalla; Pires, Elisa N S; Jandrey, Elisa H F; Gnoatto, Simone C B; Salbego, Christianne G; Battastini, Ana Maria O; Gosmann, Grace

    2016-03-10

    Treated glioblastoma multiforme (GBM) patients only survive 6 to 14months after diagnosis; therefore, the development of novel therapeutic strategies to treat gliomas remains critically necessary. Considering that phenolic compounds, like quercetin, have the potential to be used in the chemotreatment of gliomas and that some flavonoids exhibit the ability to cross the BBB, in the present study, we investigated the antitumor effect of flavonoids (including chalcones, flavones, flavanones and flavonols). Initially their activities were tested in C6 glioma cells screened using the MTT method, resulting in the selection of chalcone 2 whose feasibility was confirmed by a Trypan Blue exclusion assay in the low μM range on C6 glioma cells. Cell cycle and apoptotic death analyses on C6 glioma cells were also performed, and chalcone 2 increased the apoptosis of the cells but did not alter the cell cycle progression. In addition, treatments with these two compounds were not cytotoxic to hippocampal organotypic cultures, a model of healthy neural cells. Furthermore, the results indicated that 2 induced apoptosis by inhibition of NF-κB and activation of active caspase-3 in glioma cells, suggesting that it is a potential prototype to develop new treatments for GBM in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Characterization of highly proliferative secondary tumor clusters along host blood vessels in malignant glioma.

    Science.gov (United States)

    Wang, Ting-Chung; Cheng, Chun-Yu; Yang, Wei-Hsun; Chen, Wen-Cheng; Chang, Pey-Jium

    2015-11-01

    The aim of the present study was to investigate the extensive invasion of tumor cells into normal brain tissue, a life‑threatening feature of malignant gliomas. How invasive tumor cells migrate into normal brain tissue and form a secondary tumor structure remains to be elucidated. In the present study, the morphological and phenotypic changes of glioma cells during invasion in a C6 glioma model were investigated. C6 glioma cells were stereotactically injected into the right putamen region of adult Sprague‑Dawley rats. The brain tissue sections were then subjected to hematoxylin and eosin, immunohistochemical or immunofluorescent staining. High magnification views of the tissue sections revealed that C6 cells formed tumor spheroids following implantation and marked invasion was observed shortly after spheroid formation. In the later stages of invasion, certain tumor cells invaded the perivascular space and formed small tumor clusters. These small tumor clusters exhibited certain common features, including tumor cell multilayers surrounding an arteriole, which occurred up to several millimeters away from the primary tumor mass; a high proliferation rate; and similar gene expression profiles to the primary tumor. In conclusion, the present study revealed that invading tumor cells are capable of forming highly proliferative cell clusters along arterioles near the tumor margin, which may be a possible cause of the recurrence of malignant glioma.

  15. Establishment of 9L/F344 rat intracerebral glioma model of brain tumor stem cells

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    Zong-yu XIAO

    2015-04-01

    Full Text Available Objective To establish the 9L/F344 rat intracerebral glioma model of brain tumor stem cells.  Methods Rat 9L gliosarcoma stem-like cells were cultured in serum-free suspension. The expression of CD133 and nestin were tested by immunohistochemistry. A total of 48 inbredline male F344 rats were randomly divided into 2 groups, and 9L tumor sphere cells and 9L monolayer cells were respectively implanted into the right caudate nucleus of F344 rats in 2 groups. Survival time was observed and determined using the method of Kaplan-Meier survival analysis. Fourteen days after implantation or when the rats were dying, their brains were perfused and sectioned for HE staining, and CD133 and nestin were detected by immunohistochemistry.  Results Rat 9L tumor spheres were formed with suspension culture in serum-free medium. The gliomas formed in both groups were invasive without obvious capsule. More new vessels, bleeding and necrosis could be detected in 9L tumor spheres group. The tumor cells in both groups were positive for CD133 and nestin. There was no significant difference in the expression of CD133 and nestin between 2 groups (P > 0.05, for all. According to the expression of nestin, the tumors formed by 9L tumor sphere cells were more invasive. The median survival time of the rats bearing 9L tumor sphere cells was 15 d (95%CI: 15.219-15.781, and the median survival time of the rats bearing 9L monolayer cells was 21 d (95%CI: 20.395-21.605. There was significant difference between 2 groups (χ2 = 12.800, P = 0.000.  Conclusions 9L/F344 rat intracerebral glioma model of brain tumor stem cells is successfully established, which provides a glioma model for the future research. DOI: 10.3969/j.issn.1672-6731.2015.04.012

  16. Canine spontaneous glioma: a translational model system for convection-enhanced delivery.

    Science.gov (United States)

    Dickinson, Peter J; LeCouteur, Richard A; Higgins, Robert J; Bringas, John R; Larson, Richard F; Yamashita, Yoji; Krauze, Michal T; Forsayeth, John; Noble, Charles O; Drummond, Daryl C; Kirpotin, Dmitri B; Park, John W; Berger, Mitchel S; Bankiewicz, Krystof S

    2010-09-01

    Canine spontaneous intracranial tumors bear striking similarities to their human tumor counterparts and have the potential to provide a large animal model system for more realistic validation of novel therapies typically developed in small rodent models. We used spontaneously occurring canine gliomas to investigate the use of convection-enhanced delivery (CED) of liposomal nanoparticles, containing topoisomerase inhibitor CPT-11. To facilitate visualization of intratumoral infusions by real-time magnetic resonance imaging (MRI), we included identically formulated liposomes loaded with Gadoteridol. Real-time MRI defined distribution of infusate within both tumor and normal brain tissues. The most important limiting factor for volume of distribution within tumor tissue was the leakage of infusate into ventricular or subarachnoid spaces. Decreased tumor volume, tumor necrosis, and modulation of tumor phenotype correlated with volume of distribution of infusate (Vd), infusion location, and leakage as determined by real-time MRI and histopathology. This study demonstrates the potential for canine spontaneous gliomas as a model system for the validation and development of novel therapeutic strategies for human brain tumors. Data obtained from infusions monitored in real time in a large, spontaneous tumor may provide information, allowing more accurate prediction and optimization of infusion parameters. Variability in Vd between tumors strongly suggests that real-time imaging should be an essential component of CED therapeutic trials to allow minimization of inappropriate infusions and accurate assessment of clinical outcomes.

  17. Rabbit Model of Human Gliomas: Implications for Intra-Arterial Drug Delivery

    Science.gov (United States)

    Qin, Huamin; Janowski, Miroslaw; Pearl, Monica S.; Malysz-Cymborska, Izabela; Li, Shen; Eberhart, Charles G.

    2017-01-01

    The prognosis for malignant brain tumors remains poor despite a combination of surgery, radiotherapy, and chemotherapy. This is partly due to the blood-brain barrier, a major obstacle that prevents therapeutic agents from effectively reaching the tumor. We have recently developed a method for precise and predictable opening of the blood-brain barrier via the intra-arterial administration of mannitol, a hyperosmolar agent, in a rabbit model, whose vascular anatomy facilitates the use of standard interventional neuroradiology techniques and devices. To date, however, no protocols are available that enable human glioma modeling in rabbits. In this article, we report on the xenotransplantation of a human glioblastoma (GBM-1) in adult New Zealand rabbits. We induced multi-drug immunosuppression (Mycophenolate Mofetil, Dexamethasone, Tacrolimus) and stereotactically implanted GBM-1 tumor cells into rabbit brains. The rabbits were followed for 42 days, monitored by MRI and body weight measurements, and underwent postmortem histopathological analysis. On MRI, brain tumors were identified on T2-weighted scans. On histopathology, tumors were detected with hematoxylin/eosin and their human origin was confirmed with immunohistochemistry against human-specific antigens. Our method for human glioma modeling in rabbits provides the foundation to test novel treatment strategies, including intra-arterial therapeutic agent delivery. PMID:28103265

  18. Nanoshell-mediated photothermal therapy improves survival in a murine glioma model.

    Science.gov (United States)

    Day, Emily S; Thompson, Patrick A; Zhang, Linna; Lewinski, Nastassja A; Ahmed, Nabil; Drezek, Rebekah A; Blaney, Susan M; West, Jennifer L

    2011-08-01

    We are developing a novel treatment for high-grade gliomas using near infrared-absorbing silica-gold nanoshells that are thermally activated upon exposure to a near infrared laser, thereby irreversibly damaging cancerous cells. The goal of this work was to determine the efficacy of nanoshell-mediated photothermal therapy in vivo in murine xenograft models. Tumors were induced in male IcrTac:ICR-Prkdc(SCID) mice by subcutaneous implantation of Firefly Luciferase-labeled U373 human glioma cells and biodistribution and survival studies were performed. To evaluate nanoparticle biodistribution, nanoshells were delivered intravenously to tumor-bearing mice and after 6, 24, or 48 h the tumor, liver, spleen, brain, muscle, and blood were assessed for gold content by inductively coupled plasma-mass spectrometry (ICP-MS) and histology. Nanoshell concentrations in the tumor increased for the first 24 h and stabilized thereafter. Treatment efficacy was evaluated by delivering saline or nanoshells intravenously and externally irradiating tumors with a near infrared laser 24 h post-injection. Success of treatment was assessed by monitoring tumor size, tumor luminescence, and survival time of the mice following laser irradiation. There was a significant improvement in survival for the nanoshell treatment group versus the control (P nanoshell treatment group remained tumor free at the end of the 90-day study period. By comparison, none of the mice in the control group survived beyond 24 days and mean survival was only 13.3 days. The results of these studies suggest that nanoshell-mediated photothermal therapy represents a promising novel treatment strategy for malignant glioma.

  19. T11TS inhibits Angiopoietin-1/Tie-2 signaling, EGFR activation and Raf/MEK/ERK pathway in brain endothelial cells restraining angiogenesis in glioma model.

    Science.gov (United States)

    Bhattacharya, Debanjan; Chaudhuri, Suhnrita; Singh, Manoj Kumar; Chaudhuri, Swapna

    2015-06-01

    Malignant gliomas represent one of the most aggressive and hypervascular primary brain tumors. Angiopoietin-1, the peptide growth factor activates endothelial Tie-2 receptor promoting vessel maturation and vascular stabilization steps of angiogenesis in glioma. Epidermal growth factor receptor (EGFR) and Tie-2 receptor on endothelial cells once activated transmits signals through downstream Raf/MEK/ERK pathway promoting endothelial cell proliferation and migration which are essential for angiogenesis induction. The in vivo effect of sheep erythrocyte membrane glycopeptide T11-target structure (T11TS) on angiopoietin-1/Tie-2 axis, EGFR signaling and Raf/MEK/ERK pathway in glioma associated endothelial cells has not been investigated previously. The present study performed with rodent glioma model aims to investigate the effect of T11TS treatment on angiopoietin-1/Tie-2 signaling, EGFR activity and Raf/MEK/ERK pathway in glioma associated endothelial cells within glioma milieu. T11TS administration in rodent glioma model inhibited angiopoietin-1 expression and attenuated Tie-2 expression and activation in glioma associated brain endothelial cells. T11TS treatment also downregulated total and phosphorylated EGFR expression in glioma associated endothelial cells. Additionally T11TS treatment inhibited Raf-1 expression, MEK-1 and ERK-1/2 expression and phosphorylation in glioma associated brain endothelial cells. Thus T11TS therapy remarkably inhibits endothelial angiopoietin-1/Tie-2 signaling associated with vessel maturation and simultaneously antagonizes endothelial cell proliferation signaling by blocking EGFR activation and components of Raf/MEK/ERK pathway. Collectively, the findings demonstrate a multi-targeted anti-angiogenic activity of T11TS which augments the potential for clinical translation of T11TS as an effective angiogenesis inhibitor for glioma treatment.

  20. Relative contributions of strain-dependent permeability and fixed charged density of proteoglycans in predicting cervical disc biomechanics: a poroelastic C5-C6 finite element model study.

    Science.gov (United States)

    Hussain, Mozammil; Natarajan, Raghu N; Chaudhary, Gulafsha; An, Howard S; Andersson, Gunnar B J

    2011-05-01

    Disc swelling pressure (P(swell)) facilitated by fixed charged density (FCD) of proteoglycans (P(fcd)) and strain-dependent permeability (P(strain)) are of critical significance in the physiological functioning of discs. FCD of proteoglycans prevents any excessive matrix deformation by tissue stiffening, whereas strain-dependent permeability limits the rate of stress transfer from fluid to solid skeleton. To date, studies involving the modeling of FCD of proteoglycans and strain-dependent permeability have not been reported for the cervical discs. The current study objective is to compare the relative contributions of strain-dependent permeability and FCD of proteoglycans in predicting cervical disc biomechanics. Three-dimensional finite element models of a C5-C6 segment with three different disc compositions were analyzed: an SPFP model (strain-dependent permeability and FCD of proteoglycans), an SP model (strain-dependent permeability alone), and an FP model (FCD of proteoglycans alone). The outcomes of the current study suggest that the relative contributions of strain-dependent permeability and FCD of proteoglycans were almost comparable in predicting the physiological behavior of the cervical discs under moment loads. However, under compression, strain-dependent permeability better predicted the in vivo disc response than that of the FCD of proteoglycans. Unlike the FP model (least stiff) in compression, motion behavior of the three models did not vary much from each other and agreed well within the standard deviations of the corresponding in vivo published data. Flexion was recorded with maximum P(fcd) and P(strain), whereas minimum values were found in extension. The study data enhance the understanding of the roles played by the FCD of proteoglycans and strain-dependent permeability and porosity in determining disc tissue swelling behavior. Degenerative changes involving strain-dependent permeability and/or loss of FCD of proteoglycans can further be

  1. Mathematical modeling of human glioma growth based on brain topological structures: study of two clinical cases.

    Directory of Open Access Journals (Sweden)

    Cecilia Suarez

    Full Text Available Gliomas are the most common primary brain tumors and yet almost incurable due mainly to their great invasion capability. This represents a challenge to present clinical oncology. Here, we introduce a mathematical model aiming to improve tumor spreading capability definition. The model consists in a time dependent reaction-diffusion equation in a three-dimensional spatial domain that distinguishes between different brain topological structures. The model uses a series of digitized images from brain slices covering the whole human brain. The Talairach atlas included in the model describes brain structures at different levels. Also, the inclusion of the Brodmann areas allows prediction of the brain functions affected during tumor evolution and the estimation of correlated symptoms. The model is solved numerically using patient-specific parametrization and finite differences. Simulations consider an initial state with cellular proliferation alone (benign tumor, and an advanced state when infiltration starts (malign tumor. Survival time is estimated on the basis of tumor size and location. The model is used to predict tumor evolution in two clinical cases. In the first case, predictions show that real infiltrative areas are underestimated by current diagnostic imaging. In the second case, tumor spreading predictions were shown to be more accurate than those derived from previous models in the literature. Our results suggest that the inclusion of differential migration in glioma growth models constitutes another step towards a better prediction of tumor infiltration at the moment of surgical or radiosurgical target definition. Also, the addition of physiological/psychological considerations to classical anatomical models will provide a better and integral understanding of the patient disease at the moment of deciding therapeutic options, taking into account not only survival but also life quality.

  2. Transcriptional network analysis reveals that AT1 and AT2 angiotensin II receptors are both involved in the regulation of genes essential for glioma progression.

    Science.gov (United States)

    Azevedo, Hátylas; Fujita, André; Bando, Silvia Yumi; Iamashita, Priscila; Moreira-Filho, Carlos Alberto

    2014-01-01

    Gliomas are aggressive primary brain tumors with high infiltrative potential. The expression of Angiotensin II (Ang II) receptors has been associated with poor prognosis in human astrocytomas, the most common type of glioma. In this study, we investigated the role of Angiotensin II in glioma malignancy through transcriptional profiling and network analysis of cultured C6 rat glioma cells exposed to Ang II and to inhibitors of its membrane receptor subtypes. C6 cells were treated with Ang II and specific antagonists of AT1 and AT2 receptors. Total RNA was isolated after three and six hours of Ang II treatment and analyzed by oligonucleotide microarray technology. Gene expression data was evaluated through transcriptional network modeling to identify how differentially expressed (DE) genes are connected to each other. Moreover, other genes co-expressing with the DE genes were considered in these analyses in order to support the identification of enriched functions and pathways. A hub-based network analysis showed that the most connected nodes in Ang II-related networks exert functions associated with cell proliferation, migration and invasion, key aspects for glioma progression. The subsequent functional enrichment analysis of these central genes highlighted their participation in signaling pathways that are frequently deregulated in gliomas such as ErbB, MAPK and p53. Noteworthy, either AT1 or AT2 inhibitions were able to down-regulate different sets of hub genes involved in protumoral functions, suggesting that both Ang II receptors could be therapeutic targets for intervention in glioma. Taken together, our results point out multiple actions of Ang II in glioma pathogenesis and reveal the participation of both Ang II receptors in the regulation of genes relevant for glioma progression. This study is the first one to provide systems-level molecular data for better understanding the protumoral effects of Ang II in the proliferative and infiltrative behavior of

  3. Transcriptional network analysis reveals that AT1 and AT2 angiotensin II receptors are both involved in the regulation of genes essential for glioma progression.

    Directory of Open Access Journals (Sweden)

    Hátylas Azevedo

    Full Text Available Gliomas are aggressive primary brain tumors with high infiltrative potential. The expression of Angiotensin II (Ang II receptors has been associated with poor prognosis in human astrocytomas, the most common type of glioma. In this study, we investigated the role of Angiotensin II in glioma malignancy through transcriptional profiling and network analysis of cultured C6 rat glioma cells exposed to Ang II and to inhibitors of its membrane receptor subtypes. C6 cells were treated with Ang II and specific antagonists of AT1 and AT2 receptors. Total RNA was isolated after three and six hours of Ang II treatment and analyzed by oligonucleotide microarray technology. Gene expression data was evaluated through transcriptional network modeling to identify how differentially expressed (DE genes are connected to each other. Moreover, other genes co-expressing with the DE genes were considered in these analyses in order to support the identification of enriched functions and pathways. A hub-based network analysis showed that the most connected nodes in Ang II-related networks exert functions associated with cell proliferation, migration and invasion, key aspects for glioma progression. The subsequent functional enrichment analysis of these central genes highlighted their participation in signaling pathways that are frequently deregulated in gliomas such as ErbB, MAPK and p53. Noteworthy, either AT1 or AT2 inhibitions were able to down-regulate different sets of hub genes involved in protumoral functions, suggesting that both Ang II receptors could be therapeutic targets for intervention in glioma. Taken together, our results point out multiple actions of Ang II in glioma pathogenesis and reveal the participation of both Ang II receptors in the regulation of genes relevant for glioma progression. This study is the first one to provide systems-level molecular data for better understanding the protumoral effects of Ang II in the proliferative and infiltrative

  4. Mol 7C/6; Mol 7C/6

    Energy Technology Data Exchange (ETDEWEB)

    Aberle, J.; Schleisiek, K.; Schmuck, I.; Schmidt, L.; Romer, O.; Weih, G.

    1995-08-01

    The Mol 7C/6 coolant blockage experiment in the Belgian BR2 reactor yielded results different from Mol 7C experiments with low burnup pins: At 10% burnup local failure is not self-limiting, but requires active systems for detection and scram. The Mol 7C series was finished in 1991. In each of the test bundles Mol 7C/4, /5 and /6, 30 Mk I pins pre-irradiated in KNK II were used. The central blockage consisted of enriched UO{sub 2} covering 30 percent of the bundle cross-section, with a height of 40 mm. The most important system for timely detection of coolant blockages of the type studied in Mol 7C/6 is based on DND. (orig.)

  5. Inhibition of autophagy induced by quercetin at a late stage enhances cytotoxic effects on glioma cells.

    Science.gov (United States)

    Bi, Yunke; Shen, Chen; Li, Chenguang; Liu, Yaohua; Gao, Dandan; Shi, Chen; Peng, Fei; Liu, Zhendong; Zhao, Boxian; Zheng, Zhixing; Wang, Xiaoxiong; Hou, Xu; Liu, Huailei; Wu, Jianing; Zou, Huichao; Wang, Kaikai; Zhong, Chen; Zhang, Jiakang; Shi, Changbin; Zhao, Shiguang

    2016-03-01

    Glioma is the most common primary brain tumor in the central nervous system (CNS) with high morbidity and mortality in adults. Although standardized comprehensive therapy has been adapted, the prognosis of glioma patients is still frustrating and thus novel therapeutic strategies are urgently in need. Quercetin (Quer), an important flavonoid compound found in many herbs, is shown to be effective in some tumor models including glioma. Recently, it is reported that adequate regulation of autophagy can strengthen cytotoxic effect of anticancer drugs. However, it is not yet fully clear how we should modulate autophagy to achieve a satisfactory therapeutic effect. 3-Methyladenine (3-MA) and Beclin1 short hairpin RNA (shRNA) were used to inhibit the early stage of autophage while chloroquine (CQ) to inhibit the late stage. MTT assay was implemented to determine cell viability. Transmission electron microscopy, western blot, and immunohistochemistry were adopted to evaluate autophagy. Western blot, flow cytometry, and immunohistochemistry were used to detect apoptosis. C6 glioma xenograft models were established to assess the therapeutic effect (the body weight change, the median survival time, and tumor volume) in vivo. Quercetin can inhibit cell viability and induce autophagy of U87 and U251 glioma cells in a dose-dependent manner. Inhibition of early-stage autophagy by 3-MA or shRNA against Beclin1 attenuated the quercetin-induced cytotoxicity. In contrast, suppression of autophagy at a late stage by CQ enhanced the anti-glioma efficiency of quercetin. Therapeutic effect of quercetin for malignant glioma can be strengthened by inhibition of autophagy at a late stage, not initial stage, which may provide a novel opportunity for glioma therapy.

  6. Assessment of Tumor Cells in a Mouse Model of Diffuse Infiltrative Glioma by Raman Spectroscopy

    Directory of Open Access Journals (Sweden)

    Kuniaki Tanahashi

    2014-01-01

    Full Text Available Glioma of infiltrative nature is challenging for surgeons to achieve tumor-specific and maximal resection. Raman spectroscopy provides structural information on the targeted materials as vibrational shifts. We utilized Raman spectroscopy to distinguish invasive tumors from normal tissues. Spectra obtained from replication-competent avian sarcoma-(RCAS- based infiltrative glioma cells and glioma tissues (resembling low-grade human glioma were compared with those obtained from normal mouse astrocytes and normal tissues. In cell analysis, the spectra at 950–1000, 1030, 1050–1100, 1120–1130, 1120–1200, 1200–1300, 1300–1350, and 1450 cm−1 were significantly higher in infiltrative glioma cells than in normal astrocytes. In brain tissue analysis, the spectra at 1030, 1050–1100, and 1200–1300 cm−1 were significantly higher in infiltrative glioma tissues than in normal brain tissues. These spectra reflect the structures of proteins, lipids, and DNA content. The sensitivity and specificity to predict glioma cells by distinguishing normal cells were 98.3% and 75.0%, respectively. Principal component analysis elucidated the significance of spectral difference between tumor tissues and normal tissues. It is possible to distinguish invasive tumors from normal tissues by using Raman spectroscopy.

  7. The protective effect of fermented Curcuma longa L. on memory dysfunction in oxidative stress-induced C6 gliomal cells, proinflammatory-activated BV2 microglial cells, and scopolamine-induced amnesia model in mice.

    Science.gov (United States)

    Eun, Cheong-Su; Lim, Jong-Soon; Lee, Jihye; Lee, Sam-Pin; Yang, Seun-Ah

    2017-07-17

    Curcuma longa L. is a well-known medicinal plant that has been used for its anti-cancer, neuroprotective, and hepatoprotective effects. However, the neuroprotective effect of fermented C. longa (FCL) has not been reported. Therefore, in this study, the effectiveness of FCL for the regulation of memory dysfunction was investigated in two brain cell lines (rat glioma C6 and murine microglia BV2) and scopolamine-treated mice. C. longa powder was fermented by 5% Lactobacillus plantarum K154 containing 2% (w/v) yeast extract at 30 °C for 72 h followed by sterilization at 121 °C for 15 min. The protective effects of fermented C. longa (FCL) on oxidative stress induced cell death were analyzed by MTT assay in C6 cells. The anti-inflammatory effects of FCL were investigated by measuring the production of nitric oxide (NO) and prostaglandin E2 (PGE2) as well as the expression levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated BV2 cells. The step-through passive avoidance test, Morris water maze test, acetylcholinesterase (AChE) activity, and expression of cAMP response element-binding protein (CREB) and brain-derived neurotropic factor (BDNF) were employed to determine the effects of FCL on scopolamine-induced memory deficit in mice. The contents of curcuminoids were analyzed through LC/MS. Pretreatment with FCL effectively prevented the cell death induced by oxidative stress in C6 cells. Moreover, FCL inhibited the production NO and PGE2 via the inhibition of iNOS and COX-2 expression in BV2 cells. FCL significantly attenuated scopolamine-induced memory impairment in mice and prevented scopolamine-induced AChE activity in the hippocampus. Additionally, FCL reversed the reduction of CREB and BDNF expression. The curcuminoids content in FCL was 1.44%. FCL pretreatment could alleviate scopolamine-induced memory impairment in mice, as well as oxidative stress and inflammation in C6 and BV2 cells, respectively. Thus, FCL might be a

  8. Toxic effects of apomorphine on rat cultured neurons and glial C6 cells, and protection with antioxidants.

    Science.gov (United States)

    dos Santos El-Bachá, R; Daval, J; Koziel, V; Netter, P; Minn, A

    2001-01-01

    Many catechol derivatives are currently used as drugs, even if they produce reactive oxygen species that may cause tissue damage. Among them, apomorphine, a potent dopamine agonist, displays efficient anti-parkinsonian properties, but the consequences of its oxidant and toxic properties have been poorly investigated on in vitro models. In the present work, we investigated apomorphine cytotoxicity by incubating cultures of rat glioma C6 cells and primary cultures of neurons with different concentrations of the drug. Apomorphine-promoted cell death was proportional to its concentration and was time-dependent. The ED(50) of apomorphine on C6 cell death after 48 hr was about 200 microM. The cytotoxic effects induced by apomorphine were correlated to its autoxidation, which leads to the formation of reactive oxygen species, semiquinones, quinones, and a melanin-like pigment. C6 cells that underwent treatment with 400 microM apomorphine for 6 hr displayed features of necrosis, including loss of membrane integrity, degeneration of mitochondria, and DNA fragmentation. Thiols, such as cysteine, N-acetyl-L-cysteine, and glutathione, significantly protected cultured neurons and C6 cells against apomorphine-induced cytotoxicity. Thiols also inhibited apomorphine autoxidation. These data strongly suggest that apomorphine cytotoxicity towards neurons and C6 cells results from an intracellular oxidative stress.

  9. A novel zebrafish xenotransplantation model for study of glioma stem cell invasion.

    Directory of Open Access Journals (Sweden)

    Xiao-Jun Yang

    Full Text Available Invasion and metastasis of solid tumors are the major causes of death in cancer patients. Cancer stem cells (CSCs constitute a small fraction of tumor cell population, but play a critical role in tumor invasion and metastasis. The xenograft of tumor cells in immunodeficient mice is one of commonly used in vivo models to study the invasion and metastasis of cancer cells. However, this model is time-consuming and labor intensive. Zebrafish (Danio rerio and their transparent embryos are emerging as a promising xenograft tumor model system for studies of tumor invasion. In this study, we established a tumor invasion model by using zebrafish embryo xenografted with human glioblastoma cell line U87 and its derived cancer stem cells (CSCs. We found that CSCs-enriched from U87 cells spreaded via the vessels within zebrafish embryos and such cells displayed an extremely high level of invasiveness which was associated with the up-regulated MMP-9 by CSCs. The invasion of glioma CSCs (GSCs in zebrafish embryos was markedly inhibited by an MMP-9 inhibitor. Thus, our zebrafish embryo model is considered a cost-effective approach tostudies of the mechanisms underlying the invasion of CSCs and suitable for high-throughput screening of novel anti-tumor invasion/metastasis agents.

  10. Segmentation of solid subregion of high grade gliomas in MRI images based on active contour model (ACM)

    Science.gov (United States)

    Seow, P.; Win, M. T.; Wong, J. H. D.; Abdullah, N. A.; Ramli, N.

    2016-03-01

    Gliomas are tumours arising from the interstitial tissue of the brain which are heterogeneous, infiltrative and possess ill-defined borders. Tumour subregions (e.g. solid enhancing part, edema and necrosis) are often used for tumour characterisation. Tumour demarcation into substructures facilitates glioma staging and provides essential information. Manual segmentation had several drawbacks that include laborious, time consuming, subjected to intra and inter-rater variability and hindered by diversity in the appearance of tumour tissues. In this work, active contour model (ACM) was used to segment the solid enhancing subregion of the tumour. 2D brain image acquisition data using 3T MRI fast spoiled gradient echo sequence in post gadolinium of four histologically proven high-grade glioma patients were obtained. Preprocessing of the images which includes subtraction and skull stripping were performed and then followed by ACM segmentation. The results of the automatic segmentation method were compared against the manual delineation of the tumour by a trainee radiologist. Both results were further validated by an experienced neuroradiologist and a brief quantitative evaluations (pixel area and difference ratio) were performed. Preliminary results of the clinical data showed the potential of ACM model in the application of fast and large scale tumour segmentation in medical imaging.

  11. Molecular Profiling of Gliomas

    NARCIS (Netherlands)

    A.M. Gravendeel (Lonneke)

    2012-01-01

    textabstractGliomas are the most common type of primary brain tumors in adults with an incidence rate of 5.27 per 100.000 patients every year 1-2. In 1926, Bailey and Cushing suggested a classification model based on distinct histological morphologies 3, which forms the basis of the currently used W

  12. D-amino acid oxidase gene therapy sensitizes glioma cells to the antiglycolytic effect of 3-bromopyruvate.

    Science.gov (United States)

    El Sayed, S M; Abou El-Magd, R M; Shishido, Y; Chung, S P; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

    2012-01-01

    Glioma tumors are refractory to conventional treatment. Glioblastoma multiforme is the most aggressive type of primary brain tumors in humans. In this study, we introduce oxidative stress-energy depletion (OSED) therapy as a new suggested treatment for glioblastoma. OSED utilizes D-amino acid oxidase (DAO), which is a promising therapeutic protein that induces oxidative stress and apoptosis through generating hydrogen peroxide (H2O2). OSED combines DAO with 3-bromopyruvate (3BP), a hexokinase II (HK II) inhibitor that interferes with Warburg effect, a metabolic alteration of most tumor cells that is characterized by enhanced aerobic glycolysis. Our data revealed that 3BP induced depletion of energetic capabilities of glioma cells. 3BP induced H2O2 production as a novel mechanism of its action. C6 glioma transfected with DAO and treated with D-serine together with 3BP-sensitized glioma cells to 3BP and decreased markedly proliferation, clonogenic power and viability in a three-dimensional tumor model with lesser effect on normal astrocytes. DAO gene therapy using atelocollagen as an in vivo transfection agent proved effective in a glioma tumor model in Sprague-Dawley (SD) rats, especially after combination with 3BP. OSED treatment was safe and tolerable in SD rats. OSED therapy may be a promising therapeutic modality for glioma.

  13. ANTITUMOR EFFECT OF SARCNU IN A 06-METHYLGUANINE-DNA METHYLTRANSFERASE POSITIVE HUMAN GLIOMA XENOGRAFT MODEL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To assess whether novel analogue of nitrosoureas, 2-chloroethyl-3-sarcosinamide-1-nitrosourea (SarCNU), has antitumor effect to 06-methylguanine-DNA methyltransferase (MGMT) positive tumors in vivo. Methods: MGMT positive human glioma cell line SF-767 xenografts in nude mice were treated with SarCNU. The antitumor efficacy of SarCNU was compared with the results of 1, 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) treatment with or without 06-benzylguanine (06-BG) preadministration. Results: Since the SF-767 is MGMT strongly positive, BCNU treatment alone did not result in a satisfactory anticancer effect. As expected, 06-BG by depleting MGMT activity, significantly enhanced BCNU antitumor efficacy (p<0.001). More interestingly, SarCNU treatment alone had a better antitumor effect than 06-BG plus BCNU treatment (F=51.7, p=0.00036). Conclusion: Since SarCNU enters cells via extraneuronal monoamine transporter (EMT), the enhanced antitumor activity of SarCNU in this MGMT positive human tumor xenograft model may be due to the presence of EMT in SF-767.SarCNU may be used as an alternative treatment for MGMT positive tumors, specifically for tumors expressing EMT.

  14. Conceptual Design of Object Oriented Program (OOP) for Pilot Code of Two-Fluid, Three-field Model with C++ 6.0

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Bub Dong; Lee, Young Jin [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    Engineering software for design purpose in nuclear industries have been developed since early 1970s, and well established in 1980s. The most popular and common language for the software development has been FORTRAN series, until the more sophisticated GUI and software coupling is needed. The advanced computer language, such as C++, C has been developed to help the programming for the easy GUI need and reuse of well developed routines, with adopting the objective oriented program. A recent trend of programming becomes objective-oriented since the results are often more intuitive and easier to maintain than procedure program. The main motivation of this work is to capture objective oriented concepts for conventional safety analysis programs which consist of many functions and procedure oriented structures. In this work, the new objective programming with C++ 6.0 language has been tried for the PILOT code written in FORTRAN language, and conceptual OOP design of the system safety analysis code has been done.

  15. The flavonoid apigenin from Croton betulaster Mull inhibits proliferation, induces differentiation and regulates the inflammatory profile of glioma cells.

    Science.gov (United States)

    Coelho, Paulo L C; Oliveira, Mona N; da Silva, Alessandra B; Pitanga, Bruno P S; Silva, Victor D A; Faria, Giselle P; Sampaio, Geraldo P; Costa, Maria de Fatima D; Braga-de-Souza, Suzana; Costa, Silvia L

    2016-11-01

    This study aimed to investigate the antitumor and immunomodulatory properties of the flavonoid apigenin (5,7,4'-trihydroxyflavone), which was extracted from Croton betulaster Mull, in glioma cell culture using the high-proliferative rat C6 glioma cell line as a model. Apigenin was found to have the ability to reduce the viability and proliferation of C6 cells in a time-dependent and dose-dependent manner, with an IC50 of 22.8 µmol/l, 40 times lower than that of temozolomide (1000 µmol/l), after 72 h of apigenin treatment. Even after C6 cells were treated with apigenin for 48 h, high proportions of C6 cells entered apoptosis (39.56%) and autophagy (22%) as shown by flow cytometry using annexin V/propidium iodide and acridine orange staining, respectively. In addition, the flavonoid apigenin induced cell accumulation in the G0/G1 phase of the cell cycle and inhibited glioma cell migration efficiently. Moreover, apigenin induced astroglial differentiation and morphological changes in C6 cells, characterized by increased expression of glial fibrillary acidic protein and decreased expression of nestin protein, a typical marker of neuronal precursors. The immunomodulating effects of apigenin were also characterized by a change in the inflammatory profile as evidenced by a significant decrease in interleukin-10 and tumor necrosis factor production and increased nitric oxide levels. Because apigenin can induce differentiation, apoptosis, and autophagy, can alter the profile of cytokines involved in regulating the immune response, and can reduce the survival, growth, proliferation, and migration of C6 cells, this flavonoid may be considered a potential antitumor drug for the adjuvant treatment of malignant gliomas.

  16. Therapeutic vaccination against malignant gliomas based on allorecognition and syngeneic tumour antigens: proof of principle in two strains of rat

    NARCIS (Netherlands)

    Stathopoulos, A.; Samuelson, C.; Milbouw, G.; Hermanne, J.P.; Schijns, V.E.J.C.; Chen, T.C.

    2008-01-01

    In the present study we investigated whether allogeneic glioma cells can be utilized to evoke prophylactic or therapeutic immune-mediated elimination of syngeneic glioma in two rat strains. Fisher 344 and Sprague–Dawley (SD) rats were injected with two syngeneic glioma cell lines, 9L and C6, respect

  17. Sensitivity of MRI tumor biomarkers to VEGFR inhibitor therapy in an orthotopic mouse glioma model.

    Directory of Open Access Journals (Sweden)

    Christian T Farrar

    Full Text Available MRI biomarkers of tumor edema, vascular permeability, blood volume, and average vessel caliber are increasingly being employed to assess the efficacy of tumor therapies. However, the dependence of these biomarkers on a number of physiological factors can compromise their sensitivity and complicate the assessment of therapeutic efficacy. Here we examine the response of these MRI tumor biomarkers to cediranib, a potent vascular endothelial growth factor receptor (VEGFR inhibitor, in an orthotopic mouse glioma model. A significant increase in the tumor volume and relative vessel caliber index (rVCI and a slight decrease in the water apparent diffusion coefficient (ADC were observed for both control and cediranib treated animals. This contrasts with a clinical study that observed a significant decrease in tumor rVCI, ADC and volume with cediranib therapy. While the lack of a difference between control and cediranib treated animals in these biomarker responses might suggest that cediranib has no therapeutic benefit, cediranib treated mice had a significantly increased survival. The increased survival benefit of cediranib treated animals is consistent with the significant decrease observed for cediranib treated animals in the relative cerebral blood volume (rCBV, relative microvascular blood volume (rMBV, transverse relaxation time (T2, blood vessel permeability (K(trans, and extravascular-extracellular space (ν(e. The differential response of pre-clinical and clinical tumors to cediranib therapy, along with the lack of a positive response for some biomarkers, indicates the importance of evaluating the whole spectrum of different tumor biomarkers to properly assess the therapeutic response and identify and interpret the therapy-induced changes in the tumor physiology.

  18. Neural progenitor and hemopoietic stem cells inhibit the growth of low-differentiated glioma.

    Science.gov (United States)

    Baklaushev, V P; Grinenko, N F; Savchenko, E A; Bykovskaya, S N; Yusubalieva, G M; Viktorov, I V; Bryukhovetskii, A S; Bryukhovetskii, I S; Chekhonin, V P

    2012-02-01

    The effects of neural progenitor and hemopoietic stem cells on C6 glioma cells were studied in in vivo and in vitro experiments. Considerable inhibition of proliferation during co-culturing of glioma cells with neural progenitor cells was revealed by quantitative MTT test and bromodeoxyuridine incorporation test. Labeled neural progenitor and hemopoietic stem cells implanted into the focus of experimental cerebral glioma C6 survive in the brain of experimental animals for at least 7 days, migrate with glioma cells, and accumulate in the peritumoral space. Under these conditions, neural progenitor cells differentiate with the formation of long processes. Morphometric analysis of glioma cells showed that implantation of neural progenitor and hemopoietic stem cells is accompanied by considerable inhibition of the growth of experimental glioma C6 in comparison with the control. The mechanisms of tumor-suppressive effects of neural and hemopoietic stem cells require further investigation.

  19. Metronomic Doses of Temozolomide Enhance the Efficacy of Carbon Nanotube CpG Immunotherapy in an Invasive Glioma Model

    Science.gov (United States)

    Guo, Qin; Zhang, Ian; Gao, Hang; Yanyan, Song; Chen, Xuebo; Weng, Yiming; Da Fonseca, Anna; Shah, Sunny; Manuel, Edwin R.; Zhang, Leying; Vonderfecht, Steven L.; Alizadeh, Darya; Berlin, Jacob M.; Badie, Behnam

    2016-01-01

    Even when treated with aggressive current therapies, most patients with glioblastoma survive less than two years. Rapid tumor growth, an invasive nature, and the blood-brain barrier, which limits the penetration of large molecules into the brain, all contribute to the poor tumor response associated with conventional therapies. Immunotherapy has emerged as a therapeutic approach that may overcome these challenges. We recently reported that single-walled carbon nanotubes (SWCNTs) can be used to dramatically increase the immunotherapeutic efficacy of CpG oligonucleotides in a mouse model of glioma. Following implantation in the mouse brain, the tumor cell line used in these previous studies (GL261) tends to form a spherical tumor with limited invasion into healthy brain. In order to evaluate SWCNT/CpG therapy under more clinically-relevant conditions, here we report the treatment of a more invasive mouse glioma model (K-Luc) that better recapitulates human disease. In addition, a CpG sequence previously tested in humans was used to formulate the SWCNT/CpG which was combined with temozolomide, the standard of care chemotherapy for glioblastoma patients. We found that, following two intracranial administrations, SWCNT/CpG is well-tolerated and improves the survival of mice bearing invasive gliomas. Interestingly, the efficacy of SWCNT/CpG was enhanced when combined with temozolomide. This enhanced anti-tumor efficacy was correlated to an increase of tumor-specific cytotoxic activity in splenocytes. These results reinforce the emerging understanding that immunotherapy can be enhanced by combining it with chemotherapy and support the continued development of SWCNT/CpG. PMID:26829221

  20. Metronomic Doses of Temozolomide Enhance the Efficacy of Carbon Nanotube CpG Immunotherapy in an Invasive Glioma Model.

    Directory of Open Access Journals (Sweden)

    Mao Ouyang

    Full Text Available Even when treated with aggressive current therapies, most patients with glioblastoma survive less than two years. Rapid tumor growth, an invasive nature, and the blood-brain barrier, which limits the penetration of large molecules into the brain, all contribute to the poor tumor response associated with conventional therapies. Immunotherapy has emerged as a therapeutic approach that may overcome these challenges. We recently reported that single-walled carbon nanotubes (SWCNTs can be used to dramatically increase the immunotherapeutic efficacy of CpG oligonucleotides in a mouse model of glioma. Following implantation in the mouse brain, the tumor cell line used in these previous studies (GL261 tends to form a spherical tumor with limited invasion into healthy brain. In order to evaluate SWCNT/CpG therapy under more clinically-relevant conditions, here we report the treatment of a more invasive mouse glioma model (K-Luc that better recapitulates human disease. In addition, a CpG sequence previously tested in humans was used to formulate the SWCNT/CpG which was combined with temozolomide, the standard of care chemotherapy for glioblastoma patients. We found that, following two intracranial administrations, SWCNT/CpG is well-tolerated and improves the survival of mice bearing invasive gliomas. Interestingly, the efficacy of SWCNT/CpG was enhanced when combined with temozolomide. This enhanced anti-tumor efficacy was correlated to an increase of tumor-specific cytotoxic activity in splenocytes. These results reinforce the emerging understanding that immunotherapy can be enhanced by combining it with chemotherapy and support the continued development of SWCNT/CpG.

  1. Characterizing C6+P2-graphic Sequences

    Institute of Scientific and Technical Information of China (English)

    HU Li-li

    2014-01-01

    For a given graph H, a graphic sequence π = (d1, d2, · · · , dn) is said to be potentially H-graphic if π has a realization containing H as a subgraph. In this paper, we characterize the potentially C6 +P2-graphic sequences where C6 +P2 denotes the graph obtained from C6 by adding two adjacent edges to the three pairwise nonadjacent vertices of C6. Moreover, we use the characterization to determine the value ofσ(C6+P2, n).

  2. Dynamics of Circulating γδ T Cell Activity in an Immunocompetent Mouse Model of High-Grade Glioma.

    Directory of Open Access Journals (Sweden)

    Benjamin H Beck

    Full Text Available Human γδ T cells are potent effectors against glioma cell lines in vitro and in human/mouse xenograft models of glioblastoma, however, this effect has not been investigated in an immunocompetent mouse model. In this report, we established GL261 intracranial gliomas in syngeneic WT C57BL/6 mice and measured circulating γδ T cell count, phenotype, Vγ/Vδ repertoire, tumor histopathology, NKG2D ligands expression, and T cell invasion at day 10-12 post-injection and at end stage. Circulating γδ T cells transiently increased and upregulated Annexin V expression at post-tumor day 10-12 followed by a dramatic decline in γδ T cell count at end stage. T cell receptor repertoire showed no changes in Vγ1, Vγ4, Vγ7 or Vδ1 subsets from controls at post-tumor day 10-12 or at end stage except for an end-stage increase in the Vδ4 population. Approximately 12% of γδ T cells produced IFN-γ. IL-17 and IL-4 producing γδ T cells were not detected. Tumor progression was the same in TCRδ-/- C57BL/6 mice as that observed in WT mice, suggesting that γδ T cells exerted neither a regulatory nor a sustainable cytotoxic effect on the tumor. WT mice that received an intracranial injection of γδ T cells 15m following tumor placement showed evidence of local tumor growth inhibition but this was insufficient to confer a survival advantage over untreated controls. Taken together, our findings suggest that an early nonspecific proliferation of γδ T cells followed by their depletion occurs in mice implanted with syngeneic GL261 gliomas. The mechanism by which γδ T cell expansion occurs remains a subject for further investigation of the mechanisms responsible for this immune response in the setting of high-grade glioma.

  3. Focused ultrasound enhanced molecular imaging and gene therapy for multifusion reporter gene in glioma-bearing rat model.

    Science.gov (United States)

    Yang, Feng-Yi; Chang, Wen-Yuan; Lin, Wei-Ting; Hwang, Jeng-Jong; Chien, Yi-Chun; Wang, Hsin-Ell; Tsai, Min-Lan

    2015-11-03

    The ability to monitor the responses of and inhibit the growth of brain tumors during gene therapy has been severely limited due to the blood-brain barrier (BBB). A previous study has demonstrated the feasibility of noninvasive in vivo imaging with 123I-2'-fluoro-2'-deoxy-5-iodo-1-β-D-arabinofuranosyluracil (123I-FIAU) for monitoring herpes simplex virus type 1 thymidine kinase (HSV1-tk) cancer gene expression in an experimental animal model. Here, we tested the enhancement of SPECT with 123I-FIAU and ganciclovir (GCV) treatment in brain tumors after BBB disruption induced by focused ultrasound (FUS) in the presence of microbubbles. We established an orthotopic F98 glioma-bearing rat model with trifusion reporter genes. The results of this study showed that the rat model of HSV1-tk-expressing glioma cells could be successfully detected by SPECT imaging after FUS-induced BBB disruption on day 10 after implantation. Compared to the control group, animals receiving the GCV with or without sonication exhibited a significant antitumor activity (P therapy in brain diseases.

  4. Modeling tumor-associated edema in gliomas during anti-angiogenic therapy and its impact on imageable tumor

    Directory of Open Access Journals (Sweden)

    Andrea eHawkins-Daarud

    2013-04-01

    Full Text Available Glioblastoma, the most aggressive form of primary brain tumor is predominantly assessed with gadolinium-enhanced T1-weighted (T1Gd and T2-weighted magnetic resonance imaging (MRI. Pixel intensity enhancement on the T1Gd image is understood to correspond to the gadolinium contrast agent leaking from the tumor-induced neovasculature, while hyperintensity on the T2/FLAIR images corresponds with edema and infiltrated tumor cells. None of these modalities directly show tumor cells; rather, they capture abnormalities in the microenvironment caused by the presence of tumor cells. Thus, assessing disease response after treatments impacting the microenvironment remains challenging through the obscuring lens of MR imaging. Anti-angiogenic therapies have been used in the treatment of gliomas with spurious results ranging from no apparent response to significant imaging improvement with the potential for extremely diffuse patterns of tumor recurrence on imaging and autopsy. Anti-angiogenic treatment normalizes the vasculature, effectively decreasing vessel permeability and thus reducing tumor-induced edema, drastically altering T2-weighted MRI. We extend a previously developed mathematical model of glioma growth to explicitly incorporate edema formation allowing us to directly characterize and potentially predict the effects of anti-angiogenics on imageable tumor growth. A comparison of simulated glioma growth and imaging enhancement with and without bevacizumab supports the current understanding that anti-angiogenic treatment can serve as a surrogate for steroids and the clinically-driven hypothesis that anti-angiogenic treatment may not have any significant effect on the growth dynamics of the overall tumor-cell populations. However, the simulations do illustrate a potentially large impact on the level of edematous extracellular fluid, and thus on what would be imageable on T2/FLAIR MR for tumors with lower proliferation rates.

  5. Experimental Study on Treatment of Glioma by Embyonic Neural Stem Cell Transplnation in Rats

    Institute of Scientific and Technical Information of China (English)

    LUO Jie; ZHANG Li; TU Hanjun; HU Juntao; LI Xinjian; LI Dongsheng; LEI Ting

    2007-01-01

    The neural stem cells in Wistar rats were cultured in vitro, purified, and transplanted into C6 glioma model in order to observe their biological characters and provide a basic foundation for treatment of neurological diseases by neural stem cell transplantation. The cells at hippocampal area from gestation 15-day rats were cultured in vitro, and frozen and preserved in liquid nitrogen. C6 tu-mor-bearing models (n=25) and neural stem cells transplantation models (n=35) were established.When the tumor grew to 3 to 4 weeks,5 rats in each group were randomly selected for MRI examina-tion. At different intervals, the rats were perfused and sampled for HE staining, GFAP and BrdU im-munohistochemical staining. The results showed that after resuscitation of neural stem cells at 1-4 passages, the cell viability was 40%-63% with the difference being not significant. The cells could proliferate, passage, and most cells transplanted into glioma model survived. The mean survival time in neural stem cell transplantation group and control was 4.28 and 3.88 weeks respectively, and the average tumor size in the former was smaller than in the latter. It was concluded that embryonic neu- ral stem cells in rats could proliferate and differentiate, and after resuscitation the biological charac- teristic and viability of the cells were not influenced. Neural stem cells had inhibitory effects on the growth of glioma cells and could prolong the survival of rat model.

  6. Incubation and application of transgenic green fluorescent nude mice in visualization studies on glioma tissue remodeling

    Institute of Scientific and Technical Information of China (English)

    DONG Jun; LAN Qing; HUANG Qiang; DAI Xing-liang; LU Zhao-hui; FEI Xi-feng; CHEN Hua; ZHANG Quan-bin; ZHAO Yao-dong; WANG Zhi-min; WANG Ai-dong

    2012-01-01

    Background The primary reasons for local recurrence and therapeutic failure in the treatment of malignant gliomas are the invasion and interactions of tumor cells with surrounding normal brain cells.However,these tumor cells are hard to be visualized directly in histopathological preparations,or in experimental glioma models.Therefore,we developed an experimental human dual-color in vivo glioma model,which made tracking solitary invasive glioma cells possible,for the purpose of visualizing the interactions between red fluorescence labeled human glioma cells and host brain cells.This may offer references for further studying the roles of tumor microenvironment during glioma tissue remodeling.Methods Transgenic female C57BL/6 mice expressing enhanced green fluorescent protein (EGFP) were crossed with male Balb/c nude mice.Then sib mating was allowed to occur continuously in order to establish an inbred nude mice strain with 50% of their offspring that are EGFP positive.Human glioma cell lines U87-MG and SU3 were transfected with red fluorescent protein (RFP) gene,and a rat C6 glioma cell line was stained directly with CM-Dil,to establish three glioma cell lines emitting red fluorescence (SU3-RFP,U87-RFP,and C6-CM-Dil).Red fluorescence tumor cells were inoculated via intra-cerebral injection into caudate nucleus of the EGFP nude mice.Tumor-bearing mice were sacrificed when their clinical symptoms appeared,and the whole brain was harvested and snap frozen for further analysis.Confocal laser scanning microscopy was performed to monitor the mutual interactions between tumor cells and host brain cells.Results Almost all the essential tissues of the established EGFP athymic Balb/c nude mice,except hair and erythrocytes,fluoresced green under excitation using a blue light-emitting flashlight with a central peak of 470 nm,approximately 50% of the offsprings were nu/nu EGFP+.SU3-RFP,U87-RFP,and C6-CM-Dil almost 100% expressed red fluorescence under the fluorescence

  7. Molecular and phenotypic characterisation of paediatric glioma cell lines as models for preclinical drug development

    DEFF Research Database (Denmark)

    Bax, Dorine A; Little, Suzanne E; Gaspar, Nathalie;

    2009-01-01

    in comparison to routinely used adult lines. PRINCIPAL FINDINGS: All lines proliferate as adherent monolayers and express glial markers. Copy number profiling revealed complex genomes including amplification and deletions of genes known to be pivotal in core glioblastoma signalling pathways. Expression...... profiling identified 93 differentially expressed genes which were able to distinguish between the adult and paediatric high grade cell lines, including a number of kinases and co-ordinated sets of genes associated with DNA integrity and the immune response. SIGNIFICANCE: These data demonstrate that glioma...... cell lines derived from paediatric patients show key molecular differences to those from adults, some of which are well known, whilst others may provide novel targets for evaluation in primary tumours. We thus provide the rationale and demonstrate the practicability of using paediatric glioma cell...

  8. Stochastic modelling of slow-progressing tumors: Analysis and applications to the cell interplay and control of low grade gliomas

    Science.gov (United States)

    Rodríguez, Clara Rojas; Fernández Calvo, Gabriel; Ramis-Conde, Ignacio; Belmonte-Beitia, Juan

    2017-08-01

    Tumor-normal cell interplay defines the course of a neoplastic malignancy. The outcome of this dual relation is the ultimate prevailing of one of the cells and the death or retreat of the other. In this paper we study the mathematical principles that underlay one important scenario: that of slow-progressing cancers. For this, we develop, within a stochastic framework, a mathematical model to account for tumor-normal cell interaction in such a clinically relevant situation and derive a number of deterministic approximations from the stochastic model. We consider in detail the existence and uniqueness of the solutions of the deterministic model and study the stability analysis. We then focus our model to the specific case of low grade gliomas, where we introduce an optimal control problem for different objective functionals under the administration of chemotherapy. We derive the conditions for which singular and bang-bang control exist and calculate the optimal control and states.

  9. A Spectroscopic Survey of Electronic Transitions of C$_6$H, $^{13}$C$_6$H, and C$_6$D

    CERN Document Server

    Bacalla, Xavier; Linnartz, Harold; Ubachs, Wim; Zhao, Dongfeng

    2016-01-01

    Electronic spectra of C$_6$H are measured in the $18\\,950-21\\,100$ cm$^{-1}$ domain using cavity ring-down spectroscopy of a supersonically expanding hydrocarbon plasma. In total, 19 (sub)bands of C$_6$H are presented, all probing the vibrational manifold of the B$^2\\Pi$ electronically excited state. The assignments are guided by electronic spectra available from matrix isolation work, isotopic substitution experiments (yielding also spectra for $^{13}$C$_6$H and C$_6$D), predictions from ab initio calculations as well as rotational fitting and vibrational contour simulations using the available ground state parameters as obtained from microwave experiments. Besides the $0_0^0$ origin band, three non-degenerate stretching vibrations along the linear backbone of the C$_6$H molecule are assigned: the $\

  10. Establishment of human iPSC-based models for the study and targeting of glioma initiating cells

    Science.gov (United States)

    Sancho-Martinez, Ignacio; Nivet, Emmanuel; Xia, Yun; Hishida, Tomoaki; Aguirre, Aitor; Ocampo, Alejandro; Ma, Li; Morey, Robert; Krause, Marie N.; Zembrzycki, Andreas; Ansorge, Olaf; Vazquez-Ferrer, Eric; Dubova, Ilir; Reddy, Pradeep; Lam, David; Hishida, Yuriko; Wu, Min-Zu; Esteban, Concepcion Rodriguez; O'Leary, Dennis; Wahl, Geoffrey M.; Verma, Inder M.; Laurent, Louise C.; Izpisua Belmonte, Juan Carlos

    2016-01-01

    Glioma tumour-initiating cells (GTICs) can originate upon the transformation of neural progenitor cells (NPCs). Studies on GTICs have focused on primary tumours from which GTICs could be isolated and the use of human embryonic material. Recently, the somatic genomic landscape of human gliomas has been reported. RTK (receptor tyrosine kinase) and p53 signalling were found dysregulated in ∼90% and 86% of all primary tumours analysed, respectively. Here we report on the use of human-induced pluripotent stem cells (hiPSCs) for modelling gliomagenesis. Dysregulation of RTK and p53 signalling in hiPSC-derived NPCs (iNPCs) recapitulates GTIC properties in vitro. In vivo transplantation of transformed iNPCs leads to highly aggressive tumours containing undifferentiated stem cells and their differentiated derivatives. Metabolic modulation compromises GTIC viability. Last, screening of 101 anti-cancer compounds identifies three molecules specifically targeting transformed iNPCs and primary GTICs. Together, our results highlight the potential of hiPSCs for studying human tumourigenesis. PMID:26899176

  11. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1.

    Science.gov (United States)

    Josupeit, Rafael; Bender, Sebastian; Kern, Sonja; Leuchs, Barbara; Hielscher, Thomas; Herold-Mende, Christel; Schlehofer, Jörg R; Dinsart, Christiane; Witt, Olaf; Rommelaere, Jean; Lacroix, Jeannine

    2016-05-19

    Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG). A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV) in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6), including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50) doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM) "stem-like" cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance.

  12. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1

    Directory of Open Access Journals (Sweden)

    Rafael Josupeit

    2016-05-01

    Full Text Available Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG. A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6, including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50 doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM “stem-like” cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance.

  13. EXPERIMENTAL STUDY ON THE GENE THERAPY OF MALIGNANT GLIOMA WITH ANTISENSE VEGF RNA

    Institute of Scientific and Technical Information of China (English)

    浦佩玉; 王建桢; 黄强; 张敬; 张云亭

    2003-01-01

    Objective: To study the effect of antisense VEGF RNA on rat C6 gliomas in vivo and find out the feasibility of antiangiogenesis therapy with antisense VEGF RNA for malignant gliomas. Methods: Parental rat C6 glioma cells and C6 cells transfected with antisense VEGF cDNA were implanted intracerebrally and subcutaneously into SD rats as control and transfected group. Rats bearing cerebral and subcutaneous C6 gliomas were treated with antisense VEGF cDNA as treated group and sense VEGF cDNA and empty vector as control of treated group. The general manifestation, survival time, MRI and histopathological changes of all rats were observed. The volume of subcutaneously implanted tumors was determined regularly. In situ hybridization and immunohistochemical staining were used for detection of VEGF gene expression of gliomas while PCNA immunostaining and TUNEL method for examination of proliferation activity and apoptosis of gliomas, respectively. Results: The survival of the rats in transfected and treated group was prolonged. There were two rats surviving over 90 d in the treated group and their tumors disappeared. The VEGF gene expression, the number of microvessels and the proliferation activity were decreased and a large amount of apoptotic cells could be found in cerebral and subcutaneous gliomas in treated and transfected groups. Conclusion: VEGF is one of the candidate genes for gene therapy of malignant gliomas. Antisense VEGF RNA combined with other therapies should be studied further for enhancing the therapeutic effect of malignant gliomas.

  14. Significance of the expression of green fluorescent protein on detection of glioma invasion in vivo

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To investigate the invasion and metastasis of gliomain vivo by xenotransplanted tumor established by implanting C6 glioma cells transfected with green fluorescent protein (GFP) gene in vitro into the brain of SD rats. Methods: C6 cells were transfected with a plasmid vector (pEGEP-N3) containing the GFP gene. Stable GFP-expressing clones were isolated and performed examination by flow cytometry and electron microscope. GFP-expressing cells were stereotactically injected into the brain parenchyma of SD rats to establish xenotransplanted tumor. Four weeks later rats were killed and continuous brain sections respectively were examined by HE staining, immunohistochemistry method and fluorescence microscopy for detection of tumor cell invasion. Xenotransplanted tumor was primarily cultured to determine the storage of exotic GFP gene in vivo. Results: There were not obvious changes in cell cycle and ultrastructure for the cells transfected with GFP gene. C6 cells transfected with GFP gene maintained stable high-level GFP expression in the central nervous system during their growth in vivo. GFP fluorescence clearly demarcated the primary tumor margin and readily allowed for the detection of distant invasion on the single-cell level, which was evidently superior to HE and immunohistochemistry staining. There was not GFP gene loss of transfected cells in vivo. Conclusions: It is suggested that C6 cells transfected with GFP gene can be visualized by fluorescent microscopy after intracranial implantation. This model is an excellent experimental animal model in research on invasion of glioma.

  15. Bone marrow-derived mesenchymal stem cells to glioma directional migration and DAPI markers%骨髓间充质干细胞向脑胶质瘤定向迁移及其DAPI标记的研究

    Institute of Scientific and Technical Information of China (English)

    程鹏; 胡宜; 刘云会

    2012-01-01

    OBJECTIVE: To investigate the migrating potential of bone marrow-derived mesenchymal stem cells (BMSCs) towards C6 glioma and the application value of DAPI in the tracking and migration of BMSCs towards glioma in vivo. METHODS: BMSCs were isolated,cultured,passaged and purified in vitro by direct adhesion method. Using Tran-swell inserts technique,in vitro model was established and the migration of BMSCs towards C6 glioma was studied. The rat C6 glioma model was established by stereotactic procedure. After being marked with DAPI,BMSCs were injected into collateral internal carotid artery of rats bearing glioma to study their tropism for C6 glioma in vivo and evaluated the application of DAPI in this process, RESULTS: BMSCs were successive subcultured and purified by direct adhesion method. The results of in vitro migration assay showed that BMSCs could migrate through the polycarbonate filter towards C6 cells. The average number of migrating BMSCs was (32. 1 ± 10. 5)/HP. ( × 400) . The nucleus of BMSCs labeled by DA-PI presented blue fluorescence,and all of the cells were labeled by DAPL After being injected into internal carotid artery, BMSCs could survive in the brain of rats bearing glioma,and showed extensive tropism for C6 glioma and scattered around the blood vessels within the tumor. CONCLUSIONS:DAPI can be used for the tracking of BMSCs in vivo. BMSCs have the ability to penetrate blood tumor barrier and migrate towards C6 glioma,and infusion through internal carotid artery is an effective way for their transplantation.%目的:探讨骨髓间充质干细胞(BSMCs)向C6胶质瘤定向迁移的能力以及DAPI用于BMSCs向胶质瘤体内迁移示踪的价值.方法:直接贴壁法分离培养纯化BMSCs.利用Transwell小室建立体外迁移模型检测BMSCs向C6胶质瘤细胞定向迁移的能力.立体定向法建立大鼠C6胶质瘤模型,利用DAPI体外标记培养、纯化的BMSCs,经荷瘤侧颈内动脉灌注,观察BMSCs向C6胶质瘤组织的

  16. Apoptosis in glioma-bearing rats after neural stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    Hua Li; Zhenjun Chen; Shaopeng Zhou

    2013-01-01

    Abnormal activation of the Ras/Raf/Mek/Erk signaling cascade plays an important role in glioma. Inhibition of this aberrant activity could effectively hinder glioma cel proliferation and promote cell apoptosis. To investigate the mechanism of glioblastoma treatment by neural stem cel trans-plantation with respect to the Ras/Raf/Mek/Erk pathway, C6 glioma cel s were prepared in sus-pension and then infused into the rat brain to establish a glioblastoma model. Neural stem cells isolated from fetal rats were then injected into the brain of this glioblastoma model. Results showed that Raf-1, Erk and Bcl-2 protein expression significantly increased, while Caspase-3 protein expression decreased. After transplantation of neural stem cells, Raf-1, Erk and Bcl-2 protein expression significantly decreased, while Caspase-3 protein expression significantly in-creased. Our findings indicate that transplantation of neural stem cel s may promote apoptosis of glioma cells by inhibiting Ras/Raf/Mek/Erk signaling, and thus may represent a novel treatment approach for glioblastoma.

  17. The Ketogenic Diet Alters the Hypoxic Response and Affects Expression of Proteins Associated with Angiogenesis, Invasive Potential and Vascular Permeability in a Mouse Glioma Model.

    Directory of Open Access Journals (Sweden)

    Eric C Woolf

    Full Text Available The successful treatment of malignant gliomas remains a challenge despite the current standard of care, which consists of surgery, radiation and temozolomide. Advances in the survival of brain cancer patients require the design of new therapeutic approaches that take advantage of common phenotypes such as the altered metabolism found in cancer cells. It has therefore been postulated that the high-fat, low-carbohydrate, adequate protein ketogenic diet (KD may be useful in the treatment of brain tumors. We have demonstrated that the KD enhances survival and potentiates standard therapy in a mouse model of malignant glioma, yet the mechanisms are not fully understood.To explore the effects of the KD on various aspects of tumor growth and progression, we used the immunocompetent, syngeneic GL261-Luc2 mouse model of malignant glioma.Tumors from animals maintained on KD showed reduced expression of the hypoxia marker carbonic anhydrase 9, hypoxia inducible factor 1-alpha, and decreased activation of nuclear factor kappa B. Additionally, tumors from animals maintained on KD had reduced tumor microvasculature and decreased expression of vascular endothelial growth factor receptor 2, matrix metalloproteinase-2 and vimentin. Peritumoral edema was significantly reduced in animals fed the KD and protein analyses showed altered expression of zona occludens-1 and aquaporin-4.The KD directly or indirectly alters the expression of several proteins involved in malignant progression and may be a useful tool for the treatment of gliomas.

  18. Resistance to oncolytic myxoma virus therapy in nf1(-/-/trp53(-/- syngeneic mouse glioma models is independent of anti-viral type-I interferon.

    Directory of Open Access Journals (Sweden)

    Franz J Zemp

    Full Text Available Despite promising preclinical studies, oncolytic viral therapy for malignant gliomas has resulted in variable, but underwhelming results in clinical evaluations. Of concern are the low levels of tumour infection and viral replication within the tumour. This discrepancy between the laboratory and the clinic could result from the disparity of xenograft versus syngeneic models in determining in vivo viral infection, replication and treatment efficacy. Here we describe a panel of primary mouse glioma lines derived from Nf1 (+/- Trp53 (+/- mice in the C57Bl/6J background for use in the preclinical testing of the oncolytic virus Myxoma (MYXV. These lines show a range of susceptibility to MYXV replication in vitro, but all succumb to viral-mediated cell death. Two of these lines orthotopically grafted produced aggressive gliomas. Intracranial injection of MYXV failed to result in sustained viral replication or treatment efficacy, with minimal tumour infection that was completely resolved by 7 days post-infection. We hypothesized that the stromal production of Type-I interferons (IFNα/β could explain the resistance seen in these models; however, we found that neither the cell lines in vitro nor the tumours in vivo produce any IFNα/β in response to MYXV infection. To confirm IFNα/β did not play a role in this resistance, we ablated the ability of tumours to respond to IFNα/β via IRF9 knockdown, and generated identical results. Our studies demonstrate that these syngeneic cell lines are relevant preclinical models for testing experimental glioma treatments, and show that IFNα/β is not responsible for the MYXV treatment resistance seen in syngeneic glioma models.

  19. Resistance to oncolytic myxoma virus therapy in nf1(-/-)/trp53(-/-) syngeneic mouse glioma models is independent of anti-viral type-I interferon.

    Science.gov (United States)

    Zemp, Franz J; McKenzie, Brienne A; Lun, Xueqing; Maxwell, Lori; Reilly, Karlyne M; McFadden, Grant; Yong, V Wee; Forsyth, Peter A

    2013-01-01

    Despite promising preclinical studies, oncolytic viral therapy for malignant gliomas has resulted in variable, but underwhelming results in clinical evaluations. Of concern are the low levels of tumour infection and viral replication within the tumour. This discrepancy between the laboratory and the clinic could result from the disparity of xenograft versus syngeneic models in determining in vivo viral infection, replication and treatment efficacy. Here we describe a panel of primary mouse glioma lines derived from Nf1 (+/-) Trp53 (+/-) mice in the C57Bl/6J background for use in the preclinical testing of the oncolytic virus Myxoma (MYXV). These lines show a range of susceptibility to MYXV replication in vitro, but all succumb to viral-mediated cell death. Two of these lines orthotopically grafted produced aggressive gliomas. Intracranial injection of MYXV failed to result in sustained viral replication or treatment efficacy, with minimal tumour infection that was completely resolved by 7 days post-infection. We hypothesized that the stromal production of Type-I interferons (IFNα/β) could explain the resistance seen in these models; however, we found that neither the cell lines in vitro nor the tumours in vivo produce any IFNα/β in response to MYXV infection. To confirm IFNα/β did not play a role in this resistance, we ablated the ability of tumours to respond to IFNα/β via IRF9 knockdown, and generated identical results. Our studies demonstrate that these syngeneic cell lines are relevant preclinical models for testing experimental glioma treatments, and show that IFNα/β is not responsible for the MYXV treatment resistance seen in syngeneic glioma models.

  20. A dual-mediated liposomal drug delivery system targeting the brain: rational construction, integrity evaluation across the blood–brain barrier, and the transporting mechanism to glioma cells

    Science.gov (United States)

    Liu, Chang; Liu, Xiao-Na; Wang, Gui-Ling; Hei, Yu; Meng, Shuai; Yang, Ling-Fei; Yuan, Lan; Xie, Ying

    2017-01-01

    As the global population ages, cancer rates increase worldwide, and degenerative diseases of the central nervous system (CNS), brain tumors, and inflammation threaten human health more frequently. We designed a dual-mediated (receptor-mediated and adsorption-mediated) liposome, named transferrin–cell penetrating peptide–sterically stabilized liposome (TF-CPP-SSL), to improve therapy for gliomas through combining molecular recognition of transferrin receptors (TF-Rs) on the blood–brain barrier (BBB) and glioma cells with the internalization and lysosomal escaping ability of CPP. Based on the systematic investigation of structure–activity relations on the cellular level, we constructed TF-CPP-SSL rationally by conjugating TF and CPP moieties to the liposomes via PEG3.4K and PEG2.0K, respectively, and found the optimum densities of TF and CPP were 1.8% and 4%, respectively. These liposomes had the highest targeting efficacy for brain microvascular endothelial cell and C6 cell uptake but avoided capture by normal cells. Fluorescence resonance energy transfer technology and coculture models of BBB and glioma C6 cells indicated that TF-CPP-SSL was transported across the BBB without drug leakage, liposome breakup, or cleavage of ligand. TF-CPP-SSL offered advantages for crossing the BBB and entering into glioma C6 cells. Real-time confocal viewing revealed that TF-CPP-SSL was entrapped in endosomes of glioma C6 cells and then escaped from lysosomes successfully to release the liposomal contents into the cytosol. Entrapped contents, such as doxorubicin, could then enter the nucleus to exert pharmacological effects. PMID:28405164

  1. Identification of imaging biomarkers for the assessment of tumour response to different treatments in a preclinical glioma model

    Energy Technology Data Exchange (ETDEWEB)

    Lo Dico, A.; Martelli, C. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); Valtorta, S.; Belloli, S. [National Researches Council (CNR), Institute of Molecular Bioimaging and Physiology (IBFM), Segrate, MI (Italy); IRCCS San Raffaele Scientific Institute, Experimental Imaging Center, Milan (Italy); Raccagni, I.; Moresco, R.M. [IRCCS San Raffaele Scientific Institute, Experimental Imaging Center, Milan (Italy); University of Milano-Bicocca, Department of Health Sciences, Monza (Italy); Diceglie, C. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Doctorate School of Molecular Medicine, Milan (Italy); Gianelli, U.; Bosari, S. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Division of Pathology, Milan (Italy); Vaira, V. [Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Division of Pathology, Milan (Italy); Istituto Nazionale Genetica Molecolare ' ' Romeo ed Enrica Invernizzi' ' (INGM), Milan (Italy); Politi, L.S. [IRCCS San Raffaele Scientific Institute, Neuroradiology Department and Neuroradiology Research Group, Milan (Italy); Lucignani, G. [University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); University of Milan, Department of Health Sciences, Milan (Italy); San Paolo Hospital, Department of Diagnostic Services, Unit of Nuclear Medicine, Milan (Italy); Ottobrini, L. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); National Researches Council (CNR), Institute of Molecular Bioimaging and Physiology (IBFM), Segrate, MI (Italy)

    2015-03-27

    Hypoxia-inducible factor 1α (HIF-1α) activity is one of the major players in hypoxia-mediated glioma progression and resistance to therapies, and therefore the focus of this study was the evaluation of HIF-1α modulation in relation to tumour response with the purpose of identifying imaging biomarkers able to document tumour response to treatment in a murine glioma model. U251-HRE-mCherry cells expressing Luciferase under the control of a hypoxia responsive element (HRE) and mCherry under the control of a constitutive promoter were used to assess HIF-1α activity and cell survival after treatment, both in vitro and in vivo, by optical, MRI and positron emission tomography imaging. This cell model can be used to monitor HIF-1α activity after treatment with different drugs modulating transduction pathways involved in its regulation. After temozolomide (TMZ) treatment, HIF-1α activity is early reduced, preceding cell cytotoxicity. Optical imaging allowed monitoring of this process in vivo, and carbonic anhydrase IX (CAIX) expression was identified as a translatable non-invasive biomarker with potential clinical significance. A preliminary in vitro evaluation showed that reduction of HIF-1α activity after TMZ treatment was comparable to the effect of an Hsp90 inhibitor, opening the way for further elucidation of its mechanism of action. The results of this study suggest that the U251-HRE-mCherry cell model can be used for the monitoring of HIF-1α activity through luciferase and CAIX expression. These cells can become a useful tool for the assessment and improvement of new targeted tracers for potential theranostic procedures. (orig.)

  2. β-Asarone promotes Temozolomide's entry into glioma cells and decreases the expression of P-glycoprotein and MDR1.

    Science.gov (United States)

    Wang, Nanbu; Zhang, Qinxin; Ning, Baile; Luo, Laiyu; Fang, Yongqi

    2017-06-01

    Glioma is the most common primary brain tumor and has an undesirable prognosis due to the blood-brain barrier (BBB) and drug resistance. A thorough investigation of the changes in intracellular drug concentrations is important to observe therapeutic effects and cell resistance. P-glycoprotein (P-gp) is an essential protein of Multi-drug resistance 1 (MDR1). The over-expression of P-gp and MDR1 is associated with poor prognosis and drug-resistance in glioma. However, β-asarone can pass through the BBB easily and increase the drug concentration in the rat brain. Our aim is to study the effect of β-asarone on promoting the entry of temozolomide (TMZ) into human glioma U251 cells. The cells were divided into three groups: model group, TMZ group (300μM) and co-administration group (360μM β-asarone; 300μM TMZ). We further detected P-gp and MDR1 expression in U251 and rat glioma C6 cells in four groups: model group (U251/C6), TMZ group (U251 300μM, C6 420μM), β-asarone group (U251 360μM, C6 450μM) and co-administration group (β-asarone 360μM, TMZ 300μM for U251; β-asarone 450μM, TMZ 420μM for C6). Then, high performance liquid chromatography was used to determine the intracellular and extracellular levels of TMZ. Morphological changes in both cells were observed by the microscope. The Counting Kit-8 assay was used to measure the cell proliferation and toxicity. Cell immunohistochemistry/immunofluorescence, flowcytometry and western blot were synchronously used to examine the expression of P-gp. We also determined the levels of MDR1 mRNA by RT-PCR. The results showed that β-asarone could promote the entry of TMZ into U251 cells through the membrane. The co-administration of β-asarone and TMZ also decreased cell proliferation and the expression of P-gp and MDR1 better than single medication in U251 and C6 cells. All of the data suggest that β-asarone might contribute to treatment by promoting TMZ's entry into glioma cells, thereby contributing to anti

  3. Rehabilitation of patients with glioma.

    Science.gov (United States)

    Vargo, Mary; Henriksson, Roger; Salander, Pär

    2016-01-01

    Disabling sequelae occur in a majority of patients diagnosed with brain tumor, including glioma, such as cognitive deficits, weakness, and visual perceptual changes. Often, multiple impairments are present concurrently. Healthcare staff must be aware of the "biographic disruption" the patient with glioma has experienced. While prognostic considerations factor into rehabilitation goals and expectations, regardless of prognosis the treatment team must offer cohesive support, facilitating hope, function, and quality of life. Awareness of family and caregiver concerns plays an important role in the overall care. Inpatient rehabilitation, especially after surgical resection, has been shown to result in functional improvement and homegoing rates on a par with individuals with other neurologic conditions, such as stroke or traumatic brain injury. Community integration comprises a significant element of life satisfaction, as has been shown in childhood glioma survivors. Employment is often affected by the glioma diagnosis, but may be ameliorated, when appropriate, by addressing modifiable factors such as depression, fatigue, or sleep disturbance, or by workplace accommodations. Further research is needed into many facets of rehabilitation in the setting of glioma, including establishing better care models for consistently identifying and addressing functional limitations in this population, measuring outcomes of various levels of rehabilitation care, identifying optimal physical activity strategies, delineating the long-term effects of rehabilitation interventions, and exploring impact of rehabilitation interventions on caregiver burden. The effective elements of cognitive rehabilitation, including transition of cognitive strategies to everyday living, need to be better defined.

  4. 胶质瘤氩氦冻融产物负载树突状细胞对颅内胶质瘤大鼠的免疫治疗研究%Immunotherapy effect of dendritic cells pulsed by lysate of tumor cell Ar-He cryoablation on rat models of intracraniai gliomas

    Institute of Scientific and Technical Information of China (English)

    苏道庆; 卢国辉; 胡丽娟; 王保安; 李明; 何骁征; 姜晓丹; 柯以铨; 张世忠

    2012-01-01

    Objective To investigate the role of C6 glioma cells mediated by rapid freezing and thawing ofAr-He cryoablation in the maturation of marrow-derived dendritic cells (BM-DCs) in Wistar rats,and the anti-tumor effect of these DCs on rat models of intracranial gliomas. Methods C6 glioma cells were routinely cultured in vitro; rapid freezing and thawing of Ar-He cryoablation was employed in C6 glioma cells of the experimental group, and C6 glioma cells of the negative control group were only performed insertion of the probe; blank control group (using rapid freezing and thawing of Ar-He cryoablation on the same amount of PBS) was also employed.Bone marrow-derived mononuclear cells (MNCs) were first prepared from tibia and femur bones of Wistar rats. These cells were cultured with such cytokines as recombinant granulocyte-macrophage colony-stimulating factor (rmGM-CSF),recombinant interleukin-4 (rmIL-4) and tumor necrosis factor-alpha (TNFα) to induce their maturation; BM-DCs were pulsed with or without tumor cell lysate obtained by rapid freezing and thawing of Ar-Hecryoablation at a ratio of (DC:tumor cells =1:3) 7 d after that.Morphological observation of BM-DCs was performed by light microscopy and the expression of DCs costimulatory molecules CD80 and CD86 were measured by flow cytometry 48 h after the addiction; the IL-12 level in the supematant of DCs was detected by ELISA. In order to determine whether or not vaccination with C6 TP DCs can induce the therapeutic potential in the established glioma-bearing models, the C6 cells cultured in vitro were stereotaxically implanted into the left caudate nucleus of Wistar rat brain; glioma-bearing rats were injected with vaccination with DCs,cells from the blank control group and negative control group on the 3rd and 10th d. Survival time was observed and determined using the method of Kaplan-Meier and Log-Rank analysis. Results DCs from rats' bone marrow cells cultured with cytokines and pulsed with tumor lysates

  5. A Mathematical Model for Simultaneous Saccharification and Co-fermentation (SSCF) of C6 and C5 Sugars%六碳糖和五碳糖同步糖化与共发酵的数学模型

    Institute of Scientific and Technical Information of China (English)

    R.Morales-Rodriguez; K.V.Gernaey; A.S.Meyer; G.Sin

    2011-01-01

    Reliable production of biofuels and specifically bioethanol has attracted a significant amount of research recently. Within this context, this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation (SSCF) of C6 and C5 sugars. The model is constructed by combining existing mathematical models for enzymatic hydrolysis and co-fermentation. An inhhibition of ethanol on cellulose conversion is introduced in order to increase the reliability. The mathematical model for the SSCF is verified by comparing the model predictions with experimental data obtained from the ethanol production based on kraft paper mill sludge. When fitting the model to the data, only the yield coefficients for glucose and xylose metabolism were fine-tuned, which were found to be 0.43 g.g-1 (ethanol/glucose) and 0.35 g.g-1 (ethanol/xylose) respectively. These promising validation results encourage further model application to evaluate different process configurations for lignocellulosic biooethanol technology.

  6. The study of 12C(α,γ astrophysical reaction using 12C(6Li,d and 12C(7Li,t reaction at 20 MeV and in the framework of the potential model

    Directory of Open Access Journals (Sweden)

    Adhikari S.

    2015-01-01

    Full Text Available The triton angular distribution in the 12C(7Li,t16O reaction has been measured at 20 MeV incident energy. Comparison of the data with Finite Range DWBA and CDCC-CRC calculations show that breakup coupling effects are prominent in the transfer to the ground state. This observation is similar to that in the 12C(6Li,d reaction at the same incident energy. The alpha spectroscopic factor of the 16O ground state is determined (Sα=0.25 from a comparison of the measured angular distribution with respect to the CDCC-CRC calculations. The E2 S-factor of the 12C(α,γ reaction at 300 keV in the framework of a potential model is determined to be about 118 keV-barn.

  7. 3-Bromopyruvate antagonizes effects of lactate and pyruvate, synergizes with citrate and exerts novel anti-glioma effects.

    Science.gov (United States)

    El Sayed, S M; El-Magd, R M Abou; Shishido, Y; Chung, S P; Diem, T H; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

    2012-02-01

    Oxidative stress-energy depletion therapy using oxidative stress induced by D-amino acid oxidase (DAO) and energy depletion induced by 3-bromopyruvate (3BP) was reported recently (El Sayed et al., Cancer Gene Ther., 19, 1-18, 2012). Even in the presence of oxygen, cancer cells oxidize glucose preferentially to produce lactate (Warburg effect) which seems vital for cancer microenvironment and progression. 3BP is a closely related structure to lactate and pyruvate and may antagonize their effects as a novel mechanism of its action. Pyruvate exerted a potent H(2)O(2) scavenging effect to exogenous H(2)O(2), while lactate had no scavenging effect. 3BP induced H(2)O(2) production. Pyruvate protected against H(2)O(2)-induced C6 glioma cell death, 3BP-induced C6 glioma cell death but not against DAO/D-serine-induced cell death, while lactate had no protecting effect. Lactate and pyruvate protected against 3BP-induced C6 glioma cell death and energy depletion which were overcome with higher doses of 3BP. Lactate and pyruvate enhanced migratory power of C6 glioma which was blocked by 3BP. Pyruvate and lactate did not protect against C6 glioma cell death induced by other glycolytic inhibitors e.g. citrate (inhibitor of phosphofructokinase) and sodium fluoride (inhibitor of enolase). Serial doses of 3BP were synergistic with citrate in decreasing viability of C6 glioma cells and spheroids. Glycolysis subjected to double inhibition using 3BP with citrate depleted ATP, clonogenic power and migratory power of C6 glioma cells. 3BP induced a caspase-dependent cell death in C6 glioma. 3BP was powerful in decreasing viability of human glioblastoma multiforme cells (U373MG) and C6 glioma in a dose- and time-dependent manner.

  8. PET imaging of brain with the {beta}-amyloid probe, [{sup 11}C]6-OH-BTA-1, in a transgenic mouse model of Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Toyama, Hiroshi [Fujita Health University, Department of Radiology, Aichi (Japan); National Institutes of Health, Molecular Imaging Branch, National Institute of Mental Health, Bethesda, Maryland (United States); Ye, Daniel; Cohen, Robert M. [National Institutes of Health, Geriatric Psychiatry Branch, National Institute of Mental Health, Bethesda, Maryland (United States); Ichise, Masanori; Liow, Jeih-San; Cai, Lisheng; Musachio, John L.; Hong, Jinsoo; Crescenzo, Mathew; Tipre, Dnyanesh; Lu, Jian-Qiang; Zoghbi, Sami; Vines, Douglass C.; Pike, Victor W.; Innis, Robert B. [National Institutes of Health, Molecular Imaging Branch, National Institute of Mental Health, Bethesda, Maryland (United States); Jacobowitz, David [USUHS, Department of Anatomy, Physiology, and Genetics, Bethesda, Maryland (United States); Seidel, Jurgen; Green, Michael V. [National Institutes of Health, Department of Nuclear Medicine, Warren Grant Magnuson Clinical Center, Bethesda, Maryland (United States); Katada, Kazuhiro [Fujita Health University, Department of Radiology, Aichi (Japan)

    2005-04-01

    The purpose of this study was to evaluate the capacity of [{sup 11}C]6-OH-BTA-1 and positron emission tomography (PET) to quantify {beta}-amyloid (A{beta}) plaques in the Tg2576 mouse model of Alzheimer's disease (AD). PET imaging was performed with the NIH ATLAS small animal scanner in six elderly transgenic mice (Tg2576; age 22.0{+-}1.8 months; 23.6{+-}2.6 g) overexpressing a mutated form of human {beta}-amyloid precursor protein (APP) known to result in the production of A{beta} plaques, and in six elderly wild-type litter mates (age 21.8{+-}1.6 months; 29.5{+-}4.7 g). Dynamic PET scans were performed for 30 min in each mouse under 1% isoflurane inhalation anesthesia after a bolus injection of 13-46 MBq of [{sup 11}C]6-OH-BTA-1. PET data were reconstructed with 3D OSEM. On the coronal PET image, irregular regions of interest (ROIs) were placed on frontal cortex (FR), parietal cortex (PA), striatum (ST), thalamus (TH), pons (PO), and cerebellum (CE), guided by a mouse stereotaxic atlas. Time-activity curves (TACs) (expressed as percent injected dose per gram normalized to body weight: % ID-kg/g) were obtained for FR, PA, ST, TH, PO, and CE. ROI-to-CE radioactivity ratios were also calculated. Following PET scans, sections of mouse brain prepared from anesthetized and fixative-perfused mice were stained with thioflavin-S. TACs for [{sup 11}C]6-OH-BTA-1 in all ROIs peaked early (at 30-55 s), with radioactivity washing out quickly thereafter in both transgenic and wild-type mice. Peak uptake in all regions was significantly lower in transgenic mice than in wild-type mice. During the later part of the washout phase (12-30 min), the mean FR/CE and PA/CE ratios were higher in transgenic than in wild-type mice (1.06{+-}0.04 vs 0.98{+-}0.07, p=0.04; 1.06{+-}0.09 vs 0.93{+-}0.08 p=0.02) while ST/CE, TH/CE, and PO/CE ratios were not. Ex vivo staining revealed widespread A{beta} plaques in cortex, but not in cerebellum of transgenic mice or in any brain regions of wild

  9. Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells-Characterization of a New in Vivo Model

    National Research Council Canada - National Science Library

    Stojković, Sonja; Podolski-Renić, Ana; Dinić, Jelena; Pavković, Željko; Ayuso, Jose M; Fernández, Luis J; Ochoa, Ignacio; Pérez-García, Victor M; Pešić, Vesna; Pešić, Milica

    2016-01-01

    .... Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and temozolomide (TMZ...

  10. Predicting in vivo glioma growth with the reaction diffusion equation constrained by quantitative magnetic resonance imaging data

    Science.gov (United States)

    Hormuth, David A., II; Weis, Jared A.; Barnes, Stephanie L.; Miga, Michael I.; Rericha, Erin C.; Quaranta, Vito; Yankeelov, Thomas E.

    2015-07-01

    Reaction-diffusion models have been widely used to model glioma growth. However, it has not been shown how accurately this model can predict future tumor status using model parameters (i.e., tumor cell diffusion and proliferation) estimated from quantitative in vivo imaging data. To this end, we used in silico studies to develop the methods needed to accurately estimate tumor specific reaction-diffusion model parameters, and then tested the accuracy with which these parameters can predict future growth. The analogous study was then performed in a murine model of glioma growth. The parameter estimation approach was tested using an in silico tumor ‘grown’ for ten days as dictated by the reaction-diffusion equation. Parameters were estimated from early time points and used to predict subsequent growth. Prediction accuracy was assessed at global (total volume and Dice value) and local (concordance correlation coefficient, CCC) levels. Guided by the in silico study, rats (n = 9) with C6 gliomas, imaged with diffusion weighted magnetic resonance imaging, were used to evaluate the model’s accuracy for predicting in vivo tumor growth. The in silico study resulted in low global (tumor volume error 0.92) and local (CCC values >0.80) level errors for predictions up to six days into the future. The in vivo study showed higher global (tumor volume error >11.7%, Dice silico study shows that model parameters can be accurately estimated and used to accurately predict future tumor growth at both the global and local scale. However, the poor predictive accuracy in the experimental study suggests the reaction-diffusion equation is an incomplete description of in vivo C6 glioma biology and may require further modeling of intra-tumor interactions including segmentation of (for example) proliferative and necrotic regions.

  11. In vitro anticancer drug test: A new method emerges from the model of glioma stem cells

    Directory of Open Access Journals (Sweden)

    Gabriele Riva

    2014-01-01

    Full Text Available Glioblastoma multiforme (GBM is a grade IV astrocytoma and the most common malignant brain tumor. Current therapies provide a median survival of 12–15 months after diagnosis, due to the high recurrence rate. The failure of current therapies may be due to the presence, within the tumor, of cells characterized by enhanced self-renewal capacity, multilineage differentiation potential and elevated invasive behavior, called glioma stem cells (GSCs. To evaluate the pharmacological efficacy of selected drugs on six GSC lines, we set up a multiple drug responsivity assay based on the combined evaluation of cytomorphological and functional parameters, including the analysis of polymorphic nuclei, mitotic index and cell viability. In order to understand the real pharmacological efficacy of the tested drugs, we assigned a specific drug responsivity score to each GSC line, integrating the data produced by multiple assays. In this work we explored the antineoplastic effects of paclitaxel (PTX, an inhibitor of microtubule depolymerization, utilized as standard treatment in several cancers, and of valproic acid (VPA, an inhibitor of histone deacetylases (HDACs with multiple anticancer properties. We classified the six GSC lines as responsive or resistant to these drugs, on the basis of their responsivity scores. This method can also be useful to identify the best way to combine two or more drugs. In particular, we utilized the pro-differentiating effect of VPA to improve the PTX effectiveness and we observed a significant reduction of cell viability compared to single treatments.

  12. Efficacy and safety/toxicity study of recombinant vaccinia virus JX-594 in two immunocompetent animal models of glioma.

    Science.gov (United States)

    Lun, XueQing; Chan, Jennifer; Zhou, Hongyuan; Sun, Beichen; Kelly, John J P; Stechishin, Owen Owen; Bell, John C; Parato, Kelley; Hu, Kang; Vaillant, Dominique; Wang, Jiahu; Liu, Ta-Chiang; Breitbach, Caroline; Kirn, David; Senger, Donna L; Forsyth, Peter A

    2010-11-01

    The purpose of this study was to investigate the oncolytic potential of the recombinant, granulocyte macrophage colony-stimulating factor (GM-CSF)-expressing vaccinia virus (VV) JX-594 in experimental malignant glioma (MGs) in vitro and in immunocompetent rodent models. We have found that JX-594 killed all MG cell lines tested in vitro. Intratumoral (i.t.) administration of JX-594 significantly inhibited tumor growth and prolonged survival in rats-bearing RG2 intracranial (i.c.) tumors and mice-bearing GL261 brain tumors. Combination therapy with JX-594 and rapamycin significantly increased viral replication and further prolonged survival in both immunocompetent i.c. MG models with several animals considered "cured" (three out of seven rats >120 days, terminated experiment). JX-594 infected and killed brain tumor-initiating cells (BTICs) from patient samples grown ex vivo, and did so more efficiently than other oncolytic viruses MYXV, Reovirus type-3, and VSV(ΔM51). Additional safety/toxicity studies in nontumor-bearing rodents treated with a supratherapeutic dose of JX-594 demonstrated GM-CSF-dependent inflammation and necrosis. These results suggest that i.c. administered JX-594 triggers a predictable GM-CSF-mediated inflammation in murine models. Before proceeding to clinical trials, JX-594 should be evaluated in the brains of nonhuman primates and optimized for the viral doses, delivery routes as well as the combination agents (e.g., mTOR inhibitors).

  13. Epidemiology of gliomas.

    Science.gov (United States)

    Ostrom, Quinn T; Gittleman, Haley; Stetson, Lindsay; Virk, Selene M; Barnholtz-Sloan, Jill S

    2015-01-01

    Gliomas are the most common type of primary intracranial tumors. Some glioma subtypes cause significant mortality and morbidity that are disproportionate to their relatively rare incidence. A very small proportion of glioma cases can be attributed to inherited genetic disorders. Many potential risk factors for glioma have been studied to date, but few provide explanation for the number of brain tumors identified. The most significant of these factors includes increased risk due to exposure to ionizing radiation, and decreased risk with history of allergy or atopic disease. The potential effect of exposure to cellular phones has been studied extensively, but the results remain inconclusive. Recent genomic analyses, using the genome-wide association study (GWAS) design, have identified several inherited risk variants that are associated with increased glioma risk. The following chapter provides an overview of the current state of research in the epidemiology of intracranial glioma.

  14. Low-fluence rate, long duration photodynamic therapy in glioma mouse model using organic light emitting diode (OLED).

    Science.gov (United States)

    Guo, Han-Wen; Lin, Liang-Ting; Chen, Po-Hsiung; Ho, Meng-Huan; Huang, Wan-Ting; Lee, Yi-Jang; Chiou, Shih-Hwa; Hsieh, Yei-San; Dong, Chen-Yuan; Wang, Hsing-Wen

    2015-09-01

    The treatment of gliomas poses significant clinical challenges due to resistance to chemo and radiation therapy, and treatment side effects. Metronomic photodynamic therapy (mPDT), which involves long treatment time with low fluence rate and multiple or continuous photosensitizer administrations, has potential in treating gliomas without threatening the quality of life and has been demonstrated in rats and rabbits. mPDT in small animals such as mouse is not yet shown due to lack of lightweight illumination device for long periods of time. We presented low fluence rate (3mW/cm(2)) and long duration (3.7h) PDT treatment in a nude mouse model of human glioblastoma by using organic light emitting diode (OLED) with single dose of 5-aminolevulinic acid (ALA) administration as photosensitizer. Tumor volume was measured using bioluminescent imaging and the animal survival time was recorded. Additionally, we have performed limited PDT dosimetric measurements of PpIX fluorescence, tumor oxygenation and hemoglobin concentration in 3 PDT mice. For animals with similar pre- and immediate post-light tumor volume, the averaged total survival time of PDT mice is 40.5±9.2 days that are significantly longer than the control mice (26.0±2.0 days). The post-light survival time of PDT mice is 14.3±5.9 days that are marginally longer than the control group (8.0±0.0 days). In the dosimetric measurement, good maintenance of PpIX fluorescence in one PDT mouse has relatively improved survival time, compared with the other two PDT mice (i.e., 24 days versus 16 and 17 days). This pilot study demonstrated the feasibility of low-fluence rate and long treatment time of ALA-PDT using OLED without anesthetization of animals. The response of PDT treated animals with similar pre- and post-light tumor volume is encouraging to show a longer survival time than the controls. The dosimetric indices such as photosensitizer fluorescence and tissue oxygenation would help understand the possible treatment

  15. RETROVIRAL-MEDIATED SUICIDE GENE THERAPY OF EXPERIMENTAL GLIOMA

    Institute of Scientific and Technical Information of China (English)

    Xu Lingfei; Ge Kai; Zheng Zhongcheng; Sun Lanying; Liu Xinyuan

    1998-01-01

    Objective: To establish a retroviral-mediated suicide gene therapy system for experimental glioma and test its efficacy. Methods: C6 rat glioma cells were infected with recombinant retrovirus containing HSV-tk gene. The C6/tk cell line which stably expressed tk was selected and cloned. The sensitivities of C6/tk cells to several nucleoside analogues, such as GCV, BVdU, ACV were compared by the growth inhibition studies. Antitumor effects were also observed after GCV treatment in nude mice bearing tumors derived from C6/tk cells. Results:The growth inhibition studies showed that GCV was the most efficient prodrug in this system. C6/tk cells were highly sensitive to GCV, with an IC50<0.2 μmol/L, being 500-fold less than that in tk-negative C6 cells. In vivo studies showed significant tumor inhibition in the treatment group. Conclusion: Glioma cells can be eradicated by using retroviral-mediated suicide gene system in vitro as well as in vivo.

  16. Temporal dynamic changes of connexin 43 expression in C6 cells following lipopolysaccharide stimulation

    Institute of Scientific and Technical Information of China (English)

    Ling Liu; Haiyan Liu; Zhenping Gao; Linbo Zhang; Lue Su; Guojun Dong; Haiyang Yu; Jiayi Tian; Hang Zhao; Yanyan Xu

    2012-01-01

    Connexin 43, a gap junction protein, is expressed mainly in glia in the central nervous system.Neuroinflammation plays an important role in central nervous system injury. Changes to glial connexin 43 levels and neuroinflammation may trigger brain injury and neurodegenerative diseases.To illustrate the relationship between connexin 43 and neuroinflammation, this study investigated how connexin 43 expression levels change in lipopolysaccharide-stimulated rat C6 glioma cells. C6 cells were treated with 0.05, 0.25, 0.5, 1, 2.5 and 5 μg/mL lipopolysaccharide for 24 hours. The nitrite estimation-detected nitric oxide release level was elevated substantially after lipopolysaccharide stimulation. To test the transcriptional level changes of inducible nitric oxide synthase, tumor necrosis factor-α and connexin 43 mRNA, C6 cells were treated with 5 μg/mL lipopolysaccharide for 3-48 hours. Reverse transcription-PCR showed that the expression of inducible nitric oxide synthase and tumor necrosis factor-α mRNA increased over time, but connexin 43 mRNA levels increased in lipopolysaccharide-stimulated C6 cells at 3 and 6 hours, and then decreased from 12 to 48 hours. Connexin 43 protein expression was detected by immunofluorescence staining, and the protein levels matched the mRNA expression levels. These results suggest that connexin 43 expression is biphasic in lipopolysaccharide-inducedneuroinflammation in C6 cells, which may be correlated with the connexin 43 compensatorymechanism.

  17. Cinnamon polyphenols regulate S100ß, sirtuins, and neuroactive proteins in rat C6 glioma cells

    Science.gov (United States)

    Dietary polyphenols exert neuroprotective effects in a variety of brain disorders, including Alzheimer’s disease, ischemia/stroke, and Parkinson’s disease. The protective effects of polyphenols in the brain and in neural cell cultures have been established. The role of glial cells in providing prote...

  18. Evaluation of 188Re-labeled PEGylated nanoliposome as a radionuclide therapeutic agent in an orthotopic glioma-bearing rat model

    Directory of Open Access Journals (Sweden)

    Huang FYJ

    2015-01-01

    Full Text Available Feng-Yun J Huang,1 Te-Wei Lee,2 Chih-Hsien Chang,2 Liang-Cheng Chen,2 Wei-Hsin Hsu,2 Chien-Wen Chang,1 Jem-Mau Lo1 1Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan; 2Institute of Nuclear Energy Research, Longtan, Taiwan Purpose: In this study, the 188Re-labeled PEGylated nanoliposome (188Re-liposome was prepared and evaluated as a therapeutic agent for glioma.Materials and methods: The reporter cell line, F98luc was prepared via Lentivector expression kit system and used to set up the orthotopic glioma-bearing rat model for non-invasive bioluminescent imaging. The maximum tolerated dose applicable in Fischer344 rats was explored via body weight monitoring of the rats after single intravenous injection of 188Re-liposome with varying dosages before the treatment study. The OLINDA/EXM 1.1 software was utilized for estimating the radiation dosimetry. To assess the therapeutic efficacy, tumor-bearing rats were intravenously administered 188Re-liposome or normal saline followed by monitoring of the tumor growth and animal survival time. In addition, the histopathological examinations of tumors were conducted on the 188Re-liposome-treated rats.Results: By using bioluminescent imaging, the well-established reporter cell line (F98luc showed a high relationship between cell number and its bioluminescent intensity (R2=0.99 in vitro; furthermore, it could also provide clear tumor imaging for monitoring tumor growth in vivo. The maximum tolerated dose of 188Re-liposome in Fischer344 rats was estimated to be 333 MBq. According to the dosimetry results, higher equivalent doses were observed in spleen and kidneys while very less were in normal brain, red marrow, and thyroid. For therapeutic efficacy study, the progression of tumor growth in terms of tumor volume and/or tumor weight was significantly slower for the 188Re-liposome-treated group than the control group (P<0.05. As a result, the

  19. Suppression of glioma progression by Egln3.

    Directory of Open Access Journals (Sweden)

    Vicki A Sciorra

    Full Text Available Grade IV astrocytoma or glioblastoma has a poor clinical outcome that can be linked to hypoxia, invasiveness and active vascular remodeling. It has recently been suggested that hypoxia-inducible factors, Hifs, increase glioma growth and aggressiveness [1], [2], [3]. Here, we tested the hypothesis that Egl 9 homolog 3 (Egln3, a prolyl-hydroxylase that promotes Hif degradation, suppresses tumor progression of human and rodent glioma models. Through intracranial tumorigenesis and in vitro assays, we demonstrate for the first time that Egln3 was sufficient to decrease the kinetics of tumor progression and increase survival. We also find that Klf5, a transcription factor important to vascular remodeling, was regulated by hypoxia in glioma. An analysis of the tumor vasculature revealed that elevated Egln3 normalized glioma capillary architecture, consistent with a role for Egln3 in eliciting decreases in the production of Hif-regulated, angiogenic factors. We also find that the hydroxylase-deficient mutant, Egln3(H196A partially maintained tumor suppressive activity. These results highlight a bifurcation of Egln3 signaling and suggest that Egln3 has a non-hydroxylase-dependent function in glioma. We conclude that Egln3 is a critical determinant of glioma formation and tumor vascular functionality.

  20. The experimental investigation of glioma-trophic capacity of human umbilical cord-derived mesenchymal stem cells after intraventricular administration

    Directory of Open Access Journals (Sweden)

    FAN Cun-gang

    2013-07-01

    Full Text Available Objective To explore the glioma-trophic migration capacity of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs by intraventricular administration. Methods The umbilical cord tissue were obtained during full-term pregnancy cesarean section under sterile conditions. This study was approved by Ethics Committee and got the informed consent of patient. The hUC-MSCs were isolated by trypsin and collagenase digestion, followed by adherent culture methods. The characteristics of isolated hUC-MSCs were demonstrated by cell morphylogy, phenotype analysis and multi-differentiation potentials into adipocytes, osteoblasts and neural cells. Then the hUC-MSCs were labeled with CM-DiI and injected into contralateral ventricle of glioma of the C6 glioma-bearing Sprague-Dawley (SD rats. Two weeks later, the rats were sacrificed and the brains were taken out to examine the migration and distribution of hUC-MSCs in the tumor bed, at the interface of tumor and cerebral parenchyma as well as the tumor satelites infiltrating into the normal brain. Results The hUC-MSCs demonstrated plastic-adherent characterization and homogeneous fibroblastic-like morphylogy in culture, expression of specific surface phenotypes of MSCs (CD13, CD29, CD44, CD90 but not endothelial or hematopoietic markers (CD14, CD31, CD34, CD38, CD45, CD133, and muti-differentiatiation potentials into Oil red O stained adipocytes, Alizarin red S stained osteoblasts, neuron-specific enolase (NSE-positive neurons and glial fibrillary acidic protein (GFAP-positive astrocytes in permissive inducive conditions. Importantly, after labeled hUC-MSCs injection into contralateral ventricle of glioma, the hUC-MSCs migrated from initial injection site to the glioma mass and along the interface of tumor and brain, and some of them "chasing" the glioma satellites infiltrated into the normal parenchyma. Conclusion The hUC-MSCs possess prominent tumor-specific targeting capacity and extensive intratumoral

  1. 替莫唑胺对胶质瘤侵袭性的影响及可能机制%Effect of temozolomide on the glioma invasiveness and its possible mechanism

    Institute of Scientific and Technical Information of China (English)

    王健; 贾永森; 赵喜庆; 秦丽娟

    2014-01-01

    目的:探讨肿瘤坏死因子-α( tumor necrosis factor-α, TNF-α)在替莫唑胺( temozolomide, TMZ)降低胶质瘤侵袭性过程中的作用及机制。方法对数生长期的C6胶质瘤细胞随机分为TMZ处理10、30、60、120、180和240 min组,每组各15例,动态监测培养液中TNF-α的含量(放射免疫法)、C6细胞内 p53蛋白的表达( Western blot法)和细胞凋亡水平( AnnexinV-FITC法)。制备体外胶质瘤的侵袭模型,利用结晶紫染色法检测胶质瘤的侵袭性。结果 TMZ作用于C6细胞后,培养液中TNF-α的含量明显增加,于120 min时含量最多(P<0.01),其后开始减少。 C6细胞内p53蛋白的表达于处理后120 min达高峰(P<0.01),其后逐渐减少。 TMZ作用于体外胶质瘤侵袭模型后,胶质瘤细胞的侵袭性降低。结论 TNF-α介导TMZ降低胶质瘤侵袭性,此作用可能是由于TMZ促进C6细胞释放TNF-α,增加的TNF-α又促进胶质瘤细胞凋亡所致。%Purpose To explore the role of tumor necrosis factor-α( TNF-α) in the process of temozolomide ( TMZ) reduce glioma in-vasiveness and its possible mechanism. Methods C6 glioma cells of logarithmic phase were randomly divided into TMZ treatment (10, 30, 60, 120, 180, 240 min group) (n=15), dynamic monitoring content of TNF-αin the culture medium was measured by ra-dioimmunoassay, expression of p53 protein in C6 cells was detected with Western blotting method, and cell apoptosis was used with AnnexinV-FITC. A glioma invasiveness model was established in vitro and glioma invasiveness was determined by crystal violet stai-ning. Results For C6 cells, contents of TNF-αin the nutrient fluid and expressions of p53 protein in C6 cells obviously increased af-ter TMZ treatment and they achieved the peak at 120 min (P<0. 01), followed by decrease gradually. Glioma invasiveness was re-duced after TMZ acted on glioma in vitro. Conclusion TMZ can reduce glioma invasiveness by TNF-α, which this role may be is TMZ promote C6

  2. Gamma knife treatment of rat glioma Influences of irradiation dose on apoptosis and necrosis

    Institute of Scientific and Technical Information of China (English)

    Peng Wang; Mianshun Pan; Xinggen Fang

    2008-01-01

    BACKGROUND: Apoptosis and necrosis are cellular death mechanisms that are induced in glioma cells following gamma knife irradiation. Increased apoptosis is essential for maintaining and enhancing treatment efficacy.OBJECTIVE: To observe apoptotic and necrotic mechanisms of rat glioma models induced by gamma knife treatment and to analyze the influences of irradiation doses on apoptosis and necrosis. DESIGN: Controlled animal experiment. SETTING: Cancer Hospital of Tianjin Medical University and Gamma Knife Center of Hefei Brain Hospital.MATERIALS: Eighteen female specific pathogen free Sprague Dawley rats, weighing 180-210 g and 5-6 weeks old, were purchased from the Experimental Animal Center, Medical College of Suzhou University. Rat C6 glioma cells were purchased from the cell bank of Chinese Academy of Sciences. Annexin V-FITC Reagent Kit (Bender Med System. Company, USA) and a flow cytometer (Becton Dickinson FACSCalibur) were provided.METHODS: The experiment was conducted at the Cancer Hospital of Tianjin Medical University and Gamma Knife Center of Hefei Brain Hospital from December 2006 to May 2007. All rats were inoculated with C6 glioma cells, i.e., 4 μL of a C6 glioma cell suspension was injected 5 mm deep in the cortex. All rats were divided randomly into a model group, 9-Gy treatment group, and 12-Gy treatment group. There were six rats in each group.MAIN OUTCOME MEASURES: Apoptosis and necrosis of normal brain tissue and glioma were observed by Flow Cytometry one week after irradiation, and pathological changes to tumor tissue were identified by HE staining.RESULTS: Eighteen rats were initially selected for the study: two rats from the model and 12-Gy treatment groups died from accidental anesthesia. The remaining 16 rats were included in the final result analysis. Cellular apoptosis and necrosis: apoptosis and necrosis were significantly increased in the treatment groups after gamma knife irradiation, compared to the model group (P < 0

  3. The Pathobiology of Glioma Tumors

    OpenAIRE

    Gladson, Candece L.; Prayson, Richard A.; LIU Wei

    2010-01-01

    The ongoing characterization of the genetic and epigenetic alterations in the gliomas has already improved the classification of these heterogeneous tumors and enabled the development of rodent models for analysis of the molecular pathways underlying their proliferative and invasive behavior. Effective application of the targeted therapies that are now in development will depend on pathologists’ ability to provide accurate information regarding the genetic alterations and the expression of ke...

  4. Improved efficacy and reduced toxicity of doxorubicin encapsulated in sulfatide-containing nanoliposome in a glioma model.

    Directory of Open Access Journals (Sweden)

    Jia Lin

    Full Text Available As a glycosphingolipid that can bind to several extracellular matrix proteins, sulfatide has the potential to become an effective targeting agent for tumors overexpressing tenasin-C in their microenvironment. To overcome the dose-limiting toxicity of doxorubicin (DOX, a sulfatide-containing nanoliposome (SCN encapsulation approach was employed to improve treatment efficacy and reduce side effects of free DOX. This study analysed in vitro characteristics of sulfatide-containing nanoliposomal DOX (SCN-DOX and assessed its cytotoxicity in vitro, as well as biodistribution, therapeutic efficacy, and systemic toxicity in a human glioblastoma U-118MG xenograft model. SCN-DOX was shown to achieve highest drug to lipid ratio (0.5∶1 and a remarkable in vitro stability. Moreover, DOX encapsulated in SCN was shown to be delivered into the nuclei and displayed prolonged retention over free DOX in U-118MG cells. This simple two-lipid SCN-DOX nanodrug has favourable pharmacokinetic attributes in terms of prolonged circulation time, reduced volume of distribution and enhanced bioavailability in healthy rats. As a result of the improved biodistribution, an enhanced treatment efficacy of SCN-DOX was found in glioma-bearing mice compared to the free drug. Finally, a reduction in the accumulation of DOX in the drug's principal toxicity organs achieved by SCN-DOX led to the diminished systemic toxicity as evident from the plasma biochemical analyses. Thus, SCN has the potential to be an effective and safer nano-carrier for targeted delivery of therapeutic agents to tumors with elevated expression of tenascin-C in their microenvironment.

  5. The pathobiology of glioma tumors.

    Science.gov (United States)

    Gladson, Candece L; Prayson, Richard A; Liu, Wei Michael

    2010-01-01

    The ongoing characterization of the genetic and epigenetic alterations in the gliomas has already improved the classification of these heterogeneous tumors and enabled the development of rodent models for analysis of the molecular pathways underlying their proliferative and invasive behavior. Effective application of the targeted therapies that are now in development will depend on pathologists' ability to provide accurate information regarding the genetic alterations and the expression of key receptors and ligands in the tumors. Here we review the mechanisms that have been implicated in the pathogenesis of the gliomas and provide examples of the cooperative nature of the pathways involved, which may influence the initial therapeutic response and the potential for development of resistance.

  6. Sustained radiosensitization of hypoxic glioma cells after oxygen pretreatment in an animal model of glioblastoma and in vitro models of tumor hypoxia.

    Science.gov (United States)

    Clarke, Ryon H; Moosa, Shayan; Anzivino, Matthew; Wang, Yi; Floyd, Desiree Hunt; Purow, Benjamin W; Lee, Kevin S

    2014-01-01

    Glioblastoma multiforme (GBM) is the most common and lethal form of brain cancer and these tumors are highly resistant to chemo- and radiotherapy. Radioresistance is thought to result from a paucity of molecular oxygen in hypoxic tumor regions, resulting in reduced DNA damage and enhanced cellular defense mechanisms. Efforts to counteract tumor hypoxia during radiotherapy are limited by an attendant increase in the sensitivity of healthy brain tissue to radiation. However, the presence of heightened levels of molecular oxygen during radiotherapy, while conventionally deemed critical for adjuvant oxygen therapy to sensitize hypoxic tumor tissue, might not actually be necessary. We evaluated the concept that pre-treating tumor tissue by transiently elevating tissue oxygenation prior to radiation exposure could increase the efficacy of radiotherapy, even when radiotherapy is administered after the return of tumor tissue oxygen to hypoxic baseline levels. Using nude mice bearing intracranial U87-luciferase xenografts, and in vitro models of tumor hypoxia, the efficacy of oxygen pretreatment for producing radiosensitization was tested. Oxygen-induced radiosensitization of tumor tissue was observed in GBM xenografts, as seen by suppression of tumor growth and increased survival. Additionally, rodent and human glioma cells, and human glioma stem cells, exhibited prolonged enhanced vulnerability to radiation after oxygen pretreatment in vitro, even when radiation was delivered under hypoxic conditions. Over-expression of HIF-1α reduced this radiosensitization, indicating that this effect is mediated, in part, via a change in HIF-1-dependent mechanisms. Importantly, an identical duration of transient hyperoxic exposure does not sensitize normal human astrocytes to radiation in vitro. Taken together, these results indicate that briefly pre-treating tumors with elevated levels of oxygen prior to radiotherapy may represent a means for selectively targeting radiation

  7. Probing the Bi-directional Interaction Between Microglia and Gliomas in a Tumor Microenvironment on a Microdevice.

    Science.gov (United States)

    Gu, Rui; Zhang, Xu; Zhang, Ge; Tao, Tingting; Yu, Haibo; Liu, Lianqing; Dou, Ying; Li, Aiping; Qin, Jianhua

    2017-02-24

    It has been proven that microglia are involved in both early and late stages of glioma progression and contribute substantially to the tumor mass of gliomas. Because no appropriate in vitro or in vivo investigative approach is available, the dynamic interaction between microglia and gliomas during tumor formation remains unclear. In this study, three types of microfluidic assay were developed to examine the outcomes of the dynamic interaction between microglia and gliomas. Co-migration assay and two-dimensional cell co-culture assay have been used to show that microglial BV-2 cells migrate toward C6 glioma cells and inhibit tumor growth during the early stage of tumorigenesis. However, in three-dimensional cell spheres (three-dimensional cell co-culture assay) that contain a large amount of glioma cells, mimicking the late stage of glioma growth, the phagocytosis of microglia was suppressed, which suggests that glioma cells could reeducate classically activated microglia into a tumor-promoting state at some point during tumor progression. Notably, we found that microglia could contribute to tumor invasion and acquisition of the epithelial-mesenchymal transition phenotype in the glioma microenvironment during the early stage and the late stage of tumor progression. In conclusion, we have developed a potential quantitative method for in vitro study of glioma immunity and provided evidence for the duality of glioma-associated microglia.

  8. Density-dependent quiescence in glioma invasion: instability in a simple reaction–diffusion model for the migration/proliferation dichotomy

    KAUST Repository

    Pham, Kara

    2012-01-01

    Gliomas are very aggressive brain tumours, in which tumour cells gain the ability to penetrate the surrounding normal tissue. The invasion mechanisms of this type of tumour remain to be elucidated. Our work is motivated by the migration/proliferation dichotomy (go-or-grow) hypothesis, i.e. the antagonistic migratory and proliferating cellular behaviours in a cell population, which may play a central role in these tumours. In this paper, we formulate a simple go-or-grow model to investigate the dynamics of a population of glioma cells for which the switch from a migratory to a proliferating phenotype (and vice versa) depends on the local cell density. The model consists of two reaction-diffusion equations describing cell migration, proliferation and a phenotypic switch. We use a combination of numerical and analytical techniques to characterize the development of spatio-temporal instabilities and travelling wave solutions generated by our model. We demonstrate that the density-dependent go-or-grow mechanism can produce complex dynamics similar to those associated with tumour heterogeneity and invasion.

  9. Extract from Buthus martensii Karsch is associated with potassium channels on glioma cells

    Institute of Scientific and Technical Information of China (English)

    Mingxian Li; Hongmei Meng; Shao Wang; Min Huang; Li Cui; Weihong Lin

    2011-01-01

    Catilan extracted from Leiurus quinquestriatus is a specific ion channel blocker.It can specifically bind chloride channels of glioma cells and kill these tumor cells.The questions remain as to whether antigliomatin,the extract from scorpion venom of Buthus martensii Karsch in China,can inhibit glioma growth,and whether this inhibition is correlated with ion channels of tumor cells.The present study treated rat C6 glioma cells with 0.8,1.2,and 1.6 μg/mL antigliomatin for 20 hours.Whole-cell patch clamp technique showed that antigliomatin delayed rectifier potassium channels of C6 glioma cells.Antigliomatin inhibited tumor growth,which could potentially involve potassium channels of tumor cells.

  10. New similarity search based glioma grading

    Energy Technology Data Exchange (ETDEWEB)

    Haegler, Katrin; Brueckmann, Hartmut; Linn, Jennifer [Ludwig-Maximilians-University of Munich, Department of Neuroradiology, Munich (Germany); Wiesmann, Martin; Freiherr, Jessica [RWTH Aachen University, Department of Neuroradiology, Aachen (Germany); Boehm, Christian [Ludwig-Maximilians-University of Munich, Department of Computer Science, Munich (Germany); Schnell, Oliver; Tonn, Joerg-Christian [Ludwig-Maximilians-University of Munich, Department of Neurosurgery, Munich (Germany)

    2012-08-15

    MR-based differentiation between low- and high-grade gliomas is predominately based on contrast-enhanced T1-weighted images (CE-T1w). However, functional MR sequences as perfusion- and diffusion-weighted sequences can provide additional information on tumor grade. Here, we tested the potential of a recently developed similarity search based method that integrates information of CE-T1w and perfusion maps for non-invasive MR-based glioma grading. We prospectively included 37 untreated glioma patients (23 grade I/II, 14 grade III gliomas), in whom 3T MRI with FLAIR, pre- and post-contrast T1-weighted, and perfusion sequences was performed. Cerebral blood volume, cerebral blood flow, and mean transit time maps as well as CE-T1w images were used as input for the similarity search. Data sets were preprocessed and converted to four-dimensional Gaussian Mixture Models that considered correlations between the different MR sequences. For each patient, a so-called tumor feature vector (= probability-based classifier) was defined and used for grading. Biopsy was used as gold standard, and similarity based grading was compared to grading solely based on CE-T1w. Accuracy, sensitivity, and specificity of pure CE-T1w based glioma grading were 64.9%, 78.6%, and 56.5%, respectively. Similarity search based tumor grading allowed differentiation between low-grade (I or II) and high-grade (III) gliomas with an accuracy, sensitivity, and specificity of 83.8%, 78.6%, and 87.0%. Our findings indicate that integration of perfusion parameters and CE-T1w information in a semi-automatic similarity search based analysis improves the potential of MR-based glioma grading compared to CE-T1w data alone. (orig.)

  11. Immunoglobulin genes implicated in glioma risk.

    Science.gov (United States)

    Pandey, Janardan P; Kaur, Navtej; Costa, Sandra; Amorim, Julia; Nabico, Rui; Linhares, Paulo; Vaz, Rui; Viana-Pereira, Marta; Reis, Rui M

    2014-01-01

    Both genetic and environmental factors are thought to be causal in gliomagenesis. Several genes have been implicated in glioma development, but the putative role of a major immunity-related gene complex member, immunoglobulin heavy chain γ (IGHG) has not been evaluated. Prior observations that IGHG-encoded γ marker (GM) allotypes exhibit differential sensitivity to an immunoevasion strategy of cytomegalovirus, a pathogen implicated as a promoter of gliomagenesis, has lead us to hypothesize that these determinants are risk factors for glioma. To test this hypothesis, we genotyped the IGHG locus comprising the GM alleles, specifically GM alleles 3 and 17, of 120 glioma patients and 133 controls via TaqMan® genotyping assay. To assess the associations between GM genotypes and the risk of glioma, we applied an unconditional multivariate logistic regression analysis adjusted for potential confounding variables. In comparison to subjects who were homozygous for the GM 17 allele, the GM 3 homozygotes were over twice as likely, and the GM 3/17 heterozygotes were over three times as likely, to develop glioma. Similar results were achieved when analyzed by combining the data corresponding to alleles GM 3 and GM 3/17 in a dominant model. The GM 3/17 genotype and the combination of GM 3 and GM 3/17 were found to be further associated with over 3 times increased risk for high-grade astrocytoma (grades III-IV). Allele frequency analyses also showed an increased risk for gliomas and high-grade astrocytoma in association with GM 3. Our findings support the premise that the GM 3 allele may present risk for the development of glioma, possibly by modulating immunity to cytomegalovirus.

  12. A role for ion channels in perivascular glioma invasion.

    Science.gov (United States)

    Thompson, Emily G; Sontheimer, Harald

    2016-10-01

    Malignant gliomas are devastating tumors, frequently killing those diagnosed in little over a year. The profuse infiltration of glioma cells into healthy tissue surrounding the main tumor mass is one of the major obstacles limiting the improvement of patient survival. Migration along the abluminal side of blood vessels is one of the salient features of glioma cell invasion. Invading glioma cells are attracted to the vascular network, in part by the neuropeptide bradykinin, where glioma cells actively modify the gliovascular interface and undergo volumetric alterations to navigate the confined space. Critical to these volume modifications is a proposed hydrodynamic model that involves the flux of ions in and out of the cell, followed by osmotically obligated water. Ion and water channels expressed by the glioma cell are essential in this model of invasion and make opportune therapeutic targets. Lastly, there is growing evidence that vascular-associated glioma cells are able to control the vascular tone, presumably to free up space for invasion and growth. The unique mechanisms that enable perivascular glioma invasion may offer critical targets for therapeutic intervention in this devastating disease. Indeed, a chloride channel-blocking peptide has already been successfully tested in human clinical trials.

  13. Dynamic contrast enhanced MRI parameters and tumor cellularity in a rat model of cerebral glioma at 7T

    Science.gov (United States)

    Aryal, Madhava Prasad

    This dissertation mainly focuses on establishing and evaluating a stable and reproducible procedure for assessing tumor microvasculature by measuring the tissue parameters: plasma volume (vp), forward transfer constant (Ktrans), interstitial volume (ve) and distribution volume (VD), utilizing T1-weighted dynamic contrast enhanced MRI (DCE-MRI) and examining their relationship with a histo measure, cell counting. In the first part of the work, two T1-weighted DCE-MRI studies at 24 hrs time interval, using a dual-echo gradient-echo pulse sequence, were performed in 18 athymic rats implanted with U251 cerebral glioma. Using the "standard," or "consensus" model, and a separate Logan graphical analysis, T1-weighted images before, during and after the injection of a gadolinium contrast agent were used to estimate the tissue parameters mentioned above. After MRI study rats were sacrificed, and sectioned brain tissues were stained with Hematoxylin and Eosin for cell counting. Measurements in a region where a model selection process demonstrates that it can be reliably shown that contrast agent leaks from the capillary into the interstitial space quickly enough, and a concentration sufficient to measure its back flux to the vasculature, especially for Ktrans and ve, showed a remarkable stability. The combined mean parameter values in this region were: vp = (0.79+/-0.36)%, Ktrans = (2.23+/-0.71) x10-2 min -1, ve = (6.99+/-2.14)%, and VD = (7.57+/-2.32)%. In the second part of this work, the Logan graphical approach, after establishing its stability in an untreated control group, was applied to investigate a cohort of animals in which a therapeutic dose of 20 Gy radiation had been administered. In this cohort, tissue normalization appeared to be the most effective at 8 h after irradiation; this implies that the 8 hrs post-treatment time might be an ideal combination time for optimized therapeutic outcome in combined modalities. The relationship between non-invasive DCE

  14. Local delivery of rapamycin: a toxicity and efficacy study in an experimental malignant glioma model in rats.

    Science.gov (United States)

    Tyler, Betty; Wadsworth, Scott; Recinos, Violette; Mehta, Vivek; Vellimana, Ananth; Li, Khan; Rosenblatt, Joel; Do, Hiep; Gallia, Gary L; Siu, I-Mei; Wicks, Robert T; Rudek, Michelle A; Zhao, Ming; Brem, Henry

    2011-07-01

    Rapamycin, an anti-proliferative agent, is effective in the treatment of renal cell carcinoma and recurrent breast cancers. We proposed that this potent mammalian target of rapamycin inhibitor may be useful for the treatment of gliomas as well. We examined the cytotoxicity of rapamycin against a rodent glioma cell line, determined the toxicity of rapamycin when delivered intracranially, and investigated the efficacy of local delivery of rapamycin for the treatment of experimental malignant glioma in vivo. We also examined the dose-dependent efficacy of rapamycin and the effect when locally delivered rapamycin was combined with radiation therapy. Rapamycin was cytotoxic to 9L cells, causing 34% growth inhibition at a concentration of 0.01 µg/mL. No in vivo toxicity was observed when rapamycin was incorporated into biodegradable caprolactone-glycolide (35:65) polymer beads at 0.3%, 3%, and 30% loading doses and implanted intracranially. Three separate efficacy studies were performed to test the reproducibility of the effect of the rapamycin beads as well as the validity of this treatment approach. Animals treated with the highest dose of rapamycin beads tested (30%) consistently demonstrated significantly longer survival durations than the control and placebo groups. All dose-escalating rapamycin bead treatment groups (0.3%, 3% and 30%), treated both concurrently with tumor and in a delayed manner after tumor placement, experienced a significant increase in survival, compared with controls. Radiation therapy in addition to the simultaneous treatment with 30% rapamycin beads led to significantly longer survival duration than either therapy alone. These results suggest that the local delivery of rapamycin for the treatment of gliomas should be further investigated.

  15. Temozolomide in malignant glioma

    OpenAIRE

    Gregor Dresemann

    2010-01-01

    Gregor DresemannCenter for Neurooncology at Aerztehaus Velen, Velen, GermanyAbstract: Glioblastoma multiforme WHO grade IV (GBM) is the most aggressive ­malignant glioma and the most frequent primary tumor of the central nervous system. The median ­survival of newly diagnosed GBM patients was between 9 to 12 months prior to treatment with ­temozolomide being introduced. Primary resection that is as complete as possible is recommended for malignant glioma. Conventional ...

  16. Genetic Alterations in Glioma

    Energy Technology Data Exchange (ETDEWEB)

    Bralten, Linda B. C.; French, Pim J., E-mail: p.french@erasmusmc.nl [Department of Neurology, Erasmus University Medical Center, Erasmus University Rotterdam, Dr Molewaterplein 50, 3000 CA, Rotterdam (Netherlands)

    2011-03-07

    Gliomas are the most common type of primary brain tumor and have a dismal prognosis. Understanding the genetic alterations that drive glioma formation and progression may help improve patient prognosis by identification of novel treatment targets. Recently, two major studies have performed in-depth mutation analysis of glioblastomas (the most common and aggressive subtype of glioma). This systematic approach revealed three major pathways that are affected in glioblastomas: The receptor tyrosine kinase signaling pathway, the TP53 pathway and the pRB pathway. Apart from frequent mutations in the IDH1/2 gene, much less is known about the causal genetic changes of grade II and III (anaplastic) gliomas. Exceptions include TP53 mutations and fusion genes involving the BRAF gene in astrocytic and pilocytic glioma subtypes, respectively. In this review, we provide an update on all common events involved in the initiation and/or progression across the different subtypes of glioma and provide future directions for research into the genetic changes.

  17. Boldine: a potential new antiproliferative drug against glioma cell lines.

    Science.gov (United States)

    Gerhardt, Daniéli; Horn, Ana Paula; Gaelzer, Mariana Maier; Frozza, Rudimar Luiz; Delgado-Cañedo, Andrés; Pelegrini, Alessandra Luiza; Henriques, Amélia T; Lenz, Guido; Salbego, Christianne

    2009-12-01

    Malignant gliomas are the most common and devastating primary tumors of the central nervous system. Currently no efficient treatment is available. This study evaluated the effect and underlying mechanisms of boldine, an aporphine alkaloid of Peumus boldus, on glioma proliferation and cell death. Boldine decreased the cell number of U138-MG, U87-MG and C6 glioma lines at concentrations of 80, 250 and 500 muM. We observed that cell death caused by boldine was cell-type specific and dose-dependent. Exposure to boldine for 24 h did not activate key mediators of apoptosis. However, it induced alterations in the cell cycle suggesting a G(2)/M arrest in U138-MG cells. Boldine had no toxic effect on non-tumor cells when used at the same concentrations as those used on tumor cells. Based on these results, we speculate that boldine may be a promising compound for evaluation as an anti-cancer agent.

  18. Aptamer-functionalized PEG-PLGA nanoparticles for enhanced anti-glioma drug delivery.

    Science.gov (United States)

    Guo, Jianwei; Gao, Xiaoling; Su, Lina; Xia, Huimin; Gu, Guangzhi; Pang, Zhiqing; Jiang, Xinguo; Yao, Lei; Chen, Jun; Chen, Hongzhuan

    2011-11-01

    Targeted delivery of therapeutic nanoparticles in a disease-specific manner represents a potentially powerful technology especially when treating infiltrative brain tumors such as gliomas. We developed a nanoparticulate drug delivery system decorated with AS1411 (Ap), a DNA aptamer specifically binding to nucleolin which was highly expressed in the plasma membrane of both cancer cells and endothelial cells in angiogenic blood vessels, as the targeting ligand to facilitate anti-glioma delivery of paclitaxel (PTX). Ap was conjugated to the surface of PEG-PLGA nanoparticles (NP) via an EDC/NHS technique. With the conjugation confirmed by Urea PAGE and XPS, the resulting Ap-PTX-NP was uniformly round with particle size at 156.0 ± 54.8 nm and zeta potential at -32.93 ± 3.1 mV. Ap-nucleolin interaction significantly enhanced cellular association of nanoparticles in C6 glioma cells, and increased the cytotoxicity of its payload. Prolonged circulation and enhanced PTX accumulation at the tumor site was achieved for Ap-PTX-NP, which eventually obtained significantly higher tumor inhibition on mice bearing C6 glioma xenografts and prolonged animal survival on rats bearing intracranial C6 gliomas when compared with PTX-NP and Taxol(®). The results of this contribution demonstrated the potential utility of AS1411-functionalized nanoparticles for a therapeutic application in the treatment of gliomas.

  19. Presence of insulin receptors in cultured glial C6 cells. Regulation by butyrate.

    Science.gov (United States)

    Montiel, F; Ortiz-Caro, J; Villa, A; Pascual, A; Aranda, A

    1989-01-01

    The presence of insulin receptor and its regulation by butyrate and other short-chain fatty acids was studied in C6 cells, a rat glioma cell line. Intact C6 cells bind 125I-insulin in a rapid, reversible and specific manner. Scatchard analysis of the binding data gives typical curvilinear plots with apparent affinities of approx. 6 nM and 70 nM for the low-affinity (approx. 90% of total) and high-affinity (approx. 10% of total) sites respectively. Incubation with butyrate results in a time- and dose-dependent decrease of insulin binding to C6 cells. A maximal effect was found with 2 mM-butyrate that decreased the receptor by 40-70% after 48 h. Butyrate decreased numbers of receptors of both classes, but did not significantly alter receptor affinity. Other short-chain fatty acids, as well as keto acids, had a similar effect, but with a lower potency. Cycloheximide caused an accumulation of insulin receptors at the cell surface, since insulin binding increased and receptor affinity did not change after incubation with the inhibitor. Simultaneous addition of butyrate and cycloheximide abolished the loss of receptors produced by the fatty acid. In cells preincubated with butyrate, cycloheximide also produced a large increase in receptor numbers, showing that in the absence of new receptor synthesis a large pool of receptors re-appears at the surface of butyrate-treated cells. PMID:2930502

  20. C6 plate puncture testing report.

    Energy Technology Data Exchange (ETDEWEB)

    Vangoethem, Douglas J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cordova, Theresa Elena [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Reu, Phillip L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2013-04-01

    There are numerous scenarios where critical systems could be subject to penetration by projectiles or fixed objects (e.g., collision, natural disaster, act of terrorism, etc.). It is desired to use computational models to examine these scenarios and make risk-informed decisions; however, modeling of material failure is an active area of research, and new models must be validated with experimental data. The purpose of this report is to document the experimental work performed from FY07 through FY08 on the Campaign Six Plate Puncture project. The goal of this project was to acquire experimental data on the puncture and penetration of metal plates for use in model validation. Of particular interest is the PLH failure model also known as the multilinear line segment model. A significant amount of data that will be useful for the verification and validation of computational models of ductile failure were collected during this project were collected and documented herein; however, much more work remains to be performed, collecting additional experimental data that will further the task of model verification.

  1. Comparison of CT and MRI brain tumor imaging using a canine glioma model.

    Science.gov (United States)

    Whelan, H T; Clanton, J A; Wilson, R E; Tulipan, N B

    1988-01-01

    A canine gliosarcoma model was used to study the effectiveness of magnetic resonance imaging (MRI) with gadolinium contrast enhancement in defining the histologic margins of brain tumors. The effectiveness of this technique was compared to conventional computed tomography (CT) using iodinated contrast enhancement. Cultured canine gliosarcoma cells were injected into the left hemisphere of adult mongrel dogs. The dogs developed brain tumors and progressive clinical signs. Serial MRI with and without gadolinium diethylene triamine penta-acetic acid was compared to serial CT with and without sodium iothalamate obtained on the same days. After the final scans, animals were sacrificed; the brains were removed and processed for routine histopathologic study. All tumors were visualized with contrast-enhanced MRI which proved most sensitive. Gadolinium di-ethylene triamine penta-acetic acid caused bright enhancement of tumors in a distribution that consistently corresponded to areas of pathologically proved tumor infiltration. Gross and microscopic autopsy findings correlated better with MRI than with CT which tended to produce poorer resolution and underrepresent the size of viable tumor. Gadolinium-enhanced MRI is more accurate than unenhanced MRI, unenhanced CT, or enhanced CT in defining the histologic margins of tumors.

  2. Human autologous in vitro models of glioma immunogene therapy using B7-2, GM-CSF, and IL12

    Energy Technology Data Exchange (ETDEWEB)

    Parney, I.F.; Farr-Jones, M.A. [Univ. of Alberta, Div. of Neurosurgery, Edmonton, Alberta (Canada); Kane, K.; Chang, L.-J. [Univ. of Alberta, Dept. of Surgery and Dept. of Medical Microbiology and Immunology, Edmonton, Alberta (Canada); Petruk, K.C. [Univ. of Alberta, Div. of Neurosurgery, Edmonton, Alberta (Canada)

    2002-08-01

    Cancer immunogene therapy is based on vaccination with radiated, autologous tumor cells transduced with immunostimulatory genes. To help determine an optimal glioma immunogene therapy strategy, we stimulated lymphocytes with autologous human glioma cells transduced with B7-2 (CD86), granulocyte-macrophage colony-stimulating factor (GM-CSF), and/or interleukin-12 (IL12). A human glioma-derived cell culture (Ed147.BT) was transduced with B7-2, GM-CSF, and/or IL12 using retroviral vectors. Autologous peripheral blood mononuclear cells (PBMC) were co-cultured with irradiated gene-transduced tumor alone or a combination of radiated wild type and gene-transduced cells. Peripheral blood mononuclear cells proliferation was determined by serial cell counts. Peripheral blood mononuclear cells phenotype was assessed by flow cytometry for CD4, CD8, and CD16. Anti-tumor cytotoxicity was determined by chromium-51 ({sup 51}Cr) release assay. Peripheral blood mononuclear cells cell numbers all decreased during primary stimulation but tumor cells expressing B7-2 or GM-CSF consistently caused secondary proliferation. Tumors expressing B7-2 and GM-CSF or B7-2,GM-CSF,and IL12 consistently increased PBMC CD8+ (cytotoxic T) and CD16+ (natural killer) percentages. Interestingly, anti-tumor cytotoxicity only exceeded that of PBMC stimulated with wild type tumor alone when peripheral blood mononuclear cells were stimulated with both wild type tumor and B7-2/GM-CSF- (but not IL12) transduced cells. PBMC proliferation and phenotype is altered as expected by exposure to immunostimulatory gene-transduced tumor. However, transduced tumor cells alone do not stimulate greater anti-tumor cytotoxicity than wild type tumor. Only B7-2/GM-CSF-transduced cells combined with wild type produced increased cytotoxicity. This may reflect selection of turnor subclones with limited antigenic spectra during retrovirus-mediated gene transfer. (author)

  3. 26 CFR 1.414(c)-6 - Effective date.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Effective date. 1.414(c)-6 Section 1.414(c)-6 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.414(c)-6 Effective date. (a)...

  4. Expression and function of DMT1 without IRE in C6 cells mediated by recombinant adenovirus

    Institute of Scientific and Technical Information of China (English)

    Xixun DU; Huamin XU; Hong JIANG; Jun WANG; Lei WANG; Junxia XIE

    2009-01-01

    Divalent metal transporter 1 (DMT1) is a ferrous iron import protein. The improper expression of DMT1 is involved in neurodegenerative diseases. In the present study, we constructed a recombinant adenovirus containing the gene of DMT1 without the iron response element (DMT1-IRE) and investigated its expression and function in the C6 glioma cell line. The DMTI-IRE gene, obtained by RT-PCR, was cloned into the shuttle plasmid-ing pAdTrack-CMV containing green fluorescent protein (GFP) reporter gene. Linearized plasmid pAdTrack-CMV-DMTI-IRE was subsequently co-transformed into Escher-iehia coli (E. coli) BJ5183 cells along with an adenoviral backbone plasmid pAdEasy-1 after digestion with Pme I. Pac I-digested pAdEasy 1-DMT 1-IRE was then transfected into El-transformed human embryonic kidney cells (HEK293 cells), in which recombinant adenoviruses were generated within 7 to 10 days. The results demon-strated that we obtained the DMTI-IRE gene. pAdEasyl-DMT1-IRE yielded a large fragment, plus a smaller fragment of 4.5kb after digestion with Pac I. PCR confirmed pAdEasy1-DMT1-IRE contained gene DMT1-IRE, indicating the successful construction of recombi-nant adenovirus plasmid containing DMT1-IRE. GFP fluorescence further confirmed the generation of recombi-nant AdDMTI-IRE adenovirus. AdDMTI-IRE could efficiently infect C6 glioma cells. And cell viability decreased in AdDMT1-IRE infected cells after iron overload compared to the control. These results suggest that the over expressed DMT1-IRE can aggravate the iron induced cell death due to its iron influx function.

  5. Resistance to Oncolytic Myxoma Virus Therapy in Nf1−/−/Trp53−/− Syngeneic Mouse Glioma Models Is Independent of Anti-Viral Type-I Interferon

    Science.gov (United States)

    Zemp, Franz J.; McKenzie, Brienne A.; Lun, Xueqing; Maxwell, Lori; Reilly, Karlyne M.; McFadden, Grant; Yong, V. Wee; Forsyth, Peter A.

    2013-01-01

    Despite promising preclinical studies, oncolytic viral therapy for malignant gliomas has resulted in variable, but underwhelming results in clinical evaluations. Of concern are the low levels of tumour infection and viral replication within the tumour. This discrepancy between the laboratory and the clinic could result from the disparity of xenograft versus syngeneic models in determining in vivo viral infection, replication and treatment efficacy. Here we describe a panel of primary mouse glioma lines derived from Nf1+/−Trp53+/− mice in the C57Bl/6J background for use in the preclinical testing of the oncolytic virus Myxoma (MYXV). These lines show a range of susceptibility to MYXV replication in vitro, but all succumb to viral-mediated cell death. Two of these lines orthotopically grafted produced aggressive gliomas. Intracranial injection of MYXV failed to result in sustained viral replication or treatment efficacy, with minimal tumour infection that was completely resolved by 7 days post-infection. We hypothesized that the stromal production of Type-I interferons (IFNα/β) could explain the resistance seen in these models; however, we found that neither the cell lines in vitro nor the tumours in vivo produce any IFNα/β in response to MYXV infection. To confirm IFNα/β did not play a role in this resistance, we ablated the ability of tumours to respond to IFNα/β via IRF9 knockdown, and generated identical results. Our studies demonstrate that these syngeneic cell lines are relevant preclinical models for testing experimental glioma treatments, and show that IFNα/β is not responsible for the MYXV treatment resistance seen in syngeneic glioma models. PMID:23762429

  6. Ionizing radiation improves glioma-specific targeting of superparamagnetic iron oxide nanoparticles conjugated with cmHsp70.1 monoclonal antibodies (SPION-cmHsp70.1)

    Science.gov (United States)

    Shevtsov, Maxim A.; Nikolaev, Boris P.; Ryzhov, Vyacheslav A.; Yakovleva, Ludmila Y.; Marchenko, Yaroslav Y.; Parr, Marina A.; Rolich, Valerij I.; Mikhrina, Anastasiya L.; Dobrodumov, Anatolii V.; Pitkin, Emil; Multhoff, Gabriele

    2015-12-01

    The stress-inducible 72 kDa heat shock protein Hsp70 is known to be expressed on the membrane of highly aggressive tumor cells including high-grade gliomas, but not on the corresponding normal cells. Membrane Hsp70 (mHsp70) is rapidly internalized into tumor cells and thus targeting of mHsp70 might provide a promising strategy for theranostics. Superparamagnetic iron oxide nanoparticles (SPIONs) are contrast negative agents that are used for the detection of tumors with MRI. Herein, we conjugated the Hsp70-specific antibody (cmHsp70.1) which is known to recognize mHsp70 to superparamagnetic iron nanoparticles to assess tumor-specific targeting before and after ionizing irradiation. In vitro experiments demonstrated the selectivity of SPION-cmHsp70.1 conjugates to free and mHsp70 in different tumor cell types (C6 glioblastoma, K562 leukemia, HeLa cervix carcinoma) in a dose-dependent manner. High-resolution MRI (11 T) on T2-weighted images showed the retention of the conjugates in the C6 glioma model. Accumulation of SPION-cmHsp70.1 nanoparticles in the glioma resulted in a nearly 2-fold drop of values in comparison to non-conjugated SPIONs. Biodistribution analysis using NLR-M2 measurements showed a 7-fold increase in the tumor-to-background (normal brain) uptake ratio of SPION-cmHsp70.1 conjugates in glioma-bearing rats in comparison to SPIONs. This accumulation within Hsp70-positive glioma was further enhanced after a single dose (10 Gy) of ionizing radiation. Elevated accumulation of the magnetic conjugates in the tumor due to radiosensitization proves the combination of radiotherapy and application of Hsp70-targeted agents in brain tumors.The stress-inducible 72 kDa heat shock protein Hsp70 is known to be expressed on the membrane of highly aggressive tumor cells including high-grade gliomas, but not on the corresponding normal cells. Membrane Hsp70 (mHsp70) is rapidly internalized into tumor cells and thus targeting of mHsp70 might provide a promising strategy

  7. Silver nanoparticles outperform gold nanoparticles in radiosensitizing U251 cells in vitro and in an intracranial mouse model of glioma

    Science.gov (United States)

    Liu, Peidang; Jin, Haizhen; Guo, Zhirui; Ma, Jun; Zhao, Jing; Li, Dongdong; Wu, Hao; Gu, Ning

    2016-01-01

    Radiotherapy performs an important function in the treatment of cancer, but resistance of tumor cells to radiation still remains a serious concern. More research on more effective radiosensitizers is urgently needed to overcome such resistance and thereby improve the treatment outcome. The goal of this study was to evaluate and compare the radiosensitizing efficacies of gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) on glioma at clinically relevant megavoltage energies. Both AuNPs and AgNPs potentiated the in vitro and in vivo antiglioma effects of radiation. AgNPs showed more powerful radiosensitizing ability than AuNPs at the same mass and molar concentrations, leading to a higher rate of apoptotic cell death. Furthermore, the combination of AgNPs with radiation significantly increased the levels of autophagy as compared with AuNPs plus radiation. These findings suggest the potential application of AgNPs as a highly effective nano-radiosensitizer for the treatment of glioma. PMID:27757033

  8. Specific targeting of gliomas with multifunctional superparamagnetic iron oxide nanoparticle optical and magnetic resonance imaging contrast agents

    Institute of Scientific and Technical Information of China (English)

    Xiang-xi MENG; Jia-qi WAN; Meng JING; Shi-guang ZHAO; Wei CAI; En-zhong LIU

    2007-01-01

    Aim: To determine whether glioma cells can be specifically and efficiently tar- geted by superparamagnetic iron oxide nanoparticle (SPIO)-fluorescein isothiocyanate (FITC)-chlorotoxin (SPIOFC) that is detectable by magnetic reso- nance imaging (MRI) and optical imaging. Methods: SPIOFC was synthesized by conjugating SPIO with FITC and chlorotoxin. Glioma cells (human U251-MG and rat C6) were cultured with SPIOFC and SPIOF (SPIO-FITC), respectively. Neural cells were treated with SPIOFC as the control for SPIOFC-targeted glioma cells. The internalization of SPIOFC by glioma cells was assessed by MRI and was quantified using inductively-coupled plasma emission spectroscopy. The optical imaging ability of SPIOFC was evaluated by confocal laser scanning microscopy. Results: Iron per cell of U251 (72.5±1.8 pg) and C6 (74.9±2.2 pg) cells cultured with SPIOFC were significantly more than those of U251 (6.6±1.0 pg) and C6 (7.1±0.8 pg) cells incubated with SPIOF. The T2 signal intensity of U251 and C6 cells cultured with SPIOFC (233.6±25.9 and 211.4±17.2, respectively) were substantially lower than those of U251 and C6 cells incubated with SPIOF (2275.3±268.6 and 2342.7±222.4, respectively). Moreover, there were significant differences in iron per cell and T2 signal intensity between SPIOFC-treated neural cells (1.3±0.3; 2533.6±199.2) and SPIOFC-treated glioma cells. SPIOFC internalized by glioma cells exhibited green fluorescence by confocal laser scanning microscopy. Conclusion: SPIOFC is suitable for the specific and efficient targeting of glioma cells. MRI and optical imaging in conjunction with SPIOFC can differentiate glioma cells from normal brain tissue cells.

  9. Immunohistochemical evaluation of tissue factor, fibrin/fibrinogen and D-dimers in canine gliomas.

    Science.gov (United States)

    de la Fuente, Cristian; Pumarola, Martí; Blasco, Ester; Fernández, Francisco; Viu, Judit; Añor, Sònia

    2014-06-01

    In human gliomas, tissue factor (TF) is overexpressed, associated with the grade of malignancy and influences tumour biology. Intra-tumoural fibrin/fibrinogen deposition and activation of the fibrinolytic system also play a role in tumour cell proliferation and angiogenesis. The first aim of the present study was to investigate TF expression and the presence of fibrin/fibrinogen and D-dimers in canine glioma biopsies, graded according to the World Health Organization (WHO) classification of tumours of the central nervous system. The second aim was to investigate the occurrence of intravascular thrombosis (IVT) in canine gliomas, as a potential histological marker of glioma type or grade of malignancy. An immunohistochemical study using antibodies against TF, fibrin/fibrinogen and D-dimers was performed with 24 glioma samples, including 15 oligodendrogliomas, 6 astrocytomas and 3 mixed gliomas. Immunohistochemical data were statistically analysed to determine whether there was any relationship between glioma type and grade of malignancy. All gliomas were moderate to strongly positive for TF and the staining score was significantly higher (P = 0.04) in high-grade (III or IV) than in low-grade (II) gliomas. Intra-tumoural fibrin/fibrinogen deposition was detected in all tumour biopsies assessed, and D-dimers were detected in 17/24 gliomas. IVT was a frequent finding, but was not linked to a specific glioma type or malignancy grade. TF expression, fibrin/fibrinogen deposition, extravascular fibrinolytic system activation and IVT occur in canine gliomas. Canine glioma might be a suitable model for studying coagulation and fibrinolysis as potential therapeutic targets for human gliomas.

  10. TH-E-BRF-05: Comparison of Survival-Time Prediction Models After Radiotherapy for High-Grade Glioma Patients Based On Clinical and DVH Features

    Energy Technology Data Exchange (ETDEWEB)

    Magome, T; Haga, A; Igaki, H; Sekiya, N; Masutani, Y; Sakumi, A; Mukasa, A; Nakagawa, K [The University of Tokyo Hospital, Tokyo, JP (Japan)

    2014-06-15

    Purpose: Although many outcome prediction models based on dose-volume information have been proposed, it is well known that the prognosis may be affected also by multiple clinical factors. The purpose of this study is to predict the survival time after radiotherapy for high-grade glioma patients based on features including clinical and dose-volume histogram (DVH) information. Methods: A total of 35 patients with high-grade glioma (oligodendroglioma: 2, anaplastic astrocytoma: 3, glioblastoma: 30) were selected in this study. All patients were treated with prescribed dose of 30–80 Gy after surgical resection or biopsy from 2006 to 2013 at The University of Tokyo Hospital. All cases were randomly separated into training dataset (30 cases) and test dataset (5 cases). The survival time after radiotherapy was predicted based on a multiple linear regression analysis and artificial neural network (ANN) by using 204 candidate features. The candidate features included the 12 clinical features (tumor location, extent of surgical resection, treatment duration of radiotherapy, etc.), and the 192 DVH features (maximum dose, minimum dose, D95, V60, etc.). The effective features for the prediction were selected according to a step-wise method by using 30 training cases. The prediction accuracy was evaluated by a coefficient of determination (R{sup 2}) between the predicted and actual survival time for the training and test dataset. Results: In the multiple regression analysis, the value of R{sup 2} between the predicted and actual survival time was 0.460 for the training dataset and 0.375 for the test dataset. On the other hand, in the ANN analysis, the value of R{sup 2} was 0.806 for the training dataset and 0.811 for the test dataset. Conclusion: Although a large number of patients would be needed for more accurate and robust prediction, our preliminary Result showed the potential to predict the outcome in the patients with high-grade glioma. This work was partly supported by

  11. Noscapine inhibits tumor growth in TMZ-resistant gliomas.

    Science.gov (United States)

    Jhaveri, Niyati; Cho, Heeyeon; Torres, Shering; Wang, Weijun; Schönthal, Axel H; Petasis, Nicos A; Louie, Stan G; Hofman, Florence M; Chen, Thomas C

    2011-12-22

    Noscapine, a common oral antitussive agent, has been shown to have potent antitumor activity in a variety of cancers. Treatment of glioblastoma multiforme (GBM) with temozolomide (TMZ), its current standard of care, is problematic because the tumor generally recurs and is then resistant to this drug. We therefore investigated the effects of noscapine on human TMZ-resistant GBM tumors. We found that noscapine significantly decreased TMZ-resistant glioma cell growth and invasion. Using the intracranial xenograft model, we showed that noscapine increased survival of animals with TMZ-resistant gliomas. Thus noscapine can provide an alternative therapeutic approach for the treatment of TMZ-resistant gliomas.

  12. Identification of molecular pathways facilitating glioma cell invasion in situ.

    Directory of Open Access Journals (Sweden)

    Ido Nevo

    Full Text Available Gliomas are mostly incurable secondary to their diffuse infiltrative nature. Thus, specific therapeutic targeting of invasive glioma cells is an attractive concept. As cells exit the tumor mass and infiltrate brain parenchyma, they closely interact with a changing micro-environmental landscape that sustains tumor cell invasion. In this study, we used a unique microarray profiling approach on a human glioma stem cell (GSC xenograft model to explore gene expression changes in situ in Invading Glioma Cells (IGCs compared to tumor core, as well as changes in host cells residing within the infiltrated microenvironment relative to the unaffected cortex. IGCs were found to have reduced expression of genes within the extracellular matrix compartment, and genes involved in cell adhesion, cell polarity and epithelial to mesenchymal transition (EMT processes. The infiltrated microenvironment showed activation of wound repair and tissue remodeling networks. We confirmed by protein analysis the downregulation of EMT and polarity related genes such as CD44 and PARD3 in IGCs, and EFNB3, a tissue-remodeling agent enriched at the infiltrated microenvironment. OLIG2, a proliferation regulator and glioma progenitor cell marker upregulated in IGCs was found to function in enhancing migration and stemness of GSCs. Overall, our results unveiled a more comprehensive picture of the complex and dynamic cell autonomous and tumor-host interactive pathways of glioma invasion than has been previously demonstrated. This suggests targeting of multiple pathways at the junction of invading tumor and microenvironment as a viable option for glioma therapy.

  13. Pharmacological doses of daily ascorbate protect tumours from radiation damage after a single dose of radiation in an intracranial mouse glioma model

    Directory of Open Access Journals (Sweden)

    Carole eGrasso

    2014-12-01

    Full Text Available Pharmacological ascorbate is currently used as an anti-cancer treatment, potentially in combination with radiation therapy, by integrative medicine practitioners. In the acidic, metal-rich tumour environment, ascorbate acts as a pro-oxidant, with a mode of action similar to that of ionising radiation; both treatments kill cells predominantly by free radical-mediated DNA damage. The brain tumour, glioblastoma multiforme (GBM, is very resistant to radiation; radiosensitising GBM cells will improve survival of GBM patients. Here we demonstrate that a single fraction (6 Gy of radiation combined with a one hour exposure to ascorbate (5 mM sensitised murine glioma GL261cells to radiation in survival and colony-forming assays in vitro. In addition, we report the effect of a single fraction (4.5 Gy of whole brain radiation combined with daily intra-peritoneal injections of ascorbate (1 mg/kg in an intra-cranial GL261 glioma mouse model. Tumour-bearing C57BL/6 mice were divided into four groups: one group received a single dose of 4.5 Gy to the brain eight days after tumour implantation, a second group received daily intra-peritoneal injections of ascorbate (day 8-45 after implantation, a third group received both treatments and a fourth control group received no treatment. While radiation delayed tumour progression, intra-peritoneal ascorbate alone had no effect on tumour progression. Tumour progression was faster in tumour-bearing mice treated with radiation and daily ascorbate than those treated with radiation alone. Histological analysis showed less necrosis in tumours treated with both radiation and ascorbate, consistent with a radio-protective effect of ascorbate in vivo. Discrepancies between our in vitro and in vivo results may be explained by differences in the tumour micro-environment which determines whether ascorbate remains outside the cell, acting as a pro-oxidant or whether it enters the cells and acts as an anti-oxidant.

  14. Pharmacological doses of daily ascorbate protect tumors from radiation damage after a single dose of radiation in an intracranial mouse glioma model.

    Science.gov (United States)

    Grasso, Carole; Fabre, Marie-Sophie; Collis, Sarah V; Castro, M Leticia; Field, Cameron S; Schleich, Nanette; McConnell, Melanie J; Herst, Patries M

    2014-01-01

    Pharmacological ascorbate is currently used as an anti-cancer treatment, potentially in combination with radiation therapy, by integrative medicine practitioners. In the acidic, metal-rich tumor environment, ascorbate acts as a pro-oxidant, with a mode of action similar to that of ionizing radiation; both treatments kill cells predominantly by free radical-mediated DNA damage. The brain tumor, glioblastoma multiforme (GBM), is very resistant to radiation; radiosensitizing GBM cells will improve survival of GBM patients. Here, we demonstrate that a single fraction (6 Gy) of radiation combined with a 1 h exposure to ascorbate (5 mM) sensitized murine glioma GL261 cells to radiation in survival and colony-forming assays in vitro. In addition, we report the effect of a single fraction (4.5 Gy) of whole brain radiation combined with daily intraperitoneal injections of ascorbate (1 mg/kg) in an intracranial GL261 glioma mouse model. Tumor-bearing C57BL/6 mice were divided into four groups: one group received a single dose of 4.5 Gy to the brain 8 days after tumor implantation, a second group received daily intraperitoneal injections of ascorbate (day 8-45) after implantation, a third group received both treatments and a fourth control group received no treatment. While radiation delayed tumor progression, intraperitoneal ascorbate alone had no effect on tumor progression. Tumor progression was faster in tumor-bearing mice treated with radiation and daily ascorbate than in those treated with radiation alone. Histological analysis showed less necrosis in tumors treated with both radiation and ascorbate, consistent with a radio-protective effect of ascorbate in vivo. Discrepancies between our in vitro and in vivo results may be explained by differences in the tumor microenvironment, which determines whether ascorbate remains outside the cell, acting as a pro-oxidant, or whether it enters the cells and acts as an anti-oxidant.

  15. Isomerisation of c4-c6 aldoses with zeolites

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to isomerization of C4-C6 aldoses to their corresponding C4-C6 ketoses. In particular, the invention concerns isomerization of C4-C6 aldoses over solid zeolite catalysts free of any metals other than aluminum, in the presence of suitable solvent(s) at suitable elevated...... temperatures. C6 and C5 aldose sugars such as glucose and xylose, which are available in large amounts from biomass precursors, are isomerized to fructose and xylulose respectively, in a one or two-step process over inexpensive commercially available zeolite catalysts, containing aluminum as the only metal...

  16. Silver nanoparticles: a novel radiation sensitizer for glioma?

    Science.gov (United States)

    Liu, Peidang; Huang, Zhihai; Chen, Zhongwen; Xu, Ruizhi; Wu, Hao; Zang, Fengchao; Wang, Cailian; Gu, Ning

    2013-11-01

    Malignant gliomas are the most common primary intracranial tumors with a dismal prognosis. Previous investigations by our group demonstrated the radiosensitizing effect of silver nanoparticles (AgNPs) on glioma cells in vitro. The goal of the present study was to evaluate the efficacy of intratumoral administration of AgNPs in combination with a single dose of ionizing radiation at clinically relevant MV energies for the treatment of C6 glioma-bearing rats. AgNPs (10 or 20 μg/10 μl) were stereotactically administered on day 8 after tumor implantation. One day after AgNP injection, rats bearing glioma received 10 Gy radiation. The mean survival times were 100.5 and 98 days, the corresponding percent increase in life spans was 513.2% and 497.7%, and the cure rates were 41.7 and 38.5% at 200 days for the 10 and 20 μg AgNPs and radiation combination groups, respectively. In contrast, the mean survival times for irradiated controls, 10 and 20 μg AgNPs alone, and untreated controls were 24.5, 16.1, 19.4, and 16.4 days, respectively. Furthermore, a cooperative antiproliferative and proapoptotic effect was obtained when gliomas were treated with AgNPs followed by radiotherapy. Our results showed the therapeutic efficacy of AgNPs in combination with radiotherapy without apparent systemic toxicity, suggesting the clinical potential of AgNPs in improving the outcome of malignant glioma radiotherapy.Malignant gliomas are the most common primary intracranial tumors with a dismal prognosis. Previous investigations by our group demonstrated the radiosensitizing effect of silver nanoparticles (AgNPs) on glioma cells in vitro. The goal of the present study was to evaluate the efficacy of intratumoral administration of AgNPs in combination with a single dose of ionizing radiation at clinically relevant MV energies for the treatment of C6 glioma-bearing rats. AgNPs (10 or 20 μg/10 μl) were stereotactically administered on day 8 after tumor implantation. One day after Ag

  17. A synthetic dl-nordihydroguaiaretic acid (Nordy, inhibits angiogenesis, invasion and proliferation of glioma stem cells within a zebrafish xenotransplantation model.

    Directory of Open Access Journals (Sweden)

    Xiaojun Yang

    Full Text Available The zebrafish (Danio rerio and their transparent embryos represent a promising model system in cancer research. Compared with other vertebrate model systems, we had previously shown that the zebrafish model provides many advantages over mouse or chicken models to study tumor invasion, angiogenesis, and tumorigenesis. In this study, we systematically investigated the biological features of glioma stem cells (GSCs in a zebrafish model, such as tumor angiogenesis, invasion, and proliferation. We demonstrated that several verified anti-angiogenic agents inhibited angiogenesis that was induced by xenografted-GSCs. We next evaluated the effects of a synthetic dl-nordihydroguaiaretic acid compound (dl-NDGA or "Nordy", which revealed anti-tumor activity against human GSCs in vitro by establishing parameters through studying its ability to suppress angiogenesis, tumor invasion, and proliferation. Furthermore, our results indicated that Nordy might inhibit GSCs invasion and proliferation through regulation of the arachidonate 5-lipoxygenase (Alox-5 pathway. Moreover, the combination of Nordy and a VEGF inhibitor exhibited an enhanced ability to suppress angiogenesis that was induced by GSCs. By contrast, even following treatment with 50 µM Nordy, there was no discernible effect on zebrafish embryonic development. Together, these results suggested efficacy and safety of using Nordy in vivo, and further demonstrated that this model should be suitable for studying GSCs and anti-GSC drug evaluation.

  18. Alpinetin targets glioma stem cells by suppressing Notch pathway.

    Science.gov (United States)

    Wang, Jianpeng; Yan, Zhiyong; Liu, Xia; Che, Shusheng; Wang, Chao; Yao, Weicheng

    2016-07-01

    Glioma is among the most common human malignancies with poor prognosis. Glioma stem cells (GSCs) are the culprit of glioma, suggesting that GSCs are potential therapeutic targets. Notch signaling pathway plays a pivotal role for the function of GSCs, implying that suppression of Notch pathway may be an effective strategy for GSC-targeting therapy. In this study, we found that alpinetin, a natural compound, can suppress the proliferation and invasiveness of GSCs and induce apoptosis in GSCs. Immunoblot analysis and luciferase assay revealed that Notch signaling was suppressed by alpinetin. Furthermore, restoration of Notch signaling activity rescued the effect of alpinetin on GSC's function. The anti-tumor activity of alpinetin was further confirmed in an animal model. Collectively, targeting of GSC by alpinetin is an effective strategy for glioma therapy.

  19. Dynamic contrast-enhanced susceptibility-weighted perfusion MRI (DSC-MRI) in a glioma model of the rat brain using a conventional receive-only surface coil with a inner diameter of 47 mm at a clinical 1.5 T scanner.

    Science.gov (United States)

    Ulmer, Stephan; Reeh, Matthias; Krause, Joerg; Herdegen, Thomas; Heldt-Feindt, Janka; Jansen, Olav; Rohr, Axel

    2008-07-30

    Magnetic resonance (MR) imaging in animal models is usually performed in expensive dedicated small bore animal scanners of limited availability. In the present study a standard clinical 1.5 T MR scanner was used for morphometric and dynamic contrast-enhanced susceptibility-weighted MR imaging (DSC-MRI) of a glioma model of the rat brain. Ten male Wistar rats were examined with coronal T2-weighted, and T1-weighted images (matrix 128 x 128, FOV 64 mm) after implantation of an intracerebral tumor xenografts (C6) using a conventional surface coil. For DSC-MRI a T2*-weighted sequence (TR/TE=30/14 ms, matrix 64 x 64, FOV 90 mm; slice thickness of 1.5mm) was performed. Regions of interest were defined within the tumor and the non-affected contralateral hemisphere and the mean transit time (MTT) was determined. Tumor dimensions in MR predicted well its real size as proven by histology. The MTT of contrast agent passing through the brain was significantly decelerated in the tumor compared to the unaffected hemisphere (pscanners or dedicated custom-made coils.

  20. Human gliomas contain morphine

    DEFF Research Database (Denmark)

    Olsen, Peter; Rasmussen, Mads; Zhu, Wei

    2005-01-01

    morphine via high pressure liquid chromatography (HPLC). The HPLC peak corresponding to an authentic morphine standard had its morphine level determined via radioimmune assay. The identity of this material was established by Q-TOF-MS analysis. RESULTS: Each glioma exhibited an endogenous morphine presence....... Tumor extractions demonstrated a molecular mass of 286.14 da, identical to authentic morphine. Subsequent fragmentation analysis of this molecule revealed fragment masses of 129.01 da, 183.09 da and 201.07 da, corresponding to authentic morphine fragments. This material was not found in any......BACKGROUND: Morphine has been found in cancer cell lines originating from human and animal cells. Thus, it became important to demonstrate whether or not actual tumours contain this opiate alkaloid. MATERIAL/METHODS: Human glioma tissues were biochemically treated to isolate and separate endogenous...

  1. Gene Therapy for Gliomas

    OpenAIRE

    Nanda, Dharminderkoemar

    2008-01-01

    textabstractThe overall median survival in glioblastoma multiforme (GBM) patients is less than one year and fewer than 5% of patients survive more than 5 years. The current standard of care for GBM patients involves neurosurgical resection of the tumor followed by radiotherapy with concomitant and adjuvant temozolomide chemotherapy. After initial treatment, all malignant gliomas eventually recur, mostly within a 2-3 cm margin of the original tumor on CT/MRI. The poor prognosis warrants resear...

  2. Water-soluble L-cysteine-coated FePt nanoparticles as dual MRI/CT imaging contrast agent for glioma.

    Science.gov (United States)

    Liang, Shuyan; Zhou, Qing; Wang, Min; Zhu, Yanhong; Wu, Qingzhi; Yang, Xiangliang

    2015-01-01

    Nanoparticles (NPs) are advantageous for the delivery of diagnosis agents to brain tumors. In this study, we attempted to develop an L-cysteine coated FePt (FePt-Cys) NP as MRI/CT imaging contrast agent for the diagnosis of malignant gliomas. FePt-Cys NPs were synthesized through a co-reduction route, which was characterized by transmission electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light scattering. The MRI and CT imaging ability of FePt-Cys NPs was evaluated using different gliomas cells (C6, SGH44, U251) as the model. Furthermore, the biocompatibility of the as-synthesized FePt-Cys NPs was evaluated using three different cell lines (ECV304, L929, and HEK293) as the model. The results showed that FePt-Cys NPs displayed excellent biocompatibility and good MRI/CT imaging ability, thereby indicating promising potential as a dual MRI/CT contrast agent for the diagnosis of brain malignant gliomas.

  3. Enhancement in blood-tumor barrier permeability and delivery of liposomal doxorubicin using focused ultrasound and microbubbles: evaluation during tumor progression in a rat glioma model

    Science.gov (United States)

    Aryal, Muna; Park, Juyoung; Vykhodtseva, Natalia; Zhang, Yong-Zhi; McDannold, Nathan

    2015-03-01

    Effective drug delivery to brain tumors is often challenging because of the heterogeneous permeability of the ‘blood tumor barrier’ (BTB) along with other factors such as increased interstitial pressure and drug efflux pumps. Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as the blood-brain barrier in the surrounding tissue. In this study, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was used to characterize the FUS-induced permeability changes of the BTB in a rat glioma model at different times after implantation. 9L gliosarcoma cells were implanted in both hemispheres in male rats. At day 9, 14, or 17 days after implantation, FUS-induced BTB disruption using 690 kHz ultrasound and definity microbubbles was performed in one tumor in each animal. Before FUS, liposomal doxorubicin was administered at a dose of 5.67 mg kg-1. This chemotherapy agent was previously shown to improve survival in animal glioma models. The transfer coefficient Ktrans describing extravasation of the MRI contrast agent Gd-DTPA was measured via DCE-MRI before and after sonication. We found that tumor doxorubicin concentrations increased monotonically (823  ±  600, 1817  ±  732 and 2432  ±  448 ng g-1) in the control tumors at 9, 14 and 17 d. With FUS-induced BTB disruption, the doxorubicin concentrations were enhanced significantly (P tumors by a factor of two or more (2222  ±  784, 3687  ±  796 and 5658  ±  821 ng g-1) regardless of the stage of tumor growth. The transfer coefficient Ktrans was significantly (P tumors only at day 9 but not at day 14 or 17. These results suggest that FUS-induced enhancements in tumor drug delivery are relatively consistent over time, at least in this tumor model. These results are encouraging for the use of large drug carriers, as they suggest that even large/late-stage tumors can benefit from FUS-induced drug enhancement

  4. 替莫唑胺联合小剂量缓激肽对延长胶质瘤大鼠生存期的观察%Observe effects of Temozolomide combined with low dose Bradykinin in prolonging survival time of rat with glioma

    Institute of Scientific and Technical Information of China (English)

    于倩; 宋飞; 刘贺; 白莉娜

    2012-01-01

    Objective To investigate the effect of Temozolomide combined with low dose Bradykinin for glioma therapy. Methods To use the stereotactic method to establish the C6 glioma model rats,and lest the glioma growth by MRI. Observerd the survival condition of the models treated with Temozolomide and Temozolomide with low dose Bradykinin,studied the survival times in different groups by statistical analysis. Resnlts Temozolomide could prolong the survival times of the models,and prolonged more signally after treated with low dose Bradykinin. Conclusion Temozolomide has curative effect for glioma,low dose Bradykinin can open blood brain barrier,temozolomide combined with low dose Bradykinin can treat glioma effectively,prolong the survival times of the rat models.%目的 探讨替莫唑胺联合小剂量缓激肽对胶质瘤的治疗作用.方法 立体定向法建立大鼠C6胶质瘤模型,MRI检测胶质瘤生长情况.观察常规使用替莫唑胺及替莫唑胺联合小剂量缓激肽后C6胶质瘤大鼠的生存情况,不同组别大鼠的生存期进行统计学分析.结果 替莫唑胺可以有效延长C6胶质瘤大鼠的生存期,联合小剂量缓激肽后C6胶质瘤大鼠的生存期延长更显著.结论 替莫唑胺对胶质瘤有治疗作用,小剂量缓激肽可以选择性开放血脑屏障,替莫唑胺联合小剂量缓激肽可以有效治疗胶质瘤,延长大鼠生存期.

  5. Sensitivity Analysis of the MGMT-STP27 Model and Impact of Genetic and Epigenetic Context to Predict the MGMT Methylation Status in Gliomas and Other Tumors.

    Science.gov (United States)

    Bady, Pierre; Delorenzi, Mauro; Hegi, Monika E

    2016-05-01

    The methylation status of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene is an important predictive biomarker for benefit from alkylating agent therapy in glioblastoma. Our model MGMT-STP27 allows prediction of the methylation status of the MGMT promoter using data from the Illumina's Human Methylation BeadChips (HM-27K and HM-450K) that is publically available for many cancer data sets. Here, we investigate the impact of the context of genetic and epigenetic alterations and tumor type on the classification and report on technical aspects, such as robustness of cutoff definition and preprocessing of the data. The association between gene copy number variation, predicted MGMT methylation, and MGMT expression revealed a gene dosage effect on MGMT expression in lower grade glioma (World Health Organization grade II/III) that in contrast to glioblastoma usually carry two copies of chromosome 10 on which MGMT resides (10q26.3). This implies some MGMT expression, potentially conferring residual repair function blunting the therapeutic effect of alkylating agents. A sensitivity analyses corroborated the performance of the original cutoff for various optimization criteria and for most data preprocessing methods. Finally, we propose an R package mgmtstp27 that allows prediction of the methylation status of the MGMT promoter and calculation of appropriate confidence and/or prediction intervals. Overall, MGMT-STP27 is a robust model for MGMT classification that is independent of tumor type and is adapted for single sample prediction.

  6. 26 CFR 1.663(c)-6 - Effective dates.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Effective dates. 1.663(c)-6 Section 1.663(c)-6... Effective dates. Sections 1.663(c)-1 through 1.663(c)-5 are applicable for estates and qualified revocable... date that section 1307 of the Tax Reform Act of 1997 became effective but before December 28, 1999,...

  7. In vitro enhancement of dendritic cell-mediated anti-glioma immune response by graphene oxide

    Science.gov (United States)

    Wang, Wei; Li, Zhongjun; Duan, Jinhong; Wang, Chen; Fang, Ying; Yang, Xian-Da

    2014-06-01

    Malignant glioma has extremely poor prognosis despite combination treatments with surgery, radiation, and chemotherapy. Dendritic cell (DC)-based immunotherapy may potentially serve as an adjuvant treatment of glioma, but its efficacy generally needs further improvement. Here we explored whether graphene oxide (GO) nanosheets could modulate the DC-mediated anti-glioma immune response in vitro, using the T98G human glioma cell line as the study model. Pulsing DCs with a glioma peptide antigen (Ag) generated a limited anti-glioma response compared to un-pulsed DCs. Pulsing DCs with GO alone failed to produce obvious immune modulation effects. However, stimulating DCs with a mixture of GO and Ag (GO-Ag) significantly enhanced the anti-glioma immune reaction ( p < 0.05). The secretion of interferon gamma (IFN-γ) by the lymphocytes was also markedly boosted by GO-Ag. Additionally, the anti-glioma immune response induced by GO-Ag appeared to be target-specific. Furthermore, at the concentration used in this study, GO exhibited a negligible effect on the viability of the DCs. These results suggested that GO might have potential utility for boosting a DC-mediated anti-glioma immune response.

  8. Deeply branching c6-like cytochromes of cyanobacteria.

    Science.gov (United States)

    Bialek, Wojciech; Nelson, Matthew; Tamiola, Kamil; Kallas, Toivo; Szczepaniak, Andrzej

    2008-05-20

    The cyanobacterium Synechococcus sp. PCC 7002 carries two genes, petJ1 and petJ2, for proteins related to soluble, cytochrome c6 electron transfer proteins. PetJ1 was purified from the cyanobacterium, and both cytochromes were expressed with heme incorporation in Escherichia coli. The expressed PetJ1 displayed spectral and biochemical properties virtually identical to those of PetJ1 from Synechococcus. PetJ1 is a typical cytochrome c6 but contains an unusual KDGSKSL insertion. PetJ2 isolated from E. coli exhibited absorbance spectra characteristic of cytochromes, although the alpha, beta, and gamma bands were red-shifted relative to those of PetJ1. Moreover, the surface electrostatic properties and redox midpoint potential of PetJ2 (pI 9.7; E(m,7) = 148 +/- 1.7 mV) differed substantially from those of PetJ1 (pI 3.8; E(m,7) = 319 +/- 1.6 mV). These data indicate that the PetJ2 cytochrome could not effectively replace PetJ1 as an electron acceptor for the cytochrome bf complex in photosynthesis. Phylogenetic comparisons against plant, algal, bacterial, and cyanobacterial genomes revealed two novel and widely distributed clusters of previously uncharacterized, cyanobacterial c 6-like cytochromes. PetJ2 belongs to a group that is distinct from both c6 cytochromes and the enigmatic chloroplast c 6A cytochromes. We tentatively designate the PetJ2 group as c6C cytochromes and the other new group as c6B cytochromes. Possible functions of these cytochromes are discussed.

  9. Water-soluble l-cysteine-coated FePt nanoparticles as dual MRI/CT imaging contrast agent for glioma

    Directory of Open Access Journals (Sweden)

    Liang SY

    2015-03-01

    Full Text Available Shuyan Liang,1 Qing Zhou,1 Min Wang,2,3 Yanhong Zhu,1 Qingzhi Wu,2,3 Xiangliang Yang1 1College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 2State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, People’s Republic of China; 3Biomedical Material and Engineering Center of Hubei Province, Wuhan University of Technology, Wuhan, People’s Republic of China Abstract: Nanoparticles (NPs are advantageous for the delivery of diagnosis agents to brain tumors. In this study, we attempted to develop an l-cysteine coated FePt (FePt-Cys NP as MRI/CT imaging contrast agent for the diagnosis of malignant gliomas. FePt-Cys NPs were synthesized through a co-reduction route, which was characterized by transmission electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light scattering. The MRI and CT imaging ability of FePt-Cys NPs was evaluated using different gliomas cells (C6, SGH44, U251 as the model. Furthermore, the biocompatibility of the as-synthesized FePt-Cys NPs was evaluated using three different cell lines (ECV304, L929, and HEK293 as the model. The results showed that FePt-Cys NPs displayed excellent biocompatibility and good MRI/CT imaging ability, thereby indicating promising potential as a dual MRI/CT contrast agent for the diagnosis of brain malignant gliomas. Keywords: CT, glioma, MRI

  10. Temozolomide in malignant glioma

    Directory of Open Access Journals (Sweden)

    Gregor Dresemann

    2010-07-01

    Full Text Available Gregor DresemannCenter for Neurooncology at Aerztehaus Velen, Velen, GermanyAbstract: Glioblastoma multiforme WHO grade IV (GBM is the most aggressive ­malignant glioma and the most frequent primary tumor of the central nervous system. The median ­survival of newly diagnosed GBM patients was between 9 to 12 months prior to treatment with ­temozolomide being introduced. Primary resection that is as complete as possible is recommended for malignant glioma. Conventional fractionated irradiation 55 to 60 gy with concomitant temozolomide followed by standard temozolomide 6 cycles (5/28 (EORTC/NCIC-regime published by R Stupp in 2005 is the standard of care for newly diagnosed GBM after surgery, independent of the methylation status of the MGM-T gene promoter. Age is no ­contraindication for treatment with temozolomide, although comorbidity and performance status have to be ­considered. For temozolomide naive GBM and astrocytoma grade III patients with disease progression, temozolomide is still the treatment of choice outside of clinical studies. A ­general consensus regarding the schedule of choice has not yet been achieved; so far the 5 out of 28 days regimen (5/28 is the standard of care in most countries. Patients with disease progression after standard temozolomide (5/28 are candidates for clinical studies. Outside of clinical ­studies, dose-dense (7/7, prolonged (21/28, or metronomic (28/28 temozolomide, or alternatively a nitrosourea-based regimen can be an option. The excellent toxicity profile of ­temozolomide allows for various combinations with antitumor agents. None of these ­combinations, however, have been demonstrated to be statistically significantly superior compared to temozolomide alone. The role of lower dosed, dose-dense, or continuous regimen with or without drug combination and the role of temozolomide for newly diagnosed astrocytoma grade III and low grade glioma still has to be determined.Keywords: glioblastoma

  11. A search for ortho-benzyne (o-C6H4) in CRL 618

    CERN Document Server

    Weaver, Susanna L Widicus; McMahon, Robert J; McCall, Benjamin J

    2007-01-01

    Polycyclic aromatic hydrocarbons (PAHs) have been proposed as potential carriers of the unidentified infrared bands (UIRs) and the diffuse interstellar bands (DIBs). PAHs are not likely to form by gas-phase or solid-state interstellar chemistry, but rather might be produced in the outflows of carbon-rich evolved stars. PAHs could form from acetylene addition to the phenyl radical (C6H5), which is closely chemically related to benzene (C6H6) and $ortho$-benzyne (o-C6H4). To date, circumstellar chemical models have been limited to only a partial treatment of benzene-related chemistry, and so the expected abundances of these species are unclear. A detection of benzene has been reported in the envelope of the proto-planetary nebula (PPN) CRL 618, but no other benzene-related species has been detected in this or any other source. The spectrum of o-C6H4 is significantly simpler and stronger than that of C6H5, and so we conducted deep Ku-, K- and Q-band searches for o-C6H4 with the Green Bank Telescope. No transitio...

  12. Surgical Outcomes of High-Grade Spinal Cord Gliomas

    Science.gov (United States)

    Hida, Kazutoshi; Yano, Syunsuke; Aoyama, Takeshi; Koyanagi, Izumi; Houkin, Kiyohiro

    2015-01-01

    Study Design A retrospective study. Purpose The purpose of this study was to obtain useful information for establishing the guidelines for treating high-grade spinal cord gliomas. Overview of Literature The optimal management of high-grade spinal cord gliomas remains controversial. We report the outcomes of the surgical management of 14 high-grade spinal glioma. Methods We analyzed the outcomes of 14 patients with high-grade spinal cord gliomas who were surgically treated between 1989 and 2012. Survival was charted with the Kaplan-Meier plots and comparisons were made with the log-rank test. Results None of the patients with high-grade spinal cord gliomas underwent total resection. Subtotal resection was performed in two patients, partial resection was performed in nine patients, and open biopsy was performed in three patients. All patients underwent postoperative radiotherapy and six patients further underwent radiation cordotomy. The median survival time for patients with high-grade spinal cord gliomas was 15 months, with a 5-year survival rate of 22.2%. The median survival time for patients with World Health Organization grade III tumors was 25.5 months, whereas the median survival time for patients with glioblastoma multiforme was 12.5 months. Both univariate and multivariate Cox proportional hazards models demonstrated a significant effect only in the group that did not include cervical cord lesion as a factor associated with survival (p=0.04 and 0.03). Conclusions The surgical outcome of patients diagnosed with high-grade spinal cord gliomas remains poor. Notably, only the model which excluded cervical cord lesions as a factor significantly predicted survival. PMID:26713128

  13. RNA interference targeting hypoxia-inducible factor 1α via a novel multifunctional surfactant attenuates glioma growth in an intracranial mouse model.

    Science.gov (United States)

    Gillespie, David L; Aguirre, Maria T; Ravichandran, Sandhya; Leishman, Lisa L; Berrondo, Claudia; Gamboa, Joseph T; Wang, Libo; King, Rose; Wang, Xuli; Tan, Mingqian; Malamas, Anthony; Lu, Zheng-Rong; Jensen, Randy L

    2015-02-01

    High-grade gliomas are the most common form of adult brain cancer, and patients have a dismal survival rate despite aggressive therapeutic measures. Intratumoral hypoxia is thought to be a main contributor to tumorigenesis and angiogenesis of these tumors. Because hypoxia-inducible factor 1α (HIF-1α) is the major mediator of hypoxia-regulated cellular control, inhibition of this transcription factor may reduce glioblastoma growth. Using an orthotopic mouse model with U87-LucNeo cells, the authors used RNA interference to knock down HIF-1α in vivo. The small interfering RNA (siRNA) was packaged using a novel multifunctional surfactant, 1-(aminoethyl) iminobis[N-(oleicylcysteinylhistinyl-1-aminoethyl)propionamide] (EHCO), a nucleic acid carrier that facilitates cellular uptake and intracellular release of siRNA. Stereotactic injection was used to deliver siRNA locally through a guide-screw system, and delivery/uptake was verified by imaging of fluorescently labeled siRNA. Osmotic pumps were used for extended siRNA delivery to model a commonly used human intracranial drug-delivery technique, convection-enhanced delivery. Mice receiving daily siRNA injections targeting HIF-1α had a 79% lower tumor volume after 50 days of treatment than the controls. Levels of the HIF-1 transcriptional targets vascular endothelial growth factor (VEGF), glucose transporter 1 (GLUT-1), c-MET, and carbonic anhydrase-IX (CA-IX) and markers for cell growth (MIB-1 and microvascular density) were also significantly lower. Altering the carrier EHCO by adding polyethylene glycol significantly increased the efficacy of drug delivery and subsequent survival. Treating glioblastoma with siRNA targeting HIF-1α in vivo can significantly reduce tumor growth and increase survival in an intracranial mouse model, a finding that has direct clinical implications.

  14. Tricyclic Neovibsanin Scaffold Inhibits Glioma by Targeting Glioma ...

    African Journals Online (AJOL)

    formation capacity and induction of apoptosis in glioma cells. Methods: ... present in plants and possess polyfunctional structures ... the ethics and review committee for the animal studies at .... adhered and started to differentiate forming U138.

  15. Mature brain-derived neurotrophic factor and its receptor TrkB are upregulated in human glioma tissues.

    Science.gov (United States)

    Xiong, Jing; Zhou, L I; Lim, Yoon; Yang, Miao; Zhu, Yu-Hong; Li, Zhi-Wei; Fu, Deng-Li; Zhou, Xin-Fu

    2015-07-01

    There are two forms of brain-derived neurotrophic factor (BDNF), precursor of BDNF (proBDNF) and mature BDNF, which each exert opposing effects through two different transmembrane receptor signaling systems, consisting of p75 neurotrophin receptor (p75NTR) and tyrosine receptor kinase B (TrkB). Previous studies have demonstrated that proBDNF promotes cell death and inhibits the growth and migration of C6 glioma cells through p75NTR in vitro, while mature BDNF has opposite effects on C6 glioma cells. It is hypothesized that mature BDNF is essential in the development of malignancy in gliomas. However, histological data obtained in previous studies were unable distinguish mature BDNF from proBDNF due to the lack of specific antibodies. The present study investigated the expression of mature BDNF using a specific sheep monoclonal anti-mature BDNF antibody in 42 human glioma tissues of different grades and 10 control tissues. The correlation between mature BDNF and TrkB was analyzed. Mature BDNF expression was significantly increased in high-grade gliomas, and was positively correlated with the malignancy of the tumor and TrkB receptor expression. The present data have demonstrated that increased levels of mature BDNF contribute markedly to the development of malignancy of human gliomas through the primary BDNF receptor TrkB.

  16. Invasion of primary glioma- and cell line-derived spheroids implanted into corticostriatal slice cultures

    DEFF Research Database (Denmark)

    Aaberg-Jessen, Charlotte; Nørregaard, Annette; Christensen, Karina

    2013-01-01

    preserving the invasive features and stem cell features of glioma cells. Fluorescently labelled primary glioma spheroids and U87MG cell line-derived spheroids were implanted into organotypic rat corticostriatal slice cultures and the invasion was followed over time by confocal microscopy. The invasion......Gliomas are highly invasive tumors and the pronounced invasive features of gliomas prevent radical surgical resection. In the search for new therapeutics targeting invasive glioma cells, in vivo-like in vitro models are of great interest. We developed and evaluated an in vivo-like in vitro model...... was validated immunohistochemically with paraffin sections using a human-specific vimentin antibody. Moreover, the preservation of immature stem cell features was evaluated immunohistochemically using the stem cell markers CD133, Sox2, Bmi-1 and nestin. The confocal and immunohistochemical results showed...

  17. Carboxyl terminus of Hsp70-interacting protein (CHIP) contributes to human glioma oncogenesis.

    Science.gov (United States)

    Xu, Tao; Zhou, Quan; Zhou, Jingxu; Huang, Yan; Yan, Yong; Li, Weiqing; Wang, Chunlin; Hu, Guohan; Lu, Yicheng; Chen, Juxiang

    2011-05-01

    Malignant glioma is the most common adult primary brain tumor, and the mechanism of its oncogenesis is poorly understood. Growing evidence has shown that E3 ubiquitin ligases can promote tumorgenesis of glioma. CHIP is an E3 ubiquitin ligase that can induce ubiquitylation and degradation of many tumor-related proteins, and it has been reported to act as an upstream regulator in breast cancer; however, its role in human gliomas has not been evaluated yet. In this study, the expression of CHIP in glioma tissues was studied using immunohistochemistry. CHIP expression in glioma cells was studied by real-time RT-PCR, western blot and double immunofluorescence staining. The role of CHIP in glioma oncogenesis was investigated by lentivirus-mediated RNA interference (RNAi) and overexpression in vitro and in vivo. We showed CHIP expression in glioma samples was related to tumor grades, with stronger staining in high-grade gliomas than in low-grade gliomas. Knocking down of CHIP suppressed proliferation, colony formation of U251 and U87 glioma cells, while overexpression of CHIP resulted in enhanced proliferation and colony formation in vitro. In a nude mouse xenograft model, intratumoral injection of CHIP RNAi lentivirus significantly delayed tumor growth. In contrast, overexpression of CHIP resulted in enhanced tumor growth in vivo. After CHIP RNAi, both survivin mRNA and protein were decreased, while CHIP overexpression induced increased mRNA and protein levels of survivin. This is the first study demonstrating CHIP contributes to oncogenesis of glioma. © 2011 Japanese Cancer Association.

  18. Convection-enhanced delivery of Ls-TPT enables an effective, continuous, low-dose chemotherapy against malignant glioma xenograft model1

    Science.gov (United States)

    Saito, Ryuta; Krauze, Michal T.; Noble, Charles O.; Drummond, Daryl C.; Kirpotin, Dmitri B.; Berger, Mitchel S.; Park, John W.; Bankiewicz, Krystof S.

    2006-01-01

    Treatment of malignant gliomas represents one of the most formidable challenges in oncology. The combination of surgery, radiation, and chemotherapy yields median survivals of less than one year. Here we demonstrate the use of a minimally invasive surgical technique, convection-enhanced delivery (CED), for local administration of a novel nanoparticle liposome containing topotecan. CED of this liposomal topotecan (Ls-TPT) resulted in extended brain tissue retention (t½ = 1.5 days), whereas free topotecan was rapidly cleared (t½ = 0.1 days) after CED. The favorable pharmacokinetic profile of extended topotecan release for about seven days, along with biodistribution featuring perivascular accumulation of the nanoparticles, provided, in addition to the known topoisomerase I inhibition, an effective antiangiogenic therapy. In the rat intracranial U87MG tumor model, vascular targeting of Ls-TPT with CED was associated with reductions in laminin expression and vascular density compared to free topotecan or control treatments. A single CED treatment on day 7 showed that free topotecan conferred no survival benefit versus control. However, Ls-TPT produced a significant (P = 0.0002) survival benefit, with six of seven complete cures. Larger U87MG tumors, where CED of Ls-TPT on day 12 resulted in one of six cures, indicated the necessity to cover the entire tumor with the infused therapeutic agent. CED of Ls-TPT was also efficacious in the intracranial U251MG tumor model (P = 0.0005 versus control). We conclude that the combination of a novel nanoparticle Ls-TPT and CED administration was very effective in treating experimental brain tumors. PMID:16723630

  19. Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells.

    Science.gov (United States)

    Ma, Jian; Yang, Yan-Ru; Chen, Wei; Chen, Mei-Hua; Wang, Hao; Wang, Xiao-Dan; Sun, Li-Li; Wang, Feng-Ze; Wang, De-Cai

    2016-08-01

    Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP‑dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with

  20. SURFACE MULTI-FUNCTIONALIZATION OF POLY(LACTIC ACID)NANOPARTICLES AND C6 GLIOMA CELL TARGETING in vivo

    Institute of Scientific and Technical Information of China (English)

    Xu-bo Yuan; Chun-sheng Kang; Yun-hui Zhao; Ming-qi Gu; Pei-yu Pu

    2009-01-01

    Polysaccharide coated PLA nanopartieles bearing aldehyde groups were prepared by dialysis of DMSO solution of cholesterol hydrophobic-modified dextran polyaldehyde and PLA against water.The average diameter of the nanoparticles was about 160 nm,and the size distribution was nearly homogenous.The nanoparticles were functionalized simultaneously with CD71 and EGFR antibody through the Schiff's base reaction,and then radiolabeled with 99mTc.After perfused the radiolabeled nanoparticles into tumor-bearing rats through left common carotid artery,the radioactivity in liver,spleen,kidney and brain was measured by scintillation counter.The results showed that less than 2% of nanoparticles were uptaken by the brain due to the uptake of the nanoparticles by the RES system.However,the coupling of transferrin antibody on the nanoparticles facilitated the penetration of nanoparticles across the blood brain barrier,and more specially,compared with monofuctionalized and native nanoparticles,the multifunctionalization enhanced the tumor accumulation of the nanoparticles in vivo.

  1. Angiogenic Signalling Pathways Altered in Gliomas: Selection Mechanisms for More Aggressive Neoplastic Subpopulations with Invasive Phenotype

    Directory of Open Access Journals (Sweden)

    Susana Bulnes

    2012-01-01

    Full Text Available The angiogenesis process is a key event for glioma survival, malignancy and growth. The start of angiogenesis is mediated by a cascade of intratumoural events: alteration of the microvasculature network; a hypoxic microenvironment; adaptation of neoplastic cells and synthesis of pro-angiogenic factors. Due to a chaotic blood flow, a consequence of an aberrant microvasculature, tissue hypoxia phenomena are induced. Hypoxia inducible factor 1 is a major regulator in glioma invasiveness and angiogenesis. Clones of neoplastic cells with stem cell characteristics are selected by HIF-1. These cells, called “glioma stem cells” induce the synthesis of vascular endothelial growth factor. This factor is a pivotal mediator of angiogenesis. To elucidate the role of these angiogenic mediators during glioma growth, we have used a rat endogenous glioma model. Gliomas induced by prenatal ENU administration allowed us to study angiogenic events from early to advanced tumour stages. Events such as microvascular aberrations, hypoxia, GSC selection and VEGF synthesis may be studied in depth. Our data showed that for the treatment of gliomas, developing anti-angiogenic therapies could be aimed at GSCs, HIF-1 or VEGF. The ENU-glioma model can be considered to be a useful option to check novel designs of these treatment strategies.

  2. Angiogenic Signalling Pathways Altered in Gliomas: Selection Mechanisms for More Aggressive Neoplastic Subpopulations with Invasive Phenotype

    Science.gov (United States)

    Bulnes, Susana; Bengoetxea, Harkaitz; Ortuzar, Naiara; Argandoña, Enrike G.; Garcia-Blanco, Álvaro; Rico-Barrio, Irantzu; Lafuente, José V.

    2012-01-01

    The angiogenesis process is a key event for glioma survival, malignancy and growth. The start of angiogenesis is mediated by a cascade of intratumoural events: alteration of the microvasculature network; a hypoxic microenvironment; adaptation of neoplastic cells and synthesis of pro-angiogenic factors. Due to a chaotic blood flow, a consequence of an aberrant microvasculature, tissue hypoxia phenomena are induced. Hypoxia inducible factor 1 is a major regulator in glioma invasiveness and angiogenesis. Clones of neoplastic cells with stem cell characteristics are selected by HIF-1. These cells, called “glioma stem cells” induce the synthesis of vascular endothelial growth factor. This factor is a pivotal mediator of angiogenesis. To elucidate the role of these angiogenic mediators during glioma growth, we have used a rat endogenous glioma model. Gliomas induced by prenatal ENU administration allowed us to study angiogenic events from early to advanced tumour stages. Events such as microvascular aberrations, hypoxia, GSC selection and VEGF synthesis may be studied in depth. Our data showed that for the treatment of gliomas, developing anti-angiogenic therapies could be aimed at GSCs, HIF-1 or VEGF. The ENU-glioma model can be considered to be a useful option to check novel designs of these treatment strategies. PMID:22852079

  3. Formation and stabilization of C6- by radiative electron attachment

    Science.gov (United States)

    Chandrasekaran, Vijayanand; Prabhakaran, Aneesh; Kafle, Bhim; Rubinstein, Hilel; Heber, Oded; Rappaport, Michael; Toker, Yoni; Zajfman, Daniel

    2017-03-01

    Radiative electron attachment (REA) plays an important role in forming molecular anions in various astrophysical environments. In this work, we determined the rate coefficient for the formation of C6- by REA based on a detailed balance approach. C6- ions are stored in an electrostatic ion beam trap and are photoexcited above their adiabatic detachment energy (4.18 eV). Due to fast internal conversion and intramolecular vibrational redistribution, photoexcitation leads to the formation of temporary negative ions (TNIs), the same as those one formed by the electron attachment. Absolute vibrational autodetachment and recurrent (or Poincaré) fluorescence (RF) rate coefficients have already been reported [V. Chandrasekaran et al., J. Phys. Chem. Lett. 5, 4078 (2014)]. Knowing the branching ratios of the various competing rate coefficients is decisive to the understanding of the formation probability of anions via REA. The radiative stabilization rate of C6-, shown to be dominated by RF, was determined to be 5 × 104 s-1 at the electron detachment energy, i.e., at least a factor of 100 faster than the stabilization by infrared transitions. The RF is found to very effectively stabilize the TNI formed by electron attachment. Using detailed balance to link the measured delayed detachment rate to the rate of electron attachment, we estimate the REA rate leading to the formation of C6- to be 3 × 10-7 cm3 s-1 at 300 K in agreement with theory (1.7 × 10-7 cm3 s-1 [R. Terzieva and E. Herbst, Int. J. Mass Spectrom. 201, 135 (2000)]). Such a high rate for REA to C6 indicates that REA may play a prominent role in the formation of anions in the interstellar medium.

  4. [Controversy on treatments for gliomas].

    Science.gov (United States)

    Nomura, K

    1998-09-01

    Gliomas are representative primary malignant brain tumors, and with such tumors it is difficult to define the advanced stage. If the advanced stage indicates no curability by surgery alone, most gliomas would belong to this criterion because of their poor prognosis without any completely effective treatment. In this sense, no one could show a standard therapy to treat these unfortunate patients, for example, patients with glioblastoma, they could permit only 1 year survived even they had any applicable treatments to the lesions, these days. Treatment for low-grade gliomas has been most controversial for a long time, and no standard treatments have been determined so far. In this paper, as the treatment of low-grade gliomas it was intended to report what must be done for this patient and the present results of opinion survey for the treatment of gliomas which was done to professors of 80 institutes, from schools of medicine at all universities and medical colleges in Japan. For high-grade gliomas, some effectiveness of radiation therapy was disclosed as well as chemotherapy from recent papers. Gene therapy was also discussed briefly, its present status and future.

  5. Quantitative correlational study of microbubble-enhanced ultrasound imaging and magnetic resonance imaging of glioma and early response to radiotherapy in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chen [Department of Ultrasound, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022 (China); Lee, Dong-Hoon; Zhang, Kai; Li, Wenxiao; Zhou, Jinyuan [Division of MR Research, Department of Radiology, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21287 (United States); Mangraviti, Antonella; Tyler, Betty [Department of Neurosurgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21287 (United States); Su, Lin; Zhang, Yin; Zhang, Bin; Wong, John; Wang, Ken Kang-Hsin; Velarde, Esteban; Ding, Kai, E-mail: kding1@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21231 (United States)

    2015-08-15

    Purpose: Radiotherapy remains a major treatment method for malignant tumors. Magnetic resonance imaging (MRI) is the standard modality for assessing glioma treatment response in the clinic. Compared to MRI, ultrasound imaging is low-cost and portable and can be used during intraoperative procedures. The purpose of this study was to quantitatively compare contrast-enhanced ultrasound (CEUS) imaging and MRI of irradiated gliomas in rats and to determine which quantitative ultrasound imaging parameters can be used for the assessment of early response to radiation in glioma. Methods: Thirteen nude rats with U87 glioma were used. A small thinned skull window preparation was performed to facilitate ultrasound imaging and mimic intraoperative procedures. Both CEUS and MRI with structural, functional, and molecular imaging parameters were performed at preradiation and at 1 day and 4 days postradiation. Statistical analysis was performed to determine the correlations between MRI and CEUS parameters and the changes between pre- and postradiation imaging. Results: Area under the curve (AUC) in CEUS showed significant difference between preradiation and 4 days postradiation, along with four MRI parameters, T{sub 2}, apparent diffusion coefficient, cerebral blood flow, and amide proton transfer-weighted (APTw) (all p < 0.05). The APTw signal was correlated with three CEUS parameters, rise time (r = − 0.527, p < 0.05), time to peak (r = − 0.501, p < 0.05), and perfusion index (r = 458, p < 0.05). Cerebral blood flow was correlated with rise time (r = − 0.589, p < 0.01) and time to peak (r = − 0.543, p < 0.05). Conclusions: MRI can be used for the assessment of radiotherapy treatment response and CEUS with AUC as a new technique and can also be one of the assessment methods for early response to radiation in glioma.

  6. Quantitative correlational study of microbubble-enhanced ultrasound imaging and magnetic resonance imaging of glioma and early response to radiotherapy in a rat model.

    Science.gov (United States)

    Yang, Chen; Lee, Dong-Hoon; Mangraviti, Antonella; Su, Lin; Zhang, Kai; Zhang, Yin; Zhang, Bin; Li, Wenxiao; Tyler, Betty; Wong, John; Wang, Ken Kang-Hsin; Velarde, Esteban; Zhou, Jinyuan; Ding, Kai

    2015-08-01

    Radiotherapy remains a major treatment method for malignant tumors. Magnetic resonance imaging (MRI) is the standard modality for assessing glioma treatment response in the clinic. Compared to MRI, ultrasound imaging is low-cost and portable and can be used during intraoperative procedures. The purpose of this study was to quantitatively compare contrast-enhanced ultrasound (CEUS) imaging and MRI of irradiated gliomas in rats and to determine which quantitative ultrasound imaging parameters can be used for the assessment of early response to radiation in glioma. Thirteen nude rats with U87 glioma were used. A small thinned skull window preparation was performed to facilitate ultrasound imaging and mimic intraoperative procedures. Both CEUS and MRI with structural, functional, and molecular imaging parameters were performed at preradiation and at 1 day and 4 days postradiation. Statistical analysis was performed to determine the correlations between MRI and CEUS parameters and the changes between pre- and postradiation imaging. Area under the curve (AUC) in CEUS showed significant difference between preradiation and 4 days postradiation, along with four MRI parameters, T2, apparent diffusion coefficient, cerebral blood flow, and amide proton transfer-weighted (APTw) (all p correlated with three CEUS parameters, rise time (r = - 0.527, p correlated with rise time (r = - 0.589, p < 0.01) and time to peak (r = - 0.543, p < 0.05). MRI can be used for the assessment of radiotherapy treatment response and CEUS with AUC as a new technique and can also be one of the assessment methods for early response to radiation in glioma.

  7. Hyperbaric oxygen promotes malignant glioma cell growth and inhibits cell apoptosis.

    Science.gov (United States)

    Wang, Yong-Gang; Zhan, Yi-Ping; Pan, Shu-Yi; Wang, Hai-Dong; Zhang, Dun-Xiao; Gao, Kai; Qi, Xue-Ling; Yu, Chun-Jiang

    2015-07-01

    Glioblastoma multiforme (GBM) is the most frequently diagnosed intracranial malignant tumor in adults. Clinical studies have indicated that hyperbaric oxygen may improve the prognosis and reduce complications in glioma patients; however, the specific mechanism by which this occurs remains unknown. The present study investigated the direct effects of hyperbaric oxygen stimulation on glioma by constructing an intracranial transplanted glioma model in congenic C57BL/6J mice. Bioluminescent imaging (BLI) was used to assess the growth of intracranial transplanted GL261-Luc glioma cells in vivo, while flow cytometric and immunohistochemical assays were used to detect and compare the expression of the biomarkers, Ki-67, CD34 and TUNEL, reflecting the cell cycle, apoptosis and angiogenesis. BLI demonstrated that hyperbaric oxygen promoted the growth of intracranially transplanted GL261-Luc glioma cells in vivo. Flow cytometric analysis indicated that hyperbaric oxygen promoted GL261-Luc glioma cell proliferation and also prevented cell cycle arrest. In addition, hyperbaric oxygen inhibited the apoptosis of the transplanted glioma cells. Immunohistochemical analysis also indicated that hyperbaric oxygen increased positive staining for Ki-67 and CD34, while reducing staining for TUNEL (a marker of apoptosis). The microvessel density was significantly increased in the hyperbaric oxygen treatment group compared with the control group. In conclusion, hyperbaric oxygen treatment promoted the growth of transplanted malignant glioma cells in vivo and also inhibited the apoptosis of these cells.

  8. Molecular Mechanisms Involved in the Antitumor Activity of Cannabinoids on Gliomas: Role for Oxidative Stress

    Energy Technology Data Exchange (ETDEWEB)

    Massi, Paola [Department of Pharmacology, Chemotherapy and Toxicology, University of Milan, Via Vanvitelli 32, 20129 Milan (Italy); Valenti, Marta; Solinas, Marta; Parolaro, Daniela, E-mail: daniela.parolaro@uninsubria.it [Department of Structural and Functional Biology, Section of Pharmacology, Center of Neuroscience, University of Insubria, Via A. da Giussano 10, 20152 Busto Arsizio, Varese (Italy)

    2010-05-26

    Cannabinoids, the active components of Cannabis sativa, have been shown to exert antiproliferative and proapoptotic effects on a wide spectrum of tumor cells and tissues. Of interest, cannabinoids have displayed great potency in reducing the growth of glioma tumors, one of the most aggressive CNS tumors, either in vitro or in animal experimental models curbing the growth of xenografts generated by subcutaneous or intrathecal injection of glioma cells in immune-deficient mice. Cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of non-transformed cells. This review will summarize the anti-cancer properties that cannabinoids exert on gliomas and discuss their potential action mechanisms that appear complex, involving modulation of multiple key cell signaling pathways and induction of oxidative stress in glioma cells.

  9. Molecular Mechanisms Involved in the Antitumor Activity of Cannabinoids on Gliomas: Role for Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Paola Massi

    2010-05-01

    Full Text Available Cannabinoids, the active components of Cannabis sativa, have been shown to exert antiproliferative and proapoptotic effects on a wide spectrum of tumor cells and tissues. Of interest, cannabinoids have displayed great potency in reducing the growth of glioma tumors, one of the most aggressive CNS tumors, either in vitro or in animal experimental models curbing the growth of xenografts generated by subcutaneous or intrathecal injection of glioma cells in immune-deficient mice. Cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of non-transformed cells. This review will summarize the anti-cancer properties that cannabinoids exert on gliomas and discuss their potential action mechanisms that appear complex, involving modulation of multiple key cell signaling pathways and induction of oxidative stress in glioma cells.

  10. Sulfasalazine unveils a contact-independent HSV-TK/ganciclovir gene therapy bystander effect in malignant gliomas.

    Science.gov (United States)

    Robe, Pierre A; Nguyen-Khac, Minh-Tuan; Lambert, Frederic; Lechanteur, Chantal; Jolois, Olivier; Ernst-Gengoux, Patricia; Rogister, Bernard; Bours, Vincent

    2007-01-01

    The efficacy of HSV-TK/ganciclovir-based gene therapy on malignant gliomas largely relies on the amplitude of the bystander effect. In these experiments, the anti-inflammatory drug Sulfasalazine increased the HSV-TK/ganciclovir bystander effect in C6, 9L and LN18 cells but not in U87 glioma cells. Using bi-compartmental culture devices and conditioned medium transfer experiments, we showed that in C6, 9L and LN18 cells but not in U87 cells, Sulfasalazine also unveiled a new, contact-independent mechanism of HSV-TK/ganciclovir bystander effect. Upon treatment with ganciclovir, human LN18-TK but not U87-TK cells synthetized and released TNF-alpha in the culture medium. Sulfasalazine sensitized glioma cells to the toxic effect of TNF-alpha and enhanced its secretion in LN18-TK cells in response to GCV treatment. The caspase-8 inhibitor Z-IETD-FMK and a blocking antibody to TNF-alpha both inhibited the contact-independent bystander effect in LN18 cells. Taken together, these results suggest that TNF-alpha mediates the contact-independent bystander effect in LN18 cells. The treatment with GCV and/or Sulfasalazine of tumor xenografts consisting of a mix of 98% C6 and 2% C6-TK cells shows that Sulfasalazine is also a potent adjunct to the in vivo treatment of gliomas.

  11. Cannabinoids as potential new therapy for the treatment of gliomas.

    Science.gov (United States)

    Parolaro, Daniela; Massi, Paola

    2008-01-01

    Gliomas constitute the most frequent and malignant primary brain tumors. Current standard therapeutic strategies (surgery, radiotherapy and chemotherapeutics, e.g., temozolomide, carmustin or carboplatin) for their treatment are only palliative and survival diagnosis is normally 6-12 months. The development of new therapeutic strategies for the management of gliomas is therefore essential. Interestingly, cannabinoids have been shown to exert antiproliferative effects on a wide spectrum of cells in culture. Of interest, cannabinoids have displayed a great potency in reducing glioma tumor growth either in vitro or in animal experimental models, curbing the growth of xenografts generated by subcutaneous or intratecal injection of glioma cells in immune-deficient mice. Moreover, cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of nontransformed counterparts. A pilot clinical trial on patients with glioblastoma multiforme demonstrated their good safety profile together and remarkable antitumor effects, and may set the basis for further studies aimed at better evaluating the potential anticancer activity of cannabinoids.

  12. 氧自由基与脑胶质瘤瘤周水肿关系的实验研究%Relationship Between Oxygen Free Radical and Peritumor Edema in Glioma

    Institute of Scientific and Technical Information of China (English)

    赵心同; 赵洪洋; 姚东晓; 王海均

    2011-01-01

    目的:探讨自由基和脑胶质瘤瘤周水肿的关系.方法:体外培养大鼠C6脑胶质瘤细胞株,采用立体定向技术将细胞株接种在右侧尾状核,建立大鼠脑胶质瘤模型,共60只,术后5天将荷瘤大鼠随机分为3组(EDA高剂量组,EDA低剂量组和对照组),每组各20只,每组10只用来测定荷瘤大鼠瘤周脑组织含水量、SOD活性及MDA含量,剩余10只用来观察荷瘤大鼠生存时间.结果:EDA干预组荷瘤大鼠瘤周脑组织含水量下降,SOD活性增高,MDA含量下降,以EDA高剂量组更为显著.各组荷瘤大鼠瘤周脑组织含水量与SOD活性呈负相关,而与MDA含量呈正相关.且EDA组荷瘤大鼠生存时间延长.结论:由基参与大鼠脑胶质瘤瘤周水肿的形成,自由基清除剂能够减轻大鼠脑胶质瘤瘤周脑组织水肿.%Objective: To investigate the relationship between oxygen free radical and peritumor edema in glioma. Methods: The rat C6 glioma cells were cultivated in vitro. The suspention of C6 glioma cells was stereotaxically injected into right caudate to establish rat C6 glioma model. After surgery, all rat glioma models were randomly classified into 3 groups (edaravone-trteated group in high dose,edaravone-trteated group in low dose and control group). Each group had twenty rats. Ten rats from each group were used to determine the moisture content in peritumor brain tissues, SOD activity and the content of MDA. The other 10 rats were used to detect the survival time after surgery. Results: The decreased moisture and MDA contents in peritumor brain tissues and increased SOD activity were found in edaravune-treated group, especially in high dose. The survival time was longer in edaravone-treated group than that of control group.Conclusion: Oxygen free radical is involved in the formation of peritumor edema in glioma, and the free radical scavenger may reduce the peritumor edema in glioma.

  13. Fatty acid oxidation is required for the respiration and proliferation of malignant glioma cells.

    Science.gov (United States)

    Lin, Hua; Patel, Shaan; Affleck, Valerie S; Wilson, Ian; Turnbull, Douglass M; Joshi, Abhijit R; Maxwell, Ross; Stoll, Elizabeth A

    2017-01-01

    Glioma is the most common form of primary malignant brain tumor in adults, with approximately 4 cases per 100 000 people each year. Gliomas, like many tumors, are thought to primarily metabolize glucose for energy production; however, the reliance upon glycolysis has recently been called into question. In this study, we aimed to identify the metabolic fuel requirements of human glioma cells. We used database searches and tissue culture resources to evaluate genotype and protein expression, tracked oxygen consumption rates to study metabolic responses to various substrates, performed histochemical techniques and fluorescence-activated cell sorting-based mitotic profiling to study cellular proliferation rates, and employed an animal model of malignant glioma to evaluate a new therapeutic intervention. We observed the presence of enzymes required for fatty acid oxidation within human glioma tissues. In addition, we demonstrated that this metabolic pathway is a major contributor to aerobic respiration in primary-cultured cells isolated from human glioma and grown under serum-free conditions. Moreover, inhibiting fatty acid oxidation reduces proliferative activity in these primary-cultured cells and prolongs survival in a syngeneic mouse model of malignant glioma. Fatty acid oxidation enzymes are present and active within glioma tissues. Targeting this metabolic pathway reduces energy production and cellular proliferation in glioma cells. The drug etomoxir may provide therapeutic benefit to patients with malignant glioma. In addition, the expression of fatty acid oxidation enzymes may provide prognostic indicators for clinical practice. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.

  14. Determination of the Cu(110)-c(6X2)-O structure by x-ray diffraction

    DEFF Research Database (Denmark)

    Feidenhans'l, R.; Grey, F.; Johnson, R.L.

    1991-01-01

    We have performed a structural determination of the Cu(110)-c(6 X 2)-O surface by x-ray diffraction. A model including only copper atoms is found on the basis of the Patterson function; the positions of the oxygen atoms are revealed in an electron-density-difference map. The final structure has a...

  15. Enhanced cell growth and tumorigenicity of rat glioma cells by stable expression of human CD133 through multiple molecular actions.

    Science.gov (United States)

    Fang, Kuan-Min; Lin, Tzu-Chien; Chan, Ti-Chun; Ma, Shi-Zhang; Tzou, Bo-Cheng; Chang, Wen-Ruei; Liu, Jun-Jen; Chiou, Shih-Hwa; Yang, Chung-Shi; Tzeng, Shun-Fen

    2013-09-01

    CD133 (Prominin-1/AC133) is generally treated as a cell surface marker found on multipotent stem cells and tumor stem-like cells, and its biological function remains debated. Genetically modified rat glioma cell lines were generated by lentiviral gene delivery of human CD133 into rat C6 glioma cells (hCD133(+) -C6) or by infection of C6 cells with control lentivirus (mock-C6). Stable hCD133 expression promoted the self-renewal ability of C6-formed spheres with an increase in the expression of the stemness markers, Bmi-1 and SOX2. Akt phosphorylation, Notch-1 activation, and Notch-1 target gene expression (Hes-1, Hey1 and Hey2) were increased in hCD133(+) -C6 when compared to mock-C6. The inhibition of Akt phosphorylation, Notch-1 activation, and Hes-1 in hCD133(+) -C6 cells effectively suppressed their clonogenic ability, indicating that these factors are involved in expanding the growth of hCD133(+) -C6. An elevated expression of GTPase-activating protein 27 (Arhgap27) was detected in hCD133(+) -C6. A decline in the invasion of hCD133(+) -C6 by knockdown of Arhgap27 expression indicated the critical role of Arhgap27 in promoting cell migration of hCD133(+) -C6. In vivo study further showed that hCD133(+) -C6 formed aggressive tumors in vivo compared to mock-C6. Exposure of hCD133(+) -C6 to arsenic trioxide not only reduced Akt phosphorylation, Notch-1 activation and Hes-1 expression in vitro, but also inhibited their tumorigenicity in vivo. The results show that C6 glioma cells with stable hCD133 expression enhanced their stemness properties with increased Notch-1/Hes-1 signaling, Akt activation, and Arhgap27 action, which contribute to increased cell proliferation and migration of hCD133(+) -C6 in vitro, as well as progressive tumor formation in vivo.

  16. Notch Promotes Radioresistance of Glioma Stem Cells

    OpenAIRE

    Wang, Jialiang; Wakeman, Timothy P.; Latha, Justin D.; Hjelmeland, Anita B.; Wang, Xiao-Fan; White, Rebekah R.; Rich, Jeremy N.; Sullenger, Bruce A.

    2010-01-01

    Radiotherapy represents the most effective nonsurgical treatments for gliomas. Yet, gliomas are highly radioresistant and recurrence is nearly universal. Results from our laboratory and other groups suggest that cancer stem cells contribute to radioresistance in gliomas and breast cancers. The Notch pathway is critically implicated in stem cell fate determination and cancer. In this study, we showed that inhibition of Notch pathway with gamma-secretase inhibitors (GSIs) rendered the glioma st...

  17. Use of statins and risk of glioma

    DEFF Research Database (Denmark)

    Gaist, David; Andersen, L; Hallas, Jesper;

    2013-01-01

    Laboratory studies and a single case-control study have suggested a protective effect of statins on the risk of glioma. We wished to investigate the influence of statin use on the risk of glioma in a population-based setting.......Laboratory studies and a single case-control study have suggested a protective effect of statins on the risk of glioma. We wished to investigate the influence of statin use on the risk of glioma in a population-based setting....

  18. Mechanisms of Glioma Formation: Iterative Perivascular Glioma Growth and Invasion Leads to Tumor Progression, VEGF-Independent Vascularization, and Resistance to Antiangiogenic Therapy

    Directory of Open Access Journals (Sweden)

    Gregory J. Baker

    2014-07-01

    Full Text Available As glioma cells infiltrate the brain they become associated with various microanatomic brain structures such as blood vessels, white matter tracts, and brain parenchyma. How these distinct invasion patterns coordinate tumor growth and influence clinical outcomes remain poorly understood. We have investigated how perivascular growth affects glioma growth patterning and response to antiangiogenic therapy within the highly vascularized brain. Orthotopically implanted rodent and human glioma cells are shown to commonly invade and proliferate within brain perivascular space. This form of brain tumor growth and invasion is also shown to characterize de novo generated endogenous mouse brain tumors, biopsies of primary human glioblastoma (GBM, and peripheral cancer metastasis to the human brain. Perivascularly invading brain tumors become vascularized by normal brain microvessels as individual glioma cells use perivascular space as a conduit for tumor invasion. Agent-based computational modeling recapitulated biological perivascular glioma growth without the need for neoangiogenesis. We tested the requirement for neoangiogenesis in perivascular glioma by treating animals with angiogenesis inhibitors bevacizumab and DC101. These inhibitors induced the expected vessel normalization, yet failed to reduce tumor growth or improve survival of mice bearing orthotopic or endogenous gliomas while exacerbating brain tumor invasion. Our results provide compelling experimental evidence in support of the recently described failure of clinically used antiangiogenics to extend the overall survival of human GBM patients.

  19. Imaging of adult brainstem gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Purohit, Bela, E-mail: purohitbela@yahoo.co.in; Kamli, Ali A.; Kollias, Spyros S.

    2015-04-15

    Highlights: •BSG are classified on MRI into diffuse low-grade, malignant, focal tectal and exophytic subtypes. •Their prognosis and treatment is variable and is almost similar to adult supratentorial gliomas. •This article illustrates the imaging of adult BSGs on MRI and FET-PET. •We also describe prognostic factors and the treatment options of these tumours. -- Abstract: Brainstem gliomas (BSGs) are uncommon in adults accounting for about 2% of all intracranial neoplasms. They are often phenotypically low-grade as compared to their more common paediatric counterparts. Since brainstem biopsies are rarely performed, these tumours are commonly classified according to their MR imaging characteristics into 4 subgroups: (a) diffuse intrinsic low-grade gliomas, (b) enhancing malignant gliomas, (c) focal tectal gliomas and (d) exophytic gliomas/other subtypes. The prognosis and treatment is variable for the different types and is almost similar to adult supratentorial gliomas. Radiotherapy (RT) with adjuvant chemotherapy is the standard treatment of diffuse low-grade and malignant BSGs, whereas, surgical resection is limited to the exophytic subtypes. Review of previous literature shows that the detailed imaging of adult BSGs has not received significant attention. This review illustrates in detail the imaging features of adult BSGs using conventional and advanced MR techniques like diffusion weighted imaging (DWI), diffusion tensor imaging (DTI), MR perfusion weighted imaging (PWI), MR spectroscopy (MRS), as well as {sup 18}F-fluoro-ethyl-tyrosine positron emission tomography ({sup 18}F-FET/PET). We have discussed the pertinent differences between childhood and adult BSGs, imaging mimics, prognostic factors and briefly reviewed the treatment options of these tumours.

  20. The engineered Salmonella typhimurium inhibits tumorigenesis in advanced glioma

    Directory of Open Access Journals (Sweden)

    Chen JQ

    2015-09-01

    Full Text Available Jian-qiang Chen,1 Yue-fu Zhan,2 Wei Wang,1 Sheng-nan Jiang,2,3 Xiang-ying Li21Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, People’s Republic of China; 2Department of Radiology, Affiliated to Haikou Hospital Xiangya School of Medicine, Central South University, Haikou, People’s Republic of China; 3Department of Nuclear Medicine, Central South University Xiangya School of Medicine Affiliated HaiKou Hospital, Haikou, Hainan, People’s Republic of ChinaObjective: To explore the antitumor role of the attenuated Salmonella typhimurium ΔppGpp with inducible cytolysin A (ClyA in advanced stage of glioma.Materials and methods: The C6 rat glioma cells were orthotopically implanted by surgery into the caudate nucleus of rat brains. The rats were then randomly divided into the treatment group (SL + ClyA (n=12, negative control group (SL (n=12, and control group (phosphate-buffered saline [PBS] (n=12. In the treatment group, the attenuated S. typhimurium were transformed with the plasmid-encoded antitumor gene ClyA. The expression of ClyA was controlled by the TetR-regulated promoter in response to extracellular doxycycline. The plasmid also contained an imaging gene lux to allow illumination of the tumor infected by the bacteria. The rat glioma C6 cells were implanted into the caudate nucleus of all rats. The engineered S. typhimurium and respective controls were injected intravenously into the rats 21 days after initial tumor implantation. The pathological analysis of the glioma tumor was performed at 21 days and 28 days (7 days after doxycycline treatment postimplantation. All rats underwent MRI (magnetic resonance imaging and bioluminescence study at 21 days and 28 days postimplantation to detect tumor volume. The differences between the three groups in tumor volume and survival time were analyzed.Results: Advanced stage glioma  was detected at 21 days postimplantation. Bioluminescence showed that the

  1. Nuclear motility in glioma cells reveals a cell-line dependent role of various cytoskeletal components.

    Directory of Open Access Journals (Sweden)

    Alexa Kiss

    Full Text Available Nuclear migration is a general term for the movement of the nucleus towards a specific site in the cell. These movements are involved in a number of fundamental biological processes, such as fertilization, cell division, and embryonic development. Despite of its importance, the mechanism of nuclear migration is still poorly understood in mammalian cells. In order to shed light on the mechanical processes underlying nuclear movements, we adapted a micro-patterning based assay. C6 rat and U87 human glioma cells seeded on fibronectin patterns--thereby forced into a bipolar morphology--displayed oscillatory movements of the nucleus or the whole cell, respectively. We found that both the actomyosin system and microtubules are involved in the nuclear/cellular movements of both cell lines, but their contributions are cell-/migration-type specific. Dynein activity was necessary for nuclear migration of C6 cells but active myosin-II was dispensable. On the other hand, coupled nuclear and cellular movements of U87 cells were driven by actomyosin contraction. We explain these cell-line dependent effects by the intrinsic differences in the overall mechanical tension due to the various cytoskeletal elements inside the cell. Our observations showed that the movements of the nucleus and the centrosome are strongly correlated and display large variation, indicating a tight but flexible coupling between them. The data also indicate that the forces responsible for nuclear movements are not acting directly via the centrosome. Based on our observations, we propose a new model for nuclear oscillations in C6 cells in which dynein and microtubule dynamics are the main drivers of nuclear movements. This mechanism is similar to the meiotic nuclear oscillations of Schizosaccharomyces pombe and may be evolutionary conserved.

  2. Isocitrate dehydrogenase mutations in gliomas.

    Science.gov (United States)

    Waitkus, Matthew S; Diplas, Bill H; Yan, Hai

    2016-01-01

    Over the last decade, extraordinary progress has been made in elucidating the underlying genetic causes of gliomas. In 2008, our understanding of glioma genetics was revolutionized when mutations in isocitrate dehydrogenase 1 and 2 (IDH1/2) were identified in the vast majority of progressive gliomas and secondary glioblastomas (GBMs). IDH enzymes normally catalyze the decarboxylation of isocitrate to generate α-ketoglutarate (αKG), but recurrent mutations at Arg(132) of IDH1 and Arg(172) of IDH2 confer a neomorphic enzyme activity that catalyzes reduction of αKG into the putative oncometabolite D-2-hydroxyglutate (D2HG). D2HG inhibits αKG-dependent dioxygenases and is thought to create a cellular state permissive to malignant transformation by altering cellular epigenetics and blocking normal differentiation processes. Herein, we discuss the relevant literature on mechanistic studies of IDH1/2 mutations in gliomas, and we review the potential impact of IDH1/2 mutations on molecular classification and glioma therapy.

  3. Cellular factors promoting resistance to effective treatment of glioma with oncolytic myxoma virus.

    Science.gov (United States)

    Zemp, Franz J; McKenzie, Brienne A; Lun, Xueqing; Reilly, Karlyne M; McFadden, Grant; Yong, V Wee; Forsyth, Peter A

    2014-12-15

    Oncolytic virus therapy is being evaluated in clinical trials for human glioma. While it is widely assumed that the immune response of the patient to the virus infection limits the utility of the therapy, investigations into the specific cell type(s) involved in this response have been performed using nonspecific pharmacologic inhibitors or allogeneic models with compromised immunity. To identify the immune cells that participate in clearing an oncolytic infection in glioma, we used flow cytometry and immunohistochemistry to immunophenotype an orthotopic glioma model in immunocompetent mice after Myxoma virus (MYXV) administration. These studies revealed a large resident microglia and macrophage population in untreated tumors, and robust monocyte, T-, and NK cell infiltration 3 days after MYXV infection. To determine the role on the clinical utility of MYXV therapy for glioma, we used a combination of knockout mouse strains and specific immunocyte ablation techniques. Collectively, our experiments identify an important role for tumor-resident myeloid cells and overlapping roles for recruited NK and T cells in the clearance and efficacy of oncolytic MYXV from gliomas. Using a cyclophosphamide regimen to achieve lymphoablation prior and during MYXV treatment, we prevented treatment-induced peripheral immunocyte recruitment and, surprisingly, largely ablated the tumor-resident macrophage population. Virotherapy of cyclophosphamide-treated animals resulted in sustained viral infection within the glioma as well as a substantial survival advantage. This study demonstrates that resistance to MYXV virotherapy in syngeneic glioma models involves a multifaceted cellular immune response that can be overcome with cyclophosphamide-mediated lymphoablation.

  4. Convection-enhancement delivery of platinum-based drugs and Lipoplatin™ to optimize the concomitant effect with radiotherapy in F98 glioma rat model

    OpenAIRE

    SHI, MINGHAN; Fortin, David; Sanche, Léon; Paquette, Benoit

    2015-01-01

    The prognosis for patients with glioblastoma remains poor with current treatments. Although platinum based drugs are sometimes offered at relapse, their efficacy in this setting is still disputed. In this study, we use convection-enhanced delivery (CED) to deliver the platinum-based drugs (cisplatin, carboplatin, and Lipoplatin™-liposomal formulation of cisplatin) directly into the tumor of F98 glioma-bearing rats that were subsequently treated with γ radiation (15 Gy). CED increased by facto...

  5. In Vivo Imaging of Hypoxia-Inducible Factor Regulation in a Subcutaneous and Orthotopic GL261 Glioma Tumor Model Using a Reporter Gene Assay

    Directory of Open Access Journals (Sweden)

    Sandra Bürgi

    2014-11-01

    Full Text Available Intratumoral hypoxia changes the metabolism of gliomas, leading to a more aggressive phenotype with increased resistance to radio- and chemotherapy. Hypoxia triggers a signaling cascade with hypoxia-inducible factor (HIF as a key regulator. We monitored activation of the HIF pathway longitudinally in murine glioma tumors. GL261 cells, stably transfected with a luciferase reporter driven under the control of a promoter comprising the HIF target gene motive hypoxia response element, were implanted either subcutaneously or orthotopically. In vivo experiments were carried out using bioluminescence imaging. Tumors were subsequently analyzed using immunofluorescence staining for hypoxia, endothelial cells, tumor perfusion, and glucose transporter expression. Transient upregulation of the HIF signaling was observed in both subcutaneous and orthotopic gliomas. Immunofluorescence staining confirmed hypoxic regions in subcutaneous and, to a lesser extent, intracranial tumors. Subcutaneous tumors showed substantial necrosis, which might contribute to the decreased bioluminescence output observed toward the end of the experiment. Orthotopic tumors were less hypoxic than subcutaneous ones and did not develop extensive necrotic areas. Although this may be the result of the overall smaller size of orthotopic tumors, it might also reflect differences in the local environment, such as the better intrinsic vascularization of brain tissue compared to the subcutaneous tissue compartment.

  6. Laser photodetachment in liquids: C 6F -6 in tetramethylsilane

    Science.gov (United States)

    Faidas, H.; Christophorou, L. G.; McCorkle, D. L.

    1992-06-01

    The photodetachment cross section of C 6F -6 in liquid tetramethylsilane was measured as a function of the photon energy, using a new two laser photoconductivity technique. The photodetachment threshold was found to be 1.51 eV using a 3/2 power threshold law. Two maxima were observed in the photodetachment cross section at photon energies of 2.58 and 3.15 eV; the cross section value at these two maxima is ≈ 11 × 10 -18 cm 2.

  7. Molecular subtypes of glioblastoma are relevant to lower grade glioma.

    Directory of Open Access Journals (Sweden)

    Xiaowei Guan

    Full Text Available Gliomas are the most common primary malignant brain tumors in adults with great heterogeneity in histopathology and clinical course. The intent was to evaluate the relevance of known glioblastoma (GBM expression and methylation based subtypes to grade II and III gliomas (ie. lower grade gliomas.Gene expression array, single nucleotide polymorphism (SNP array and clinical data were obtained for 228 GBMs and 176 grade II/II gliomas (GII/III from the publically available Rembrandt dataset. Two additional datasets with IDH1 mutation status were utilized as validation datasets (one publicly available dataset and one newly generated dataset from MD Anderson. Unsupervised clustering was performed and compared to gene expression subtypes assigned using the Verhaak et al 840-gene classifier. The glioma-CpG Island Methylator Phenotype (G-CIMP was assigned using prediction models by Fine et al.Unsupervised clustering by gene expression aligned with the Verhaak 840-gene subtype group assignments. GII/IIIs were preferentially assigned to the proneural subtype with IDH1 mutation and G-CIMP. GBMs were evenly distributed among the four subtypes. Proneural, IDH1 mutant, G-CIMP GII/III s had significantly better survival than other molecular subtypes. Only 6% of GBMs were proneural and had either IDH1 mutation or G-CIMP but these tumors had significantly better survival than other GBMs. Copy number changes in chromosomes 1p and 19q were associated with GII/IIIs, while these changes in CDKN2A, PTEN and EGFR were more commonly associated with GBMs.GBM gene-expression and methylation based subtypes are relevant for GII/III s and associate with overall survival differences. A better understanding of the association between these subtypes and GII/IIIs could further knowledge regarding prognosis and mechanisms of glioma progression.

  8. Oncogene interactions are required for glioma development and progression as revealed by a tissue specific transgenic mouse model

    Institute of Scientific and Technical Information of China (English)

    Lynette M. Moore; Kristen M. Holmes; Gregory N. Fuller; Wei Zhang

    2011-01-01

    The aggressive and invasive nature of brain tumors has hampered progress in the design and implementation of efficacious therapies. The recent success of targeted therapies in other tumor types makes this an attractive area for research yet complicating matters is the ability of brain tumors to circumvent the targeted pathways to develop drug resistance. Effective therapies will likely need to target more than one signaling pathway or target multiple nodes within a given pathway. Key to identifying these targets is the elucidation of the driver and passenger molecules within these pathways. Animal models provide a useful tool with many advantages in the study of these pathways. These models provide a means to dissect the critical components of tumorigenesis, as well as serve as agents for preclinical testing. This review focuses on the use of the RCAS/tv-a mouse model of brain tumors and describes their unique ability to provide insight into the role of oncogene cooperation in tumor development and progression.

  9. Paediatric and adult malignant glioma

    DEFF Research Database (Denmark)

    Jones, Chris; Perryman, Lara; Hargrave, Darren

    2012-01-01

    Gliomas in children differ from their adult counterparts by their distribution of histological grade, site of presentation and rate of malignant transformation. Although rare in the paediatric population, patients with high-grade gliomas have, for the most part, a comparably dismal clinical outcome...... to older patients with morphologically similar lesions. Molecular profiling data have begun to reveal the major genetic alterations underpinning these malignant tumours in children. Indeed, the accumulation of large datasets on adult high-grade glioma has revealed key biological differences between...... the adult and paediatric disease. Furthermore, subclassifications within the childhood age group can be made depending on age at diagnosis and tumour site. However, challenges remain on how to reconcile clinical data from adult patients to tailor novel treatment strategies specifically for paediatric...

  10. Immunotherapy for malignant glioma

    Directory of Open Access Journals (Sweden)

    Carter M Suryadevara

    2015-01-01

    Full Text Available Malignant gliomas (MG are the most common type of primary malignant brain tumor. Most patients diagnosed with glioblastoma (GBM, the most common and malignant glial tumor, die within 12-15 months. Moreover, conventional treatment, which includes surgery followed by radiation and chemotherapy, can be highly toxic by causing nonspecific damage to healthy brain and other tissues. The shortcomings of standard-of-care have thus created a stimulus for the development of novel therapies that can target central nervous system (CNS-based tumors specifically and efficiently, while minimizing off-target collateral damage to normal brain. Immunotherapy represents an investigational avenue with the promise of meeting this need, already having demonstrated its potential against B-cell malignancy and solid tumors in clinical trials. T-cell engineering with tumor-specific chimeric antigen receptors (CARs is one proven approach that aims to redirect autologous patient T-cells to sites of tumor. This platform has evolved dramatically over the past two decades to include an improved construct design, and these modern CARs have only recently been translated into the clinic for brain tumors. We review here emerging immunotherapeutic platforms for the treatment of MG, focusing on the development and application of a CAR-based strategy against GBM.

  11. Human pontine glioma cells can induce murine tumors

    NARCIS (Netherlands)

    Caretti, V.; Sewing, A.C.; Lagerweij, T.; Schellen, P.; Bugiani, M.; Jansen, M.H.; Vuurden, D.G. van; Navis, A.C.; Horsman, I.; Vandertop, W.P.; Noske, D.P.; Wesseling, P.; Kaspers, G.J.L.; Nazarian, J.; Vogel, H.; Hulleman, E.; Monje, M.; Wurdinger, T.

    2014-01-01

    Diffuse intrinsic pontine glioma (DIPG), with a median survival of only 9 months, is the leading cause of pediatric brain cancer mortality. Dearth of tumor tissue for research has limited progress in this disease until recently. New experimental models for DIPG research are now emerging. To develop

  12. Frequent Nek1 overexpression in human gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun [School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai (China); Neurosurgery Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Cai, Yu, E-mail: aihaozuqiu22@163.com [School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai (China); Neurosurgery Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Liu, Pin [Med-X Research Institute, Shanghai Jiao Tong University, Shanghai (China); Zhao, Weiguo [Neurosurgery Department, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China)

    2016-08-05

    Never in mitosis A (NIMA)-related kinase 1 (Nek1) regulates cell cycle progression to mitosis. Its expression and potential functions in human gliomas have not been studied. Here, our immunohistochemistry (IHC) assay and Western blot assay results showed that Nek1 expression was significantly upregulated in fresh and paraffin-embedded human glioma tissues. Its level in normal brain tissues was low. Nek1 overexpression in human gliomas was correlated with the proliferation marker (Ki-67), tumor grade, Karnofsky performance scale (KPS) and more importantly, patients’ poor survival. Further studies showed that Nek1 expression level was also increased in multiple human glioma cell lines (U251-MG, U87-MG, U118, H4 and U373). Significantly, siRNA-mediated knockdown of Nek1 inhibited glioma cell (U87-MG/U251-MG) growth. Nek1 siRNA also sensitized U87-MG/U251-MG cells to temozolomide (TMZ), causing a profound apoptosis induction and growth inhibition. The current study indicates Nek1 might be a novel and valuable oncotarget of glioma, it is important for glioma cell growth and TMZ-resistance. - Highlights: • Nek1 is upregulated in multiple human glioma tissues and cell lines. • Nek1 overexpression correlates with glioma grades and patients’ KPS score. • Nek1 overexpression correlates with patients’ poor overall survival. • siRNA knockdown of Nek1 inhibits glioma cell growth. • siRNA knockdown of Nek1 sensitizes human glioma cells to temozolomide.

  13. Quasiclassical Trajectory Study of Collisional Energy Transfer between Highly Excited C6F6 and N2 ,O2 and Ground State C6F6

    Institute of Scientific and Technical Information of China (English)

    Jian Hua ZHOU; Shao Kun WANG; Zhi Jun YU; Hai Hui JIANG; Yue Shu GU

    2003-01-01

    Quasiclassical trajectory calculation (QCT) is used frequently for studying collisional energy transfer between highly vibrationally excited molecules and bath gases. In this paper, the QCT of the energy transfer between highly vibrationally excited C6F6 and N2 ,O2 and ground state C6F6 were performed. The results indicate that highly vibrationally excited C6F6 transferred vibrational energy to vibrational distribution of N2, O2 and ground state C6F6, so they are V-V energy transfer. Especially it is mainly V-V resonance energy transfer between excited C6F6 and ground state C6F6, excited C6F6 transfers more vibrational energy to ground state C6F6 than to N2 and O2 . The values of QCT , -〈△Evib〉of excited C6F6 are smaller than those of experiments.

  14. Neuronavigator-guided glioma surgery

    Institute of Scientific and Technical Information of China (English)

    杜固宏; 周良辅; 毛颖

    2003-01-01

    Objective To evaluate the effectiveness of neuronavigator-guided surgery for the resection of gliomas. Methods A total of 80 patients with gliomas underwent surgical treatment under the StealthStation neuronavigator to estimate the extent of the tumors. In 27 cases, the measurements of brain shifts at the dura, cortical surface and lesion margin were recorded during the operations. A technique termed "micro-catheter fence post" was used in superficial gliomas to compensate for brain shift.Results Mean fiducial error and predicted accuracy in the 80 cases were 2.03 mm±0.89 mm and 2.43 mm±0.99 mm, respectively. The shifts at the dura, cortical surface and lesion margin were 3.44 mm±2.39 mm, 7.58 mm±3.75 mm, and 6.55 mm±3.19 mm, respectively. Although neuronavigation revealed residual tumors, operations were discontinued in 5 cases of deep-seated gliomas. In the other 75 cases, total tumor removals were achieved in 62 (82.7%), and subtotal removals were achieved in 13 (17.3%). Post-operation, neurological symptoms were improved or unchanged in 68 cases (85.0%), and worsened in 12 (15.0%). No deaths occurred during the operations and post-operations. Conclusions Intraoperative brain shifts mainly contribute to the fail of spatial accuracy during neuronavigator-guided glioma surgery. The "micro-catheter fence post" technique used for glioma surgery is shown to be useful for compensating for intraoperative brain shifts. This technique, thus, contributes to an increase in total tumor removal and a decrease in surgical complications.

  15. Spondyloptosis of C6-C7: a rare case report

    Institute of Scientific and Technical Information of China (English)

    Manish Chadha; Ajay Pal Singh; Arun Pal Singh

    2010-01-01

    A 35 years old female presented to us after falling from a height. She complained of a neck pain and a complete quadriplegia and was diagnosed as having spondyloptosis of the C6-C7. Skeletal traction was performed on her. CT scan showed fractures of the C5, C6, and C7 vertebral body. The patient underwent anterior approach partial corpectomy with anterior cervical locking plate and strut grafting from ipsilateral iliac crest. Intraoperatively it was found that the disc was completely ruptured and there was a dural tear and cerebrospinal fluid leak. Her postoperative period was complicated by cerebrospinal fluid collection and posterior instrumentation was not performed due to the poor general condition. She had no neural recovery at the last follow-up. Spondyloptosis is a severe and highly unstable injury with a three column ligamentous disruption and may be complicated, as in our case, with a dural tear.Management of these cases is fraught with complications,and prognosis for neural recovery is dismal.

  16. Pediatric gliomas as neurodevelopmental disorders.

    Science.gov (United States)

    Baker, Suzanne J; Ellison, David W; Gutmann, David H

    2016-06-01

    Brain tumors represent the most common solid tumor of childhood, with gliomas comprising the largest fraction of these cancers. Several features distinguish them from their adult counterparts, including their natural history, causative genetic mutations, and brain locations. These unique properties suggest that the cellular and molecular etiologies that underlie their development and maintenance might be different from those that govern adult gliomagenesis and growth. In this review, we discuss the genetic basis for pediatric low-grade and high-grade glioma in the context of developmental neurobiology, and highlight the differences between histologically-similar tumors arising in children and adults.

  17. Differential utilization of ketone bodies by neurons and glioma cell lines: a rationale for ketogenic diet as experimental glioma therapy

    Directory of Open Access Journals (Sweden)

    Mueller-Klieser Wolfgang

    2011-07-01

    Full Text Available Abstract Background Even in the presence of oxygen, malignant cells often highly depend on glycolysis for energy generation, a phenomenon known as the Warburg effect. One strategy targeting this metabolic phenotype is glucose restriction by administration of a high-fat, low-carbohydrate (ketogenic diet. Under these conditions, ketone bodies are generated serving as an important energy source at least for non-transformed cells. Methods To investigate whether a ketogenic diet might selectively impair energy metabolism in tumor cells, we characterized in vitro effects of the principle ketone body 3-hydroxybutyrate in rat hippocampal neurons and five glioma cell lines. In vivo, a non-calorie-restricted ketogenic diet was examined in an orthotopic xenograft glioma mouse model. Results The ketone body metabolizing enzymes 3-hydroxybutyrate dehydrogenase 1 and 2 (BDH1 and 2, 3-oxoacid-CoA transferase 1 (OXCT1 and acetyl-CoA acetyltransferase 1 (ACAT1 were expressed at the mRNA and protein level in all glioma cell lines. However, no activation of the hypoxia-inducible factor-1α (HIF-1α pathway was observed in glioma cells, consistent with the absence of substantial 3-hydroxybutyrate metabolism and subsequent accumulation of succinate. Further, 3-hydroxybutyrate rescued hippocampal neurons from glucose withdrawal-induced cell death but did not protect glioma cell lines. In hypoxia, mRNA expression of OXCT1, ACAT1, BDH1 and 2 was downregulated. In vivo, the ketogenic diet led to a robust increase of blood 3-hydroxybutyrate, but did not alter blood glucose levels or improve survival. Conclusion In summary, glioma cells are incapable of compensating for glucose restriction by metabolizing ketone bodies in vitro, suggesting a potential disadvantage of tumor cells compared to normal cells under a carbohydrate-restricted ketogenic diet. Further investigations are necessary to identify co-treatment modalities, e.g. glycolysis inhibitors or antiangiogenic

  18. Differential utilization of ketone bodies by neurons and glioma cell lines: a rationale for ketogenic diet as experimental glioma therapy

    Science.gov (United States)

    2011-01-01

    Background Even in the presence of oxygen, malignant cells often highly depend on glycolysis for energy generation, a phenomenon known as the Warburg effect. One strategy targeting this metabolic phenotype is glucose restriction by administration of a high-fat, low-carbohydrate (ketogenic) diet. Under these conditions, ketone bodies are generated serving as an important energy source at least for non-transformed cells. Methods To investigate whether a ketogenic diet might selectively impair energy metabolism in tumor cells, we characterized in vitro effects of the principle ketone body 3-hydroxybutyrate in rat hippocampal neurons and five glioma cell lines. In vivo, a non-calorie-restricted ketogenic diet was examined in an orthotopic xenograft glioma mouse model. Results The ketone body metabolizing enzymes 3-hydroxybutyrate dehydrogenase 1 and 2 (BDH1 and 2), 3-oxoacid-CoA transferase 1 (OXCT1) and acetyl-CoA acetyltransferase 1 (ACAT1) were expressed at the mRNA and protein level in all glioma cell lines. However, no activation of the hypoxia-inducible factor-1α (HIF-1α) pathway was observed in glioma cells, consistent with the absence of substantial 3-hydroxybutyrate metabolism and subsequent accumulation of succinate. Further, 3-hydroxybutyrate rescued hippocampal neurons from glucose withdrawal-induced cell death but did not protect glioma cell lines. In hypoxia, mRNA expression of OXCT1, ACAT1, BDH1 and 2 was downregulated. In vivo, the ketogenic diet led to a robust increase of blood 3-hydroxybutyrate, but did not alter blood glucose levels or improve survival. Conclusion In summary, glioma cells are incapable of compensating for glucose restriction by metabolizing ketone bodies in vitro, suggesting a potential disadvantage of tumor cells compared to normal cells under a carbohydrate-restricted ketogenic diet. Further investigations are necessary to identify co-treatment modalities, e.g. glycolysis inhibitors or antiangiogenic agents that efficiently

  19. Inhibition of elongation factor-2 kinase augments the antitumor activity of Temozolomide against glioma.

    Directory of Open Access Journals (Sweden)

    Xiao-Yuan Liu

    Full Text Available BACKGROUND: Glioblastoma multiforme (GBM, the most common form of brain cancer with an average survival of less than 12 months, is a highly aggressive and fatal disease characterized by survival of glioma cells following initial treatment, invasion through the brain parenchyma and destruction of normal brain tissues, and ultimately resistance to current treatments. Temozolomide (TMZ is commonly used chemotherapy for treatment of primary and recurrent high-grade gliomas. Nevertheless, the therapeutic outcome of TMZ is often unsatisfactory. In this study, we sought to determine whether eEF-2 kinase affected the sensitivity of glioma cells to treatment with TMZ. METHODOLOGY/PRINCIPAL FINDINGS: Using RNA interference approach, a small molecule inhibitor of eEF-2 kinase, and in vitro and in vivo glioma models, we observed that inhibition of eEF-2 kinase could enhance sensitivity of glioma cells to TMZ, and that this sensitizing effect was associated with blockade of autophagy and augmentation of apoptosis caused by TMZ. CONCLUSIONS/SIGNIFICANCE: These findings demonstrated that targeting eEF-2 kinase can enhance the anti-glioma activity of TMZ, and inhibitors of this kinase may be exploited as chemo-sensitizers for TMZ in treatment of malignant glioma.

  20. Pharmacokinetics and the bystander effect in CD::UPRT/5-FC bi-gene therapy of glioma

    Institute of Scientific and Technical Information of China (English)

    SHI De-zhi; HU Wei-xing; LI Li-xin; CHEN Gong; WEI Dong; GU Pei-yuan

    2009-01-01

    Background Cytosine deaminase (CD) converts 5-fluorocytosine (5-FC) to 5-fluorouracil (5-FU) in CD/5-FC gene therapy, 5-FU will be mostly converted into nontoxic β-alanine without uracil phosphoribosyltransferase (UPRT). UPRT catalyzes the conversion of 5-FU to 5-fluorouridine monophosphate, which directly kills CD::UPRT-expressing ceils and surrounding cells via the bystander effect. But the pharmacokinetics and the bystander effect of CD::UPRT/5-FC has not been verified in vivo and in vitro. Before the CD::UPRT/5-FC bi-gene therapy system is used in clinical trial, it is essential to monitor the transgene expression and function in vivo. Thus, we developed a preclinical tumor model to investigate the feasibility of using 19F-magnetic resonance spectroscopy (19F-MRS) and optical imaging to measure non-invasive CD and UPRT expression and its bystander effect.Methods C6 and C6-CD::UPRT cells were cultured with 5-FC. The medium, cells and their mixture were analyzed by 19F-MRS. Rats with intracranial xenografted encephalic C6-CD::UPRT glioma were injected intraperitoneally with 5-FC and their 19F-MRS spectra recorded. Then the pharmacokinetics of 5-FC was proved. Mixtures of C6 and C6-CD::UPRT cells at different ratios were cultured with 5-FC and the cytotoxic efficacy and survival rate of cells recorded. To determine the mechanism of the bystander effect, the culture media from cell comprising 25% and 75% C6-CD::UPRT cells were examined by19F-MRS. A comparative study of mean was performed using analysis of variance (ANOVA). Results 19F-MRS on samples from C6-CD::UPRT cells cultured with 5-FC showed three broad resonance signals corresponding to 5-FC, 5-FU and fluorinated nucleotides (F-Nuctd). For the C6 mixture, only the 5-FC peak was detected. In vivo serial 19F-MRS spectra showed a strong 5-FC peak and a weak 5-FU peak at 20 minutes after 5-FC injection. The 5-FU concentration reached a maximum at about 50 minutes. The F-Nuctd signal appeared after about I hour

  1. Superconductivity in the Graphite Intercalation Compound BaC(6).

    Science.gov (United States)

    Heguri, Satoshi; Kawade, Naoya; Fujisawa, Takumi; Yamaguchi, Akira; Sumiyama, Akihiko; Tanigaki, Katsumi; Kobayashi, Mototada

    2015-06-19

    Among many two-dimensional (2D) high T(C) superconductors, graphite intercalation compounds (GICs) are the most famous intercalation family, which are classified as typical electron-phonon mediated superconductors. We show unambiguous experimental facts that BaC(6), the superconductivity of which has been missing for many years so far among various alkaline earth metal (Ca, Sr, and Ba) intercalted GICs, exhibits superconductivity at T(C)=65  mK. By adding this finding as the additional experimental point, a complete figure displaying the relationship between T(C) and interlayer distance (d) for GICs is now provided, and their possible superconducting mechanisms raised so far are revisited. The present study settles a long-running debate between theories and experiments on the superconductivity in the first stage GICs.

  2. Depot delivery of dexamethasone and cediranib for the treatment of brain tumor associated edema in an intracranial rat glioma model.

    Science.gov (United States)

    Ong, Qunya; Hochberg, Fred H; Cima, Michael J

    2015-11-10

    Treatments of brain tumor associated edema with systemically delivered dexamethasone, the standard of care, and cediranib, a novel anti-edema agent, are associated with systemic toxicities in brain tumor patients. A tunable, reservoir-based drug delivery device was developed to investigate the effects of delivering dexamethasone and cediranib locally in the brain in an intracranial 9L gliosarcoma rat model. Reproducible, sustained releases of both dexamethasone and solid dispersion of cediranib in polyvinylpyrrolidone (AZD/PVP) from these devices were achieved. The water-soluble AZD/PVP, which exhibited similar bioactivity as cediranib, was developed to enhance the release of cediranib from the device. Local and systemic administration of both dexamethasone and cediranib was equally efficacious in alleviating edema but had no effect on tumor growth. Edema reduction led to modest but significant improvement in survival. Local delivery of dexamethasone prevented dexamethasone-induced weight loss, an adverse effect seen in animals treated with systemic dexamethasone. Local deliveries of dexamethasone and cediranib via these devices used only 2.36% and 0.21% of the systemic doses respectively, but achieved similar efficacy as systemic drug deliveries without the side effects associated with systemic administration. Other therapeutic agents targeting brain tumor can be delivered locally in the brain to provide similar improved treatment outcomes. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. VapC6, a ribonucleolytic toxin regulates thermophilicity in the crenarchaeote Sulfolobus solfataricus.

    Science.gov (United States)

    Maezato, Yukari; Daugherty, Amanda; Dana, Karl; Soo, Edith; Cooper, Charlotte; Tachdjian, Sabrina; Kelly, Robert M; Blum, Paul

    2011-07-01

    The phylum Crenarchaeota includes hyperthermophilic micro-organisms subjected to dynamic thermal conditions. Previous transcriptomic studies of Sulfolobus solfataricus identified vapBC6 as a heat-shock (HS)-inducible member of the Vap toxin-antitoxin gene family. In this study, the inactivation of the vapBC6 operon by targeted gene disruption produced two recessive phenotypes related to fitness, HS sensitivity and a heat-dependent reduction in the rate of growth. In-frame vapBC6 deletion mutants were analyzed to examine the respective roles of each protein. Since vapB6 transcript abundance was elevated in the vapC6 deletion, the VapC6 toxin appears to regulate abundance of its cognate antitoxin. In contrast, vapC6 transcript abundance was reduced in the vapB6 deletion. A putative intergenic terminator may underlie these observations by coordinating vapBC6 expression. As predicted by structural modeling, recombinant VapC6 produced using chaperone cosynthesis exhibited heat-dependent ribonucleolytic activity toward S. solfataricus total RNA. This activity could be blocked by addition of preheated recombinant VapB6. In vivo transcript targets were identified by assessing the relative expression of genes that naturally respond to thermal stress in VapBC6-deficient cells. Preferential increases were observed for dppB-1 and tetR, and preferential decreases were observed for rpoD and eIF2 gamma. Specific VapC6 ribonucleolytic action could also be demonstrated in vitro toward RNAs whose expression increased in the VapBC6-deficient strain during heat shock. These findings provide a biochemical mechanism and identify cellular targets underlying VapBC6-mediated control over microbial growth and survival at temperature extremes.

  4. Ets Factors Regulate Neural Stem Cell Depletion and Gliogenesis in Ras Pathway Glioma.

    Science.gov (United States)

    Breunig, Joshua J; Levy, Rachelle; Antonuk, C Danielle; Molina, Jessica; Dutra-Clarke, Marina; Park, Hannah; Akhtar, Aslam Abbasi; Kim, Gi Bum; Hu, Xin; Bannykh, Serguei I; Verhaak, Roel G W; Danielpour, Moise

    2015-07-14

    As the list of putative driver mutations in glioma grows, we are just beginning to elucidate the effects of dysregulated developmental signaling pathways on the transformation of neural cells. We have employed a postnatal, mosaic, autochthonous glioma model that captures the first hours and days of gliomagenesis in more resolution than conventional genetically engineered mouse models of cancer. We provide evidence that disruption of the Nf1-Ras pathway in the ventricular zone at multiple signaling nodes uniformly results in rapid neural stem cell depletion, progenitor hyperproliferation, and gliogenic lineage restriction. Abolishing Ets subfamily activity, which is upregulated downstream of Ras, rescues these phenotypes and blocks glioma initiation. Thus, the Nf1-Ras-Ets axis might be one of the select molecular pathways that are perturbed for initiation and maintenance in glioma.

  5. The transcriptional coactivator TAZ regulates mesenchymal differentiation in malignant glioma.

    Science.gov (United States)

    Bhat, Krishna P L; Salazar, Katrina L; Balasubramaniyan, Veerakumar; Wani, Khalida; Heathcock, Lindsey; Hollingsworth, Faith; James, Johanna D; Gumin, Joy; Diefes, Kristin L; Kim, Se Hoon; Turski, Alice; Azodi, Yasaman; Yang, Yuhui; Doucette, Tiffany; Colman, Howard; Sulman, Erik P; Lang, Frederick F; Rao, Ganesh; Copray, Sjef; Vaillant, Brian D; Aldape, Kenneth D

    2011-12-15

    Recent molecular classification of glioblastoma (GBM) has shown that patients with a mesenchymal (MES) gene expression signature exhibit poor overall survival and treatment resistance. Using regulatory network analysis of available expression microarray data sets of GBM, including The Cancer Genome Atlas (TCGA), we identified the transcriptional coactivator with PDZ-binding motif (TAZ), to be highly associated with the MES network. TAZ expression was lower in proneural (PN) GBMs and lower-grade gliomas, which correlated with CpG island hypermethylation of the TAZ promoter compared with MES GBMs. Silencing of TAZ in MES glioma stem cells (GSCs) decreased expression of MES markers, invasion, self-renewal, and tumor formation. Conversely, overexpression of TAZ in PN GSCs as well as murine neural stem cells (NSCs) induced MES marker expression and aberrant osteoblastic and chondrocytic differentiation in a TEAD-dependent fashion. Using chromatin immunoprecipitation (ChIP), we show that TAZ is directly recruited to a majority of MES gene promoters in a complex with TEAD2. The coexpression of TAZ, but not a mutated form of TAZ that lacks TEAD binding, with platelet-derived growth factor-B (PDGF-B) resulted in high-grade tumors with MES features in a murine model of glioma. Our studies uncover a direct role for TAZ and TEAD in driving the MES differentiation of malignant glioma.

  6. Senescence from glioma stem cell differentiation promotes tumor growth

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, Rie [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Okabe, Sachiko; Migita, Toshiro [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nakano, Ichiro [Department of Neurosurgery, Comprehensive Cancer Center, University of Alabama at Birmingham, 1824 6th Avenue South, Birmingham, AL 35233 (United States); Seimiya, Hiroyuki, E-mail: hseimiya@jfcr.or.jp [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan)

    2016-02-05

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  7. Notch Signaling Enhances Nestin Expression in Gliomas

    Directory of Open Access Journals (Sweden)

    Alan H. Shih

    2006-12-01

    Full Text Available Recent findings suggest that Notch signaling is active in brain tumors and stem cells, and that stem cells or cells with progenitor characteristics contribute to brain tumor formation. These stem cells are marked by expression of several markers, including nestin, an intermediate filament protein. We have studied how the Notch signaling pathway affects nestin expression in brain tumors. We find that Notch receptors and ligands are expressed in vitro and in human samples of glioblastomas, the highest grade of malignant gliomas. In culture, Notch activity activates the nestin promoter. Activation of the Notch pathway also occurs in a glioblastoma multiforme mouse model induced by Kras, with translational regulation playing a role in Notch expression. Combined activation of Notch and Kras in wild-type nestin-expressing cells leads to their expansion within the subventricular zone and retention of proliferation and nestin expression. However, activation of Notch alone is unable to induce this cellular expansion. These data suggest that Notch may have a contributing role in the stem-like character of glioma cells.

  8. MicroRNA in Human Glioma

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mengfeng, E-mail: limf@mail.sysu.edu.cn [Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou 510080 (China); Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Li, Jun [Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou 510080 (China); Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Liu, Lei; Li, Wei [Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou 510080 (China); Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Yang, Yi [Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou 510080 (China); Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080 (China); Yuan, Jie [Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou 510080 (China); Key Laboratory of Functional Molecules from Oceanic Microorganisms (Sun Yat-sen University), Department of Education of Guangdong Province, Guangzhou 510080 (China)

    2013-10-23

    Glioma represents a serious health problem worldwide. Despite advances in surgery, radiotherapy, chemotherapy, and targeting therapy, the disease remains one of the most lethal malignancies in humans, and new approaches to improvement of the efficacy of anti-glioma treatments are urgently needed. Thus, new therapeutic targets and tools should be developed based on a better understanding of the molecular pathogenesis of glioma. In this context, microRNAs (miRNAs), a class of small, non-coding RNAs, play a pivotal role in the development of the malignant phenotype of glioma cells, including cell survival, proliferation, differentiation, tumor angiogenesis, and stem cell generation. This review will discuss the biological functions of miRNAs in human glioma and their implications in improving clinical diagnosis, prediction of prognosis, and anti-glioma therapy.

  9. Mobile phone use and glioma risk: A systematic review and meta-analysis.

    Science.gov (United States)

    Yang, Ming; Guo, WenWen; Yang, ChunSheng; Tang, JianQin; Huang, Qian; Feng, ShouXin; Jiang, AiJun; Xu, XiFeng; Jiang, Guan

    2017-01-01

    Many studies have previously investigated the potential association between mobile phone use and the risk of glioma. However, results from these individual studies are inconclusive and controversial. The objective of our study was to investigate the potential association between mobile phone use and subsequent glioma risk using meta-analysis. We performed a systematic search of the Science Citation Index Embase and PubMed databases for studies reporting relevant data on mobile phone use and glioma in 1980-2016. The data were extracted and measured in terms of the odds ratio (OR) and 95% confidence interval (CI) using the random effects model. Subgroup analyses were also carried out. This meta-analysis eventually included 11 studies comprising a total 6028 cases and 11488 controls. There was a significant positive association between long-term mobile phone use (minimum, 10 years) and glioma (OR = 1.44, 95% CI = 1.08-1.91). And there was a significant positive association between long-term ipsilateral mobile phone use and the risk of glioma (OR = 1.46, 95% CI = 1.12-1.92). Long-term mobile phone use was associated with 2.22 times greater odds of low-grade glioma occurrence (OR = 2.22, 95% CI = 1.69-2.92). Mobile phone use of any duration was not associated with the odds of high-grade glioma (OR = 0.81, 95% CI = 0.72-0.92). Contralateral mobile phone use was not associated with glioma regardless of the duration of use. Similarly, this association was not observed when the analysis was limited to high-grade glioma. Our results suggest that long-term mobile phone use may be associated with an increased risk of glioma. There was also an association between mobile phone use and low-grade glioma in the regular use or long-term use subgroups. However, current evidence is of poor quality and limited quantity. It is therefore necessary to conduct large sample, high quality research or better characterization of any potential association between long-term ipsilateral mobile

  10. Effects of antihistamine and anti-inflammatory medication use on risk of specific glioma histologies

    OpenAIRE

    Scheurer, Michael E.; Amirian, E. Susan; Davlin, Stacy L.; Rice, Terri; Wrensch, Margaret; Melissa L. Bondy

    2011-01-01

    Several studies have shown a decrease in glioma risk associated with a personal history of allergic conditions and the medications used to treat the symptoms. However, few studies have been able to examine risk within histological subgroups of glioma. Case-control data from M. D. Anderson Cancer Center and University of California, San Francisco were pooled to conduct the analysis stratified by histological subtype. A risk prediction model considering inflammation-related variables and antihi...

  11. Enhancement of 5-aminolevulinic acid-based fluorescence detection of side population-defined glioma stem cells by iron chelation

    Science.gov (United States)

    Wang, Wenqian; Tabu, Kouichi; Hagiya, Yuichiro; Sugiyama, Yuta; Kokubu, Yasuhiro; Murota, Yoshitaka; Ogura, Shun-ichiro; Taga, Tetsuya

    2017-01-01

    Cancer stem cells (CSCs) are dominantly responsible for tumor progression and chemo/radio-resistance, resulting in tumor recurrence. 5-aminolevulinic acid (ALA) is metabolized to fluorescent protoporphyrin IX (PpIX) specifically in tumor cells, and therefore clinically used as a reagent for photodynamic diagnosis (PDD) and therapy (PDT) of cancers including gliomas. However, it remains to be clarified whether this method could be effective for CSC detection. Here, using flow cytometry-based analysis, we show that side population (SP)-defined C6 glioma CSCs (GSCs) displayed much less 5-ALA-derived PpIX fluorescence than non-GSCs. Among the C6 GSCs, cells with ultralow PpIX fluorescence exhibited dramatically higher tumorigenicity when transplanted into the immune-deficient mouse brain. We further demonstrated that the low PpIX accumulation in the C6 GSCs was enhanced by deferoxamine (DFO)-mediated iron chelation, not by reserpine-mediated inhibition of PpIX-effluxing ABCG2. Finally, we found that the expression level of the gene for heme oxygenase-1 (HO-1), a heme degradation enzyme, was high in C6 GSCs, which was further up-regulated when treated with 5-ALA. Our results provide important new insights into 5-ALA-based PDD of gliomas, particularly photodetection of SP-defined GSCs by iron chelation based on their ALA-PpIX-Heme metabolism. PMID:28169355

  12. The Glioma International Case-Control Study

    DEFF Research Database (Denmark)

    Amirian, E. Susan; Armstrong, Georgina N; Zhou, Renke

    2016-01-01

    Decades of research have established only a few etiological factors for glioma, which is a rare and highly fatal brain cancer. Common methodological challenges among glioma studies include small sample sizes, heterogeneity of tumor subtypes, and retrospective exposure assessment. Here, we briefly...... describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen...

  13. 全程无缝隙护理模式在胶质瘤术后患者中的应用%Aapplication of seamless nursing model to postoperative patients with gliomaRen

    Institute of Scientific and Technical Information of China (English)

    任琳; 任学芳; 郎黎薇; 殷志雯

    2013-01-01

    目的 探讨全程无缝隙护理模式在胶质瘤患者中的应用效果.方法 选择手术联合放化疗的Ⅲ、Ⅳ级胶质瘤患者200例,随机分为观察组与对照组各100例.对照组采用胶质瘤手术及放化疗护理常规护理.观察组实施全程无缝隙的模式护理,即在常规护理的基础上,于患者放化疗期间发放专病健康教育手册、建立电话短信平台、上门访视、举办病友沙龙等.分别于放疗、化疗疗程结束时测定两组患者的癌因性疲乏与生活质量.结果 观察组癌因性疲乏得分显著低于对照组,生活质量评分显著优于对照组(均P<0.01).结论 全程无缝隙护理模式有助于缓解胶质瘤患者在放化疗期间的身心疲劳,提高其生活质量.%Objective To explore the effect of seamless nursing model on glioma patients. Methods We chose 200 patients with grade Ⅲ /Ⅳ gliomas who received a combination of surgery, radiation therapy, and chemotherapy were randomly divided into an observation group and a control group, with 100 cases in each group. The control group were given routine nursing care. Beside routine nursing care, the observation group additionally received seamless nursing care: we provided disease-oriented health education manual, set up telephone and text message platform, paid visits, and held ward mate salons, etc. At the end of radiation and chemotherapy, we measured the level of cancer-related fatigue and quality of life for the 2 groups. Results The level of cancer-related fatigue were significantly lower, and the quality of life were significantly higher in the observation group than in the control group(P<0. 01 for both). Conclusion Seamless nursing care helps to ease physical and mental fatigue of glioma patients, and therefore improves their quality of life.

  14. Influence of 12C6+ ion irradiation on mutant avermitilis

    Science.gov (United States)

    Wang, Shu-Yang; Chen, Ji-Hong; Li, Wen-Jian; Liang, Jian-Ping; Bo, Yong-Heng; Ma, Xiao-Qi; Liu, Jing

    2012-11-01

    The effects of 12C+6 ion irradiation on colony morphology and mycelia morphology, as well as on mutation rate have been studied in the B1a high-product strains (ZJAV-Y1-203) mutated by heavy ion irradiation and compared with that in the original strain (ZJAV-A-1). After irradiating the rate of a straw hat colony type having a high ability of producing B1a in ZJAV-Y1-203 strains was higher than that found in ZJAV-A-1 strains. When strains were cultured in a liquid medium for 24 hours, the mycelium becoming thinner could be observed in all of the irradiated ZJAV- Y1-203 groups, but only in the ZJAV-A-1 groups irradiated at the dose of 50 Gy or more. The early growth of mycelium was inhibited in the ZJAV- Y1-203 group irradiated with a high dose. The highest positive mutation rate (23.5%) of ZJAV - Y1 - 203 was reached at the lower dose of 30 Gy while the highest positive mutation rate of 34.2% in ZJAV-A-1 appeared at 50 Gy. These results indicate that the effects of heavy ion irradiation still exist even in the mutated Streptomyces avermitilis, and only the dose is lower and the effects not so strong compared with the one that is first irradiated with optimized heavy ion doses. This is evidence of the one directional mutation being controlled by many more factors in a organism.

  15. Influence of 12C6+ ion irradiation on mutant avermitilis

    Institute of Scientific and Technical Information of China (English)

    WANG Shu-Yang; CHEN Ji-Hong; LI Wen-Jian; LIANG Jian-Ping; BO Yong-Heng; MA Xiao-Qi; LIU Jing

    2012-01-01

    The effects of 12C+6ion irradiation on colony morphology and mycelia morphology,as well as on mutation rate have been studied in the Bla high-product strains (ZJAV-Y1-203) mutated by heavy ion irradiation and compared with that in the original strain (ZJAV-A-1).After irradiating the rate of a straw hat colony type having a high ability of producing B1a in ZJAV-Y1-203 strains was higher than that found in ZJAV-A-1 strains.When strains were cultured in a liquid medium for 24 hours,the mycelium becoming thinner could be observed in all of the irradiated ZJAV-Y1-203 groups,but only in the ZJAV-A-1 groups irradiated at the dose of 50 Gy or more.The early growth of mycelium was inhibited in the ZJAV-Y1-203 group irradiated with a high dose.The highest positive mutation rate (23.5%) of ZJAV-Y1-203 was reached at the lower dose of 30 Gy while the highest positive mutation rate of 34.2% in ZJAV-A-1 appeared at 50 Gy.These results indicate that the effects of heavy ion irradiation still exist even in the mutated Streptomyces avermitilis,and only the dose is lower and the effects not so strong compared with the one that is first irradiated with optimized heavy ion doses.This is evidence of the one directional mutation being controlled by many more factors in a organism.

  16. Functionally-defined Therapeutic Targets in Diffuse Intrinsic Pontine Glioma

    Science.gov (United States)

    Grasso, Catherine S.; Tang, Yujie; Truffaux, Nathalene; Berlow, Noah E.; Liu, Lining; Debily, Marie-Anne; Quist, Michael J.; Davis, Lara E.; Huang, Elaine C.; Woo, Pamelyn J; Ponnuswami, Anitha; Chen, Spenser; Johung, Tessa B.; Sun, Wenchao; Kogiso, Mari; Du, Yuchen; Lin, Qi; Huang, Yulun; Hütt-Cabezas, Marianne; Warren, Katherine E.; Dret, Ludivine Le; Meltzer, Paul S.; Mao, Hua; Quezado, Martha; van Vuurden, Dannis G.; Abraham, Jinu; Fouladi, Maryam; Svalina, Matthew N.; Wang, Nicholas; Hawkins, Cynthia; Nazarian, Javad; Alonso, Marta M.; Raabe, Eric; Hulleman, Esther; Spellman, Paul T.; Li, Xiao-Nan; Keller, Charles; Pal, Ranadip; Grill, Jacques; Monje, Michelle

    2015-01-01

    Diffuse Intrinsic Pontine Glioma (DIPG) is a fatal childhood cancer. We performed a chemical screen in patient-derived DIPG cultures along with RNAseq analyses and integrated computational modeling to identify potentially effective therapeutic strategies. The multi-histone deacetylase inhibitor panobinostat demonstrated efficacy in vitro and in DIPG orthotopic xenograft models. Combination testing of panobinostat with histone demethylase inhibitor GSKJ4 revealed synergy. Together, these data suggest a promising therapeutic strategy for DIPG. PMID:25939062

  17. Analysis on Biomechanical Characteristics of Post-operational Vertebral C5-C6 Segments

    Directory of Open Access Journals (Sweden)

    Heqiang Tian

    2016-03-01

    Full Text Available Both anterior cervical decompression and fusion (ACDF and artificial cervical disc replacement (ACDR have obvious advantages in the treatment of cervical spondylosis. To analyze the operation results, it is absolutely necessary to study the biomechanics of the movement range of post-operational vertebral C5-C6 segments, especially the biomechanical characteristics in cervical tissues in actual movements. In this study, using the human vertebral 3D graph gained by imaging diagnosis (CT, a vertebral solid model is established by the 3D reconstruction algorithm and reverse engineering technology. After that, with cervical soft tissue structure added to the solid model and set with a joint contact mechanism, a finite element model with a complete, accurate cervical C5-C6 kinematic unit is constructed, based on relevant physiological anatomical knowledge. This model includes vertebral segments, an intervertebral disc, ligament and zygopophysis in the cervical C5-C6 kinematic unit. In the created vertebral finite element model, the model is amended, referring to ACDF and ACDR, and the load and constraint are applied to a normal group, a fusion group and a displacement group, so as to analyze the biomechanical characteristics of the cervical vertebra after ACDF and ACDR. By comparing the finite element simulation results of different surgeries, this paper is intended to evaluate the functions and biomechanical behaviors of the post-operational vertebra, and explore the influence of the operation on the biomechanical stability of the cervical vertebra. This will provide theoretical guidance for implementation and optimization of ACDF and ACDR.

  18. Tumor Metabolism of Malignant Gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Ru, Peng; Williams, Terence M.; Chakravarti, Arnab; Guo, Deliang, E-mail: deliang.guo@osumc.edu [Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center & Arthur G James Cancer Hospital, Columbus, OH 43012 (United States)

    2013-11-08

    Constitutively activated oncogenic signaling via genetic mutations such as in the EGFR/PI3K/Akt and Ras/RAF/MEK pathways has been recognized as a major driver for tumorigenesis in most cancers. Recent insights into tumor metabolism have further revealed that oncogenic signaling pathways directly promote metabolic reprogramming to upregulate biosynthesis of lipids, carbohydrates, protein, DNA and RNA, leading to enhanced growth of human tumors. Therefore, targeting cell metabolism has become a novel direction for drug development in oncology. In malignant gliomas, metabolism pathways of glucose, glutamine and lipid are significantly reprogrammed. Moreover, molecular mechanisms causing these metabolic changes are just starting to be unraveled. In this review, we will summarize recent studies revealing critical gene alterations that lead to metabolic changes in malignant gliomas, and also discuss promising therapeutic strategies via targeting the key players in metabolic regulation.

  19. Tumor Metabolism of Malignant Gliomas

    Directory of Open Access Journals (Sweden)

    Deliang Guo

    2013-11-01

    Full Text Available Constitutively activated oncogenic signaling via genetic mutations such as in the EGFR/PI3K/Akt and Ras/RAF/MEK pathways has been recognized as a major driver for tumorigenesis in most cancers. Recent insights into tumor metabolism have further revealed that oncogenic signaling pathways directly promote metabolic reprogramming to upregulate biosynthesis of lipids, carbohydrates, protein, DNA and RNA, leading to enhanced growth of human tumors. Therefore, targeting cell metabolism has become a novel direction for drug development in oncology. In malignant gliomas, metabolism pathways of glucose, glutamine and lipid are significantly reprogrammed. Moreover, molecular mechanisms causing these metabolic changes are just starting to be unraveled. In this review, we will summarize recent studies revealing critical gene alterations that lead to metabolic changes in malignant gliomas, and also discuss promising therapeutic strategies via targeting the key players in metabolic regulation.

  20. Insulin suppresses MPP(+)-induced neurotoxicity by targeting integrins and syndecans in C6 astrocytes.

    Science.gov (United States)

    Ramalingam, Mahesh; Cheng, Mi Hyun; Kim, Sung-Jin

    2017-08-30

    Parkinson's disease (PD) is the second most common neurodegenerative disease in the elderly. In central nervous system, astrocytes regulates neuronal function via the modulation of synaptic transmission and plasticity, secretion of growth factors, uptake of neurotransmitters and regulation of extracellular ion concentrations and metabolic support of neurons. Therefore, C6 astroglial cells have been used to study the in vitro PD model induced by 1-methyl-4-phenyl pyridinium (MPP(+)). In this study, pre-treatment of insulin inhibited MPP(+)-induced cell membrane damages on LDH and NO releases, which also inhibited the iNOS and Cox-2 levels. Insulin also up-regulated the PI3K and p-GSK-3β protein expressions in C6 cells. In addition, MPP(+) and/or insulin enhanced the autophagy by increasing LC3-I to LC3-II conversion. Furthermore, MPP(+)-induced toxicity diminished the integrin β3, αV, syndecan-1 and -3. Insulin pre-treatment enhanced the phosphorylation of integrin-linked kinase and further induced the integrin and syndecan molecules. These findings suggest that insulin prevents MPP(+)-induced toxicity through activation of PI3K, p-GSK-3β, autophagy, integrins and syndecans pathways in C6 glial cells.

  1. Insights into the relationship between the haem-binding pocket and the redox potential of c6 cytochromes: four atomic resolution structures of c6 and c6-like proteins from Synechococcus sp. PCC 7002.

    Science.gov (United States)

    Bialek, Wojciech; Krzywda, Szymon; Zatwarnicki, Pawel; Jaskolski, Mariusz; Kolesinski, Piotr; Szczepaniak, Andrzej

    2014-11-01

    The structure of cytochrome c6C from the mesophilic cyanobacterium Synechococcus sp. PCC 7002 has been determined at 1.03 Å resolution. This is the first structural report on the recently discovered cyanobacterial cytochrome c6-like proteins found in marine and nitrogen-fixing cyanobacteria. Despite high similarity in the overall three-dimensional fold between cytochromes c6 and c6C, the latter shows saliently different electrostatic properties in terms of surface charge distribution and dipole moments. Its midpoint redox potential is less than half of the value for typical c6 cytochromes and results mainly from the substitution of one residue in the haem pocket. Here, high-resolution crystal structures of mutants of both cytochromes c6 and c6C are presented, and the impact of the mutation of specific residues in the haem-binding pocket on the redox potential is discussed. These findings contribute to the elucidation of the structure-function relationship of c6-like cytochromes.

  2. Disruption of NF-κB signaling by fluoxetine attenuates MGMT expression in glioma cells

    Directory of Open Access Journals (Sweden)

    Song T

    2015-08-01

    Full Text Available Tao Song,1 Hui Li,2 Zhiliang Tian,3 Chaojiu Xu,4 Jingfang Liu,1 Yong Guo1 1Department of Neurosurgery, Xiangya Hospital, Central South University, 2Department of Immunology and Microbiology, Medical School of Jishou University, 3Department of Neurosurgery, 4Department of Oncology, The Hospital of Xiangxi Autonomous Prefecture, Jishou, People’s Republic of China Background: Resistance to temozolomide (TMZ in glioma is modulated by the DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT. This study aimed to examine the effects of fluoxetine (FLT on MGMT expression in glioma cells and to investigate its underlying mechanisms.Materials and methods: Expression of MGMT, GluR1, or IκB kinase β (IKKβ was attenuated using short hairpin RNA-mediated gene knockdown. The 3-(4,5-dimethylthiazol -2-yl-2,5-diphenyltetrazolium bromide (MTT assay was used to evaluate the growth inhibition induced by FLT or TMZ. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL was conducted to detect apoptotic cells. Western blotting was conducted to analyze the protein expression of MGMT, IKKβ, and NF-κB/p65 following FLT treatment. The murine subcutaneous xenograft model was used to evaluate the combinational effect of TMZ and FLT.Results: FLT markedly reduced MGMT expression in glioma cells, which was independent of GluR1 receptor function. Further, FLT disrupted NF-κB/p65 signaling in glioma cells and consequently attenuated NF-κB/p65 activity in regulating MGMT expression. Importantly, FLT sensitized MGMT-expressing glioma cells to TMZ, as FLT enhanced TMZ’s ability to impair the in vitro tumorigenic potential and to induce apoptosis in glioma cells. Knockdown of MGMT or IKKβ expression abolished the synergistic effect of FLT with TMZ in glioma cells, which suggested that FLT might sensitize glioma cells to TMZ through down-regulation of MGMT expression. Consistently, TMZ combined with FLT markedly attenuated NF

  3. Down-regulation of neogenin accelerated glioma progression through promoter Methylation and its overexpression in SHG-44 Induced Apoptosis.

    Directory of Open Access Journals (Sweden)

    Xinmin Wu

    Full Text Available BACKGROUND: Dependence receptors have been proved to act as tumor suppressors in tumorigenesis. Neogenin, a DCC homologue, well known for its fundamental role in axon guidance and cellular differentiation, is also a dependence receptor functioning to control apoptosis. However, loss of neogenin has been reported in several kinds of cancers, but its role in glioma remains to be further investigated. METHODOLOGY/PRINCIPAL FINDINGS: Western blot analysis showed that neogenin level was lower in glioma tissues than in their matching surrounding non-neoplastic tissues (n = 13, p<0.01. By immunohistochemical analysis of 69 primary and 16 paired initial and recurrent glioma sections, we found that the loss of neogenin did not only correlate negatively with glioma malignancy (n = 69, p<0.01, but also glioma recurrence (n = 16, p<0.05. Kaplan-Meier plot and Cox proportional hazards modelling showed that over-expressive neogenin could prolong the tumor latency (n = 69, p<0.001, 1187.6 ± 162.6 days versus 687.4 ± 254.2 days and restrain high-grade glioma development (n = 69, p<0.01, HR: 0.264, 95% CI: 0.102 to 0.687. By Methylation specific polymerase chain reaction (MSP, we reported that neogenin promoter was methylated in 31.0% (9/29 gliomas, but absent in 3 kinds of glioma cell lines. Interestingly, the prevalence of methylation in high-grade gliomas was higher than low-grade gliomas and non-neoplastic brain tissues (n = 33, p<0.05 and overall methylation rate increased as glioma malignancy advanced. Furthermore, when cells were over-expressed by neogenin, the apoptotic rate in SHG-44 was increased to 39.7% compared with 8.1% in the blank control (p<0.01 and 9.3% in the negative control (p<0.01. CONCLUSIONS/SIGNIFICANCE: These observations recapitulated the proposed role of neogenin as a tumor suppressor in gliomas and we suggest its down-regulation owing to promoter methylation is a selective advantage for glioma genesis, progression and recurrence

  4. Concurrent Chemotherapy of Malignant Glioma in Rats by Using Multidrug-Loaded Biodegradable Nanofibrous Membranes

    Science.gov (United States)

    Tseng, Yuan-Yun; Huang, Yin-Chen; Yang, Tao-Chieh; Yang, Shun-Tai; Liu, Shou-Cheng; Chang, Tzu-Min; Kau, Yi-Chuan; Liu, Shih-Jung

    2016-07-01

    Glioblastoma multiforme has a poor prognosis and is highly chemoresistant. In this study, we implanted biodegradable 1,3-bis[2-chloroethyl]-1-nitroso-urea-, irinotecan-, and cisplatin-eluting poly[(d,l)-lactide-co-glycolide] (BIC/PLGA) and virgin nanofibrous membranes on the brain surface of C6 glioma-bearing rats in concurrent and virgin groups, respectively. The concentrations of all applied drugs were significantly higher in the brain than in the blood for more than 8 weeks in all studied rats. Tumor growth was more rapid in the vehicle-treated group, and tumor volumes were significantly higher in the vehicle-treated group. Moreover, the average survival time was significantly shorter in the vehicle-treated group (P = 0.026), and the BIC/PLGA nanofibrous membranes significantly reduced the risk of mortality (P < 0.001). Furthermore, the results suggested that the BIC/PLGA nanofibers reduced the malignancy of C6 glioma. The experimental findings indicate that the multianticancer drug (i.e., BIC)-eluting PLGA nanofibers are favorable candidates for treating malignant glioma.

  5. Lasting effect of preceding culture conditions on the susceptibility of C6 cells to peroxide-induced oxidative stress.

    Science.gov (United States)

    Brenner, Sibylle; Gülden, Michael; Maser, Edmund; Seibert, Hasso

    2010-12-01

    The aim of the present study was to investigate the influence of the maintenance culture conditions on the competence of C6 rat glioma cells to cope with peroxide-induced oxidative stress. C6 cells were maintained either in Ham's nutrient mixture F-10 supplemented with 15% horse serum and 2.5% foetal bovine serum (FBS) or in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 5% FBS. The differently cultured cells were exposed under identical conditions to hydrogen peroxide (H₂O₂) and cumene hydroperoxide (CHP) in serum-free DMEM. The cells maintained in high serum Ham's F-10 medium (1) were less sensitive towards the cytotoxic action of both peroxides (EC₅₀-values: H₂O₂: 193 ± 23 μM; CHP: 94 ± 16 μM) than the cells maintained in low serum DMEM (EC₅₀-values: H₂O₂: 51 ± 10 μM; CHP: 27 ± 11 μM), (2) eliminated the peroxides (initial concentration: 100 μM) with higher rates (H₂O₂: 56 ± 5.5 vs. 32 ± 2.7, CHP: 32 ± 6 vs. 3.4 ± 0.6 nmol/min mg protein), (3) contained more glutathione (30 ± 2.5 vs. 14 ± 1.1 nmol/mg protein) and (4) owned a higher glutathione peroxidase activity (28 ± 3.4 vs. 9.5 ± 0.8 mU/mg protein). Glutathione reductase and catalase activities were not affected. These results demonstrate that the preceding culture conditions have a lasting effect on the susceptibility of cultured cells to oxidative stressors like peroxides. As cause for these differences a dissimilar supply of the cells with serum born antioxidants like selenium and α-tocopherol is discussed.

  6. Conditioned Medium from Adipose-Derived Stem Cells (ADSCs) Promotes Epithelial-to-Mesenchymal-Like Transition (EMT-Like) in Glioma Cells In vitro.

    Science.gov (United States)

    Iser, Isabele C; Ceschini, Stefanie M; Onzi, Giovana R; Bertoni, Ana Paula S; Lenz, Guido; Wink, Márcia R

    2016-12-01

    Mesenchymal stem cells (MSCs) have recently been described to home to brain tumors and to integrate into the tumor-associated stroma. Understanding the communication between cancer cells and MSCs has become fundamental to determine whether MSC-tumor interactions should be exploited as a vehicle for therapeutic agents or considered a target for intervention. Therefore, we investigated whether conditioned medium from adipose-derived stem cells (ADSCs-CM) modulate glioma tumor cells by analyzing several cell biology processes in vitro. C6 rat glioma cells were treated with ADSCs-CM, and cell proliferation, cell cycle, cell viability, cell morphology, adhesion, migration, and expression of epithelial-mesenchymal transition (EMT)-related surface markers were analyzed. ADSCs-CM did not alter cell viability, cell cycle, and growth rate of C6 glioma cells but increased their migratory capacity. Moreover, C6 cells treated with ADSC-CM showed reduced adhesion and underwent changes in cell morphology. Up-regulation of EMT-associated markers (vimentin, MMP2, and NRAS) was also observed following treatment with ADSC-CM. Our findings demonstrate that the paracrine factors released by ADSCs are able to modulate glioma cell biology. Therefore, ADSC-tumor cell interactions in a tumor microenvironment must be considered in the design of clinical application of stem cell therapy. Graphical Abstract Factors released by adipose-derived stem cells (ADSCs) may modulate the biology of C6 glioma cells. When C6 cells are exposed to a conditioned medium from adipose-derived stem cells (ADSCs-CM), some of these cells can undergo an EMT-like process and trans-differentiate into cells with a more mesenchymal phenotype, characterized by enhanced expression of EMT-related surface markers, reduced cell adhesion capacity, increased migratory capacity, as well as changes in cell and nuclei morphology.

  7. Current treatment of low grade gliomas

    NARCIS (Netherlands)

    M.J. van den Bent (Martin); T.A.B. Snijders (Tom); J.E.C. Bromberg (Jacolien)

    2012-01-01

    textabstractLow grade gliomas affect predominantly young adults, and have a relatively favorable prognosis compared to grade III and grade IV gliomas. The challenge for an optimal management of these patients is to find the balance between an optimal survival and the preservation of neurological fun

  8. Migration capacity of human umbilical cord mesenchymal stem cells towards glioma in vivo*

    Institute of Scientific and Technical Information of China (English)

    Cungang Fan; Dongliang Wang; Qingjun Zhang; Jingru Zhou

    2013-01-01

    High-grade glioma is the most common malignant primary brain tumor in adults. The poor prognosis of glioma, combined with a resistance to currently available treatments, necessitates the ment of more effective tumor-selective therapies. Stem cel-based therapies are emerging as novel cel-based delivery vehicle for therapeutic agents. In the present study, we successful y isolated human umbilical cord mesenchymal stem cel s by explant culture. The human umbilical cord senchymal stem cel s were adherent to plastic surfaces, expressed specific surface phenotypes of mesenchymal stem cel s as demonstrated by flow cytometry, and possessed multi-differentiation potentials in permissive induction media in vitro. Furthermore, human umbilical cord mesenchymal stem cel s demonstrated excel ent glioma-specific targeting capacity in established rat glioma models after intratumoral injection or contralateral ventricular administration in vivo. The excellent glioma-specific targeting ability and extensive intratumoral distribution of human umbilical cord mesenchymal stem cel s indicate that they may serve as a novel cel ular vehicle for delivering the-rapeutic molecules in glioma therapy.

  9. Inhibition of MMP14 potentiates the therapeutic effect of temozolomide and radiation in gliomas.

    Science.gov (United States)

    Ulasov, Ilya; Thaci, Bart; Sarvaiya, Purvaba; Yi, Ruiyang; Guo, Donna; Auffinger, Brenda; Pytel, Peter; Zhang, Lingjiao; Kim, Chung Kwon; Borovjagin, Anton; Dey, Mahua; Han, Yu; Baryshnikov, Anatoly Y; Lesniak, Maciej S

    2013-08-01

    Metalloproteinases are membrane-bound proteins that play a role in the cellular responses to antiglioma therapy. Previously, it has been shown that treatment of glioma cells with temozolomide (TMZ) and radiation (XRT) induces the expression of metalloproteinase 14 (MMP14). To investigate the role of MMP14 in gliomagenesis, we used several chemical inhibitors which affect MMP14 expression. Of all the inhibitors tested, we found that Marimastat not only inhibits the expression of MMP14 in U87 and U251 glioma cells, but also induces cell cycle arrest. To determine the relationship between MMP14 inhibition and alteration of the cell cycle, we used an RNAi technique. Genetic knockdown of MMP14 in U87 and U251 glioma cells induced G2/M arrest and decreased proliferation. Mechanistically, we show that TMZ and XRT regulated expression of MMP14 in clinical samples and in vitro models through downregulation of microRNA374. In vivo genetic knockdown of MMP14 significantly decreased tumor growth of glioma xenografts and improved survival of glioma-bearing mice. Moreover, the combination of MMP14 silencing with TMZ and XRT significantly improved the survival of glioma-bearing mice compared to a single modality treatment group. Therefore, we show that the inhibition of MMP14 sensitizes tumor cells to TMZ and XRT and could be used as a future strategy for antiglioma therapy.

  10. C6H5NH2 effect on the corrosion inhibition of aluminium in 0.5 M HCl

    Science.gov (United States)

    Omotosho, Olugbenga Adeshola; Okeniyi, Joshua Olusegun; Loto, Cleophas Akintoye; Popoola, Abimbola Patricia Idowu; Fademi, Ekundayo Oluwademilade Jacob; Oladipupo, Segun Isaac; Alabi, Ayomide Samuel; Ajibola, Omokolade Bamidele; Emelieze, Alex Nwabunor

    2017-02-01

    In this paper, C6H6NH2 (aniline) effect on the corrosion of aluminium in 0.5 M (i.e. mol/L) HCl medium was studied using gravimetric method by weight loss measurements and electrochemical technique of corrosion potential and potentiodynamic polarization by cyclic voltamery (CV) instrumentation. By these techniques, corrosion rate obtained from aluminium specimens, in 0.5 HCl test-solution having different concentrations of the hydrogen-containing C6H6NH2 chemical, were requisitely analysed. Results showed that the potentiodynamic corrosion rate excellently correlated (R = 98.94%, Nash-Sutcliffe efficiency = 97.89% and ANOVA p-value = 0.0314) with function of the gravimetric corrosion rate and C6H5NH2 concentration. Both experimental and correlated prediction models identified 0.043 mol/L C6H5NH2 with optimal inhibition efficiency performance η = 84.11% by the experimental or η = 81.15% by the predicted models. Fittings of experimental and correlated data showed the data models followed the Langmuir adsorption isotherm from which favourable adsorption and prevalent physisorption were indicated as the C6H5NH2 corrosion-protection on aluminium metal in the 0.5 M HCl medium.

  11. Angular Differential Cross-Section for Ionization of Helium in C6+ Ion Collision

    Institute of Scientific and Technical Information of China (English)

    A.C.Gagyi-Pálffy; I.F.Barna; L.Gulyás; K.T(o)kési

    2004-01-01

    With the help of the density operator, the angular differential cross-section for ionization of helium is calculated within the framework of the one-centre atomic-orbital close-coupling method. We consider a naked C6+ ion as projectile with an energy of 2.5 MeV/a.u. Our result agrees well with the experimental data and the other theoretical calculations such as the first Born approximation, various Distorted Wave models and the classical trajectory Monte Carlo simulation.

  12. 40 CFR 721.2088 - Carboxylic acids, (C6-C9) branched and linear.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Carboxylic acids, (C6-C9) branched and... Specific Chemical Substances § 721.2088 Carboxylic acids, (C6-C9) branched and linear. (a) Chemical... as carboxylic acids, (C6-C9) branched and linear (PMNs P-93-313, 314, 315, and 316) are subject...

  13. Synthesis and characterization of -phosphorylated thioureas RNHC(S)NHP(O)(OPr)2 (R = 2-MeC6H4, 2,6-Me2C6H3, 2,4,6-Me3C6H2)

    Indian Academy of Sciences (India)

    Damir A Safin; Maria G Babashkina; Michael Bolte; Axel Klein

    2010-05-01

    Reaction of O,O'-diisopropylphosphoric acid isothiocyanate (PrO)2P(O)NCS with 2-methylaniline 2-MeC6H4NH2, 2,6-dimethylaniline 2,6-Me2C6H3NH2 or 2,4,6-trimethylaniline 2,4,6-Me3C6H2NH2 leads to the -phosphorylated thioureas RNHC(S)NHP(O)(OPr)2 (R = 2-MeC6H4-, HLI; 2,6-Me2C6H3-, HLII; 2,4,6-Me3C6H2-, HLIII). The new compounds were investigated by 1H and 31P{1H} NMR spectroscopy, and microanalysis. The molecular structure of the thiourea HLIII was elucidated by single crystal X-ray diffraction analysis. Single crystal X-ray diffraction studies showed HLIII forms both intra- and intermolecular hydrogen bonds, which in turn leads to the formation of polymeric chains. One of the intermolecular hydrogen bonds is of the type N-H$\\cdots$S. Moreover, the formation of intermolecular C-H$\\cdots$ 6 -phenyl interactions was established.

  14. Optimizing a machine learning based glioma grading system using multi-parametric MRI histogram and texture features.

    Science.gov (United States)

    Zhang, Xin; Yan, Lin-Feng; Hu, Yu-Chuan; Li, Gang; Yang, Yang; Han, Yu; Sun, Ying-Zhi; Liu, Zhi-Cheng; Tian, Qiang; Han, Zi-Yang; Liu, Le-De; Hu, Bin-Quan; Qiu, Zi-Yu; Wang, Wen; Cui, Guang-Bin

    2017-07-18

    Current machine learning techniques provide the opportunity to develop noninvasive and automated glioma grading tools, by utilizing quantitative parameters derived from multi-modal magnetic resonance imaging (MRI) data. However, the efficacies of different machine learning methods in glioma grading have not been investigated.A comprehensive comparison of varied machine learning methods in differentiating low-grade gliomas (LGGs) and high-grade gliomas (HGGs) as well as WHO grade II, III and IV gliomas based on multi-parametric MRI images was proposed in the current study. The parametric histogram and image texture attributes of 120 glioma patients were extracted from the perfusion, diffusion and permeability parametric maps of preoperative MRI. Then, 25 commonly used machine learning classifiers combined with 8 independent attribute selection methods were applied and evaluated using leave-one-out cross validation (LOOCV) strategy. Besides, the influences of parameter selection on the classifying performances were investigated. We found that support vector machine (SVM) exhibited superior performance to other classifiers. By combining all tumor attributes with synthetic minority over-sampling technique (SMOTE), the highest classifying accuracy of 0.945 or 0.961 for LGG and HGG or grade II, III and IV gliomas was achieved. Application of Recursive Feature Elimination (RFE) attribute selection strategy further improved the classifying accuracies. Besides, the performances of LibSVM, SMO, IBk classifiers were influenced by some key parameters such as kernel type, c, gama, K, etc. SVM is a promising tool in developing automated preoperative glioma grading system, especially when being combined with RFE strategy. Model parameters should be considered in glioma grading model optimization.

  15. MR Vascular Fingerprinting in Stroke and Brain Tumors Models

    Science.gov (United States)

    Lemasson, B.; Pannetier, N.; Coquery, N.; Boisserand, Ligia S. B.; Collomb, Nora; Schuff, N.; Moseley, M.; Zaharchuk, G.; Barbier, E. L.; Christen, T.

    2016-11-01

    In this study, we evaluated an MRI fingerprinting approach (MRvF) designed to provide high-resolution parametric maps of the microvascular architecture (i.e., blood volume fraction, vessel diameter) and function (blood oxygenation) simultaneously. The method was tested in rats (n = 115), divided in 3 models: brain tumors (9 L, C6, F98), permanent stroke, and a control group of healthy animals. We showed that fingerprinting can robustly distinguish between healthy and pathological brain tissues with different behaviors in tumor and stroke models. In particular, fingerprinting revealed that C6 and F98 glioma models have similar signatures while 9 L present a distinct evolution. We also showed that it is possible to improve the results of MRvF and obtain supplemental information by changing the numerical representation of the vascular network. Finally, good agreement was found between MRvF and conventional MR approaches in healthy tissues and in the C6, F98, and permanent stroke models. For the 9 L glioma model, fingerprinting showed blood oxygenation measurements that contradict results obtained with a quantitative BOLD approach. In conclusion, MR vascular fingerprinting seems to be an efficient technique to study microvascular properties in vivo. Multiple technical improvements are feasible and might improve diagnosis and management of brain diseases.

  16. Glioma cell line proliferation controlled by different chemical functional groups in vitro

    Institute of Scientific and Technical Information of China (English)

    Su-Ju XU; Fu-Zhai CUI; Xiao-Long YU; Xiang-Dong KONG

    2013-01-01

    Glioma cell line C6 cultured on silicon surfaces modified by different chemical functional groups, including mercapto (-SH), carboxyl (-COOH), amino (-NH2), hydroxyl (-OH) and methyl (-CH3) groups, was studied here to investigate the influence of surface chemistry on the cell proliferation, adhesion and apoptosis. AFM confirmed the similar characteristic of different functional groups occupation. The adhering C6 exhibited morphological changes in response to different chemical functional groups. The C6 adhered to -COOH, -NH2, -OH and -CH3 surfaces and flattened morphology, while those on -SH surface exhibited the smallest contact area with mostly rounded morphology, which led to the death of cancer cells. The results of MTT assay showed that the -COOH and -NH2 groups promoted ceil proliferation, while the -SH significantly inhibited the proliferation. Compared with other chemical functional groups, the -SH group exhibited its unique effect on the fate of cancer cells, which might provide means for the design of biomaterials to prevent and treat glioma.

  17. Cytochrome c(6B) of Synechococcus sp. WH 8102--crystal structure and basic properties of novel c(6)-like family representative.

    Science.gov (United States)

    Zatwarnicki, Pawel; Barciszewski, Jakub; Krzywda, Szymon; Jaskolski, Mariusz; Kolesinski, Piotr; Szczepaniak, Andrzej

    2014-01-24

    Cytochromes c are soluble electron carriers of relatively low molecular weight, containing single heme moiety. In cyanobacteria cytochrome c6 participates in electron transfer from cytochrome b6f complex to photosystem I. Recent phylogenetic analysis revealed the existence of a few families of proteins homologous to the previously mentioned. Cytochrome c6A from Arabidopsis thaliana was identified as a protein responsible for disulfide bond formation in response to intracellular redox state changes and c550 is well known element of photosystem II. However, function of cytochromes marked as c6B, c6C and cM as well as the physiological process in which they take a part still remain unidentified. Here we present the first structural and biophysical analysis of cytochrome from the c6B family from mesophilic cyanobacteria Synechococcus sp. WH 8102. Purified protein was crystallized and its structure was refined at 1.4 Å resolution. Overall architecture of this polypeptide resembles typical I-class cytochromes c. The main features, that distinguish described protein from cytochrome c6, are slightly red-shifted α band of UV-Vis spectrum as well as relatively low midpoint potential (113.2±2.2 mV). Although, physiological function of cytochrome c6B has yet to be determined its properties probably exclude the participation of this protein in electron trafficking between b6f complex and photosystem I.

  18. Meat and haem iron intake in relation to glioma in the European Prospective Investigation into Cancer and Nutrition study.

    Science.gov (United States)

    Ward, Heather A; Gayle, Alicia; Jakszyn, Paula; Merritt, Melissa; Melin, Beatrice; Freisling, Heinz; Weiderpass, Elisabete; Tjonneland, Anne; Olsen, Anja; Dahm, Christina C; Overvad, Kim; Katzke, Verena; Kühn, Tilman; Boeing, Heiner; Trichopoulou, Antonia; Lagiou, Pagona; Kyrozis, Andreas; Palli, Domenico; Krogh, Vittorio; Tumino, Rosario; Ricceri, Fulvio; Mattiello, Amalia; Bueno-de-Mesquita, Bas; Peeters, Petra H; Quirós, José Ramón; Agudo, Antonio; Rodriguez-Barranco, Miguel; Larrañaga, Nerea; Huerta, José M; Barricarte, Aurelio; Sonestedt, Emily; Drake, Isabel; Sandström, Maria; Travis, Ruth C; Ferrari, Pietro; Riboli, Elio; Cross, Amanda J

    2016-11-11

    Diets high in red or processed meat have been associated positively with some cancers, and several possible underlying mechanisms have been proposed, including iron-related pathways. However, the role of meat intake in adult glioma risk has yielded conflicting findings because of small sample sizes and heterogeneous tumour classifications. The aim of this study was to examine red meat, processed meat and iron intake in relation to glioma risk in the European Prospective Investigation into Cancer and Nutrition study. In this prospective cohort study, 408 751 individuals from nine European countries completed demographic and dietary questionnaires at recruitment. Multivariable Cox proportional hazards models were used to examine intake of red meat, processed meat, total dietary iron and haem iron in relation to incident glioma. During an average follow-up of 14.1 years, 688 incident glioma cases were diagnosed. There was no evidence that any of the meat variables (red, processed meat or subtypes of meat) or iron (total or haem) were associated with glioma; results were unchanged when the first 2 years of follow-up were excluded. This study suggests that there is no association between meat or iron intake and adult glioma. This is the largest prospective analysis of meat and iron in relation to glioma and as such provides a substantial contribution to a limited and inconsistent literature.

  19. RNA Sequencing of Tumor-Associated Microglia Reveals Ccl5 as a Stromal Chemokine Critical for Neurofibromatosis-1 Glioma Growth

    Directory of Open Access Journals (Sweden)

    Anne C. Solga

    2015-10-01

    Full Text Available Solid cancers develop within a supportive microenvironment that promotes tumor formation and growth through the elaboration of mitogens and chemokines. Within these tumors, monocytes (macrophages and microglia represent rich sources of these stromal factors. Leveraging a genetically engineered mouse model of neurofibromatosis type 1 (NF1 low-grade brain tumor (optic glioma, we have previously demonstrated that microglia are essential for glioma formation and maintenance. To identify potential tumor-associated microglial factors that support glioma growth (gliomagens, we initiated a comprehensive large-scale discovery effort using optimized RNA-sequencing methods focused specifically on glioma-associated microglia. Candidate microglial gliomagens were prioritized to identify potential secreted or membrane-bound proteins, which were next validated by quantitative real-time polymerase chain reaction as well as by RNA fluorescence in situ hybridization following minocycline-mediated microglial inactivation in vivo. Using these selection criteria, chemokine (C-C motif ligand 5 (Ccl5 was identified as a chemokine highly expressed in genetically engineered Nf1 mouse optic gliomas relative to nonneoplastic optic nerves. As a candidate gliomagen, recombinant Ccl5 increased Nf1-deficient optic nerve astrocyte growth in vitro. Importantly, consistent with its critical role in maintaining tumor growth, treatment with Ccl5 neutralizing antibodies reduced Nf1 mouse optic glioma growth and improved retinal dysfunction in vivo. Collectively, these findings establish Ccl5 as an important microglial growth factor for low-grade glioma maintenance relevant to the development of future stroma-targeted brain tumor therapies.

  20. Application of MR stem cell markers in research of temozolomide intervention gliomas angiogenesis and therapy%MR干细胞标记在替莫唑胺干预脑胶质瘤血管生成及治疗研究中的应用

    Institute of Scientific and Technical Information of China (English)

    陈伟志; 杨重恒

    2015-01-01

    目的:探究MR干细胞标记在替莫唑胺干预脑胶质瘤血管生成及治疗中的作用。方法通过C6胶质瘤细胞株静脉注射建立大鼠脑胶质瘤的动物模型,采用MR干细胞标记技术以及免疫组化观测肿瘤生长及新生血管的生成,对比影像学与免疫组化检测结果,进行2者间的相关性分析。结果本研究成功运用MR扫描示踪SPIO-PLL共同标记的骨髓干细胞,动态检测了脑胶质瘤模型大鼠脑内肿瘤血管生成情况。影像学与免疫组化相关性分析结果显示,2者呈现良好的负相关性( P<0.05)。结论 SPIO对于骨髓干细胞的磁性标记标记和MR示踪技术是活体动态观察脑胶质瘤血管生成的有效手段。%Objective To explore the role of MR stem cell markers in temozolomide intervention gliomas angiogenesis and therapy .Methods C6 glioma cells were intravenously injected in glioma model rat.MR stem cell markers and immunohistochemistry were used to observe the tumor growth and angiogenesis.Correlation of contrast imaging and immunohistochemistry results were studied.Results In this study, MR scanning was successfully used to trace the SPIO-PLL marked bone marrow stem cells, dynamic testing of angiogenesis in rat brain glioma tumor.Correlation analysis of imaging and immunohistochemical showed that they had a good negative correlation (P<0.05).Conclusion SPIO magnetic markers for bone marrow stem cells and MR tracing technique is an effective means of dynamic observation in vivo glioma angiogenesis.

  1. Magnetic paclitaxel nanoparticles inhibit glioma growth and improve the survival of rats bearing glioma xenografts.

    Science.gov (United States)

    Zhao, Ming; Liang, Chao; Li, Anmin; Chang, Jin; Wang, Hanjie; Yan, Runmin; Zhang, Jiajing; Tai, Junli

    2010-06-01

    Paclitaxel has fared poorly in clinical trials against brain glioma. We hypothesized that superparamagnetic nanocarriers may enhance its bioactivities by delivering it into the brain. The magnetic paclitaxel nanoparticles (MPNPs) were fabricated and their cytotoxicity against glioma was tested both in vitro and in glioma-bearing rats. MPNPs exhibited superparamagnetism and produced an extended release of paclitaxel over 15 days in vitro. They were easily internalized into glioma cells and exerted remarkable toxicity, as free paclitaxel did. Furthermore, after intravenous injection of MPNPs to glioma-bearing rats and magnetic targeting with a 0.5 T magnet, drug content increased for 6- to 14-fold in implanted glioma and 4.6- to 12.1-fold in the normal brain compared to free paclitaxel. The survival of glioma-bearing rats was significantly prolonged after magnetic targeting therapy with MPNPs. MPNPs efficiently delivered paclitaxel into brain glioma by magnetic targeting and enhance its antitumor activity. They are promising for local chemotherapy for malignant glioma.

  2. Focal radiation therapy combined with 4-1BB activation and CTLA-4 blockade yields long-term survival and a protective antigen-specific memory response in a murine glioma model.

    Directory of Open Access Journals (Sweden)

    Zineb Belcaid

    Full Text Available BACKGROUND: Glioblastoma (GBM is the most common malignant brain tumor in adults and is associated with a poor prognosis. Cytotoxic T lymphocyte antigen -4 (CTLA-4 blocking antibodies have demonstrated an ability to generate robust antitumor immune responses against a variety of solid tumors. 4-1BB (CD137 is expressed by activated T lymphocytes and served as a co-stimulatory signal, which promotes cytotoxic function. Here, we evaluate a combination immunotherapy regimen involving 4-1BB activation, CTLA-4 blockade, and focal radiation therapy in an immune-competent intracranial GBM model. METHODS: GL261-luciferace cells were stereotactically implanted in the striatum of C57BL/6 mice. Mice were treated with a triple therapy regimen consisted of 4-1BB agonist antibodies, CTLA-4 blocking antibodies, and focal radiation therapy using a small animal radiation research platform and mice were followed for survival. Numbers of brain-infiltrating lymphocytes were analyzed by FACS analysis. CD4 or CD8 depleting antibodies were administered to determine the relative contribution of T helper and cytotoxic T cells in this regimen. To evaluate the ability of this immunotherapy to generate an antigen-specific memory response, long-term survivors were re-challenged with GL261 glioma en B16 melanoma flank tumors. RESULTS: Mice treated with triple therapy had increased survival compared to mice treated with focal radiation therapy and immunotherapy with 4-1BB activation and CTLA-4 blockade. Animals treated with triple therapy exhibited at least 50% long-term tumor free survival. Treatment with triple therapy resulted in a higher density of CD4+ and CD8+ tumor infiltrating lymphocytes. Mechanistically, depletion of CD4+ T cells abrogated the antitumor efficacy of triple therapy, while depletion of CD8+ T cells had no effect on the treatment response. CONCLUSION: Combination therapy with 4-1BB activation and CTLA-4 blockade in the setting of focal radiation therapy

  3. Crossed beam reaction of cyano radicals with hydrocarbon molecules. I. Chemical dynamics of cyanobenzene (C6H5CN; X 1A1) and perdeutero cyanobenzene (C6D5CN; X 1A1) formation from reaction of CN(X 2Σ+) with benzene C6H6(X 1A1g), and d6-benzene C6D6(X 1A1g)

    Science.gov (United States)

    Balucani, N.; Asvany, O.; Chang, A. H. H.; Lin, S. H.; Lee, Y. T.; Kaiser, R. I.; Bettinger, H. F.; Schleyer, P. v. R.; Schaefer, H. F.

    1999-10-01

    The chemical reaction dynamics to form cyanobenzene C6H5CN(X 1A1), and perdeutero cyanobenzene C6D5CN(X 1A1) via the neutral-neutral reaction of the cyano radical CN(X 2Σ+), with benzene C6H6(X 1A1g) and perdeutero benzene C6D6(X 1A1g), were investigated in crossed molecular beam experiments at collision energies between 19.5 and 34.4 kJ mol-1. The laboratory angular distributions and time-of-flight spectra of the products were recorded at mass to charge ratios m/e=103-98 and 108-98, respectively. Forward-convolution fitting of our experimental data together with electronic structure calculations (B3LYP/6-311+G**) indicate that the reaction is without entrance barrier and governed by an initial attack of the CN radical on the carbon side to the aromatic π electron density of the benzene molecule to form a Cs symmetric C6H6CN(C6D6CN) complex. At all collision energies, the center-of-mass angular distributions are forward-backward symmetric and peak at π/2. This shape documents that the decomposing intermediate has a lifetime longer than its rotational period. The H/D atom is emitted almost perpendicular to the C6H5CN plane, giving preferentially sideways scattering. This experimental finding can be rationalized in light of the electronic structure calculations depicting a H-C-C angle of 101.2° in the exit transition state. The latter is found to be tight and located about 32.8 kJ mol-1 above the products. Our experimentally determined reaction exothermicity of 80-95 kJ mol-1 is in good agreement with the theoretically calculated one of 94.6 kJ mol-1. Neither the C6H6CN adduct nor the stable iso cyanobenzene isomer C6H5NC were found to contribute to the scattering signal. The experimental identification of cyanobenzene gives a strong background for the title reaction to be included with more confidence in reaction networks modeling the chemistry in dark, molecular clouds, outflow of dying carbon stars, hot molecular cores, as well as the atmosphere of hydrocarbon

  4. The ketogenic diet for the treatment of malignant glioma.

    Science.gov (United States)

    Woolf, Eric C; Scheck, Adrienne C

    2015-01-01

    Advances in our understanding of glioma biology has led to an increase in targeted therapies in preclinical and clinical trials; however, cellular heterogeneity often precludes the targeted molecules from being found on all glioma cells, thus reducing the efficacy of these treatments. In contrast, one trait shared by virtually all tumor cells is altered (dysregulated) metabolism. Tumor cells have an increased reliance on glucose, suggesting that treatments affecting cellular metabolism may be an effective method to improve current therapies. Indeed, metabolism has been a focus of cancer research in the last few years, as many pathways long associated with tumor growth have been found to intersect metabolic pathways in the cell. The ketogenic diet (high fat, low carbohydrate and protein), caloric restriction, and fasting all cause a metabolic change, specifically, a reduction in blood glucose and an increase in blood ketones. We, and others, have demonstrated that these metabolic changes improve survival in animal models of malignant gliomas and can potentiate the anti-tumor effect of chemotherapies and radiation treatment. In this review we discuss the use of metabolic alteration for the treatment of malignant brain tumors.

  5. Dipeptidyl peptidase IV in two human glioma cell lines

    Directory of Open Access Journals (Sweden)

    A Sedo

    2009-12-01

    Full Text Available There is growing evidence that dipeptidyl peptidase IV [DPP-IV, EC 3.4.14.5] takes part in the metabolism of biologically active peptides participating in the regulation of growth and transformation of glial cells. However, the knowledge on the DPP-IV expression in human glial and glioma cells is still very limited. In this study, using histochemical and biochemical techniques, the DPP-IV activity was demonstrated in two commercially available human glioma cell lines of different transformation degree, as represented by U373 astrocytoma (Grade III and U87 glioblastoma multiforme (Grade IV lines. Higher total activity of the enzyme, as well as its preferential localisation in the plasma membrane, was observed in U87 cells. Compared to U373 population, U87 cells were morphologically more pleiomorphic, they were cycling at lower rate and expressing less Glial Fibrillary Acidic Protein. The data revealed positive correlation between the degree of transformation of cells and activity of DPP-IV. Great difference in expression of this enzyme, together with the phenotypic differences of cells, makes these lines a suitable standard model for further 57 studies of function of this enzyme in human glioma cells.

  6. Atypical crossmodal emotional integration in patients with gliomas.

    Science.gov (United States)

    Luherne-du Boullay, Viviane; Plaza, Monique; Perrault, Annabelle; Capelle, Laurent; Chaby, Laurence

    2014-11-01

    The relevance of emotional perception in interpersonal relationships and social cognition has been well documented. Although brain diseases might impair emotional processing, studies concerning emotional recognition in patients with brain tumours are relatively rare. The aim of this study was to explore emotional recognition in patients with gliomas in three conditions (visual, auditory and crossmodal) and to analyse how tumour-related variables (notably, tumour localisation) and patient-related variables influence emotion recognition. Twenty six patients with gliomas and 26 matched healthy controls were instructed to identify 5 basic emotions and a neutral expression, which were displayed through visual, auditory and crossmodal stimuli. Relative to the controls, recognition was weakly impaired in the patient group under both visual and auditory conditions, but the performances were comparable in the crossmodal condition. Additional analyses using the 'race model' suggest differences in multisensory emotional integration abilities across the groups, which were potentially correlated with the executive disorders observed in the patients. These observations support the view of compensatory mechanisms in the case of gliomas that might preserve the quality of life and help maintain the normal social and professional lives often observed in these patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Nqrs Data for C6H16I2N2O8 [C6H14N2O2·2(HIO3)] (Subst. No. 0931)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C6H16I2N2O8 [C6H14N2O2·2(HIO3)] (Subst. No. 0931)

  8. Nqrs Data for C6H16I2N4O8 [C6H14N4O2·2(HIO3)] (Subst. No. 0932)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C6H16I2N4O8 [C6H14N4O2·2(HIO3)] (Subst. No. 0932)

  9. Nqrs Data for C6H17I3N2O11 [C6H14N2O2·3(HIO3)] (Subst. No. 0933)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C6H17I3N2O11 [C6H14N2O2·3(HIO3)] (Subst. No. 0933)

  10. Nqrs Data for C6H20I6N2O20 [C6H14N2O2·6(HIO3)] (Subst. No. 0939)

    Science.gov (United States)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C6H20I6N2O20 [C6H14N2O2·6(HIO3)] (Subst. No. 0939)

  11. High bone sialoprotein (BSP expression correlates with increased tumor grade and predicts a poorer prognosis of high-grade glioma patients.

    Directory of Open Access Journals (Sweden)

    Tao Xu

    Full Text Available OBJECTIVES: To investigate the expression and prognostic value of bone sialoprotein (BSP in glioma patients. METHODS: We determined the expression of BSP using real-time RT-PCR and immunohistochemistry in tissue microarrays containing 15 normal brain and 270 glioma samples. Cumulative survival was calculated by the Kaplan-Meier method and analyzed by the log-rank test. Univariate and multivariate analyses were performed by the stepwise forward Cox regression model. RESULTS: Both BSP mRNA and protein levels were significantly elevated in high-grade glioma tissues compared with those of normal brain and low-grade glioma tissues, and BSP expression positively correlated with tumor grade (P<0.001. Univariate and multivariate analysis showed high BSP expression was an independent prognostic factor for a shorter progression-free survival (PFS and overall survival (OS in both grade III and grade IV glioma patients [hazard ratio (HR = 2.549 and 3.154 for grade III glioma, and HR = 1.637 and 1.574 for grade IV glioma, respectively]. Patients with low BSP expression had a significantly longer median OS and PFS than those with high BSP expression. Small extent of resection and lineage of astrocyte served as independent risk factors of both shorter PFS and OS in grade III glioma patients; GBM patients without O(6-methylguanine (O(6-meG DNA methyltransferase (MGMT methylation and Karnofsky performance score (KPS less than 70 points were related to poor prognosis. Lack of radiotherapy related to shorter OS but not affect PFS in both grade III and grade IV glioma patients. CONCLUSION: High BSP expression occurs in a significant subset of high-grade glioma patients and predicts a poorer outcome. The study identifies a potentially useful molecular marker for the categorization and targeted therapy of gliomas.

  12. Ne matrix spectra of the sym-C6Br3F3+ radical cation

    Science.gov (United States)

    Bondybey, V.E.; Sears, T.J.; Miller, T.A.; Vaughn, C.; English, J.H.; Shiley, R.S.

    1981-01-01

    The electronic absorption and laser excited, wavelength resolved fluorescence spectra of the title cation have been observed in solid Ne matrix and vibrationally analysed. The vibrational structure of the excited B2A2??? state shows close similarity to the parent compound. The X2E??? ground state structure is strongly perturbed and irregular owing to a large Jahn-Teller distortion. The data are analysed in terms of a recently developed, sophisticated multimode Jahn-Teller theoretical model. We have generated the sym-C6Br3F3+ cations in solid Ne matrix and obtained their wavelength resolved emission and absorption spectra. T ground electronic X2E??? state exhibits an irregular and strongly perturbed vibrational structure, which can be successfully modeled using sophisticated multimode Jahn-Teller theory. ?? 1981.

  13. Identification of proteins involved in neural progenitor cell targeting of gliomas

    Directory of Open Access Journals (Sweden)

    Honeth Gabriella

    2009-06-01

    Full Text Available Abstract Background Glioblastoma are highly aggressive tumors with an average survival time of 12 months with currently available treatment. We have previously shown that specific embryonic neural progenitor cells (NPC have the potential to target glioma growth in the CNS of rats. The neural progenitor cell treatment can cure approximately 40% of the animals with malignant gliomas with no trace of a tumor burden 6 months after finishing the experiment. Furthermore, the NPCs have been shown to respond to signals from the tumor environment resulting in specific migration towards the tumor. Based on these results we wanted to investigate what factors could influence the growth and progression of gliomas in our rodent model. Methods Using microarrays we screened for candidate genes involved in the functional mechanism of tumor inhibition by comparing glioma cell lines to neural progenitor cells with or without anti-tumor activity. The expression of candidate genes was confirmed at RNA level by quantitative RT-PCR and at the protein level by Western blots and immunocytochemistry. Moreover, we have developed in vitro assays to mimic the antitumor effect seen in vivo. Results We identified several targets involved in glioma growth and migration, specifically CXCL1, CD81, TPT1, Gas6 and AXL proteins. We further showed that follistatin secretion from the NPC has the potential to decrease tumor proliferation. In vitro co-cultures of NPC and tumor cells resulted in the inhibition of tumor growth. The addition of antibodies against proteins selected by gene and protein expression analysis either increased or decreased the proliferation rate of the glioma cell lines in vitro. Conclusion These results suggest that these identified factors might be useful starting points for performing future experiments directed towards a potential therapy against malignant gliomas.

  14. Prognostic value of blood flow measurements using arterial spin labeling in gliomas.

    Directory of Open Access Journals (Sweden)

    Julia Furtner

    Full Text Available The period of event-free survival (EFS within the same histopathological glioma grades may have high variability, mainly without a known cause. The purpose of this study was to reveal the prognostic value of quantified tumor blood flow (TBF values obtained by arterial spin labeling (ASL for EFS in patients with histopathologically proven astrocytomas independent of WHO (World Health Organization grade. Twenty-four patients with untreated gliomas underwent tumor perfusion quantification by means of pulsed ASL in 3T. The clinical history of the patients was retrospectively extracted from the local database. Six patients had to be excluded due to insufficent follow-up data for further evaluation or histopathologically verified oligodendroglioma tumor components. Receiver operating characteristic (ROC curves were used to define an optimal cut-off value of maximum TBF (mTBF values for subgrouping in low-perfused and high-perfused gliomas. Kaplan-Meier curves and Cox proportional hazard regression model were used to determine the prognostic value of mTBF for EFS. An optimal mTBF cut-off value of 182 ml/100 g/min (sensitivity  = 83%, specificity  = 100% was determined. Patients with low-perfused gliomas had significantly longer EFS compared to patients with high-perfused gliomas (p = 0.0012 independent of the WHO glioma grade. Quantified mTBF values obtained by ASL offer a new and totally non-invasive marker to prognosticate the EFS, independently on histopathological tumor grading, in patients with gliomas.

  15. Convection-enhancement delivery of platinum-based drugs and Lipoplatin™ to optimize the concomitant effect with radiotherapy in F98 glioma rat model

    Science.gov (United States)

    Shi, Minghan; Fortin, David; Sanche, Léon; Paquette, Benoit

    2015-01-01

    The prognosis for patients with glioblastoma remains poor with current treatments. Although platinum based drugs are sometimes offered at relapse, their efficacy in this setting is still disputed. In this study, we use convection-enhanced delivery (CED) to deliver the platinum-based drugs (cisplatin, carboplatin, and Lipoplatin™-liposomal formulation of cisplatin) directly into the tumor of F98 glioma-bearing rats that were subsequently treated with γ radiation (15 Gy). CED increased by factors varying between 17 and 111, the concentration of these platinum-based drugs in the brain tumor compared to intra-venous (i.v.) administration, and by 9- to 34-fold, when compared to intra-arterial (i.a.) administration. Furthermore, CED resulted in a better systemic tolerance to platinum drugs compared to their i.a. injection. Among the drugs tested, carboplatin showed the highest maximum tolerated dose (MTD). Treatment with carboplatin resulted in the best median survival time (MeST) (38.5 days), which was further increased by the addition of radiotherapy (54.0 days). Although the DNA-bound platinum adduct were higher at 4 h after CED than 24 h for carboplatin group, combination with radiotherapy led to similar improvement of median survival time. However, less toxicity was observed in animals irradiated 24 h after CED-based chemotherapy. In conclusion, CED increased the accumulation of platinum drugs in tumor, reduced the toxicity, and resulted in a higher median survival time. The best treatment was obtained in animals treated with carboplatin and irradiated 24 h later. PMID:25784204

  16. Convection-enhancement delivery of platinum-based drugs and Lipoplatin(TM) to optimize the concomitant effect with radiotherapy in F98 glioma rat model.

    Science.gov (United States)

    Shi, Minghan; Fortin, David; Sanche, Léon; Paquette, Benoit

    2015-06-01

    The prognosis for patients with glioblastoma remains poor with current treatments. Although platinum-based drugs are sometimes offered at relapse, their efficacy in this setting is still disputed. In this study, we use convection-enhanced delivery (CED) to deliver the platinum-based drugs (cisplatin, carboplatin, and Lipoplatin(TM) - liposomal formulation of cisplatin) directly into the tumor of F98 glioma-bearing rats that were subsequently treated with γ radiation (15 Gy). CED increased by factors varying between 17 and 111, the concentration of these platinum-based drugs in the brain tumor compared to intra-venous (i.v.) administration, and by 9- to 34-fold, when compared to intra-arterial (i.a.) administration. Furthermore, CED resulted in a better systemic tolerance to platinum drugs compared to their i.a. injection. Among the drugs tested, carboplatin showed the highest maximum tolerated dose (MTD). Treatment with carboplatin resulted in the best median survival time (MeST) (38.5 days), which was further increased by the addition of radiotherapy (54.0 days). Although the DNA-bound platinum adduct were higher at 4 h after CED than 24 h for carboplatin group, combination with radiotherapy led to similar improvement of median survival time. However, less toxicity was observed in animals irradiated 24 h after CED-based chemotherapy. In conclusion, CED increased the accumulation of platinum drugs in tumor, reduced the toxicity, and resulted in a higher median survival time. The best treatment was obtained in animals treated with carboplatin and irradiated 24 h later.

  17. Adult high-grade malignant gliomas

    Directory of Open Access Journals (Sweden)

    Fable Zustovich

    2011-12-01

    Full Text Available Central nervous system (CNS malignant gliomas are relatively rare diseases. Prognosis is poor but has improved over recent years due to the improvement in the multi-disciplinary treatment: surgery, radiotherapy and chemotherapy...

  18. Targeting immune checkpoints in malignant glioma

    Science.gov (United States)

    Li, Tete; Liu, Yong-Jun; Chen, Wei; Chen, Jingtao

    2017-01-01

    Malignant glioma is the most common and a highly aggressive cancer in the central nervous system (CNS). Cancer immunotherapy, strategies to boost the bodys anti-cancer immune responses instead of directly targeting tumor cells, recently achieved great success in treating several human solid tumors. Although once considered immune privileged and devoid of normal immunological functions, CNS is now considered a promising target for cancer immunotherapy, featuring the recent progresses in neurobiology and neuroimmunology and a highly immunosuppressive state in malignant glioma. In this review, we focus on immune checkpoint inhibitors, specifically, antagonizing monoclonal antibodies for programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), and indoleamine 2,3-dioxygenase (IDO). We discuss advances in the working mechanisms of these immune checkpoint molecules, their status in malignant glioma, and current preclinical and clinical trials targeting these molecules in malignant glioma. PMID:27756892

  19. The Art of Intraoperative Glioma Identification

    Directory of Open Access Journals (Sweden)

    Zoe Z Zhang

    2015-07-01

    Full Text Available A major dilemma in brain tumor surgery is the identification of tumor boundaries to maximize tumor excision and minimize postoperative neurological damage. Gliomas, especially low-grade tumors, and normal brain have a similar color and texture which poses a challenge to the neurosurgeon. Advances in glioma resection techniques combine the experience of the neurosurgeon and various advanced technologies. Intraoperative methods to delineate gliomas from normal tissue consist of 1 image-based navigation, 2 intraoperative sampling, 3 electrophysiological monitoring, and 4 enhanced visual tumor demarcation. The advantages and disadvantages of each technique are discussed. A combination of these methods is becoming widely accepted in routine glioma surgery. Gross total resection in conjunction with radiation, chemotherapy, or immune/gene therapy may increase the rates of cure in this devastating disease.

  20. The combined effect of encapsulating curcumin and C6 ceramide in liposomal nanoparticles against osteosarcoma.

    Science.gov (United States)

    Dhule, Santosh S; Penfornis, Patrice; He, Jibao; Harris, Michael R; Terry, Treniece; John, Vijay; Pochampally, Radhika

    2014-02-01

    This study examines the antitumor potential of curcumin and C6 ceramide (C6) against osteosarcoma (OS) cell lines when both are encapsulated in the bilayer of liposomal nanoparticles. Three liposomal formulations were prepared: curcumin liposomes, C6 liposomes and C6-curcumin liposomes. Curcumin in combination with C6 showed 1.5 times enhanced cytotoxic effect in the case of MG-63 and KHOS OS cell lines, in comparison with curcumin liposomes alone. Importantly, C6-curcumin liposomes were found to be less toxic on untransformed primary human cells (human mesenchymal stem cells) in comparison to OS cell lines. In addition, cell cycle assays on a KHOS cell line after treatment revealed that curcumin only liposomes induced G2/M arrest by upregulation of cyclin B1, while C6 only liposomes induced G1 arrest by downregulation of cyclin D1. C6-curcumin liposomes induced G2/M arrest and showed a combined effect in the expression levels of cyclin D1 and cyclin B1. The efficiency of the preparations was tested in vivo using a human osteosarcoma xenograft assay. Using pegylated liposomes to increase the plasma half-life and tagging with folate (FA) for targeted delivery in vivo, a significant reduction in tumor size was observed with C6-curcumin-FA liposomes. The encapsulation of two water insoluble drugs, curcumin and C6, in the lipid bilayer of liposomes enhances the cytotoxic effect and validates the potential of combined drug therapy.

  1. Platelet-derived growth factor receptor alpha in glioma: a bad seed

    Institute of Scientific and Technical Information of China (English)

    Kun-Wei Liu; Bo Hu; Shi-Yuan Cheng

    2011-01-01

    Recent collaborative,large-scale genomic profiling of the most common and aggressive brain tumor glioblastoma multiforme(GBM) has significantly advanced our understanding of this disease.The gene encoding platelet-derived growth factor receptor alpha (PDGFRα) was identified as the third of the top 11 amplified genes in clinical GBM specimens.The important roles of PDGFRα signaling during normal brain development also implicate the possible pathologic consequences of PDGFRα over-activation in glioma.Although the initial clinical trials using PDGFR kinase inhibitors have been predominantly disappointing,diagnostic and treatment modalities involving genomic profiling and personalized medicine are expected to improve the therapy targeting PDGFRα signaling.In this review,we discuss the roles of PDGFRα signaling during development of the normal central nervous system (CNS) and in pathologic conditions such as malignant glioma.We further compare various animal models of PDGF-induced gliomagenesis and their potential as a novel platform of pre-clinical drug testing.We then summarize our recent publication and how these findings will likely impact treatments for gliomas driven by PDGFRα overexpression.A better understanding of PDGFRα signaling in glioma and their microenvironment,through the use of human or mouse models,is necessary to design a more effective therapeutic strategy against gliomas harboring the aberrant PDGFRα signaling.

  2. Post Traumatic Glioma – An association questioned

    Directory of Open Access Journals (Sweden)

    Chaurasia I.D.

    2015-03-01

    Full Text Available Post traumatic glioma has been a matter of debate. Few reports favor its occurrence in previous head injury scar, subsequently developing into glioma. Here we report a case of young patient presented with headache, seizures and gradual loss of vision. On investigation found to have brain tumor. Patient had head injury occurred 3 yrs back. It fulfills all the criteria required to establish traumatic origin, further supporting the association.

  3. Targeted Radiolabeled Compounds in Glioma Therapy.

    Science.gov (United States)

    Cordier, Dominik; Krolicki, Leszek; Morgenstern, Alfred; Merlo, Adrian

    2016-05-01

    Malignant gliomas of World Health Organization (WHO) grades II-IV represent the largest entity within the group of intrinsic brain tumors and are graded according to their pathophysiological features with survival times between more than 10 years (WHO II) and only several months (WHO IV). Gliomas arise from astrocytic or oligodendrocytic precursor cells and exhibit an infiltrative growth pattern lacking a clearly identifiable tumor border. The development of effective treatment strategies of the invasive tumor cell front represents the main challenge in glioma therapy. The therapeutic standard consists of surgical resection and, depending on the extent of resection and WHO grade, adjuvant external beam radiotherapy or systemic chemotherapy. Within the last decades, there has been no major improvement of the prognosis of patients with glioma. The consistent overexpression of neurokinin type 1 receptors in gliomas WHO grades II-IV has been used to develop a therapeutic substance P-based targeting system. A substance P-analogue conjugated to the DOTA or DOTAGA chelator has been labeled with different alpha-particle or beta-particle emitting radionuclides for targeted glioma therapy. The radiopharmaceutical has been locally injected into the tumors or the resection cavity. In several clinical studies, the methodology has been examined in adjuvant and neoadjuvant clinical settings. Although no large controlled series have so far been generated, the results of radiolabeled substance P-based targeted glioma therapy compare favorably with standard therapy. Recently, labeling with the alpha particle emitting Bi-213 has been found to be promising due to the high linear energy transfer and the very short tissue range of 0.08 mm. Further development needs to focus on the improvement of the stability of the compound and the application by dedicated catheter systems to improve the intratumoral distribution of the radiopharmaceutical within the prognostically critical

  4. Vaccinia virus protein C6 is a virulence factor that binds TBK-1 adaptor proteins and inhibits activation of IRF3 and IRF7.

    Directory of Open Access Journals (Sweden)

    Leonie Unterholzner

    2011-09-01

    Full Text Available Recognition of viruses by pattern recognition receptors (PRRs causes interferon-β (IFN-β induction, a key event in the anti-viral innate immune response, and also a target of viral immune evasion. Here the vaccinia virus (VACV protein C6 is identified as an inhibitor of PRR-induced IFN-β expression by a functional screen of select VACV open reading frames expressed individually in mammalian cells. C6 is a member of a family of Bcl-2-like poxvirus proteins, many of which have been shown to inhibit innate immune signalling pathways. PRRs activate both NF-κB and IFN regulatory factors (IRFs to activate the IFN-β promoter induction. Data presented here show that C6 inhibits IRF3 activation and translocation into the nucleus, but does not inhibit NF-κB activation. C6 inhibits IRF3 and IRF7 activation downstream of the kinases TANK binding kinase 1 (TBK1 and IκB kinase-ε (IKKε, which phosphorylate and activate these IRFs. However, C6 does not inhibit TBK1- and IKKε-independent IRF7 activation or the induction of promoters by constitutively active forms of IRF3 or IRF7, indicating that C6 acts at the level of the TBK1/IKKε complex. Consistent with this notion, C6 immunoprecipitated with the TBK1 complex scaffold proteins TANK, SINTBAD and NAP1. C6 is expressed early during infection and is present in both nucleus and cytoplasm. Mutant viruses in which the C6L gene is deleted, or mutated so that the C6 protein is not expressed, replicated normally in cell culture but were attenuated in two in vivo models of infection compared to wild type and revertant controls. Thus C6 contributes to VACV virulence and might do so via the inhibition of PRR-induced activation of IRF3 and IRF7.

  5. GliomaPredict: a clinically useful tool for assigning glioma patients to specific molecular subtypes

    Directory of Open Access Journals (Sweden)

    Fine Howard A

    2010-07-01

    Full Text Available Abstract Background Advances in generating genome-wide gene expression data have accelerated the development of molecular-based tumor classification systems. Tools that allow the translation of such molecular classification schemas from research into clinical applications are still missing in the emerging era of personalized medicine. Results We developed GliomaPredict as a computational tool that allows the fast and reliable classification of glioma patients into one of six previously published stratified subtypes based on sets of extensively validated classifiers derived from hundreds of glioma transcriptomic profiles. Our tool utilizes a principle component analysis (PCA-based approach to generate a visual representation of the analyses, quantifies the confidence of the underlying subtype assessment and presents results as a printable PDF file. GliomaPredict tool is implemented as a plugin application for the widely-used GenePattern framework. Conclusions GliomaPredict provides a user-friendly, clinically applicable novel platform for instantly assigning gene expression-based subtype in patients with gliomas thereby aiding in clinical trial design and therapeutic decision-making. Implemented as a user-friendly diagnostic tool, we expect that in time GliomaPredict, and tools like it, will become routinely used in translational/clinical research and in the clinical care of patients with gliomas.

  6. Microglia-glioma cross-talk: a two way approach to new strategies against glioma.

    Science.gov (United States)

    Arcuri, Cataldo; Fioretti, Bernard; Bianchi, Roberta; Mecca, Carmen; Tubaro, Claudia; Beccari, Tommaso; Franciolini, Fabio; Giambanco, Ileana; Donato, Rosario

    2017-01-01

    Glioblastoma (GBM) is the most malignant and aggressive among primary brain tumors, characterized by very low life expectancy. In vivo, glioma and glioblastoma in particular contain large numbers of immune cells (myeloid cells) such as microglia and tumour-infiltrating macrophages (or glioma associated macrophages). These glioma-infiltrating myeloid cells comprise up to 30% of total tumor mass and have been suggested to play several roles in glioma progression including proliferation, survival, motility and immunosuppression. Although tumor microglia and macrophages can acquire proinflammatory (M1) phenotype being capable of releasing proinflammatory cytokines, phagocytosing and presenting antigens, their effector immune function in gliomas appears to be suppressed by the acquisition of an anti-inflammatory (M2) phenotype. In the present work we review the microglia-glioma interactions to highlight the close relationship between the two cell types and the factors that can influence their properties (chemokines, cytokines, S100B protein). A future therapeutic possibility might be to simultaneously targeting, for example with nanomedicine, glioma cells and microglia to push the microglia towards an antitumor phenotype (M1) and/or prevent glioma cells from "conditioning" by microglia.

  7. Known glioma risk loci are associated with glioma with a family history of brain tumours

    DEFF Research Database (Denmark)

    Melin, Beatrice; Dahlin, Anna M; Andersson, Ulrika

    2013-01-01

    Familial cancer can be used to leverage genetic association studies. Recent genome-wide association studies have reported independent associations between seven single nucleotide polymorphisms (SNPs) and risk of glioma. The aim of this study was to investigate whether glioma cases with a positive...

  8. 26 CFR 1.431(c)(6)-1 - Mortality tables used to determine current liability.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Mortality tables used to determine current liability. 1.431(c)(6)-1 Section 1.431(c)(6)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Certain Stock Options § 1.431(c)(6)-1 Mortality tables used to determine current...

  9. Genetically engineered rat gliomas: PDGF-driven tumor initiation and progression in tv-a transgenic rats recreate key features of human brain cancer.

    Science.gov (United States)

    Connolly, Nina P; Stokum, Jesse A; Schneider, Craig S; Ozawa, Tatsuya; Xu, Su; Galisteo, Rebeca; Castellani, Rudolph J; Kim, Anthony J; Simard, J Marc; Winkles, Jeffrey A; Holland, Eric C; Woodworth, Graeme F

    2017-01-01

    Previously rodent preclinical research in gliomas frequently involved implantation of cell lines such as C6 and 9L into the rat brain. More recently, mouse models have taken over, the genetic manipulability of the mouse allowing the creation of genetically accurate models outweighed the disadvantage of its smaller brain size that limited time allowed for tumor progression. Here we illustrate a method that allows glioma formation in the rat using the replication competent avian-like sarcoma (RCAS) virus / tumor virus receptor-A (tv-a) transgenic system of post-natal cell type-specific gene transfer. The RCAS/tv-a model has emerged as a particularly versatile and accurate modeling technology by enabling spatial, temporal, and cell type-specific control of individual gene transformations and providing de novo formed glial tumors with distinct molecular subtypes mirroring human GBM. Nestin promoter-driven tv-a (Ntv-a) transgenic Sprague-Dawley rat founder lines were created and RCAS PDGFA and p53 shRNA constructs were used to initiate intracranial brain tumor formation. Tumor formation and progression were confirmed and visualized by magnetic resonance imaging (MRI) and spectroscopy. The tumors were analyzed using histopathological and immunofluorescent techniques. All experimental animals developed large, heterogeneous brain tumors that closely resembled human GBM. Median survival was 92 days from tumor initiation and 62 days from the first point of tumor visualization on MRI. Each tumor-bearing animal showed time dependent evidence of malignant progression to high-grade glioma by MRI and neurological examination. Post-mortem tumor analysis demonstrated the presence of several key characteristics of human GBM, including high levels of tumor cell proliferation, pseudopalisading necrosis, microvascular proliferation, invasion of tumor cells into surrounding tissues, peri-tumoral reactive astrogliosis, lymphocyte infiltration, presence of numerous tumor

  10. Using of the surface plasmon resonance cytosensor for real-time and non-invasive monitoring of cellular effects in living C6 cells induced by PMA

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Developing novel instruments and technologies for spatio-temporal and dynamic measurements of the intricate cellular effects involving molecular translocation, signal transduction, and molecular interactions inside living cells is essential for the cell and molecular biology science. For the purpose of monitoring and investigating molecular events in living cells at real-time, the surface plasmon resonance based cytosensor (SBCS) for cell culturing and signal monitoring was established, and on the basis of it, the corresponding technology was also established by monitoring and analyzing SPR responses induced in rat C6 glioma cells by phorbol 12-myristate 13-acetate (PMA). The SPR signals induced by PMA in living C6 cells were significantly different from those groups without cells. These responses were strongly dependent on and saturable to the concentrations of PMA, and could be suppressed by the specific and potent PKC inhibitors, which indicated that the measured signal could be the reflection of the redistribution of intracellular components near the cell membrane triggered by the activation of PKC. This research provides a quantitative and non-invasive technique to study the spatio-temporal characteristics of the cellular effects in living cells at real-time. Furthermore, this technology could also be widely used in the basic research as well as applied realms, such as space effects evaluation, environmental safety assessment, biological weapon detection, cellular and molecular research, and drug screening.

  11. Water extract from the leaves of Withania somnifera protect RA differentiated C6 and IMR-32 cells against glutamate-induced excitotoxicity.

    Directory of Open Access Journals (Sweden)

    Hardeep Kataria

    Full Text Available Glutamate neurotoxicity has been implicated in stroke, head trauma, multiple sclerosis and neurodegenerative disorders. Search for herbal remedies that may possibly act as therapeutic agents is an active area of research to combat these diseases. The present study was designed to investigate the neuroprotective role of Withania somnifera (Ashwagandha, also known as Indian ginseng, against glutamate induced toxicity in the retinoic acid differentiated rat glioma (C6 and human neuroblastoma (IMR-32 cells. The neuroprotective activity of the Ashwagandha leaves derived water extract (ASH-WEX was evaluated. Cell viability and the expression of glial and neuronal cell differentiation markers was examined in glutamate challenged differentiated cells with and without the presence of ASH-WEX. We demonstrate that RA-differentiated C6 and IMR-32 cells, when exposed to glutamate, undergo loss of neural network and cell death that was accompanied by increase in the stress protein HSP70. ASH-WEX pre-treatment inhibited glutamate-induced cell death and was able to revert glutamate-induced changes in HSP70 to a large extent. Furthermore, the analysis on the neuronal plasticity marker NCAM (Neural cell adhesion molecule and its polysialylated form, PSA-NCAM revealed that ASH-WEX has therapeutic potential for prevention of neurodegeneration associated with glutamate-induced excitotoxicty.

  12. Fully differential cross sections for C6+single ionization of helium

    Institute of Scientific and Technical Information of China (English)

    Li Xia; Ma Xiao-Yan; Sun Shi-Yan; Jia Xiang-Fu

    2012-01-01

    The three-Coulomb-wave (3C) model is applied to study the single ionization of helium by 2 MeV/amu C6+impact.Fully differential cross sections (FDCS) are calculated in the scattering plane and the results are compared with experimental data and other theoretical predictions.It is shown that the 3C results of the recoil peak are in very good agreement with experimental observations,and variation of the position of the binary peak with increasing momentum transfer also conforms better to the experimental results.Furthermore,the contributions of different scattering amplitudes are discussed.It turns out that the cross sections are strongly influenced by the interference of these amplitudes.

  13. Imaging of a glioma using peripheral benzodiazepine receptor ligands

    Energy Technology Data Exchange (ETDEWEB)

    Starosta-Rubinstein, S.; Ciliax, B.J.; Penney, J.B.; McKeever, P.; Young, A.B.

    1987-02-01

    Two types of benzodiazepine receptors have been demonstrated in mammalian tissues, one which is localized on neuronal elements in brain and the other, on glial cells and in peripheral tissues such as kidney. In vivo administration of /sup 3/H-labeled PK 11195 (1-(2-chlorophenyl-N-methyl-N-(1-methylpropyl)-3-isoquinoline carboxamide) or (/sup 3/H)flunitrazepam with 5 mg of clonazepam per kg to rats with intracranial C6 gliomas resulted in high levels of tritiated-drug binding to the tumor as shown by quantitative autoradiography. Pharmacological studies indicated that the bound drugs labeled the peripheral benzodiazepine binding site. Binding to the peripheral benzodiazepine site was confirmed primarily to malignant cells with little binding to adjacent normal brain tissue or to necrotic tissue. Tumor cell binding was completely inhibited by preadministration of the peripheral benzodiazepine blocking agent PK 11195 at 5 mg/kg. The centrally selective benzodiazepine ligand clonazepam had no effect on PK 11195 binding to the tumor cells. When binding to other tumor cell lines grown in nude mice and nude athymic rats was evaluated, little or no peripheral benzodiazepine binding was detected on human pheochromocytoma (RN1) and neuroblastoma (SK-N-MC, SK-N-SH) tumor cells, respectively. However, high densities of peripheral benzodiazepine binding sites were observed on tumors derived from a human glioma cell line (ATCC HTB 14, U-87 MG). The presence of high concentrations of specific peripheral benzodiazepine receptors on glial tumors suggests that human primary central nervous system tumors could be imaged and diagnosed using peripheral benzodiazepine ligands labeled with positron- or gamma-emitting isotopes.

  14. TRIM28 as an independent prognostic marker plays critical roles in glioma progression.

    Science.gov (United States)

    Qi, Zeng-Xin; Cai, Jia-Jun; Chen, Ling-Chao; Yue, Qi; Gong, Yan; Yao, Yu; Mao, Ying

    2016-01-01

    Tripartite motif (TRIM) proteins are involved in tumorigenesis. Here, we examined the expression, biological function, and clinical significance of tripartite motif containing 28 (TRIM28) in glioma, a locally aggressive brain tumor. First, TRIM28 expression was significantly higher in glioma (n = 138) than in non-glioma controls (n = 6). TRIM28 expression was positively correlated with tumor malignancy, and associated with poor overall survival (OS) and progression-free survival (PFS). Notably, TRIM28 expression was negatively correlated with p21 expression in patients with glioblastoma multiforme (GBM). A multivariate analysis that included relevant measures indicated that high TRIM28 expression is an independent prognostic factor for poor OS and PFS in GBM patients. In experiments with cultured glioma cells, down-regulating TRIM28 with shRNA increased p21 expression, and induced cell cycle arrest at the G1 phase. In a xenograft model, down-regulating TRIM28 suppressed tumor growth. These results indicate that over-expression of TRIM28 is associated with poor outcome in glioma patients.

  15. KLF8 Promotes Temozolomide Resistance in Glioma Cells via β-Catenin Activation

    Directory of Open Access Journals (Sweden)

    Guo Yu

    2016-04-01

    Full Text Available Background/Aims: The transcription factor Krüppel-like factor (KLF 8 plays important roles in tumorigenesis and tumor metastasis. However, the relationship between KLF8 and glioma cell chemoresistance is not known. Methods: The effects of KLF8 on glioma cell proliferation, apoptosis and chemosensitivity to temozolomide (TMZ were analyzed by Cell Counting Kit 8 assay and flow cytometry assay. A xenograft model was used to study the effect of KLF8 on tumor growth and sensitivity to TMZ. Results: We found that in the absence of KLF8, glioma cells showed greater sensitivity to TMZ, resulting in the inhibition of cell growth and enhanced apoptosis. KLF8 overexpression had the opposite effect; that is, cell resistance to TMZ was increased, which was associated with β-catenin activation. Conclusion: Taken together, these data suggest that KLF8 modulates glioma cell resistance to TMZ via activation of β-catenin; therefore, therapies that inhibit KLF8 levels in glioma can enhance the efficacy of TMZ treatment.

  16. Characterization and Comparison of Cancer Stem Cells in Human and Canine Glioma Cell Lines

    Directory of Open Access Journals (Sweden)

    Thomas Clements

    2012-01-01

    Full Text Available Gliomas are among the most common and malignantforms of primary brain tumors that occur naturally inhumans. They represent about 33% of brain tumorsand 80% of malignant brain tumors. Gliomas alsospontaneously arise in specific breeds in the canine family.Canine gliomas are histologically similar to human gliomaand have similar presentation and response to treatmentin the clinic. A comparison of canine and human gliomascould prove to be invaluable, because the acceptedrodent model has limitations when testing therapies andidentifying targets. Our goal is to obtain global proteinexpression and metabolic profiles of different classificationand grades of human and canine glioma, in order toidentify and compare the tumor survival strategies in bothsystems. Toward this end, we harvested and cultured cellsfrom a naturally occurring grade-3 oligodendrogliomatumor that was isolated from a canine patient at the PurdueUniversity Veterinary Teaching Hospital. Similar to cellsfrom human glioma, these cells formed neurosphereswhen cultured in serum free media in the presence of FGFand EGF. The cells were also sensitive to plating densityand oxygen concentrations.This work was supported by the National Institutes ofHealth, National Cancer Institute R25CA128770 CancerPrevention Internship Program administered by theOncological Sciences Center and the Discovery LearningResearch Center at Purdue University. This work wasalso supported by Showalter Research Foundation and aCollege of Technology Seed Grant.

  17. Epidermal growth factor (EGF) as a potential targeting agent for delivery of boron to malignant gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Capala, J.; Barth, R.F.; Adams, D.M.; Bailey, M.Q.; Soloway, A.H. [Ohio State Univ., Columbus, OH (United States); Carlsson, J. [Uppsala Univ. (Sweden). Dept. of Radiation Sciences

    1994-12-31

    The majority of high grade gliomas express an amplified epidermal growth factor receptor (EGFR) gene, and this often is associated with an increase in cell surface receptor expression. The rapid internalization and degradation of EGF-EGFR complexes, as well as their high affinity make EGF a potential targeting agent for delivery of {sup 10}B to tumor cells with an amplified number of EGFR. Human glioma cells can expresses as many as 10{sup 5} {minus}10{sup 6} EGF receptors per cell, and if these could be saturated with boronated EGF, then > 10{sup 8} boron atoms would be delivered per cell. Since EGF has a comparatively low molecular weight ({approximately} 6 kD), this has allowed us to construct relatively small bioconjugates containing {approximately} 900 boron atoms per EGF molecule{sup 3}, which also had high affinity for EGFR on tumor cells. In the present study, the feasibility of using EGF receptors as a potential target for therapy of gliomas was investigated by in vivo scintigraphic studies using {sup 131}I{minus} or {sup 99m}{Tc}-labeled EGF in a rat brain tumor model. Our results indicate that intratumorally delivered boron- EGF conjugates might be useful for targeting EGFR on glioma cells if the boron containing moiety of the conjugates persisted intracellularly. Further studies are required, however, to determine if this approach can be used for BNCT of the rat glioma.

  18. ABCG1 maintains high-grade glioma survival in vitro and in vivo.

    Science.gov (United States)

    Chen, Yi-Hsien; Cimino, Patrick J; Luo, Jingqin; Dahiya, Sonika; Gutmann, David H

    2016-04-26

    The overall survival for adults with malignant glioma (glioblastoma) remains poor despite advances in radiation and chemotherapy. One of the mechanisms by which cancer cells develop relative resistance to treatment is through de-regulation of endoplasmic reticulum (ER) homeostasis. We have recently shown that ABCG1, an ATP-binding cassette transporter, maintains ER homeostasis and suppresses ER stress-induced apoptosis in low-grade glioma. Herein, we demonstrate that ABCG1 expression is increased in human adult glioblastoma, where it correlates with poor survival in individuals with the mesenchymal subtype. Leveraging a mouse model of mesenchymal glioblastoma (NPcis), shRNA-mediated Abcg1 knockdown (KD) increased CHOP ER stress protein expression and resulted in greater NPcis glioma cell death in vitro. Moreover, Abcg1 KD reduced NPcis glioma growth and increased mouse survival in vivo. Collectively, these results demonstrate that ABCG1 is critical for malignant glioma cell survival, and might serve as a future therapeutic target for these deadly brain cancers.

  19. Family history of cancer in benign brain tumor subtypes versus gliomas

    Directory of Open Access Journals (Sweden)

    Quinn eOstrom

    2012-02-01

    Full Text Available Purpose: Family history is associated with gliomas, but this association has not ben established for benign brain tumors. Using information from newly diagnosed primary brain tumor patients, we describe patterns of family cancer histories in patients with benign brain tumors and compare those to patients with gliomas. Methods: Newly diagnosed primary brain tumor patients were identified as part of the Ohio Brain Tumor Study (OBTS. Each patient was asked to participate in a telephone interview about personal medical history, family history of cancer, and other exposures. Information was available from 33 acoustic neuroma (65%, 78 meningioma (65%, 49 pituitary adenoma (73.1% and 152 glioma patients (58.2%. The association between family history of cancer and each subtype was compared with gliomas using unconditional logistic regression models generating odds ratios (ORs and 95% confidence intervals (95% CI. Results: There was no significant difference in family history of cancer between patients with glioma and benign subtypes. Conclusions: The results suggest that benign brain tumor may have an association with family history of cancer. More studies are warranted to disentangle the potential genetic and/or environmental causes for these diseases.

  20. Molecular Diagnostics of Gliomas Using Next Generation Sequencing of a Glioma-Tailored Gene Panel.

    Science.gov (United States)

    Zacher, Angela; Kaulich, Kerstin; Stepanow, Stefanie; Wolter, Marietta; Köhrer, Karl; Felsberg, Jörg; Malzkorn, Bastian; Reifenberger, Guido

    2017-03-01

    Current classification of gliomas is based on histological criteria according to the World Health Organization (WHO) classification of tumors of the central nervous system. Over the past years, characteristic genetic profiles have been identified in various glioma types. These can refine tumor diagnostics and provide important prognostic and predictive information. We report on the establishment and validation of gene panel next generation sequencing (NGS) for the molecular diagnostics of gliomas. We designed a glioma-tailored gene panel covering 660 amplicons derived from 20 genes frequently aberrant in different glioma types. Sensitivity and specificity of glioma gene panel NGS for detection of DNA sequence variants and copy number changes were validated by single gene analyses. NGS-based mutation detection was optimized for application on formalin-fixed paraffin-embedded tissue specimens including small stereotactic biopsy samples. NGS data obtained in a retrospective analysis of 121 gliomas allowed for their molecular classification into distinct biological groups, including (i) isocitrate dehydrogenase gene (IDH) 1 or 2 mutant astrocytic gliomas with frequent α-thalassemia/mental retardation syndrome X-linked (ATRX) and tumor protein p53 (TP53) gene mutations, (ii) IDH mutant oligodendroglial tumors with 1p/19q codeletion, telomerase reverse transcriptase (TERT) promoter mutation and frequent Drosophila homolog of capicua (CIC) gene mutation, as well as (iii) IDH wildtype glioblastomas with frequent TERT promoter mutation, phosphatase and tensin homolog (PTEN) mutation and/or epidermal growth factor receptor (EGFR) amplification. Oligoastrocytic gliomas were genetically assigned to either of these groups. Our findings implicate gene panel NGS as a promising diagnostic technique that may facilitate integrated histological and molecular glioma classification.

  1. Number of Spanning Trees of Circulant Graphs C6n and their Applications

    Directory of Open Access Journals (Sweden)

    S. N. Daoud

    2012-01-01

    Full Text Available Problem statement: The number of spanning trees of a graph G is usually denoted by τ(G. A circulant graph with n vertices and k jumps is Cn (a1,…..,ak. Approach: In this study the number τ(G of spanning trees of the circulant graphs C6n with some non-fixed jumps such as C6n (1, n, C6n (1, n, 2n, C6n (1, n, 3n, C6n (1, 2n 3n, C6n (1, n, 2n, 3n, are evaluated using Chebyshev polynomials. A large number of theorems of number of the spanning trees of circulate graphs C12n are obtained. Results: The number τ(G of spanning trees of the circulant graphs C6n(1, n, C6n(1, n, 2n, C6n(1, n, 3n, C6n(1, 2n, 3n, C6n(1, n, 2n, 3n, C12n(1, 2n, 3n, C12n(1, 3n, 6n, C12n(1, 3n, 4n, C12n(1, 2n, 3n, 4n, C12n(1, 2n, 3n, 6n, C12n(1, 3n, 4n, 6n and C12n(1, 2n, 3n, 4n, 6n are evaluated. Conclusion: The number of spanning trees τ(G in graphs (networks is an important invariant. The evaluation of this number and analyzing its behavior is not only interesting from a mathematical (computational perspective, but also, it is an important measure of reliability of a network and designing electrical circuits. Some computationally hard problems such as the travelling salesman problem can be solved approximately by using spanning trees. Due to the high dependence of the network design and reliability on the graph theory we introduced the following important theorems and their proofs.

  2. Electron Transfer Reaction between M-C6H6 and M+-C6H6 Complexes in the Gas Phase: Density Functional Theory Study

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    DFT/BLYP method is used to theoretically investigate the electron transfer (ET) reactions between M (Li, Na, Mg)-C6H6 and M+-C6H6 complexes in the gas phase. The geometry optimization of the precursor complexes and the transition state in the process of ET reaction was performed at 6-31G basis set level. The activation energy, the coupling matrix element and the rate constant of the ET reaction are calculated at semi-quantitative level.

  3. Volumetric Properties of the Mixture Benzene C6H6 + C6H10O Cyclohexanone (VMSD1511, LB4829_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Benzene C6H6 + C6H10O Cyclohexanone (VMSD1511, LB4829_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  4. Heat of Mixing and Solution of Cyclohexanone C6H10O + C6H12O Cyclohexanol (HMSD1121, LB4187_H)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Heat of Mixing and Solution of Cyclohexanone C6H10O + C6H12O Cyclohexanol (HMSD1121, LB4187_H)' providing data from direct calorimetric measurement of molar excess enthalpy at variable mole fraction and constant pressure and temperature.

  5. Volumetric Properties of the Mixture Benzene C6H6 + C6H10O Cyclohexanone (VMSD1212, LB4824_V)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Benzene C6H6 + C6H10O Cyclohexanone (VMSD1212, LB4824_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  6. Volumetric Properties of the Mixture Benzene C6H6 + C6H10O Cyclohexanone (VMSD1111, LB4819_V0029

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Benzene C6H6 + C6H10O Cyclohexanone (VMSD1111, LB4819_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  7. Vapor-Liquid Equilibrium in the Mixture Cyclohexanone C6H10O + C6H12O Cyclohexanol (EVLM1111, LB5657_E)

    Science.gov (United States)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Vapor-Liquid Equilibrium in the Mixture Cyclohexanone C6H10O + C6H12O Cyclohexanol (EVLM1111, LB5657_E)' providing data from direct measurement of pressure at variable mole fraction in liquid phase and constant temperature.

  8. Evidence from a large-scale meta-analysis indicates eczema reduces the incidence of glioma

    Science.gov (United States)

    Cao, Chao; Dong, Jing; Chu, Yudong; He, Guijuan; Xu, Zhiwei

    2016-01-01

    We investigated the relationship between eczema and the risk of primary glioma. Relevant studies were selected through electronic searches of PubMed and EMBASE. A meta-analysis of 12 case-control studies and one cohort study was performed. A fixed effect model was applied to analyze 13 studies consisting of 10,897 glioma cases and 56,081 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the associations. The data demonstrate that eczema significantly reduces the risk of glioma (OR = 0.69, 95% CI = 0.61–0.78, P < 0.001). Additional studies with larger patient cohorts are required to validate our findings. PMID:27566584

  9. 26 CFR 1.381(c)(6)-1 - Depreciation method.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Depreciation method. 1.381(c)(6)-1 Section 1.381... (CONTINUED) INCOME TAXES Insolvency Reorganizations § 1.381(c)(6)-1 Depreciation method. (a) Carryover... corporation which computes its allowance for the depreciation of the property under section 167(b)(2), (3),...

  10. Enzymatic Hydrolysis of Pretreated Fibre Pressed Oil Palm Frond by using Sacchariseb C6

    Science.gov (United States)

    Hashim, F. S.; Yussof, H. W.; Zahari, M. A. K. M.; Rahman, R. A.; Illias, R. M.

    2017-06-01

    Enzymatic hydrolysis becomes a prominent technology for conversion of cellulosic biomass to its glucose monomers that requires an action of cellulolytic enzymes in a sequential and synergistic manner. In this study, the effect of agitation speed, glucan loading, enzyme loading, temperature and reaction time on the production of glucose from fibre pressed oil palm frond (FPOPF) during enzymatic hydrolysis was screened by a half factorial design 25-1 using Response Surface Methodology (RSM). The FPOPF sample was first delignified by alkaline pretreatment at 4.42 (w/v) sodium hydroxide for an hour prior to enzymatic hydrolysis using commercial cellulase enzyme, Sacchariseb C6. The effect of enzymatic hydrolysis on the structural of FPOPF has been evaluated by Scanning Electron Microscopy (SEM) analysis. Characterization of raw FPOPF comprised of 4.5 extractives, 40.7 glucan, 26.1 xylan, 26.2 lignin and 1.8 ash, whereas for pretreated FPOPF gave 0.3 extractives, 61.4 glucan, 20.4 xylan, 13.3 lignin and 1.3 ash. From this study, it was found that the best enzymatic hydrolysis condition yielded 33.01 ± 0.73 g/L of glucose when performed at 200 rpm of agitation speed, 60 FPU/mL of enzyme loading, 4 (w/w) of glucan loading, temperature at 55 □ and 72 hours of reaction time. The model obtained was significant with p-value variance (ANOVA). The coefficient of determination (R2) from ANOVA study was 0.9959. Overall, it can be concluded that addition of Sacchariseb C6 during enzymatic hydrolysis from pretreated FPOPF produce high amount of glucose that enhances it potential for industrial application. This glucose can be further used to produce high-value products.

  11. Cellular senescence induced by prolonged subculture adversely affects glutamate uptake in C6 lineage.

    Science.gov (United States)

    Pereira, Mery Stéfani Leivas; Zenki, Kamila; Cavalheiro, Marcela Mendonça; Thomé, Chairini Cássia; Filippi-Chiela, Eduardo Cremonese; Lenz, Guido; de Souza, Diogo Onofre Gomes; de Oliveira, Diogo Losch

    2014-05-01

    Several researchers have recently used C6 cells to evaluate functional properties of high-affinity glutamate transporters. However, it has been demonstrated that this lineage suffers several morphological and biochemical alterations according to the number of passages in culture. Currently, there are no reports showing whether functional properties of high-affinity glutamate transporters comply with these sub culturing-dependent modifications. The present study aimed to compare the functional properties of high-affinity glutamate transporters expressed in early (EPC6) and late (LPC6) passage C6 cells through a detailed pharmacological and biochemical characterization. Between 60-180 min of L-[(3)H]glu incubation, LPC6 presented an intracellular [(3)H] 55% lower than EPC6. Both cultures showed a time-dependent increase of intracellular [(3)H] reaching maximal levels at 120 min. Cultures incubated with D-[(3)H]asp showed a time-dependent increase of [(3)H] until 180 min. Moreover, LPC6 have a D-[(3)H]asp-derived intracellular [(3)H] 30-45% lower than EPC6 until 120 min. Only EAAT3 was immunodetected in cultures and its total content was equal between them. PMA-stimulated EAAT3 trafficking to membrane increased 50% of L-[(3)H]glu-derived intracellular [(3)H] in EPC6 and had no effect in LPC6. LPC6 displayed characteristics that resemble senescence, such as high β-Gal staining, cell enlargement and increase of large and regular nuclei. Our results demonstrated that LPC6 exhibited glutamate uptake impairment, which may have occurred due to its inability to mobilize EAAT3 to cell membrane. This profile might be related to senescent process observed in this culture. Our results suggest that LPC6 cells are an inappropriate glial cellular model to investigate the functional properties of high-affinity glutamate transporters.

  12. Glioma-related edema: new insight into molecular mechanisms and their clinical implications

    Institute of Scientific and Technical Information of China (English)

    Zhi-Xiong Lin

    2013-01-01

    Glioma-related edema (GRE) is a significant contributor to morbidity and mortality from glioma.GRE is a complicated process involving not only peritumoral edema but also the water content of the tumor body.In terms of etiology,this condition derives from both GRE in the untreated state and GRE secondary to clinical intervention,and different cell types contribute to distinct components of GRE.Peritumoral edema was previously believed to loosen glioma tissue,facilitating tumor-cell invasion;however,the nutrition hypothesis of the tumor microecosystem suggests that tumor cells invade for the sake of nutrition.Edema is the pathologic consequence of the reconstructed trophic linkage within the tumor microecosystem.Glioma cells induce peritumoral brain edema via an active process that supplies a suitable niche for peritumoral invasive cells,suggesting that glioma-related peritumoral brain edema is determined by the invasive property of tumor cells.There are differences between pivotal molecular events and reactive molecular events in the development of GRE.Molecular therapy should target the former,as targeting reactive molecular events will produce undesired or even adverse results.At present,brain glioma angiogenesis models have not been translated into a new understanding of the features of brain images.The effect of these models on peritumoral brain edema is unclear.Clinical approaches should be transformed on the basis of new knowledge of the molecular mechanism underlying GRE.Exploring clinical assessment methods,optimizing the existing control strategy of GRE,and simultaneously developing new treatments are essential.

  13. 脑胶质瘤治疗中自由基清除剂的价值%Influence of free radical on the treatment for glioma

    Institute of Scientific and Technical Information of China (English)

    赵心同; 赵洪洋; 姚东晓; 王海均

    2011-01-01

    目的:探讨自由基清除剂依达拉奉(EDA)对肿瘤大小的影响及在肿瘤治疗中的价值.方法:MTT比色法测定EDA对胶质瘤细胞的影响.采用立体定向技术将C6脑胶质瘤细胞接种于大鼠右侧尾状核,建立脑胶质瘤模型,将荷瘤大鼠随机分为EDA高和低剂量组、对照组及空白组4组.空白组用来测定肿瘤组织与正常脑组织中超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量,其他组用EDA或生理盐水干预,观察对肿瘤大小的影响.结果:浓度为1×10-3、1×10-4、1×10-5和1×10-6mol/L的EDA作用48 h后,细胞的增殖率分别为8.3%、13.2%、21.9%和30.6%,呈浓度依赖性.与正常脑组织相比,胶质瘤组织中SOD活性较低,而MDA含量较高,差异均有统计学意义,P=0.000.EDA高剂量组平均肿瘤体积最大,其次为EDA低剂量组,对照组最小.3组荷瘤大鼠肿瘤平均体积差异有统计学意义(F=5.863,P=0.008),EDA高剂量组与其他2组比较差异均有统计学意义,但EDA低剂量组与对照组间差异无统计学意义.结论:自由基清除剂EDA能够促进肿瘤的生长,自由基在肿瘤的综合治疗中有潜在的价值.%OBJECTIVE: To study the influence of edaravone on tumor size, and explore the value of free radicals in the treatment for glioma.METHODS: MTT assay was used to detect the influence of EDA on glioma cells.The suspention of rat C6 glioma cells was stereotaxically injected into right caudate to establish rat C6 glioma model.The rats were randomly classified into 4 groups (EDA group in high dose, EDA group in low dose, control group and blank group).SOD activity and the content of MDA were detected in blank group.Other groups were treated with EDA or normal saline in order to observe their influence on tumor size.RESULTS: After being treated with EDA in dose of 1 × 10-3 , 1 ×10-4 , 1 × 10-5 , 1 × 10-6 mol/L for 48 hours, the proliferation rate of glioma cells was 8.3%, 13.2%, 21.9%, 30.6% respectively

  14. Combination of vatalanib and a 20-HETE synthesis inhibitor results in decreased tumor growth in an animal model of human glioma

    Directory of Open Access Journals (Sweden)

    Shankar A

    2016-03-01

    Full Text Available Adarsh Shankar,1 Thaiz F Borin,2 Asm Iskander,1 Nadimpalli RS Varma,3 Bhagelu R Achyut,1 Meenu Jain,1 Tom Mikkelsen,4 Austin M Guo,5 Wilson B Chwang,3 James R Ewing,6 Hassan Bagher-Ebadian,6 Ali S Arbab11Tumor Angiogenesis Laboratory, Cancer Center, Georgia Regents University, Augusta, GA, USA; 2Laboratory of Molecular Investigation of Cancer (LIMC, Faculty of Medicine of Sao Jose do Rio Preto, Sao Jose do Rio Preto, Brazil; 3Department of Radiology, Cellular and Molecular Imaging Laboratory, 4Department of Neurosurgery, Henry Ford Health System, Detroit, MI, 5Department of Pharmacology, New York Medical College, Valhalla, NY, 6Department of Neurology and Radiology, Henry Ford Health System, Detroit, MI, USA Background: Due to the hypervascular nature of glioblastoma (GBM, antiangiogenic treatments, such as vatalanib, have been added as an adjuvant to control angiogenesis and tumor growth. However, evidence of progressive tumor growth and resistance to antiangiogenic treatment has been observed. To counter the unwanted effect of vatalanib on GBM growth, we have added a new agent known as N-hydroxy-N'-(4-butyl-2 methylphenylformamidine (HET0016, which is a selective inhibitor of 20-hydroxyeicosatetraenoic acid (20-HETE synthesis. The aims of the studies were to determine 1 whether the addition of HET0016 can attenuate the unwanted effect of vatalanib on tumor growth and 2 whether the treatment schedule would have a crucial impact on controlling GBM.Methods: U251 human glioma cells (4×105 were implanted orthotopically. Two different treatment schedules were investigated. Treatment starting on day 8 (8–21 days treatment of the tumor implantation was to mimic treatment following detection of tumor, where tumor would have hypoxic microenvironment and well-developed neovascularization. Drug treatment starting on the same day of tumor implantation (0–21 days treatment was to mimic cases following radiation therapy or surgery. There were four

  15. Enhanced invasion in vitro and the distribution patterns in vivo of CD133+ glioma stem cells

    Institute of Scientific and Technical Information of China (English)

    YU Sheng-ping; YANG Xue-jun; ZHANG Bin; MING Hao-lang; CHEN Cong; REN Bing-cheng; LIU Zhi-feng; LIU Bin

    2011-01-01

    Background Recent studies have suggested that cancer stem cells cause tumor recurrence based on their resistance to radiotherapy and chemotherapy.Although the highly invasive nature of glioblastoma cells is also implicated in the failure of current therapies,it is not clear whether cancer stem cells are involved in invasiveness.This study aimed to assess invasive ability of glioma stem cells (GSCs) derived from C6 glioma cell line and the distribution patterns of GSCs in Sprague-Dawley (SD) rat brain tumor.Methods Serum-free medium culture and magnetic isolation were used to gain purely CD133+ GSCs.The invasive stem cell markers and luxol fast blue staining for white matter tracts were performed to show the distribution patterns of GSCs in brain tumor of rats and the relationship among GSCs,vessels,and white matter tracts.The results of matrigel invasion assay were estimated using the Student's t test and the analysis of Western blotting was performed using the one-way analysis of variance (ANOVA) test.Results CD133+GSCs(number:85.3±4.1)were significantly more invasive in vitro than matched CD133- cells(number:25.9±3.1) (t=14.5,P <0.005).GSCs invaded into the brain diffusely and located in perivascular niche of tumor-brain interface or resided within perivascular niche next to white fiber tracts.The polarity of glioma cells containing GSCs was parallel to the white matter tracts.Conclusions Our data suggest that CD133+ GSCs exhibit more aggressive invasion in vitro and GSCs in vivo probably disseminate along the long axis of blood vessels and transit through the white matter tracts.The therapies targeting GSCs invasion combined with traditional glioblastoma multiforme therapeutic paradigms might be a new approach for avoiding malignant glioma recurrence.

  16. Influences of surface coatings and components of FePt nanoparticles on the suppression of glioma cell proliferation

    Directory of Open Access Journals (Sweden)

    Sun H

    2012-07-01

    Full Text Available Haiming Sun,1,* Xiaohui Chen,2,* Dan Chen,1 Mingyan Dong,1 Xinning Fu,1 Qian Li,1 Xi Liu,1 Qingzhi Wu,1 Tong Qiu,1 Tao Wan,1 Shipu Li11State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and Biomedical Materials and Engineering Center, Wuhan University of Technology, Wuhan, China; 2Department of Prosthetics, School of Stomatology, Wuhan University, Wuhan, China*Both authors contributed equally to this workAbstract: Malignant gliomas are primary brain tumors with high rates of morbidity and mortality; they are the fourth most common cause of cancer death. Novel diagnostic and therapeutic techniques based on nanomaterials provide promising options in the treatment of malignant gliomas. In order to evaluate the potential of FePt nanoparticles (NPs for malignant glioma therapy, FePt NPs with different surface coatings and components were tunably synthesized using oleic acid/oleylamine (OA/OA and cysteines (Cys as the capping agents, respectively. The samples were characterized using X-ray diffraction, transmission electron microscopy (TEM, X-ray photon spectroscopy, Fourier transform infrared spectroscopy, atomic absorption spectrum, and zeta potential. The influence of the surface coatings and components of the FePt NPs on the proliferation of glioma cells was assessed through MTT assay and TEM observation using three typical glioma cell lines (glioma U251 cells, astrocytoma U87 cells, and neuroglioma H4 cells as in vitro models. The results showed that the proliferation of glioma cells was significantly suppressed by lipophilic FePt-OA/OA NPs in a time- and/or dose-dependent manner, while no or low cytotoxic effects were detected in the case of hydrophilic FePt-Cys NPs. The IC50 value of FePt-OA/OA NPs on the three glioma cell lines was approximately 5–10 µg mL-1 after 24 hours’ incubation. Although the cellular uptake of FePt NPs was confirmed regardless of the surface coatings and components of the FePt NPs

  17. Selective induction of apoptosis in glioma tumour cells by a Gynostemma pentaphyllum extract.

    Science.gov (United States)

    Schild, L; Chen, B H; Makarov, P; Kattengell, K; Heinitz, K; Keilhoff, G

    2010-07-01

    At low concentration H(2)O(2) is an important signal molecule in proliferation of tumour cells. We report about a study investigating the effect of an ethanolic extract from Gynostemma pentaphyllum on proliferation of C6 glioma tumour cells and cellular H(2)O(2) concentration. The proliferation of these cells was maximal at about 1 muM extracellular H(2)O(2). HPLC-finger prints of the extract revealed a set of saponines as essential components. In C6 glioma cells the extract caused increase in super oxide dismutase (SOD) activity, in the amount of SOD protein, and in cellular H(2)O(2) concentration. It inhibited cell proliferation and induced activation of caspase 3 as indication of apoptosis. No effect of the extract was observed on the proliferation of astrocytes of a primary cell culture. From these findings we suggest that the ethanolic extract from Gynostemma pentaphyllum may selectively shift the H(2)O(2) concentration to toxic levels exclusively in tumour cells due to increased SOD activity. It may have a high potency in cancer therapy and cancer prophylaxis. (c) 2010 Elsevier GmbH. All rights reserved.

  18. Molecular Therapeutic Targets for Glioma Angiogenesis

    Directory of Open Access Journals (Sweden)

    Shingo Takano

    2010-01-01

    Full Text Available Due to the prominent angiogenesis that occurs in malignant glioma, antiangiogenic therapy has been attempted. There have been several molecular targets that are specific to malignant gliomas, as well as more broadly in systemic cancers. In this review, I will focus on some topics related to molecular therapeutic targets for glioma angiogenesis. First, important angiogenic factors that could be considered molecular targets are VEGF, VEGF-induced proteins on endothelial cells, tissue factor, osteopontin, v3 integrin, and thymidine phosphorylase as well as endogenous inhibitors, soluble Flt1, and thrombospondin 1. Second, hypoxic areas are also decreased by metronomic CPT11 treatment as well as temozolomide. Third, glioma-derived endothelial cells that are genetically and functionally distinct from normal endothelial cells should be targeted, for example, with SDF-1 and CXCR7 chemokine. Fourth, endothelial progenitor cells (EPCs likely contribute towards glioma angiogenesis in the brain and could be useful as a drug delivery tool. Finally, blockade of delta-like 4 (Dll4 results in a nonfunctioning vasculature and could be another important target distinct from VEGF.

  19. Genetic characterization of adult infratentorial gliomas.

    Science.gov (United States)

    Miwa, Tomoru; Hirose, Yuichi; Sasaki, Hikaru; Ikeda, Eiji; Yoshida, Kazunari; Kawase, Takeshi

    2009-02-01

    Adult infratentorial gliomas are rare and have not been well studied. We therefore conducted genetic analysis of those tumors to see if there was any characteristic that could be relevant in clinical management and understanding of tumorigenesis. Nineteen adult infratentorial gliomas were analyzed for chromosomal aberration by comparative genomic hybridization, and for expression of p53 and epidermal growth factor receptor (EGFR) by immunohistochemistry. The most frequent chromosomal aberration was the gain of 7p, and five of the seven cerebellar or fourth ventricle malignant gliomas had that aberration. However, the gain of 7q, the characteristic abnormality of supratentorial astrocytomas commonly associated with the gaining of 7p, was observed only in 1 of 11 adult infratentorial astrocytic tumors. Combined losses of 1p and 19q, the genetic hallmark of oligodendroglioma, were not observed. Results of immunohistochemistry of p53 and EGFR were comparable to those reported in supratentorial gliomas. Our findings might suggest the presence of distinct tumorigenic pathway in adult infratentorial gliomas.

  20. Sensitivity of Interstitial combined Chemotherapy against Glioma

    Institute of Scientific and Technical Information of China (English)

    WANG Ming-sheng; LIN Jian-ying; ZHOU Guo-sheng; ZHANG Xin-zhong

    2006-01-01

    Objective To investigate the inhibitory effects of combination chemotherapy of Carboplatin(CBP) ,Teniposide (Vm-26) ,Methasquin(MTX),and Nimodipine(NIM) on glioma,and to explore the sensitivity of glioma cells to different treatment regimens so as to provide some clues for clinical usage of interstitial combination chemotherapy. Methods MTT assay and 3H-TdR incorporation assay were performed to evaluate the inhibitory effects upon the proliferation of glioma cells,and to compare the sensitivity of glioma cells to administration of CBP,Vm-26, MTX, and NIM with that of the administration of CBP + NIM, Vm-26 + NIM, MTX + NIM, CBP + Vm-26 + MTX, or CBP + Vm-26 + MTX + NIM respectively. Results The inhibition rate of CBP + Vm-26 + MTX + NIM combination administration against glioma cells was 96.64%,which was higher than that of CBP + NIM (69.03%), Vm-26 + NIM (71.53%), MTX + NIM (52. 75% ), CBP + Vm-26 + MTX(78.59%)(P<0.01),and the dosage of CBP,Vm-26,and MTX was declined to 1/10 ~ 1/100 that of respective use of CBP,Vm-26,and MTX. Conclusions The curative effects of combination administration of CBP,Vm-26, MTX, and NIM was much better than that of respective administration,suggesting a higher inhibition rate and a lower dosage use.

  1. [Chemotherapy of chiasmal gliomas in children].

    Science.gov (United States)

    Helcl, F

    1995-04-01

    Chiasmal gliomas are rare tumors occurring predominantly in childhood. Their optimal treatment is still controversial. In the past only neurosurgeons (performing partial or subtotal removal of the tumor, biopsy or shunting procedure in hydrocephalus) and radiotherapeutists participated in their treatment. In the middle of the eighties there was only a single article dealing with chemotherapy of these tumors (Rosenstock, 1985). Since that time there was an increased number of articles about harmful effects of radiotherapy on the developing child's brain. Neurosurgeons are aware that they will not solve this problem alone. During the past 7 years we have observed gradual retreat from radiotherapy and an inclination to combined chemotherapy of the chiasmal gliomas in children. The author has been engaged in the research of this clinical entity for more than 10 years and he offers to readers a summary of the contemporary knowledge about chemotherapy of chiasmal gliomas in children. Despite the fact that there is lacking experience with long-term survivors after chemotherapy, which is extremely important especially in this disease, the preliminary short-term results of combined chemotherapy of chiasmal gliomas in children are promising. Rapid development of chemistry and pharmacology in the last few years is promising for the discovery of further, more effective anti-tumor drugs. Their new combinations could improve present non-satisfactory results of treatment of chiasmal gliomas in children. (Ref. 25.)

  2. Powder Structure Solutions of the Compounds Potassium Phenoxide-Phenol: C(6)H(5)OK.xC(6)H(5)OH (x = 2, 3).

    Science.gov (United States)

    Dinnebier, R. E.; Pink, M.; Sieler, J.; Norby, P.; Stephens, P. W.

    1998-09-21

    We report the ab initio structure solutions of two solvent containing potassium phenoxides by high-resolution powder X-ray diffraction. Both compounds are of interest for the classification of the mechanism of Kolbe-Schmitt type reactions. C(6)H(5)OK.2C(6)H(5)OH crystallizes in space group Abm2, Z = 4, with unit cell parameters a = 10.12458(4) Å, b = 21.2413(1) Å, c = 7.89784(3) Å. C(6)H(5)OK.3C(6)H(5)OH crystallizes in space group Pbca, Z = 8, with unit cell parameters a = 22.7713(1) Å, b = 25.4479(2) Å, c = 7.75549(4) Å. Both compounds show polymeric zigzag chains [K([6])O(2)([2])O([1])pi(phenyl)([1])] aligned along the c-axis. The coordination of the potassium ions is similar for both compounds. They lie at the center of distorted octahedra of five oxygen atoms and one phenyl ring, which donates its pi electrons. The distortion decreases as the number of free phenol increases.

  3. Glioma cells on the run – the migratory transcriptome of 10 human glioma cell lines

    Directory of Open Access Journals (Sweden)

    Holz David

    2008-01-01

    Full Text Available Abstract Background Glioblastoma multiforme (GBM is the most common primary intracranial tumor and despite recent advances in treatment regimens, prognosis for affected patients remains poor. Active cell migration and invasion of GBM cells ultimately lead to ubiquitous tumor recurrence and patient death. To further understand the genetic mechanisms underlying the ability of glioma cells to migrate, we compared the matched transcriptional profiles of migratory and stationary populations of human glioma cells. Using a monolayer radial migration assay, motile and stationary cell populations from seven human long term glioma cell lines and three primary GBM cultures were isolated and prepared for expression analysis. Results Gene expression signatures of stationary and migratory populations across all cell lines were identified using a pattern recognition approach that integrates a priori knowledge with expression data. Principal component analysis (PCA revealed two discriminating patterns between migrating and stationary glioma cells: i global down-regulation and ii global up-regulation profiles that were used in a proband-based rule function implemented in GABRIEL to find subsets of genes having similar expression patterns. Genes with up-regulation pattern in migrating glioma cells were found to be overexpressed in 75% of human GBM biopsy specimens compared to normal brain. A 22 gene signature capable of classifying glioma cultures based on their migration rate was developed. Fidelity of this discovery algorithm was assessed by validation of the invasion candidate gene, connective tissue growth factor (CTGF. siRNA mediated knockdown yielded reduced in vitro migration and ex vivo invasion; immunohistochemistry on glioma invasion tissue microarray confirmed up-regulation of CTGF in invasive glioma cells. Conclusion Gene expression profiling of migratory glioma cells induced to disperse in vitro affords discovery of genomic signatures; selected

  4. Anaerobic biodegradation of 13C6-phenol: Analysis of bacteria population involved in two different degradation kinetics

    OpenAIRE

    Hoyos Hernandez, C.; Limam, I.; Desmond, E.; Bouchez, T.; Mazeas, L.

    2013-01-01

    International audience; Biodegradation of 13C6-phenol until mineralisation was observed under mesophilic and thermophilic conditions during the degradation of municipal solid waste. In Mesophilic conditions, as well as in thermophilic, two types of degradation kinetics were obtained. One follows a first order kinetic and the other follows a lag-phase model. The pyrosequencing analysis shows that in the fastest kinetic Clostridium sp. and Anaerobranca sp. were the microorganisms majorly presen...

  5. Inhibition of MMP14 potentiates the therapeutic effect of temozolomide and radiation in gliomas

    Science.gov (United States)

    Ulasov, Ilya; Thaci, Bart; Sarvaiya, Purvaba; Yi, Ruiyang; Guo, Donna; Auffinger, Brenda; Pytel, Peter; Zhang, Lingjiao; Kim, Chung Kwon; Borovjagin, Anton; Dey, Mahua; Han, Yu; Baryshnikov, Anatoly Y; Lesniak, Maciej S

    2013-01-01

    Abstract Metalloproteinases are membrane-bound proteins that play a role in the cellular responses to antiglioma therapy. Previously, it has been shown that treatment of glioma cells with temozolomide (TMZ) and radiation (XRT) induces the expression of metalloproteinase 14 (MMP14). To investigate the role of MMP14 in gliomagenesis, we used several chemical inhibitors which affect MMP14 expression. Of all the inhibitors tested, we found that Marimastat not only inhibits the expression of MMP14 in U87 and U251 glioma cells, but also induces cell cycle arrest. To determine the relationship between MMP14 inhibition and alteration of the cell cycle, we used an RNAi technique. Genetic knockdown of MMP14 in U87 and U251 glioma cells induced G2/M arrest and decreased proliferation. Mechanistically, we show that TMZ and XRT regulated expression of MMP14 in clinical samples and in vitro models through downregulation of microRNA374. In vivo genetic knockdown of MMP14 significantly decreased tu