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  1. Targeting the erythropoietin receptor on glioma cells reduces tumour growth

    SciTech Connect

    Peres, Elodie A.; Valable, Samuel; Guillamo, Jean-Sebastien; Marteau, Lena; Bernaudin, Jean-Francois; Roussel, Simon; Lechapt-Zalcman, Emmanuele; Bernaudin, Myriam; Petit, Edwige

    2011-10-01

    Hypoxia has been shown to be one of the major events involved in EPO expression. Accordingly, EPO might be expressed by cerebral neoplastic cells, especially in glioblastoma, known to be highly hypoxic tumours. The expression of EPOR has been described in glioma cells. However, data from the literature remain descriptive and controversial. On the basis of an endogenous source of EPO in the brain, we have focused on a potential role of EPOR in brain tumour growth. In the present study, with complementary approaches to target EPO/EPOR signalling, we demonstrate the presence of a functional EPO/EPOR system on glioma cells leading to the activation of the ERK pathway. This EPO/EPOR system is involved in glioma cell proliferation in vitro. In vivo, we show that the down-regulation of EPOR expression on glioma cells reduces tumour growth and enhances animal survival. Our results support the hypothesis that EPOR signalling in tumour cells is involved in the control of glioma growth.

  2. Atorvastatin Promotes Cytotoxicity and Reduces Migration and Proliferation of Human A172 Glioma Cells.

    PubMed

    Oliveira, Karen A; Dal-Cim, Tharine; Lopes, Flávia G; Ludka, Fabiana K; Nedel, Cláudia B; Tasca, Carla I

    2017-02-08

    Malignant gliomas have resistance mechanisms to chemotherapy that enable tumor invasiveness and aggressiveness. Alternative therapies in cancer treatment, as statins, have been suggested to decrease proliferation, inhibit cell migration, and induce cell death. The aim of this study was to evaluate the effect of atorvastatin (ATOR) on cell viability, migration, proliferation, apoptosis, and autophagy in A172 human glioma cells. Temozolomide (TMZ), a chemotherapic used to glioma treatment, was tested as a comparison to cytotoxic effects on gliomas. Cell viability was also assessed in primary culture of cortical astrocytes. ATOR treatment (0.1 to 20 μM) did not alter astrocytic viability. However, in glioma cells, ATOR showed cytotoxic effect at 10 and 20 μM concentrations. TMZ (500 μM) reduced cell viability similarly to ATOR, and drug association did not show additive effect on cell viability. ATOR, TMZ, and their association decreased cell migration. ATOR also decreased glioma cell proliferation. ATOR increased apoptosis, and TMZ association showed a potentiation effect, enhancing it. ATOR and TMZ treatment increased acidic vesicular organelle (AVO) presence in A172 cells, an indicative of autophagy. ATOR effect of reducing A172 cell viability did not alter glutamate transport and glutamine synthetase activity, but it was partially prevented through antagonism of ionotropic and metabotropic glutamate receptors. Our data shows a cytotoxic effect of ATOR on glioma cells, whereas no toxicity was observed to astrocytes. ATOR showed similar cytotoxic effect as TMZ to glioma cells, and it may be a safer drug, regarding side effect induction, than chemotherapic agents.

  3. MiR-181b suppresses proliferation of and reduces chemoresistance to temozolomide in U87 glioma stem cells.

    PubMed

    Li, Ping; Lu, Xiaoming; Wang, Yingyi; Sun, Lihua; Qian, Chunfa; Yan, Wei; Liu, Ning; You, Yongping; Fu, Zhen

    2010-11-01

    MicroRNAs regulate self renewal and differentiation of cancer stem cells. There, we sought to identify the expression of miR-181b in glioma stem cells and investigate the biological effect of miR-181b on glioma stem cells in this study. MiR-181b expression was measured by real-time PCR in glioma stem cells isolated from U87 cells by FACS sorting. After miR-181b was overexpressed in U87 glioma stem cells by miR-181b lentiviral expression vector and/or treatment of temozolomide, secondary neurosphere assay, soft agar colony assay and MTT assay were performed. Compared with U87 cells, the expression of miR-181b was significantly decreased in U87 glioma stem cells. Overexpression of miR-181b decreased neurosphere formation by U87 glioma stem cells in vitro and suppressed colony formation in soft agar, and the cell growth inhibition rates increased in a time-dependent manner in U87 glioma stem cells infected with miR-181b lentivirus. Furthermore, miR-181b had a synergistic effect on temozolomide-induced inhibition of secondary neurosphere and soft agar colony, and on cell growth inhibition rates. MiR-181b functions as a tumor suppressor that suppresses proliferation and reduces chemoresistance to temozolomide in glioma stem cells.

  4. Expression of murine interleukin 7 in a murine glioma cell line results in reduced tumorigenicity in vivo.

    PubMed Central

    Aoki, T; Tashiro, K; Miyatake, S; Kinashi, T; Nakano, T; Oda, Y; Kikuchi, H; Honjo, T

    1992-01-01

    We have examined the immunoregulatory effect of local and continuous secretion of interleukin 7 (IL-7) from murine glioma cells (203-glioma) engineered by murine IL-7 gene transfection. Secretion of IL-7 from glioma cells did not result in morphology or growth rate changes but did reduce tumorigenicity in vivo in proportion to the amount of IL-7 produced. This reduction in tumorigenicity could be reversed in a dose-dependent fashion by injection of anti-IL-7 neutralizing monoclonal antibody at the tumor site. Mice immunized with IL-7-producing glioma cells showed a specific immune response to 203-glioma but not to two other syngeneic cell lines (B-16, a melanoma, and YM-12, a fibrosarcoma). IL-7-producing glioma cells were not rejected in mice depleted of CD8+ cells but were rejected in mice depleted of CD4+ or NK1.1+ cells. These results suggest that CD8+ T cells may play an important role in tumor rejection. Images PMID:1570303

  5. Sea Buckthorn Leaf Extract Inhibits Glioma Cell Growth by Reducing Reactive Oxygen Species and Promoting Apoptosis.

    PubMed

    Kim, Sung-Jo; Hwang, Eunmi; Yi, Sun Shin; Song, Ki Duk; Lee, Hak-Kyo; Heo, Tae-Hwe; Park, Sang-Kyu; Jung, Yun Joo; Jun, Hyun Sik

    2017-02-08

    Hippophae rhamnoides L., also known as sea buckthorn (SBT), possesses a wide range of biological and pharmacological activities. However, the underlying mechanism is largely unknown. The present study examined whether SBT leaf extract could inhibit proliferation and promote apoptosis of rat glioma C6 cells. The results revealed that the treatment with SBT leaf extract inhibited proliferation of rat C6 glioma cells in a dose-dependent manner. SBT-induced reduction of C6 glioma cell proliferation and viability was accompanied by a decrease in production of reactive oxygen species (ROS), which are critical for the proliferation of tumor cells. SBT treatment not only significantly upregulated the expression of the pro-apoptotic protein Bcl-2-associated X (Bax) but also promoted its localization in the nucleus. Although increased expression and nuclear translocation of Bax were observed in SBT-treated C6 glioma cells, the induced nuclear morphological change was distinct from that of typical apoptotic cells in that most of SBT-treated cells were characterized by convoluted nuclei with cavitations and clumps of chromatin. All of these results suggest that SBT leaf extract could inhibit the rapid proliferation of rat C6 glioma cells, possibly by inducing the early events of apoptosis. Thus, SBT may serve as a potential therapeutic candidate for the treatment of glioma.

  6. Nrdp1-mediated ErbB3 degradation inhibits glioma cell migration and invasion by reducing cytoplasmic localization of p27(Kip1).

    PubMed

    Shi, Hengliang; Gong, Hui; Cao, Kuan; Zou, Shenshan; Zhu, Bingxin; Bao, Hanmo; Wu, Yuxuan; Gao, Yong; Tang, Yuan; Yu, Rutong

    2015-09-01

    We previously reported that loss of Nrdp1 contributes to human glioma progression by reducing apoptosis. However, the role of Nrdp1 in glioma migration and invasion has not been investigated. Here, we report that ErbB3, a substrate of Nrdp1, is undetectable in normal brain tissues and grade II/III glioma tissues, but is abundant in a certain percentage of grade IV glioma tissues and is associated with the loss of Nrdp1. This suggests that Nrdp1 may be involved in glioma migration and invasion by regulating ErbB3. Thus, the role of Nrdp1/ErbB3 signaling in glioma cell migration and invasion was investigated using Nrdp1 loss- and gain-of-function. The results show that down-regulation of Nrdp1 by use of short hairpin RNA promoted glioma cell migration and invasion. In contrast, overexpression of Nrdp1 significantly inhibited glioma cell migration and invasion. Further investigation on molecular targets revealed that Nrdp1 decreased the level of ErbB3, which resulted in decreasing p-AKT thereby reducing cytoplasmic p27(Kip1). Taken together, these findings suggest that Nrdp1-mediated ErbB3 degradation suppresses glioma migration and invasion and that loss of Nrdp1 may amplify ErbB3 signaling to contribute to glioma migration and invasion. These findings suggest that Nrdp1 may be a target for glioma therapy.

  7. Therapeutic concentration of morphine reduces oxidative stress in glioma cell line

    PubMed Central

    Almeida, M.B.; Costa-Malaquias, A.; Nascimento, J.L.M.; Oliveira, K.R.; Herculano, A.M.; Crespo-López, M.E.

    2014-01-01

    Morphine is a potent analgesic opioid used extensively for pain treatment. During the last decade, global consumption grew more than 4-fold. However, molecular mechanisms elicited by morphine are not totally understood. Thus, a growing literature indicates that there are additional actions to the analgesic effect. Previous studies about morphine and oxidative stress are controversial and used concentrations outside the range of clinical practice. Therefore, in this study, we hypothesized that a therapeutic concentration of morphine (1 μM) would show a protective effect in a traditional model of oxidative stress. We exposed the C6 glioma cell line to hydrogen peroxide (H2O2) and/or morphine for 24 h and evaluated cell viability, lipid peroxidation, and levels of sulfhydryl groups (an indicator of the redox state of the cell). Morphine did not prevent the decrease in cell viability provoked by H2O2 but partially prevented lipid peroxidation caused by 0.0025% H2O2 (a concentration allowing more than 90% cell viability). Interestingly, this opioid did not alter the increased levels of sulfhydryl groups produced by exposure to 0.0025% H2O2, opening the possibility that alternative molecular mechanisms (a direct scavenging activity or the inhibition of NAPDH oxidase) may explain the protective effect registered in the lipid peroxidation assay. Our results demonstrate, for the first time, that morphine in usual analgesic doses may contribute to minimizing oxidative stress in cells of glial origin. This study supports the importance of employing concentrations similar to those used in clinical practice for a better approximation between experimental models and the clinical setting. PMID:24728211

  8. Glioma

    MedlinePlus

    ... cells are called mixed gliomas. Tumors such as “optic nerve glioma” and “brain stem glioma” are named ... Oligodendroglioma: Click here to learn more about oligodendroglioma. Optic Glioma: These tumors may involve any part of ...

  9. Estradiol reduces nonclassical transcription at cyclic adenosine 3',5'-monophosphate response elements in glioma cells expressing estrogen receptor alpha.

    PubMed

    Mhyre, Andrew J; Shapiro, Robert A; Dorsa, Daniel M

    2006-04-01

    Estradiol can protect the brain from a variety of insults by activating membrane-initiated signaling pathways, and thereby modulate gene expression and lead to functional changes in neurons. These direct neuronal effects of the hormone have been well documented; however, it is less understood what effects estradiol may have on nonneuronal cells of the central nervous system. There is evidence that estradiol levels can induce the release of glial-derived growth factors and other cytokines, suggesting that estradiol may both directly and indirectly protect neurons. To determine whether 17beta-estradiol (E2) can activate rapid signaling and modulate nonclassical transcription in astrocytes, we stably transfected the C6 rat glioblastoma cell line with human estrogen receptor (ER) alpha (C6ERalpha) or rat ERbeta (C6ERbeta). Introduction of a cAMP response element-luciferase reporter gene into C6, C6ERalpha, and C6ERbeta cells leads to the observation that E2 treatment reduced isoproterenol-stimulated luciferase activity by 35% in C6ERalpha but had no effect on reporter gene expression in C6ERbeta or untransfected C6 cells. A similar effect was seen with a membrane-impermeable estrogen (E2-BSA), suggesting the modulation of nonclassical transcription by estradiol treatment is mediated by the activation of a membrane-initiated signaling pathway. Furthermore, pretreatment with wortmannin (phosphatidylinsositol 3-kinase) or U73122 (phospholipase C) attenuated the E2-induced reduction in nonclassical transcription. We conclude that E2 treatment reduces cAMP response element-mediated transcription in glioma cells expressing ERalpha and that this reduction is dependent on the activation of membrane-initiated signaling. These findings suggest a novel model of estrogen rapid signaling in astrocytes that leads to modulation of nonclassical transcription.

  10. P02.04MICRORNA-MEDIATED DOWN-REGULATION OF NKG2D LIGAND EXPRESSION REDUCES GLIOMA CELL IMMUNOGENICITY

    PubMed Central

    Codo, P.; Weller, M.; Meister, G.; Szabo, E.; Steinle, A.; Wolter, M.; Reifenberger, G.; Roth, P.

    2014-01-01

    Glioblastoma is a primary brain tumor with a dismal prognosis despite comprehensive therapeutic regimens. It is characterized by diffuse infiltration of the surrounding healthy brain tissue, well-adapted to hypoxic conditions and regarded as paradigmatic for tumor-associated immunosuppression. One of the major activating receptors of natural killer (NK) cells is NKG2D. It binds to at least 8 ligands (NKG2DL) which are induced after malignant transformation and cellular stress. Regulation of NKG2DL expression may be affected by endogenous RNA molecules known as microRNA (miRNA). Here, we aimed at characterizing the role of miRNA in the control of NKG2DL expression in glioma cells. We selected 6 miRNA that were described or predicted to target NKG2DL. Three of the miRNA candidates, miR-20a, miR-93 and miR-106b, were expressed in glioma cell lines and were also detected in glioblastoma tissue specimens. Silencing of these miRNA with locked nucleic acid (LNA) molecules resulted in an up-regulation of NKG2DL cell surface levels which translated into increased sensitivity to immune cell killing. This effect was reversed by neutralizing NKG2D antibodies, confirming that enhanced immune cell lysis upon miRNA silencing was mediated through the NKG2D system. We conclude that the expression of several miRNA may contribute to the immune escape of glioma cells at the level of the NKG2D system. Therapeutic targeting of miRNA that regulate NKG2DL levels may therefore represent a promising approach to allow for more potent immune responses against glioblastoma.

  11. Extract from mistletoe, Viscum album L., reduces Hsp27 and 14-3-3 protein expression and induces apoptosis in C6 rat glioma cells.

    PubMed

    Uçar, E Ö; Arda, N; Aitken, A

    2012-08-24

    Extracts of mistletoe (Viscum album) are intensively used in complementary medicine, but their mechanisms are not fully understood in most cases, and the effects on metabolism have not been investigated in detail. However, some biologically active natural products are well known to provoke unexpected cellular responses. They reduce overexpression of heat shock proteins (Hsps) in cancer cells. The aim of the current study was to determine whether methanolic extract of V. album, which possesses antioxidant activity, has an effect on expression levels of Hsp27 and 14-3-3 proteins in a C6 glioma cell line. For the first time, the apoptosis-inducing effect of this extract was also determined via caspase-3 activation in the cells. Overexpression of Hsps was induced by heat shock at 42°C for 1 h. Expression levels of Hsp27 and 14-3-3 proteins were determined using Western blot analysis. The apoptosis-inducing effect was also evaluated via caspase-3 activation in C6 glioma cells. Pretreatment of the cells with a nontoxic dose (100 μg/mL) of V. album extract before heat shock significantly reduced expression levels of Hsp27 (73%) and 14-3-3β (124%), 14-3-3γ (23%), and 14-3-3ζ (84%) proteins. Pretreatment with the extract before heat shock increased apoptosis via caspase-3 activation (60%) in C6 glioma cells. This result suggested that the methanolic extract of V. album downregulates expression of Hsp27 and 14-3-3 chaperone proteins and induces apoptosis, which warrants further exploration as a potential bioactive compound for cancer therapy.

  12. Myeloid-derived suppressor cells in gliomas

    PubMed Central

    Kaminska, Bozena

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of early myeloid progenitors and precursors at different stages of differentiation into granulocytes, macrophages, and dendritic cells. Blockade of their differentiation into mature myeloid cells in cancer results in an expansion of this population. High-grade gliomas are the most common malignant tumours of the central nervous system (CNS), with a poor prognosis despite intensive radiation and chemotherapy. Histopathological and flow cytometry analyses of human and rodent experimental gliomas revealed the extensive heterogeneity of immune cells infiltrating gliomas and their microenvironment. Immune cell infiltrates consist of: resident (microglia) and peripheral macrophages, granulocytes, myeloid-derived suppressor cells, and T lymphocytes. Intratumoural density of glioma-associated MDSCs correlates positively with the histological grade of gliomas and patient’s survival. MDSCs have the ability to attract T regulatory lymphocytes to the tumour, but block the activation of tumour-reactive CD4+ T helper cells and cytotoxic CD8+ T cells. Immunomodulatory mechanisms employed by malignant gliomas pose an appalling challenge to brain tumour immunotherapy. In this mini-review we describe phenotypic and functional characteristics of MDSCs in humans and rodents, and their occurrence and potential roles in glioma progression. While understanding the complexity of immune cell interactions in the glioma microenvironment is far from being accomplished, there is significant progress that may lead to the development of immunotherapy for gliomas. PMID:28373814

  13. Multiwalled carbon nanotubes inhibit fluorescein extrusion and reduce plasma membrane potential in in vitro human glioma cells.

    PubMed

    Xu, Yonghong; Chen, Xiao; Cheng, Yuli; Xing, Yiqiao

    2010-06-01

    In the study on the interactions of carbon nanotubes with living cells, the cell membrane deserves particular attention as it provides the first interface to initiate CNTs-cell interactions. In the present study, the inhibiting effect of multiwalled carbon nanotubes on the extrusion of fluorescein in human glioma cells was demonstrated using two procedures. To provide clues to explanation of this effect, intracellular glutathione content and reactive oxygen species production were determined as fluorescein is a specific substrate of cell membrane multidrug resistance-related protein whose transport activity requires glutathione which can be depleted under oxidative stress. The plasma membrane potential was also probed as the susceptibility of fluorescein efflux to modulation of the plasma membrane potential has been documented. Results showed a remarkable decrease in cellular glutathione level as well as an increase in reactive oxygen species production. Probe staining also indicated decreased plasma membrane potential. The data suggested that multiwalled carbon nanotubes may affect the transport activity of cell membrane multidrug resistance-related protein through reduction of intracellular glutathione content. Hypopolarization of the plasma membrane may also contribute to MWCNTs' effect. Implications of these findings are discussed.

  14. Transfection with liver-type glutaminase cDNA alters gene expression and reduces survival, migration and proliferation of T98G glioma cells.

    PubMed

    Szeliga, Monika; Obara-Michlewska, Marta; Matyja, Ewa; Łazarczyk, Marzena; Lobo, Carolina; Hilgier, Wojciech; Alonso, Francisco J; Márquez, Javier; Albrecht, Jan

    2009-07-01

    Liver-type glutaminase (LGA) is a glutaminase isoform that has been implicated in transcription modulation. LGA mRNA is absent from postoperative samples of primary gliomas and is low in cultured astrocytes. In this study, stable transfection of T98G cells with a vector carrying human LGA sequence increased the expression of LGA mRNA and protein, and the ability of the cells to degrade glutamine (Gln), as manifested by a three-fold reduction of their steady-state Gln content and a 2.5-fold increase of their glutamate (Glu) content. The transfected cells (TLGA cells) showed a 40% decrease of cell survival as assessed by colony formation, well correlated with significant reduction of mitochondrial activity as demonstrated with MTT test. Also, a 45% reduction of cell migration and a 47% decrease of proliferation index (Ki67 immunostaining) were found as compared with sham-transfected cells. Microarray analysis, which included over 47,000 transcripts, revealed a significantly altered expression of 85 genes in TLGA, but not in sham-transfected or control cells (P < 0.005). Microarray data were confirmed with real-time PCR analysis for eight genes potentially relevant to malignancy: S100A16, CAPN2, FNDC3B, DYNC1LI1, TIMP4, MGMT, ADM, and TIMP1. Of these changes, decreased expression of S100A16 and MGMT can be best reconciled with the current views on the role of their protein products in glioma malignancy. Malignancy-reducing effect of newly inserted LGA mRNA in glioblastoma cells can be reconciled with a hypothesis that absence of such a modulatory mechanism in glia-derived tumors deprived of LGA mRNA may facilitate some aspects of their progression.

  15. Salinomycin inhibits the tumor growth of glioma stem cells by selectively suppressing glioma-initiating cells.

    PubMed

    Chen, Tunan; Yi, Liang; Li, Fei; Hu, Rong; Hu, Shengli; Yin, Yi; Lan, Chuan; Li, Zhao; Fu, Chuhua; Cao, Liu; Chen, Zhi; Xian, Jishu; Feng, Hua

    2015-04-01

    Glioma‑initiating cells are a small population of cells that have the ability to undergo self‑renewal and initiate tumorigenesis. In the present study, the potential role of salinomycin, a polyether antibiotic, on the suppression of glioma cell growth was investigated. GL261 glioma cells were maintained in a stem‑cell‑like status [GL261 neurospheres (GL261‑NS)] or induced for differentiation [GL261 adherent cells (GL261‑AC)]. It was demonstrated that salinomycin significantly reduced the cell viability of GL261‑NS and GL261‑AC cells in a dose‑dependent manner, with a more substantial inhibition of GL261‑NS proliferation (P<0.05). The inhibitory effect of salinomycin on cell growth was more effective than that of 1‑(4‑amino‑2‑methyl‑5‑pyrimid l)‑methyl‑3‑(2‑chloroethyl)‑3‑nitrosourea hydrochloride and vincristine (P<0.05). Salinomycin depleted GL261‑NS from tumorspheres and induced cell apoptosis. In addition, salinomycin prolonged the median survival time of glioma‑bearing mice (P<0.05). Therefore, the present study indicated that salinomycin may preferentially inhibit glioma‑initiated cell growth by inducing apoptosis, suggesting that salinomycin may provide a valuable therapeutic strategy for the treatment of malignant glioma.

  16. NDRG1 overexpressing gliomas are characterized by reduced tumor vascularization and resistance to antiangiogenic treatment.

    PubMed

    Broggini, Thomas; Wüstner, Marie; Harms, Christoph; Stange, Lena; Blaes, Jonas; Thomé, Carina; Harms, Ulrike; Mueller, Susanne; Weiler, Markus; Wick, Wolfgang; Vajkoczy, Peter; Czabanka, Marcus

    2016-10-01

    Hypoxia-regulated molecules play an important role in vascular resistance to antiangiogenic treatment. N-myc downstream-regulated-gene 1 (NDRG1) is significantly upregulated during hypoxia in glioma. It was the aim of the present study to analyze the role of NDRG1 on glioma angiogenesis and on antiangiogenic treatment. Orthotopically implanted NDRG1 glioma showed reduced tumor growth and vessel density compared to controls. RT-PCR gene array analysis revealed a 30-fold TNFSF15 increase in NDRG1 tumors. Consequently, the supernatant from NDRG1 transfected U87MG glioma cells resulted in reduced HUVEC proliferation, migration and angiogenic response in tube formation assays in vitro. This effect was provoked by increased TNFSF15 promoter activity in NDRG1 cells. Mutations in NF-κB and AP-1 promoter response elements suppressed TNFSF15 promoter activity. Moreover, U87MG glioma NDRG1 knockdown supernatant contained multiple proangiogenic proteins and increased HUVEC spheroid sprouting. Sunitinib treatment of orhotopically implanted mice reduced tumor volume and vessel density in controls; in NDRG1 overexpressing cells no reduction of tumor volume or vessel density was observed. NDRG1 overexpression leads to reduced tumor growth and angiogenesis in experimental glioma via upregulation of TNFSF15. In NDRG1 overexpressing glioma antiangiogenic treatment does not yield a therapeutic response.

  17. Expression of TIP-1 Confers Radioresistance of Malignant Glioma Cells

    PubMed Central

    Han, Miaojun; Wang, Hailun; Zhang, Hua-Tang; Han, Zhaozhong

    2012-01-01

    Background Malignant gliomas represent one group of tumors that poorly respond to ionizing radiation (IR) alone or combined with chemotherapeutic agents because of the intrinsic or acquired resistance. In this study, TIP-1 was identified as one novel protein that confers resistance of glioma cells to IR. Methodology/Principal Findings Meta-analysis indicated that high TIP-1 expression levels correlate with the poor prognosis of human malignant gliomas after radiotherapy. Studies with established human glioma cell lines demonstrated that TIP-1 depletion with specific shRNAs sensitized the cells to IR, whereas an ectopic expression of TIP-1 protected the glioma cells from the IR-induced DNA damage and cell death. Biochemical studies indicated that TIP-1 protein promoted p53 ubiquitination and resulted in a reduced p53 protein level. Furthermore, p53 and its ubiquitination are required for the TIP-1 regulated cellular response to IR. A yeast two-hybrid screening identified that TIP-1, through its single PDZ domain, binds to the carboxyl terminus of LZAP that has been studied as one tumor suppressor functioning through ARF binding and p53 activation. It was revealed that the presence of TIP-1 enhances the protein association between LZAP and ARF and modulates the functionality of ARF/HDM2 toward multi-ubiquitination of p53, while depleting TIP-1 rescued p53 from polyubiquitination and degradation in the irradiated glioma cells. Studies with a mouse xenograft model indicated that depleting TIP-1 within D54 cells improved the tumor growth control with IR. Conclusions/Significance This study provided the first evidence showing that TIP-1 modulates p53 protein stability and is involved in the radioresistance of malignant gliomas, suggesting that antagonizing TIP-1 might be one novel approach to sensitize malignant gliomas to radiotherapy. PMID:23028987

  18. Atorvastatin suppresses glioma invasion and migration by reducing microglial MT1-MMP expression.

    PubMed

    Yongjun, Yi; Shuyun, Huang; Lei, Chen; Xiangrong, Chen; Zhilin, Yang; Yiquan, Ke

    2013-07-15

    Microglia, the immune cells of the brain, often present in large numbers in gliomas, where they promote tumor growth and invasiveness. This study found that atorvastatin reduced the pro-tumorigenic effects of microglia on glioma migration and invasion by reducing the microglial expression of membrane type 1 metalloproteinase (MT1-MMP). The results suggest that down-regulation of MT1-MMP is controlled by a p38 MAPK pathway in microglia. Taken together, the results support further research on atorvastatin as a candidate for glioma therapy by targeting microglia.

  19. Lower expression of Nrdp1 in human glioma contributes tumor progression by reducing apoptosis.

    PubMed

    Shi, Hengliang; Du, Jin; Wang, Lei; Zheng, Bao; Gong, Hui; Wu, Yuxuan; Tang, Yuan; Gao, Yong; Yu, Rutong

    2014-10-01

    Ubiquitin ligase Nrdp1 (neuregulin receptor degradation protein 1) plays important roles in multiple physiological process because it can ubiquitinate various substrates such as ErbB3, BRUCE, MyD88, C/EBPβ, and Parkin, and so forth. In addition to the physiological function, it was also found to be involved in tumor progression. It has been shown that loss of Nrdp1 enhances breast cancer cell growth. Up to now, the role of Nrdp1 in glioma has not been elucidated. Here, we reported that Nrdp1 as well as cleaved caspase 3 was lower expressed in human glioma tissues comparing with the nontumorous. And then we found that the expression of Nrdp1 and cleaved caspase 3 was increased in the treatment of Temozolomide (TMZ), a drug for glioma chemotherapy. Further investigation indicated that transient transfection of Nrdp1 significantly promoted cell apoptosis by aggravating the degradation of BRUCE and activation of caspase 3. In addition, overexpression of Nrdp1 augmented TMZ induced apoptosis by evaluating the degradation of BRUCE and the activation of caspase 3, while silencing of Nrdp1 reduced the sensitivity to the TMZ by inhibiting the degradation of BRUCE and the activation of caspase 3 in human glioma cells. These observations show that Nrdp1 is a pro-apoptotic protein in human glioma and lower expression of Nrdp1 in human glioma may promote tumor progression by reducing apoptosis, suggesting that Nrdp1 may be an important regulator in the development of human glioma.

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

    PubMed

    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.

  1. Lymphoid Cell-Glioma Cell Interaction Enhances Cell Coat Production by Human Gliomas: Novel Suppressor Mechanism

    NASA Astrophysics Data System (ADS)

    Dick, Steven J.; Macchi, Beatrice; Papazoglou, Savvas; Oldfield, Edward H.; Kornblith, Paul L.; Smith, Barry H.; Gately, Maurice K.

    1983-05-01

    Certain human glioma lines produce mucopolysaccharide coats that impair the generation of cytolytic lymphocytes in response to these lines in vitro. Coat production is substantially enhanced by the interaction of glioma cells with a macromolecular factor released by human peripheral blood mononuclear cells in culture. This interaction thus constitutes an unusual mechanism by which inflammatory cells may nonspecifically suppress the cellular immune response to at least one class of solid tumors in humans.

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

    PubMed Central

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

    2017-01-01

    Background. 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. Methods. 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. Results. 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. Conclusions. 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. PMID:27365097

  3. Enriched environment reduces glioma growth through immune and non-immune mechanisms in mice

    PubMed Central

    Garofalo, Stefano; D’Alessandro, Giuseppina; Chece, Giuseppina; Brau, Frederic; Maggi, Laura; Rosa, Alessandro; Porzia, Alessandra; Mainiero, Fabrizio; Esposito, Vincenzo; Lauro, Clotilde; Benigni, Giorgia; Bernardini, Giovanni; Santoni, Angela; Limatola, Cristina

    2015-01-01

    Mice exposed to standard (SE) or enriched environment (EE) were transplanted with murine or human glioma cells and differences in tumour development were evaluated. We report that EE exposure affects: (i) tumour size, increasing mice survival; (ii) glioma establishment, proliferation and invasion; (iii) microglia/macrophage (M/Mφ) activation; (iv) natural killer (NK) cell infiltration and activation; and (v) cerebral levels of IL-15 and BDNF. Direct infusion of IL-15 or BDNF in the brain of mice transplanted with glioma significantly reduces tumour growth. We demonstrate that brain infusion of IL-15 increases the frequency of NK cell infiltrating the tumour and that NK cell depletion reduces the efficacy of EE and IL-15 on tumour size and of EE on mice survival. BDNF infusion reduces M/Mφ infiltration and CD68 immunoreactivity in tumour mass and reduces glioma migration inhibiting the small G protein RhoA through the truncated TrkB.T1 receptor. These results suggest alternative approaches for glioma treatment. PMID:25818172

  4. PinX1 inhibits cell proliferation, migration and invasion in glioma cells.

    PubMed

    Mei, Peng-Jin; Chen, Yan-Su; Du, Ying; Bai, Jin; Zheng, Jun-Nian

    2015-03-01

    PinX1 induces apoptosis and suppresses cell proliferation in some cancer cells, and the expression of PinX1 is frequently decreased in some cancer and negatively associated with metastasis and prognosis. However, the precise roles of PinX1 in gliomas have not been studied. In this study, we found that PinX1 obviously reduced the gliomas cell proliferation through regulating the expressions of cell cycle-relative molecules to arrest cell at G1 phase and down-regulating the expression of component telomerase reverse transcriptase (hTERT in human), which is the hardcore of telomerase. Moreover, PinX1 could suppress the abilities of gliomas cell wound healing, migration and invasion via suppressing MMP-2 expression and increasing TIMP-2 expression. In conclusion, our results suggested that PinX1 may be a potential suppressive gene in the progression of gliomas.

  5. Stimulation of glioma cell motility by expression, proteolysis, and release of the L1 neural cell recognition molecule

    PubMed Central

    Yang, Muhua; Adla, Shalini; Temburni, Murali K; Patel, Vivek P; Lagow, Errin L; Brady, Owen A; Tian, Jing; Boulos, Magdy I; Galileo, Deni S

    2009-01-01

    Background Malignant glioma cells are particularly motile and can travel diffusely through the brain parenchyma, apparently without following anatomical structures to guide their migration. The neural adhesion/recognition protein L1 (L1CAM; CD171) has been implicated in contributing to stimulation of motility and metastasis of several non-neural cancer types. We explored the expression and function of L1 protein as a stimulator of glioma cell motility using human high-grade glioma surgical specimens and established rat and human glioma cell lines. Results L1 protein expression was found in 17 out of 18 human high-grade glioma surgical specimens by western blotting. L1 mRNA was found to be present in human U-87/LacZ and rat C6 and 9L glioma cell lines. The glioma cell lines were negative for surface full length L1 by flow cytometry and high resolution immunocytochemistry of live cells. However, fixed and permeablized cells exhibited positive staining as numerous intracellular puncta. Western blots of cell line extracts revealed L1 proteolysis into a large soluble ectodomain (~180 kDa) and a smaller transmembrane proteolytic fragment (~32 kDa). Exosomal vesicles released by the glioma cell lines were purified and contained both full-length L1 and the proteolyzed transmembrane fragment. Glioma cell lines expressed L1-binding αvβ5 integrin cell surface receptors. Quantitative time-lapse analyses showed that motility was reduced significantly in glioma cell lines by 1) infection with an antisense-L1 retroviral vector and 2) L1 ectodomain-binding antibodies. Conclusion Our novel results support a model of autocrine/paracrine stimulation of cell motility in glioma cells by a cleaved L1 ectodomain and/or released exosomal vesicles containing L1. This mechanism could explain the diffuse migratory behavior of high-grade glioma cancer cells within the brain. PMID:19874583

  6. Eckol suppresses maintenance of stemness and malignancies in glioma stem-like cells

    SciTech Connect

    Hyun, Kyung-Hwan; Yoon, Chang-Hwan; Kim, Rae-Kwon; Lim, Eun-Jung; An, Sungkwan; Park, Myung-Jin; Hyun, Jin-Won; Suh, Yongjoon; Kim, Min-Jung; Lee, Su-Jae

    2011-07-01

    A subpopulation of cancer cells with stem cell properties is responsible for tumor maintenance and progression, and may contribute to resistance to anticancer treatments. Thus, compounds that target cancer stem-like cells could be usefully applied to destroy cancer. In this study, we investigated the effect of Eckol, a phlorotannin compound, on stemness and malignancies in glioma stem-like cells. To determine whether Eckol targets glioma stem-like cells, we examined whether Eckol treatment could change the expression levels of glioma stem-like cell markers and self-renewal-related proteins as well as the sphere forming ability, and the sensitivity to anticancer treatments. Alterations in the malignant properties of sphere-derived cells by Eckol were also investigated by soft-agar colony forming assay, by xenograft assay in nude mice, and by cell invasion assay. Treatment of sphere-forming glioma cells with Eckol effectively decreased the sphere formation as well as the CD133{sup +} cell population. Eckol treatment suppressed expression of the glioma stem-like cell markers and the self-renewal-related proteins without cell death. Moreover, treatment of glioma stem-like cells with Eckol significantly attenuated anchorage-independent growth on soft agar and tumor formation in xenograft mice. Importantly, Eckol treatment effectively reduced the resistance of glioma stem-like cells to ionizing radiation and temozolomide. Treatment of glioma stem-like cells with Eckol markedly blocked both phosphoinositide 3-kinase-Akt and Ras-Raf-1-Erk signaling pathways. These results indicate that the natural phlorotannin Eckol suppresses stemness and malignancies in glioma stem-like cells, and thereby makes glioma stem-like cells more sensitive to anticancer treatments, providing novel therapeutic strategies targeting specifically cancer stem-like cells.

  7. Autophagy contributes to gefitinib-induced glioma cell growth inhibition

    SciTech Connect

    Chang, Cheng-Yi; Kuan, Yu-Hsiang; Ou, Yen-Chuan; Li, Jian-Ri; Wu, Chih-Cheng; Pan, Pin-Ho; Chen, Wen-Ying; Huang, Hsuan-Yi; Chen, Chun-Jung

    2014-09-10

    Epidermal growth factor receptor tyrosine kinase inhibitors, including gefitinib, have been evaluated in patients with malignant gliomas. However, the molecular mechanisms involved in gefitinib-mediated anticancer effects against glioma are incompletely understood. In the present study, the cytostatic potential of gefitinib was demonstrated by the inhibition of glioma cell growth, long-term clonogenic survival, and xenograft tumor growth. The cytostatic consequences were accompanied by autophagy, as evidenced by monodansylcadaverine staining of acidic vesicle formation, conversion of microtubule-associated protein-1 light chain 3-II (LC3-II), degradation of p62, punctate pattern of GFP-LC3, and conversion of GFP-LC3 to cleaved-GFP. Autophagy inhibitor 3-methyladenosine and chloroquine and genetic silencing of LC3 or Beclin 1 attenuated gefitinib-induced growth inhibition. Gefitinib-induced autophagy was not accompanied by the disruption of the Akt/mammalian target of rapamycin signaling. Instead, the activation of liver kinase-B1/AMP-activated protein kinase (AMPK) signaling correlated well with the induction of autophagy and growth inhibition caused by gefitinib. Silencing of AMPK suppressed gefitinib-induced autophagy and growth inhibition. The crucial role of AMPK activation in inducing glioma autophagy and growth inhibition was further supported by the actions of AMP mimetic AICAR. Gefitinib was shown to be capable of reducing the proliferation of glioma cells, presumably by autophagic mechanisms involving AMPK activation. - Highlights: • Gefitinib causes cytotoxic and cytostatic effect on glioma. • Gefitinib induces autophagy. • Gefitinib causes cytostatic effect through autophagy. • Gefitinib induces autophagy involving AMPK.

  8. Decreased Expression of MiRNA-204-5p Contributes to Glioma Progression and Promotes Glioma Cell Growth, Migration and Invasion

    PubMed Central

    Xia, Zhiqiang; Liu, Fang; Zhang, Jian; Liu, Li

    2015-01-01

    Gliomas are the most common malignant primary brain tumors in adults and exhibit a spectrum of aberrantly aggressive phenotype. Although increasing evidence indicated that the deregulation of microRNAs (miRNAs) contributes to tumorigenesis and invasion, little is known about the roles of miR-204-5p in human gliomas. In the present study, the expression of miR-204-5p in clinical glioma tissues was measured by qRT-PCR. The effects of miR-204-5p on glioma cell growth and metastasis were examined by overexpressing or inhibiting miR-204-5p. We found that the expression level of miR-204-5p was significantly reduced in clinical glioma tissues compared with normal brain tissues. Moreover, we revealed that the introduction of miR-204-5p dramatically suppressed glioma cell growth, migration and invasion. Furthermore, mechanistic investigations revealed that RAB22A, a member of the RAS oncogene family, is a direct functional target of miR-204-5p in gliomas. In vivo, restoring miR-204-5p expression in glioma cells suppressed tumorigenesis and increased overall host survival. Our findings suggest that miR-204-5p is a cancer suppressor miRNA and overexpression of miR-204-5p is a novel glioma treatment strategy. PMID:26134825

  9. Reduced glioma growth following dexamethasone or anti-angiopoietin 2 treatment.

    PubMed

    Villeneuve, Jérôme; Galarneau, Hugo; Beaudet, Marie-Josée; Tremblay, Pierrot; Chernomoretz, Ariel; Vallières, Luc

    2008-07-01

    All patients with glioblastoma, the most aggressive and common form of brain cancer, develop cerebral edema. This complication is routinely treated with dexamethasone, a steroidal anti-inflammatory drug whose effects on brain tumors are not fully understood. Here we show that dexamethasone can reduce glioma growth in mice, even though it depletes infiltrating T cells with potential antitumor activity. More precisely, T cells with helper or cytotoxic function were sensitive to dexamethasone, but not those that were negative for the CD4 and CD8 molecules, including gammadelta and natural killer (NK) T cells. The antineoplastic effect of dexamethasone was indirect, as it did not meaningfully affect the growth and gene expression profile of glioma cells in vitro. In contrast, hundreds of dexamethasone-modulated genes, notably angiopoietin 2 (Angpt2), were identified in cultured cerebral endothelial cells by microarray analysis. The ability of dexamethasone to attenuate Angpt2 expression was confirmed in vitro and in vivo. Selective neutralization of Angpt2 using a peptide-Fc fusion protein reduced glioma growth and vascular enlargement to a greater extent than dexamethasone, without affecting T cell infiltration. In conclusion, this study suggests a mechanism by which dexamethasone can slow glioma growth, providing a new therapeutic target for malignant brain tumors.

  10. Overexpression of SMC4 activates TGFβ/Smad signaling and promotes aggressive phenotype in glioma cells.

    PubMed

    Jiang, L; Zhou, J; Zhong, D; Zhou, Y; Zhang, W; Wu, W; Zhao, Z; Wang, W; Xu, W; He, L; Ma, Y; Hu, Y; Zhang, W; Li, J

    2017-03-13

    Overexpression of structural maintenance of chromosomes 4 (SMC4) has been reported to be involved in tumor cell growth, migration and invasion, and to be correlated with poor prognosis of cancer patient. However, its clinical significance and biological role in glioma remain unknown. Herein, we found that SMC4 expression at both mRNA and protein level was markedly increased in glioma cells and clinical tissues and that it correlated with poor prognosis. SMC4 overexpression markedly promoted the glioma cell proliferation rate and migration and invasive capability in vitro and in vivo, whereas SMC4 downregulation reduced it. Moreover, the transforming growth factor β (TGFβ)/Smad signaling pathway, which was activated in SMC4-transduced glioma cells and inhibited in SMC4-silenced glioma cells, contributed to SMC4-mediated glioma cell aggressiveness. Our results provide new insight into the oncofunction of SMC4 and the mechanism by which the TGFβ/Smad pathway is hyperactivated in gliomas, indicating that SMC4 is a valuable prognostic factor and a potential therapeutic target in gliomas.

  11. Multifunctional targeting vinorelbine plus tetrandrine liposomes for treating brain glioma along with eliminating glioma stem cells

    PubMed Central

    Li, Xue-tao; Tang, Wei; Jiang, Ying; Wang, Xiao-min; Wang, Yan-hong; Cheng, Lan; Meng, Xian-sheng

    2016-01-01

    Malignant brain glioma is the most lethal and aggressive type of cancer. Surgery and radiotherapy cannot eliminate all glioma stem cells (GSCs) and blood–brain barrier (BBB) restricts the movement of antitumor drugs from blood to brain, thus leading to the poor prognosis with high recurrence rate. In the present study, the targeting conjugates of cholesterol polyethylene glycol polyethylenimine (CHOL-PEG2000-PEI) and D-a-tocopheryl polyethylene glycol 1000 succinate vapreotide (TPGS1000-VAP) were newly synthesized for transporting drugs across the BBB and targeting glioma cells and GSCs. The multifunctional targeting vinorelbine plus tetrandrine liposomes were constructed by modifying the targeting conjugates. The studies were undertaken on BBB model, glioma cells, GSCs, and glioma-bearing mice. In vitro results showed that multifunctional targeting drugs-loaded liposomes with suitable physicochemical property could enhance the transport drugs across the BBB, increase the intracellular uptake, inhibit glioma cells and GSCs, penetrate and destruct the GSCs spheroids, and induce apoptosis via activating related apoptotic proteins. In vivo results demonstrated that multifunctional targeting drugs-loaded liposomes could significantly accumulate into brain tumor location, show the specificity to tumor sites, and result in a robust overall antitumor efficacy in glioma-bearing mice. These data suggested that the multifunctional targeting vinorelbine plus tetrandrine liposomes could offer a promising strategy for treating brain glioma. PMID:27029055

  12. Erythropoietin Augments Survival of Glioma Cells After Radiation and Temozolomide

    SciTech Connect

    Hassouna, Imam; Sperling, Swetlana; Kim, Ella; Schulz-Schaeffer, Walter; Rave-Fraenk, Margret; Hasselblatt, Martin; Jelkmann, Wolfgang; Giese, Alf; Ehrenreich, Hannelore

    2008-11-01

    Purpose: Despite beneficial effects of irradiation/chemotherapy on survival of glioblastoma (GBM) patients, collateral damage to intact neural tissue leads to 'radiochemobrain' and reduced quality of life in survivors. For prophylactic neuroprotection, erythropoietin (EPO) is a promising candidate, provided that concerns regarding potential tumor promoting effects are alleviated. Methods and Materials: Human GBM-derived cell lines U87, G44, G112, and the gliosarcoma-derived line G28 were treated with EPO, with and without combinations of irradiation or temozolomide (TMZ). Responsiveness of glioma cells to EPO was measured by cell migration from spheroids, cell proliferation, and clonogenic survival. Implantation of U87 cells into brains of nude mice, followed 5 days later by EPO treatment (5,000 U/kg intraperitoneal every other day for 2 weeks) should reveal effects of EPO on tumor growth in vivo. Reverse transcriptase-polymerase chain reaction was performed for EPOR, HIF-1{alpha}, and epidermal growth factor receptor (EGFR)vIII in cell lines and 22 human GBM specimens. Results: EPO did not modulate basal glioma cell migration and stimulated proliferation in only one of four cell lines. Importantly, EPO did not enhance tumor growth in mouse brains. Preincubation of glioma cells with EPO for 3 h, followed by irradiation and TMZ for another 24 h, resulted in protection against chemoradiation-induced cytotoxicity in three cell lines. Conversely, EPO induced a dose-dependent decrease in survival of G28 gliosarcoma cells. In GBM specimens, expression of HIF-1{alpha} correlated positively with expression of EPOR and EGFRvIII. EPOR and EGFRvIII expression did not correlate. Conclusions: EPO is unlikely to appreciably influence basal glioma growth. However, concomitant use of EPO with irradiation/chemotherapy in GBM patients is not advisable.

  13. F8-SIP mediated targeted photodynamic therapy leads to microvascular dysfunction and reduced glioma growth.

    PubMed

    Acker, G; Palumbo, A; Neri, D; Vajkoczy, P; Czabanka, M

    2016-08-01

    The extra domain A (ED A) of fibronectin has been identified as a tumor vessel specific neovascular marker in glioma. Antibody based vascular targeting against ED A of fibronectin allows precise accumulation of photosensitizer in glioma microvasculature and thereby promises to overcome drawbacks of current photodynamic therapy (PDT) for glioma treatment. Our aim was to characterize microcirculatory consequences of F8-small immunoprotein (SIP) mediated PDT by intravital microscopy (IVM) and to analyze the effects on glioma growth. For IVM SF126 glioma cells were implanted into dorsal skinfold-chamber of nude mice. PDT was performed after intravenous injection of photosensitizer (PS)-coupled F8-SIP or PBS (n = 4). IVM was performed before and after PDT for 4 days. Analysis included total and functional (TVD, FVD) vessel densities, perfusion index (PI), microvascular permeability and blood flow rate (Q). To assess tumor growth SF126 glioma cells were implanted subcutaneously. PDT was performed as a single and repetitive treatment after PS-F8-SIP injection (n = 5). Subcutaneous tumors were treated after uncoupled F8-SIP injection as control group (n = 5). PDT induced microvascular stasis and thrombosis with reduced FVD (24 h: 115.98 ± 0.7 vs. 200.8 ± 61.9 cm/cm(2)) and PI (39 ± 11 vs. 70 ± 10 %), whereas TVD was not altered (298 ± 39.2 vs. 278.2 ± 51 cm/cm(2)). Microvascular dysfunction recovered 4 days after treatment. Microvascular dysfunction led to a temporary reduction of glioma growth in the first 48 h after treatment with complete recovery 5 days after treatment. Repetitive PDT resulted in sustained reduction of tumor growth. F8-SIP mediated PDT leads to microvascular dysfunction and reduced glioma growth in a preclinical glioma model with recovery of microcirculation 4 days after treatment. Repetitive application of PDT overcomes microvascular recovery and leads to prolonged antiglioma effects.

  14. Adoptive cell transfer therapy for malignant gliomas.

    PubMed

    Ishikawa, Eiichi; Takano, Shingo; Ohno, Tadao; Tsuboi, Koji

    2012-01-01

    To date, various adoptive immunotherapies have been attempted for treatment of malignant gliomas using nonspecific and/or specific effector cells. Since the late 1980s, with the development of rIL-2, the efficacy of lymphokine-activated killer (LAK) cell therapy with or without rIL-2 for malignant gliomas had been tested with some modifications in therapeutic protocols. With advancements in technology, ex vivo expanded tumor specific cytotoxic T-lymphocytes (CTL) or those lineages were used in clinical trials with higher tumor response rates. In addition, combinations of those adoptive cell transfer using LAK cells, CTLs or natural killer (NK) cells with autologous tumor vaccine (ATV) therapy were attempted. Also, a strategy of high-dose (or lymphodepleting) chemotherapy followed by adoptive cell transfer has been drawing attentions recently. The most important role of these clinical studies using cell therapy was to prove that these ex vivo expanded effector cells could kill tumor cells in vivo. Although recent clinical results could demonstrate radiologic tumor shrinkage in a number of cases, cell transfer therapy alone has been utilized less frequently, because of the high cost of ex vivo cell expansion, the short duration of antitumor activity in vivo, and the recent shift of interest to vaccine immunotherapy. Nevertheless, NK cell therapy using specific feeder cells or allergenic NK cell lines have potentials to be a good choice of treatment because of easy ex vivo expansion and their efficacy especially when combined with vaccine therapy as they are complementary to each other. Also, further studies are expected to clarify the efficacy of the high-dose chemotherapy followed by a large scale cell transfer therapy as a new therapeutic strategy for malignant gliomas.

  15. Differential Glioma-Associated Tumor Antigen Expression Profiles of Human Glioma Cells Grown in Hypoxia

    PubMed Central

    Ge, Lisheng; Cornforth, Andrew N.; Hoa, Neil T.; Delgado, Christina; Chiou, Shiun Kwei; Zhou, Yi Hong; Jadus, Martin R.

    2012-01-01

    Human U251 and D54 glioma cells were tested for expression of 25 glioma-associated tumor antigen precursor proteins (TAPP) under hypoxic (1% O2) or normoxic (21% O2) conditions. Hypoxic glioma cell lines increased their mRNA expression for nine TAPP (Aim2, Art-4, EphA2, EZH2, Fosl1, PTH-rP, Sox 11, Whsc2 and YKL-40), as assessed by quantitative reverse transcriptase real-time/polymerase chain reaction (qRT-PCR). Increased differences with three hypoxic-induced TAPP: EZH2, Whsc2 and YKL-40 were shown at the protein levels by fluorescent antibody staining and quantitative electrophoretic analysis. Two TAPP (MRP3 and Trp1) were down-regulated by hypoxia in glioma cell lines. Growing the glioma cells under hypoxia for 13 days, followed by returning them back to normoxic conditions for 7 days, and restored the original normoxic TAPP profile. Thus, hypoxia was an environmental factor that stimulated the transient expression of these antigens. Intracranial xenografts grown in nude mice derived from U251 cells that had been cultured under neurosphere stem cell conditions showed increased expression of Whsc2 or YKL-40, demonstrating that these in vitro properties of glioma also occur in vivo. Whsc2-specific cytotoxic T lymphocytes killed the hypoxic U251 glioma cells better than normoxic glioma cells. The antigens expressed by hypoxic tumor cells may be a better source of starting tumor material for loading dendritic cells for novel immunotherapy of glioma using tumor-associated antigens. PMID:22957023

  16. Differential glioma-associated tumor antigen expression profiles of human glioma cells grown in hypoxia.

    PubMed

    Ge, Lisheng; Cornforth, Andrew N; Hoa, Neil T; Delgado, Christina; Chiou, Shiun Kwei; Zhou, Yi Hong; Jadus, Martin R

    2012-01-01

    Human U251 and D54 glioma cells were tested for expression of 25 glioma-associated tumor antigen precursor proteins (TAPP) under hypoxic (1% O(2)) or normoxic (21% O(2)) conditions. Hypoxic glioma cell lines increased their mRNA expression for nine TAPP (Aim2, Art-4, EphA2, EZH2, Fosl1, PTH-rP, Sox 11, Whsc2 and YKL-40), as assessed by quantitative reverse transcriptase real-time/polymerase chain reaction (qRT-PCR). Increased differences with three hypoxic-induced TAPP: EZH2, Whsc2 and YKL-40 were shown at the protein levels by fluorescent antibody staining and quantitative electrophoretic analysis. Two TAPP (MRP3 and Trp1) were down-regulated by hypoxia in glioma cell lines. Growing the glioma cells under hypoxia for 13 days, followed by returning them back to normoxic conditions for 7 days, and restored the original normoxic TAPP profile. Thus, hypoxia was an environmental factor that stimulated the transient expression of these antigens. Intracranial xenografts grown in nude mice derived from U251 cells that had been cultured under neurosphere stem cell conditions showed increased expression of Whsc2 or YKL-40, demonstrating that these in vitro properties of glioma also occur in vivo. Whsc2-specific cytotoxic T lymphocytes killed the hypoxic U251 glioma cells better than normoxic glioma cells. The antigens expressed by hypoxic tumor cells may be a better source of starting tumor material for loading dendritic cells for novel immunotherapy of glioma using tumor-associated antigens.

  17. Anticancer effect of eupatilin on glioma cells through inhibition of the Notch-1 signaling pathway

    PubMed Central

    WANG, YAWEI; HOU, HONGWEI; LI, MING; YANG, YANG; SUN, LAN

    2016-01-01

    Eupatilin, one of the major flavonoids in Artemisia asiatica Nakai (Asteraceae), has been reported to possess antitumor properties. However, thus far there have been no reports regarding the effects of eupatilin on glioma. Therefore, in the current study the effects of eupatilin on glioma and the underlying molecular mechanism were explored. The effect of eupatilin on cell viability was detected by the MTT assay. Cell invasion and migration were performed with Transwell assays and cell apoptosis was determined by flow cytometric analysis. Notch-1 knockdown cells were established by transfection with Notch-1 small interfering RNA (siRNA). The expression levels of Notch-1 were detected by quantitative reverse transcription-polymerase chain reaction and western blotting. The results of the present study indicated that eupatilin exhibits an anticancer effect on glioma cells. Eupatilin inhibited proliferation, reduced cell invasion and migration, and promoted the apoptosis of glioma cells. Additionally, it suppressed Notch-1 expression. Knockdown of Notch-1 by siRNA contributed to the inhibitory effect of eupatilin on proliferation and invasion of glioma cells. In conclusion, eupatilin had an inhibitory effect on proliferation, invasion and migration, and promoted apoptosis of glioma cells through suppression of the Notch-1 signaling pathway. Therefore, eupatilin may have potential as an effective agent for the treatment of glioma. PMID:26676446

  18. EFEMP2 is upregulated in gliomas and promotes glioma cell proliferation and invasion

    PubMed Central

    Wang, Long; Chen, Qianxue; Chen, Zhibiao; Tian, Daofeng; Xu, Haitao; Cai, Qiang; Liu, Baohui; Deng, Gang

    2015-01-01

    Gliomas are the most common and aggressive form of primary brain tumor. Although EGF-containing fibulin-like extracellular matrix protein 2 (EFEMP2), an extracellular matrix (ECM) glycoprotein, is regarded as a candidate oncogene, little is known about the association of EFEMP2 and gliomas. Here, the expression of EFEMP2 was significantly increased in glioma tissues (n=60) compared to non-tumorous brain tissues (n=25). Silencing of EFEMP2 expression through RNA interference in two glioma cell lines (U87 and U373) remarkably inhibited cell proliferation and G1/S transition. More importantly, EFEMP2 silencing significantly induced cell apoptosis via increasing the ratio of Bax and Bcl-2. Additionally, knockdown of EFEMP2 significantly inhibited the invasive ability of both glioma cells, which was associated with the downregulated expression of metalloproteinase-2 (MMP-2) and MMP-9. In conclusion, expression of EFEMP2 was associated with the oncogenic potential of gliomas and silencing of its expression can suppress cancer cell growth and metastasis. Inhibition of EFEMP2 may be a therapeutic strategy for gliomas. PMID:26617746

  19. MiR-221/222 promote human glioma cell invasion and angiogenesis by targeting TIMP2.

    PubMed

    Yang, Fan; Wang, Wei; Zhou, Chunhui; Xi, Wenjin; Yuan, Lu; Chen, Xu; Li, Yufang; Yang, Angang; Zhang, Jianning; Wang, Tao

    2015-05-01

    miR-221/222 are two highly homologous microRNAs that are frequently upregulated in solid tumors. However, the effects of miR-221/222 in malignant gliomas have not been investigated thoroughly. In this study, we found that miR-221/222 were significantly upregulated in human glioma samples and glioma cell lines. Both gain- and loss-of-function studies showed that miR-221/222 regulate cell proliferation, the cell cycle and apoptosis, in addition to, invasion, metastasis, and angiogenesis in glioma cell lines. Subsequent investigations revealed that TIMP2 is a direct target of miR-221/222, and overexpression of TIMP2 reduced the miR-221/222-mediated invasion, metastasis, and angiogenesis of glioma cells. Taken together, our results suggest that the suppression of miR-221/222 may be a feasible approach for inhibiting the malignant behaviors of glioma.

  20. Bromelain Reversibly Inhibits Invasive Properties of Glioma Cells

    PubMed Central

    Tysnes, Berit B; Maurer, H Rainer; Porwol, Torsten; Probst, Beatrice; Bjerkvig, Rolf; Hoover, Frank

    2001-01-01

    Abstract Bromelain is an aqueous extract from pineapple stem that contains proteinases and exhibits pleiotropic therapeutic effects, i.e., antiedematous, antiinflammatory, antimetastatic, antithrombotic, and fibrinolytic activities. In this study, we tested bromelain's effects on glioma cells to assess whether bromelain could be a potential contributor to new antiinvasive strategies for gliomas. Several complementary assays demonstrated that bromelain significantly and reversibly reduced glioma cell adhesion, migration, and invasion without affecting cell viability, even after treatment periods extending over several months. Immunohistochemistry and immunoblotting experiments demonstrated that α3 and β1 integrin subunits and hyaluronan receptor CD44 protein levels were reduced within 24 hours of bromelain treatment. These effects were not reflected at the RNA level because RNA profiling did not show any significant effects on gene expression. Interestingly, metabolic labelling with 35-S methionine demonstrated that de novo protein synthesis was greatly attenuated by bromelain, in a reversible manner. By using a trans-activating signaling assay, we found that CRE-mediated signaling processes were suppressed. These results indicate that bromelain exerts its antiinvasive effects by proteolysis, signaling cascades, and translational attenuation. PMID:11774029

  1. M2-like tumor-associated macrophages drive vasculogenic mimicry through amplification of IL-6 expression in glioma cells

    PubMed Central

    Zhang, Lin; Xu, Yangyang; Sun, Jintang; Chen, Weiliang; Zhao, Lei; Ma, Chao; Wang, Qingjie; Sun, Jia; Huang, Bin; Zhang, Yun; Li, Xingang; Qu, Xun

    2017-01-01

    Vasculogenic mimicry (VM) has offered a new horizon for understanding tumor angiogenesis, but the mechanisms of VM in glioma progression have not been studied explicitly until now. As a significant component of immune infiltration in tumor microenvironment, macrophages have been demonstrated to play an important role in tumor growth and angiogenesis. However, whether macrophages could play a potential key role in glioma VM is still poorly understood. Herein we reported that both VM and CD163+ cells were associated with WHO grade and reduced patient survival, and VM channel counting was correlated to the number of infiltrated CD163+ cells in glioma specimens. In vitro studies of glioma cell lines implicated that M2-like macrophages (M2) promoted glioma VM. We found that conditional medium derived from M2 amplified IL-6 expression in glioma cells. Furthermore, our data indicated that IL-6 could promote glioma VM, as blocking IL-6 with neutralizing antibodies abrogated M2-mediated VM enhancement. In addition, the potent PKC inhibitor bisindolylmaleimide I could prevent M2-induced IL-6 upregulation and further inhibited glioma VM facilitation. Taken together, our results suggested that M2-like macrophages drove glioma VM through amplifying IL-6 secretion in glioma cells via PKC pathway. PMID:27903982

  2. Over-expression of tetraspanin 8 in malignant glioma regulates tumor cell progression

    SciTech Connect

    Pan, Si-Jian; Wu, Yue-Bing; Cai, Shang; Pan, Yi-Xin; Liu, Wei; Bian, Liu-Guan; Sun, Bomin; Sun, Qing-Fang

    2015-03-13

    Tumor cell invasion and proliferation remain the overwhelming causes of death for malignant glioma patients. To establish effective therapeutic methods, new targets implied in these processes have to be identified. Tetraspanin 8 (Tspn8) forms complexes with a large variety of trans-membrane and/or cytosolic proteins to regulate several important cellular functions. In the current study, we found that Tspn8 was over-expressed in multiple clinical malignant glioma tissues, and its expression level correlated with the grade of tumors. Tspn8 expression in malignant glioma cells (U251MG and U87MG lines) is important for cell proliferation and migration. siRNA-mediated knockdown of Tspn8 markedly reduced in vitro proliferation and migration of U251MG and U87MG cells. Meanwhile, Tspn8 silencing also increased the sensitivity of temozolomide (TMZ), and significantly increased U251MG or U87MG cell death and apoptosis by TMZ were achieved with Tspn8 knockdown. We observed that Tspn8 formed a complex with activated focal adhesion kinase (FAK) in both human malignant glioma tissues and in above glioma cells. This complexation appeared required for FAK activation, since Tspn8 knockdown inhibited FAK activation in U251MG and U87MG cells. These results provide evidence that Tspn8 contributes to the pathogenesis of glioblastoma probably by promoting proliferation, migration and TMZ-resistance of glioma cells. Therefore, targeting Tspn8 may provide a potential therapeutic intervention for malignant glioma. - Highlights: • Tspn8 is over-expressed in multiple clinical malignant glioma tissues. • Tspn8 expression is correlated with the grade of malignant gliomas. • Tspn8 knockdown suppresses U251MG/U87MG proliferation and in vitro migration. • Tspn8 knockdown significantly increases TMZ sensitivity in U251MG/U87MG cells. • Tspn8 forms a complex with FAK, required for FAK activation.

  3. MiRNA expression profiling in human gliomas: upregulated miR-363 increases cell survival and proliferation.

    PubMed

    Conti, Alfredo; Romeo, Sara G; Cama, Annamaria; La Torre, Domenico; Barresi, Valeria; Pezzino, Gaetana; Tomasello, Chiara; Cardali, Salvatore; Angileri, Filippo F; Polito, Francesca; Ferlazzo, Guido; Di Giorgio, Rosamaria; Germanò, Antonino; Aguennouz, M'hammed

    2016-10-01

    The role of microRNAs (miRNAs) in glioma biology is increasingly recognized. To investigate the regulatory mechanisms governing the malignant signature of gliomas with different grades of malignancy, we analyzed miRNA expression profiles in human grade I-IV tumor samples and primary glioma cell cultures. Multiplex real-time PCR was used to profile miRNA expression in a set of World Health Organization (WHO) grade I (pilocytic astrocytoma), II (diffuse fibrillary astrocytoma), and IV (glioblastoma multiforme) astrocytic tumors and primary glioma cell cultures. Primary glioma cell cultures were used to evaluate the effect of transfection of specific miRNAs and miRNA inhibitors. miRNA microarray showed that a set of miRNAs was consistently upregulated in all glioma samples. miR-363 was upregulated in all tumor specimens and cell lines, and its expression correlated with tumor grading. The transfection of glioma cells with the specific inhibitor of miR-363 increased the expression level of tumor suppressor growth-associated protein 43 (GAP-43). Transfection of miR-363 induced cell survival, while inhibition of miR-363 significantly reduced glioma cell viability. Furthermore, miRNA-363 inhibition induced the downregulation of AKT, cyclin-D1, matrix metalloproteinase (MMP)-2, MMP-9, and Bcl-2 and upregulation of caspase 3. Together, these data suggest that the upregulation of miR-363 may play a role in malignant glioma signature.

  4. Proapoptotic and antiinvasive activity of Rac1 small molecule inhibitors on malignant glioma cells

    PubMed Central

    Cardama, Georgina A; Gonzalez, Nazareno; Ciarlantini, Matias; Gandolfi Donadío, Lucia; Comin, María Julieta; Alonso, Daniel F; Menna, Pablo Lorenzano; Gomez, Daniel E

    2014-01-01

    Malignant gliomas are characterized by an intrinsic ability to invade diffusely throughout the normal brain tissue. This feature contributes mainly to the failure of existing therapies. Deregulation of small GTPases signaling, in particular Rac1 activity, plays a key role in the invasive phenotype of gliomas. Here we report the effect of ZINC69391, a specific Rac1 inhibitor developed by our group, on human glioma cell lines LN229 and U-87 MG. ZINC69391 is able to interfere with the interaction of Rac1 with Dock180, a relevant Rac1 activator in glioma invasion, and to reduce Rac1-GTP levels. The kinase Pak1, a downstream effector of Dock180–Rac1 signaling, was also downregulated upon ZINC69391 treatment. ZINC69391 reduced cell proliferation, arrested cells in G1 phase, and triggered apoptosis in glioma cells. Importantly, ZINC69391 dramatically affected cell migration and invasion in vitro, interfering with actin cytoskeleton dynamics. We also evaluated the effect of analog 1A-116, a compound derived from ZINC69391 structure. 1A-116 showed an improved antiproliferative and antiinvasive activity on glioma cells. These findings encourage further preclinical testing in clinically relevant animal models. PMID:25378937

  5. Low Expression of CAPON in Glioma Contributes to Cell Proliferation via the Akt Signaling Pathway

    PubMed Central

    Gao, Shangfeng; Wang, Jie; Zhang, Tong; Liu, Guangping; Jin, Lei; Ji, Daofei; Wang, Peng; Meng, Qingming; Zhu, Yufu; Yu, Rutong

    2016-01-01

    CAPON is an adapter protein for nitric oxide synthase 1 (NOS1). CAPON has two isoforms in the human brain: CAPON-L (long form of CAPON) and CAPON-S (short form of CAPON). Recent studies have indicated the involvement of CAPON in tumorigenesis beyond its classical role in NOS1 activity regulation. In this study, we found that the protein levels of CAPON-S, but not than CAPON-L, were significantly decreased in glioma tissues. Therefore, we established lentivirus-mediated stable cell lines with CAPON-S overexpression or down-regulation, and investigated the role of CAPON-S in the proliferation of glioma cells by using CCK8, EdU, and flow cytometry assays. Overexpression of CAPON-S reduced the cell variability and the percentage of EdU-positive cells, and arrested the cells in the G1 phase in glioma cells. Silencing of CAPON by short-hairpin RNA showed the opposite effects. Furthermore, an intracellular signaling array revealed that overexpression of CAPON-S resulted in a remarkable reduction in the phosphorylation of Akt and S6 ribosomal protein in glioma cells, which was further confirmed by Western blot. These findings suggest that CAPON may function as a tumor suppressor in human brain glioma and that the inactivation of the Akt signaling pathway caused by CAPON-S overexpression may provide insight into the underlying mechanism of CAPON in glioma cell proliferation. PMID:27869735

  6. Glioma cell VEGFR-2 confers resistance to chemotherapeutic and antiangiogenic treatments in PTEN-deficient glioblastoma.

    PubMed

    Kessler, Tobias; Sahm, Felix; Blaes, Jonas; Osswald, Matthias; Rübmann, Petra; Milford, David; Urban, Severino; Jestaedt, Leonie; Heiland, Sabine; Bendszus, Martin; Hertenstein, Anne; Pfenning, Philipp-Niclas; Ruiz de Almodóvar, Carmen; Wick, Antje; Winkler, Frank; von Deimling, Andreas; Platten, Michael; Wick, Wolfgang; Weiler, Markus

    2015-10-13

    Loss of the tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a prerequisite for tumor cell-specific expression of vascular endothelial growth factor receptor (VEGFR)-2 in glioblastoma defining a subgroup prone to develop evasive resistance towards antiangiogenic treatments. Immunohistochemical analysis of human tumor tissues showed VEGFR-2 expression in glioma cells in 19% of specimens examined, mainly in the infiltration zone. Glioma cell VEGFR-2 positivity was restricted to PTEN-deficient tumor specimens. PTEN overexpression reduced VEGFR-2 expression in vitro, as well as knock-down of raptor or rictor. Genetic interference with VEGFR-2 revealed proproliferative, antiinvasive and chemoprotective functions for VEGFR-2 in glioma cells. VEGFR-2-dependent cellular effects were concomitant with activation of 'kappa-light-chain-enhancer' of activated B-cells, protein kinase B, and N-myc downstream regulated gene 1. Two-photon in vivo microscopy revealed that expression of VEGFR-2 in glioma cells hampers antiangiogenesis. Bevacizumab induces a proinvasive response in VEGFR-2-positive glioma cells. Patients with PTEN-negative glioblastomas had a shorter survival after initiation of bevacizumab therapy compared with PTEN-positive glioblastomas. Conclusively, expression of VEGFR-2 in glioma cells indicates an aggressive glioblastoma subgroup developing early resistance to temozolomide or bevacizumab. Loss of PTEN may serve as a biomarker identifying those tumors upfront by routine neuropathological methods.

  7. Dexamethasone differentially regulates functional membrane properties in glioma cell lines and primary astrocytes in vitro.

    PubMed

    Hinkerohe, Daniel; Wolfkühler, Dörte; Haghikia, Aiden; Meier, Carola; Faustmann, Pedro M; Schlegel, Uwe

    2011-07-01

    Similar to astrocytes, glioma cells form a well-coupled syncytium via gap junctions. This can be influenced, for example, by activated microglia, the main inflammatory cell population within the central nervous system (CNS). Under pathological conditions such as neoplastic cell growth, microglia number and activation state are enhanced. The aim of the present study is to analyze the influence of dexamethasone (DEX) on cellular and molecular properties in glial coculture models consisting of astroglia and microglia and human and rat glioma cell lines. Primary rat glial cocultures of astrocytes containing 5% (M5, representing "physiological" conditions) or 30% (M30, representing "pathological" conditions) microglia as well as rat and human glioma cell lines (F98, C6, U87) were incubated with DEX for 24 h. DEX-treated M30 cocultures showed significant increased gap junctional intercellular communication (GJIC). DEX treatment of glioma cells resulted in depolarization of the membrane resting potential (MRP) and a significant reduction of GJIC. Furthermore, DEX reduced the amount of activated microglia in M30 cocultures. DEX had no significant effects on the tested variables in the M5 coculture. DEX differentially regulates functional membrane properties of glioma cells and astrocytes in primary glial cocultures, which might resemble steroid effects in glioma cells and adjacent glial components in vivo.

  8. Androglobin knockdown inhibits growth of glioma cell lines

    PubMed Central

    Huang, Bo; Lu, Yi-Sheng; Li, Xia; Zhu, Zhi-Chuan; Li, Kui; Liu, Ji-Wei; Zheng, Jing; Hu, Ze-Lan

    2014-01-01

    Globin family was famous for oxygen supply function of its members such as hemoglobin and myoglobin. With the progress of research, several members of this protein family have been proven to play roles in tumors including glioma. Androglobin (ADGB) is a recently identified member of globin family with very few studies about its function. In the present study, we show that ADGB plays an oncogene role in glioma. Lentiviral vector mediated ADGB knockdown inhibited the proliferation of glioma cell lines determined by MTT assay and colony formation assay. ADGB knockdown also increased the apoptosis of glioma cell line U251 assessed by flow cytometry. In addition, western blot showed that ADGB knockdown altered levels of several proteins related to proliferation, survival or apoptosis in U251 cells. These findings suggest ADGB is involved in the progression of glioma in vitro. PMID:24966926

  9. CXCR4 increases in-vivo glioma perivascular invasion, and reduces radiation induced apoptosis: A genetic knockdown study

    PubMed Central

    Yadav, Viveka Nand; Zamler, Daniel; Baker, Gregory J.; Kadiyala, Padma; Erdreich-Epstein, Anat; DeCarvalho, Ana C.; Mikkelsen, Tom; Castro, Maria G.; Lowenstein, Pedro R.

    2016-01-01

    Glioblastoma (GBM) is a highly invasive brain tumor. Perivascular invasion, autovascularization and vascular co-option occur throughout the disease and lead to tumor invasion and progression. The molecular basis for perivascular invasion, i.e., the interaction of glioma tumor cells with endothelial cells is not well characterized. Recent studies indicate that glioma cells have increased expression of CXCR4. We investigated the in-vivo role of CXCR4 in perivascular invasion of glioma cells using shRNA-mediated knock down of CXCR4. We show that primary cultures of human glioma stem cells HF2303 and mouse glioma GL26-Cit cells exhibit significant migration towards human (HBMVE) and mouse (MBVE) brain microvascular endothelial cells. Blocking CXCR4 on tumor cells with AMD3100 in-vitro, inhibits migration of GL26-Cit and HF2303 toward MBVE and HBMVE cells. Additionally, genetic down regulation of CXCR4 in mouse glioma GL26-Cit cells inhibits their in-vitro migration towards MBVE cells; in an in-vivo intracranial mouse model, these cells display reduced tumor growth and perivascular invasion, leading to increased survival. Quantitative analysis of brain sections showed that CXCR4 knockdown tumors are less invasive. Lastly, we tested the effects of radiation on CXCR4 knock down GL26-Cit cells in an orthotopic brain tumor model. Radiation treatment increased apoptosis of CXCR4 downregulated tumor cells and prolonged median survival. In summary, our data suggest that CXCR4 signaling is critical for perivascular invasion of GBM cells and targeting this receptor makes tumors less invasive and more sensitive to radiation therapy. Combination of CXCR4 knock down and radiation treatment might improve the efficacy of GBM therapy. PMID:27863376

  10. Sirt2 suppresses glioma cell growth through targeting NF-κB–miR-21 axis

    SciTech Connect

    Li, Ya’nan; Dai, Dongwei; Lu, Qiong; Fei, Mingyu; Li, Mengmeng; Wu, Xi

    2013-11-22

    Highlights: •Sirt2 expression is down-regulated in human glioma tissues and cell lines. •Sirt2 regresses glioma cell growth and colony formation via inducing apoptosis. •miR-21 is essential for the functions of Sirt2 in glioma cells. •Sirt2 deacetylates p65 to decrease miR-21 expression. -- Abstract: Sirtuins are NAD{sup +}-dependent deacetylases that regulate numerous cellular processes including aging, DNA repair, cell cycle, metabolism, and survival under stress conditions. The roles of sirtuin family members are widely studied in carcinogenesis. However, their roles in glioma remain unclear. Here we report that Sir2 was under expressed in human glioma tissues and cell lines. We found that Sirt2 overexpression decreased cell proliferation and colony formation capacity. In addition, Sirt2 overexpression induced cellular apoptosis via up-regulating cleaved caspase 3 and Bax, and down-regulating anti-apoptotic protein Bcl-2. Sirt2 knockdown obtained opposing results. We showed that Sirt2 overexpression inhibited miR-21 expression, and Sirt2 was not sufficient to reduce cell proliferation and colony formation as well as to induce apoptosis when miR-21 was knocked down in glioma cells. Mechanically, we demonstrated that Sirt2 deacetylated p65 at K310 and blocked p65 binding to the promoter region of miR-21, thus regressing the transcription of miR-21. In summary, Sirt2 is critical in human glioma via NF-κB–miR-21 pathway and Sirt2 activator may serve as candidate drug for glioma therapy.

  11. Glioma Stemlike Cells Enhance the Killing of Glioma Differentiated Cells by Cytotoxic Lymphocytes

    PubMed Central

    Bassoy, Esen Yonca; Chiusolo, Valentina; Jacquemin, Guillaume; Riccadonna, Cristina; Walker, Paul R.; Martinvalet, Denis

    2016-01-01

    Glioblastoma multiforme, the most aggressive primary brain tumor, is maintained by a subpopulation of glioma cells with self-renewal properties that are able to recapitulate the entire tumor even after surgical resection or chemo-radiotherapy. This typifies the vast heterogeneity of this tumor with the two extremes represented on one end by the glioma stemlike cells (GSC) and on the other by the glioma differentiated cells (GDC). Interestingly, GSC are more sensitive to immune effector cells than the GDC counterpart. However, how GSC impact on the killing on the GDC and vice versa is not clear. Using a newly developed cytotoxicity assay allowing to simultaneously monitor cytotoxic lymphocytes-mediated killing of GSC and GDC, we found that although GSC were always better killed and that their presence enhanced the killing of GDC. In contrast, an excess of GDC had a mild protective effect on the killing of GSC, depending on the CTL type. Overall, our results suggest that during combination therapy, immunotherapy would be the most effective after prior treatment with conventional therapies. PMID:27073883

  12. Hugl-1 inhibits glioma cell growth in intracranial model.

    PubMed

    Liu, Xuejiao; Lu, Dong; Ma, Peng; Liu, Huaqiang; Cao, Yuewen; Sang, Ben; Zhu, Xianlong; Shi, Qiong; Hu, Jinxia; Yu, Rutong; Zhou, Xiuping

    2015-10-01

    Drosophila lethal (2) giant larvae (lgl) has been reported as a tumor suppressor and could regulate the Drosophila hippo signaling. Human giant larvae-1(Hugl-1), one human homologue of Drosophila lgl, also has been reported to be involved in the development of some human cancers. However, whether Hugl-1 is associated with the pathogenesis of malignant gliomas remains poorly understood. In the present work, we examined the effect of Hugl-1 on glioma cell growth both in vitro and in vivo. Firstly, we found that Hugl-1 protein levels decreased in the human glioma tissues, suggesting that Hugl-1 is involved in glioma progression. Unfortunately, either stably or transiently over-expressing Hugl-1 did not affect glioma cell proliferation in vitro. In addition, Hugl-1 over-expression did not regulate hippo signaling pathway. Interestingly, over-expression of Hugl-1 not only inhibited gliomagenesis but also markedly inhibited cell proliferation and promoted the apoptosis of U251 cells in an orthotopic model of nude mice. Taken together, this study provides the evidence that Hugl-1 inhibits glioma cell growth in intracranial model of nude mice, suggesting that Hugl-1 might be a potential tumor target for glioma therapy.

  13. Three-dimensional cultured glioma cell lines

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R. (Inventor); Marley, Garry M. (Inventor)

    1991-01-01

    Three-dimensional glioma spheroids were produced in vitro with size and histological differentiation previously unattained. The spheroids were grown in liquid media suspension in a Johnson Space Center (JSC) Rotating Wall Bioreactor without using support matrices such as microcarrier beads. Spheroid volumes of greater than 3.5 cu mm and diameters of 2.5 mm were achieved with a viable external layer or rim of proliferating cells, a transitional layer beneath the external layer with histological differentiation, and a degenerative central region with a hypoxic necrotic core. Cell debris was evident in the degenerative central region. The necrotics centers of some of the spheroids had hyaline droplets. Granular bodies were detected predominantly in the necrotic center.

  14. Control of glioma cell migration and invasiveness by GDF-15.

    PubMed

    Codó, Paula; Weller, Michael; Kaulich, Kerstin; Schraivogel, Daniel; Silginer, Manuela; Reifenberger, Guido; Meister, Gunter; Roth, Patrick

    2016-02-16

    Growth and differentiation factor (GDF)-15 is a member of the transforming growth factor (TGF)-β family of proteins. GDF-15 levels are increased in the blood and cerebrospinal fluid of glioblastoma patients. Using a TCGA database interrogation, we demonstrate that high GDF-15 expression levels are associated with poor survival of glioblastoma patients. To elucidate the role of GDF-15 in glioblastoma in detail, we confirmed that glioma cells express GDF-15 mRNA and protein in vitro. To allow for a detailed functional characterization, GDF-15 expression was silenced using RNA interference in LNT-229 and LN-308 glioma cells. Depletion of GDF-15 had no effect on cell viability. In contrast, GDF-15-deficient cells displayed reduced migration and invasion, in the absence of changes in Smad2 or Smad1/5/8 phosphorylation. Conversely, exogenous GDF-15 stimulated migration and invasiveness. Large-scale expression profiling revealed that GDF-15 gene silencing resulted in minor changes in the miRNA profile whereas several genes, including members of the plasminogen activator/inhibitor complex, were deregulated at the mRNA level. One of the newly identified genes induced by GDF-15 gene silencing was the serpin peptidase inhibitor, clade E nexin group 1 (serpine1) which is induced by TGF-β and known to inhibit migration and invasiveness. However, serpine1 down-regulation alone did not mediate GDF-15-induced promotion of migration and invasiveness. Our findings highlight the complex contributions of GDF-15 to the invasive phenotype of glioma cells and suggest anti-GDF-15 approaches as a promising therapeutic strategy.

  15. Control of glioma cell migration and invasiveness by GDF-15

    PubMed Central

    Codó, Paula; Weller, Michael; Kaulich, Kerstin; Schraivogel, Daniel; Silginer, Manuela; Reifenberger, Guido; Meister, Gunter; Roth, Patrick

    2016-01-01

    Growth and differentiation factor (GDF)-15 is a member of the transforming growth factor (TGF)-β family of proteins. GDF-15 levels are increased in the blood and cerebrospinal fluid of glioblastoma patients. Using a TCGA database interrogation, we demonstrate that high GDF-15 expression levels are associated with poor survival of glioblastoma patients. To elucidate the role of GDF-15 in glioblastoma in detail, we confirmed that glioma cells express GDF-15 mRNA and protein in vitro. To allow for a detailed functional characterization, GDF-15 expression was silenced using RNA interference in LNT-229 and LN-308 glioma cells. Depletion of GDF-15 had no effect on cell viability. In contrast, GDF-15-deficient cells displayed reduced migration and invasion, in the absence of changes in Smad2 or Smad1/5/8 phosphorylation. Conversely, exogenous GDF-15 stimulated migration and invasiveness. Large-scale expression profiling revealed that GDF-15 gene silencing resulted in minor changes in the miRNA profile whereas several genes, including members of the plasminogen activator/inhibitor complex, were deregulated at the mRNA level. One of the newly identified genes induced by GDF-15 gene silencing was the serpin peptidase inhibitor, clade E nexin group 1 (serpine1) which is induced by TGF-β and known to inhibit migration and invasiveness. However, serpine1 down-regulation alone did not mediate GDF-15-induced promotion of migration and invasiveness. Our findings highlight the complex contributions of GDF-15 to the invasive phenotype of glioma cells and suggest anti-GDF-15 approaches as a promising therapeutic strategy. PMID:26741507

  16. Histone deacetylase inhibitors promote glioma cell death by G2 checkpoint abrogation leading to mitotic catastrophe.

    PubMed

    Cornago, M; Garcia-Alberich, C; Blasco-Angulo, N; Vall-Llaura, N; Nager, M; Herreros, J; Comella, J X; Sanchis, D; Llovera, M

    2014-10-02

    Glioblastoma multiforme is resistant to conventional anti-tumoral treatments due to its infiltrative nature and capability of relapse; therefore, research efforts focus on characterizing gliomagenesis and identifying molecular targets useful on therapy. New therapeutic strategies are being tested in patients, such as Histone deacetylase inhibitors (HDACi) either alone or in combination with other therapies. Here two HDACi included in clinical trials have been tested, suberanilohydroxamic acid (SAHA) and valproic acid (VPA), to characterize their effects on glioma cell growth in vitro and to determine the molecular changes that promote cancer cell death. We found that both HDACi reduce glioma cell viability, proliferation and clonogenicity. They have multiple effects, such as inducing the production of reactive oxygen species (ROS) and activating the mitochondrial apoptotic pathway, nevertheless cell death is not prevented by the pan-caspase inhibitor Q-VD-OPh. Importantly, we found that HDACi alter cell cycle progression by decreasing the expression of G2 checkpoint kinases Wee1 and checkpoint kinase 1 (Chk1). In addition, HDACi reduce the expression of proteins involved in DNA repair (Rad51), mitotic spindle formation (TPX2) and chromosome segregation (Survivin) in glioma cells and in human glioblastoma multiforme primary cultures. Therefore, HDACi treatment causes glioma cell entry into mitosis before DNA damage could be repaired and to the formation of an aberrant mitotic spindle that results in glioma cell death through mitotic catastrophe-induced apoptosis.

  17. Evaluation of nano-magnetic fluid on malignant glioma cells

    PubMed Central

    Xu, Hongsheng; Zong, Hailiang; Ma, Chong; Ming, Xing; Shang, Ming; Li, Kai; He, Xiaoguang; Cao, Lei

    2017-01-01

    The temperature variation rule of nano-magnetic fluid in the specific magnetic field and the effect on the treatment of malignant glioma were examined. The temperature variation of nano-magnetic fluid in the specific magnetic field was investigated by heating in vitro, and cell morphology was observed through optical microscopy and electron microscopy. MTT detection also was used to detect the effect of Fe3O4 nanometer magnetic fluid hyperthermia (MFH) on the proliferation of human U251 glioma cell line. The Fe3O4 nano MFH experiment was used to detect the inhibition rate of the tumor volume in nude mice with tumors. The results of the experiment showed that the heating ability of magnetic fluid was positively correlated with its concentration at the same intensity of the magnetic field. The results also indicated the prominent inhibitory effect of nanometer MFH on the proliferation of glioma cells, which was a dose-dependent relationship with nanometer magnetic fluid concentration. The hyperthermia experiment of nude mice with tumors displayed a significant inhibiting effect of Fe3O4 nanometer magnetic fluid in glioma volume. These results explain that iron (II, III) oxide (Fe3O4) nanometer MFH can inhibit the proliferation of U251 glioma cells, and has an obvious inhibitory effect on glioma volume, which plays a certain role in the treatment of brain glioma. PMID:28356945

  18. Evaluation of nano-magnetic fluid on malignant glioma cells.

    PubMed

    Xu, Hongsheng; Zong, Hailiang; Ma, Chong; Ming, Xing; Shang, Ming; Li, Kai; He, Xiaoguang; Cao, Lei

    2017-02-01

    The temperature variation rule of nano-magnetic fluid in the specific magnetic field and the effect on the treatment of malignant glioma were examined. The temperature variation of nano-magnetic fluid in the specific magnetic field was investigated by heating in vitro, and cell morphology was observed through optical microscopy and electron microscopy. MTT detection also was used to detect the effect of Fe3O4 nanometer magnetic fluid hyperthermia (MFH) on the proliferation of human U251 glioma cell line. The Fe3O4 nano MFH experiment was used to detect the inhibition rate of the tumor volume in nude mice with tumors. The results of the experiment showed that the heating ability of magnetic fluid was positively correlated with its concentration at the same intensity of the magnetic field. The results also indicated the prominent inhibitory effect of nanometer MFH on the proliferation of glioma cells, which was a dose-dependent relationship with nanometer magnetic fluid concentration. The hyperthermia experiment of nude mice with tumors displayed a significant inhibiting effect of Fe3O4 nanometer magnetic fluid in glioma volume. These results explain that iron (II, III) oxide (Fe3O4) nanometer MFH can inhibit the proliferation of U251 glioma cells, and has an obvious inhibitory effect on glioma volume, which plays a certain role in the treatment of brain glioma.

  19. IGFBP2 promotes glioma tumor stem cell expansion and survival

    SciTech Connect

    Hsieh, David; Hsieh, Antony; Stea, Baldassarre; Ellsworth, Ron

    2010-06-25

    IGFBP2 is overexpressed in the most common brain tumor, glioblastoma (GBM), and its expression is inversely correlated to GBM patient survival. Previous reports have demonstrated a role for IGFBP2 in glioma cell invasion and astrocytoma development. However, the function of IGFBP2 in the restricted, self-renewing, and tumorigenic GBM cell population comprised of tumor-initiating stem cells has yet to be determined. Herein we demonstrate that IGFBP2 is overexpressed within the stem cell compartment of GBMs and is integral for the clonal expansion and proliferative properties of glioma stem cells (GSCs). In addition, IGFBP2 inhibition reduced Akt-dependent GSC genotoxic and drug resistance. These results suggest that IGFBP2 is a selective malignant factor that may contribute significantly to GBM pathogenesis by enriching for GSCs and mediating their survival. Given the current dearth of selective molecular targets against GSCs, we anticipate our results to be of high therapeutic relevance in combating the rapid and lethal course of GBM.

  20. Selective control of human glioma cell proliferation by specific cell interaction.

    PubMed

    MacDonald, C M; Freshney, R I; Hart, E; Graham, D I

    1985-01-01

    Cells cultured from anaplastic astrocytoma (Kernohan and Sayre, grades III and IV) will proliferate on confluent monolayers of normal glia, while cells cultured from normal brain will not. The growth of a cell line containing a high proportion of well-differentiated glioma cells (G-CCM) was partially inhibited, though not as much as normal glia, while the growth of a cell line made up of less differentiated cells (G-UVW) was enhanced by the normal glia. Although non-glial confluent monolayers also inhibited the growth of normal glia, this was less specific, as one normal glial line (N-DUT) grew on fibroblasts and intestinal epithelium, although it was unable to do so on normal glia. It is suggested that this may be a useful method for examining reduced density limitation of growth, discriminating between normal and malignant glia, and for separating glioma cells from contaminating normal cells.

  1. High expression of long noncoding RNA HULC is a poor predictor of prognosis and regulates cell proliferation in glioma

    PubMed Central

    Yan, Hong; Tian, Rui; Zhang, Min; Wu, Jing; Ding, Min; He, Jie

    2017-01-01

    Purpose Emerging studies show that long noncoding RNAs (lncRNAs) have important roles in carcinogenesis. This study investigated the role of lncRNA highly upregulated in liver cancer (HULC) expression in glioma and its clinical significance in glioma patients. Materials and methods HULC expression was detected in glioma tissues and cell lines by using real-time quantitative reverse transcription polymerase chain reactions. Association between HULC levels and clinicopathological factors and patients prognosis was also analyzed. Expression of HULC was restored and knocked down in glioma cell line U87 by using HULC cDNA and siRNA, respectively. CCK-8 and colony formation assays were used to investigate the role of HULC in the regulation of proliferation of glioma cells. Results HULC was highly expressed in glioma tissues, being closely related to age and grade of glioma. Univariate survival analysis demonstrated that high HULC levels were significantly associated with overall survival (OS) (hazard ratio [HR], 0.422; 95% confidence interval [CI], 0.220–0.806; P=0.009), and it remained an independent predictor for OS (HR, 0.340; 95% CI, 0.175–0.659; P=0.001) in multivariate Cox regression analysis. Functionally, forced expression of HULC results in increased cell proliferation and colony formation of U87 glioma cell line, whereas knockdown of HULC expression reduced these oncogenic properties of glioma cells. Conclusion These findings suggest that HULC may play an important role in glioma progression and will be further evaluated as a biomarker for predicting the survival of glioma patients. PMID:28053545

  2. Overexpressed KDM5B is associated with the progression of glioma and promotes glioma cell growth via downregulating p21

    SciTech Connect

    Dai, Bin; Hu, Zhiqiang; Huang, Hui; Zhu, Guangtong; Xiao, Zhiyong; Wan, Weiqing; Zhang, Peng; Jia, Wang; Zhang, Liwei

    2014-11-07

    Highlights: • KDM5B is overexpressed in glioma samples. • KDM5B stimulated proliferation of glioma cells. • Inhibition of p21contributes to KDM5B-induced proliferation. - Abstract: Epigenetic alterations such as aberrant expression of histone-modifying enzymes have been implicated in tumorigenesis. Upregulation of lysine (K)-specific demethylase 5B (KDM5B) has been reported in a variety of malignant tumors. However, the impact of KDM5B in glioma remains unclear. The objective of this study was to investigate the expression and prognostic value of KDM5B in glioma. In clinical glioma samples, we found that KDM5B expression was significantly upregulated in cancer lesions compared with normal brain tissues. Kaplan–Meier analysis showed that patients with glioma and higher KDM5B expression tend to have shorter overall survival time. By silencing or overexpressing KDM5B in glioma cells, we found that KDM5B could promote cell growth both in vitro and in vivo. Moreover, we demonstrated that KDM5B promoted glioma proliferation partly via regulation of the expression of p21. Our study provided evidence that KDM5B functions as a novel tumor oncogene in glioma and may be a potential therapeutic target for glioma management.

  3. Inhibitory effects of pharmacological doses of melatonin on aromatase activity and expression in rat glioma cells.

    PubMed

    González, A; Martínez-Campa, C; Mediavilla, M D; Alonso-González, C; Sánchez-Barceló, E J; Cos, S

    2007-09-17

    Melatonin exerts oncostatic effects on different kinds of neoplasias, especially on oestrogen-dependent tumours. Recently, it has been described that melatonin, on the basis of its antioxidant properties, inhibits the growth of glioma cells. Glioma cells express oestrogen receptors and have the ability to synthesise oestrogens from androgens. In the present study, we demonstrate that pharmacological concentrations of melatonin decreases the growth of C6 glioma cells and reduces the local biosynthesis of oestrogens, through the inhibition of aromatase, the enzyme that catalyses the conversion of androgens into oestrogens. These results are supported by three types of evidence. Firstly, melatonin counteracts the growth stimulatory effects of testosterone on glioma cells, which is dependent on the local synthesis of oestrogens from testosterone. Secondly, we found that melatonin reduces the aromatase activity of C6 cells, measured by the tritiated water release assay. Finally, by (RT)-PCR, we found that melatonin downregulates aromatase mRNA steady-state levels in these glioma cells. We conclude that melatonin inhibits the local production of oestrogens decreasing aromatase activity and expression. By analogy to the implications of aromatase in other forms of oestrogen-sensitive tumours, it is conceivable that the modulation of the aromatase by pharmacological melatonin may play a role in the growth of glioblastomas.

  4. Macrophage Ablation Reduces M2-Like Populations and Jeopardizes Tumor Growth in a MAFIA-Based Glioma Model12

    PubMed Central

    Gabrusiewicz, Konrad; Hossain, Mohammad B.; Cortes-Santiago, Nahir; Fan, Xuejun; Kaminska, Bozena; Marini, Frank C.; Fueyo, Juan; Gomez-Manzano, Candelaria

    2015-01-01

    Monocytes/macrophages are an influential component of the glioma microenvironment. However, understanding their diversity and plasticity constitute one of the most challenging areas of research due to the paucity of models to study these cells' inherent complexity. Herein, we analyzed the role of monocytes/macrophages in glioma growth by using a transgenic model that allows for conditional ablation of this cell population. We modeled glioma using intracranial GL261-bearing CSF-1R–GFP+ macrophage Fas-induced apoptosis (MAFIA) transgenic mice. Conditional macrophage ablation was achieved by exposure to the dimerizer AP20187. Double immunofluorescence was used to characterize M1- and M2-like monocytes/macrophages during tumor growth and after conditional ablation. During glioma growth, the monocyte/macrophage population consisted predominantly of M2 macrophages. Conditional temporal depletion of macrophages reduced the number of GFP+ cells, targeting mainly the repopulation of M2-polarized cells, and altered the appearance of M1-like monocytes/macrophages, which suggested a shift in the M1/M2 macrophage balance. Of interest, compared with control-treated mice, macrophage-depleted mice had a lower tumor mitotic index, microvascular density, and reduced tumor growth. These results demonstrated the possibility of studying in vivo the role and phenotype of macrophages in gliomas and suggested that transitory depletion of CSF-1R+ population influences the reconstitutive phenotypic pool of these cells, ultimately suppressing tumor growth. The MAFIA model provides a much needed advance in defining the role of macrophages in gliomas. PMID:25925380

  5. Malignant glioma: lessons from genomics, mouse models, and stem cells.

    PubMed

    Chen, Jian; McKay, Renée M; Parada, Luis F

    2012-03-30

    Eighty percent of malignant tumors that develop in the central nervous system are malignant gliomas, which are essentially incurable. Here, we discuss how recent sequencing studies are identifying unexpected drivers of gliomagenesis, including mutations in isocitrate dehydrogenase 1 and the NF-κB pathway, and how genome-wide analyses are reshaping the classification schemes for tumors and enhancing prognostic value of molecular markers. We discuss the controversies surrounding glioma stem cells and explore how the integration of new molecular data allows for the generation of more informative animal models to advance our knowledge of glioma's origin, progression, and treatment.

  6. Inhibitory effect of DNA topoisomerase inhibitor isoliquiritigenin on the growth of glioma cells

    PubMed Central

    Zhao, Shupeng; Chang, Haigang; Ma, Pengju; Gao, Guojun; Jin, Cailing; Zhao, Xinli; Zhou, Wenke; Jin, Baozhe

    2015-01-01

    Objective: To investigate the effect of isoliquiritigenin on the activity of DNA topoisomerase (TOP I) and its inhibitory effect on the growth of U87 glioma cells. Methods: This study investigated the inhibitory effect of isoliquiritigenin on the growth of U87 glioma cells and its cytotoxicity by MTT method and determined the effect of isoliquiritigenin on TOP I activity by agarose gel electrophoresis. On this basis, we studied the interaction between isoliquiritigenin and TOP I and DNA. Finally, we further discussed the effect of isoliquiritigenin on the activity of Caspase 3, the apoptosis protein of U87 glioma cells. Results: Isoliquiritigenin could inhibit the growth of U87 glioma cells (half inhibitory concentration IC50: 0.221 mM) and is of low cytotoxicity to normal cells. Agarose gel electrophoresis showed that isoliquiritigenin had significant inhibitory effect on TOP I activity. Molecular simulation results indicated that isoliquiritigenin took priority of binding to the active center of TOP I, and formed hydrogen bonds with the catalytic site Try723. Finally, Caspase 3 activity detection results suggested that isoliquiritigenin could significantly increase the activity of Caspase 3 (P < 0.05). Conclusion: Isoliquiritigenin had a reversible inhibitory effect on TOP I activity, reduced the rate of single strand DNA unwinding in tumor cells, and thus played an important role in inducing the apoptosis of U87 glioma cells. PMID:26722447

  7. Armodafinil in Reducing Cancer-Related Fatigue in Patients With High Grade Glioma | Division of Cancer Prevention

    Cancer.gov

    This randomized phase III trial studies armodafinil to see how well it works in reducing cancer-related fatigue in patients with high grade glioma. Armodafinil may help relieve fatigue in patients with high grade glioma. |

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

    PubMed

    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.

  9. Arctigenin, a natural lignan compound, induces G0/G1 cell cycle arrest and apoptosis in human glioma cells

    PubMed Central

    Maimaitili, Aisha; Shu, Zunhua; Cheng, Xiaojiang; Kaheerman, Kadeer; Sikandeer, Alifu; Li, Weimin

    2017-01-01

    The aim of the current study was to investigate the anticancer potential of arctigenin, a natural lignan compound, in malignant gliomas. The U87MG and T98G human glioma cell lines were treated with various concentrations of arctigenin for 48 h and the effects of arctigenin on the aggressive phenotypes of glioma cells were assessed. The results demonstrated that arctigenin dose-dependently inhibited the growth of U87MG and T98G cells, as determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and bromodeoxyuridine incorporation assays. Arctigenin exposure also induced a 60–75% reduction in colony formation compared with vehicle-treated control cells. However, arctigenin was not observed to affect the invasiveness of glioma cells. Arctigenin significantly increased the proportion of cells in the G0/G1 phase and reduced the number of cells in the S phase, as compared with the control group (P<0.05). Western blot analysis demonstrated that arctigenin increased the expression levels of p21, retinoblastoma and p53 proteins, and significantly decreased the expression levels of cyclin D1 and cyclin-dependent kinase 4 proteins. Additionally, arctigenin was able to induce apoptosis in glioma cells, coupled with increased expression levels of cleaved caspase-3 and the pro-apoptotic BCL2-associated X protein. Furthermore, arctigenin-induced apoptosis was significantly suppressed by the pretreatment of cells with Z-DEVD-FMK, a caspase-3 inhibitor. In conclusion, the results suggest that arctigenin is able to inhibit cell proliferation and may induce apoptosis and cell cycle arrest at the G0/G1 phase in glioma cells. These results warrant further investigation of the anticancer effects of arctigenin in animal models of gliomas. PMID:28356992

  10. Arctigenin, a natural lignan compound, induces G0/G1 cell cycle arrest and apoptosis in human glioma cells.

    PubMed

    Maimaitili, Aisha; Shu, Zunhua; Cheng, Xiaojiang; Kaheerman, Kadeer; Sikandeer, Alifu; Li, Weimin

    2017-02-01

    The aim of the current study was to investigate the anticancer potential of arctigenin, a natural lignan compound, in malignant gliomas. The U87MG and T98G human glioma cell lines were treated with various concentrations of arctigenin for 48 h and the effects of arctigenin on the aggressive phenotypes of glioma cells were assessed. The results demonstrated that arctigenin dose-dependently inhibited the growth of U87MG and T98G cells, as determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and bromodeoxyuridine incorporation assays. Arctigenin exposure also induced a 60-75% reduction in colony formation compared with vehicle-treated control cells. However, arctigenin was not observed to affect the invasiveness of glioma cells. Arctigenin significantly increased the proportion of cells in the G0/G1 phase and reduced the number of cells in the S phase, as compared with the control group (P<0.05). Western blot analysis demonstrated that arctigenin increased the expression levels of p21, retinoblastoma and p53 proteins, and significantly decreased the expression levels of cyclin D1 and cyclin-dependent kinase 4 proteins. Additionally, arctigenin was able to induce apoptosis in glioma cells, coupled with increased expression levels of cleaved caspase-3 and the pro-apoptotic BCL2-associated X protein. Furthermore, arctigenin-induced apoptosis was significantly suppressed by the pretreatment of cells with Z-DEVD-FMK, a caspase-3 inhibitor. In conclusion, the results suggest that arctigenin is able to inhibit cell proliferation and may induce apoptosis and cell cycle arrest at the G0/G1 phase in glioma cells. These results warrant further investigation of the anticancer effects of arctigenin in animal models of gliomas.

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

    PubMed

    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.

  12. Stem cell-mediated delivery of therapies in the treatment of glioma.

    PubMed

    Frosina, G

    2011-06-01

    High grade gliomas can be seldom controlled, due to the infiltrative nature of these tumors and the presence of cell populations resistant to radio- and chemotherapy. Current research aims to develop novel therapeutic approaches to track and eliminate the disseminated glioma-driving cells. Selected delivery of therapeutic agents taking advantage of the tropism of normal stem cells for glioma cells might be one.

  13. miR-218 inhibits the invasive ability of glioma cells by direct downregulation of IKK-{beta}

    SciTech Connect

    Song, Libing; Huang, Quan; Chen, Kun; Liu, Liping; Lin, Chuyong; Dai, Ting; Yu, Chunping; Wu, Zhiqiang; Li, Jun

    2010-11-05

    Research highlights: {yields} miR-218 is markedly downregulated in glioma cell lines and in primary glioma tissues. {yields} Upregulation of miR-218 dramatically reduces the invasive ability of glioma cells. {yields} Ectopic expression of miR-218 inactivates IKK-{beta}/NF-{kappa}B signaling pathway. {yields} miR-218 directly targets the 3'-untranslated region (3'-UTR) of IKK-{beta}. -- Abstract: Aberrant activation of nuclear factor-kappa B (NF-{kappa}B) pathway has been proven to play important roles in the development and progression of cancers. Activation of NF-{kappa}B via the classical pathway is modulated by I{kappa}Bs kinase (IKK-{beta}). However, the mechanism underlying the epigenetic regulation of IKK-{beta}/NF-{kappa}B pathway remains largely unknown. In this study, we found that the expression level of miR-218 was markedly downregulated in glioma cell lines and in human primary glioma tissues. Upregulation of miR-218 dramatically reduced the migratory speed and invasive ability of glioma cells. Furthermore, we showed that ectopically expressing miR-218 in glioma cells resulted in downregulation of matrix metalloproteinase-9 (MMP-9) and reduction in NF-{kappa}B transactivity at a transcriptional level, but inhibition of miR-218 enhanced the expression of MMP-9 and transcriptional activity of NF-{kappa}B. Moreover, we showed that miR-218 inactivated the NF-{kappa}B pathway through downregulating IKK-{beta} expression by directly targeting the 3'-untranslated region (3'-UTR) of IKK-{beta}. Taken together, our results suggest that miR-218 plays an important role in preventing the invasiveness of glioma cells, and our results present a novel mechanism of miRNA-mediated direct suppression of IKK-{beta}/NF-{kappa}B pathway in gliomas.

  14. Extracts from Glioma Tissues following Cryoablation Have Proapoptosis, Antiproliferation, and Anti-Invasion Effects on Glioma Cells

    PubMed Central

    Liu, Tianzhu; Wang, Xin; Yin, Zhilin; Pan, Jun; Guo, Hongbo; Zhang, Shizhong

    2014-01-01

    Objective. This study is to investigate the in vivo apoptotic processes in glioma tissues following cryoablation and the effects of glioma tissue extracts on GL261 glioma cells in vitro. Methods. TUNEL and flow cytometry analysis were performed to detect the apoptotic processes in the glioma tissues following cryoablation and in the GL261 cells treated with cryoablated tumor extracts. The scratch assay, the transwell assay, and Western blot analysis were carried out to evaluate the effects of cryoablated tumor extracts on the migration, invasion, and proliferation of tumor cells. Results. Our in vivo results indicated that the rapid-onset apoptosis was induced via the intrinsic pathway and the delayed apoptosis was triggered through the extrinsic pathway. The in vitro results showed that extracts from glioma tissues following cryoablation induced apoptosis via extrinsic pathways in GL261 glioma cells. Furthermore, cryoablated tumor extracts significantly inhibited the migration and proliferation of these cells, which would be related to the inhibition of ERK1/2 pathway and the activation of P38 pathway. Conclusion. Glioma cells surviving in cryoablation undergo intrinsic or extrinsic apoptosis. Augmenting the induction of apoptosis or enhancing the cryosensitization of tumor cells by coupling cryoablation with specific chemotherapy effectively increases the efficiency of this therapeutic treatment. PMID:24818132

  15. Thyroid hormone transport in a human glioma cell line.

    PubMed

    Goncalves, E; Lakshmanan, M; Pontecorvi, A; Robbins, J

    1990-03-05

    The uptake of 3,5,3'-triiodothyronine (T3) and thyroxine (T4) was studied in human glioma cells (Hs 683) and compared with that in several other neural cell lines. At 25 degrees C or 37 degrees C, total cell uptake rose rapidly and reached equilibrium within 60 min. The glioma cells had the highest uptake: 47.6 fmol of L-T3 and 43.4 fmol of L-T4 per 10(6) cells at 37 degrees C. These were inhibited 77% and 72%, respectively, by excess unlabeled hormone. Uptake in the nuclei reached equilibrium between 90 and 120 min and was also highest in glioma cells: 1.46 fmol of L-T3 and 0.49 fmol of L-T4 per 10(6) cells. When expressed as percent of total cell uptake, however, glioma cells had the lowest values (3.1% for L-T3 and 1.1% for L-T4). Also in contrast to other cell lines, glioma cells transported L-T4 almost as effectively as L-T3. D-T3 and D-T4 total cell uptake was 86% and 96% lower than that of the respective L-isomers, and the nuclear uptake as a fraction of the cell uptake was similar. Kinetic analysis of the initial rate of cell uptake gave Vmax values for D-T3 and D-T4 that were 97% and 98% lower than for the L-isomers. Antimycin and monodansylcadaverine decreased the Vmax as well as the equilibrium cell and nuclear uptake of the L-isomers. The apparent nuclear affinity constant for L-T4 in intact cells was inhibited 90% in the presence of antimycin, whereas no effect was observed in isolated nuclei.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Interferon-α/β enhances temozolomide activity against MGMT-positive glioma stem-like cells.

    PubMed

    Shen, Dong; Guo, Cheng-Cheng; Wang, Jing; Qiu, Zhi-Kun; Sai, Ke; Yang, Qun-Ying; Chen, Yin-Sheng; Chen, Fu-Rong; Wang, Jie; Panasci, Lawrence; Chen, Zhong-Ping

    2015-11-01

    Glioma is one of the most common primary tumors of the central nervous system in adults. Glioblastoma (GBM) is the most lethal type of glioma, whose 5-year survival is 9.8% at best. Glioma stem-like cells (GSCs) play an important role in recurrence and treatment resistance. MGMT is a DNA repair protein that removes DNA adducts and therefore attenuates treatment efficiency. It has been reported that interferon-α/β (IFN-α/β) downregulates the level of MGMT and sensitizes glioma cells to temozolomide. In the present study, we assessed whether IFN-α/β is able to sensitize GSCs to temozolomide by modulating MGMT expression. Upon the treatment of IFN-α/β, the efficacy of temozolomide against MGMT‑positive GSCs was markedly enhanced by combination treatment with IFN-α/β when compared with the temozolomide single agent group, and MGMT expression was markedly decreased at the same time. Further mechanistic study showed that IFN-α/β suppressed the NF-κB activity, which further mediated the sensitization of MGMT‑positive GSCs to temozolomide. Our data therefore demonstrated that the application of IFN-α/β is a promising agent with which to enhance temozolomide efficiency and reduce drug resistance, and our findings shed light on improving clinical outcomes and prolonging the survival of patients with malignant gliomas.

  17. TLR9 is Critical for Glioma Stem Cell Maintenance and Targeting

    PubMed Central

    Herrmann, Andreas; Cherryholmes, Gregory; Schroeder, Anne; Phallen, Jillian; Alizadeh, Darya; Xin, Hong; Wang, Tianyi; Lee, Heehyoung; Lahtz, Christoph; Swiderski, Piotr; Armstrong, Brian; Kowolik, Claudia; Gallia, Gary L.; Lim, Michael; Brown, Christine; Badie, Behnam; Forman, Stephen; Kortylewski, Marcin; Jove, Richard; Yu, Hua

    2014-01-01

    Understanding supports for cancer stem-like cells in malignant glioma may suggest therapeutic strategies for their elimination. Here we show that the Toll-like receptor TLR9 is elevated in glioma stem-like cells (GSC) where it contributes to glioma growth. TLR9 overexpression is regulated by STAT3 which was required for GSC maintenance. Stimulation of TLR9 with a CpG ligand (CpG ODN) promoted GSC growth, whereas silencing TLR9 expression abrogated GSC development. CpG-ODN treatment induced Frizzled4-dependent activation of JAK2, thereby activating STAT3. Targeted delivery of siRNA into GSC was achieved via TLR9 using CpG-siRNA conjugates. Through local or systemic treatment, administration of CpG-Stat3 siRNA to silence STAT3 in vivo reduced GSC along with glioma growth. Our findings identify TLR9 as a functional marker for GSC and a target for the delivery of efficacious therapeutics for glioma treatment. PMID:25047528

  18. Number of glioma polyploid giant cancer cells (PGCCs) associated with vasculogenic mimicry formation and tumor grade in human glioma

    PubMed Central

    2013-01-01

    Background Polyploid giant cancer cells (PGCCs) contribute to solid tumor heterogeneity. This study investigated the relationships among PGCCs numbers, vasculogenic mimicry (VM) formation, and tumor grades in glioma. Methods A total of 76 paraffin-embedded glioma tissue samples, including 28 cases of low grade and 48 cases of high grade gliomas, were performed with H&E and immunohistochemical staining for Ki-67 and hemoglobin. The size of PGCCs nuclei was measured by a micrometer using H&E section and defined as at least three times larger than the nuclei of regular diploid cancer cells. The number of PGCCs and different blood supply patterns were compared in different grade gliomas. Microcirculation patterns in tumors were assessed using CD31 immunohistochemical and PAS histochemical double staining. Human glioma cancer cell line C6 was injected into the chicken embryonating eggs to form xenografts, which was used to observe the PGCCs and microcirculation patterns. Results In human glioma, the number of PGCCs increased with the grade of tumors (χ2 = 4.781, P = 0.015). There were three kinds of microcirculation pattern in human glioma including VM, mosaic vessel (MV) and endothelium dependent vessel. PGCCs were able to generate erythrocytes via budding to form VM. The walls of VM were positive (or negative) for PAS staining and negative for CD31 staining. There were more VM and MVs in high grade gliomas than those in low grade gliomas. The differences have statistical significances for VM (t = 3.745, P = 0.000) and MVs (t = 4.789, P = 0.000). PGCCs, VM and MVs can also be observed in C6 chicken embryonating eggs xenografts. Conclusions The data demonstrated presence of PGCCs, VM and MVs in glioma and PGCCs generating erythrocytes contribute the formation of VM and MVs. PMID:24422894

  19. A Pilot Feasibility Study of Oral 5-Fluorocytosine and Genetically-Modified Neural Stem Cells Expressing E.Coli Cytosine Deaminase for Treatment of Recurrent High Grade Gliomas

    ClinicalTrials.gov

    2015-03-02

    Adult Anaplastic Astrocytoma; Recurrent Grade III Glioma; Recurrent Grade IV Glioma; Adult Anaplastic Oligodendroglioma; Adult Brain Tumor; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Mixed Glioma; Recurrent Adult Brain Tumor; Adult Anaplastic Oligoastrocytoma; Recurrent High Grade Glioma

  20. Microscopic DTI accurately identifies early glioma cell migration: correlation with multimodal imaging in a new glioma stem cell model.

    PubMed

    Gimenez, Ulysse; Perles-Barbacaru, Adriana-T; Millet, Arnaud; Appaix, Florence; El-Atifi, Michele; Pernet-Gallay, Karin; van der Sanden, Boudewijn; Berger, François; Lahrech, Hana

    2016-11-01

    Monitoring glioma cell infiltration in the brain is critical for diagnosis and therapy. Using a new glioma Glio6 mouse model derived from human stem cells we show how diffusion tensor imaging (DTI) may predict glioma cell migration/invasion. In vivo multiparametric MRI was performed at one, two and three months of Glio6 glioma growth (Glio6 (n = 6), sham (n = 3)). This longitudinal study reveals the existence of a time window to study glioma cell/migration/invasion selectively. Indeed, at two months only Glio6 cell invasion was detected, while tumor mass formation, edema, blood-brain barrier leakage and tumor angiogenesis were detected later, at three months. To robustly confirm the potential of DTI for detecting glioma cell migration/invasion, a microscopic 3D-DTI (80 μm isotropic spatial resolution) technique was developed and applied to fixed mouse brains (Glio6 (n = 6), sham (n = 3)). DTI changes were predominant in the corpus callosum (CC), a known path of cell migration. Fractional anisotropy (FA) and perpendicular diffusivity (D⊥ ) changes derived from ex vivo microscopic 3D-DTI were significant at two months of tumor growth. In the caudate putamen an FA increase of +38% (p < 0.001) was observed, while in the CC a - 28% decrease in FA (p < 0.005) and a + 95% increase in D⊥ (p < 0.005) were observed. In the CC, DTI changes and fluorescent Glio6 cell density obtained by two-photon microscopy in the same brains were correlated (p < 0.001, r = 0.69), validating FA and D⊥ as early quantitative biomarkers to detect glioma cell migration/invasion. The origin of DTI changes was assessed by electron microscopy of the same tract, showing axon bundle disorganization. During the first two months, Glio6 cells display a migratory phenotype without being associated with the constitution of a brain tumor mass. This offers a unique opportunity to apply microscopic 3D-DTI and to validate DTI parameters FA and D⊥ as biomarkers for glioma cell

  1. [Dendritic cells and gliomas: a hope in immunotherapy?].

    PubMed

    Jouanneau, E; Poujol, D; Caux, C; Belin, M-F; Blay, J-Y; Puisieux, I

    2006-12-01

    Immunotherapy has been explored for several decades to try to improve the prognosis of gliomas, but until recently no therapeutic benefit has been achieved. The discovery of dendritic cells, the most potent professional antigen presenting cells to initiate specific immune response, and the possibility of producing them ex vivo gave rise to new protocols of active immunotherapy. In oncology, promising experimental and clinical therapeutic results were obtained using these dendritic cells loaded with tumor antigen. Patients bearing gliomas have deficit antigen presentation making this approach rational. In several experimental glioma models, independent research teams have showed specific antitumor responses using these dendritic cells. Phase I/II clinical trials have demonstrated the feasibility and the tolerance of this immunotherapeutic approach. In neuro-oncology, the efficiency of such an approach remains to be established, similarly in oncology where positive phase III studies are missing. Nevertheless, dendritic cells comprise a complex network which is only partially understood and capable of generating either immunotolerance or immune response. Numerous parameters remain to be explored before any definitive conclusion about their utility as an anticancer weapon can be drawn. It seems however logical that immunotherapy with dendritic cells could prevent or delay tumor recurrence in patients with minor active disease. A review on glioma and dendritic cells is presented.

  2. mir-300 promotes self-renewal and inhibits the differentiation of glioma stem-like cells.

    PubMed

    Zhang, Daming; Yang, Guang; Chen, Xin; Li, Chunmei; Wang, Lu; Liu, Yaohua; Han, Dayong; Liu, Huailei; Hou, Xu; Zhang, Weiguang; Li, Chenguang; Han, Zhanqiang; Gao, Xin; Zhao, Shiguang

    2014-08-01

    MicroRNAs (miRNAs) are small noncoding RNAs that have been critically implicated in several human cancers. miRNAs are thought to participate in various biological processes, including proliferation, cell cycle, apoptosis, and even the regulation of the stemness properties of cancer stem cells. In this study, we explore the potential role of miR-300 in glioma stem-like cells (GSLCs). We isolated GSLCs from glioma biopsy specimens and identified the stemness properties of the cells through neurosphere formation assays, multilineage differentiation ability analysis, and immunofluorescence analysis of glioma stem cell markers. We found that miR-300 is commonly upregulated in glioma tissues, and the expression of miR-300 was higher in GSLCs. The results of functional experiments demonstrated that miR-300 can enhance the self-renewal of GSLCs and reduce differentiation toward both astrocyte and neural fates. In addition, LZTS2 is a direct target of miR-300. In conclusion, our results demonstrate the critical role of miR-300 in GSLCs and its functions in LZTS2 inhibition and describe a new approach for the molecular regulation of tumor stem cells.

  3. Glioma Stem Cells but Not Bulk Glioma Cells Upregulate IL-6 Secretion in Microglia/Brain Macrophages via Toll-like Receptor 4 Signaling.

    PubMed

    a Dzaye, Omar Dildar; Hu, Feng; Derkow, Katja; Haage, Verena; Euskirchen, Philipp; Harms, Christoph; Lehnardt, Seija; Synowitz, Michael; Wolf, Susanne A; Kettenmann, Helmut

    2016-05-01

    Peripheral macrophages and resident microglia constitute the dominant glioma-infiltrating cells. The tumor induces an immunosuppressive and tumor-supportive phenotype in these glioma-associated microglia/brain macrophages (GAMs). A subpopulation of glioma cells acts as glioma stem cells (GSCs). We explored the interaction between GSCs and GAMs. Using CD133 as a marker of stemness, we enriched for or deprived the mouse glioma cell line GL261 of GSCs by fluorescence-activated cell sorting (FACS). Over the same period of time, 100 CD133(+ )GSCs had the capacity to form a tumor of comparable size to the ones formed by 10,000 CD133(-) GL261 cells. In IL-6(-/-) mice, only tumors formed by CD133(+ )cells were smaller compared with wild type. After stimulation of primary cultured microglia with medium from CD133-enriched GL261 glioma cells, we observed an selective upregulation in microglial IL-6 secretion dependent on Toll-like receptor (TLR) 4. Our results show that GSCs, but not the bulk glioma cells, initiate microglial IL-6 secretion via TLR4 signaling and that IL-6 regulates glioma growth by supporting GSCs. Using human glioma tissue, we could confirm the finding that GAMs are the major source of IL-6 in the tumor context.

  4. ASYMMETRIC CELL DIVISION: IMPLICATIONS FOR GLIOMA DEVELOPMENT AND TREATMENT.

    PubMed

    Lewis, Kate Marie; Petritsch, Claudia

    2013-12-01

    Glioma is a heterogeneous disease process with differential histology and treatment response. It was previously thought that the histological features of glial tumors indicated their cell of origin. However, the discovery of continuous neuro-gliogenesis in the normal adult brain and the identification of brain tumor stem cells within glioma have led to the hypothesis that these brain tumors originate from multipotent neural stem or progenitor cells, which primarily divide asymmetrically during the postnatal period. Asymmetric cell division allows these cell types to concurrently self-renew whilst also producing cells for the differentiation pathway. It has recently been shown that increased symmetrical cell division, favoring the self-renewal pathway, leads to oligodendroglioma formation from oligodendrocyte progenitor cells. In contrast, there is some evidence that asymmetric cell division maintenance in tumor stem-like cells within astrocytoma may lead to acquisition of treatment resistance. Therefore cell division mode in normal brain stem and progenitor cells may play a role in setting tumorigenic potential and the type of tumor formed. Moreover, heterogeneous tumor cell populations and their respective cell division mode may confer differential sensitivity to therapy. This review aims to shed light on the controllers of cell division mode which may be therapeutically targeted to prevent glioma formation and improve treatment response.

  5. Myosin VI contributes to malignant proliferation of human glioma cells

    PubMed Central

    Xu, Rong; Fang, Xu-hao

    2016-01-01

    Previously characterized as a backward motor, myosin VI (MYO6), which belongs to myosin family, moves toward the minus end of the actin track, a direction opposite to all other known myosin members. Recent researches have illuminated the role of MYO6 in human cancers, particularly in prostate cancer. However, the role of MYO6 in glioma has not yet been determined. In this study, to explore the role of MYO6 in human glioma, lentivirus-delivered short hairpin RNA (shRNA) targeting MYO6 was designed to stably down-regulate its endogenous expression in glioblastoma cells U251. Knockdown of MYO6 signifi cantly inhibited viability and proliferation of U251 cells in vitro. Moreover, the cell cycle of U251 cells was arrested at G0/G1 phase with the absence of MYO6, which could contribute to the suppression of cell proliferation. In conclusion, we firstly identified the crucial involvement of MYO6 in human glioma. The inhibition of MYO6 by shRNA might be a potential therapeutic method in human glioma. PMID:26937209

  6. Effect of pterostilbene on glioma cells and related mechanisms

    PubMed Central

    Yu, Liang; Zhong, Zhendong; Sun, Hongbin; Yan, Linxia; He, Baomin; Li, Supin; Ma, Shuai; Yang, Lili; Huang, Yulan

    2016-01-01

    Neuroglioma is the most common primary malignant tumor in neurosurgery. Due to unfavorable life quality of patients, the treatment of glioma is a major challenge in clinics. The search for effect treatment drugs thus benefits patient prognosis. As one derivative of resveratrol, pterostilbene has a wide spectrum of pharmaceutical functions, especially with the anti-tumor effects. This study thus investigated the effect of pterostilbene on neuroglioma and related mechanisms. U87 glioma cell line was divided into control, normal culture and different dosages of pterostilbene groups, which received 5 mM or 10 mM pterostilbene for 48 h. MTT assay was used to detect U87 cell proliferation, while invasion assay was employed to test the effect of pterostilbene on cell invasion, followed by flow cytometry assay for analyzing U87 cell apoptosis. Real-time PCR was used to test mRNA expression of Bcl-2 and Bax in glioma cells under the effect of pterostilbene, while Western blotting was used to detect alternation of Bcl-2 and Bax protein levels. Pterostilbene significantly inhibited proliferation and invasion abilities of glioma cells compared to those in control group (P<0.05). It can also enhance cell apoptosis, decrease mRNA and protein of Bcl-2 expression, and increase mRNA and protein expressions of Bax (P<0.05 compared to control group) in a dose-dependent manner. Pterostilbene can facilitate apoptosis of glioma cells, and inhibit their proliferation and invasion via mediating apoptotic/anti-apoptotic homeostasis. PMID:28077996

  7. HLF/miR-132/TTK axis regulates cell proliferation, metastasis and radiosensitivity of glioma cells.

    PubMed

    Chen, Shu; Wang, Yang; Ni, Chunxia; Meng, Ge; Sheng, Xiaofang

    2016-10-01

    Glioma is a malignant cancer with high mortality. A key prognostic factor of glioma is radiosensitivity. It has also been known that microRNAs (miR) significantly contribute to the development of glioma. miR-132 has been previously reported to inhibit tumor growth in some cancers, but not well studied in glioma. It is necessary to understand the association between miR-132 and glioma, including miR-132 expression in glioma, effects of miR-132 on cancer metastasis and radiosensitivity, and the involved molecular mechanism. We first explored the expression levels of miR-132 in human normal and glioma tissues, then correlated the expression levels with different stages of glioma. Utilizing human glioma U87 cells, lentiviral transduction technique, luciferase reporter assay, wound healing assay, transwell invasion assay and clonogenic assay, we investigated the effects of hepatic leukemia factor (HLF), miR-132 and TTK protein kinase (TTK) on cancer cell viability, proliferation, migration, invasion and radiosensitivity. The expression of miR-132 was low in human glioma tissues, and the downregulated expression was associated with advanced glioma grades. HLF directly bound to the BS1 site of miR-132 promoter to enhance the expression of miR-132. HLF-mediated miR-132 was able to directly target and inhibit a downstream factor TTK, which had an oncogenic role. Overexpression of TTK could reverse the inhibitory effects of either miR-132 or HLF on cancer cell proliferation, metastasis and radioresistance. TTK acts as an oncogene in glioma. HLF-mediated miR-132 directly suppresses TTK expression, thus exerting inhibitory effects on cancer cell proliferation, metastasis and radioresistance.

  8. Glioma-Derived ADAM10 Induces Regulatory B Cells to Suppress CD8+ T Cells

    PubMed Central

    Li, Wen-sheng; Luo, Lun; Huang, Zhen-chao; Guo, Ying

    2014-01-01

    CD8+ T cells play an important role in the anti-tumor activities of the body. The dysfunction of CD8+ T cells in glioma is unclear. This study aims to elucidate the glioma cell-derived ADAM10 (A Disintegrin and metalloproteinase domain-containing protein 10) in the suppression of CD8+ effector T cells by the induction of regulatory B cells. In this study, glioma cells were isolated from surgically removed glioma tissue and stimulated by Phorbol myristate acetage (PMA) in the culture. The levels of ADAM10 in the culture were determined by enzyme-linked immunosorbent assay. Immune cells were assessed by flow cytometry. The results showed that the isolated glioma cells express ADAM10, which was markedly up regulated after stimulated with PMA. The glioma-derived ADAM10 induced activated B cells to differentiate into regulatory B cells, the later suppressed CD8+ T cell proliferation as well as the induced regulatory T cells, which also showed the immune suppressor effect on CD8+ effector T cell proliferation. In conclusion, glioma cells produce ADAM10 to induce Bregs; the latter suppresses CD8+ T cells and induces Tregs. PMID:25127032

  9. Integrin inhibition promotes atypical anoikis in glioma cells

    PubMed Central

    Silginer, M; Weller, M; Ziegler, U; Roth, P

    2014-01-01

    Integrins regulate cellular adhesion and transmit signals important for cell survival, proliferation and motility. They are expressed by glioma cells and may contribute to their malignant phenotype. Integrin inhibition may therefore represent a promising therapeutic strategy. GL-261 and SMA-560 glioma cells grown under standard conditions uniformly detached and formed large cell clusters after integrin gene silencing or pharmacological inhibition using EMD-121974, a synthetic Arg-Gly-Asp-motif peptide, or GLPG0187, a nonpeptidic integrin inhibitor. After 120 h, the clusters induced by integrin inhibition decayed and cells died. In contrast, when cells were cultured under stem cell (sphere) conditions, no disaggregation became apparent upon integrin inhibition, and cell death was not observed. As poly-HEMA-mediated detachment had similar effects on cell viability as integrin inhibition, we postulated that cell death may result from detachment alone, which was confirmed using various permissive and nonpermissive substrates. No surrogate markers of apoptosis were detected and electron microscopy confirmed that necrosis represents the dominant morphology of detachment-induced cell death. In addition, integrin inhibition resulted in the induction of autophagy that represents a survival signal. When integrins were inhibited in nonsphere glioma cells, the TGF-β pathway was strongly impaired, whereas no such effect was observed in glioma cells cultured under sphere conditions. Cell death induced by integrin inhibition was rescued by the addition of recombinant transforming growth factor-β (TGF-β) and accelerated by exposure to the TGF-β receptor inhibitor, SD-208. In summary, cell death following integrin inhibition is detachment mediated, represents an atypical form of anoikis involving necrosis as well as autophagy, and is modulated by TGF-β pathway activity. PMID:24457956

  10. Differential response of glioma cells to FOXO1-directed therapy.

    PubMed

    Lau, Cara J; Koty, Zaf; Nalbantoglu, Josephine

    2009-07-01

    Gliomas are the most common adult primary brain tumors, and the most malignant form, glioblastoma multiforme, is invariably fatal. The phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway is altered in most glioblastoma multiforme. PTEN, an important negative regulator of the PI3K-Akt pathway, is also commonly mutated in glioma, leading to constitutive activation of Akt. One ultimate consequence is phosphorylation and inactivation of FOXO forkhead transcription factors that regulate genes involved in apoptosis, cell cycle arrest, nutrient availability, DNA repair, stress, and angiogenesis. We tested the ability of a mutant FOXO1 factor that is not subject to Akt phosphorylation to overcome dysregulated PI3K-Akt signaling in two PTEN-null glioma cell lines, U87 and U251. Adenovirus-mediated gene transfer of the mutant FOXO1 successfully restored cell cycle arrest and induced cell death in vitro and prolonged survival in vivo in xenograft models of human glioma (33% survival at 1 year of animals bearing U251 tumors). However, U87 were much more resistant than U251 to mutant FOXO1-induced death, showing evidence of increased nuclear export and Akt-independent phosphorylation of FOXO1 at S249. A cyclin-dependent kinase 2 inhibitor decreased phosphorylation of S249 and rendered U87 cells significantly more susceptible to mutant FOXO1-induced death. Our results indicate that targeting FOXO1, which is at the convergence point of several growth factor receptor tyrosine kinase pathways, can effectively induce glioma cell death and inhibit tumor growth. They also highlight the importance of Akt-independent phosphorylation events in the nuclear export of FOXO1.

  11. The chemokine receptor CXCR7 is highly expressed in human glioma cells and mediates antiapoptotic effects.

    PubMed

    Hattermann, Kirsten; Held-Feindt, Janka; Lucius, Ralph; Müerköster, Susanne Sebens; Penfold, Mark E T; Schall, Thomas J; Mentlein, Rolf

    2010-04-15

    The chemokine CXCL12/stromal cell-derived factor-1 and its receptor CXCR4 play a major role in tumor invasion, proliferation, and metastasis. Recently, CXCR7 was identified as a novel, alternate receptor for CXCL12 and CXCL11/I-TAC. Because both chemokines are expressed abundantly in human astrocytomas and glioblastomas, we investigated the occurrence and function of both receptors in astroglial tumors. In situ, CXCR7 is highly expressed on tumor endothelial, microglial, and glioma cells whereas CXCR4 has a much more restricted localization; CXCL12 is often colocalized with CXCR7. CXCR7 transcription in tumor homogenates increased with malignancy. In vitro, CXCR7 was highly expressed in all glioma cell lines investigated whereas CXCR4 was only scarcely transcribed on one of eight lines. In contrast, a tumor stem-like cell line preferentially expressed CXCR4 which diminished upon differentiation, whereas CXCR7 increased drastically. Stimulation of CXCR7-positive glioma cells (CXCR4- and CXCR3-negative) by CXCL12 induced transient phosphorylation of extracellular signal-regulated kinases Erk1/2, indicating that the receptor is functionally active. The phosphoinositide-specific phospholipase C inhibitor U73122 effectively inhibited Erk activation and suggests that the mitogen-activated protein kinase pathway is activated indirectly. Whereas proliferation and migration were little influenced, chemokine stimulation prevented camptothecin- and temozolomide-induced apoptosis. The selective CXCR7 antagonist CCX733 reduced the antiapoptotic effects of CXCL12 as shown by nuclear (Nicoletti) staining, caspase-3/7 activity assays, and cleavage of poly(ADP-ribose) polymerase-1. Thus, CXCR7 is a functional receptor for CXCL12 in astrocytomas/glioblastomas and mediates resistance to drug-induced apoptosis. Whereas CXCR7 is found on "differentiated" glioma cells, the alternate receptor CXCR4 is also localized on glioma stem-like cells.

  12. Compound K attenuates stromal cell-derived growth factor 1 (SDF-1)-induced migration of C6 glioma cells

    PubMed Central

    Kim, Hyuck; Roh, Hyo Sun; Kim, Jai Eun; Park, Sun Dong; Park, Won Hwan

    2016-01-01

    BACKGROUND/OBJECTIVES Stromal cell-derived growth factor 1 (SDF-1), also known as chemokine ligand 12, and chemokine receptor type 4 are involved in cancer cell migration. Compound K (CK), a metabolite of protopanaxadiol-type ginsenoside by gut microbiota, is reported to have therapeutic potential in cancer therapy. However, the inhibitory effect of CK on SDF-1 pathway-induced migration of glioma has not yet been established. MATERIALS/METHODS Cytotoxicity of CK in C6 glioma cells was determined using an EZ-Cytox cell viability assay kit. Cell migration was tested using the wound healing and Boyden chamber assay. Phosphorylation levels of protein kinase C (PKC)α and extracellular signal-regulated kinase (ERK) were measured by western blot assay, and matrix metallopeptidases (MMP) were measured by gelatin-zymography analysis. RESULTS CK significantly reduced the phosphorylation of PKCα and ERK1/2, expression of MMP9 and MMP2, and inhibited the migration of C6 glioma cells under SDF-1-stimulated conditions. CONCLUSIONS CK is a cell migration inhibitor that inhibits C6 glioma cell migration by regulating its downstream signaling molecules including PKCα, ERK1/2, and MMPs. PMID:27247721

  13. Selective calcium sensitivity in immature glioma cancer stem cells.

    PubMed

    Wee, Shimei; Niklasson, Maria; Marinescu, Voichita Dana; Segerman, Anna; Schmidt, Linnéa; Hermansson, Annika; Dirks, Peter; Forsberg-Nilsson, Karin; Westermark, Bengt; Uhrbom, Lene; Linnarsson, Sten; Nelander, Sven; Andäng, Michael

    2014-01-01

    Tumor-initiating cells are a subpopulation in aggressive cancers that exhibit traits shared with stem cells, including the ability to self-renew and differentiate, commonly referred to as stemness. In addition, such cells are resistant to chemo- and radiation therapy posing a therapeutic challenge. To uncover stemness-associated functions in glioma-initiating cells (GICs), transcriptome profiles were compared to neural stem cells (NSCs) and gene ontology analysis identified an enrichment of Ca2+ signaling genes in NSCs and the more stem-like (NSC-proximal) GICs. Functional analysis in a set of different GIC lines regarding sensitivity to disturbed homeostasis using A23187 and Thapsigargin, revealed that NSC-proximal GICs were more sensitive, corroborating the transcriptome data. Furthermore, Ca2+ drug sensitivity was reduced in GICs after differentiation, with most potent effect in the NSC-proximal GIC, supporting a stemness-associated Ca2+ sensitivity. NSCs and the NSC-proximal GIC line expressed a larger number of ion channels permeable to potassium, sodium and Ca2+. Conversely, a higher number of and higher expression levels of Ca2+ binding genes that may buffer Ca2+, were expressed in NSC-distal GICs. In particular, expression of the AMPA glutamate receptor subunit GRIA1, was found to associate with Ca2+ sensitive NSC-proximal GICs, and decreased as GICs differentiated along with reduced Ca2+ drug sensitivity. The correlation between high expression of Ca2+ channels (such as GRIA1) and sensitivity to Ca2+ drugs was confirmed in an additional nine novel GIC lines. Calcium drug sensitivity also correlated with expression of the NSC markers nestin (NES) and FABP7 (BLBP, brain lipid-binding protein) in this extended analysis. In summary, NSC-associated NES+/FABP7+/GRIA1+ GICs were selectively sensitive to disturbances in Ca2+ homeostasis, providing a potential target mechanism for eradication of an immature population of malignant cells.

  14. Fluid Shear Stress Regulates the Invasive Potential of Glioma Cells via Modulation of Migratory Activity and Matrix Metalloproteinase Expression

    PubMed Central

    Qazi, Henry; Shi, Zhong-Dong; Tarbell, John M.

    2011-01-01

    Background Glioma cells are exposed to elevated interstitial fluid flow during the onset of angiogenesis, at the tumor periphery while invading normal parenchyma, within white matter tracts, and during vascular normalization therapy. Glioma cell lines that have been exposed to fluid flow forces in vivo have much lower invasive potentials than in vitro cell motility assays without flow would indicate. Methodology/Principal Findings A 3D Modified Boyden chamber (Darcy flow through collagen/cell suspension) model was designed to mimic the fluid dynamic microenvironment to study the effects of fluid shear stress on the migratory activity of glioma cells. Novel methods for gel compaction and isolation of chemotactic migration from flow stimulation were utilized for three glioma cell lines: U87, CNS-1, and U251. All physiologic levels of fluid shear stress suppressed the migratory activity of U87 and CNS-1 cell lines. U251 motility remained unaltered within the 3D interstitial flow model. Matrix Metalloproteinase (MMP) inhibition experiments and assays demonstrated that the glioma cells depended on MMP activity to invade, and suppression in motility correlated with downregulation of MMP-1 and MMP-2 levels. This was confirmed by RT-PCR and with the aid of MMP-1 and MMP-2 shRNA constructs. Conclusions/Significance Fluid shear stress in the tumor microenvironment may explain reduced glioma invasion through modulation of cell motility and MMP levels. The flow-induced migration trends were consistent with reported invasive potentials of implanted gliomas. The models developed for this study imply that flow-modulated motility involves mechanotransduction of fluid shear stress affecting MMP activation and expression. These models should be useful for the continued study of interstitial flow effects on processes that affect tumor progression. PMID:21637818

  15. Novel cancer-testis antigen expression on glioma cell lines derived from high-grade glioma patients.

    PubMed

    Akiyama, Yasuto; Komiyama, Masaru; Miyata, Haruo; Yagoto, Mika; Ashizawa, Tadashi; Iizuka, Akira; Oshita, Chie; Kume, Akiko; Nogami, Masahiro; Ito, Ichiro; Watanabe, Reiko; Sugino, Takashi; Mitsuya, Koichi; Hayashi, Nakamasa; Nakasu, Yoko; Yamaguchi, Ken

    2014-04-01

    Glioblastoma multiforme (GBM) is one of the most malignant and aggressive tumors, and has a very poor prognosis with a mean survival time of <2 years, despite intensive treatment using chemo-radiation. Therefore, novel therapeutic approaches including immunotherapy have been developed against GBM. For the purpose of identifying novel target antigens contributing to GBM treatment, we developed 17 primary glioma cell lines derived from high-grade glioma patients, and analyzed the expression of various tumor antigens and glioma-associated markers using a quantitative PCR and immunohistochemistry (IHC). A quantitative PCR using 54 cancer-testis (CT) antigen-specific primers showed that 36 CT antigens were positive in at least 1 of 17 serum-derived cell lines, and 17 antigens were positive in >50% cell lines. Impressively, 6 genes (BAGE, MAGE-A12, CASC5, CTAGE1, DDX43 and IL-13RA2) were detected in all cell lines. The expression of other 13 glioma-associated antigens than CT genes were also investigated, and 10 genes were detected in >70% cell lines. The expression of CT antigen and glioma-associated antigen genes with a high frequency were also verified in IHC analysis. Moreover, a relationship of antigen gene expressions with a high frequency to overall survival was investigated using the Repository of Molecular Brain Neoplasia Data (REMBRANDT) database of the National Cancer Institute, and expression of 6 genes including IL-13RA2 was inversely correlated to overall survival time. Furthermore, 4 genes including DDX43, TDRD1, HER2 and gp100 were identified as MGMT-relevant factors. In the present study, several CT antigen including novel genes were detected in high-grade glioma primary cell lines, which might contribute to developing novel immunotherapy and glioma-specific biomarkers in future.

  16. Molecular dissection of the valproic acid effects on glioma cells

    PubMed Central

    Hoja, Sabine; Schulze, Markus; Rehli, Michael; Proescholdt, Martin; Herold-Mende, Christel; Hau, Peter; Riemenschneider, Markus J.

    2016-01-01

    Many glioblastoma patients suffer from seizures why they are treated with antiepileptic agents. Valproic acid (VPA) is a histone deacetylase inhibitor that apart from its anticonvulsive effects in some retrospective studies has been suggested to lead to a superior outcome of glioblastoma patients. However, the exact molecular effects of VPA treatment on glioblastoma cells have not yet been deciphered. We treated glioblastoma cells with VPA, recorded the functional effects of this treatment and performed a global and unbiased next generation sequencing study on the chromatin (ChIP) and RNA level. 1) VPA treatment clearly sensitized glioma cells to temozolomide: A protruding VPA-induced molecular feature in this context was the transcriptional upregulation/reexpression of numerous solute carrier (SLC) transporters that was also reflected by euchromatinization on the histone level and a reexpression of SLC transporters in human biopsy samples after VPA treatment. DNA repair genes were adversely reduced. 2) VPA treatment, however, also reduced cell proliferation in temozolomide-naive cells: On the molecular level in this context we observed a transcriptional upregulation/reexpression and euchromatinization of several glioblastoma relevant tumor suppressor genes and a reduction of stemness markers, while transcriptional subtype classification (mesenchymal/proneural) remained unaltered. Taken together, these findings argue for both temozolomide-dependent and -independent effects of VPA. VPA might increase the uptake of temozolomide and simultaneously lead to a less malignant glioblastoma phenotype. From a mere molecular perspective these findings might indicate a surplus value of VPA in glioblastoma therapy and could therefore contribute an additional ratio for clinical decision making. PMID:27556305

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

    PubMed Central

    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

  18. Relationship between extracellular osmolarity, NaCl concentration and cell volume in rat glioma cells.

    PubMed

    Rouzaire-Dubois, Béatrice; Ouanounou, Gilles; Dubois, Jean Marc

    2011-06-01

    The cell volume, which controls numerous cellular functions, is theoretically linearly related with the inverse osmolarity. However, deviations from this law have often been observed. In order to clarify the origin of these deviations we electronically measured the mean cell volume of rat glioma cells under three different experimental conditions, namely: at different osmolarities and constant NaCl concentration; at different NaCl concentrations and constant osmolarity and at different osmolarities caused by changes in NaCl concentration. In each condition, the osmolarity was maintained constant or changed with NaCl or mannitol. We showed that the cell volume was dependent on both the extracellular osmolarity and the NaCl concentration. The relationship between cell volume, osmolarity and NaCl concentration could be described by a new equation that is the product of the Boyle-van't Hoff law and the Michaelis-Menten equation at a power of 4. Together, these results suggest that in hyponatriemia, the cell volume deviates from the Boyle-van't Hoff law because either the activity of aquaporin 1, expressed in glioma cells, is decreased or the reduced NaCl influx decreases the osmotically obliged influx of water.

  19. Knockdown of long non-coding RNA HOTAIR inhibits malignant biological behaviors of human glioma cells via modulation of miR-326

    PubMed Central

    Ke, Jing; Yao, Yi-long; Zheng, Jian; Wang, Ping; Liu, Yun-hui; Ma, Jun; Li, Zhen; Liu, Xiao-bai; Li, Zhi-qing; Wang, Zhen-hua; Xue, Yi-xue

    2015-01-01

    Glioma is the most common and aggressive primary adult brain tumor. Long non-coding RNAs (lncRNAs) have important roles in a variety of biological properties of cancers. Here, we elucidated the function and the possible molecular mechanisms of lncRNA HOTAIR in human glioma U87 and U251 cell lines. Quantitative RT-PCR demonstrated that HOTAIR expression was up-regulated in glioma tissues and cell lines. Knockdown of HOTAIR exerted tumor-suppressive function in glioma cells. Further, HOTAIR was confirmed to be the target of miR-326 and miR-326 mediated the tumor-suppressive effects of HOTAIR knockdown on glioma cell lines. Moreover, over-expressed miR-326 reduced the FGF1 expression which played an oncogenic role in glioma by activating PI3K/AKT and MEK 1/2 pathways. In addition, the in vivo studies also supported the above findings. Taken together, knockdown of HOTAIR up-regulated miR-326 expression, and further inducing the decreased expression of FGF1, these results provided a comprehensive analysis of HOTAIR-miR-326-FGF1 axis in human glioma and provided a new potential therapeutic strategy for glioma treatment. PMID:26183397

  20. DNA fingerprinting of glioma cell lines and considerations on similarity measurements.

    PubMed

    Bady, Pierre; Diserens, Annie-Claire; Castella, Vincent; Kalt, Stefanie; Heinimann, Karl; Hamou, Marie-France; Delorenzi, Mauro; Hegi, Monika E

    2012-06-01

    Glioma cell lines are an important tool for research in basic and translational neuro-oncology. Documentation of their genetic identity has become a requirement for scientific journals and grant applications to exclude cross-contamination and misidentification that lead to misinterpretation of results. Here, we report the standard 16 marker short tandem repeat (STR) DNA fingerprints for a panel of 39 widely used glioma cell lines as reference. Comparison of the fingerprints among themselves and with the large DSMZ database comprising 9 marker STRs for 2278 cell lines uncovered 3 misidentified cell lines and confirmed previously known cross-contaminations. Furthermore, 2 glioma cell lines exhibited identity scores of 0.8, which is proposed as the cutoff for detecting cross-contamination. Additional characteristics, comprising lack of a B-raf mutation in one line and a similarity score of 1 with the original tumor tissue in the other, excluded a cross-contamination. Subsequent simulation procedures suggested that, when using DNA fingerprints comprising only 9 STR markers, the commonly used similarity score of 0.8 is not sufficiently stringent to unambiguously differentiate the origin. DNA fingerprints are confounded by frequent genetic alterations in cancer cell lines, particularly loss of heterozygosity, that reduce the informativeness of STR markers and, thereby, the overall power for distinction. The similarity score depends on the number of markers measured; thus, more markers or additional cell line characteristics, such as information on specific mutations, may be necessary to clarify the origin.

  1. Investigation of adhesion and mechanical properties of human glioma cells by single cell force spectroscopy and atomic force microscopy.

    PubMed

    Andolfi, Laura; Bourkoula, Eugenia; Migliorini, Elisa; Palma, Anita; Pucer, Anja; Skrap, Miran; Scoles, Giacinto; Beltrami, Antonio Paolo; Cesselli, Daniela; Lazzarino, Marco

    2014-01-01

    Active cell migration and invasion is a peculiar feature of glioma that makes this tumor able to rapidly infiltrate into the surrounding brain tissue. In our recent work, we identified a novel class of glioma-associated-stem cells (defined as GASC for high-grade glioma--HG--and Gasc for low-grade glioma--LG) that, although not tumorigenic, act supporting the biological aggressiveness of glioma-initiating stem cells (defined as GSC for HG and Gsc for LG) favoring also their motility. Migrating cancer cells undergo considerable molecular and cellular changes by remodeling their cytoskeleton and cell interactions with surrounding environment. To get a better understanding about the role of the glioma-associated-stem cells in tumor progression, cell deformability and interactions between glioma-initiating stem cells and glioma-associated-stem cells were investigated. Adhesion of HG/LG-cancer cells on HG/LG-glioma-associated stem cells was studied by time-lapse microscopy, while cell deformability and cell-cell adhesion strengths were quantified by indentation measurements by atomic force microscopy and single cell force spectroscopy. Our results demonstrate that for both HG and LG glioma, cancer-initiating-stem cells are softer than glioma-associated-stem cells, in agreement with their neoplastic features. The adhesion strength of GSC on GASC appears to be significantly lower than that observed for Gsc on Gasc. Whereas, GSC spread and firmly adhere on Gasc with an adhesion strength increased as compared to that obtained on GASC. These findings highlight that the grade of glioma-associated-stem cells plays an important role in modulating cancer cell adhesion, which could affect glioma cell migration, invasion and thus cancer aggressiveness. Moreover this work provides evidence about the importance of investigating cell adhesion and elasticity for new developments in disease diagnostics and therapeutics.

  2. Investigation of Adhesion and Mechanical Properties of Human Glioma Cells by Single Cell Force Spectroscopy and Atomic Force Microscopy

    PubMed Central

    Andolfi, Laura; Bourkoula, Eugenia; Migliorini, Elisa; Palma, Anita; Pucer, Anja; Skrap, Miran; Scoles, Giacinto; Beltrami, Antonio Paolo; Cesselli, Daniela; Lazzarino, Marco

    2014-01-01

    Active cell migration and invasion is a peculiar feature of glioma that makes this tumor able to rapidly infiltrate into the surrounding brain tissue. In our recent work, we identified a novel class of glioma-associated-stem cells (defined as GASC for high-grade glioma -HG- and Gasc for low-grade glioma -LG-) that, although not tumorigenic, act supporting the biological aggressiveness of glioma-initiating stem cells (defined as GSC for HG and Gsc for LG) favoring also their motility. Migrating cancer cells undergo considerable molecular and cellular changes by remodeling their cytoskeleton and cell interactions with surrounding environment. To get a better understanding about the role of the glioma-associated-stem cells in tumor progression, cell deformability and interactions between glioma-initiating stem cells and glioma-associated-stem cells were investigated. Adhesion of HG/LG-cancer cells on HG/LG-glioma-associated stem cells was studied by time-lapse microscopy, while cell deformability and cell-cell adhesion strengths were quantified by indentation measurements by atomic force microscopy and single cell force spectroscopy. Our results demonstrate that for both HG and LG glioma, cancer-initiating-stem cells are softer than glioma-associated-stem cells, in agreement with their neoplastic features. The adhesion strength of GSC on GASC appears to be significantly lower than that observed for Gsc on Gasc. Whereas, GSC spread and firmly adhere on Gasc with an adhesion strength increased as compared to that obtained on GASC. These findings highlight that the grade of glioma-associated-stem cells plays an important role in modulating cancer cell adhesion, which could affect glioma cell migration, invasion and thus cancer aggressiveness. Moreover this work provides evidence about the importance of investigating cell adhesion and elasticity for new developments in disease diagnostics and therapeutics. PMID:25390644

  3. Evidence from a large-scale meta-analysis indicates eczema reduces the incidence of glioma

    PubMed Central

    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

  4. The effects of CD147 on the cell proliferation, apoptosis, invasion, and angiogenesis in glioma.

    PubMed

    Yin, Haoyuan; Shao, Ying; Chen, Xuan

    2017-01-01

    To analyze the effects of extracellular matrix metalloproteinase inducer (CD147) on glioma proliferation, apoptosis, invasion, and angiogenesis. Tissue samples were obtained from 101 glioma cases while normal brain tissues were obtained from 30 brain injury cases. Immunohistochemical assay was performed to detect the expressions of CD147, CD34, and VEGF in tissue samples. QRT-PCR was performed to detect the relative expression of CD147 mRNA in human glioma cell lines. CD147 siRNA was transfected into glioma cell line U251. Cell proliferation, apoptosis, invasion, and angiogenesis were tested by MTT, flow cytometry, Transwell assay, and vasculogenic mimicry assay, respectively. Expressions of relative proteins were analyzed with western blot. CD147 was positively expressed with the percentage of 0, 37.5, 44.8, 67.9, and 85.7 % in normal tissues and glioma tissues with WHO grades I-IV, respectively, and the scores of MVDand VEGF were associated with the expression of CD147. CD147 was significantly upregulated in the human glioma cell lines (P < 0.05). Downregulated the expression of CD147 suppressed cell proliferation, blocked cell cycle, induced apoptosis, inhibited cell invasion and angiogenesis in glioma cells in vitro. The expression of CD147 was significantly associated with WHO tumor grade and angiogenesis; silencing of CD147 contributed to inhibition of glioma proliferation, invasion, and angiogenesis. Our study provided firm evidence that CD 147 is a potential glioma target for anti-angiogenic therapies.

  5. The effect of yacon (Samallanthus sonchifolius) ethanol extract on cell proliferation and migration of C6 glioma cells stimulated with fetal bovine serum

    PubMed Central

    Lee, Kang Pa; Choi, Nan Hee; Kim, Jin Teak

    2015-01-01

    BACKGROUND/OBJECTIVES Yacon (Samallanthus sonchifolius), a common edible plant grown throughout the world, is well known for its antidiabetic properties. It is also known to have several other pharmacological properties including anti-inflammatory, anti-oxidant, anti-allergic, and anti-cancer effects. To date, the effect of yacon on gliomas has not been studied. In this study, we investigated the effects of yacon on the migration and proliferation of C6 glioma cells stimulated by fetal bovine serum (FBS). MATERIALS/METHODS Cell growth and proliferation were determined by evaluating cell viability using an EZ-Cytox Cell Viability Assay Kit. FBS-induced migration of C6 glioma cells was evaluated by performing the scratch wound healing assay and the Boyden chamber assay. We also used western blot analysis to determine the expression levels of extracellular signal-regulated kinase 1/2 (ERK1/2), a major regulator of migration and proliferation of glioma cells. Matrix metallopeptidase (MMP) 9 and TIMP-1 levels were measured by performing reverse transcription PCR. RESULTS Yacon (300 µg/mL) reduced both the FBS-induced proliferation of C6 glioma cells and the dose-dependent migration of the FBS-stimulated C6 cells. FBS-stimulated C6 glioma cells treated with yacon (200 and 300 µg/mL) showed reduced phosphorylation of ERK1/2 and inhibition of MMP 9 expression compared to those shown by the untreated FBS-stimulated C6 cells. In contrast, yacon (200 and 300 µg/mL) induced TIMP-1 expression. CONCLUSIONS On the basis of these results, we suggest that yacon may exert an anti-cancer effect on FBS-stimulated C6 glioma cells by inhibiting their proliferation and migration. The most likely mechanism for this is down-regulation of ERK1/2 and MMP9 and up-regulation of TIMP-1 expression levels. PMID:26060537

  6. Aloe-emodin modulates PKC isozymes, inhibits proliferation, and induces apoptosis in U-373MG glioma cells.

    PubMed

    Acevedo-Duncan, Mildred; Russell, Christopher; Patel, Sapna; Patel, Rekha

    2004-12-20

    Aloe-emodin (1,8-dihydroy-3-[hydroxymethyl]-anthraquione) purified from Aloe vera leaves has been reported to have antitumor activity. The objectives of our research were to determine how aloe-emodin regulates the cell cycle, cell proliferation and protein kinase C (PKC) during glioma growth and development. To establish the cell cycle effects of aloe-emodin on brain cells [transformed glia cell line (SVG) and human glioma U-373MG cell line (U-373MG)], cells were treated with either dimethylsulfoxide (DMSO; control) or aloe-emodin (40 microM). Results from flow cytometry demonstrated that aloe-emodin delayed the number of cells entering and exiting DNA synthesis (S) phase in both SVG and U-373MG cells indicating that aloe-emodin may inhibit S phase progression. Assessment of cell viability demonstrated that SVG and U-373MG glioma cell were highly sensitive to aloe-emodin. The aloe-emodin-induced decreased proliferation was sustained at 48-96 h. A PKC activity assay was quantified to establish the role of PKC in aloe-emodin's mode of action. Exposure of SVG and U-373MG glioma cells to aloe-emodin suppressed PKC activity and reduced the protein content of most of the PKC isozymes. We determined that cancer growth inhibition by aloe-emodin was due to apoptosis (i.e., programmed cell death). Taken together, these results support the hypothesis that aloe-emodin represents a novel antitumor chemotherapeutic drug.

  7. LuIII parvovirus selectively and efficiently targets, replicates in, and kills human glioma cells.

    PubMed

    Paglino, Justin C; Ozduman, Koray; van den Pol, Anthony N

    2012-07-01

    Because productive infection by parvoviruses requires cell division and is enhanced by oncogenic transformation, some parvoviruses may have potential utility in killing cancer cells. To identify the parvovirus(es) with the optimal oncolytic effect against human glioblastomas, we screened 12 parvoviruses at a high multiplicity of infection (MOI). MVMi, MVMc, MVM-G17, tumor virus X (TVX), canine parvovirus (CPV), porcine parvovirus (PPV), rat parvovirus 1A (RPV1A), and H-3 were relatively ineffective. The four viruses with the greatest oncolytic activity, LuIII, H-1, MVMp, and MVM-G52, were tested for the ability, at a low MOI, to progressively infect the culture over time, causing cell death at a rate higher than that of cell proliferation. LuIII alone was effective in all five human glioblastomas tested. H-1 progressively infected only two of five; MVMp and MVM-G52 were ineffective in all five. To investigate the underlying mechanism of LuIII's phenotype, we used recombinant parvoviruses with the LuIII capsid replacing the MVMp capsid or with molecular alteration of the P4 promoter. The LuIII capsid enhanced efficient replication and oncolysis in MO59J gliomas cells; other gliomas tested required the entire LuIII genome to exhibit enhanced infection. LuIII selectively infected glioma cells over normal glial cells in vitro. In mouse models, human glioblastoma xenografts were selectively infected by LuIII when administered intratumorally; LuIII reduced tumor growth by 75%. LuIII also had the capacity to selectively infect subcutaneous or intracranial gliomas after intravenous inoculation. Intravenous or intracranial LuIII caused no adverse effects. Intracranial LuIII caused no infection of mature mouse neurons or glia in vivo but showed a modest infection of developing neurons.

  8. Gefitinib induces apoptosis in human glioma cells by targeting Bad phosphorylation.

    PubMed

    Chang, Cheng-Yi; Shen, Chiung-Chyi; Su, Hong-Lin; Chen, Chun-Jung

    2011-12-01

    Gefitinib, a selective epidermal growth factor receptor tyrosine kinase inhibitor, is under clinical testing and use in cancer patients, including glioma. However, the molecular mechanisms involved in gefitinib-mediated anticancer effects against glioma remain largely uncharacterized. Gefitinib inhibits cell growth and induces apoptosis in human glioma cells. Gefitinib also induces death of H4 cells with characteristics of the intrinsic apoptotic pathway, including Bax mitochondrial translocation, mitochondrial outer membrane permeabilization, cytochrome c cytosolic release, and caspase-9/caspase-3 activation. The importance of Bax in mediating gefitinib-induced apoptosis was confirmed by the attenuation of apoptosis by Bax siRNA and Bax channel blocker. Gefitinib caused Bad dephosphorylation, particularly in serine-112, and increased its binding preference to Bcl-2 and Bcl-xL. The dephosphorylation of Bad in gefitinib-treated cells was accompanied by reduced intracellular cyclic AMP content and protein kinase A (PKA) activity. Adenylyl cyclase activator forskolin attenuated, but PKA inhibitor H89 augmented, gefitinib-induced Bad dephosphorylation, Bax mitochondrial translocation, caspase-9/caspase-3 activation, and viability loss. Intriguingly, a nonselective protein phosphatase inhibitor okadaic acid alleviated gefitinib-induced alterations, except Bad dephosphorylation. In parallel with the higher basal PKA activity, response of U87 cells to gefitinib treatment was delayed and relatively resistant compared with that of H4 and T98G cells. Inactivation of PKA sensitized H4, T98G, and U87 cells to gefitinib cytotoxicity, Bad dephosphorylation in serine-112, and caspase-9/caspase-3 activation. Our findings suggest the involvement of the Bad/Bax signaling pathway in gefitinib-induced glioma apoptosis. Furthermore, the inactivation of PKA was shown to play a role in triggering the proapoptotic function of Bad.

  9. MicroRNA-218 modulates activities of glioma cells by targeting HMGB1

    PubMed Central

    Gu, Jianjun; Xu, Rong; Li, Yaxing; Zhang, Jianhe; Wang, Shousen

    2016-01-01

    To explore the effects of microRNA-218 (miR-218) on glioma cell lines and the related mechanism. U251 and U87 cells were transfected with negative control, miR-218 mimic or miR-218 inhibitor using lipofectamine 2000. The expressions of mRNA and proteins were detected with qRT-PCR and Western blotting. The cell proliferation, apoptosis, migration and invasion were studied using MTT, flow cytometry, Transwell assay and scratch-wound assay, respectively. The targeting effect of HMGB1 by miR-218 was measured with luciferase reporter assay. The results showed that miR-218 was significantly downregulated while HMGB1 was upregulated in both glioma cell lines. Transfection of miR-218 significantly reduced the cell viability and colony formation, increased cell apoptosis and arrested cell in G0/G1 phase. Transfection of miR-218 also decreased the invasion and migration of glioma cells. The expressions of HMGB1, RAGE, cyclin D1 and MMP-9 were downregulated while the expression of caspase-9 was upregulated by miR-218. Silencing HMGB1 increased the expression of RAGE, cyclin D1, MMP-9 but decreased the expression of caspase-9 in U251 and U87 cells. Co-transfection with pcHMGB1 and miR-218 significantly decreased the growth inhibition and increased the apoptosis of glioma cells while these effects were abolished in glioma cells co-transfected with HMGB1 siRNA and miR-218 inhibitor. In addition, co-transfection with pcHMGB1 and miR-218 inhibitor increased the invasiveness of U251 and U87 cells. These findings suggested that miR-218 may negatively regulate HMGB-mediated suppression of RAGE to regulate cell proliferation, apoptosis and invasion, and that intervention of miR-218-HMGB1-RAGE may be useful for developing potential clinical strategies. PMID:27725858

  10. The Effect of Temozolomide/Poly(lactide-co-glycolide) (PLGA)/Nano-Hydroxyapatite Microspheres on Glioma U87 Cells Behavior

    PubMed Central

    Zhang, Dongyong; Tian, Ang; Xue, Xiangxin; Wang, Mei; Qiu, Bo; Wu, Anhua

    2012-01-01

    In this study, we investigated the effects of temozolomide (TMZ)/Poly (lactide-co-glycolide)(PLGA)/nano-hydroxyapatite microspheres on the behavior of U87 glioma cells. The microspheres were fabricated by the “Solid/Water/Oil” method, and they were characterized by using X-Ray diffraction, scanning electron microscopy and differential scanning calorimetry. The proliferation, apoptosis and invasion of glioma cells were evaluated by MTT, flow cytometry assay and Transwell assay. The presence of the key invasive gene, αVβ3 integrin, was detected by the RT-PCR and Western blot method. It was found that the temozolomide/PLGA/nano-hydroxyapatite microspheres have a significantly diminished initial burst of drug release, compared to the TMZ laden PLGA microspheres. Our results suggest they can significantly inhibit the proliferation and invasion of glioma cells, and induce their apoptosis. Additionally, αVβ3 integrin was also reduced by the microspheres. These data suggest that by inhibiting the biological behavior of glioma cells in vitro, the newly designed temozolomide/PLGA/nano-hydroxyapatite microspheres, as controlled drug release carriers, have promising potential in treating glioma. PMID:22312307

  11. Gas5 Exerts Tumor-suppressive Functions in Human Glioma Cells by Targeting miR-222

    PubMed Central

    Zhao, Xihe; Wang, Ping; Liu, Jing; Zheng, Jian; Liu, Yunhui; Chen, Jiajia; Xue, Yixue

    2015-01-01

    Aberrant expression of noncoding RNAs in glioma cells, including long noncoding RNAs (lncRNAs) and microRNAs, may participate in the progression of glioma. Encoded by Growth Arrest-Specific 5 (GAS5) gene, lncRNA Gas5 was reported to be a negative regulator for survival and proliferation of several cancers. Here, Gas5 is found to be downregulated in glioma specimens and U87 and U251 glioma cell lines. We showed that the introduction of Gas5 by plasmid transfection increased the expression of tumor suppressor Bcl-2-modifying factor (bmf) and Plexin C1 via directly targeting and reducing the expression of miR-222. Downregulated expression of miR-222 inhibited U87 and U251 cell proliferation and promoted the apoptosis by upregulating bmf. As downstream signaling molecules of bmf, Bcl-2 and Bax were involved in the process. Meanwhile, knockdown of miR-222 attenuated U87 and U251 cell migration and invasion by upregulating Plexin C1, and cofilin was a crucial regulator targeted by Plexin C1. Gas5 combined with the knockdown of miR-222 resulted in the smallest tumor volumes and the longest survivals of nude mice in vivo. In summary, we show that Gas5 suppresses tumor malignancy by downregulating miR-222, which may serve as a promising therapy for glioma. PMID:26370254

  12. Gas5 Exerts Tumor-suppressive Functions in Human Glioma Cells by Targeting miR-222.

    PubMed

    Zhao, Xihe; Wang, Ping; Liu, Jing; Zheng, Jian; Liu, Yunhui; Chen, Jiajia; Xue, Yixue

    2015-12-01

    Aberrant expression of noncoding RNAs in glioma cells, including long noncoding RNAs (lncRNAs) and microRNAs, may participate in the progression of glioma. Encoded by Growth Arrest-Specific 5 (GAS5) gene, lncRNA Gas5 was reported to be a negative regulator for survival and proliferation of several cancers. Here, Gas5 is found to be downregulated in glioma specimens and U87 and U251 glioma cell lines. We showed that the introduction of Gas5 by plasmid transfection increased the expression of tumor suppressor Bcl-2-modifying factor (bmf) and Plexin C1 via directly targeting and reducing the expression of miR-222. Downregulated expression of miR-222 inhibited U87 and U251 cell proliferation and promoted the apoptosis by upregulating bmf. As downstream signaling molecules of bmf, Bcl-2 and Bax were involved in the process. Meanwhile, knockdown of miR-222 attenuated U87 and U251 cell migration and invasion by upregulating Plexin C1, and cofilin was a crucial regulator targeted by Plexin C1. Gas5 combined with the knockdown of miR-222 resulted in the smallest tumor volumes and the longest survivals of nude mice in vivo. In summary, we show that Gas5 suppresses tumor malignancy by downregulating miR-222, which may serve as a promising therapy for glioma.

  13. Alphaxalone inhibits growth, migration and invasion of rat C6 malignant glioma cells.

    PubMed

    Sun, Huawei; Zheng, Xiaoke; Zhou, Yuehan; Zhu, Wenbo; Ou, Yanqiu; Shu, Minfeng; Gao, Xiuren; Leng, Tiandong; Qiu, Pengxin; Yan, Guangmei

    2013-10-01

    Malignant gliomas are the most devastating and aggressive brain tumors affecting the central nervous system. The insidious growth and infiltration are the most prominent characteristics of malignant gliomas, which render the current therapies for malignant gliomas including surgery, radiation and chemotherapy unsuccessful. Inhibition of infiltration as well as proliferation in combination with surgery might be more effective in the treatment of malignant gliomas. In the current study, we demonstrate the alphaxalone (3-hydroxypregnane-11,20-dione) could effectively inhibit the proliferation of C6 glioma cells in a concentration dependent manner. Moreover, this compound could also suppress the migration and invasion of C6 glioma cells at a concentration without causing significant cytotoxicity. Except the in vitro anti-glioma activity, alphaxalone effectively delayed the growth of rat C6 malignant glioma xenografts in vivo. Together, these findings suggest alphaxalone might be a promising candidate for the treatment of malignant gliomas and may also provide helpful clues for anti-glioma drugs development in future.

  14. Zn{sup 2+} induces apoptosis in human highly metastatic SHG-44 glioma cells, through inhibiting activity of the voltage-gated proton channel Hv1

    SciTech Connect

    Wang, Yifan; Zhang, Shangrong; Li, Shu Jie

    2013-08-23

    Highlights: •Hv1 is expressed in highly metastatic glioma cell. •Zn{sup 2+} ions induces apoptosis in highly metastatic glioma cells. •Zn{sup 2+} ions markedly inhibit proton secretion. •Zn{sup 2+} ions reduce the gelatinase activity. •Inhibition of Hv1 activity via Zn{sup 2+} ions can effectively retard the cancer growth. -- Abstract: In contrast to the voltage-gated K{sup +} channels, the voltage-gated proton channel Hv1 contains a voltage-sensor domain but lacks a pore domain. Here, we showed that Hv1 is expressed in the highly metastatic glioma cell SHG-44, but lowly in the poorly metastatic glioma cell U-251. Inhibition of Hv1 activity by 140 μM zinc chloride induces apoptosis in the human highly metastatic glioma cells. Zn{sup 2+} ions markedly inhibit proton secretion, and reduce the gelatinase activity in the highly metastatic glioma cells. In vivo, the glioma tumor sizes of the implantation of the SHG-44 xenografts in nude mice that were injected zinc chloride solution, were dramatically smaller than that in the controlled groups. The results demonstrated that the inhibition of Hv1 activity via Zn{sup 2+} ions can effectively retard the cancer growth and suppress the cancer metastasis by the decrease of proton extrusion and the down-regulation of gelatinase activity. Our results suggest that Zn{sup 2+} ions may be used as a potential anti-glioma drug for glioma therapy.

  15. Gab3 overexpression in human glioma mediates Akt activation and tumor cell proliferation

    PubMed Central

    Gu, Weiting; Zhang, Weifeng

    2017-01-01

    This current study tested expression and potential biological functions of Gab3 in human glioma. Gab3 mRNA and protein expression was significantly elevated in human glioma tissues and glioma cells. Its level was however low in normal brain tissues and primary human astrocytes. In both established (U251MG cell line) and primary human glioma cells, Gab3 knockdown by shRNA/siRNA significantly inhibited Akt activation and cell proliferation. Reversely, forced Gab3 overexpression in U251MG cells promoted Akt activation and cell proliferation. In vivo, the growth of U251MG tumors in nude mice was inhibited following expressing Gab3 shRNA. Akt activation in cancer tissues was also suppressed by Gab3 shRNA. Together, we conclude that Gab3 overexpression in human glioma mediates Akt activation and cancer cell proliferation. PMID:28291820

  16. Conditioned Medium from Adipose-Derived Stem Cells (ADSCs) Promotes Epithelial-to-Mesenchymal-Like Transition (EMT-Like) in Glioma Cells In vitro.

    PubMed

    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.

  17. Sulfasalazine impacts on ferroptotic cell death and alleviates the tumor microenvironment and glioma-induced brain edema

    PubMed Central

    Sehm, Tina; Fan, Zheng; Ghoochani, Ali; Rauh, Manfred; Engelhorn, Tobias; Minakaki, Georgia; Dörfler, Arnd; Klucken, Jochen; Buchfelder, Michael

    2016-01-01

    The glutamate transporter xCT (SCL7a11, system Xc-, SXC) is an emerging key player in glutamate/cysteine/glutathione homeostasis in the brain and in cancer. xCT expression correlates with the grade of malignancy. Here, we report on the use of the U.S. Food and Drug Administration and EMA-approved xCT inhibitor, sulfasalazine (SAS) in gliomas. SAS does not affect cell viability in gliomas at concentrations below 200 μM. At higher concentrations SAS becomes gliomatoxic. Mechanistically SAS inhibits xCT and induces ferroptotic cell death in glioma cells. There is no evidence for impact on autophagic flux following SAS application. However, SAS can potentiate the efficacy of the standard chemotherapeutic and autophagy-inducing agent temozolomide (Temcat, Temodal or Temodar®). We also investigated SAS in non-transformed cellular constituents of the brain. Neurons and brain tissue are almost non-responding to SAS whereas isolated astrocytes are less sensitive towards SAS toxicity compared to gliomas. In vivo SAS treatment does not affect experimental tumor growth and treated animals revealed comparable tumor volume as untreated controls. However, SAS treatment resulted in reduced glioma-derived edema and, hence, total tumor volume burden as revealed by T2-weighted magnetic resonance imaging. Altogether, we show that SAS can be utilized for targeting the glutamate antiporter xCT activity as a tumor microenvironment-normalizing drug, while crucial cytotoxic effects in brain tumors are minor. PMID:27074570

  18. Circulating tumor cell is a common property of brain glioma and promotes the monitoring system

    PubMed Central

    Gao, Faliang; Cui, Yong; Jiang, Haihui; Sui, Dali; Wang, Yonggang; Jiang, Zhongli; Zhao, Jizong; Lin, Song

    2016-01-01

    Brain glioma is the most common primary intracranial tumor characterized by dismal prognosis and frequent recurrence, yet a real-time and reliable biological approach to monitor tumor response and progression is still lacking. Recently, few studies have reported that circulating tumor cells (CTCs) could be detected in glioblastoma multiform (GBM), providing the possibility of its application in brain glioma monitoring system. But its application limits still exist, because the detection rate of CTCs is still low and was exclusively limited to high- grade gliomas. Here, we adopted an advanced integrated cellular and molecular approach of SE-iFISH to detect CTCs in the peripheral blood (PB) of patients with 7 different subtypes of brain glioma, uncovering the direct evidences of glioma migration. We identified CTCs in the PB from 24 of 31 (77%) patients with glioma in all 7 subtypes. No statistical difference of CTC incidence and count was observed in different pathological subtypes or WHO grades of glioma. Clinical data revealed that CTCs, to some extent, was superior to MRI in monitoring the treatment response and differentiating radionecrosis from recurrence of glioma. Conclusively, CTCs is a common property of brain gliomas of various pathological subtypes, which has provided an ultimate paradox for the hypothesis “soil and seed”. It can be used to monitor the microenvironment of gliomas dynamically, which will be a meaningful complement to radiographic imaging. PMID:27517490

  19. Altered splicing leads to reduced activation of CPEB3 in high-grade gliomas

    PubMed Central

    Skubal, Magdalena; Gielen, Gerrit H.; Waha, Anke; Gessi, Marco; Kaczmarczyk, Lech; Seifert, Gerald; Freihoff, Dorothee; Freihoff, Johannes; Pietsch, Torsten; Simon, Matthias; Theis, Martin; Steinhäuser, Christian; Waha, Andreas

    2016-01-01

    Cytoplasmic polyadenylation element binding proteins (CPEBs) are auxiliary translational factors that associate with consensus sequences present in 3′UTRs of mRNAs, thereby activating or repressing their translation. Knowing that CPEBs are players in cell cycle regulation and cellular senescence prompted us to investigate their contribution to the molecular pathology of gliomas–most frequent of intracranial tumors found in humans. To this end, we performed methylation analyses in the promoter regions of CPEB1-4 and identified the CPEB1 gene to be hypermethylated in tumor samples. Decreased expression of CPEB1 protein in gliomas correlated with the rising grade of tumor malignancy. Abundant expression of CPEBs2-4 was observed in several glioma specimens. Interestingly, expression of CPEB3 positively correlated with tumor progression and malignancy but negatively correlated with protein phosphorylation in the alternatively spliced region. Our data suggest that loss of CPEB3 activity in high-grade gliomas is caused by expression of alternatively spliced variants lacking the B-region that overlaps with the kinase recognition site. We conclude that deregulation of CPEB proteins may be a frequent phenomenon in gliomas and occurs on the level of transcription involving epigenetic mechanism as well as on the level of mRNA splicing, which generates isoforms with compromised biological properties. PMID:27256982

  20. Analysis of SOX2-Regulated Transcriptome in Glioma Stem Cells

    PubMed Central

    Acanda de la Rocha, Arlet M.; López-Bertoni, Hernando; Guruceaga, Elizabeth; González-Huarriz, Marisol; Martínez-Vélez, Naiara; Xipell, Enric; Fueyo, Juan; Gomez-Manzano, Candelaria

    2016-01-01

    Introduction Glioblastoma is the most malignant brain tumor in adults and is associated with poor survival despite multimodal treatments. Glioma stem-like cells (GSCs) are cells functionally defined by their self-renewal potential and the ability to reconstitute the original tumor upon orthotopic implantation. They have been postulated to be the culprit of glioma chemo- and radio-resistance ultimately leading to relapse. Understanding the molecular circuits governing the GSC compartment is essential. SOX2, a critical transcription regulator of embryonic and neural stem cell function, is deregulated in GSCs however; the precise molecular pathways regulated by this gene in GSCs remain poorly understood. Results We performed a genome-wide analysis of SOX2-regulated transcripts in GSCs, using a microarray. We identified a total of 2048 differentially expressed coding transcripts and 261 non-coding transcripts. Cell adhesion and cell-cell signaling are among the most enriched terms using Gene Ontology (GO) classification. The pathways altered after SOX2 down-modulation includes multiple cellular processes such as amino-acid metabolism and intercellular signaling cascades. We also defined and classified the set of non-coding transcripts differentially expressed regulated by SOX2 in GSCs, and validated two of them. Conclusions We present a comprehensive analysis of the transcriptome controlled by SOX2 in GSCs, gaining insights in the understanding of the potential roles of SOX2 in glioblastoma. PMID:27669421

  1. Rottlerin inhibits cell growth and invasion via down-regulation of Cdc20 in glioma cells

    PubMed Central

    Wang, Lixia; Hou, Yingying; Yin, Xuyuan; Su, Jingna; Zhao, Zhe; Ye, Xiantao; Zhou, Xiuxia; Zhou, Li; Wang, Zhiwei

    2016-01-01

    Rottlerin, isolated from a medicinal plant Mallotus phillippinensis, has been demonstrated to inhibit cellular growth and induce cytoxicity in glioblastoma cell lines through inhibition of calmodulin-dependent protein kinase III. Emerging evidence suggests that rottlerin exerts its antitumor activity as a protein kinase C inhibitor. Although further studies revealed that rottlerin regulated multiple signaling pathways to suppress tumor cell growth, the exact molecular insight on rottlerin-mediated tumor inhibition is not fully elucidated. In the current study, we determine the function of rottlerin on glioma cell growth, apoptosis, cell cycle, migration and invasion. We found that rottlerin inhibited cell growth, migration, invasion, but induced apoptosis and cell cycle arrest. Mechanistically, the expression of Cdc20 oncoprotein was measured by the RT-PCR and Western blot analysis in glioma cells treated with rottlerin. We observed that rottlerin significantly inhibited the expression of Cdc20 in glioma cells, implying that Cdc20 could be a novel target of rottlerin. In line with this, over-expression of Cdc20 decreased rottlerin-induced cell growth inhibition and apoptosis, whereas down-regulation of Cdc20 by its shRNA promotes rottlerin-induced anti-tumor activity. Our findings indicted that rottlerin could exert its tumor suppressive function by inhibiting Cdc20 pathway which is constitutively active in glioma cells. Therefore, down-regulation of Cdc20 by rottlerin could be a promising therapeutic strategy for the treatment of glioma. PMID:27626499

  2. Anti-tumor activity of phenoxybenzamine hydrochloride on malignant glioma cells.

    PubMed

    Lin, Xian-Bin; Jiang, Lei; Ding, Mao-Hua; Chen, Zhen-Hua; Bao, Yi; Chen, Yi; Sun, Wei; Zhang, Chen-Ran; Hu, Hong-Kang; Cai, Zhen; Lu, Cheng-Yin; Zhou, Jue-Yu; Qian, Jun; Wu, Xiao-Jun; Jin, Wei-Lin; Hu, Guo-Han

    2016-03-01

    Phenoxybenzamine hydrochloride (PHEN) is a selective antagonist of both α-adrenoceptor and calmodulin that exhibits anticancer properties. The aim of this study was to explore the anti-tumor function of PHEN in glioma. Cell proliferation assay was used to assess glioma cell growth. Migration and invasion capacity of glioma cells was monitored by wound-healing and transwell assay, respectively. Neurosphere formation test was adopted for the tumorigenesis of glioma cells, which was also confirmed by soft agar cloning formation test in vitro and a nude mouse model in vivo. Finally, we explored the potential pathway utilized by PHEN using Western blot and immunofluoresce staining. PHEN exhibited a significant inhibitory effect on the proliferation of both U251 and U87MG glioma cell lines in a positive dose-dependent manner. PHEN apparently attenuated the malignancy of glioma in terms of migration and invasion and also suppressed the tumorigenic capacity both in vitro and in vivo. Mechanism study showed that PHEN promoted tumor suppression by inhibiting the TrkB-Akt pathway. The results of the present study demonstrated that PHEN suppressed the proliferation, migration, invasion, and tumorigenesis of glioma cells, induced LINGO-1 expression, and inhibited the TrkB-Akt pathway, which may prove to be the mechanisms underlying the anti-tumor effect of PHEN on glioma cells.

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

    NASA Astrophysics Data System (ADS)

    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.

  4. Senescence from glioma stem cell differentiation promotes tumor growth

    PubMed Central

    Ouchi, Rie; Okabe, Sachiko; Migita, Toshiro; Nakano, Ichiro; Seimiya, Hiroyuki

    2016-01-01

    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. PMID:26775840

  5. Decorin-mediated inhibition of the migration of U87MG glioma cells involves activation of autophagy and suppression of TGF-β signaling.

    PubMed

    Yao, Ting; Zhang, Chen-Guang; Gong, Ming-Tao; Zhang, Min; Wang, Lei; Ding, Wei

    2016-07-01

    Decorin (DCN) is a major member of the small leucine-rich proteoglycan (SLRP) family that is critically involved in tumorigenesis and the development of metastasis of cancers, including glioma. Overexpression of DCN was indicated to suppress glioma cell growth. However, the role of DCN in the migration of glioma cells remain elusive. In this study, we found that treatment with exogenous DCN inhibited the adhesion and migration of U87MG glioma cells with down-regulation of TGF-β signaling. DCN also activated autophagy, as indicated by monodansylcadaverine (MDC) staining, increase in LC3 I/LC3 II conversion, and p62/SQSTM1 degradation in U87MG cells. The increased activity of autophagy was found to be connected to the inhibition on glioma cell migration. Knockdown of DCN expression or the disruption of autophagy with 3-methyladenine (3-MA) was able to reduce the suppression on cell adhesion and migration induced by DCN. When U87MG cells were treated with temozolomide (TMZ), induction of autophagy and up-regulation of DCN were observed, accompanied by suppressed cell adhesion and migration. Transfection of siRNA targeting DCN attenuated the suppressive effect of TMZ on glioma cell migration and adhesion. Our results indicated that the migration of glioma cells was under the control of the active status of autophagy, with DCN serving as a key player, as well as an indicator of the outcome. Therefore, it is suggested that autophagy-modulating reagents could be considered for the treatment of invasive glioma.

  6. Increasing the efficacy of antitumor glioma vaccines by photodynamic therapy and local injection of allogeneic glioma cells

    NASA Astrophysics Data System (ADS)

    Christie, Catherine E.; Peng, Qian; Madsen, Steen J.; Uzal, Francisco A.; Hirschberg, Henry

    2016-03-01

    Immunotherapy of brain tumors involves the stimulation of an antitumor immune response. This type of therapy can be targeted specifically to tumor cells thus sparing surrounding normal brain. Due to the presence of the blood-brain barrier, the brain is relatively isolated from the systemic circulation and, as such, the initiation of significant immune responses is more limited than other types of cancers. The purpose of this study was to show that the efficacy of tumor primed antigen presenting macrophage vaccines could be increased by: (1) PDT of the priming tumor cells, and (2) injection of allogeneic glioma cells directly into brain tumors. Experiments were conducted in an in vivo brain tumor model using Fisher rats and BT4C (allogeneic) and F98 (syngeneic) glioma cells. Preliminary results showed that vaccination alone had significantly less inhibitory effect on F98 tumor growth compared to the combination of vaccination and allogeneic cell (BT4C) injection.

  7. FIBULIN-3 IS UNIQUELY UPREGULATED IN MALIGNANT GLIOMAS AND PROMOTES TUMOR CELL MOTILITY AND INVASION

    PubMed Central

    Hu, Bin; Thirtamara-Rajamani, Keerthi K.; Sim, Hosung; Viapiano, Mariano S.

    2013-01-01

    Malignant gliomas are highly invasive tumors with an almost invariably rapid and lethal outcome. Surgery and chemoradiotherapy fail to remove resistant tumor cells that disperse within normal tissue, which are a major cause for disease progression and therapy failure. Infiltration of the neural parenchyma is a distinctive property of malignant gliomas compared to other solid tumors. Thus, glioma cells are thought to produce unique molecular changes that remodel the neural extracellular matrix and form a microenvironment permissive for their motility. Here we describe the unique expression and pro-invasive role of fibulin-3, a mesenchymal matrix protein specifically upregulated in gliomas. Fibulin-3 is downregulated in peripheral tumors and thought to inhibit tumor growth. However, we found fibulin-3 highly upregulated in gliomas and cultured glioma cells, although the protein was undetectable in normal brain or cultured astrocytes. Overexpression and knockdown experiments revealed that fibulin-3 did not seem to affect glioma cell morphology or proliferation, but enhanced substrate-specific cell adhesion and promoted cell motility and dispersion in organotypic cultures. Moreover, orthotopic implantation of fibulin-3-overexpressing glioma cells resulted in diffuse tumors with increased volume and rostrocaudal extension compared to controls. Tumors and cultured cells overexpressing fibulin-3 also showed elevated expression and activity of matrix metalloproteases, such as MMP-2/9 and ADAMTS-5. Taken together, our results suggest that fibulin-3 has a unique expression and pro-tumoral role in gliomas, and could be a potential target against tumor progression. Strategies against this glioma-specific matrix component could disrupt invasive mechanisms and restrict dissemination of these tumors. PMID:19887559

  8. Impact of the coxsackie and adenovirus receptor (CAR) on glioma cell growth and invasion: requirement for the C-terminal domain.

    PubMed

    Huang, Kuo-Cheng; Altinoz, Meric; Wosik, Karolina; Larochelle, Nancy; Koty, Zafiro; Zhu, Lixia; Holland, Paul C; Nalbantoglu, Josephine

    2005-02-20

    Expression of the coxsackie and adenovirus receptor (CAR) is downregulated in malignant glioma cell lines and is barely detectable in high-grade primary astrocytoma (glioblastoma multiforme). We determined the effect of forced CAR expression on the invasion and growth of the human glioma cell line U87-MG, which does not express any CAR. Although retrovirally mediated expression of full-length CAR in U87-MG cells did not affect monolayer growth in vitro, it did reduce glioma cell invasion in a 3-dimensional spheroid model. Furthermore, in xenograft experiments, intracerebral implantation of glioma cells expressing full-length CAR resulted in tumors with a significantly reduced volume compared to tumors generated by control vector-transduced U87-MG cells. In contrast, U87-MG cells expressing transmembrane CAR with a deletion of the entire cytoplasmic domain (except for the first 2 intracellular juxtamembrane cysteine amino acids) had rates of invasion and tumor growth that were similar to those of the control cells. This difference in behavior between the 2 forms of CAR was not due to improper cell surface localization of the cytoplasmically deleted CAR as determined by comparable immunostaining of unpermeabilized cells, equivalent adenoviral transduction of the cells and similar extent of fractionation into lipid-rich domains. Taken together, these results suggest that the decrease or loss of CAR expression in malignant glioma may confer a selective advantage in growth and invasion to these tumors.

  9. GSK621 Targets Glioma Cells via Activating AMP-Activated Protein Kinase Signalings

    PubMed Central

    Jiang, Hong; Liu, Wei; Zhan, Shi-Kun; Pan, Yi-Xin; Bian, Liu-Guan; Sun, Bomin; Sun, Qing-Fang; Pan, Si-Jian

    2016-01-01

    Here, we studied the anti-glioma cell activity by a novel AMP-activated protein kinase (AMPK) activator GSK621. We showed that GSK621 was cytotoxic to human glioma cells (U87MG and U251MG lines), possibly via provoking caspase-dependent apoptotic cell death. Its cytotoxicity was alleviated by caspase inhibitors. GSK621 activated AMPK to inhibit mammalian target of rapamycin (mTOR) and downregulate Tetraspanin 8 (Tspan8) in glioma cells. AMPK inhibition, through shRNA knockdown of AMPKα or introduction of a dominant negative (T172A) AMPKα, almost reversed GSK621-induced AMPK activation, mTOR inhibition and Tspan8 degradation. Consequently, GSK621’s cytotoxicity in glioma cells was also significantly attenuated by AMPKα knockdown or mutation. Further studies showed that GSK621, at a relatively low concentration, significantly potentiated temozolomide (TMZ)’s sensitivity and lethality against glioma cells. We summarized that GSK621 inhibits human glioma cells possibly via activating AMPK signaling. This novel AMPK activator could be a novel and promising anti-glioma cell agent. PMID:27532105

  10. Suppression of autophagy augments the radiosensitizing effects of STAT3 inhibition on human glioma cells

    SciTech Connect

    Yuan, Xiaopeng; Du, Jie; Hua, Song; Zhang, Haowen; Gu, Cheng; Wang, Jie; Yang, Lei; Huang, Jianfeng; Yu, Jiahua Liu, Fenju

    2015-01-15

    Radiotherapy is an essential component of the standard therapy for newly diagnosed glioblastoma. To increase the radiosensitivity of glioma cells is a feasible solution to improve the therapeutic effects. It has been suggested that inhibition of signal transducer and activator of transcription 3 (STAT3) can radiosensitize glioma cells, probably via the activation of mitochondrial apoptotic pathway. In this study, human malignant glioma cells, U251 and A172, were treated with an STAT3 inhibitor, WP1066, or a short hairpin RNA plasmid targeting STAT3 to suppress the activation of STAT3 signaling. The radiosensitizing effects of STAT3 inhibition were confirmed in glioma cells. Intriguingly, combination of ionizing radiation exposure and STAT3 inhibition triggered a pronounced increase of autophagy flux. To explore the role of autophagy, glioma cells were treated with 3-methyladenine or siRNA for autophagy-related gene 5, and it was demonstrated that inhibition of autophagy further strengthened the radiosensitizing effects of STAT3 inhibition. Accordingly, more apoptotic cells were induced by the dual inhibition of autophagy and STAT3 signaling. In conclusion, our data revealed a protective role of autophagy in the radiosensitizing effects of STAT3 inhibition, and inhibition of both autophagy and STAT3 might be a potential therapeutic strategy to increase the radiosensitivity of glioma cells. - Highlights: • Inactivation of STAT3 signaling radiosensitizes malignant glioma cells. • STAT3 inhibition triggers a significant increase of autophagy flux induced by ionizing radiation in glioma cells. • Suppression of autophagy further strengthens the radiosensitizing effects of STAT3 inhibition in glioma cells. • Dual inhibition of autophagy and STAT3 induce massive apoptotic cells upon exposure to ionizing radiation.

  11. AKT Axis, miR-21, and RECK Play Pivotal Roles in Dihydroartemisinin Killing Malignant Glioma Cells

    PubMed Central

    Shao, Ying-Ying; Zhang, Tao-Lan; Wu, Lan-Xiang; Zou, He-Cun; Li, Shuang; Huang, Jin; Zhou, Hong-Hao

    2017-01-01

    Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, is known to play important roles in inhibiting proliferation rate, inducing apoptosis, as well as hindering the metastasis and invasion of glioma cells, but the underlying mechanisms are still unclear so far. In this study, methyl thiazolyl tetrazolium (MTT), colony-forming, wound healing, invasion, and apoptosis assays were performed to investigate the effect of DHA on malignant glioma cells. Results showed that DHA induced apoptosis of malignant glioma cells through Protein Kinase B (AKT) axis, induced death of malignant glioma cells by downregulating miR-21, and inhibited the invasion of malignant glioma cells corresponding with up-regulation of the reversion-inducing-cysteine-rich protein with kazal motifs (RECK). These results revealed that AKT axis, miR-21, and RECK play pivotal roles in DHA killing malignant glioma cells, suggesting that DHA is a potential agent for treating glioma. PMID:28208619

  12. Characterization of Heparan Sulfate Proteoglycan-positive Recycling Endosomes Isolated from Glioma Cells

    PubMed Central

    A. PODYMA-INOUE, KATARZYNA; MORIWAKI, TAKUYA; R. RAJAPAKSHE, ANUPAMA; TERASAWA, KAZUE; HARA-YOKOYAMA, MIKI

    2016-01-01

    Background: Heparan sulfate proteoglycans (HSPGs)-dependent endocytic events have been involved in glioma progression. Thus, comprehensive understanding of the intracellular trafficking complexes formed in presence of HSPGs would be important for development of glioma treatments. Materials and Methods: Subcellular fractionation was used to separate vesicles containing HSPGs from the rat C6 glioma cell line. Isolated HSPG-positive vesicles were further characterized with liquid chromatography-mass spectrometry. Results: The HSPG-positive vesicular fractions, distinct from plasma membrane-derived material, were enriched in endocytic marker, Rab11. Proteomic analysis identified more than two hundred proteins to be associated with vesicular membrane, among them, over eighty were related to endosomal uptake, recycling or vesicular transport. Conclusion: Part of HSPGs in glioma cells is internalized through clathrin-dependent endocytosis and undergo recycling. The development of compounds regulating HSPG-mediated trafficking will likely enable design of effective glioma treatment. PMID:27807067

  13. Deubiquitinase USP9X deubiquitinates β-catenin and promotes high grade glioma cell growth

    PubMed Central

    Wang, Zhihao; Yang, Chunxu; Ouyang, Wen; Zhou, Fuxiang; Zhou, Yunfeng; Xie, Conghua

    2016-01-01

    β-catenin is a crucial signal transduction molecule in the Wnt/β-catenin signal pathway, and increased β-catenin expression has consistently been found in high grade gliomas. However, the mechanisms responsible for β-catenin overexpression have remained elusive. Here we show that the deubiquitinase USP9X stabilizes β-catenin and thereby promotes high grade glioma cell growth. USP9X binds β-catenin and removes the Lys 48-linked polyubiquitin chains that normally mark β-catenin for proteasomal degradation. Increased USP9X expression correlates with increased β-catenin protein in high grade glioma tissues. Moreover, patients with high grade glioma overexpressing USP9X have a poor prognosis. Knockdown of USP9X suppresses cell proliferation, inhibits G1/S phase conversion, and induces apoptosis in U251 and A172 cells. Interestingly, c-Myc and cyclinD1, which are important downstream target genes in the Wnt/β-catenin signal pathway, also show decreased expression in cells with siRNA-mediated down-regulation of USP9X. Down-regulation of USP9X also consistently inhibits the tumorigenicity of primary glioma cells in vivo. In summary, these results indicate that USP9X stabilizes β-catenin and activates Wnt/β-catenin signal pathway to promote glioma cell proliferation and survival. USP9X could also potentially be a novel therapeutic target for high grade gliomas. PMID:27783990

  14. Intraoperative neuropathology of glioma recurrence: cell detection and classification

    NASA Astrophysics Data System (ADS)

    Abas, Fazly S.; Gokozan, Hamza N.; Goksel, Behiye; Otero, Jose J.; Gurcan, Metin N.

    2016-03-01

    Intraoperative neuropathology of glioma recurrence represents significant visual challenges to pathologists as they carry significant clinical implications. For example, rendering a diagnosis of recurrent glioma can help the surgeon decide to perform more aggressive resection if surgically appropriate. In addition, the success of recent clinical trials for intraoperative administration of therapies, such as inoculation with oncolytic viruses, may suggest that refinement of the intraoperative diagnosis during neurosurgery is an emerging need for pathologists. Typically, these diagnoses require rapid/STAT processing lasting only 20-30 minutes after receipt from neurosurgery. In this relatively short time frame, only dyes, such as hematoxylin and eosin (H and E), can be implemented. The visual challenge lies in the fact that these patients have undergone chemotherapy and radiation, both of which induce cytological atypia in astrocytes, and pathologists are unable to implement helpful biomarkers in their diagnoses. Therefore, there is a need to help pathologists differentiate between astrocytes that are cytologically atypical due to treatment versus infiltrating, recurrent, neoplastic astrocytes. This study focuses on classification of neoplastic versus non-neoplastic astrocytes with the long term goal of providing a better neuropathological computer-aided consultation via classification of cells into reactive gliosis versus recurrent glioma. We present a method to detect cells in H and E stained digitized slides of intraoperative cytologic preparations. The method uses a combination of the `value' component of the HSV color space and `b*' component of the CIE L*a*b* color space to create an enhanced image that suppresses the background while revealing cells on an image. A composite image is formed based on the morphological closing of the hue-luminance combined image. Geometrical and textural features extracted from Discrete Wavelet Frames and combined to classify

  15. Memantine Induces NMDAR1-Mediated Autophagic Cell Death in Malignant Glioma Cells

    PubMed Central

    Yoon, Wan-Soo; Yeom, Mi-Young; Kang, Eun-Sun; Chung, Yong-An; Chung, Dong-Sup; Jeun, Sin-Soo

    2017-01-01

    Objective Autophagy is one of the key responses of cells to programmed cell death. Memantine, an approved anti-dementia drug, has an antiproliferative effect on cancer cells but the mechanism is poorly understood. The aim of the present study was to test the possibility of induction of autophagic cell death by memantine in glioma cell lines. Methods Glioma cell lines (T-98 G and U-251 MG) were used for this study. Results The antiproliferative effect of memantine was shown on T-98 G cells, which expressed N-methyl-D-aspartate 1 receptor (NMDAR1). Memantine increased the autophagic-related proteins as the conversion ratio of light chain protein 3-II (LC3-II)-/LC3-I and the expression of beclin-1. Memantine also increased formation of autophagic vacuoles observed under a transmission electron microscope. Transfection of small interfering RNA (siRNA) to knock down NMDAR1 in the glioma cells induced resistance to memantine and decreased the LC3-II/LC3-I ratio in T-98 G cells. Conclusion Our study demonstrates that in glioma cells, memantine inhibits proliferation and induces autophagy mediated by NMDAR1. PMID:28264232

  16. Endothelial Differentiation of Adipose Tissue-Derived Mesenchymal Stromal Cells in Glioma Tumors: Implications for Cell-Based Therapy

    PubMed Central

    Bagó, Juli R; Alieva, Maria; Soler, Carolina; Rubio, Núria; Blanco, Jerónimo

    2013-01-01

    Multipotent human adipose tissue mesenchymal stromal cells (hAMSCs) are promising therapy vehicles with tumor-homing capacity that can be easily modified to deliver cytotoxicity activating systems in the proximity of tumors. In a previous work, we observed that hAMSCs are very effective delivering cytotoxicity to glioma tumors. However, these results were difficult to reconcile with the relatively few hAMSCs surviving implantation. We use a bioluminescence imaging (BLI) platform to analyze the behavior of bioluminescent hAMSCs expressing HSV-tTK in a U87 glioma model and gain insight into the therapeutic mechanisms. Tumor-implanted hAMSCs express the endothelial marker PECAM1(CD31), integrate in tumor vessels and associate with CD133-expressing glioma stem cells (GSC). Inhibition of endothelial lineage differentiation in hAMSCs by Notch1 shRNA had no effect on their tumor homing and growth-promoting capacity but abolished the association of hAMSCs with tumor vessels and CD133+ tumor cells and significantly reduced their tumor-killing capacity. The current strategy allowed the study of tumor/stroma interactions, showed that tumor promotion and tumor-killing capacities of hAMSCs are based on different mechanisms. Our data strongly suggest that the therapeutic effectiveness of hAMSCs results from their association with special tumor vascular structures that also contain GSCs. PMID:23760448

  17. Overexpression of FZD7 promotes glioma cell proliferation by upregulating TAZ

    PubMed Central

    Tian, Tian

    2016-01-01

    Gliomas are the most prevalent type of primary brain tumors in adults, accounting for more than 40% of neoplasm in the central nervous system. Frizzled-7 (FZD7) is a seven-pass trans-membrane Wnt receptor that plays a critical role in the development of various tumors. In this study, we detected high-level FZD7 expression in glioma and its overexpression was associated with advanced tumor stage. In vitro functional assays showed that forced overexpression of FZD7 promoted proliferation of gliomas cells, whereas knockdown of endogenous FZD7 significantly suppressed proliferation ability of these cells. In a xenograft assay, FZD7 was also found to promote the growth of glioma cells. We further found that FZD7 could activate transcriptional coactivator with PDZ-binding motif (TAZ), and TAZ was required for FZD7 to promote cell proliferation in glioma. Furthermore, the univariate analysis of survival shows that glioma patients with high FZD7 expression have a shorter survival. In conclusion, our findings demonstrate that FZD7 may promote glioma cell proliferation via upregulation of TAZ. PMID:27852064

  18. Transformation of quiescent adult oligodendrocyte precursor cells into malignant glioma through a multistep reactivation process.

    PubMed

    Galvao, Rui Pedro; Kasina, Anita; McNeill, Robert S; Harbin, Jordan E; Foreman, Oded; Verhaak, Roel G W; Nishiyama, Akiko; Miller, C Ryan; Zong, Hui

    2014-10-07

    How malignant gliomas arise in a mature brain remains a mystery, hindering the development of preventive and therapeutic interventions. We previously showed that oligodendrocyte precursor cells (OPCs) can be transformed into glioma when mutations are introduced perinatally. However, adult OPCs rarely proliferate compared with their perinatal counterparts. Whether these relatively quiescent cells have the potential to transform is unknown, which is a critical question considering the late onset of human glioma. Additionally, the premalignant events taking place between initial mutation and a fully developed tumor mass are particularly poorly understood in glioma. Here we used a temporally controllable Cre transgene to delete p53 and NF1 specifically in adult OPCs and demonstrated that these cells consistently give rise to malignant gliomas. To investigate the transforming process of quiescent adult OPCs, we then tracked these cells throughout the premalignant phase, which revealed a dynamic multistep transformation, starting with rapid but transient hyperproliferative reactivation, followed by a long period of dormancy, and then final malignant transformation. Using pharmacological approaches, we discovered that mammalian target of rapamycin signaling is critical for both the initial OPC reactivation step and late-stage tumor cell proliferation and thus might be a potential target for both glioma prevention and treatment. In summary, our results firmly establish the transforming potential of adult OPCs and reveal an actionable multiphasic reactivation process that turns slowly dividing OPCs into malignant gliomas.

  19. Optic glioma

    MedlinePlus

    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 ...

  20. Sensitivity of C6 Glioma Cells Carrying the Human Poliovirus Receptor to Oncolytic Polioviruses.

    PubMed

    Sosnovtseva, A O; Lipatova, A V; Grinenko, N F; Baklaushev, V P; Chumakov, P M; Chekhonin, V P

    2016-10-01

    A humanized line of rat C6 glioma cells expressing human poliovirus receptor was obtained and tested for the sensitivity to oncolytic effects of vaccine strains of type 1, 2, and 3 polioviruses. Presentation of the poliovirus receptor on the surface of C6 glioma cells was shown to be a necessary condition for the interaction of cells with polioviruses, but insufficient for complete poliovirus oncolysis.

  1. Loss of SOCS3 in myeloid cells prolongs survival in a syngeneic model of glioma

    PubMed Central

    McFarland, Braden C.; Marks, Margaret P.; Rowse, Amber L.; Fehling, Samuel C.; Gerigk, Magda; Qin, Hongwei; Benveniste, Etty N.

    2016-01-01

    In glioma, microglia and macrophages are the largest population of tumor-infiltrating cells, referred to as glioma associated macrophages (GAMs). Herein, we sought to determine the role of Suppressor of Cytokine Signaling 3 (SOCS3), a negative regulator of Signal Transducer and Activator of Transcription 3 (STAT3), in GAM functionality in glioma. We utilized a conditional model in which SOCS3 deletion is restricted to the myeloid cell population. We found that SOCS3-deficient bone marrow-derived macrophages display enhanced and prolonged expression of pro-inflammatory M1 cytokines when exposed to glioma tumor cell conditioned medium in vitro. Moreover, we found that deletion of SOCS3 in the myeloid cell population delays intracranial tumor growth and increases survival of mice bearing orthotopic glioma tumors in vivo. Although intracranial tumors from mice with SOCS3-deficient myeloid cells appear histologically similar to control mice, we observed that loss of SOCS3 in myeloid cells results in decreased M2 polarized macrophage infiltration in the tumors. Furthermore, loss of SOCS3 in myeloid cells results in increased CD8+ T-cell and decreased regulatory T-cell infiltration in the tumors. These findings demonstrate a beneficial effect of M1 polarized macrophages on suppressing glioma tumor growth, and highlight the importance of immune cells in the tumor microenvironment. PMID:26967393

  2. Atypical nuclear localization of VIP receptors in glioma cell lines and patients

    SciTech Connect

    Barbarin, Alice; Séité, Paule; Godet, Julie; Bensalma, Souheyla; Muller, Jean-Marc; Chadéneau, Corinne

    2014-11-28

    Highlights: • The VIP receptor VPAC1 contains a putative NLS signal. • VPAC1 is predominantly nuclear in GBM cell lines but not VPAC2. • Non-nuclear VPAC1/2 protein expression is correlated with glioma grade. • Nuclear VPAC1 is observed in 50% of stage IV glioma (GBM). - Abstract: An increasing number of G protein-coupled receptors, like receptors for vasoactive intestinal peptide (VIP), are found in cell nucleus. As VIP receptors are involved in the regulation of glioma cell proliferation and migration, we investigated the expression and the nuclear localization of the VIP receptors VPAC1 and VPAC2 in this cancer. First, by applying Western blot and immunofluorescence detection in three human glioblastoma (GBM) cell lines, we observed a strong nuclear staining for the VPAC1 receptor and a weak nuclear VPAC2 receptor staining. Second, immunohistochemical staining of VPAC1 and VPAC2 on tissue microarrays (TMA) showed that the two receptors were expressed in normal brain and glioma tissues. Expression in the non-nuclear compartment of the two receptors significantly increased with the grade of the tumors. Analysis of nuclear staining revealed a significant increase of VPAC1 staining with glioma grade, with up to 50% of GBM displaying strong VPAC1 nuclear staining, whereas nuclear VPAC2 staining remained marginal. The increase in VPAC receptor expression with glioma grades and the enhanced nuclear localization of the VPAC1 receptors in GBM might be of importance for glioma progression.

  3. Mesenchymal Stem Cells Isolated From Human Gliomas Increase Proliferation and Maintain Stemness of Glioma Stem Cells Through the IL-6/gp130/STAT3 Pathway.

    PubMed

    Hossain, Anwar; Gumin, Joy; Gao, Feng; Figueroa, Javier; Shinojima, Naoki; Takezaki, Tatsuya; Priebe, Waldemar; Villarreal, Diana; Kang, Seok-Gu; Joyce, Celine; Sulman, Erik; Wang, Qianghu; Marini, Frank C; Andreeff, Michael; Colman, Howard; Lang, Frederick F

    2015-08-01

    Although mesenchymal stem cells (MSCs) have been implicated as stromal components of several cancers, their ultimate contribution to tumorigenesis and their potential to drive cancer stem cells, particularly in the unique microenvironment of human brain tumors, remain largely undefined. Consequently, using established criteria, we isolated glioma-associated-human MSCs (GA-hMSCs) from fresh human glioma surgical specimens for the first time. We show that these GA-hMSCs are nontumorigenic stromal cells that are phenotypically similar to prototypical bone marrow-MSCs. Low-passage genomic sequencing analyses comparing GA-hMSCs with matched tumor-initiating glioma stem cells (GSCs) suggest that most GA-hMSCs (60%) are normal cells recruited to the tumor (group 1 GA-hMSCs), although, rarely (10%), GA-hMSCs may differentiate directly from GSCs (group 2 GA-hMSCs) or display genetic patterns intermediate between these groups (group 3 GA-hMSCs). Importantly, GA-hMSCs increase proliferation and self-renewal of GSCs in vitro and enhance GSC tumorigenicity and mesenchymal features in vivo, confirming their functional significance within the GSC niche. These effects are mediated by GA-hMSC-secreted interleukin-6, which activates STAT3 in GSCs. Our results establish GA-hMSCs as a potentially new stromal component of gliomas that drives the aggressiveness of GSCs, and point to GA-hMSCs as a novel therapeutic target within gliomas.

  4. Mesenchymal Stem Cells Isolated from Human Gliomas Increase Proliferation and Maintain Stemness of Glioma Stem Cells Through the IL-6/gp130/STAT3 pathway

    PubMed Central

    Hossain, Anwar; Gumin, Joy; Gao, Feng; Figueroa, Javier; Shinojima, Naoki; Takezaki, Tatsuya; Priebe, Waldemar; Villarreal, Diana; Kang, Seok-Gu; Joyce, Celine; Sulman, Erik; Wang, Qianghu; Marini, Frank C.; Andreeff, Michael; Colman, Howard; Lang, Frederick F.

    2015-01-01

    Although mesenchymal stem cells (MSCs) have been implicated as stromal components of several cancers, their ultimate contribution to tumorigenesis and their potential to drive cancer stem cells, particularly in the unique microenvironment of human brain tumors, remains largely undefined. Consequently, using established criteria, we isolated glioma-associated-human MSCs (GA-hMSCs) from fresh human glioma surgical specimens for the first time. We show that these GA-hMSCs are nontumorigenic stromal cells that are phenotypically similar to prototypical bone marrow-MSCs. Low-passage genomic sequencing analyses comparing GA-hMSCs with matched tumor-initiating glioma stem cells (GSCs) suggest that most GA-hMSCs (60%) are normal cells recruited to the tumor (Group 1 GA-hMSCs), although, rarely (10%), GA-hMSCs may differentiate directly from GSCs (Group 2 GA-hMSCs) or display genetic patterns intermediate between these groups (Group 3 GA-hMSCs). Importantly, GA-hMSCs increase proliferation and self-renewal of GSCs in vitro, and enhance GSC tumorigenicity and mesenchymal features in vivo, confirming their functional significance within the GSC niche. These effects are mediated by GA-hMSC-secreted interleukin-6, which activates STAT3 in GSCs. Our results establish GA-hMSCs as a potentially new stromal component of gliomas that drives the aggressiveness of GSCs, and point to GA-hMSCs as a novel therapeutic target within gliomas. PMID:25966666

  5. Natural killer cells require monocytic Gr-1(+)/CD11b(+) myeloid cells to eradicate orthotopically engrafted glioma cells.

    PubMed

    Baker, Gregory J; Chockley, Peter; Zamler, Daniel; Castro, Maria G; Lowenstein, Pedro R

    2016-06-01

    Malignant gliomas are resistant to natural killer (NK) cell immune surveillance. However, the mechanisms used by these cancers to suppress antitumor NK cell activity remain poorly understood. We have recently reported on a novel mechanism of innate immune evasion characterized by the overexpression of the carbohydrate-binding protein galectin-1 by both mouse and rat malignant glioma. Here, we investigate the cytokine profile of galectin-1-deficient GL26 cells and describe the process by which these tumors are targeted by the early innate immune system in RAG1(-/-) and C57BL/6J mice. Our data reveal that galectin-1 knockdown in GL26 cells heightens their inflammatory status leading to the rapid recruitment of Gr-1(+)/CD11b(+) myeloid cells and NK1.1(+) NK cells into the brain tumor microenvironment, culminating in tumor clearance. We show that immunodepletion of Gr-1(+) myeloid cells in RAG1(-/-) mice permits the growth of galectin-1-deficient glioma despite the presence of NK cells, thus demonstrating an essential role for myeloid cells in the clearance of galectin-1-deficient glioma. Further characterization of tumor-infiltrating Gr-1(+)/CD11b(+) cells reveals that these cells also express CCR2 and Ly-6C, markers consistent with inflammatory monocytes. Our results demonstrate that Gr-1(+)/CD11b(+) myeloid cells, often referred to as myeloid-derived suppressor cells (MDSCs), are required for antitumor NK cell activity against galectin-1-deficient GL26 glioma. We conclude that glioma-derived galectin-1 represents an important factor in dictating the phenotypic behavior of monocytic Gr-1(+)/CD11b(+) myeloid cells. Galectin-1 suppression may be a valuable treatment approach for clinical glioma by promoting their innate immune-mediated recognition and clearance through the concerted effort of innate myeloid and lymphoid cell lineages.

  6. Controlled Payload Release by Magnetic Field Triggered Neural Stem Cell Destruction for Malignant Glioma Treatment

    PubMed Central

    Muroski, Megan E.; Morshed, Ramin A.; Cheng, Yu; Vemulkar, Tarun; Mansell, Rhodri; Han, Yu; Zhang, Lingjiao; Aboody, Karen S.; Cowburn, Russell P.; Lesniak, Maciej S.

    2016-01-01

    Stem cells have recently garnered attention as drug and particle carriers to sites of tumors, due to their natural ability to track to the site of interest. Specifically, neural stem cells (NSCs) have demonstrated to be a promising candidate for delivering therapeutics to malignant glioma, a primary brain tumor that is not curable by current treatments, and inevitably fatal. In this article, we demonstrate that NSCs are able to internalize 2 μm magnetic discs (SD), without affecting the health of the cells. The SD can then be remotely triggered in an applied 1 T rotating magnetic field to deliver a payload. Furthermore, we use this NSC-SD delivery system to deliver the SD themselves as a therapeutic agent to mechanically destroy glioma cells. NSCs were incubated with the SD overnight before treatment with a 1T rotating magnetic field to trigger the SD release. The potential timed release effects of the magnetic particles were tested with migration assays, confocal microscopy and immunohistochemistry for apoptosis. After the magnetic field triggered SD release, glioma cells were added and allowed to internalize the particles. Once internalized, another dose of the magnetic field treatment was administered to trigger mechanically induced apoptotic cell death of the glioma cells by the rotating SD. We are able to determine that NSC-SD and magnetic field treatment can achieve over 50% glioma cell death when loaded at 50 SD/cell, making this a promising therapeutic for the treatment of glioma. PMID:26734932

  7. Controlled Payload Release by Magnetic Field Triggered Neural Stem Cell Destruction for Malignant Glioma Treatment.

    PubMed

    Muroski, Megan E; Morshed, Ramin A; Cheng, Yu; Vemulkar, Tarun; Mansell, Rhodri; Han, Yu; Zhang, Lingjiao; Aboody, Karen S; Cowburn, Russell P; Lesniak, Maciej S

    2016-01-01

    Stem cells have recently garnered attention as drug and particle carriers to sites of tumors, due to their natural ability to track to the site of interest. Specifically, neural stem cells (NSCs) have demonstrated to be a promising candidate for delivering therapeutics to malignant glioma, a primary brain tumor that is not curable by current treatments, and inevitably fatal. In this article, we demonstrate that NSCs are able to internalize 2 μm magnetic discs (SD), without affecting the health of the cells. The SD can then be remotely triggered in an applied 1 T rotating magnetic field to deliver a payload. Furthermore, we use this NSC-SD delivery system to deliver the SD themselves as a therapeutic agent to mechanically destroy glioma cells. NSCs were incubated with the SD overnight before treatment with a 1T rotating magnetic field to trigger the SD release. The potential timed release effects of the magnetic particles were tested with migration assays, confocal microscopy and immunohistochemistry for apoptosis. After the magnetic field triggered SD release, glioma cells were added and allowed to internalize the particles. Once internalized, another dose of the magnetic field treatment was administered to trigger mechanically induced apoptotic cell death of the glioma cells by the rotating SD. We are able to determine that NSC-SD and magnetic field treatment can achieve over 50% glioma cell death when loaded at 50 SD/cell, making this a promising therapeutic for the treatment of glioma.

  8. Overexpression of TIP30 inhibits the growth and invasion of glioma cells

    PubMed Central

    HU, YINGYING; CHEN, FENGSHENG; LIU, FEIYE; LIU, XINHUI; HUANG, NA; CAI, XIAOLI; SUN, YI; LI, AIMIN; LUO, RONGCHENG

    2016-01-01

    Glioma is an aggressive malignancy with limited effective treatment and poor prognosis. Therefore, the identification of novel prognostic markers and effective therapeutic targets is important for the treatment of human glioma. TIP30 is a tumor suppressor involved in the regulation of numerous cellular processes, including tumor cell growth, metastasis, and angiogenesis in various human cancers. The present study investigated whether Tat-interacting protein (TIP)30 was able to regulate tumorigenesis and predict the clinical outcome of patients with glioma. A total of 92 human glioma tissue samples and 10 normal brain tissue samples were examined by immunostaining. The results indicated that the expression levels of TIP30 significantly decreased in glioma tissue samples. as compared with normal brain tissue samples. Furthermore, TIP30 expression was inversely correlated with tumor histological classification, pathological grade, tumor size, and epidermal growth factor receptor (EGFR) expression; however, no association was detected between TIP30 expression and patient age and gender. In addition, patients with positive TIP30 expression exhibited significantly longer median overall survival rates, as compared with those with negative TIP30 expression. In vitro experiments revealed that upregulation of TIP30 expression by lentiviral vector transfection inhibited cell growth and induced cell apoptosis, as determined by MTT assay and Annexin V-fluorescein isothiocyanate staining, respectively. In addition, TIP30 expression markedly attenuated cell migration and invasion, as determined by wound healing and transwell assays. Upregulation of TIP30 expression in glioma cells decreased the expression levels of EGFR and its associated downstream molecules phosphorylated extracellular signal-regulated kinases (ERK) and phosphorylated AKT, as determined by western blot analysis. The results of the present study indicated that TIP30 may suppress oncogenesis and glioma

  9. Glioma-associated endothelial cells show evidence of replicative senescence

    SciTech Connect

    Charalambous, Christiana; Virrey, Jenilyn; Kardosh, Adel; Jabbour, Mark N.; Qazi-Abdullah, Lubna; Pen, Ligaya; Zidovetzki, Raphael; Schoenthal, Axel H.; Chen, Thomas C.; Hofman, Florence M. . E-mail: hofman@usc.edu

    2007-04-01

    The innately programmed process of replicative senescence has been studied extensively with respect to cancer, but primarily from the perspective of tumor cells overcoming this stringent innate barrier and acquiring the capacity for unlimited proliferation. In this study, we focus on the potential role of replicative senescence affecting the non-transformed endothelial cells of the blood vessels within the tumor microenvironment. Based on the well-documented aberrant structural and functional features of blood vessels within solid tumors, we hypothesized that tumor-derived factors may lead to premature replicative senescence in tumor-associated brain endothelial cells (TuBEC). We show here that glioma tissue, but not normal brain tissue, contains cells that express the signature of replicative senescence, senescence-associated {beta}-galactosidase (SA-{beta}-gal), on CD31-positive endothelial cells. Primary cultures of human TuBEC stain for SA-{beta}-gal and exhibit characteristics of replicative senescence, including increased levels of the cell cycle inhibitors p21 and p27, increased resistance to cytotoxic drugs, increased growth factor production, and inability to proliferate. These data provide the first demonstration that tumor-derived brain endothelial cells may have reached an end-stage of differentiation known as replicative senescence and underscore the need for anti-angiogenic therapies to target this unique tumor-associated endothelial cell population.

  10. Saw Palmetto Extract Inhibits Metastasis and Antiangiogenesis through STAT3 Signal Pathway in Glioma Cell.

    PubMed

    Ding, Hong; Shen, Jinglian; Yang, Yang; Che, Yuqin

    2015-01-01

    Signal transducer and activator of transcription factor 3 (STAT3) plays an important role in the proliferation and angiogenesis in human glioma. Previous research indicated that saw palmetto extract markedly inhibited the proliferation of human glioma cells through STAT3 signal pathway. But its effect on tumor metastasis and antiangiogenesis is not clear. This study is to further clear the impact of saw palmetto extract on glioma cell metastasis, antiangiogenesis, and its mechanism. TUNEL assay indicated that the apoptotic cells in the saw palmetto treated group are higher than that in the control group (p < 0.05). The apoptosis related protein is detected and the results revealed that saw palmetto extract inhibits the proliferation of human glioma. Meanwhile pSTAT3 is lower in the experimental group and CD34 is also inhibited in the saw palmetto treated group. This means that saw palmetto extract could inhibit the angiogenesis in glioma. We found that saw palmetto extract was an important phytotherapeutic drug against the human glioma through STAT3 signal pathway. Saw palmetto extract may be useful as an adjunctive therapeutic agent for treatment of individuals with glioma and other types of cancer in which STAT3 signaling is activated.

  11. Saw Palmetto Extract Inhibits Metastasis and Antiangiogenesis through STAT3 Signal Pathway in Glioma Cell

    PubMed Central

    Ding, Hong; Shen, Jinglian; Yang, Yang; Che, Yuqin

    2015-01-01

    Signal transducer and activator of transcription factor 3 (STAT3) plays an important role in the proliferation and angiogenesis in human glioma. Previous research indicated that saw palmetto extract markedly inhibited the proliferation of human glioma cells through STAT3 signal pathway. But its effect on tumor metastasis and antiangiogenesis is not clear. This study is to further clear the impact of saw palmetto extract on glioma cell metastasis, antiangiogenesis, and its mechanism. TUNEL assay indicated that the apoptotic cells in the saw palmetto treated group are higher than that in the control group (p < 0.05). The apoptosis related protein is detected and the results revealed that saw palmetto extract inhibits the proliferation of human glioma. Meanwhile pSTAT3 is lower in the experimental group and CD34 is also inhibited in the saw palmetto treated group. This means that saw palmetto extract could inhibit the angiogenesis in glioma. We found that saw palmetto extract was an important phytotherapeutic drug against the human glioma through STAT3 signal pathway. Saw palmetto extract may be useful as an adjunctive therapeutic agent for treatment of individuals with glioma and other types of cancer in which STAT3 signaling is activated. PMID:26788112

  12. Dobesilate diminishes activation of the mitogen - activated protein kinase ERK1/2 in glioma cells

    PubMed Central

    Cuevas, P; Diaz-González, Diana; Garcia-Martin-Córdova, C; Sánchez, I; Lozano, Rosa Maria; Giménez-Gallego, G; Dujovny, M

    2006-01-01

    Fibroblast growth factors (FGFs) and their receptors, regularly expressed at high levels in gliomas, are further upregulated during the transition of the tumor from low- to high-grade malignancy, and are essential for glioma progression. FGFs induce upregulation of the mitogen-activated protein kinase (MAPK) signaling cascade in cultured glioma cells, which suggests that MAPK pathway participates in the FGF-dependent glioma development. Recently, it has been shown that dobesilate, an inhibitor of FGF mitogenic activity, shows antiproliferative and proapoptotic activities in glioma cell cultures. Accordingly, it should be expected this new synthetic FGF inhibitor to affect the activation levels of MAPK. Here we report that immunocytochemical and Western blot data unequivocally show that treatment of cell cultures with dobesilate causes a significant decrease of the intracellular levels of ERK1/2 activation, one of the components of the MAPK signalling cascade. This finding supports an important role for dobesilate in glioma growth, suggesting that dobesilate should be a treatment to be born in mind for glioma management. PMID:16563234

  13. Effects of glucocorticoids on glioma cells in culture. Minireview on cancer research.

    PubMed

    Freshney, R I

    1984-01-01

    In vitro studies have shown that glucocorticoids have a cytostatic effect on glioma cells at high cell densities but enhance cell survival and proliferation at low cell densities. The cytostatic effect is not cytotoxic and may be mediated via a membrane modification altering cell-cell interaction. Cell interaction is also implicated in differentiation in glial cells and the inducing effect of glucocorticoids may be mediated in part by their effect on cell interaction. Induction of differentiation by glucocorticoids is accompanied by a reduction in malignancy-associated properties and the possibility has emerged that glucocorticoids may be an essential component in attempts to modify the malignant behaviour of glioma cells.

  14. The fruits of Maclura pomifera extracts inhibits glioma stem-like cell growth and invasion.

    PubMed

    Zhao, Dan; Yao, Chengyun; Chen, Xiaobing; Xia, Hongping; Zhang, Li; Liu, Huixiang; Jiang, Xiaochun; Dai, Yi; Liu, Jun

    2013-10-01

    Glioma is the most common primary intracranial tumour. Recently, growing evidence showed that glioma possesses stem-like cells, which are thought to be chemo- and radio-resistant and believed to contribute to the poor clinical outcomes of these tumours. In this study, we found that stem-like glioma cells (CD133+) were significantly increased in neurosphere cells, which are highly invasive and resistant to multiple chemotherapeutic agents. From our natural products library, we screened 48 natural products and found one compound, Pomiferin, which was of particular interest. Our results showed that Pomiferin could inhibit cell viability, CD133+ cell population, sphere formation, and invasion ability of glioma neurosphere cells. We also found that multiple stemness-associated genes (BIM1, Nestin, and Nanog) were down-regulated by Pomiferin treatment of glioma neurosphere cells. Taken together, our results suggest that Pomiferin could kill the cancer stem-like cells in glioma and may serve as a potential therapeutic agent in the future.

  15. Epigenetic regulation of human hedgehog interacting protein in glioma cell lines and primary tumor samples

    PubMed Central

    Shahi, Mehdi H.; Zazpe, Idoya; Afzal, Mohammad; Sinha, Subrata; Rebhun, Robert B.; Meléndez, Bárbara; Rey, Juan A.

    2016-01-01

    Glioma constitutes one of the most common groups of brain tumors, and its prognosis is influenced by different genetic and epigenetic modulations. In this study, we demonstrated low or no expression of hedgehog interacting protein (HHIP) in most of the cell lines and primary glioma tumor samples. We further proceeded to promoter methylation study of this gene in the same cell lines and primary tumor samples and found 87 % (7/8) HHIP methylation in glioblastoma cell lines and 75 % (33/44) in primary tumor samples. These methylation pattern correlates with low or unexpressed HHIP in both cell lines and primary tumor samples. Our results suggest the possibility of epigenetic regulation of this gene in glioma, similarly to medulloblastoma, gastric, hepatic, and pancreatic cancers. Also, HHIP might be a diagnostic or prognostic marker in glioma and help to the detection of these tumors in early stages of disease. PMID:25416442

  16. CD44 promotes the migration of bone marrow-derived mesenchymal stem cells toward glioma

    PubMed Central

    YIN, QIANG; ZHOU, YANG-YANG; WANG, PENG; MA, LI; LI, PENG; WANG, XIAO-GUANG; SHE, CHUN-HUA; LI, WEN-LIANG

    2016-01-01

    Previous in vivo and in vitro studies have shown that human mesenchymal stem cells (MSCs) exhibit tropism for gliomas. However, the mechanism underlying this directed migration remains unclear. The aim of the present study was to investigate the possible mechanism underlying platelet-derived growth factor-BB (PDGF-BB)-induced chemotactic migration of bone marrow-derived MSCs (BMSCs) toward glioma. Rat glioma C6 cell-conditioned medium was utilized to evaluate the chemotactic response of BMSCs toward glioma using an in vitro migration assay. Recombinant rat PDGF-BB was added to C6 cell-conditioned medium to assess its effect on the tropism of BMSCs. The effect of PDGF-BB on the expression levels of cluster of differentiation (CD)44 in BMSCs was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence assays. The results revealed that chemotactic migration was induced in BMSCs by rat glioma C6 cell-conditioned medium, which was enhanced by PDGF-BB treatment in a dose-dependent manner. Furthermore, RT-PCR and immunofluorescence assays showed that CD44 expression was upregulated in BMSCs following treatment with 40 ng/ml PDGF-BB for 12 h. Additionally, 3-h pretreatment with the anti-CD44 neutralizing antibody OX-50 was observed to attenuate the tropism of BMSCs toward glioma in the presence or absence of PDGF-BB. The results of the present study indicate that CD44 mediates the tropism of BMSCs toward glioma, and PDGF-BB promotes the migration of BMSCs toward glioma via the upregulation of CD44 expression in BMSCs. These findings suggest CD44 inhibition may be a potential therapeutic target for the treatment of glioma. PMID:27073479

  17. Suppression of HIV-1 Infectivity by Human Glioma Cells.

    PubMed

    Hoque, Sheikh Ariful; Tanaka, Atsushi; Islam, Salequl; Ahsan, Gias Uddin; Jinno-Oue, Atsushi; Hoshino, Hiroo

    2016-05-01

    HIV-1 infection to the central nervous system (CNS) is very common in AIDS patients. The predominant cell types infected in the brain are monocytes and macrophages, which are surrounded by several HIV-1-resistant cell types, such as astrocytes, oligodendrocytes, neurons, and microvascular cells. The effect of these HIV-1-resistant cells on HIV-1 infection is largely unknown. In this study, we examined the stability of HIV-1 cultured with several human glioblastoma cell lines, for example, NP-2, U87MG, T98G, and A172, to determine whether these HIV-1-resistant brain cells could enhance or suppress HIV-1 infection and thus modulate HIV-1 infection in the CNS. The HIV-1 titer was determined using the MAGIC-5A indicator cell line as well as naturally occurring CD4(+) T cells. We found that the stability of HIV-1 incubated with NP-2 or U87MG cells at 37°C was significantly shorter (half-life, 2.5-4 h) compared to that of HIV-1 incubated with T98G or A172 cells or in culture medium without cells (half-life, 8-18 h). The spent culture media (SCM) of NP-2 and U87MG cells had the ability to suppress both R5- and X4-HIV-1 infection by inhibiting HIV-1 attachment to target cells. This inhibitory effect was eliminated by the treatment of the SCM with chondroitinase ABC but not heparinase, suggesting that the inhibitory factor(s) secreted by NP-2 and U87MG cells was chiefly mediated by chondroitin sulfate (CS) or CS-like moiety. Thus, this study reveals that some but not all glioma cells secrete inhibitory molecules to HIV-1 infection that may contribute in lowering HIV-1 infection in the CNS in vivo.

  18. Autologous glioma cell vaccine admixed with interleukin-4 gene transfected fibroblasts in the treatment of patients with malignant gliomas

    PubMed Central

    Okada, Hideho; Lieberman, Frank S; Walter, Kevin A; Lunsford, L Dade; Kondziolka, Douglas S; Bejjani, Ghassan K; Hamilton, Ronald L; Torres-Trejo, Alejandro; Kalinski, Pawel; Cai, Quan; Mabold, Jennifer L; Edington, Howard D; Butterfield, Lisa H; Whiteside, Theresa L; Potter, Douglas M; Schold, S Clifford; Pollack, Ian F

    2007-01-01

    Background The prognosis for malignant gliomas remains dismal. We addressed the safety, feasibility and preliminary clinical activity of the vaccinations using autologous glioma cells and interleukin (IL)-4 gene transfected fibroblasts. Methods In University of Pittsburgh Cancer Institute (UPCI) protocol 95-033, adult participants with recurrent glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA) received gross total resection (GTR) of the recurrent tumors, followed by two vaccinations with autologous fibroblasts retrovirally transfected with TFG-IL4-Neo-TK vector admixed with irradiated autologous glioma cells. In UPCI 99-111, adult participants with newly diagnosed GBM or AA, following GTR and radiation therapy, received two intradermal vaccinations with the TFG-IL4-Neo-TK-transfected fibroblasts admixed with type-1 dendritic cells (DC) loaded with autologous tumor lysate. The participants were evaluated for occurrence of adverse events, immune response, and clinical response by radiological imaging. Results and Discussion In UPCI 95-033, only 2 of 6 participants received the vaccinations. Four other participants were withdrawn from the trial because of tumor progression prior to production of the cellular vaccine. However, both participants who received two vaccinations demonstrated encouraging immunological and clinical responses. Biopsies from the local vaccine sites from one participant displayed IL-4 dose-dependent infiltration of CD4+ as well as CD8+ T cells. Interferon (IFN)-γ Enzyme-Linked Immuno-SPOT (ELISPOT) assay in another human leukocyte antigen (HLA)-A2+ participant demonstrated systemic T-cell responses against an HLA-A2-restricted glioma-associated antigen (GAA) epitope EphA2883–891. Moreover, both participants demonstrated clinical and radiological improvement with no evidence of allergic encephalitis, although both participants eventually succumbed with the tumor recurrence. In 99-111, 5 of 6 enrolled participants received scheduled

  19. Culture and characteristics of hormone-responsive neuroblastoma x glioma hybrid cells

    SciTech Connect

    Hamprecht, B.; Glaser, T.; Reiser, G.; Bayer, E.; Propst, F.

    1985-01-01

    Neuroblastoma x glioma hybrid cells were generated by cell fusion of the 6-thioguanine-resistant clonal mouse neuroblastoma cells and the bromodeoxyuridine-resistant rat glioma cells, selection, and cloning. Every characteristics generally ascribed to neurons has been observed with the hybrid cells. The paper explores the morphological differentiation of hybrid cells, procedures for testing the hormonal regulation of intracellular levels of cyclic, (/sup 3/H)AMP in hybrid cells, hormonal regulation of adenylate cyclase in homogenates of hyrbid cells, intracellular levels of cyclic GMP, and uptake of guanidinium ions in hybrid cells.

  20. Anti-EGFR function of EFEMP1 in glioma cells and patient prognosis

    PubMed Central

    Hu, Yuanjie; Gao, Hengjun; Vo, Christopher; Ke, Chao; Pan, Francine; Yu, Liping; Siegel, Eric; Hess, Kenneth R.; Linskey, Mark E.; Zhou, Yi-Hong

    2014-01-01

    EGFR is one of the key oncogenes subjected to targeted therapy for several cancers, as it is known to be amplified and/or mutated in up to 40% of malignant gliomas. EFEMP1, a fibulin-like extracellular protein, exerts both tumor suppressive and oncogenic effects in various cancers and glioma cell models. Although EFEMP1's anti-cancer activity has most commonly been attributed to its anti-angiogenic effects, we showed for gliomas that EFEMP1's binding to EGFR accounts for its suppression of the intracranial tumorigenicity of glioma cells expressing high levels of EGFR. In gliomas where EFEMP1 expression, and thus the anti-EGFR effect of EFEMP1, was suppressed, heightened levels of EGFR expression were associated with unfavorable patient outcomes in prognostic models. Results from the current study clearly demonstrate the impact that the anti-EGFR function of EFEMP1 has on the expression of EGFR and patient prognosis. A glioma prognostic model also suggests EFEMP1's context-dependent oncogenic function in gliomas expressing low levels of EGFR. Hence the level of EFEMP1 expression may have a predictive value for choosing patients for anti-EGFR therapy. PMID:25594013

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

    PubMed

    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.

  2. Lipoprotein lipase and phospholipid transfer protein overexpression in human glioma cells and their effect on cell growth, apoptosis, and migration.

    PubMed

    Dong, Weijiang; Gong, Huilin; Zhang, Guanjun; Vuletic, Simona; Albers, John; Zhang, Jiaojiao; Liang, Hua; Sui, Yanxia; Zheng, Jin

    2017-01-01

    Glioma is one of the common tumors in brain. The expression level of lipoprotein lipase (LPL) or phospholipid transfer protein (PLTP) may influence glioma progression and its relationship with clinical and pathological parameters. The clinical significance of LPL or PLTP expression in glioma has not been established. In the present study, the LPL and PLTP levels in glioma tumors were investigated and the relationship between the LPL and PLTP level and the grade of malignant glioma was analyzed, with the aim to provide new ideas for the diagnosis and treatment of gliomas in clinical and basic research settings. LPL and PLTP mRNA and protein levels were significantly higher in Grade IV glioma than those in the lower grade tumors (P < 0.01). Double immunofluorescent staining showed that the levels of LPL and PLTP were significantly associated with the pathological grade of glioma (P = 0.005). The levels of LPL and PLTP were increased with the shortened survival of glioma patients (P < 0.001). Knockdown of LPL and PLTP led to decreased cell growth and migration but increased apoptosis in vitro Additionally, cell cycle-related cyclins and their partners were found to be down-regulated while cyclin-dependent kinase inhibitors p16, p21, and Rb were up-regulated. Furthermore, knockdown of LPL or PLTP resulted in the up-regulation of pro-apoptotic molecules and the down-regulation of anti-apoptotic molecules. Ablation of LPL or PLTP in U251 cells resulted in the down-regulation of epithelial mesenchymal transition markers and invasion molecules matrix metalloproteinases. LPL and PLTP appear to be novel glioma-associated proteins and play a role in the progression of human glioma.

  3. Extracellular electrical recording of pH-triggered bursts in C6 glioma cell populations

    PubMed Central

    Rocha, Paulo R. F.; Medeiros, Maria C. R.; Kintzel, Ulrike; Vogt, Johannes; Araújo, Inês M.; Mestre, Ana L. G.; Mailänder, Volker; Schlett, Paul; Dröge, Melanie; Schneider, Leonid; Biscarini, Fabio; de Leeuw, Dago M.; Gomes, Henrique L.

    2016-01-01

    Glioma patients often suffer from epileptic seizures because of the tumor’s impact on the brain physiology. Using the rat glioma cell line C6 as a model system, we performed long-term live recordings of the electrical activity of glioma populations in an ultrasensitive detection method. The transducer exploits large-area electrodes that maximize double-layer capacitance, thus increasing the sensitivity. This strategy allowed us to record glioma electrical activity. We show that although glioma cells are nonelectrogenic, they display a remarkable electrical burst activity in time. The low-frequency current noise after cell adhesion is dominated by the flow of Na+ ions through voltage-gated ion channels. However, after an incubation period of many hours, the current noise markedly increased. This electric bursting phenomenon was not associated with apoptosis because the cells were viable and proliferative during the period of increased electric activity. We detected a rapid cell culture medium acidification accompanying this event. By using specific inhibitors, we showed that the electrical bursting activity was prompted by extracellular pH changes, which enhanced Na+ ion flux through the psalmotoxin 1–sensitive acid-sensing ion channels. Our model of pH-triggered bursting was unambiguously supported by deliberate, external acidification of the cell culture medium. This unexpected, acidosis-driven electrical activity is likely to directly perturb, in vivo, the functionality of the healthy neuronal network in the vicinity of the tumor bulk and may contribute to seizures in glioma patients. PMID:28028533

  4. Calcium entry via TRPC1 channels activates chloride currents in human glioma cells

    PubMed Central

    Cuddapah, Vishnu Anand; Turner, Kathryn L.; Sontheimer, Harald

    2012-01-01

    Malignant gliomas are highly-invasive brain cancers that carry a dismal prognosis. Recent studies indicate that Cl− channels facilitate glioma cell invasion by promoting hydrodynamic cell shape and volume changes. Here we asked how Cl− channels are regulated in the context of migration. Using patch-clamp recordings we show Cl− currents are activated by physiological increases of [Ca2+]i to 65 and 180 nM. Cl− currents appear to be mediated by ClC-3, a voltage-gated, CaMKII-regulated Cl− channel highly expressed by glioma cells. ClC-3 channels colocalized with TRPC1 on caveolar lipid rafts on glioma cell processes. Using perforated-patch electrophysiological recordings, we demonstrate that inducible knockdown of TRPC1 expression with shRNA significantly inhibited glioma Cl− currents in a Ca2+-dependent fashion, placing Cl− channels under the regulation of Ca2+ entry via TRPC1. In chemotaxis assays epidermal growth factor (EGF)-induced invasion was inhibition by TRPC1 knockdown to the same extent as pharmacological block of Cl− channels. Thus endogenous glioma Cl− channels are regulated by TRPC1. Cl− channels could be an important downstream target of TRPC1 in many other cells types, coupling elevations in [Ca2+]i to the shape and volume changes associated with migrating cells. PMID:23261316

  5. TRAIL conjugated to nanoparticles exhibits increased anti-tumor activities in glioma cells and glioma stem cells in vitro and in vivo

    PubMed Central

    Perlstein, Benny; Finniss, Susan A.; Miller, Cathie; Okhrimenko, Hana; Kazimirsky, Gila; Cazacu, Simona; Lee, Hae Kyung; Lemke, Nancy; Brodie, Shlomit; Umansky, Felix; Rempel, Sandra A.; Rosenblum, Mark; Mikklesen, Tom; Margel, Shlomo; Brodie, Chaya

    2013-01-01

    Glioblastomas (GBM) are characterized by resistance to chemotherapy and radiotherapy, and therefore, alternative therapeutic approaches are needed. TRAIL induces apoptosis in cancer but not in normal cells and is considered to be a promising anti-tumor agent. However, its short in vivo half-life and lack of efficient administration modes are serious impediments to its therapeutic efficacy. Nanoparticles (NP) have been used as effective delivery tools for various anticancer drugs. TRAIL was conjugated to magnetic ferric oxide NP by binding the TRAIL primary amino groups to activated double bonds on the surface of the NP. The effect of NP-TRAIL was examined on the apoptosis of glioma cells and self-renewal of glioma stem cells (GSCs). In addition, the ability of the NP-TRAIL to track U251 cell–derived glioma xenografts and to affect cell apoptosis, tumor volume, and survival among xenografted rats was also examined. Conjugation of TRAIL to NP increased its apoptotic activity against different human glioma cells and GSCs, as compared with free recombinant TRAIL. Combined treatment with NP-TRAIL and γ-radiation or bortezomib sensitized TRAIL-resistant GSCs to NP-TRAIL. Using rhodamine-labeled NP and U251 glioma cell–derived xenografts, we demonstrated that the NP-TRAIL were found in the tumor site and induced a significant increase in glioma cell apoptosis, a decrease in tumor volume, and increased animal survival. In summary, conjugation of TRAIL to NP increased its apoptotic activity both in vitro and in vivo. Therefore, NP-TRAIL represents a targeted anticancer agent with more efficient action for the treatment of GBM and the eradication of GSCs. PMID:23144078

  6. Quercetin derivatives as potent inducers of selective cytotoxicity in glioma cells.

    PubMed

    Dell'Albani, Paola; Di Marco, Barbara; Grasso, Sonia; Rocco, Concetta; Foti, Mario C

    2017-04-01

    Quercetin (Q) is a flavonoid widely distributed in the plant kingdom and well-known for its ability to exert antioxidant, prooxidant and anticarcinogenic activities in several tumor cells. Furthermore, quercetin plays an important role both in the regulation of key elements in cellular signal transduction pathways related to apoptotic cell death, and in cell cycle progression. Several studies have reported of toxic effects of Q against glioma cell lines. In this study, the effects of Q and of some Q-derivatives (acyl esters and bromo-derivatives) on U373-MG and 9L glioma cell lines survival are analyzed. The 24-hour treatment of glioma cells with several concentrations of Q (25, 50 and 100μM) did not cause any cytotoxic effects, while the administration of Q-derivatives, such as acylated and brominated quercetin, caused a sharp increase in cell death. Among all tested derivatives, 3-O-decanoylquercetin 10 manifested the strongest cytotoxic effect at a concentration as low as 25μM both in U373-MG (ca. 40% viability after 24h) and in 9L cells (ca. 20% viability after 24h). The cytotoxic effects of the Q-derivatives 3 and 10-13 were proven to be satisfactorily selective for glioma cells. When Q-derivatives were in fact administered to mouse primary astroglial or human fibroblast cell cultures, a higher cell survival rate (~90-70% and 55-45%, respectively) was observed relative to that detected in glioma cells. These results prove that selective esterification and bromination of Q increase to a great extent the toxicity of this polyphenol against glioma cells, thereby providing a possible new tool for cyto-specific glioma therapy.

  7. Autophagy and the functional roles of Atg5 and beclin-1 in the anti-tumor effects of 3beta androstene 17alpha diol neuro-steroid on malignant glioma cells.

    PubMed

    Graf, Martin R; Jia, Wentao; Johnson, Ross S; Dent, Paul; Mitchell, Clint; Loria, Roger M

    2009-07-01

    In this study, we demonstrate that the anti-tumor activity of the neuro-steroid, 3beta androstene 17alpha diol (17alpha-AED) on malignant glioma cells is mediated by the induction of autophagy. 17alpha-AED can inhibit the proliferation an induce cell death of multiple, unrelated gliomas with an IC(50) between 8 and 25muM. 17alpha-AED treatment induced the formation of autophagosomes and acidic vesicular organelles in human malignant gliomas which was blocked by bafilomycin A1 or 3-methyladenine. Cleavage of microtubule-associated protein-light chain 3 (LC3), an essential step in autophagosome formation, was detected in human malignant glioma cells exposed to 17alpha-AED. In 17alpha-AED treated T98G glioma cells there was an increase in the autophagy related proteins Atg5 and beclin-1. Silencing of ATG5 or beclin-1 with small interfering RNA significantly reduced the incidence of autophagy in 17alpha-AED treated malignant gliomas and attenuated the cytotoxic effects of the neuro-steroid indicating that the induction of autophagy mediates the anti-glioma activity of 17alpha-AED rather than serving as a cyto-protective response. These results demonstrate that 17alpha-AED possesses significant anti-glioma activity when used at pharmacologically relevant concentrations in vitro and the cytotoxic effects are resultant from the induction of autophagy.

  8. Stimulation of the midkine/ALK axis renders glioma cells resistant to cannabinoid antitumoral action

    PubMed Central

    Lorente, M; Torres, S; Salazar, M; Carracedo, A; Hernández-Tiedra, S; Rodríguez-Fornés, F; García-Taboada, E; Meléndez, B; Mollejo, M; Campos-Martín, Y; Lakatosh, S A; Barcia, J; Guzmán, M; Velasco, G

    2011-01-01

    Identifying the molecular mechanisms responsible for the resistance of gliomas to anticancer treatments is an issue of great therapeutic interest. Δ9-Tetrahydrocannabinol (THC), the major active ingredient of marijuana, and other cannabinoids inhibit tumor growth in animal models of cancer, including glioma, an effect that relies, at least in part, on the stimulation of autophagy-mediated apoptosis in tumor cells. Here, by analyzing the gene expression profile of a large series of human glioma cells with different sensitivity to cannabinoid action, we have identified a subset of genes specifically associated to THC resistance. One of these genes, namely that encoding the growth factor midkine (Mdk), is directly involved in the resistance of glioma cells to cannabinoid treatment. We also show that Mdk mediates its protective effect via the anaplastic lymphoma kinase (ALK) receptor and that Mdk signaling through ALK interferes with cannabinoid-induced autophagic cell death. Furthermore, in vivo Mdk silencing or ALK pharmacological inhibition sensitizes cannabinod-resistant tumors to THC antitumoral action. Altogether, our findings identify Mdk as a pivotal factor involved in the resistance of glioma cells to THC pro-autophagic and antitumoral action, and suggest that selective targeting of the Mdk/ALK axis could help to improve the efficacy of antitumoral therapies for gliomas. PMID:21233844

  9. Products of cells cultured from gliomas. VI. Immunofluorescent, morphometric, and ultrastructural characterization of two different cell types growing from explants of human gliomas.

    PubMed Central

    McKeever, P. E.; Smith, B. H.; Taren, J. A.; Wahl, R. L.; Kornblith, P. L.; Chronwall, B. M.

    1987-01-01

    Explants derived from human gliomas have been characterized with respect to their cellular outgrowth pattern after 1-22 weeks in culture. A mat of cells which were fibronectin (FN)-positive and glial fibrillary acidic protein (GFAP)-negative (hereafter designated FN+ cells) with a polygonal, flat morphology covered the growth substrate in a swirling pattern for a mean diameter of 9.2 mm around FN+ explants. FN+ cells showed ruffled plasmalemma, dilated rough endoplasmic reticulin (RDR), and extracellular filamentous strands. Rare desmosomes were compatible with at most minor leptomeningeal components or differentiation. FN+ cells predominated in six of seven cultures at passage 2, and their features were the same from various high-grade gliomas and gliosarcoma. Around other explants, elongated or stellate cells which were GFAP+ and FN- grew in a netlike pattern with little cell-to-cell contact. These GFAP+ cells surrounded explants at a mean diameter of 2 mm, substantially less than FN+ cells (P less than 0.005), and they grew more slowly than FN+ cells around explants. GFAP+ cells had an area/perimeter ratio which was less than that of FN+ cells. GFAP+ cells contained abundant intracellular filaments, rare desmosomes, and narrow RER cisternae. In mixed explants, GFAP+ cells often grew on top of FN+ cells. Individual cells which stained for both GFAP and FN were evident only from one glioma (8% doubly positive). Cells negative for both proteins resembled FN+ cells morphologically. Frozen sections of original glioma tissue showed FN+ vessel walls and GFAP+ parenchyma. Results are evidence for very early overgrowth of a preexistent FN+ cell type distinct from the GFAP+ parenchymal cell. The features of this distinct cell type are mesenchymal and resemble the proliferating vascular elements of gliomas in situ. The tendency for GFAP+ cells to grow on top of these FN+ cells suggests a feeder layer interaction. More knowledge of the origins and interactions of these two

  10. MicroRNA-217 inhibits cell proliferation and invasion by targeting Runx2 in human glioma

    PubMed Central

    Zhu, Yonggang; Zhao, Hongguang; Feng, Li; Xu, Songbai

    2016-01-01

    MircroRNA-217 (miR-217) has been showed to involve in the initiation and development of human cancers, and is recognize as a tumor suppressor miRNA in several tumors. However, the clinical significance and its underlying role in human glioma remain unclear. Herein, we found that the expression of miR-217 was significantly down-regulated in glioma tissues as compared with adjacent normal brain tissues. Clinical association analysis disclosed that low-expression of miR-217 was evidently negative associated with advanced tumor stage (grade III + IV) in glioma. Further function assays showed that miR-217 inhibited proliferation, colony formation, invasion and migration of glioma cells. Notably, runt-related transcription factors 2 (Runx2) was identified as a functional target of miR-217 in glioma. Furthermore, an inverse correlation between miR-217 and Runx2 expression was observed in glioma tissues. Downregulation of Runx2 has similar with inhibition effect of overexpression of miR-217, and upregulation of Runx2 reversed the effects of overexpressing of miR-217. Taken together, these results suggest a critical role of miR-217 in suppressing proliferation, migration, and invasion of glioma by targeting Runx2. PMID:27186274

  11. microRNA-153 Targets mTORC2 Component Rictor to Inhibit Glioma Cells

    PubMed Central

    Cui, Yan; Zhao, Jizong; Yi, Lei; Jiang, Yugang

    2016-01-01

    Rictor upregulation and mTORC complex 2 (mTORC2) over-activation participate in glioma cell progression, yet the underling mechanisms are not known. We here identified microRNA-153 (miR-153) as a potential anti-Rictor miRNA, which was downregulated in multiple human glioma tissues and glioma cell lines (U87MG, T98G, U373MG and U251MG). miR-153 downregulation was correlated with Rictor (mRNA and protein) upregulation and p-Akt Ser473 (the mTORC2 indicator) over-activation in the glioma tissues and cells. Our in vitro evidences suggested that Rictor could be one primary target of miR-153 in glioma cells. Exogenous overexpression of miR-153 downregulated Rictor (mRNA and protein) and decreased p-Akt Ser473 in U87MG cells, leading to significant growth inhibition and apoptosis activation. Notably, U87MG cells with Rictor shRNA knockdown showed similar phenotypes of cells with miR-153 overexpression. More importantly, in Rictor-silenced U87MG cells, miR-153 expression failed to further affect cell growth nor apoptosis. In vivo, we showed that miR-153 overexpression dramatically inhibited U87MG tumor growth in nude mice. Together, these results suggest that miR-153 downregulation could be one important reason of Rictor upregulation and mTORC2 over-activation in glioma cells. Further, miR-153-induced anti-glioma cell activity is possibly via downregulating Rictor. PMID:27295037

  12. Long noncoding RNA FTX is upregulated in gliomas and promotes proliferation and invasion of glioma cells by negatively regulating miR-342-3p.

    PubMed

    Zhang, Weiguang; Bi, Yunke; Li, Jianhua; Peng, Fei; Li, Hui; Li, Chenguang; Wang, Laizang; Ren, Fubin; Xie, Chen; Wang, Pengwei; Liang, Weiwei; Wang, Zhi; Zhu, Dan

    2017-04-01

    Gliomas remain a major public health challenge, posing a high risk for brain tumor-related morbidity and mortality. However, the mechanisms that drive the development of gliomas remain largely unknown. Emerging evidence has shown that long noncoding RNAs are key factors in glioma pathogenesis. qRT-PCR analysis was used to assess the expression of FTX and miR-342-3p in the different stages of gliomas in tissues. Bioinformatics tool DIANA and TargetSCan were used to predict the targets of FTX and miR-342-3p, respectively. Pearson's correlation analysis was performed to test the correlation between the expression levels of FTX, miR-342-3p, and astrocyte-elevated gene-1 (AEG-1). To examine the role of FTX in regulating proliferation and invasion of glioma cells, specific siRNA was used to knockdown FTX, and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and transwell assays were performed. Furthermore, rescue experiments were performed to further confirm the regulation of miR-342-3p by FTX. We then found that the expression of FTX and miR-342-3p was associated with progression of gliomas. FTX directly inhibited the expression of miR-342-3p, which subsequently regulates the expression of AEG-1. Collectively, FTX is critical for proliferation and invasion of glioma cells by regulating miR-342-3p and AEG-1. Our findings indicate that FTX and miR-342-3p may serve as a biomarker of glioma diagnosis, and offer potential novel therapeutic targets of treatment of gliomas.

  13. Ets Factors Regulate Neural Stem Cell Depletion and Gliogenesis in Ras Pathway Glioma.

    PubMed

    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.

  14. Molecular subtypes, stem cells and heterogeneity: Implications for personalised therapy in glioma.

    PubMed

    Morokoff, Andrew; Ng, Wayne; Gogos, Andrew; Kaye, Andrew H

    2015-08-01

    We discuss a number of recent developments that have led to new concepts regarding the biology of gliomas. Collective tissue banking, large-scale genomic, transcriptomic and methylomic expression profiling, and discoveries such as isocitrate dehydrogenase gene mutation and the C-phosphate-G island methylation phenotype have improved glioma classification schemes. Furthermore, the discovery of glioma stem cells has both enhanced and complicated our understanding. Gene signatures describing a proneural versus mesenchymal subtype within glioblastoma multiforme is reflected in both parental tumour as well as glioma stem cells and correlates with differential prognosis and response to radiation and chemotherapy. Finally, we discuss how these factors integrate with the known heterogeneity within brain cancers and the implications of this for the development of personalised therapy.

  15. The tricyclic antidepressant imipramine induces autophagic cell death in U-87MG glioma cells.

    PubMed

    Jeon, Seung-Hyun; Kim, Se Hyun; Kim, Yeni; Kim, Yong Sik; Lim, Yoongho; Lee, Young Han; Shin, Soon Young

    2011-09-23

    In this study, we investigated the antitumor effects of the tricyclic antidepressant 3-(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)-N,N-dimethylpropan-1-amine (imipramine) on glioma cells. We found that exposure of U-87MG cells to imipramine resulted in the inhibition of PI3K/Akt/mTOR signaling, reduction of clonogenicity, and induction of cell death. Imipramine stimulated the formation of acidic vesicular organelles, the conversion of LC3-I to LC3-II, and the redistribution of LC3 to autophagosomes, suggesting that it stimulates the progression of autophagy. It did not, however, induce apoptosis. We further showed that knockdown of Beclin-1 using siRNA abrogated imipramine-induced cell death. These results suggest that imipramine exerts antitumor effects on PTEN-null U-87MG human glioma cells by inhibiting PI3K/Akt/mTOR signaling and by inducing autophagic cell death.

  16. The involvement of heparan sulfate proteoglycans in stem cell differentiation and in malignant glioma

    NASA Astrophysics Data System (ADS)

    Kundu, Soumi; Xiong, Anqi; Forsberg-Nilsson, Karin

    2016-04-01

    Heparan sulfate (HS) proteoglycans (HSPG) are major components of the extracellular matrix. They interact with a plethora of macromolecules that are of physiological importance. The pattern of sulfation of the HS chain determines the specificity of these interactions. The enzymes that synthesize and degrade HS are thus key regulators of processes ranging from embryonic development to tissue homeostasis and tumor development. Formation of the nervous system is also critically dependent on appropriate HSPGs as shown by several studies on the role of HS in neural induction from embryonic stem cells. High-grade glioma is the most common primary malignant brain tumor among adults, and the prognosis is poor. Neural and glioma stem cells share several traits, including sustained proliferation and highly efficient migration in the brain. There are also similarities between the neurogenic niche where adult neural stem cells reside and the tumorigenic niche, including their interactions with components of the extracellular matrix (ECM). The levels of many of these components, for example HSPGs and enzymes involved in the biosynthesis and modification of HS are attenuated in gliomas. In this paper, HS regulation of pathways involved in neural differentiation and how these may be of importance for brain development are discussed. The literature suggesting that modifications of HS could regulate glioma growth and invasion is reviewed. Targeting the invasiveness of glioma cells by modulating HS may improve upon present therapeutic options, which only marginally enhance the survival of glioma patients.

  17. Decitabine Treatment of Glioma-Initiating Cells Enhances Immune Recognition and Killing

    PubMed Central

    Riccadonna, Cristina; Yacoub Maroun, Céline; Vuillefroy de Silly, Romain; Boehler, Margaux; Calvo Tardón, Marta; Jueliger, Simone; Taverna, Pietro; Barba, Leticia; Marinari, Eliana; Pellegatta, Serena; Bassoy, Esen Yonca; Martinvalet, Denis; Dietrich, Pierre-Yves; Walker, Paul R.

    2016-01-01

    Malignant gliomas are aggressive brain tumours with very poor prognosis. The majority of glioma cells are differentiated (glioma-differentiated cells: GDCs), whereas the smaller population (glioma-initiating cells, GICs) is undifferentiated and resistant to conventional therapies. Therefore, to better target this pool of heterogeneous cells, a combination of diverse therapeutic approaches is envisaged. Here we investigated whether the immunosensitising properties of the hypomethylating agent decitabine can be extended to GICs. Using the murine GL261 cell line, we demonstrate that decitabine augments the expression of the death receptor FAS both on GDCs and GICs. Interestingly, it had a higher impact on GICs and correlated with an enhanced sensitivity to FASL-mediated cell death. Moreover, the expression of other critical molecules involved in cognate recognition by cytotoxic T lymphocytes, MHCI and ICAM-1, was upregulated by decitabine treatment. Consequently, T-cell mediated killing of both GDCs and GICs was enhanced, as was T cell proliferation after reactivation. Overall, although GICs are described to resist classical therapies, our study shows that hypomethylating agents have the potential to enhance glioma cell recognition and subsequent destruction by immune cells, regardless of their differentiation status. These results support the development of combinatorial treatment modalities including epigenetic modulation together with immunotherapy in order to treat heterogenous malignancies such as glioblastoma. PMID:27579489

  18. Isolation and Flow Cytometric Analysis of Glioma-infiltrating Peripheral Blood Mononuclear Cells

    PubMed Central

    Baker, Gregory J.; Castro, Maria G.; Lowenstein, Pedro R.

    2016-01-01

    Our laboratory has recently demonstrated that natural killer (NK) cells are capable of eradicating orthotopically implanted mouse GL26 and rat CNS-1 malignant gliomas soon after intracranial engraftment if the cancer cells are rendered deficient in their expression of the β-galactoside-binding lectin galectin-1 (gal-1). More recent work now shows that a population of Gr-1+/CD11b+ myeloid cells is critical to this effect. To better understand the mechanisms by which NK and myeloid cells cooperate to confer gal-1-deficient tumor rejection we have developed a comprehensive protocol for the isolation and analysis of glioma-infiltrating peripheral blood mononuclear cells (PBMC). The method is demonstrated here by comparing PBMC infiltration into the tumor microenvironment of gal-1-expressing GL26 gliomas with those rendered gal-1-deficient via shRNA knockdown. The protocol begins with a description of how to culture and prepare GL26 cells for inoculation into the syngeneic C57BL/6J mouse brain. It then explains the steps involved in the isolation and flow cytometric analysis of glioma-infiltrating PBMCs from the early brain tumor microenvironment. The method is adaptable to a number of in vivo experimental designs in which temporal data on immune infiltration into the brain is required. The method is sensitive and highly reproducible, as glioma-infiltrating PBMCs can be isolated from intracranial tumors as soon as 24 hr post-tumor engraftment with similar cell counts observed from time point matched tumors throughout independent experiments. A single experimentalist can perform the method from brain harvesting to flow cytometric analysis of glioma-infiltrating PBMCs in roughly 4–6 hr depending on the number of samples to be analyzed. Alternative glioma models and/or cell-specific detection antibodies may also be used at the experimentalists’ discretion to assess the infiltration of several other immune cell types of interest without the need for alterations to the

  19. IKBKE is over-expressed in glioma and contributes to resistance of glioma cells to apoptosis via activating NF-κB.

    PubMed

    Guan, Hongyu; Zhang, Heng; Cai, Junchao; Wu, Jueheng; Yuan, Jie; Li, Jun; Huang, Zhengsong; Li, Mengfeng

    2011-02-01

    IκB kinase-ε (IKBKE), a member of the IκB kinase (IKK) family, has been identified as an oncogenic protein and found to be up-regulated in breast cancer, ovarian cancer and prostate cancer. Nonetheless, the expression status and functional significance of IKBKE in human glioma remain unexplored. For the first time, we have demonstrated that mRNA and protein levels of IKBKE were robustly up-regulated in glioma cell lines and human primary glioma tissues. Immunohistochemistry analysis revealed that 53.5% (38/71) paraffin-embedded archived glioma specimens exhibited high levels of IKBKE expression. Intriguingly, there was no significant difference in IKBKE expression among different grades of glioma. To understand the biological function of IKBKE in the development and progression of human glioma, glioma cells lines ectopically over-expressing IKBKE were established and tested for their responsiveness to apoptotic inducers. Our data showed that IKBKE over-expression inhibited cell apoptosis induced by UV irradiation or adriamycin and, in contrast, shRNAi-mediated suppression of IKBKE increased the sensitivity of glioma cells to the apoptotic inducers. Importantly, we found that up-regulated IKBKE could induce the expression of Bcl-2 through activating NF-κB signalling, and that, specifically, we identified IκB as a critical component for this signalling cascade. The current study suggests that up-regulation of IKBKE may represent an important molecular hallmark that is biologically and clinically relevant to the development and progression, as well as the chemo- and radio-resistance, of the disease.

  20. CacyBP/SIP protein is important for the proliferation of human glioma cells.

    PubMed

    Shi, Hengliang; Gao, Yong; Tang, Yuan; Wu, Yuxuan; Gong, Hui; Du, Jin; Zheng, Bao; Hu, Jinxia; Shi, Qiong; Yu, Rutong

    2014-04-01

    Recently, calcyclin-binding protein or Siah-1-interacting protein (CacyBP/SIP), a component of a novel ubiquitinylation pathway, could regulate the β-catenin degradation (Fukushima et al., Immunity 2006, 24, 29-39). However, the potential role of CacyBP/SIP itself in human glioma cells has not been clarified. Here, we found that CacyBP/SIP was expressed highly in human glioma tissues. Silencing of CacyBP/SIP by short-hairpin RNA severely suppressed the proliferation of human glioma cell U251, which was at least partly mediated by downregulation of phospho-Akt (p-Akt) and phospho-β-catenin (p-β-catenin) as well as upregulation of p53 and p21. Furthermore, overexpression of CacyBP/SIP obviously promoted the proliferation of human glioma U251, which exhibited the exactly contrary trend in the expression of p-Akt, p-β-catenin, p53, and p21. Taken together, these findings suggest that CacyBP/SIP plays important roles in the proliferation of human glioma cell which might be involved in the development of human glioma.

  1. TRPM7 channels regulate glioma stem cell through STAT3 and Notch signaling pathways.

    PubMed

    Liu, Mingli; Inoue, Koichi; Leng, Tiandong; Guo, Shanchun; Xiong, Zhi-gang

    2014-12-01

    Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in adults with median survival time of 14.6 months. A small fraction of cancer stem cells (CSC) initiate and maintain tumors thus driving glioma tumorigenesis and being responsible for resistance to classical chemo- and radio-therapies. It is desirable to identify signaling pathways related to CSC to develop novel therapies to selectively target them. Transient receptor potential cation channel, subfamily M, member 7, also known as TRPM7 is a ubiquitous, Ca(2+) and Mg(2+) permeable ion channels that are special in being both an ion channel and a serine/threonine kinase. In studies of glioma cells silenced for TRPM7, we demonstrated that Notch (Notch1, JAG1, Hey2, and Survivin) and STAT3 pathways are down regulated in glioma cells grown in monolayer. Furthermore, phospho-STAT3, Notch target genes and CSC markers (ALDH1 and CD133) were significantly higher in spheroid glioma CSCs when compared with monolayer cultures. The results further show that tyrosine-phosphorylated STAT3 binds and activates the ALDH1 promoters in glioma cells. We found that TRMP7-induced upregulation of ALDH1 expression is associated with increases in ALDH1 activity and is detectable in stem-like cells when expanded as spheroid CSCs. Finally, TRPM7 promotes proliferation, migration and invasion of glioma cells. These demonstrate that TRPM7 activates JAK2/STAT3 and/or Notch signaling pathways and leads to increased cell proliferation and migration. These findings for the first time demonstrates that TRPM7 (1) activates a previously unrecognized STAT3→ALDH1 pathway, and (2) promotes the induction of ALDH1 activity in glioma cells.

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

    PubMed

    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.

  3. Inhibition of proliferation and induction of differentiation of glioma cells with Datura stramonium agglutinin.

    PubMed

    Sasaki, T; Yamazaki, K; Yamori, T; Endo, T

    2002-10-07

    We found that a lectin, Datura stramonium agglutinin, induced irreversible differentiation in C6 glioma cells. The differentiated cells had long processes, a low rate of proliferation and a high content of glial fibrillary acidic protein. When the medium was replaced with Datura stramonium agglutinin-free medium after 1 h, cell proliferation continued to be inhibited. Experiments with several other lectins indicated that both recognition of linear N-acetyllactosamine repeats and recognition of multiantennary units of cell-surface glycans were required for the inhibition of C6 proliferation. Proliferation of four human glial tumour cells was also inhibited by Datura stramonium agglutinin. Further, these differentiated human glial tumour cells had long processes and a high content of glial fibrillary acidic protein similar to differentiated C6 glioma cells. Taken together, these observations suggest that Datura stramonium agglutinin may be useful as a new therapy for treating glioma without side effects.

  4. Gene therapy with HSV1-sr39TK/GCV exhibits a stronger therapeutic efficacy than HSV1-TK/GCV in rat C6 glioma cells.

    PubMed

    Li, Lei-qing; Shen, Fang; Xu, Xiao-yan; Zhang, Hong; Yang, Xiao-feng; Liu, Wei-guo

    2013-01-01

    Although the combination of herpes simplex virus type 1 (HSV-1) thymidine kinase (TK) with ganciclovir (GCV) has been shown as a promising suicide gene treatment strategy for glioma, the almost immunodepressive dose of GCV required for its adequate in vivo efficacy has hampered its further clinical application. Therefore, In order to reduce the GCV dose required, we aim to compare the therapeutic efficacy of HSV1-sr39TK, an HSV1-TK mutant with increased GCV prodrug catalytic activity, with wildtype TK in C6 glioma cells. Accordingly, rat C6 glioma cells were first transfected with pCDNA-TK and pCDNA-sr39TK, respectively, and the gene transfection efficacy was verified by immunocytochemistry and western blot analysis. Then the in vivo sensitivity of these transfected C6-TK and C6-sr39TK cells to GCV was determined by 3-(4,5)-dimethylthiahiazo-(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) colorimetric assay and Hoechst-propidium iodide (PI) staining. Finally, a subcutaneously C6 xenograft tumor model was established in the nude mice to test the in vitro efficacy of TK/GCV gene therapy. Our results showed that, as compared with wildtype TK, HSV1-sr39TK/GCV demonstrated a stronger therapeutic efficacy against C6 glioma both in vitro and in vivo, which, by reducing the required GCV dose, might warrant its future use in the treatment of glioma under clinical setting.

  5. Connexin43 recruits PTEN and Csk to inhibit c-Src activity in glioma cells and astrocytes

    PubMed Central

    González-Sánchez, Ana; Jaraíz-Rodríguez, Myriam; Domínguez-Prieto, Marta; Herrero-González, Sandra; Medina, José M.; Tabernero, Arantxa

    2016-01-01

    Connexin43 (Cx43), the major protein forming gap junctions in astrocytes, is reduced in high-grade gliomas, where its ectopic expression exerts important effects, including the inhibition of the proto-oncogene tyrosine-protein kinase Src (c-Src). In this work we aimed to investigate the mechanism responsible for this effect. The inhibition of c-Src requires phosphorylation at tyrosine 527 mediated by C-terminal Src kinase (Csk) and dephosphorylation at tyrosine 416 mediated by phosphatases, such as phosphatase and tensin homolog (PTEN). Our results showed that the antiproliferative effect of Cx43 is reduced when Csk and PTEN are silenced in glioma cells, suggesting the involvement of both enzymes. Confocal microscopy and immunoprecipitation assays confirmed that Cx43, in addition to c-Src, binds to PTEN and Csk in glioma cells transfected with Cx43 and in astrocytes. Pull-down assays showed that region 266–283 in Cx43 is sufficient to recruit c-Src, PTEN and Csk and to inhibit the oncogenic activity of c-Src. As a result of c-Src inhibition, PTEN was increased with subsequent inactivation of Akt and reduction of proliferation of human glioblastoma stem cells. We conclude that the recruitment of Csk and PTEN to the region between residues 266 and 283 within the C-terminus of Cx43 leads to c-Src inhibition. PMID:27391443

  6. Knockdown of NEAT1 restrained the malignant progression of glioma stem cells by activating microRNA let-7e

    PubMed Central

    Gong, Wei; Zheng, Jian; Liu, Xiaobai; Ma, Jun; Liu, Yunhui; Xue, Yixue

    2016-01-01

    Nuclear paraspeckle assembly transcript 1 (NEAT1), a long non-coding RNA, promotes oncogenesis in various tumors, including human gliomas. Herein, we studied the expression and function of NEAT1 in glioma stem cells (GSCs). Quantitative real-time PCR demonstrated that NEAT1 was upregulated in GSCs. NEAT1 knockdown inhibited GSC cell proliferation, migration and invasion and promoted GSC apoptosis. A potential binding region between NEAT1 and microRNA let-7e was confirmed by dual-luciferase assays. Upregulation of NEAT1 reduced the expression of let-7e, and there was reciprocal repression between NEAT1 and let-7e in an Argonaute 2-dependent manner. Let-7e expression was lower expression in glioblastoma tissues and GSCs than in normal brain tissues and cells. Restoration of let-7e suppressed tumor function by inhibiting proliferation, migration and invasion while promoting apoptosis in GSCs. NEAT1 knockdown and let-7e overexpression both reduced NRAS protein expression. NRAS was identified as a direct target of let-7e and promoted oncogenesis in GSCs. As NEAT1 promoted oncogenesis by downregulating let-7e expression, both of these genes could be considered for application in glioma therapy. PMID:27556696

  7. Nrf2 is required to maintain the self-renewal of glioma stem cells

    PubMed Central

    2013-01-01

    Background Glioblastomas are deadly cancers that display a functional cellular hierarchy maintained by self-renewing glioma stem cells (GSCs). Self-renewal is a complex biological process necessary for maintaining the glioma stem cells. Nuclear factor rythroid 2-related factor 2(Nrf2) plays a significant role in protecting cells from endogenous and exogenous stresses. Nrf2 is a key nuclear transcription factor that regulates antioxidant response element (ARE)-containing genes. Previous studies have demonstrated the significant role of Nrf2 in the proliferation of glioblastoma, and in their resistance to radioactive therapies. We examined the effect of knocking down Nrf2 in GSCs. Methods Nrf2 expression was down-regulated by shRNA transinfected with lentivirus. Expression levels of Nestin, Nrf2, BMI-1, Sox2 and Cyclin E were assessed by western blotting, quantitative polymerase chain reaction (qPCR) and immunohistochemistry analysis. The capacity for self-renewal in vitro was assessed by genesis of colonies. The capacity for self-renewal in vivo was analyzed by tumor genesis of xenografts in nude mice. Results Knockdown of Nrf2 inhibited the proliferation of GSCs, and significantly reduced the expression of BMI-1, Sox2 and CyclinE. Knocking down of Nrf2 changed the cell cycle distribution of GSCs by causing an uncharacteristic increase in the proportion of cells in the G2 phase and a decrease in the proportion of cells in the S phase of the cell cycle. Conclusions Nrf2 is required to maintain the self-renewal of GSCs, and its down-regulation can attenuate the self-renewal of GSCs significantly. PMID:23937621

  8. Ligand modified nanoparticles increases cell uptake, alters endocytosis and elevates glioma distribution and internalization.

    PubMed

    Gao, Huile; Yang, Zhi; Zhang, Shuang; Cao, Shijie; Shen, Shun; Pang, Zhiqing; Jiang, Xinguo

    2013-01-01

    Nanoparticles (NPs) were widely used in drugs/probes delivery for improved disease diagnosis and/or treatment. Targeted delivery to cancer cells is a highly attractive application of NPs. However, few studies have been performed on the targeting mechanisms of these ligand-modified delivery systems. Additional studies are needed to understand the transport of nanoparticles in the cancer site, the interactions between nanoparticles and cancer cells, the intracellular trafficking of nanoparticles within the cancer cells and the subcellular destiny and potential toxicity. Interleukin 13 (IL-13) peptide can specifically bind IL-13Rα2, a receptor that is highly expressed on glioma cells but is expressed at low levels on other normal cells. It was shown that the nanoparticels modification with the IL-13 peptide could improve glioma treatment by selectively increasing cellular uptake, facilitating cell internalization, altering the uptake pathway and increasing glioma localization.

  9. The effect of neurosphere culture conditions on the cellular metabolism of glioma cells.

    PubMed

    Kahlert, Ulf Dietrich; Koch, Katharina; Suwala, Abigail Kora; Hartmann, Rudolf; Cheng, Menglin; Maciaczyk, Donata; Willbold, Dieter; Eberhart, Charles G; Glunde, Kristine; Maciaczyk, Jarek

    2015-01-01

    Malignant gliomas, with an average survival time of 16-19 months after initial diagnosis, account for one of the most lethal tumours overall. Current standards in patient care provide only unsatisfying strategies in diagnostic and treatment for high-grade gliomas. Here we describe metabolic phenomena in the choline and glycine network associated with stem cell culture conditions in the classical glioma cell line U87. Using high-resolution proton magnetic resonance spectroscopy of cell culture metabolic extracts we compare the metabolic composition of U87 chronically propagated as adherent culture in medium supplemented with serum to serum-free neurosphere growth. We found that the switch to neurosphere growth, besides the increase of cells expressing the putative glioma stem cell marker CD133, modulated a number of intracellular metabolites including choline, creatine, glycine, and myo-inositol that have been previously reported as potential diagnostic markers in various tumours. These findings highlight the critical influence of culture conditions on glioma cell metabolism, and therefore particular caution should be drawn to the use of in vitro system research in order to investigate cancer metabolism.

  10. Gefitinib Radiosensitizes Stem-Like Glioma Cells: Inhibition of Epidermal Growth Factor Receptor-Akt-DNA-PK Signaling, Accompanied by Inhibition of DNA Double-Strand Break Repair

    SciTech Connect

    Kang, Khong Bee; Zhu Congju; Wong Yinling; Gao Qiuhan; Ty, Albert; Wong, Meng Cheong

    2012-05-01

    Purpose: We compared radiosensitivity of brain tumor stem cells (BTSCs) with matched nonstem glioma cells, and determined whether gefitinib enhanced BTSC radiosensitivity by inhibiting epidermal growth factor receptor (EGFR)-Akt-DNA-dependent protein kinase (DNA-PK) signaling, followed by enhanced DNA double-stand breaks (DSBs) and inhibition of DSB repair. Methods and Materials: Radiosensitivity of stem-like gliomaspheres and nonstem glioma cells (obtained at patient neurosurgical resection) were evaluated by clonogenic assays, {gamma}-H{sub 2}AX immunostaining and cell cycle distribution. Survival of irradiated and nonirradiated NOD-SCID mice intracranially implanted with stem-like gliomaspheres were monitored. Glioma cells treated with gefitinib, irradiation, or both were assayed for clonogenic survival, {gamma}-H{sub 2}AX immunostaining, DNA-PKcs expression, and phosphorylation of EGFR and Akt. Results: Stem-like gliomaspheres displayed BTSC characteristics of self-renewal; differentiation into lineages of neurons, oligodendrocytes, and astrocytes; and initiation of glioma growth in NOD-SCID mice. Irradiation dose-dependently reduced clonogenic survival, induced G{sub 2}/M arrest and increased {gamma}-H{sub 2}AX immunostaining of nonstem glioma cells, but not stem-like gliomaspheres. There was no difference in survival of irradiated and nonirradiated mice implanted with stem-like gliomaspheres. The addition of gefitinib significantly inhibited clonogenic survival, increased {gamma}-H{sub 2}AX immunostaining, and reduced DNA-PKcs expression of irradiated stem-like gliomaspheres, without affecting irradiated-nonstem glioma cells. Gefitinib alone, and when combined with irradiation, inhibited phosphorylation of EGFR (Y1068 and Y1045) and Akt (S473) in stem-like gliomaspheres. In nonstem glioma cells, gefitinib alone inhibited EGFR Y1068 phosphorylation, with further inhibition by combined gefitinib and irradiation. Conclusions: Stem-like gliomaspheres are

  11. The tropism of neurally differentiated bone marrow stromal cells towards C6 glioma.

    PubMed

    Long, Qianfa; Liu, Weiping; Zhong, Jun; Yi, Xicai; Liu, Yang; Liu, Yuanyang; Yang, Yang; Han, Rui; Fei, Zhou

    2011-10-24

    Recent studies have indicated that bone marrow stromal cells (BMSCs) have significant tropism towards glioma which makes them play an important role in carrying genes/drugs to inhibit the growth of glioma as cell vehicles. But BMSCs may differentiate into neural cells under entocranial environment and few researches support the idea that neurally differentiated bone marrow stromal cells (N-D-BMSCs) still hold the capacity of migrating to the tumor sites. The aim of our study was to investigate the tropism of N-D-BMSCs towards C6 glioma. In vitro migration assay was employed by transwell co-culture system and Student's t-test analysis indicated that N-D-BMSCs had the significant tropism towards C6 glioma-conditioned medium (GCM) (P<0.01). Furthermore, the vascular endothelial growth factor (VEGF) bioactivity of the C6 GCM was neutralized by the anti-rat VEGF antibody and our data suggested that the VEGF from C6 GCM hold chemoattraction for N-D-BMSCs and some other cytokines from the C6 GCM may be responsible for the chemoattraction for N-D-BMSCs. In vivo migration assay was carried out with cells transplantation and one way ANOVA analysis indicated that the tropism of N-D-BMSCs towards C6 glioma sites presented time variation (P-value=2.9E-20). Moreover, multiple comparisons for the time variables with the Student's t-test and the results suggested that the migration capacity of N-D-BMSCs towards C6 glioma sites reach the peak on the 7th day after transplantation. These results demonstrate that N-D-BMSCs as well as BMSCs have significant tropism towards C6 glioma.

  12. MiR-16 modulate temozolomide resistance by regulating BCL-2 in human glioma cells.

    PubMed

    Han, Jing; Chen, Qianxue

    2015-01-01

    Temozolomide (TMZ) with radiotherapy is the current standard of care for newly diagnosed glioma. However, glioma patients who are treated with the drug often develop resistance to it and some other drugs. Recently studies have shown that microRNAs (miRNAs) play an important role in drug resistance. In present study, we first examined the sensitivity to temozolomide in six glioma cell lines, and established a resistant variant, U251MG/TR cells from TMZ-sensitive glioma cell line, U251MG. We then performed a comprehensive analysis of miRNA expressions in U251MG/TR and parental cells using cancer microRNA PCR Array. Among the downregulated microRNAs was miR-16, members of miR-15/16 family, whose expression was further validated by qRT-PCR in U251MG/TR and U251MG cells. The selective microRNA, miR-16 mimics or inhibitor was respectively transfected into U251MG/TR cells and AM38 cell. We found that treatment with the mimics of miR-16 greatly decreased the sensitivity of U251MG/TR cells to temozolomide, while sensitivity to these drugs was increased by treatment with the miR-16 inhibitor. In addition, the downregulation of miR-16 in temozolomide-sensitive AM38 cells was concurrent with the upregulation of Bcl-2 protein. Conversely, overexpression of miR-16 in temozolomide-resistant cells inhibited Bcl-2 expression and decreased temozolomide resistance. In conclusion, MiR-16 mediated temozolomide-resistance in glioma cells by modulation of apoptosis via targeting Bcl-2, which suggesting that miR-16 and Bcl-2 would be potential therapeutic targets for glioma therapy.

  13. Sevoflurane inhibits the migration and invasion of glioma cells by upregulating microRNA-637.

    PubMed

    Yi, Wenbo; Li, Dongliang; Guo, Yongmin; Zhang, Yan; Huang, Bin; Li, Xingang

    2016-12-01

    Cancer cell migration and invasion are essential features of the metastatic process. Volatile anesthetic sevoflurane inhibits the migration and invasion of multiple cancer cell lines; however, its effects on glioma cells are unclear. Emerging evidence suggests that microRNA (miRNA)-637 regulates glioma cell migration and invasion through the Akt1 pathway. Sevoflurane has been shown to modulate a number of miRNAs. In the present study, we examined whether sevoflurane inhibits glioma cell migration and invasion and, if so, whether these beneficial effects are mediated by miRNA-637. U251 glioma cells were treated without (control) or with sevoflurane at low, moderate or high concentrations for 6 h. To explore the molecular mechanisms, an additional group of U251 cells was treated with a miRNA‑637 inhibitor prior to treatment with a high concentration of sevoflurane. Compared with the control group, sevoflurane inhibited the migration and invasion of U251 cells in a dose-dependent manner. Molecular analyses revealed that sevoflurane increased the expression of miRNA‑637 and decreased the expression of Akt1 and phosphorylated Akt1 in a dose-dependent manner. Moreover, the inhibitory effects of sevoflurane on U251 cell migration and invasion were completely abolished by pre-treatment with miRNA‑637 inhibitor, which reversed the sevoflurane-induced reduction in the expression of Akt1 and phosphorylated Akt1 in the U251 cells. These results demonstrate that sevoflurane inhibits glioma cell migration and invasion and that these beneficial effects are mediated by the upregulation of miRNA‑637, which suppresses Akt1 expression and activity. These findings may have significant clinical implications for anesthesiologists regarding the choice of volatile anesthetic agents for the surgical resection of gliomas to prevent metastases and improve patient outcomes.

  14. T Cells Enhance Stem-Like Properties and Conditional Malignancy in Gliomas

    PubMed Central

    Irvin, Dwain K.; Jouanneau, Emmanuel; Duvall, Gretchen; Zhang, Xiao-xue; Zhai, Yuying; Sarayba, Danielle; Seksenyan, Akop; Panwar, Akanksha; Black, Keith L.; Wheeler, Christopher J.

    2010-01-01

    Background Small populations of highly tumorigenic stem-like cells (cancer stem cells; CSCs) can exist within, and uniquely regenerate cancers including malignant brain tumors (gliomas). Many aspects of glioma CSCs (GSCs), however, have been characterized in non-physiological settings. Methods We found gene expression similarity superiorly defined glioma “stemness”, and revealed that GSC similarity increased with lower tumor grade. Using this method, we examined stemness in human grade IV gliomas (GBM) before and after dendritic cell (DC) vaccine therapy. This was followed by gene expression, phenotypic and functional analysis of murine GL26 tumors recovered from nude, wild-type, or DC-vaccinated host brains. Results GSC similarity was specifically increased in post-vaccine GBMs, and correlated best to vaccine-altered gene expression and endogenous anti-tumor T cell activity. GL26 analysis confirmed immune alterations, specific acquisition of stem cell markers, specifically enhanced sensitivity to anti-stem drug (cyclopamine), and enhanced tumorigenicity in wild-type hosts, in tumors in proportion to anti-tumor T cell activity. Nevertheless, vaccine-exposed GL26 cells were no more tumorigenic than parental GL26 in T cell-deficient hosts, though they otherwise appeared similar to GSCs enriched by chemotherapy. Finally, vaccine-exposed GBM and GL26 exhibited relatively homogeneous expression of genes expressed in progenitor cells and/or differentiation. Conclusions T cell activity represents an inducible physiological process capable of proportionally enriching GSCs in human and mouse gliomas. Stem-like gliomas enriched by strong T cell activity, however, may differ from other GSCs in that their stem-like properties may be disassociated from increased tumor malignancy and heterogeneity under specific host immune conditions. PMID:20539758

  15. Sox2 is translationally activated by eukaryotic initiation factor 4E in human glioma-initiating cells

    SciTech Connect

    Ge, Yuqing; Zhou, Fengbiao; Chen, Hong; Cui, Chunhong; Liu, Dan; Li, Qiuping; Yang, Zhiyuan; Wu, Guoqiang; Sun, Shuhui; Gu, Jianxin; Wei, Yuanyan; Jiang, Jianhai

    2010-07-09

    Sox2, a master transcription factor, contributes to the generation of induced pluripotent stem cells and plays significant roles in sustaining the self-renewal of neural stem cells and glioma-initiating cells. Understanding the functional differences of Sox2 between glioma-initiating cells and normal neural stem cells would contribute to therapeutic approach for treatment of brain tumors. Here, we first demonstrated that Sox2 could contribute to the self-renewal and proliferation of glioma-initiating cells. The following experiments showed that Sox2 was activated at translational level in a subset of human glioma-initiating cells compared with the normal neural stem cells. Further investigation revealed there was a positive correlation between Sox2 and eukaryotic initiation factor 4E (eIF4E) in glioma tissues. Down-regulation of eIF4E decreased Sox2 protein level without altering its mRNA level in glioma-initiating cells, indicating that Sox2 was activated by eIF4E at translational level. Furthermore, eIF4E was presumed to regulate the expression of Sox2 by its 5' untranslated region (5' UTR) sequence. Our results suggest that the eIF4E-Sox2 axis is a novel mechanism of unregulated self-renewal of glioma-initiating cells, providing a potential therapeutic target for glioma.

  16. Egr-1 and RNA POL II facilitate glioma cell GDNF transcription induced by histone hyperacetylation in promoter II.

    PubMed

    Zhang, Bao-Le; Guo, Ting-Wen; Gao, Le-Le; Ji, Guang-Quan; Gu, Xiao-He; Shao, Yu-Qi; Yao, Rui-Qin; Gao, Dian-Shuai

    2017-02-06

    The specific mechanisms for epigenetic regulation of gene transcription remain to be elucidated. We previously demonstrated that hyperacetylation of histone H3K9 in promoter II of glioma cells promotes high transcription of the glial cell line-derived neurotrophic factor (GDNF) gene. This hyperacetylation significantly enhanced Egr-1 binding and increased the recruitment of RNA polymerase II (RNA POL II) to that region (P < 0.05). Egr-1 expression was abnormally increased in C6 glioma cells. Further overexpression of Egr-1 significantly increased Egr-1 binding to GDNF promoter II, while increasing RNA POL II recruitment, thus increasing GDNF transcription (P < 0.01). When the acetylation of H3K9 in the Egr-1 binding site was significantly reduced by the histone acetyltransferase (HAT) inhibitor curcumin, binding of Egr-1 to GDNF promoter II, RNA POL II recruitment, and GDNF mRNA expression were significantly downregulated (P < 0.01). Moreover, curcumin attenuated the effects of Egr-1 overexpression on Egr-1 binding, RNA POL II recruitment, and GDNF transcription (P < 0.01). Egr-1 and RNA POL II co-existed in the nucleus of C6 glioma cells, with overlapping regions, but they were not bound to each other. In conclusion, highly expressed Egr-1 may be involved in the recruitment of RNA POL II in GDNF promoter II in a non-binding manner, and thereby involved in regulating GDNF transcription in high-grade glioma cells. This regulation is dependent on histone hyperacetylation in GDNF promoter II.

  17. Systemic T Cells Immunosuppression of Glioma Stem Cell-Derived Exosomes Is Mediated by Monocytic Myeloid-Derived Suppressor Cells

    PubMed Central

    Domenis, Rossana; Cesselli, Daniela; Toffoletto, Barbara; Bourkoula, Evgenia; Caponnetto, Federica; Manini, Ivana; Beltrami, Antonio Paolo; Ius, Tamara; Skrap, Miran; Di Loreto, Carla

    2017-01-01

    A major contributing factor to glioma development and progression is its ability to evade the immune system. Nano-meter sized vesicles, exosomes, secreted by glioma-stem cells (GSC) can act as mediators of intercellular communication to promote tumor immune escape. Here, we investigated the immunomodulatory properties of GCS-derived exosomes on different peripheral immune cell populations. Healthy donor peripheral blood mononuclear cells (PBMCs) stimulated with anti-CD3, anti-CD28 and IL-2, were treated with GSC-derived exosomes. Phenotypic characterization, cell proliferation, Th1/Th2 cytokine secretion and intracellular cytokine production were analysed by distinguishing among effector T cells, regulatory T cells and monocytes. In unfractionated PBMCs, GSC-derived exosomes inhibited T cell activation (CD25 and CD69 expression), proliferation and Th1 cytokine production, and did not affect cell viability or regulatory T-cell suppression ability. Furthermore, exosomes were able to enhance proliferation of purified CD4+ T cells. In PBMCs culture, glioma-derived exosomes directly promoted IL-10 and arginase-1 production and downregulation of HLA-DR by unstimulated CD14+ monocytic cells, that displayed an immunophenotype resembling that of monocytic myeloid-derived suppressor cells (Mo-MDSCs). Importantly, the removal of CD14+ monocytic cell fraction from PBMCs restored T-cell proliferation. The same results were observed with exosomes purified from plasma of glioblastoma patients. Our results indicate that glioma-derived exosomes suppress T-cell immune response by acting on monocyte maturation rather than on direct interaction with T cells. Selective targeting of Mo-MDSC to treat glioma should be considered with regard to how immune cells allow the acquirement of effector functions and therefore counteracting tumor progression. PMID:28107450

  18. Bystander effect in glioma suicide gene therapy using bone marrow stromal cells.

    PubMed

    Li, Shaoyi; Gu, Chunyu; Gao, Yun; Amano, Shinji; Koizumi, Shinichiro; Tokuyama, Tsutomu; Namba, Hiroki

    2012-11-01

    An established rat intracranial glioma was successfully treated through the tumoricidal bystander effect generated by intratumoral injection of rat bone marrow stromal cells (BMSCs) transduced with the herpes simplex virus-thymidine kinase gene (BMSCtk cells) followed by systemic ganciclovir administration. In the present study, we tested the bystander effect of this treatment strategy when using human BMSCs as the vector cells. Human BMSCtk cells were mixed with various kinds of brain tumor cell lines (human and rat glioma cells) and examined in vitro and in vivo tumoricidal bystander effects, by co-culture study and co-implantation study in the nude mouse, respectively. A significant in vitro bystander effect was observed between human BMSCtk cells and any of the tumor cells examined in the ganciclovir-containing medium. A potent in vivo bystander effect against human and rat glioma cells was also demonstrated when ganciclovir was administered. Migratory activity of the human BMSCs toward the tumor cells was enhanced by the conditioned media obtained from both human and rat glioma cells compared to the fresh media. The results of this study have demonstrated that the bystander effect generated by BMSCtk cells and ganciclovir is not cell type-specific, suggesting that the strategy would be quite feasible for clinical use.

  19. Effective transvascular delivery of nanoparticles across the blood-brain tumor barrier into malignant glioma cells

    PubMed Central

    Sarin, Hemant; Kanevsky, Ariel S; Wu, Haitao; Brimacombe, Kyle R; Fung, Steve H; Sousa, Alioscka A; Auh, Sungyoung; Wilson, Colin M; Sharma, Kamal; Aronova, Maria A; Leapman, Richard D; Griffiths, Gary L; Hall, Matthew D

    2008-01-01

    Background Effective transvascular delivery of nanoparticle-based chemotherapeutics across the blood-brain tumor barrier of malignant gliomas remains a challenge. This is due to our limited understanding of nanoparticle properties in relation to the physiologic size of pores within the blood-brain tumor barrier. Polyamidoamine dendrimers are particularly small multigenerational nanoparticles with uniform sizes within each generation. Dendrimer sizes increase by only 1 to 2 nm with each successive generation. Using functionalized polyamidoamine dendrimer generations 1 through 8, we investigated how nanoparticle size influences particle accumulation within malignant glioma cells. Methods Magnetic resonance and fluorescence imaging probes were conjugated to the dendrimer terminal amines. Functionalized dendrimers were administered intravenously to rodents with orthotopically grown malignant gliomas. Transvascular transport and accumulation of the nanoparticles in brain tumor tissue was measured in vivo with dynamic contrast-enhanced magnetic resonance imaging. Localization of the nanoparticles within glioma cells was confirmed ex vivo with fluorescence imaging. Results We found that the intravenously administered functionalized dendrimers less than approximately 11.7 to 11.9 nm in diameter were able to traverse pores of the blood-brain tumor barrier of RG-2 malignant gliomas, while larger ones could not. Of the permeable functionalized dendrimer generations, those that possessed long blood half-lives could accumulate within glioma cells. Conclusion The therapeutically relevant upper limit of blood-brain tumor barrier pore size is approximately 11.7 to 11.9 nm. Therefore, effective transvascular drug delivery into malignant glioma cells can be accomplished by using nanoparticles that are smaller than 11.7 to 11.9 nm in diameter and possess long blood half-lives. PMID:19094226

  20. RhoGDIα suppresses self-renewal and tumorigenesis of glioma stem cells

    PubMed Central

    Wu, Fan; Hu, Peishan; Li, Dengke; Hu, Yan; Qi, Yingjiao; Yin, Bin; Jiang, Tao; Yuan, Jiangang; Han, Wei; Peng, Xiaozhong

    2016-01-01

    Glioma stem cells (GSCs) are a subset of tumor cells that drive glioma initiation and progression. The molecular mechanisms underlying the maintenance of GSCs are still poorly understood. Here we investigated the role of Rho GDP dissociation inhibitor α (RhoGDIα) in GSCs. RhoGDIα was down-regulated in glioma stem cells. Over-expression of RhoGDIα suppressed the self-renewal and tumorigenesis of GSCs. Further data showed that RhoGDIα inhibited the transcription activity of stem cell marker Oct4. Moreover, inactivation of ROCK1, a downstream effector of RhoGDIα, also decreased the self-renewal and Oct4 transcription activity, and rescued the effects caused by RhoGDIα knockdown. Our results indicate that RhoGDIα is involved in the maintenance of GSCs. PMID:27557508

  1. RB mutation and RAS overexpression induce resistance to NK cell-mediated cytotoxicity in glioma cells.

    PubMed

    Orozco-Morales, Mario; Sánchez-García, Francisco Javier; Golán-Cancela, Irene; Hernández-Pedro, Norma; Costoya, Jose A; de la Cruz, Verónica Pérez; Moreno-Jiménez, Sergio; Sotelo, Julio; Pineda, Benjamín

    2015-01-01

    Several theories aim to explain the malignant transformation of cells, including the mutation of tumor suppressors and proto-oncogenes. Deletion of Rb (a tumor suppressor), overexpression of mutated Ras (a proto-oncogene), or both, are sufficient for in vitro gliomagenesis, and these genetic traits are associated with their proliferative capacity. An emerging hallmark of cancer is the ability of tumor cells to evade the immune system. Whether specific mutations are related with this, remains to be analyzed. To address this issue, three transformed glioma cell lines were obtained (Rb(-/-), Ras(V12), and Rb(-/-)/Ras(V12)) by in vitro retroviral transformation of astrocytes, as previously reported. In addition, Ras(V12) and Rb(-/-)/Ras(V12) transformed cells were injected into SCID mice and after tumor growth two stable glioma cell lines were derived. All these cells were characterized in terms of Rb and Ras gene expression, morphology, proliferative capacity, expression of MHC I, Rae1δ, and Rae1αβγδε, mult1, H60a, H60b, H60c, as ligands for NK cell receptors, and their susceptibility to NK cell-mediated cytotoxicity. Our results show that transformation of astrocytes (Rb loss, Ras overexpression, or both) induced phenotypical and functional changes associated with resistance to NK cell-mediated cytotoxicity. Moreover, the transfer of cell lines of transformed astrocytes into SCID mice increased resistance to NK cell-mediated cytotoxicity, thus suggesting that specific changes in a tumor suppressor (Rb) and a proto-oncogene (Ras) are enough to confer resistance to NK cell-mediated cytotoxicity in glioma cells and therefore provide some insight into the ability of tumor cells to evade immune responses.

  2. Synapse formation between clonal neuroblastoma X glioma hybrid cells and striated muscle cells.

    PubMed Central

    Nelson, P; Christian, C; Nirenberg, M

    1976-01-01

    Clonal neuroblastoma X glioma hybrid cells were shown to form synapses with cultured, striated muscle cells. The properties of the synapses between hybrid and muscle cells were similar to those of the normal, neuromuscular synapse at an early stage of development. The number of synapses formed and the efficiency of transmission across synapses were found to be regulated, apparently independently, by components in the culture medium. Under appropriate conditions synapses were found with 20% of the hybrid-muscle cell pairs examined; thus, the hybrid cells form synapses with relatively high frequency. Images PMID:1061105

  3. Dynamics of circulating gamma delta T cell activity in an immunocompetent mouse model of high-grade glioma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Human gamma delta 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 m...

  4. Nestin+cells forming spheroids aggregates resembling tumorspheres in experimental ENU-induced gliomas.

    PubMed

    García-Blanco, Alvaro; Bulnes, Susana; Pomposo, Iñigo; Carrasco, Alex; Lafuente, José Vicente

    2016-12-01

    Nestin+cells from spheroid aggregates display typical histopathological features compatible with cell stemness. Nestin and CD133+cells found in glioblastomas, distributed frequently around aberrant vessels, are considered as potential cancer stem cells. They are possible targets for antitumoral therapy because they lead the tumorigenesis, invasiveness and angiogenesis. However, little is known about their role and presence in low-grade gliomas. The aim of this work is to localize and characterize the distribution of these cells inside tumors during the development of experimental endogenous glioma. For this study, a single dose of Ethyl-nitrosourea was injected into pregnant rats. Double immunofluorescences were performed in order to identify stem-like and differentiated cells. Low-grade gliomas display Nestin+cells distributed throughout the tumor. More malignant gliomas show, in addition to that, a perivascular location with some Nestin+cells co-expressing CD133 or VEGF, and the intratumoral spheroid aggregates of Nestin/CD133+cells. These structures are encapsulated by well-differentiated VEGF/GFAP+cells. Spheroid aggregates increase in size in the most malignant stages. Spheroid aggregates have morphological and phenotypic similarities to in vitro neurospheres and could be an in vivo analogue of them. These arrangements could be a reservoir of undifferentiated cells formed to escape adverse microenvironments.

  5. RAD18 mediates resistance to ionizing radiation in human glioma cells

    SciTech Connect

    Xie, Chen; Wang, Hongwei; Cheng, Hongbin; Li, Jianhua; Wang, Zhi Yue, Wu

    2014-02-28

    Highlights: • RAD18 is an important mediator of the IR-induced resistance in glioma cell lines. • RAD18 overexpression confers resistance to IR-mediated apoptosis. • The elevated expression of RAD18 is associated with recurrent GBM who underwent IR therapy. - Abstract: Radioresistance remains a major challenge in the treatment of glioblastoma multiforme (GBM). RAD18 a central regulator of translesion DNA synthesis (TLS), has been shown to play an important role in regulating genomic stability and DNA damage response. In the present study, we investigate the relationship between RAD18 and resistance to ionizing radiation (IR) and examined the expression levels of RAD18 in primary and recurrent GBM specimens. Our results showed that RAD18 is an important mediator of the IR-induced resistance in GBM. The expression level of RAD18 in glioma cells correlates with their resistance to IR. Ectopic expression of RAD18 in RAD18-low A172 glioma cells confers significant resistance to IR treatment. Conversely, depletion of endogenous RAD18 in RAD18-high glioma cells sensitized these cells to IR treatment. Moreover, RAD18 overexpression confers resistance to IR-mediated apoptosis in RAD18-low A172 glioma cells, whereas cells deficient in RAD18 exhibit increased apoptosis induced by IR. Furthermore, knockdown of RAD18 in RAD18-high glioma cells disrupts HR-mediated repair, resulting in increased accumulation of DSB. In addition, clinical data indicated that RAD18 was significantly higher in recurrent GBM samples that were exposed to IR compared with the corresponding primary GBM samples. Collectively, our findings reveal that RAD18 may serve as a key mediator of the IR response and may function as a potential target for circumventing IR resistance in human GBM.

  6. Punicalagin induces apoptotic and autophagic cell death in human U87MG glioma cells

    PubMed Central

    Wang, Shyang-guang; Huang, Ming-hung; Li, Jui-hsiang; Lai, Fu-i; Lee, Horng-mo; Hsu, Yuan-nian

    2013-01-01

    Aim: To investigate the effects of punicalagin, a polyphenol isolated from Punica granatum, on human U87MG glioma cells in vitro. Methods: The viability of human U87MG glioma cells was evaluated using MTT assay. Cell cycle was detected with flow cytometry analysis. The levels of Bcl-2, cleaved caspase-9, cleaved poly(ADP-ribose) polymerase (PARP), phosphor-AMPK and phosphor-p27 at Thr198 were measured using immunoblot analyses. Caspase-3 activity was determined with spectrophotometer. To determine autophagy, LC3 cleavage and punctate patterns were examined. Results: Punicalagin (1-30 μg/mL) dose-dependently inhibited the cell viability in association with increased cyclin E level and decreased cyclin B and cyclin A levels. The treatment also induced apoptosis as shown by the cleavage of PARP, activation of caspase-9, and increase of caspase-3 activity in the cells. However, pretreatment of the cells with the pan-caspase inhibitor z-DEVD-fmk (50 μmol/L) did not completely prevent the cell death. On the other hand, punicalagin treatment increased LC3-II cleavage and caused GFP-LC3-II-stained punctate pattern in the cells. Suppressing autophagy of cells with chloroquine (1-10 μmol/L) dose-dependently alleviated the cell death caused by punicalagin. Punicalagin (1-30 μg/mL) also increased the levels phosphor-AMPK and phosphor-p27 at Thr198 in the cells, which were correlated with the induction of autophagic cell death. Conclusion: Punicalagin induces human U87MG glioma cell death through both apoptotic and autophagic pathways. PMID:24077634

  7. SHMT2 drives glioma cell survival in ischaemia but imposes a dependence on glycine clearance.

    PubMed

    Kim, Dohoon; Fiske, Brian P; Birsoy, Kivanc; Freinkman, Elizaveta; Kami, Kenjiro; Possemato, Richard L; Chudnovsky, Yakov; Pacold, Michael E; Chen, Walter W; Cantor, Jason R; Shelton, Laura M; Gui, Dan Y; Kwon, Manjae; Ramkissoon, Shakti H; Ligon, Keith L; Kang, Seong Woo; Snuderl, Matija; Vander Heiden, Matthew G; Sabatini, David M

    2015-04-16

    Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumour microenvironment. Here we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischaemic zones of gliomas. In human glioblastoma multiforme, mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumour regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumour environment, but also renders these cells sensitive to glycine cleavage system inhibition.

  8. Alpha-aminoisobutyric acid transport into human glia and glioma cells in culture.

    PubMed

    Ronquist, G; Agren, G; Ponten, J; Westermark, B

    1976-11-01

    The AIB transport into human glia and glioma cells in culture has been studied. Because of the high affinity of AIB to the plastic culture dishes, a special washing technique had to be developed. With this technique, it was possible to perform transport experiments in a single plate containing about one million cells. The cells were viable, intact and adhered to the supporting medium throughout the experiment. The AIB transport into both types of cells was Na+-dependent and showed saturation kinetics when the small component of the transport due to diffusion had been subtracted. The AIB transport capacity of neoplastic glioma cells was 3.6 times higher than that of glia cells. This difference was related to the Vmax-values for the two types of cells. The apparent Km-values were the same. Inhibition experiments with other amino acids support the view that AIB is transported via System A in both glia and glioma cells. Sulfhydryl reagents (ethacrynic acid and NEM) and cytochalasin B clearly inhibited the AIB transport into glia cells whereas the effect on glioma cells was minimal.

  9. Polyoxygenated 24,28-epoxyergosterols inhibiting the proliferation of glioma cells from sea anemone Anthopleura midori.

    PubMed

    Yu, Siran; Ye, Xuewei; Chen, Lu; Lian, Xiao-Yuan; Zhang, Zhizhen

    2014-10-01

    Eleven sterols (1-11) and one carotenoid (12) were isolated and identified from sea anemone Anthopleura midori. Compounds 1-6 are rare polyoxygenated ergosterols with a 24,28-epoxy moiety. The structures of these epoxyergosterols were determined by NMR and HRESIMS analyses as well as their chemical-physical properties. Epoxyergosterols 1 and 2 were found to be new natural products and 3-6 are new compounds. Bioactive assay showed that compounds 1, 2, 3, 5, 7, 8, 11, and 12 inhibited the proliferation of rat glioma C6 and human glioma U251 cells with IC50 in a range of 2.41-80.45 μM. Further investigation suggested that 1 and 3 induced apoptosis in glioma cells and 1 blocked U251 cells at the G0/G1 phase.

  10. MicroRNAs let-7b/i suppress human glioma cell invasion and migration by targeting IKBKE directly

    SciTech Connect

    Tian, Yuan; Hao, Shaobo; Ye, Minhua; Zhang, Anling; Nan, Yang; Wang, Guangxiu; Jia, Zhifan; Yu, Kai; Guo, Lianmei; Pu, Peiyu; Huang, Qiang; Zhong, Yue

    2015-03-06

    We demonstrated that IKBKE is overexpressed in human gliomas and that the downregulation of IKBKE markedly inhibits the proliferative and invasive abilities of glioma cells, which is consistent with the results reported by several different research groups. Therefore, IKBKE represents a promising therapeutic target for the treatment of glioma. In the present study, we verified that the microRNAs let-7b and let-7i target IKBKE through luciferase assays and found that let-7b/i mimics can knock down IKBKE and upregulate E-cadherin through western blot analysis. Moreover, the expression levels of let-7b/i were significantly lower in glioma cell lines than that in normal brain tissues, as determined by quantitative real-time PCR. Furthermore, let-7b/i inhibit the invasion and migration of glioma cells, as determined through wound healing and Transwell assays. The above-mentioned data suggest that let-7b/i inhibit the invasive ability of glioma cells by directly downregulating IKBKE and indirectly upregulating E-cadherin. - Highlights: • Let-7b and let-7i are downregulated in glioma cell lines. • IKBKE is a target gene of let-7b/i. • Let-7b/i inhibit the invasion and migration of glioma cells. • Let-7b/i upregulate E-cadherin by downregulating IKBKE.

  11. TGF-β promotes glioma cell growth via activating Nodal expression through Smad and ERK1/2 pathways

    SciTech Connect

    Sun, Jing; Liu, Su-zhi; Lin, Yan; Cao, Xiao-pan; Liu, Jia-ming

    2014-01-17

    Highlights: •TGF-β promoted Nodal expression in glioma cells. •TGF-β promoted Nodal expression via activating Smad and ERK1/2 pathways. •TGF-β promotes glioma cell growth via activating Nodal expression. -- Abstract: While there were certain studies focusing on the mechanism of TGF-β promoting the growth of glioma cells, the present work revealed another novel mechanism that TGF-β may promote glioma cell growth via enhancing Nodal expression. Our results showed that Nodal expression was significantly upregulated in glioma cells when TGF-β was added, whereas the TGF-β-induced Nodal expression was evidently inhibited by transfection Smad2 or Smad3 siRNAs, and the suppression was especially significant when the Smad3 was downregulated. Another, the attenuation of TGF-β-induced Nodal expression was observed with blockade of the ERK1/2 pathway also. Further detection of the proliferation, apoptosis, and invasion of glioma cells indicated that Nodal overexpression promoted the proliferation and invasion of tumor cells and inhibited their apoptosis, resembling the effect of TGF-β addition. Downregulation of Nodal expression via transfection Nodal-specific siRNA in the presence of TGF-β weakened the promoting effect of the latter on glioma cells growth, and transfecting Nodal siRNA alone in the absence of exogenous TGF-β more profoundly inhibited the growth of glioma cells. These results demonstrated that while both TGF-β and Nodal promoted glioma cells growth, the former might exert such effect by enhancing Nodal expression, which may form a new target for glioma therapy.

  12. MicroRNA-181b inhibits cellular proliferation and invasion of glioma cells via targeting Sal-like protein 4.

    PubMed

    Zhou, Yu; Peng, Yong; Liu, Min; Jiang, Yugang

    2016-11-17

    MicroRNAs (miRs), a class of 18-25 nucleotides in length non-coding RNAs, are able to suppress gene expression by targeting complementary regions of mRNAs and inhibiting protein translation Recently, miR-181b was found to playa suppressive role in glioma, but the regulatory mechanism of miR-181b in the malignant phenotypes of glioma cells remains largely unclear. Here we found that miR-181b was significantly downregulated in glioma tissues when compared with normal brain tissues, and decreased miR-181b levels were significantly associated with high pathology grade and poor prognosis of patients with glioma. Moreover, miR-181b was also downregulated in glioma cell lines (U87, SHG44, U373, and U251) compared to normal astrocytes. Overexpression of miR-181b significantly decreased the proliferation, migration, and invasion of glioma U251 cells. Sal-like protein 4 (SALL4) was identified as a novel target gene of miR-181b in U251 cells. The expression of SALL4 was significantly upregulated in glioma tissues and cell lines, and an inverse correlation was observed between the miR-181b and SALL4 expression levels in glioma. Further investigation showed that the protein expression of SALL4 was negatively regulated by miR-181b in U251 cells. Knockdown of SALL4 significantly inhibited the proliferation, migration and invasion of U251 cells, while overexpression of SALL4 effectively reversed the suppressive effects of miR-181b on these malignant phenotypes of U251 cells. In conclusion, our study demonstrates that miR-181b has suppressive effects on the malignant phenotypes of glioma cells, partly at least, via directly targeting SALL4. Therefore, the miR-181b/SALL4 axis may become a potential therapeutic target for glioma.

  13. Dexamethasone enhances serum deprivation-induced necrotic death of rat C6 glioma cells through activation of glucocorticoid receptors.

    PubMed

    Morita, K; Ishimura, K; Tsuruo, Y; Wong, D L

    1999-01-23

    Glucocorticoids have been shown to be neurotoxic and appear to play a role in neuronal cell loss during aging and following neuropathological insults. However, very little is known about the effects of these steroid hormones on glial cells. The effect of the synthetic glucocorticoid dexamethasone (DEX) on glial cell viability was therefore examined by measuring neutral red uptake into rat C6 glioma cells. Serum deprivation markedly reduced cell viability, and this effect was significantly enhanced by DEX. Electrophoretic analysis showed that the cell damage induced by either serum deprivation alone or in combination with DEX was not accompanied by the degradation of DNA into nucleosomic fragments. Electron microscopic studies confirmed that serum deprivation and glucocorticoid treatment caused necrotic cell death. Furthermore, the effect of DEX on cell viability could be mimicked by the glucocorticoid receptor agonist RU28362, and completely prevented by the glucocorticoid receptor antagonist RU38486. These results indicate that dexamethasone can enhance the necrotic death of glioma cells induced by serum deprivation, suggesting that glucocorticoids may be involved in the chronic alteration of brain function arising from neuropathological damage to glial cells.

  14. REIC/Dkk-3 induces cell death in human malignant glioma.

    PubMed

    Mizobuchi, Yoshifumi; Matsuzaki, Kazuhito; Kuwayama, Kazuyuki; Kitazato, Keiko; Mure, Hideo; Kageji, Teruyoshi; Nagahiro, Shinji

    2008-06-01

    The progression of glioma to more malignant phenotypes results from the stepwise accumulation of genetic alterations and the consequent disruption of the apoptotic pathway and augmentation of survival signaling. REIC/Dkk-3, a member of the human Dickkopf (Dkk) family, plays a role as a suppressor of the growth of several human cancers; however, to date it has not been identified in brain tumors. We compared the gene and protein expression of REIC/Dkk-3 in human malignant glioma and normal brain tissues using quantitative real-time PCR, Western blotting, and immunohistochemistry. We also performed small interfering REIC/Dkk-3 (siREIC/Dkk-3) knockdown and REIC/Dkk-3 overexpression experiments to examine the role of REIC/Dkk-3 in human malignant glioma cells in vitro. In brain tissue from patients with malignant glioma, the gene and protein expression of REIC/Dkk-3 was lower than in normal brain tissue and was related to the malignancy grade. In the primary glioblastoma cell line, REIC/Dkk-3 transfection led to apoptosis owing to the activation of phosphorylated JUN, caspase-9, and caspase-3 and the reduction of beta-catenin; in REIC/Dkk-3 knockdown experiments, cell growth was augmented. Our results suggest that REIC/Dkk-3 regulates the growth and survival of these cells in a caspase-dependent and -independent way via modification of the Wnt signaling pathway. Our work is the first documentation that the gene and protein expression of REIC/Dkk-3 is down-regulated in human malignant glioma. Our demonstration of the mechanisms underlying REIC/Dkk-3-induced cell death indicates that REIC/Dkk-3 plays a pivotal role in the biology of human malignant glioma and suggests that REIC/Dkk-3 is a promising candidate for molecular target therapy.

  15. Overexpression of CAP1 and its significance in tumor cell proliferation, migration and invasion in glioma.

    PubMed

    Fan, Yue-Chao; Cui, Chen-Chen; Zhu, Yi-Shuo; Zhang, Lei; Shi, Meng; Yu, Jin-Song; Bai, Jin; Zheng, Jun-Nian

    2016-09-01

    Adenylate cyclase-associated protein 1 (CAP1), a protein related to the regulation of actin filaments and the Ras/cAMP pathway, is associated with tumor progression. Nevertheless, the expression level and effects of CAP1 in regards to glioma have not been reported. In the present study, we examined the expression of CAP1 in glioma and tumor adjacent normal brain tissues by tissue microarray and immunohistochemistry. Our results showed that CAP1 was overexpressed in glioma tissues in comparison with that noted in the tumor adjacent normal brain tissues and increased staining of CAP1 was found to be correlated with WHO stage. In addition, we discovered that knockdown of CAP1 by specific RNA interference markedly inhibited cell growth and caused downregulation of the proliferation markers, PCNA and cyclin A. We further demonstrated that knockdown of CAP1 inhibited cell metastatic abilities by downregulating N-cadherin and vimentin and upregulating E-cadherin. These findings revealed that CAP1 expression is markedly increased in human glioma and that downregulation of CAP1 in tumors may serve as a treatment for glioma patients.

  16. Glioma grading using cell nuclei morphologic features in digital pathology images

    NASA Astrophysics Data System (ADS)

    Reza, Syed M. S.; Iftekharuddin, Khan M.

    2016-03-01

    This work proposes a computationally efficient cell nuclei morphologic feature analysis technique to characterize the brain gliomas in tissue slide images. In this work, our contributions are two-fold: 1) obtain an optimized cell nuclei segmentation method based on the pros and cons of the existing techniques in literature, 2) extract representative features by k-mean clustering of nuclei morphologic features to include area, perimeter, eccentricity, and major axis length. This clustering based representative feature extraction avoids shortcomings of extensive tile [1] [2] and nuclear score [3] based methods for brain glioma grading in pathology images. Multilayer perceptron (MLP) is used to classify extracted features into two tumor types: glioblastoma multiforme (GBM) and low grade glioma (LGG). Quantitative scores such as precision, recall, and accuracy are obtained using 66 clinical patients' images from The Cancer Genome Atlas (TCGA) [4] dataset. On an average ~94% accuracy from 10 fold crossvalidation confirms the efficacy of the proposed method.

  17. Glioma Grading Using Cell Nuclei Morphologic Features in Digital Pathology Images

    PubMed Central

    Reza, Syed M. S.; Iftekharuddin, Khan M.

    2016-01-01

    This work proposes a computationally efficient cell nuclei morphologic feature analysis technique to characterize the brain gliomas in tissue slide images. In this work, our contributions are two-fold: 1) obtain an optimized cell nuclei segmentation method based on the pros and cons of the existing techniques in literature, 2) extract representative features by k-mean clustering of nuclei morphologic features to include area, perimeter, eccentricity, and major axis length. This clustering based representative feature extraction avoids shortcomings of extensive tile [1] [2] and nuclear score [3] based methods for brain glioma grading in pathology images. Multilayer perceptron (MLP) is used to classify extracted features into two tumor types: glioblastoma multiforme (GBM) and low grade glioma (LGG). Quantitative scores such as precision, recall, and accuracy are obtained using 66 clinical patients’ images from The Cancer Genome Atlas (TCGA) [4] dataset. On an average ~94% accuracy from 10 fold cross-validation confirms the efficacy of the proposed method. PMID:27942094

  18. Mutant tristetraprolin: a potent inhibitor of malignant glioma cell growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Malignant gliomas rely on the production of certain critical growth factors including VEGF, interleukin (IL)-6 and IL-8, to fuel rapid tumor growth, angiogenesis, and treatment resistance. Post-transcriptional regulation through adenine and uridine-rich elements of the 3' untranslated region is one ...

  19. Influences of surface coatings and components of FePt nanoparticles on the suppression of glioma cell proliferation.

    PubMed

    Sun, Haiming; Chen, Xiaohui; Chen, Dan; Dong, Mingyan; Fu, Xinning; Li, Qian; Liu, Xi; Wu, Qingzhi; Qiu, Tong; Wan, Tao; Li, Shipu

    2012-01-01

    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, the suppression of FePt NPs on glioma cell proliferation was dominantly determined by their surface coatings rather than their components. Therefore, these results demonstrate that, through engineering of the surface coating, FePt NPs can potentially be developed as novel therapeutic agents for malignant gliomas.

  20. Magnetofection based on superparamagnetic iron oxide nanoparticle-mediated low lncRNA HOTAIR expression decreases the proliferation and invasion of glioma stem cells

    PubMed Central

    Fang, Kan; Liu, Peifeng; Dong, Suyan; Guo, Yanjie; Cui, Xinxin; Zhu, Xiaoying; Li, Xuan; Jiang, Lianghan; Liu, Te; Wu, Yuncheng

    2016-01-01

    Glioma stem cells (GSCs) are a special subpopulation of glioma cells that are key to the sensitivity of tumors to treatments and to the possibility of tumor recurrence. Identifying new strategies that inhibit the growth of GSCs are therefore important for developing novel therapies for glioblastoma multiforme (GBM). In this study, CD133+ human glioma stem cells were isolated and cultured. Magnetic nanoparticles were used to mediate the expression of siRNAs targeting the HOTAIR (si-HOTAIR) sequence in human gliomas. Effect of downregulation of HOTAIR expression on proliferation, invasion and in vivo tumorigenicity of human GSCs and underlying molecular mechanisms were further evaluated. The results of the MTT assay and flow cytometric analysis showed that downregulation of HOTAIR expression inhibited cell proliferation and induced cell cycle arrest. Transwell assays demonstrated that downregulation of HOTAIR expression resulted in a decrease in the invasive capability of GSCs. Moreover, magnetic nanoparticle-mediated low expression of HOTAIR effectively reduced the tumorigenic capacity of glioma stem cells in vivo. In addition, the results of qRT-PCR and western blot analysis demonstrated that downregulation of HOTAIR expression significantly increased the expression of PDCD4 in GSCs, in addition to reducing the expression of CCND1 and CDK4. An in-depth mechanistic analysis showed that downregulation of HOTAIR expression reduced the recruitment of downstream molecules, EZH2 and LSD1, thereby activating the expression of PDCD4 at the transcriptional level. In conclusion, downregulation of HOTAIR expression effectively promoted the expression of PDCD4, thereby inhibiting the proliferation, invasion and in vivo tumorigenicity of human GSCs. PMID:27277755

  1. Glucocorticoids and the cell surface of human glioma cells: relationship to cytostasis.

    PubMed

    Mackie, A E; Freshney, R I; Akturk, F; Hunt, G

    1988-12-01

    The glucocorticoid hormones methyl prednisolone and dexamethasone were shown to be cytostatic, but not cytotoxic, at high cell densities for early passage and continuous cell lines from human glioma at 0.25 microM and above, in the presence or absence of serum. In the absence of serum both steroids at 2.5 nM increased the saturation density close to the level reached in serum. Examination of the iodinated glycoproteins of the cell surface by gel electrophoresis did not reveal any consistent change. However, gel exclusion chromatography of protease digests of the cell surface and of material released into the medium showed an increase in incorporation of 3H-glucosamine in pronase digests after treatment with methyl prednisolone. Ion exchange chromatography showed that sulphated glycosaminoglycans, particularly heparan sulphate, increased and hyaluronic acid decreased in response to steroids, and there was increased retention of GAGs on the cell surface relative to the released fraction. It was concluded that glucocorticoid hormones modify the cell surface of human glioma cells and that this may contribute to enhanced cell intraction and lead to increased density limitation of cell proliferation.

  2. Glucocorticoids and the cell surface of human glioma cells: relationship to cytostasis.

    PubMed Central

    Mackie, A. E.; Freshney, R. I.; Akturk, F.; Hunt, G.

    1988-01-01

    The glucocorticoid hormones methyl prednisolone and dexamethasone were shown to be cytostatic, but not cytotoxic, at high cell densities for early passage and continuous cell lines from human glioma at 0.25 microM and above, in the presence or absence of serum. In the absence of serum both steroids at 2.5 nM increased the saturation density close to the level reached in serum. Examination of the iodinated glycoproteins of the cell surface by gel electrophoresis did not reveal any consistent change. However, gel exclusion chromatography of protease digests of the cell surface and of material released into the medium showed an increase in incorporation of 3H-glucosamine in pronase digests after treatment with methyl prednisolone. Ion exchange chromatography showed that sulphated glycosaminoglycans, particularly heparan sulphate, increased and hyaluronic acid decreased in response to steroids, and there was increased retention of GAGs on the cell surface relative to the released fraction. It was concluded that glucocorticoid hormones modify the cell surface of human glioma cells and that this may contribute to enhanced cell intraction and lead to increased density limitation of cell proliferation. PMID:3254724

  3. The miR-204-3p-targeted IGFBP2 pathway is involved in xanthohumol-induced glioma cell apoptotic death.

    PubMed

    Chen, Peng-Hsu; Chang, Cheng-Kuei; Shih, Chwen-Ming; Cheng, Chia-Hsiung; Lin, Cheng-Wei; Lee, Chin-Cheng; Liu, Ann-Jeng; Ho, Kuo-Hao; Chen, Ku-Chung

    2016-11-01

    Xanthohumol (XN), a prenylated chalcone extracted from hop plant Humulus lupulus L. (Cannabaceae), has potential for cancer therapy, including gliomas. Micro (mi)RNAs are small noncoding RNAs that control gene expression. Several miRNAs have been identified to participate in regulating glioma development. However, no studies have demonstrated whether miRNA is involved in XN cytotoxicity resulting in glioma cell death. This study investigated the effects of XN-mediated miRNA expression in activating apoptotic pathways in glioblastoma U87 MG cells. First, we found that XN significantly reduced cell viability and induced apoptosis via pro-caspase-3/8 cleavage and poly(ADP ribose) polymerase (PARP) degradation. We also identified that pro-caspase-9 cleavage, Bcl2 family expression changes, mitochondrial dysfunction, and intracellular ROS generation also participated in XN-induced glioma cell death. With a microarray analysis, miR-204-3p was identified as the most upregulated miRNA induced by XN cytotoxicity. The extracellular signal-regulated kinase (ERK)/c-Fos pathway was validated to participate in XN-upregulated miR-204-3p expression. With a promoter assay and ChIP analysis, we found that c-Fos dose-dependently bound to the miR-204-3p gene promoter region. Furthermore, miR-204-3p levels decreased in several glioma cell lines compared to astrocytes. Overexpression of miR-204-3p enhanced glioma cell apoptosis. IGFBP2, an upregulated regulator of glioma proliferation, was validated by a TCGA analysis as a direct target gene of miR-204-3p. XN's inhibition of the IGFBP2/AKT/Bcl2 pathway via miR-204-3p targeting played a critical role in mediating glioma cell death. These results emphasized that the XN-mediated miR-204-3p network may provide novel therapeutic strategies for future glioblastoma therapy and drug development.

  4. ALA-PDT of glioma cell micro-clusters in BD-IX rat brain

    NASA Astrophysics Data System (ADS)

    Madsen, Steen J.; Angell-Petersen, Even; Spetalen, Signe; Carper, Stephen W.; Ziegler, Sarah A.; Hirschberg, Henry

    2006-02-01

    A significant contributory factor to the poor prognosis of patients with glioblastoma multiforme is the inability of conventional treatments to eradicate infiltrating glioma cells. A syngeneic rat brain tumor model is used to investigate the effects of aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) on small clusters of tumor cells sequestered in normal brain. The intrinsic sensitivity of rat glioma cells to PDT was investigated by exposing ALA-incubated cells to a range of radiant exposures and irradiances using 635 nm light. Biodistribution studies were undertaken on tumor-bearing animals in order to determine the tumor selectivity of the photosensitizer following systemic administration (i.p.) of ALA. Effects of ALA-PDT on normal brain and gross tumor were evaluated using histopathology. Effects of PDT on isolated glioma cells in normal brain were investigated by treating animals 48 h after tumor cell implantation: a time when the micro-clusters of cells are protected by an intact blood-brain-barrier (BBB). Rat glioma cells in monolayer are susceptible to ALA-PDT - lower irradiances are more effective than higher ones. Fluorescence microscopy of frozen tissue sections showed that photosensitizer is produced with better than 200:1 tumor-to-normal tissue selectivity following i.p. ALA administration. ALA-PDT resulted in significant damage to both gross tumor and normal brain, however, the treatment failed to prolong survival of animals with newly implanted glioma cells compared to non-treated controls if the drug was delivered either i.p. or directly into the brain. In contrast, animals inoculated with tumor cells pre-incubated in vitro with ALA showed a significant survival advantage in response to PDT.

  5. Immature mesenchymal stem cell-like pericytes as mediators of immunosuppression in human malignant glioma.

    PubMed

    Ochs, Katharina; Sahm, Felix; Opitz, Christiane A; Lanz, Tobias V; Oezen, Iris; Couraud, Pierre-Olivier; von Deimling, Andreas; Wick, Wolfgang; Platten, Michael

    2013-12-15

    Malignant gliomas are primary brain tumors characterized by profound local immunosuppression. While the remarkable plasticity of perivascular cells - resembling mesenchymal stem cells (MSC) - in malignant gliomas and their contribution to angiogenesis is increasingly recognized, their role as potential mediators of immunosuppression is unknown. Here we demonstrate that FACS-sorted malignant glioma-derived pericytes (HMGP) were characterized by the expression of CD90, CD248, and platelet-derived growth factor receptor-β (PDGFR-β). HMGP shared this expression profile with human brain vascular pericytes (HBVP) and human MSC (HMSC) but not human cerebral microvascular endothelial cells (HCMEC). CD90+PDGFR-β+perivascular cells distinct from CD31+ endothelial cells accumulated in human gliomas with increasing degree of malignancy and negatively correlated with the presence of blood vessel-associated leukocytes and CD8+ T cells. Cultured CD90+PDGFR-β+HBVP were equally capable of suppressing allogeneic or mitogen-activated T cell responses as human MSC. HMGP, HBVP and HMSC expressed prostaglandin E synthase (PGES), inducible nitric oxide synthase (iNOS), human leukocyte antigen-G (HLA-G), hepatocyte growth factor (HGF) and transforming growth factor-β (TGF-β). These factors but not indoleamine 2,3-dioxygenase-mediated conversion of tryptophan to kynurenine functionally contributed to immunosuppression of immature pericytes. Our data provide evidence that human cerebral CD90+ perivascular cells possess T cell inhibitory capability comparable to human MSC and suggest that these cells, besides their critical role in tumor vascularization, also promote local immunosuppression in malignant gliomas and possibly other brain diseases.

  6. Glutamine synthetase gene expression and glutamate transporters in C6-glioma cells.

    PubMed

    Baber, Zafeer; Haghighat, Nasrin

    2010-12-01

    Glutamine synthetase (GS) is the major glutamate-forming enzyme of vertebrae and is accepted to be a marker of astroglial cells. Maturation of astroglial cells is characterized by an increase in GS activity, and the regulation of this enzyme is the topic of many publications. The amino acid glutamate is the major excitatory neurotransmitter in the brain and mediates normal excitatory synaptic transmission by interaction with postsynaptic receptors. Glutamate also acts as a potent neurotoxin when present at high concentration. Glutamate neurotoxicity plays an important role in the pathophysiology of many neurological disorders, such as Alzheimer's disease, Huntington's disease and amyotrophic lateral sclerosis. In the normal condition, L-glutamate is predominantly taken up, metabolized and recycled by astrocytes through the glutamate transporters (GLAST/GLT1) and glutamine synthetase (GS) catalytic activity. Because of the fundamental role of these glutamate transporters and the glutamine synthetase enzyme in controlling cerebral glutamate level, regulation of GS and studying of the glutamate transporters in glial cells is important. Astrocytes are supportive cells and act as the site of detoxification of glutamate in the brain. However, their isolation from the brain is a tedious, costly and time consuming procedure. On the other hand, the C6-glioma cells are readily available on the market. They are well characterized and have been a useful model for CNS glia in many laboratories. For this study, we used the C6-glioma cell line as a model system. We examined the presence or absence of glial specific glutamate transporters (GLTI and GLAST) in C6-glioma cells, which was done by immunocytochemistry. We also examined glutamine synthetase gene expression in these cells by treatment of the C6-glioma cells with estrogen (17ß estradiol). The findings from this study provide useful information about C6-glioma cells which makes the study of the CNS tremendously inexpensive.

  7. Mesenchymal stem cells show little tropism for the resting and differentiated cancer stem cell-like glioma cells.

    PubMed

    Liu, Zhenlin; Jiang, Zhongmin; Huang, Jianyong; Huang, Shuqiang; Li, Yanxia; Sheng, Feng; Yu, Simiao; Yu, Shizhu; Liu, Xiaozhi

    2014-04-01

    Intrinsic resistance of glioma cells to radiation and chemotherapy is currently hypothesized to be partially attributed to the existence of cancer stem cells. Emerging studies suggest that mesenchymal stem cells may serve as a potential carrier for delivery of therapeutic genes to disseminated glioma cells. However, the tropism character of mesenchymal stem cells for cancer stem cell-like glioma cells has rarely been described. In this study, we obtained homologous bone marrow-derived (BM-) and adipose tissue-derived (AT-) mesenchymal stem cells (MSCs), fibroblast, and cancer stem cell-like glioma cells (CSGCs) from tumor-bearing mice, and compared the tropism character of BM- and AT-MSCs for CSGCs with various form of existence. To characterize the cell proliferation and differentiation, the spheroids of CSGCs were cultured on the surface of the substrate with different stiffness, combined with or withdrew basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) in medium. Our results showed that the CSGCs during the process of cell proliferation, but not in resting and differentiated status, display strong tropism characteristics on both BM- and AT-MSCs, as well as the expression of their cell chemokine factors which mediate cell migration. If the conclusion is further confirmed, it may expose a fatal flaw of MSCs as tumor-targeted delivery of therapeutic agents in the treatment of the CSGCs, even other cancer stem cells, because there always exist a part of cancer stem cells that are in resting status. Overall, our findings provide novel insight into the complex issue of the MSCs as drug delivery in the treatment of brain tumors, especially in tumor stem cells.

  8. TAZ promotes temozolomide resistance by upregulating MCL-1 in human glioma cells.

    PubMed

    Tian, Tian; Li, Aimin; Lu, Hong; Luo, Ran; Zhang, Mingzhi; Li, Zhaoming

    2015-08-07

    Temozolomide is a novel cytotoxic agent currently used as first-line chemotherapy for glioblastoma multiforme (GBM). However, intrinsic or acquired chemoresistance to temozolomide remains the greatest obstacle to the successful treatment of human GBM. The principal mechanism responsible for this resistance is largely unknown. In the present study, we showed that expression of transcriptional co-activator with PDZ-binding motif (TAZ) in glioma cells correlated with temozolomide chemoresistance in human glioma cells. Overexpression of TAZ promoted temozolomide resistance in U-87MG cells, whereas knockdown of TAZ expression sensitized temozolomide-resistant U-251MG cells to temozolomide. Further, TAZ inhibits temozolomide induced apoptosis via upregulation of MCL-1 (myeloid cell leukemia 1) and high expression of TAZ predicts a poor prognosis for GBM patients. In conclusion, our results suggest that TAZ had a critical role in the resistance to temozolomide in glioma cells, and it may provide a promising target for improving the therapeutic outcome of temozolomide-resistant gliomas.

  9. Imaging Bone Morphogenetic Protein 7 Induced Cell Cycle Arrest in Experimental Gliomas12

    PubMed Central

    Klose, Anke; Waerzeggers, Yannic; Monfared, Parisa; Vukicevic, Slobodan; Kaijzel, Eric L; Winkeler, Alexandra; Wickenhauser, Claudia; Löwik, Clemens W G M; Jacobs, Andreas H

    2011-01-01

    Bone morphogenetic protein 7 (BMP-7) belongs to the superfamily of transforming growth factor β-like cytokines, which can act either as tumor suppressors or as tumor promoters depending on cell type and differentiation. Our investigations focused on analyzing the effects of BMP-7 during glioma cell proliferation in vitro and in vivo. BMP-7 treatment decreased the proliferation of Gli36ΔEGFR-LITG glioma cells up to 50%through a cell cycle arrest in the G1 phase but not by induction of apoptosis. This effect was mediated by the modulation of the expression and phosphorylation of cyclin-dependent kinase 2, cyclin-dependent kinase inhibitor p21, and downstream retinoblastoma protein. Furthermore, in vivo optical imaging of luciferase activity of Gli36ΔEGFR-LITG cells implanted intracranially into nude mice in the presence or absence of BMP-7 treatment corroborated the antiproliferative effects of this cytokine. This report clearly underlines the tumor-suppressive role of BMP-7 in glioma-derived cells. Taken together, our results indicate that manipulating the BMP/transforming growth factor β signaling cascade may serve as a new strategy for imaging-guided molecular-targeted therapy of malignant gliomas. PMID:21390190

  10. 3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

    PubMed

    Xu, Dong-Qiang; Tan, Xiao-Yu; Zhang, Bao-Wei; Wu, Tao; Liu, Ping; Sun, Shao-Jun; Cao, Yin-Guang

    2016-03-01

    The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

  11. Centrosomal Protein of 55 Regulates Glucose Metabolism, Proliferation and Apoptosis of Glioma Cells via the Akt/mTOR Signaling Pathway

    PubMed Central

    Wang, Guangzhi; Liu, Mingna; Wang, Hongjun; Yu, Shan; Jiang, Zhenfeng; Sun, Jiahang; Han, Ke; Shen, Jia; Zhu, Minwei; Lin, Zhiguo; Jiang, Chuanlu; Guo, Mian

    2016-01-01

    Introduction: Glioma is one of the most common and most aggressive brain tumors in humans. The molecular and cellular mechanisms responsible for the onset and the progression of glioma are elusive and controversial. Centrosomal protein of 55 (CEP55) was initially described as a highly coiled-coil protein that plays critical roles in cell division, but was recently identified as being overexpressed in many human cancers. The function of CEP55 has not previously been characterized in glioma. We aim to discover the effect and mechanism of CEP55 in glioma development. Method: qRT-PCR and immunohistochemistry were used to analyze CEP55 expression. Glucose uptake, western blot, MTS, CCK-8, Caspase-3 activity and TUNEL staining assays were performed to investigate the role and mechanism of CEP55 on glioma cell process. Results: We found that the levels of CEP55 expression were upregulated in glioma. In addition, CEP55 appeared to regulate glucose metabolism of glioma cells. Furthermore, knockdown of CEP55 inhibited cell proliferation and induced cell apoptosis in glioma. Finally, we provided preliminary evidence that knockdown of CEP55 inhibited glioma development via suppressing the activity of Akt/mTOR signaling. Conclusions: Our results demonstrated that CEP55 regulates glucose metabolism, proliferation and apoptosis of glioma cells via the Akt/mTOR signaling pathway, and its promotive effect on glioma tumorigenesis can be a potential target for glioma therapy in the future. PMID:27471559

  12. Impairment of stress granule assembly via inhibition of the eIF2alpha phosphorylation sensitizes glioma cells to chemotherapeutic agents.

    PubMed

    Vilas-Boas, Fabrício de Almeida Souza; da Silva, Aristóbolo Mendes; de Sousa, Lirlândia Pires; Lima, Kátia Maciel; Vago, Juliana Priscila; Bittencourt, Lucas Felipe Fernandes; Dantas, Arthur Estanislau; Gomes, Dawidson Assis; Vilela, Márcia Carvalho; Teixeira, Mauro Martins; Barcelos, Lucíola Silva

    2016-04-01

    Malignant gliomas are a lethal type of brain tumors that poorly respond to chemotherapeutic drugs. Several therapy resistance mechanisms have been characterized. However, the response to stress through mRNA translational control has not been evaluated for this type of tumor. A potential target would involve the alpha subunit of eukaryotic translation initiation factor (eIF2α) that leads to assembly of stress granules (SG) which are cytoplasmic granules mainly composed by RNA binding proteins and untranslated mRNAs. We assessed whether glioma cells are capable of assembling SG after exposure to different classes of chemotherapeutic agents through evaluation of the effects of interfering in this process by impairing the eIF2α signaling. C6 and U87MG cells were exposed to bortezomib, cisplatin, or etoposide. Forced expression of a dominant negative mutant of eIF2α (eIF2α(DN)) was employed to block this pathway. We observed that exposure to drugs stimulated SG assembly. This was reduced in eIF2α(DN)-transfected cells and this strategy enhanced chemotherapeutically-induced cell death for all drugs. Our data suggest that SG assembly occurs in glioma cells in response to chemotherapeutic drugs in an eIF2α-dependent manner and this response is relevant for drug resistance. Interfering with eIF2α signaling pathway may be a potential strategy for new co-adjuvant therapies to treat gliomas.

  13. Picosecond fluorescence lifetime imaging microscope for imaging of living glioma cells

    NASA Astrophysics Data System (ADS)

    Fang, Qiyin; Wang, Jingjing; Sun, Yinghua; Vernier, Thomas; Papaioannou, Thanassis; Jo, Javier; Thu, Mya M.; Gundersen, Martin A.; Marcu, Laura

    2005-03-01

    In this communication, we report the imaging of living glioma cells using fluorescence lifetime imaging (FLIM) technique. The growing interests in developing novel techniques for diagnosis and minimally invasive therapy of brain tumor have led to microscopic studies of subcellular structures and intracellular processes in glioma cells. Fluorescence microscopy has been used with a number of exogenous molecular probes specific for certain intracellular structures such as mitochondria, peripheral benzodiazepine receptor (PBR), and calcium concentration. When probes with overlapping emission spectra being used, separate samples are required to image each probe individually under conventional fluorescence microscopy. We have developed a wide-field FLIM microscope that uses fluorescence lifetime as an additional contrast for resolving multiple markers in the same essay. The FLIM microscope consists of a violet diode laser and a nitrogen-pumped dye laser to provide tunable sub-nanosecond excitation from UV to NIR. The detection system is based on a time-gated ICCD camera with minimum 80 ps gate width. The performance of the system was evaluated using fluorescence dyes with reported lifetime values. Living rat glioma C6 cells were stained with JC-1 and Rhodamine 123. FLIM images were acquired and their lifetimes in living cells were found in good agreements with values measured in solutions by a time-domain fluorescence spectrometer. These results indicate that imaging of glioma cells using FLIM can resolve multiple spectrally-overlapping probes and provide quantitative functional information about the intracellular environment.

  14. Caudatin Inhibits Human Glioma Cells Growth Through Triggering DNA Damage-Mediated Cell Cycle Arrest.

    PubMed

    Fu, Xiao-yan; Zhang, Shuai; Wang, Kun; Yang, Ming-feng; Fan, Cun-dong; Sun, Bao-liang

    2015-10-01

    Caudatin, one of the species of C-21 steroidal glycosides mainly isolated from the root of Cynanchum bungei Decne, exhibits potent anticancer activities. However, the mechanism remains poorly defined. In the present study, the growth inhibitory effect and mechanism of caudatin on human glioma cells were evaluated in vitro. The results revealed that caudatin time- and dose-dependently inhibited U251 and U87 cells growth. Flow cytometry analysis indicated that caudatin-induced growth inhibition against U251 and U87 cells was mainly achieved by the induction of G0/G1 and S-phase cell cycle arrest through triggering DNA damage, as convinced by the up-regulation of p53, p21, and histone phosphorylation, as well as the down-regulation of cyclin D1. Moreover, caudatin treatment also triggered the activation of ERK and inactivation of AKT pathway. LY294002 (an AKT inhibitor) addition enhanced caudation-induced AKT inhibition, indicating that caudatin inhibited U251 cells growth in an AKT-dependent manner. Taken together, these results indicate that caudatin may act as a novel cytostatic reagent against human glioma cells through the induction of DNA damage-mediated cell cycle arrest with the involvement of modulating MAPK and AKT pathways.

  15. Potassium channel blockers quinidine and caesium halt cell proliferation in C6 glioma cells via a polyamine-dependent mechanism.

    PubMed

    Weiger, T M; Colombatto, S; Kainz, V; Heidegger, W; Grillo, M A; Hermann, A

    2007-04-01

    Potassium channels are ubiquitous in cells and serve essential functions in physiology and pathophysiology. Potassium channel blockers have been shown to block tumour growth by arresting cells at the G(0)/G(1) checkpoint of the cell cycle. We investigated the effect of quinidine and caesium (Cs(+)) on cell proliferation, LDH (lactate dehydrogenase) release, free internal calcium, membrane potential, polyamine concentration, ODC (ornithine decarboxylase) activity and polyamine uptake in C6 glioma cells. The EC(50) for reducing cell proliferation was 112 microM for quinidine, whereas Cs(+) was less effective with an EC(50) of 4.75 mM. KCl or sucrose did not affect proliferation. LDH release was augmented by quinidine. Quinidine caused a transient increase in free internal calcium but decreased calcium after a 48 h incubation period. Further 300 microM quinidine depolarized the cell membrane in a similar range as did 30 mM KCl. Quinidine decreased cellular putrescine beyond detection levels while spermidine and spermine remained unaffected. ODC activity was reduced. Addition of putrescine could not override the antiproliferative effect owing to a reduced activity of the polyamine transporter. Our study indicates that the antiproliferative effect of quinidine is not due to a simple membrane depolarization but is caused by a block of ODC activity.

  16. Polyphyllin D induces apoptosis in U87 human glioma cells through the c-Jun NH2-terminal kinase pathway.

    PubMed

    Yu, Qiang; Li, Qiaoyu; Lu, Peisong; Chen, Qianxue

    2014-09-01

    Polyphyllin D (PD), an active component from a traditional medicinal herb Paris polyphylla, which has long been used for the treatment of cancer in Asian countries, has been found to hold significant antitumor activity in vivo or in vitro. However, there were few reports on the effects and underlying mechanism of PD on apoptosis in U87 human glioma cells. The present study was conducted to evaluate apoptotic induction of PD in U87 human glioma cells, and explore its underlying pathway. U87 glioma cells were cultured and treated with varied concentrations of PD (from 10(-8) to 10(-4) M). The inhibition of U87 glioma cell proliferation by PD was assessed by MTT assay. The apoptosis of U87 glioma cells was detected by flow cytometry, and western blot analysis was used to examine human B-cell leukemia/lymphoma 2 (Bcl-2), human Bcl-2 associated X protein (Bax), caspase-3, total-c-jun NH2-terminal kinase (t-JNK), and phosphorylation-JNK (p-JNK) protein expression in U87 human glioma cells. The treatment with PD for 24 h significantly inhibited the proliferation of U87 human glioma cells in a concentration-dependent manner. PD increased apoptosis and significantly upregulated the expression of Bax, caspase-3, and p-JNK associated with apoptosis, but downregulated antiapoptotic Bcl-2 expression in U87 human glioma cells. Our data provided evidences that PD induces apoptosis in U87 human glioma cells. This effect might be associated with the JNK pathway.

  17. Temozolomide reverses doxorubicin resistance by inhibiting P-glycoprotein in malignant glioma cells.

    PubMed

    Zhang, Rong; Saito, Ryuta; Shibahara, Ichiyo; Sugiyama, Shinichiro; Kanamori, Masayuki; Sonoda, Yukihiko; Tominaga, Teiji

    2016-01-01

    Temozolomide is a standard chemotherapy agent for malignant gliomas, but the efficacy is still not satisfactory. Therefore, combination chemotherapy using temozolomide with other anti-tumor compounds is now under investigation. Here we studied the mechanism of the synergistic anti-tumor effect achieved by temozolomide and doxorubicin, and elucidated the inhibitory effect of temozolomide on P-glycoprotein (P-gp). Temozolomide significantly enhanced sensitivity to P-gp substrate in glioma cells, particularly in P-gp-overexpressed cells. Synergetic effects, as determined by isobologram analysis, were observed by combining temozolomide and doxorubicin. Subsequently, flow cytometry was utilized to assess the intracellular retention of doxorubicin in cells treated with doxorubicin with or without temozolomide. Temozolomide significantly increased the accumulation of doxorubicin in these cells. The P-gp adenosine triphosphatase (ATPase) assay showed that temozolomide inhibited the ATPase activity of P-gp. In addition, temozolomide combined with doxorubicin significantly prolonged the survival of 9L intracranial allografted glioma-bearing rats compared to single agent treatment. Collectively, our findings suggest that temozolomide can reverse doxorubicin resistance by directly affecting P-gp transport activity. Combination chemotherapy using temozolomide with other agents may be effective against gliomas in clinical applications.

  18. Diversity and divergence of the glioma-infiltrating T-cell receptor repertoire

    PubMed Central

    Sims, Jennifer S.; Grinshpun, Boris; Feng, Yaping; Ung, Timothy H.; Neira, Justin A.; Samanamud, Jorge L.; Canoll, Peter; Shen, Yufeng; Sims, Peter A.; Bruce, Jeffrey N.

    2016-01-01

    Although immune signaling has emerged as a defining feature of the glioma microenvironment, how the underlying structure of the glioma-infiltrating T-cell population differs from that of the blood from which it originates has been difficult to measure directly in patients. High-throughput sequencing of T-cell receptor (TCR) repertoires (TCRseq) provides a population-wide statistical description of how T cells respond to disease. We have defined immunophenotypes of whole repertoires based on TCRseq of the α- and β-chains from glioma tissue, nonneoplastic brain tissue, and peripheral blood from patients. Using information theory, we partitioned the diversity of these TCR repertoires into that from the distribution of VJ cassette combinations and diversity due to VJ-independent factors, such as selection due to antigen binding. Tumor-infiltrating lymphocytes (TILs) possessed higher VJ-independent diversity than nonneoplastic tissue, stratifying patients according to tumor grade. We found that the VJ-independent components of tumor-associated repertoires diverge more from their corresponding peripheral repertoires than T-cell populations in nonneoplastic brain tissue, particularly for low-grade gliomas. Finally, we identified a “signature” set of TCRs whose use in peripheral blood is associated with patients exhibiting low TIL divergence and is depleted in patients with highly divergent TIL repertoires. This signature is detectable in peripheral blood, and therefore accessible noninvasively. We anticipate that these immunophenotypes will be foundational to monitoring and predicting response to antiglioma vaccines and immunotherapy. PMID:27261081

  19. Compression stiffening of brain and its effect on mechanosensing by glioma cells

    NASA Astrophysics Data System (ADS)

    Pogoda, Katarzyna; Chin, LiKang; Georges, Penelope C.; Byfield, FitzRoy J.; Bucki, Robert; Kim, Richard; Weaver, Michael; Wells, Rebecca G.; Marcinkiewicz, Cezary; Janmey, Paul A.

    2014-07-01

    Many cell types, including neurons, astrocytes and other cells of the central nervous system, respond to changes in the extracellular matrix or substrate viscoelasticity, and increased tissue stiffness is a hallmark of several disease states, including fibrosis and some types of cancers. Whether the malignant tissue in brain, an organ that lacks the protein-based filamentous extracellular matrix of other organs, exhibits the same macroscopic stiffening characteristic of breast, colon, pancreatic and other tumors is not known. In this study we show that glioma cells, like normal astrocytes, respond strongly in vitro to substrate stiffness in the range of 100 to 2000 Pa, but that macroscopic (mm to cm) tissue samples isolated from human glioma tumors have elastic moduli in the order of 200 Pa that are indistinguishable from those of normal brain. However, both normal brain and glioma tissues increase their shear elastic moduli under modest uniaxial compression, and glioma tissue stiffens more strongly under compression than normal brain. These findings suggest that local tissue stiffness has the potential to alter glial cell function, and that stiffness changes in brain tumors might arise not from increased deposition or crosslinking of the collagen-rich extracellular matrix, but from pressure gradients that form within the tumors in vivo.

  20. Phenotypic modification of human glioma and non-small cell lung carcinoma by glucocorticoids and other agents.

    PubMed

    McLean, J S; Frame, M C; Freshney, R I; Vaughan, P F; Mackie, A E; Singer, I

    1986-01-01

    Glucocorticoids are cytostatic for human glioma grown at a high cell density in cell culture. The effect is not cytotoxic, appears to involve a modification of the cell surface, and has been detected with methyl prednisolone, dexamethasone, and beta-methasone. Glucocorticoids were also found to reduce malignancy-associated properties (plasminogen activator and endothelial mitogenesis) and enhance differentiation (glutamyl synthetase activity and high affinity GABA uptake). Cytostasis was also seen at high cell densities in non-small cell lung carcinoma with a concomitant reduction in plasminogen activator activity and endothelial mitogenesis. Preliminary data on surfactant production in A549 cells suggests that the repression of malignancy-associated properties is accompanied by an increase in cell differentiation. Treatment of the WIL adenocarcinoma gown as a xenograft in nude mice caused total cessation of growth and massive central necrosis in the tumor.

  1. TGF-beta and metalloproteinases differentially suppress NKG2D ligand surface expression on malignant glioma cells.

    PubMed

    Eisele, Günter; Wischhusen, Jörg; Mittelbronn, Michel; Meyermann, Richard; Waldhauer, Inja; Steinle, Alexander; Weller, Michael; Friese, Manuel A

    2006-09-01

    NKG2D ligands (NKG2DL) are expressed by infected and transformed cells. They transmit danger signals to NKG2D-expressing immune cells, leading to lysis of NKG2DL-expressing cells. We here report that the NKG2DL MHC class I-chain-related molecules A and B (MICA/B) and UL16-binding proteins (ULBP) 1-3 are expressed in human brain tumours in vivo, while expression levels are low or undetectable in normal brain. MICA and ULBP2 expression decrease with increasing WHO grade of malignancy, while MICB and ULBP1 are expressed independently of tumour grade. We further delineate two independent mechanisms that can explain these expression patterns: (i) transforming growth factor-beta (TGF-beta) is upregulated during malignant progression and selectively downregulates MICA, ULBP2 and ULBP4 expression, while MICB, ULBP1 and ULBP3 are unaffected. (ii) Cleavage of MICA and ULBP2 is reduced by inhibition of metalloproteinases (MP), whereas no changes in the expression levels of other NKG2DL were detected. Consequently, NKG2DL-dependent NK cell-mediated lysis is enhanced by depletion of TGF-beta or inhibition of MP. Thus, escape from NKG2D-mediated immune surveillance of malignant gliomas in vivo may be promoted by the inhibition of MICA and ULBP2 expression via an autocrine TGF-beta loop and by MP-dependent shedding from the cell surface. Loss of MICA and ULBP2, in contrast to other NKG2DL, may be particularly important in glioma immune escape, and differential regulation of human NKG2DL expression is part of the immunosuppressive properties of human malignant glioma cells.

  2. Control of human glioma cell growth, migration and invasion in vitro by transforming growth factor beta 1.

    PubMed Central

    Merzak, A.; McCrea, S.; Koocheckpour, S.; Pilkington, G. J.

    1994-01-01

    Factors involved in the control of the biological properties of gliomas, the major form of brain tumour in man, are poorly documented. We investigated the role of transforming growth factor beta 1 (TGF-beta 1) in the control of proliferation of human glioma cell lines as well as normal human fetal brain cells. The data presented show that TGF-beta 1 exerts a growth-inhibitory action on both human fetal brain cells and three cell lines derived from human glioma of different grades of malignancy. In addition, this growth-inhibitory effect is dose dependent and serum independent. Since TGF-beta 1 is known to be involved in the control of cell migration during ontogenesis and oncogenesis, we investigated the role of this factor in the motile and invasive behaviour that characterises human gliomas in vivo. TGF-beta 1 was found to elicit a strong stimulation of migration and invasiveness of glioma cells in vitro. In combination with recent data showing an inverse correlation between TGF-beta 1 expression in human gliomas and survival, these findings may suggest that TGF-beta 1 plays an important role in the malignant progression of gliomas in man. A study of the molecular mechanisms involved in the antiproliferative action and the invasion-promoting action of TGF-beta 1 may help to identify new targets in therapy for brain tumours. A combined antiproliferative and anti-invasive therapy could be envisaged. Images Figure 3 PMID:8054266

  3. The Effects of Thermal Preconditioning on Oncogenic and Intraspinal Cord Growth Features of Human Glioma Cells.

    PubMed

    Zeng, Xiang; Han, Inbo; Abd-El-Barr, Muhammad; Aljuboori, Zaid; Anderson, Jamie E; Chi, John H; Zafonte, Ross D; Teng, Yang D

    2016-12-13

    The adult rodent spinal cord presents an inhibitory environment for donor cell survival, impeding efficiency for xenograft-based modeling of gliomas. We postulated that mild thermal preconditioning may influence the fate of the implanted tumor cells. To test this hypothesis, high-grade human astrocytoma G55 and U87 cells were cultured under 37C and 38.5C to mimic regular experimental or core body temperatures of rodents, respectively. In vitro, the 38.5C-conditioned cells, relative to 37C, grew slightly faster. Compared to U87 cells, G55 cells demonstrated a greater response to the temperature difference. Hyperthermal culture markedly increased production of Hsp27 in most G55 cells, but only promoted transient expression of cancer stem cell marker CD133 in a small cell subpopulation. We subsequently transplanted G55 cells following 37C or 38.5C culture into the C2 or T10 spinal cord of adult female immunodeficient rats (3 rats/each locus/per temperature; total: 12 rats). Systematic analyses revealed that 38.5C-preconditioned G55 cells grew more malignantly at either C2 or T10 as determined by tumor size, outgrowth profile, resistance to bolus intratumor administration of 5-fluorouracil (0.1 mol), and posttumor survival (p0.05; n=6/group). Therefore, thermal preconditioning of glioma cells may be an effective way to influence the in vitro and in vivo oncological contour of glioma cells. Future studies are needed for assessing the potential oncogenic modifying effect of hyperthermia regimens on glioma cells.

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

    PubMed

    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 < 0.05), compared to 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 < 0.05), compared to docetaxel alone. Although our previous study showed that targeted delivery of VD3 reduced the rate of proliferation significantly (P < 0.05) in C6 glioma cells (a drug-resistant cell line), here we concluded that combinatorial therapy of exogenous VD3 with 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.

  5. MicroRNA-150 regulates glycolysis by targeting von Hippel-Lindau in glioma cells

    PubMed Central

    Li, Shi-Jie; Liu, Hong-Lin; Tang, Shi-Lei; Li, Xiao-Juan; Wang, Xiao-Yin

    2017-01-01

    Warburg effect, characterized by enhanced glycolysis and lactate production, even under aerobic conditions, is one of the hallmarks of cancer cells. However, the mechanism underlying this phenomenon remains poorly understood. Previous studies have shown that microRNA-150 (miR-150) is significantly up-regulated in various malignancies and represents a putative onco-miRNA in human cancers. In the present study, we aim to investigate the functional significance and molecular target of miR-150 in glioma. As a result, von Hippel-Lindau (VHL), which is a specific E3 ligase for hypoxia inducible factor 1 (HIF1α), was identified as a novel target of miR-150. Consistently, cells overexpressing miR-150 exhibited a metabolic shift, including enhanced glucose uptake and lactate production, which led to a rapid growth of glioma cells. Therefore, our results suggest that miR-150 modulates the Warburg effect in glioma via VHL/HIF1α and might provide a novel option for future treatments for glioma. PMID:28386333

  6. PP2A Inhibitor PME-1 Drives Kinase Inhibitor Resistance in Glioma Cells.

    PubMed

    Kaur, Amanpreet; Denisova, Oxana V; Qiao, Xi; Jumppanen, Mikael; Peuhu, Emilia; Ahmed, Shafiq U; Raheem, Olayinka; Haapasalo, Hannu; Eriksson, John; Chalmers, Anthony J; Laakkonen, Pirjo; Westermarck, Jukka

    2016-12-01

    Glioblastoma multiforme lacks effective therapy options. Although deregulated kinase pathways are drivers of malignant progression in glioblastoma multiforme, glioma cells exhibit intrinsic resistance toward many kinase inhibitors, and the molecular basis of this resistance remains poorly understood. Here, we show that overexpression of the protein phosphatase 2A (PP2A) inhibitor protein PME-1 drives resistance of glioma cells to various multikinase inhibitors. The PME-1-elicited resistance was dependent on specific PP2A complexes and was mediated by a decrease in cytoplasmic HDAC4 activity. Importantly, both PME-1 and HDAC4 associated with human glioma progression, supporting clinical relevance of the identified mechanism. Synthetic lethality induced by both PME-1 and HDAC4 inhibition was dependent on the coexpression of proapoptotic protein BAD. Thus, PME-1-mediated PP2A inhibition is a novel mechanistic explanation for multikinase inhibitor resistance in glioma cells. Clinically, these results may inform patient stratification strategies for future clinical trials with selected kinase inhibitors in glioblastoma multiforme. Cancer Res; 76(23); 7001-11. ©2016 AACR.

  7. ER-mitochondria contacts control surface glycan expression and sensitivity to killer lymphocytes in glioma stem-like cells.

    PubMed

    Bassoy, Esen Yonca; Kasahara, Atsuko; Chiusolo, Valentina; Jacquemin, Guillaume; Boydell, Emma; Zamorano, Sebastian; Riccadonna, Cristina; Pellegatta, Serena; Hulo, Nicolas; Dutoit, Valérie; Derouazi, Madiha; Dietrich, Pierre Yves; Walker, Paul R; Martinvalet, Denis

    2017-03-10

    Glioblastoma is a highly heterogeneous aggressive primary brain tumor, with the glioma stem-like cells (GSC) being more sensitive to cytotoxic lymphocyte-mediated killing than glioma differentiated cells (GDC). However, the mechanism behind this higher sensitivity is unclear. Here, we found that the mitochondrial morphology of GSCs modulates the ER-mitochondria contacts that regulate the surface expression of sialylated glycans and their recognition by cytotoxic T lymphocytes and natural killer cells. GSCs displayed diminished ER-mitochondria contacts compared to GDCs. Forced ER-mitochondria contacts in GSCs increased their cell surface expression of sialylated glycans and reduced their susceptibility to cytotoxic lymphocytes. Therefore, mitochondrial morphology and dynamism dictate the ER-mitochondria contacts in order to regulate the surface expression of certain glycans and thus play a role in GSC recognition and elimination by immune effector cells. Targeting the mitochondrial morphology, dynamism, and contacts with the ER could be an innovative strategy to deplete the cancer stem cell compartment to successfully treat glioblastoma.

  8. Cucurbitacin-I inhibits Aurora kinase A, Aurora kinase B and survivin, induces defects in cell cycle progression and promotes ABT-737-induced cell death in a caspase-independent manner in malignant human glioma cells.

    PubMed

    Premkumar, Daniel R; Jane, Esther P; Pollack, Ian F

    2015-01-01

    Because STAT signaling is commonly activated in malignant gliomas as a result of constitutive EGFR activation, strategies for inhibiting the EGFR/JAK/STAT cascade are of significant interest. We, therefore, treated a panel of established glioma cell lines, including EGFR overexpressors, and primary cultures derived from patients diagnosed with glioblastoma with the JAK/STAT inhibitor cucurbitacin-I. Treatment with cucurbitacin-I depleted p-STAT3, p-STAT5, p-JAK1 and p-JAK2 levels, inhibited cell proliferation, and induced G2/M accumulation, DNA endoreduplication, and multipolar mitotic spindles. Longer exposure to cucurbitacin-I significantly reduced the number of viable cells and this decrease in viability was associated with cell death, as confirmed by an increase in the subG1 fraction. Our data also demonstrated that cucurbitacin-I strikingly downregulated Aurora kinase A, Aurora kinase B and survivin. We then searched for agents that exhibited a synergistic effect on cell death in combination with cucurbitacin-I. We found that cotreatment with cucurbitacin-I significantly increased Bcl(-)2/Bcl(-)xL family member antagonist ABT-737-induced cell death regardless of EGFR/PTEN/p53 status of malignant human glioma cell lines. Although >50% of the cucurbitacin-I plus ABT-737 treated cells were annexin V and propidium iodide positive, PARP cleavage or caspase activation was not observed. Pretreatment of z-VAD-fmk, a pan caspase inhibitor did not inhibit cell death, suggesting a caspase-independent mechanism of cell death. Genetic inhibition of Aurora kinase A or Aurora kinase B or survivin by RNA interference also sensitized glioma cells to ABT-737, suggesting a link between STAT activation and Aurora kinases in malignant gliomas.

  9. PERK silence inhibits glioma cell growth under low glucose stress by blockage of p-AKT and subsequent HK2's mitochondria translocation.

    PubMed

    Hou, Xu; Liu, Yaohua; Liu, Huailei; Chen, Xin; Liu, Min; Che, Hui; Guo, Fei; Wang, Chunlei; Zhang, Daming; Wu, Jianing; Chen, Xiaofeng; Shen, Chen; Li, Chenguang; Peng, Fei; Bi, Yunke; Yang, Zhuowen; Yang, Guang; Ai, Jing; Gao, Xin; Zhao, Shiguang

    2015-03-12

    Glioma relies on glycolysis to obtain energy and sustain its survival under low glucose microenvironment in vivo. The mechanisms on glioma cell glycolysis regulation are still unclear. Signaling mediated by Double-stranded RNA-activated protein kinase (PKR) - like ER kinase (PERK) is one of the important pathways of unfolded protein response (UPR) which is comprehensively activated in cancer cells upon the hypoxic and low glucose stress. Here we show that PERK is significantly activated in human glioma tissues. PERK silencing results in decreased glioma cell viability and ATP/lactate production upon low glucose stress, which is mediated by partially blocked AKT activation and subsequent inhibition of Hexokinase II (HK2)'s mitochondria translocation. More importantly, PERK silenced glioma cells show decreased tumor formation capacity. Our results reveal that PERK activation is involved in glioma glycolysis regulation and may be a potential molecular target for glioma treatment.

  10. Differentiation-inducing effects of betamethasone on human glioma cell line U251.

    PubMed

    Jin, T; Wang, Y X; Fan, K; Tao, D B; Dong, X; Shen, J S

    2015-07-14

    We studied the differentiation-inducing effect of beta-methasone on human glioma cell line U251 cultured in vitro, and the underlying mechanism. U251 cells were divided into two groups: control group cells, cultured in Dulbecco's Modified Eagle's medium containing 10% fetal bovine serum; and medication group cells, treated with 15 μM betamethasone. Morphological cell changes were observed by inverted microscope, cell cycle changes were ascertained by flow cytometry, and vimentin expression was checked by immunocytochemistry. The expression levels of extracellular signal-regulated protein ki-nase (ERK), phosphorylated ERK (pERK), and glial fibrillary acidic protein (GFAP) were assessed by western blot. Compared with the control group, U251 cell processes increased significantly, but declined 96 h after betamethasone took effect. After 48 h, the percentage of S-phase cells decreased significantly (28.77 to 20.42%; P = 0.014); the percent-age of strongly positive vimentin cells decreased significantly (91 to 51%; P = 0.0092); and the ratio of expression of GFAP protein to the internal control β-actin increased significantly (0.24 to 0.53; P = 0.1). The level of ERK protein did not change significantly 48 and 96 h after the action of betamethasone, and the pERK/ERK ratios were 0.37 and 0.23, respectively, which were significantly reduced compared with the control group (P = 0.028 and 0.006). Betamethasone has a significant effect on the induction and differentiation of U251 cells, and its mechanism may be related to the inhibition of the abnormal activation of the ERK signal pathway.

  11. Characterizing nanoscale changes in the activity of VEGFR-2 on glioma microvascular endothelial cell membranes using atomic force microscopy

    PubMed Central

    Zhou, Dexiang; Zhan, Shengquan; Zhou, Dong; Wang, Peng; Chen, Guangzhong; Qin, Kun; Lin, Xiaofeng

    2017-01-01

    The aim of the current study was to demonstrate the distribution of VEGFR-2 on glioma microvascular endothelial cells on a nanoscale and investigate changes in VEGFR-2 activity following treatment with the VEGFR-2 inhibitor and agonist sorafenib and bradykinin, respectively. Three groups were evaluated in this study: Control glioma microvascular endothelial cells, sorafenib-treated glioma microvascular endothelial cells and bradykinin-treated glioma microvascular endothelial cells. Changes in the activity of VEGFR-2 on the glioma microvascular endothelial cell membranes following treatment with sorafenib and bradykinin were characterized by atomic force microscopy (AFM). Colloidal gold-labeled immune complexes and AFM were used to visualize the distribution of VEGFR-2 on the cell membranes. In the control group, VEGFR-2, which was observed as numerous globular structures, was evenly distributed on the cell surface membranes. The majority of the receptors were active. In the sorafenib group, only a few globular structures were observed on the cell membranes, with a density significantly lower than that in the control group (P<0.01). Furthermore, compared with the control group, fewer of the receptors were active. In the bradykinin group, numerous globular structures were densely distributed on the cell membranes, with a density significantly higher than that in the control group (P<0.01). The distribution and activity of VEGFR-2 on glioma microvascular endothelial cell membranes treated with sorafenib and bradykinin suggested that the activity of VEGFR-2 could be regulated by its inhibitor or agonist. PMID:28352319

  12. Glioma-derived macrophage migration inhibitory factor (MIF) promotes mast cell recruitment in a STAT5-dependent manner.

    PubMed

    Põlajeva, Jelena; Bergström, Tobias; Edqvist, Per-Henrik; Lundequist, Anders; Sjösten, Anna; Nilsson, Gunnar; Smits, Anja; Bergqvist, Michael; Pontén, Fredrik; Westermark, Bengt; Pejler, Gunnar; Forsberg Nilsson, Karin; Tchougounova, Elena

    2014-02-01

    Recently, glioma research has increased its focus on the diverse types of cells present in brain tumors. We observed previously that gliomas are associated with a profound accumulation of mast cells (MCs) and here we investigate the underlying mechanism. Gliomas express a plethora of chemoattractants. First, we demonstrated pronounced migration of human MCs toward conditioned medium from cultures of glioma cell lines. Subsequent cytokine array analyses of media from cells, cultured in either serum-containing or -free conditions, revealed a number of candidates which were secreted in high amounts in both cell lines. Among these, we then focused on macrophage migration inhibitory factor (MIF), which has been reported to be pro-inflammatory and -tumorigenic. Infiltration of MCs was attenuated by antibodies that neutralized MIF. Moreover, a positive correlation between the number of MCs and the level of MIF in a large cohort of human glioma tissue samples was observed. Further, both glioma-conditioned media and purified MIF promoted differential phosphorylation of a number of signaling molecules, including signal transducer and activator of transcription 5 (STAT5), in MCs. Inhibition of pSTAT5 signaling significantly attenuated the migration of MCs toward glioma cell-conditioned medium shown to contain MIF. In addition, analysis of tissue microarrays (TMAs) of high-grade gliomas revealed a direct correlation between the level of pSTAT5 in MCs and the level of MIF in the medium. In conclusion, these findings indicate the important influence of signaling cascades involving MIF and STAT5 on the recruitment of MCs to gliomas.

  13. Human neural stem cells transduced with IFN-beta and cytosine deaminase genes intensify bystander effect in experimental glioma.

    PubMed

    Ito, S; Natsume, A; Shimato, S; Ohno, M; Kato, T; Chansakul, P; Wakabayashi, T; Kim, S U

    2010-05-01

    Previously, we have shown that the genetically modified human neural stem cells (NSCs) show remarkable migratory and tumor-tropic capability to track down brain tumor cells and deliver therapeutic agents with significant therapeutic benefit. Human NSCs that were retrovirally transduced with cytosine deaminase (CD) gene showed remarkable 'bystander killer effect' on the glioma cells after application of the prodrug, 5-fluorocytosine (5-FC). Interferon-beta (IFN-beta) is known for its antiproliferative effects in a variety of cancers. In our pilot clinical trial in glioma, the IFN-beta gene has shown potent antitumor activity in patients with malignant glioma. In the present study, we sought to examine whether human NSCs genetically modified to express both CD and IFN-beta genes intensified antitumor effect on experimental glioma. In vitro studies showed that CD/IFN-beta-expressing NSCs exerted a remarkable bystander effect on human glioma cells after the application of 5-FC, as compared with parental NSCs and CD-expressing NSCs. In animal models with human glioma orthotopic xenograft, intravenously infused CD/IFN-beta-expressing NSCs produced striking antitumor effect after administration of the prodrug 5-FC. Furthermore, the same gene therapy regimen prolonged survival periods significantly in the experimental animals. The results of the present study indicate that the multimodal NSC-based treatment strategy might have therapeutic potential against gliomas.

  14. Bradykinin enhances invasion of malignant glioma into the brain parenchyma by inducing cells to undergo amoeboid migration

    PubMed Central

    Seifert, Stefanie; Sontheimer, Harald

    2014-01-01

    Abstract The molecular and cellular mechanisms governing cell motility and directed migration in response to the neuropeptide bradykinin are largely unknown. Here, we demonstrate that human glioma cells whose migration is guided by bradykinin generate bleb-like protrusions. We found that activation of the B2 receptor leads to a rise in free Ca2+ from internal stores that activates actomyosin contraction and subsequent cytoplasmic flow into protrusions forming membrane blebs. Furthermore Ca2+ activates Ca2+-dependent K+ and Cl− channels, which participate in bleb regulation. Treatment of gliomas with bradykinin in situ increased glioma growth by increasing the speed of cell migration at the periphery of the tumour mass. To test if bleb formation is related to bradykinin-promoted glioma invasion we blocked glioma migration with blebbistatin, a blocker of myosin kinase II, which is necessary for proper bleb retraction. Our findings suggest a pivotal role of bradykinin during glioma invasion by stimulating amoeboid migration of glioma cells. PMID:25194042

  15. Dendritic Cell Based Vaccines that Utilize Myeloid Rather than Plasmacytoid Cells Offer a Superior Survival Advantage in Malignant Glioma

    PubMed Central

    Dey, Mahua; Chang, Alan L.; Miska, Jason; Wainwright, Derek A.; Ahmed, Atique U.; Balyasnikova, Irina V.; Pytel, Peter; Han, Yu; Tobias, Alex; Zhang, Lingjiao; Qiao, Jian; Lesniak, Maciej S.

    2015-01-01

    Dendritic cells (DC) are professional antigen presenting cells (APC) that are traditionally divided into two distinct subsets: myeloid DC (mDCs) and plasmacytoid DC (pDCs). pDCs are known for their ability to secrete large amount of IFN-α. Apart from IFN-α production, pDCs can also process antigen and induce T-cell immunity or tolerance. In several solid tumors, pDCs have been shown to play a critical role in promoting tumor immunosuppression. We investigated the role of pDCs in the process of glioma progression in the syngeneic murine model of glioma. We show that glioma-infiltrating pDCs are the major APC in glioma and are deficient in IFN-α secretion (p < 0.05). pDC depletion leads to increased survival of the mice bearing intracranial tumor by decreasing the number of regulatory T-cells (Treg) and by decreasing the suppressive capabilities of Tregs. We subsequently compared the ability of mDCs and pDCs to generate effective anti-glioma immunity in a GL261-OVA mouse model of glioma. Our data suggest that mature pDCs and mDCs isolated from naïve mice can be effectively activated and loaded with SIINFEKL antigen in vitro. Upon intra-dermal injection in the hind leg, a fraction of both types of DCs migrate to the brain and lymph nodes.. Compared to mice vaccinated with pDC or control mice, mice vaccinated with mDCs generated a robust Th1 type immune response, characterized by high frequency of CD4+Tbet+ T-cells and CD8+Siinfekel+ T-cells. This robust anti-tumor T-cell response resulted in tumor eradication and long-term survival in 60% of the animals (p<0.001). PMID:26026061

  16. A dual PI3K/mTOR inhibitor, PI-103, cooperates with stem cell-delivered TRAIL in experimental glioma models.

    PubMed

    Bagci-Onder, Tugba; Wakimoto, Hiroaki; Anderegg, Maarten; Cameron, Cody; Shah, Khalid

    2011-01-01

    The resistance of glioma cells to a number of antitumor agents and the highly invasive nature of glioma cells that escape the primary tumor mass are key impediments to the eradication of tumors in glioma patients. In this study, we evaluated the therapeutic efficacy of a novel PI3-kinase/mTOR inhibitor, PI-103, in established glioma lines and primary CD133(+) glioma-initiating cells and explored the potential of combining PI-103 with stem cell-delivered secretable tumor necrosis factor apoptosis-inducing ligand (S-TRAIL) both in vitro and in orthotopic mouse models of gliomas. We show that PI-103 inhibits proliferation and invasion, causes G(0)-G(1) arrest in cell cycle, and results in significant attenuation of orthotopic tumor growth in vivo. Establishing cocultures of neural stem cells (NSC) and glioma cells, we show that PI-103 augments the response of glioma cells to stem cell-delivered S-TRAIL. Using bimodal optical imaging, we show that when different regimens of systemic PI-103 delivery are combined with NSC-derived S-TRAIL, a significant reduction in tumor volumes is observed compared with PI-103 treatment alone. To our knowledge, this is the first study that reveals the antitumor effect of PI-103 in intracranial gliomas. Our findings offer a preclinical rationale for application of mechanism-based systemically delivered antiproliferative agents and novel stem cell-based proapoptotic therapies to improve treatment of malignant gliomas.

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

    PubMed

    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. Carbon Ion Irradiation Inhibits Glioma Cell Migration Through Downregulation of Integrin Expression

    SciTech Connect

    Rieken, Stefan; Habermehl, Daniel; Wuerth, Lena; Brons, Stephan; Mohr, Angela; Lindel, Katja; Weber, Klaus; Haberer, Thomas; Debus, Juergen; Combs, Stephanie E.

    2012-05-01

    Purpose: To investigate the effect of carbon ion irradiation on glioma cell migration. Methods and Materials: U87 and Ln229 glioma cells were irradiated with photons and carbon ions. Migration was analyzed 24 h after irradiation. Fluorescence-activated cell sorting analysis was performed in order to quantify surface expression of integrins. Results: Single photon doses of 2 Gy and 10 Gy enhanced {alpha}{sub {nu}}{beta}{sub 3} and {alpha}{sub {nu}}{beta}{sub 5} integrin expression and caused tumor cell hypermigration on both vitronectin (Vn) and fibronectin (Fn). Compared to integrin expression in unirradiated cells, carbon ion irradiation caused decreased integrin expression and inhibited cell migration on both Vn and Fn. Conclusion: Photon radiotherapy (RT) enhances the risk of tumor cell migration and subsequently promotes locoregional spread via photon induction of integrin expression. In contrast to photon RT, carbon ion RT causes decreased integrin expression and suppresses glioma cell migration on both Vn and Fn, thus promising improved local control.

  19. Effects of morphine on testosterone levels in rat C6 glioma cells: modulation by anastrozole.

    PubMed

    Ceccarelli, Ilaria; Rossi, Antonella; Maddalena, Melinda; Weber, Elisabetta; Aloisi, Anna Maria

    2009-10-01

    Rat C6 glioma cells are commonly used to investigate the functions of glial cells. To evaluate the presence of testosterone and its metabolism in rat C6 glioma cells, we cultured them in media with or without the addition of testosterone propionate and anastrozole, a blocker of aromatase, the enzyme needed to transform testosterone into estradiol. The same procedure was repeated with morphine (10 and 100 microM), known to decrease testosterone levels in the brain (in rats) and plasma (in rats and humans). Confluent cells were exposed to the test media for 48 h and then collected. Cell pellets were used to determine testosterone by radioimmunoassay. The C6 cells contained detectable levels of testosterone and the levels increased with the addition of testosterone to the medium. Aromatase blockage by anastrozole increased cellular levels of testosterone regardless of the addition of exogenous testosterone. Both concentrations of morphine dose-dependently decreased testosterone levels in the C6 cells; this effect was also present with the contemporary administration of anastrozole. Our findings show that testosterone is present in rat C6 glioma cells and can be metabolized by aromatase. Moreover, the presence of morphine in the culture medium strongly decreased testosterone, demonstrating that the glia would be a target of the morphine-induced hypogonadal effect.

  20. PAR1 inhibition suppresses the self-renewal and growth of A2B5-defined glioma progenitor cells and their derived gliomas in vivo

    PubMed Central

    Auvergne, R; Wu, C; Connell, A; Au, S; Cornwell, A; Osipovitch, M; Benraiss, A; Dangelmajer, S; Guerrero-Cazares, H; Quinones-Hinojosa, A; Goldman, SA

    2016-01-01

    Glioblastoma (GBM) remains the most common and lethal intracranial tumor. In a comparison of gene expression by A2B5-defined tumor-initiating progenitor cells (TPCs) to glial progenitor cells derived from normal adult human brain, we found that the F2R gene encoding PAR1 was differentially overexpressed by A2B5-sorted TPCs isolated from gliomas at all stages of malignant development. In this study, we asked if PAR1 is causally associated with glioma progression. Lentiviral knockdown of PAR1 inhibited the expansion and self-renewal of human GBM-derived A2B5+ TPCs in vitro, while pharmacological inhibition of PAR 1 similarly slowed both the growth and migration of A2B5+ TPCs in culture. In addition, PAR1 silencing potently suppressed tumor expansion in vivo, and significantly prolonged the survival of mice following intracranial transplantation of human TPCs. These data strongly suggest the importance of PAR1 to the self-renewal and tumorigenicity of A2B5-defined glioma TPCs; as such, the abrogation of PAR1-dependent signaling pathways may prove a promising strategy for gliomas. PMID:26616854

  1. Role of lymphocyte-specific protein tyrosine kinase (LCK) in the expansion of glioma-initiating cells by fractionated radiation

    SciTech Connect

    Kim, Rae-Kwon; Yoon, Chang-Hwan; Hyun, Kyung-Hwan; Lee, Hyejin; An, Sungkwan; Park, Myung-Jin; Kim, Min-Jung; Lee, Su-Jae

    2010-11-26

    Research highlights: {yields} Activation of Lymphocyte-specific protein tyrosine kinase (LCK) is involved in the fractionated radiation-induced expansion of glioma stem-like cells. {yields} Inhibition of LCK prevents acquisition of fractionated radiation-induced resistance to chemotherapeutic treatment. {yields} LCK activity is critical for the maintenance of self-renewal in glioma stem-like cells. -- Abstract: Brain cancers frequently recur or progress as focal masses after treatment with ionizing radiation. Radiation used to target gliomas may expand the cancer stem cell population and enhance the aggressiveness of tumors; however, the mechanisms underlying the expansion of cancer stem cell population after radiation have remained unclear. In this study, we show that LCK (lymphocyte-specific protein tyrosine kinase) is involved in the fractionated radiation-induced expansion of the glioma-initiating cell population and acquisition of resistance to anticancer treatments. Fractionated radiation caused a selective increase in the activity of LCK, a Src family non-receptor tyrosine kinase. The activities of other Src family kinases Src, Fyn, and Lyn were not significantly increased. Moreover, knockdown of LCK expression with a specific small interfering RNA (siRNA) effectively blocked fractionated radiation-induced expansion of the CD133{sup +} cell population. siRNA targeting of LCK also suppressed fractionated radiation-induced expression of the glioma stem cell marker proteins CD133, Nestin, and Musashi. Expression of the known self-renewal-related proteins Notch2 and Sox2 in glioma cells treated with fractionated radiation was also downregulated by LCK inhibition. Moreover, siRNA-mediated knockdown of LCK effectively restored the sensitivity of glioma cells to cisplatin and etoposide. These results indicate that the non-receptor tyrosine kinase LCK is critically involved in fractionated radiation-induced expansion of the glioma-initiating cell population and

  2. Capsaicin and dihydrocapsaicin induce apoptosis in human glioma cells via ROS and Ca2+-mediated mitochondrial pathway

    PubMed Central

    Xie, Le; Xiang, Guang-Hong; Tang, Tao; Tang, Yan; Zhao, Ling-Yun; Liu, Dong; Zhang, You-Ren; Tang, Jin-Tian; Zhou, Shen; Wu, Da-Hua

    2016-01-01

    Human glioma is the most common type of primary brain tumor and one of the most invasive and aggressive tumors, which, even with treatments including surgery, radiotherapy and chemotherapy, often relapses and exhibits resistance to conventional treatment methods. Developing novel strategies to control human glioma is, therefore, an important research focus. The present study investigated the mechanism of apoptosis induction in U251 human glioma cells by capsaicin (Cap) and dihydrocapsaicin (DHC), the major pungent ingredients of red chili pepper, using the Cell Counting Kit-8 assay, transmission electron microscopy analysis, flow cytometry analysis, laser scanning confocal microscope analysis and immunohistochemical staining. Treatment of U251 glioma cells with Cap and DHC resulted in a dose- and time-dependent inhibition of cell viability and induction of apoptosis, whereas few effects were observed on the viability of L929 normal murine fibroblast cells. The apoptosis-inducing effects of Cap and DHC in U251 cells were associated with the generation of reactive oxygen species, increased Ca2+ concentrations, mitochondrial depolarization, release of cytochrome c into the cytosol and activation of caspase-9 and −3. These effects were further confirmed by observations of the anti-tumor effects of Cap and DHC in vivo in a U251 cell murine tumor xenograft model. These results demonstrate that Cap and DHC are effective inhibitors of in vitro and in vivo survival of human glioma cells, and provide the rationale for further clinical investigation of Cap and DHC as treatments for human glioma. PMID:27748914

  3. Biphasic Dependence of Glioma Survival and Cell Migration on CD44 Expression Level.

    PubMed

    Klank, Rebecca L; Decker Grunke, Stacy A; Bangasser, Benjamin L; Forster, Colleen L; Price, Matthew A; Odde, Thomas J; SantaCruz, Karen S; Rosenfeld, Steven S; Canoll, Peter; Turley, Eva A; McCarthy, James B; Ohlfest, John R; Odde, David J

    2017-01-03

    While several studies link the cell-surface marker CD44 to cancer progression, conflicting results show both positive and negative correlations with increased CD44 levels. Here, we demonstrate that the survival outcomes of genetically induced glioma-bearing mice and of high-grade human glioma patients are biphasically correlated with CD44 level, with the poorest outcomes occurring at intermediate levels. Furthermore, the high-CD44-expressing mesenchymal subtype exhibited a positive trend of survival with increased CD44 level. Mouse cell migration rates in ex vivo brain slice cultures were also biphasically associated with CD44 level, with maximal migration corresponding to minimal survival. Cell simulations suggest that cell-substrate adhesiveness is sufficient to explain this biphasic migration. More generally, these results highlight the potential importance of non-monotonic relationships between survival and biomarkers associated with cancer progression.

  4. Standard of care therapy for malignant glioma and its effect on tumor and stromal cells.

    PubMed

    Jones, T S; Holland, E C

    2012-04-19

    Glioblastoma is the most common and deadly of the primary central nervous system tumors. Recent advances in molecular characterization have subdivided these tumors into at least three main groups. In addition, these tumors are cellularly complex with multiple stromal cell types contributing to the biology of the tumor and treatment response. Because essentially all glioma patients are treated with radiation, various chemotherapies and steroids, the tumor that finally kills them has been modified by these treatments. Most of the investigation of the effects of therapy on these tumors has focused on the glioma cells per se. However, despite the importance of the stromal cells in these tumors, little has been done to understand the effects of treatment on stromal cells and their contribution to disease. Understanding how current standard therapy affects the biology of the tumor and the tumor stroma may provide insight into the mechanisms that are important to the inhibition of tumor growth as well as the biology of recurrent tumors.

  5. Reporter gene imaging of targeted T cell immunotherapy in recurrent glioma.

    PubMed

    Keu, Khun Visith; Witney, Timothy H; Yaghoubi, Shahriar; Rosenberg, Jarrett; Kurien, Anita; Magnusson, Rachel; Williams, John; Habte, Frezghi; Wagner, Jamie R; Forman, Stephen; Brown, Christine; Allen-Auerbach, Martin; Czernin, Johannes; Tang, Winson; Jensen, Michael C; Badie, Behnam; Gambhir, Sanjiv S

    2017-01-18

    High-grade gliomas are aggressive cancers that often become rapidly fatal. Immunotherapy using CD8(+) cytotoxic T lymphocytes (CTLs), engineered to express both herpes simplex virus type 1 thymidine kinase (HSV1-TK) and interleukin-13 (IL-13) zetakine chimeric antigen receptor (CAR), is a treatment strategy with considerable potential. To optimize this and related immunotherapies, it would be helpful to monitor CTL viability and trafficking to glioma cells. We show that noninvasive positron emission tomography (PET) imaging with 9-[4-[(18)F]fluoro-3-(hydroxymethyl)butyl]guanine ([(18)F]FHBG) can track HSV1-tk reporter gene expression present in CAR-engineered CTLs. [(18)F]FHBG imaging was safe and enabled the longitudinal imaging of T cells stably transfected with a PET reporter gene in patients. Further optimization of this imaging approach for monitoring in vivo cell trafficking should greatly benefit various cell-based therapies for cancer.

  6. Corticosterone Inhibits the Proliferation of C6 Glioma Cells via the Translocation of Unphosphorylated Glucocorticoid Receptor.

    PubMed

    Nakatani, Yoshihiko; Amano, Taku; Takeda, Hiroshi

    2016-01-01

    Astroglial cells have been considered to have passive brain function by helping to maintain neurons. However, recent studies have revealed that the dysfunction of such passive functions may be associated with various neuropathological diseases, such as schizophrenia, Alzheimer's disease, amyotrophic lateral sclerosis and major depression. Corticosterone (CORT), which is often referred to as the stress hormone, is a well-known regulator of peripheral immune responses and also shows anti-inflammatory properties in the brain. However, it is still obscure how CORT affects astroglial cell function. In this study, we investigated the effects of CORT on the proliferation and survival of astroglial cells using C6 glioma cells. Under treatment with CORT for 24h, the proliferation of C6 glioma cells decreased in a dose-dependent manner. Moreover, this inhibition was diminised by treatment with mifepristone, a glucocorticoid receptor (GR) antagonist, but not by spironolactone, a mineralocorticoid receptor (MR) antagonist, and was independent of GR phosphorylation and other GR-related intracellular signaling cascades. Furthermore, it was observed that the translocation of GR from the cytosol to the nucleus was promoted by the treatment with CORT. These results indicate that CORT decreases the proliferation of C6 glioma cells by modifying the transcription of a particular gene related to cell proliferation independent of GR phosphorylation.

  7. Nano Size Effects of TiO2 Nanotube Array on the Glioma Cells Behavior

    PubMed Central

    Yang, He; Qin, Xiaofei; Tian, Ang; Zhang, Dongyong; Xue, Xiangxin; Wu, Anhua

    2013-01-01

    In order to investigate the interplay between the cells and TiO2 nanotube array, and to explore the ability of cells to sense the size change in nano-environment, we reported on the behavior of glioma C6 cells on nanotube array coatings in terms of proliferation and apoptosis. The behavior of glioma C6 cells was obviously size-dependent on the coatings; the caliber with 15 nm diameter provided effective spacing to improve the cells proliferation and enhanced the cellular activities. C6 cells’ biological behaviors showed many similar tendencies to many phorocytes; the matching degree of geometry between nanotube and integrin defined that a spacing of 15 nm was optimal for inducing signals to nucleus, which results in achieving maximum activity of glioma cells. In addition, the immune behavior of cells was studied, a variety of inflammatory mediator’s gene expression levels were controlled by the nanoscale dimension, the expressions of IL-6 and IL-10 were higher on 30 nm than on 15 nm nanotube. PMID:23344031

  8. Antitumor efficacy of argon-helium cryoablation-generated dendritic cell vaccine in glioma.

    PubMed

    Yin, Zhilin; Lu, Guohui; Xiao, Zhenyong; Liu, Tianzhu; He, Xiaozheng; Wang, Qifu; Lin, Chunnan; Zhang, Shizhong

    2014-03-05

    Dendritic cells (DCs) are potent antigen-presenting cells that play a critical role in priming tumor immune responses. We investigated the mechanisms of antitumor efficacy of DCs pulsed with argon-helium-cryotreated glioma cells. There was significant upregulation of maturation markers (CD80, CD86, MHC-I, and MHC-II) in argon-helium freeze-thawed lysate-pulsed DCs. The concentration of interleukin-6 (IL-6), IL-1β, tumor necrosis factor-α, and IL-12 secreted by lysate-pulsed DCs was increased. The concentration of interferon-γ secreted by T cells stimulated by lysate-pulsed DCs was increased. The cytotoxicity assay showed that T cells stimulated by lysate-pulsed DCs could kill glioma cells significantly more effectively. Our results suggest that argon-helium freeze-thawed lysate-pulsed DCs in vitro can promote DC maturation and enhance DC antigen-presenting function, and induce cytotoxic T lymphocytes to kill tumor cells. Therefore, the combination of argon-helium cryoablation and DC vaccine may represent a novel treatment method for glioma.

  9. Ectopic expression of AP-2α transcription factor suppresses glioma progression.

    PubMed

    Su, Wenjing; Xia, Juan; Chen, Xueqin; Xu, Miao; Nie, Ling; Chen, Ni; Gong, Jing; Li, Xinglan; Zhou, Qiao

    2014-01-01

    The transcriptional factor AP-2α is a tumor suppressor gene and is downregulated in various neoplasms including glioma. Although the level of AP-2α is negatively associated with the grade of human glioma, the specific functions of AP-2α in glioma are still unknown. In this study, we experimentally showed that artificial overexpression of AP-2α in glioma T98G and U251 cells significantly downregulated the mRNA levels of Bcl-xl, Bcl-2, c-IAP2 and survivin, together with upregulation of the Hrk mRNA levels. Reintroduction of AP-2α also induced downregulation of the protein levels of survivin and VEGF in glioma cells. In biological assays with T98G and U251 cells, AP-2α reduced tumor cell growth, increased cell death, attenuated cell migration and endothelial tube formation. The AP-2α transcription factor may play an important role in suppressing glioma progression.

  10. Involvement of the neural stem cell compartment by pediatric and adult gliomas: a retrospective review of 377 cases.

    PubMed

    Marsh, James C; Goldman, Stewart; Ziel, Ellis; Bregman, Corey; Diaz, Aidnag; Byrne, Richard; Fangusaro, Jason

    2015-03-01

    To assess frequency of neural stem cell compartment (NSC) involvement in adult and pediatric gliomas [World Health Organization (WHO) grades 1-4], and to assess whether NSC involvement at presentation impacts on survival, recurrence rates, and/or transformation from low grade (WHO grade 1-2) to high grade disease (WHO grades 3-4). Cranial MRIs for 154 pediatric and 223 adult glioma patients treated from 2000 to 2012 were reviewed. NSC involvement was documented. Tumors were stratified by age (adult vs. pediatric), histology, tumor grade, tumor location, and involvement of midline structures. Odds ratios (OR) for death were calculated based on NSC status at presentation. Rates of transformation and recurrence rates (ORR) were compared using Fisher's Exact Test. Time to recurrence (TTR) was calculated using student t test. Among recurrent and transformed tumors, we also assessed the rate of NSC involvement at time of recurrence or transformation. 74.8 % of tumors had NSC involvement. Higher rates of NSC involvement were seen among adult (p = .0001); high grade (p = .0001)); grade 2 versus grade 1 (p = .0001) and other grade 1 histologies (p = .0001) versus JPA (juvenile pilocytic astrocytoma) patients); grade 2-4 tumors (p = .0001); and supratentorial tumors (p < .0001). No transformation was noted among pediatric low grade tumors or adult grade 1 tumors. 22/119 (18.5 %) adult grade 2 tumors transformed. Rates of transformation were not impacted by NSC status (p = .47). ORR was 15.1 %, and was greater for NSC+ tumors at presentation (p = .05). 36/41 recurrences (87.8 %) involved NSC at time of recurrence. OR for death was 2.62 (1.16-5.9), p = .02 for NSC+ tumors at presentation. Adult and pediatric gliomas (all grades) frequently involve NSC at presentation, although rates are lower in pediatric JPA and all infratentorial tumors. NSC involvement at presentation increases OR death and reduces TTR for pediatric gliomas (all grades) and adult low grade gliomas, and

  11. Gene expression profile induced by BCNU in human glioma cell lines with differential MGMT expression.

    PubMed

    Bandres, Eva; Andion, Esther; Escalada, Alvaro; Honorato, Beatriz; Catalan, Victoria; Cubedo, Elena; Cordeu, Lucia; Garcia, Fermin; Zarate, Ruth; Zabalegui, Natalia; Garcia-Foncillas, Jesus

    2005-07-01

    Chemotherapy with the alkylating agent BCNU (1,3-bis (2-chloroethyl)-1-nitrosourea) is the most commonly used chemotherapeutic agent for gliomas. However, the usefulness of this agent is limited because tumor cell resistance to BCNU is frequently found in clinical brain tumor therapy. The O6-methylguanine-DNA methyltransferase protein (MGMT) reverses alkylation at the O6 position of guanine and we have reported the role of MGMT in the response of brain tumors to alkylating agents. However, the different mechanisms underlying the patterns related to MGMT remain unclear. To better understand the molecular mechanism by which BCNU exerts its effect in glioma cell lines according MGMT expression, we used microarray technology to interrogate 3800 known genes and determine the gene expression profiles altered by BCNU treatment. Our results showed that treatment with BCNU alters the expression of a diverse group of genes in a time-dependent manner. A subset of gene changes was found common in both glioma cell lines and other subset is specific of each cell line. After 24 h of BCNU treatment, up-regulation of transcription factors involved in the nucleation of both RNA polymerase II and III transcription initiation complexes was reported. Interestingly, BCNU promoted the expression of actin-dependent regulators of chromatin. Similar effects were found with higher BCNU doses in MGMT+ cell line showing a similar mechanism that in MGMT-deficient cell with standard doses. Our data suggest that human glioma cell lines treated with BCNU, independently of MGMT expression, show changes in the expression of cell cycle and survival-related genes interfering the transcription mechanisms and the chromatin regulation.

  12. SRL-Coated PAMAM Dendrimer Nano-Carrier for Targeted Gene Delivery to the Glioma Cells and Competitive Inhibition by Lactoferrin

    PubMed Central

    zarebkohan, Amir; Najafi, Farhood; Moghimi, Hamid Reza; Hemmati, Mohammad; Deevband, Mohammad Reza; Kazemi, Bahram

    2016-01-01

    Glioma, as a primary tumor of central nervous system, is the main cause of death in patients with brain cancer. Therefore, development of an efficient strategy for treatment of glioma is worthy. The aim of the current study was to develop a SRL peptide-coated dendrimer as a novel dual gene delivery system for targeting the LRP receptor, an up-regulated gene in both BBB and glioma cells. To perform this investigation, our newly developed nanocarrier (PAMAM-PEG-SRL) was used for gene delivery to C6 glioma cell lines. DNA (GFP) was loaded in these functionalized nanoparticles and their cellular uptake/distribution and gene transfection efficacy was evaluated by fluorescence and confocal microscopy. In vitro studies showed that SRL-modified nanoparticles have good transfection efficacy. Results revealed improved gene transfection efficiency of newly-synthesized delivery system. We also found that lactoferrin, as a LRP ligand, reduced the gene transfection efficacy of the delivery system due to its higher affinity compared to SRL peptides (Competitive inhibition). The present results suggest that the synthesized delivery system has the potential to be used as an alternative targeted drug delivery system for brain tumors. PMID:28243262

  13. PTEN-induction in U251 glioma cells decreases the expression of insulin-like growth factor binding protein-2

    SciTech Connect

    Levitt, Randy J.; Georgescu, Maria-Magdalena; Pollak, Michael . E-mail: michael.pollak@mcgill.ca

    2005-11-04

    PTEN is a tumor suppressor gene whose loss of function is observed in {approx}40-50% of human cancers. Although insulin-like growth factor binding protein-2 (IGFBP-2) was classically described as a growth inhibitor, multiple recent reports have shown an association of overexpression and/or high serum levels of IGFBP-2 with poor prognosis of several malignancies, including gliomas. Using an inducible PTEN expression system in the PTEN-null glioma cell line U251, we demonstrate that PTEN-induction is associated with reduced proliferation, increased apoptosis, and a substantial reduction of the high levels of IGFBP-2 expression. The PTEN-induced decrease in IGFBP-2 expression could be mimicked with the PI3-kinase inhibitor LY294002, indicating that the lipid phosphatase activity of PTEN is responsible for the observed effect. However, the rapamycin analog CCI-779 did not affect IGFBP-2 expression, suggesting that the PTEN-induced decrease in IGFBP-2 expression is not attributable to decreased mTOR signalling. Recombinant human IGFBP-2 was unable to rescue U251-PTEN cells from the antiproliferative effects of PTEN, and IGFBP-2 siRNA did not affect the IGF-dependent or -independent growth of this cell line. These results suggest that the clinical data linking IGFBP-2 expression to poor prognosis may arise, at least in part, because high levels of IGFBP-2 expression correlate with loss of function of PTEN, which is well known to lead to aggressive behavior of gliomas. Our results motivate translational research regarding the relationship between IGFBP-2 expression and loss of function of PTEN.

  14. MiR-101 reverses the hypomethylation of the LMO3 promoter in glioma cells

    PubMed Central

    Yu, Zhibin; Xu, Gang; Tang, Hailin; Wang, Wei; Wang, Zeyou; Li, Guiyuan; Wu, Minghua

    2015-01-01

    LIM-only protein 3 (LMO3), a member of the LIM-only protein group, is a new DNA methylation gene that was identified in gliomas via the MeDIP-Chip in our previous study. In this study, we found that LIM-only protein 3 (LMO3) is hypomethylated and overexpressed in glioma cells and tissues. The overexpression of LMO3 was correlated with a poor prognosis in glioma patients, and LMO3 was indirectly inhibited by the tumor suppressor miR-101, which is a potential prognosis marker of gliomas. MiR-101 decreased the expression of LMO3 by reversing the methylation status of the LMO3 promoter and by inhibiting the presence of the methylation-related histones H3K4me2 and H3K27me3 and increasing the presence of H3K9me3 and H4K20me3 on the promoter. It was determined that miR-101 decreases the occupancy of H3K27me3 by inhibiting EZH2, DNMT3A and EED and decreases the H3K9me3 occupancy on the LMO3 promoter via SUV39H1, SUV39H2, G9a and PHF8. Furthermore, miR-101 suppresses the expression of LMO3 by decreasing USF and MZF1. PMID:25829251

  15. Control of cell proliferation in human glioma by glucocorticoids.

    PubMed

    Freshney, R I; Sherry, A; Hassanzadah, M; Freshney, M; Crilly, P; Morgan, D

    1980-06-01

    Survival and proliferation of cell cultures from human anaplastic astrocytomas were shown to be enhanced by glucocorticoids with an optimal concentration of approximately 2.5 x 10(-5)M (10 micrograms/ml). The stimulation of proliferation was only observed in a clonal growth assay and was reversed as the size of individual colonies reached approximately 50 cells. Above this size, and in regular monolayer cultures, glucocorticoids were found to inhibit cell proliferation as measured by direct cell counting and incorporation of [3H] thymidine. Cultures grown to maximum cell densities in non-limiting medium conditions reached a lower terminal cell density, and had a reduced labelling index with [3H] thymidine in the presence of glucocorticoids. Although there was little difference between the actions of beta-methasone, dexamethasone and ethyl prednisolone, methyl prednisolone was found to be more effective, both in terms of stimulation of clonal growth and inhibition of growth at high cell densities. There was no evidence of cytotoxicity with glucocorticoids up to 5 x 10(-5)M (20 micrograms/ml) and it is suggested that glucocorticoids act via a normal regulatory process, perhaps enhancing cell-cell recognition.

  16. Control of cell proliferation in human glioma by glucocorticoids.

    PubMed Central

    Freshney, R. I.; Sherry, A.; Hassanzadah, M.; Freshney, M.; Crilly, P.; Morgan, D.

    1980-01-01

    Survival and proliferation of cell cultures from human anaplastic astrocytomas were shown to be enhanced by glucocorticoids with an optimal concentration of approximately 2.5 x 10(-5)M (10 micrograms/ml). The stimulation of proliferation was only observed in a clonal growth assay and was reversed as the size of individual colonies reached approximately 50 cells. Above this size, and in regular monolayer cultures, glucocorticoids were found to inhibit cell proliferation as measured by direct cell counting and incorporation of [3H] thymidine. Cultures grown to maximum cell densities in non-limiting medium conditions reached a lower terminal cell density, and had a reduced labelling index with [3H] thymidine in the presence of glucocorticoids. Although there was little difference between the actions of beta-methasone, dexamethasone and ethyl prednisolone, methyl prednisolone was found to be more effective, both in terms of stimulation of clonal growth and inhibition of growth at high cell densities. There was no evidence of cytotoxicity with glucocorticoids up to 5 x 10(-5)M (20 micrograms/ml) and it is suggested that glucocorticoids act via a normal regulatory process, perhaps enhancing cell-cell recognition. Images Fig. 2 Fig. 3 PMID:7426310

  17. Dendritic cell immunotherapy versus bevacizumab plus irinotecan in recurrent malignant glioma patients: a survival gain analysis

    PubMed Central

    Artene, Stefan-Alexandru; Turcu-Stiolica, Adina; Hartley, Richard; Ciurea, Marius Eugen; Daianu, Oana; Brindusa, Corina; Alexandru, Oana; Tataranu, Ligia Gabriela; Purcaru, Stefana Oana; Dricu, Anica

    2016-01-01

    Background The bevacizumab and irinotecan protocol is considered a standard treatment regimen for recurrent malignant glioma. Recent advances in immunotherapy have hinted that vaccination with dendritic cells could become an alternative salvage therapy for the treatment of recurrent malignant glioma. Methods A search was performed on PubMed, Cochrane Library, Web of Science, ScienceDirect, and Embase in order to identify studies with patients receiving bevacizumab plus irinotecan or dendritic cell therapy for recurrent malignant gliomas. The data obtained from these studies were used to perform a systematic review and survival gain analysis. Results Fourteen clinical studies with patients receiving either bevacizumab plus irinotecan or dendritic cell vaccination were identified. Seven studies followed patients that received bevacizumab plus irinotecan (302 patients) and seven studies included patients that received dendritic cell immunotherapy (80 patients). For the patients who received bevacizumab plus irinotecan, the mean reported median overall survival was 7.5 (95% confidence interval [CI] 4.84–10.16) months. For the patients who received dendritic cell immunotherapy, the mean reported median overall survival was 17.9 (95% CI 11.34–24.46) months. For irinotecan + bevacizumab group, the mean survival gain was −0.02±2.00, while that for the dendritic cell immunotherapy group was −0.01±4.54. Conclusion For patients with recurrent malignant gliomas, dendritic cell immunotherapy treatment does not have a significantly different effect when compared with bevacizumab and irinotecan in terms of survival gain (P=0.535) and does not improve weighted survival gain (P=0.620). PMID:27877052

  18. β-catenin knockdown inhibits the proliferation of human glioma cells in vitro and in vivo

    PubMed Central

    WANG, ZHONG; CHEN, QIANXUE

    2016-01-01

    β-catenin is a crucial oncogene that is capable of regulating cancer progression. The aim of the present study was to clarify whether β-catenin was associated with the proliferation and progress of glioma. In order to knockdown the expression of β-catenin in human U251 glioma cells, three pairs of small interfering (si)RNA were designed and synthesized and the most effective siRNA was selected and used for silencing the endogenous β-catenin, which was detected by western blot analysis and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Proliferation was subsequently detected using a methylthiazolyl-tetrazolium bromide assay and the results demonstrated that knockdown of β-catenin significantly inhibited the proliferation of U251 cells in a time- and dose-dependent manner (P<0.01). Cell apoptosis rate was analyzed using flow cytometry and Annexin V-fluorescein isothiocyanate/propidium iodide staining demonstrated that β-catenin siRNA significantly increased the apoptosis of U251 cells (P<0.01). Furthermore, the results of an in vitro scratch assay demonstrated that β-catenin silencing suppressed the proliferation of U251 cells, as compared with the control group (P<0.01). In vivo, β-catenin expression levels in U251 cells were significantly inhibited (P<0.01) following β-catenin short hairpin (sh)RNA lentiviral-vector transfection, as detected by western blot analysis and RT-qPCR. Tumorigenicity experiments demonstrated that β-catenin inhibition significantly increased the survival rate of nude mice. The results of the present study demonstrated that knockdown of β-catenin expression significantly inhibited the progression of human glioma cancer cells, in vitro and in vivo; thus suggesting that β-catenin silencing may be a novel therapy for the treatment of human glioma. PMID:26998037

  19. TIPE2 Inhibits Hypoxia-Induced Wnt/β-Catenin Pathway Activation and EMT in Glioma Cells.

    PubMed

    Liu, Zhi-Jun; Liu, Hong-Lin; Zhou, Hai-Cun; Wang, Gui-Cong

    2016-01-01

    Hypoxia-induced epithelial-to-mesenchymal transition (EMT) could facilitate tumor progression. TIPE2, the tumor necrosis factor-α (TNF-α)-induced protein 8-like 2 (also known as TNFAIP8L2), is a member of the TNF-α-induced protein 8 (TNFAIP8, TIPE) family and has been involved in the development and progression of several tumors. However, the effects of TIPE2 on the EMT process in glioma cells and the underlying mechanisms of these effects have not been previously reported. In our study, we assessed the roles of TIPE2 in the EMT process in glioma cells in response to hypoxia. Our results indicated that TIPE2 expression was significantly decreased in human glioma cell lines. TIPE2 overexpression significantly inhibited hypoxia-induced migration and invasion, as well as suppressed the EMT process in glioma cells. Furthermore, TIPE2 overexpression prevented hypoxia-induced expression of β-catenin, cyclin D1, and c-myc in human glioma cells. In summary, these data suggest that TIPE2 overexpression inhibited hypoxia-induced Wnt/β-catenin pathway activation and EMT in glioma cells.

  20. Double strand break repair by homologous recombination is regulated by cell cycle-independent signaling via ATM in human glioma cells.

    PubMed

    Golding, Sarah E; Rosenberg, Elizabeth; Khalil, Ashraf; McEwen, Alison; Holmes, Matthew; Neill, Steven; Povirk, Lawrence F; Valerie, Kristoffer

    2004-04-09

    To investigate double strand break (DSB) repair and signaling in human glioma cells, we stably transfected human U87 (ATM(+), p53(+)) glioma cells with a plasmid having a single I-SceI site within an inactive green fluorescent protein (GFP) expression cassette, allowing for the detection of homologous recombination repair (HRR) by GFP expression. HRR and nonhomologous end joining (NHEJ) were also determined by PCR. DSB repair was first detected at 12 h postinfection with an adenovirus expressing I-SceI with repair reaching plateau levels between 24 and 48 h. Within this time frame, NHEJ predominated over HRR in the range of 3-50-fold. To assess the involvement of ATM in DSB repair, we first examined whether ATM was associated with the DSB. Chromatin immunoprecipitation showed that ATM was present at the site of the DSB as early as 18 h postinfection. In cells treated with caffeine, an inhibitor of ATM, HRR was reduced, whereas NHEJ was not. In support of this finding, GFP flow cytometry demonstrated that caffeine reduced HRR by 90% under conditions when ATM kinase activity was inhibited. Dominant-negative ATM expressed from adenovirus inhibited HRR by 45%, also having little to no effect on NHEJ. Furthermore, HRR was inhibited by caffeine in serum-starved cells arrested in G(0)/G(1), suggesting that ATM is also important for HRR outside of the S and G(2) cell cycle phases. Altogether, these results demonstrate that HRR contributes substantially to DSB repair in human glioma cells, and, importantly, ATM plays a critical role in regulating HRR but not NHEJ throughout the cell cycle.

  1. Resveratrol induces cellular senescence with attenuated mono-ubiquitination of histone H2B in glioma cells

    SciTech Connect

    Gao, Zhen; Xu, Michael S.; Barnett, Tamara L.; Xu, C. Wilson

    2011-04-08

    Research highlights: {yields} Resveratrol induces cellular senescence in glioma cell. {yields} Resveratrol inhibits mono-ubiquitination of histone H2B at K120. {yields} Depletion of RNF20, phenocopies the inhibitory effects of resveratrol. {yields} Mono-ubiquitination of histone H2B at K120 is a novel target of resveratrol. {yields} RNF20 inhibits cellular senescence in proliferating glioma cells. -- Abstract: Resveratrol (3,4',5-trihydroxy-trans-stilbene), a polyphenol naturally occurring in grapes and other plants, has cancer chemo-preventive effects and therapeutic potential. Although resveratrol modulates multiple pathways in tumor cells, how resveratrol or its affected pathways converge on chromatin to mediate its effects is not known. Using glioma cells as a model, we showed here that resveratrol inhibited cell proliferation and induced cellular hypertrophy by transforming spindle-shaped cells to enlarged, irregular and flatten-shaped ones. We further showed that resveratrol-induced hypertrophic cells expressed senescence-associated-{beta}-galactosidase, suggesting that resveratrol-induced cellular senescence in glioma cells. Consistent with these observations, we demonstrated that resveratrol inhibited clonogenic efficiencies in vitro and tumor growth in a xenograft model. Furthermore, we found that acute treatment of resveratrol inhibited mono-ubiquitination of histone H2B at K120 (uH2B) in breast, prostate, pancreatic, lung, brain tumor cells as well as primary human cells. Chronic treatment with low doses of resveratrol also inhibited uH2B in the resveratrol-induced senescent glioma cells. Moreover, we showed that depletion of RNF20, a ubiquitin ligase of histone H2B, inhibited uH2B and induced cellular senescence in glioma cells in vitro, thereby recapitulated the effects of resveratrol. Taken together, our results suggest that uH2B is a novel direct or indirect chromatin target of resveratrol and RNF20 plays an important role in inhibiting cellular

  2. Endothelial Progenitor Cells (EPCs) as Gene Carrier System for Rat Model of Human Glioma

    PubMed Central

    Varma, Nadimpalli Ravi S.; Janic, Branislava; Iskander, A. S. M.; Shankar, Adarsh; Bhuiyan, Mohammed P. I.; Soltanian-Zadeh, Hamid; Jiang, Quan; Barton, Kenneth; Ali, Meser M.; Arbab, Ali S.

    2012-01-01

    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 glioma therapy as

  3. Lipidomic analysis reveals a radiosensitizing role of gamma-linolenic acid in glioma cells.

    PubMed

    Antal, Otilia; Péter, Mária; Hackler, László; Mán, Imola; Szebeni, Gábor; Ayaydin, Ferhan; Hideghéty, Katalin; Vigh, László; Kitajka, Klára; Balogh, Gábor; Puskás, Laszló G

    2015-09-01

    Previous studies have demonstrated that gamma-linolenic acid (GLA) is effective against glioma cells under both in vitro and in vivo conditions. In the present study we determined how GLA alone or in combination with irradiation alters the fatty acid (FA) and lipid profiles, the lipid droplet (LD) content, the lipid biosynthetic gene expression and the apoptosis of glioma cells. In GLA-treated cells direct correlations were found between the levels of various FAs and the expression of the corresponding FA biosynthetic genes. The total levels of saturated and monosaturated FAs decreased in concert with the down-regulation of FASN and SCD1 gene expression. Similarly, decreased FADS1 gene expression was paralleled by lowered arachidonic acid (20:4 n-6) and eicosapentaenoic acid (20:5 n-3) contents, while the down-regulation of FADS2 expression was accompanied by a diminished docosahexaenoic acid (22:6 n-3) content. Detailed mass spectrometric analyses revealed that individual treatments gave rise to distinct lipidomic fingerprints. Following uptake, GLA was subjected to elongation, resulting in dihomo-gamma-linolenic acid (20:3 n-6, DGLA), which was used for the synthesis of the LD constituent triacylglycerols and cholesteryl esters. Accordingly, an increased number of LDs were observed in response to GLA administration after irradiation. GLA increased the radioresponsiveness of U87 MG cells, as demonstrated by an increase in the number of apoptotic cells determined by FACS analysis. In conclusion, treatment with GLA increased the apoptosis of irradiated glioma cells, and GLA might therefore increase the therapeutic efficacy of irradiation in the treatment of gliomas.

  4. Heparin affin regulatory peptide/pleiotrophin negatively affects diverse biological activities in C6 glioma cells.

    PubMed

    Parthymou, Anastasia; Lampropoulou, Evgenia; Mikelis, Constantinos; Drosou, Georgia; Papadimitriou, Evangelia

    2008-01-01

    Heparin affin regulatory peptide (HARP) or pleiotrophin seems to be involved in the progression of several tumors of diverse origin. In this study, we tried to determine the role of HARP in rat C6 glioma cells by using an antisense strategy for inhibition of HARP expression. Decrease of the expression of endogenous HARP in C6 cells (AS-C6 cells) significantly increased proliferation, migration, and anchorage-independent growth of cells. Implantation of AS-C6 cells onto chicken embryo chorioallantoic membranes resulted in a significant increase of tumor-induced angiogenesis compared with that induced by non-transfected or C6 cells transfected with the plasmid alone (PC-C6 cells). In the same line, conditioned medium from AS-C6 cells significantly increased endothelial cell proliferation, migration, and tube formation in vitro compared with the effect of conditioned medium from C6 or PC-C6 cells. Interestingly, vascular endothelial growth factor (VEGF) induced C6 cell proliferation and migration, and SU1496, a selective inhibitor of VEGF receptor 2 (VEGFR2), blocked increased glioma cell growth, migration, and angiogenicity observed in AS-C6 cell cultures. The above results seem to be due to a direct interaction between HARP and VEGF in the culture medium of C6 and PC-C6 cells, while AS-C6 cells secreted comparable amounts of VEGF that do not interact with HARP. Collectively, these data suggest that HARP negatively affects diverse biological activities in C6 glioma cells, mainly due to binding of HARP to VEGF, which may sequester secreted VEGF from signalling through VEGFR2.

  5. Golgi Phosphoprotein 3 Inhibits the Apoptosis of Human Glioma Cells in Part by Downregulating N-myc Downstream Regulated Gene 1

    PubMed Central

    Li, Xin; Li, Mengyou; Tian, Xiuli; Li, QingZhe; Lu, Qingyang; Yan, Jinqiang; Jia, Qingbin; Zhang, Lianqun; Li, Xueyuan; Li, Xingang

    2016-01-01

    Background Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human cancers. Our previous study showed that GOLPH3 expression in glioma tissues was related to the severity of the malignancy of the cancer. However, the mechanism by which GOLPH3 affects cell apoptosis is largely unknown. The present study was designed to explore the possible mechanism of GOLPH3 in cell apoptosis. Material/Methods To analyze the biological role of GOLPH3 in glioma cells, we used GOLPH3 small interference RNA in apoptosis of glioma cells. The apoptosis of glioma cells was detected by flow cytometry. The expression level of GOLPH3 and NDRG1 protein was determined by Western blot analyses and immunohistochemical staining, respectively, to evaluate their association with glioma. Tumor tissues were collected from patients with glioma. Normal cerebral tissues were acquired from cerebral trauma patients undergoing internal decompression surgery. Results We confirm that the decrease of GOLPH3 that promotes the apoptosis of glioma cells may be regulated by the activation of NDRG1 and cleaved capcase 3. There was a inverse association between GOLPH3 and NDRG1 in glioma samples. Conclusions Our findings indicate that GOLPH3 and NDRG1 both play an important role in glioma etiology. Either GOLPH3 or NDRG1 might be a potential candidate for malignant glioma therapy. PMID:27698340

  6. Restoration of Sensitivity in Chemo — Resistant Glioma Cells by Cold Atmospheric Plasma

    PubMed Central

    Köritzer, Julia; Boxhammer, Veronika; Schäfer, Andrea; Shimizu, Tetsuji; Klämpfl, Tobias G.; Li, Yang-Fang; Welz, Christian; Schwenk-Zieger, Sabina; Morfill, Gregor E.; Zimmermann, Julia L.; Schlegel, Jürgen

    2013-01-01

    Glioblastoma (GBM) is the most common and aggressive brain tumor in adults. Despite multimodal treatments including surgery, chemotherapy and radiotherapy the prognosis remains poor and relapse occurs regularly. The alkylating agent temozolomide (TMZ) has been shown to improve the overall survival in patients with malignant gliomas, especially in tumors with methylated promoter of the O6-methylguanine-DNA-methyltransferase (MGMT) gene. However, intrinsic and acquired resistance towards TMZ makes it crucial to find new therapeutic strategies aimed at improving the prognosis of patients suffering from malignant gliomas. Cold atmospheric plasma is a new auspicious candidate in cancer treatment. In the present study we demonstrate the anti-cancer properties of different dosages of cold atmospheric plasma (CAP) both in TMZ-sensitive and TMZ-resistant cells by proliferation assay, immunoblotting, cell cycle analysis, and clonogenicity assay. Importantly, CAP treatment restored the responsiveness of resistant glioma cells towards TMZ therapy. Concomitant treatment with CAP and TMZ led to inhibition of cell growth and cell cycle arrest, thus CAP might be a promising candidate for combination therapy especially for patients suffering from GBMs showing an unfavorable MGMT status and TMZ resistance. PMID:23704990

  7. Potent tumor tropism of induced pluripotent stem cells and induced pluripotent stem cell-derived neural stem cells in the mouse intracerebral glioma model.

    PubMed

    Yamazoe, Tomohiro; Koizumi, Shinichiro; Yamasaki, Tomohiro; Amano, Shinji; Tokuyama, Tsutomu; Namba, Hiroki

    2015-01-01

    Although neural and mesenchymal stem cells have been well-known to have a strong glioma tropism, this activity in induced pluripotent stem cells (iPSCs) has not yet been fully studied. In the present study, we tested tumor tropic activity of mouse iPSCs and neural stem cells derived from the iPSC (iPS-NSCs) using in vitro Matrigel invasion chamber assay and in vivo mouse intracranial tumor model. Both iPSC and iPS-NSC had a similar potent in vitro tropism for glioma conditioned media. The migrated iPSCs to the gliomas kept expressing Nanog-GFP gene, suggesting no neuronal or glial differentiation. iPSCs or iPS-NSCs labeled with 5-bromo-2-deoxyuridine were intracranially implanted in the contralateral hemisphere to the GL261 glioma cell implantation in the allogeneic C57BL/6 mouse. Active migration of both stem cells was observed 7 days after implantation. Again, the iPSCs located in the tumor area expressed Nanog-GFP gene, suggesting that the migrated cells were still iPSCs. These findings demonstrated that both iPSCs and iPS-NSCs had potent glioma tropism and could be candidates as vehicles in stem cell-based glioma therapy.

  8. Concomitant treatment of F98 glioma cells with new liposomal platinum compounds and ionizing radiation.

    PubMed

    Charest, Gabriel; Paquette, Benoit; Fortin, David; Mathieu, David; Sanche, Léon

    2010-04-01

    Despite significant advances, the radiotherapy and chemotherapy protocols marginally improve the overall survival of patients with glioblastoma. Lipoplatin(TM), and Lipoxal(TM), the liposomal formulations of cisplatin and oxaliplatin respectively, were tested on the F98 glioma cells for their ability to improve the cell uptake and increase the synergic effect when combined with ionizing radiation. The cytotoxicity and synergic effect of platinum compounds were assessed by colony formation assay, while the cellular uptake was measured by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). After 4 h exposure with platinum compounds, cells were irradiated (1.5-6.6 Gy) with a (60)Co source. The liposomal formulations were compared to their liposome-free analogs and to carboplatin. The concomitant treatment of F98 cells with carboplatin and radiation produced the highest radiosensitizing effect (30-fold increase). Among the platinum compounds tested, Lipoplatin(TM) produced the most promising results. This liposomal formulation of cisplatin improved the cell uptake by 3-fold, and its radiosensitizing potential was enhanced by 14-fold. Although Lipoxal(TM) can potentially reduce the adverse effect of oxaliplatin, a synergic effect with radiation was measured only when incubated at a concentration higher than its IC50. Conversely, concomitant treatment with cisplatin did not result in a synergic effect, as in fact a radioprotective effect was measured on the F98 cells. In conclusion, among the five platinum compounds tested, carboplatin and Lipoplatin(TM) showed the best radiosensitizing effect. Lipoplatin(TM) seems the most promising since it led to the best cellular incorporation and has already been reported to be less neurotoxic than other platinum compounds.

  9. High affinity receptors for vasoactive intestinal peptide on a human glioma cell line

    SciTech Connect

    Nielsen, F.C.; Gammeltoft, S.; Westermark, B.; Fahrenkrug, J. )

    1990-11-01

    Vasoactive intestinal peptide (VIP) bound with high affinity (Kd 0.13 nmol/l) to receptors on the human glioma cell line U-343 MG Cl 2:6. The receptors bound the related peptides helodermin, PHM and secretin with 10, 400 and 5000 times lower affinity, respectively. Deamidated VIP (VIP-COOH) and (des-His1)VIP bound with 10 and 100 times lower affinity. The fragment VIP(7-28) displaced 25% of the receptor-bound {sup 125}I-VIP whereas VIP(16-28) and VIP(1-22-NH2) were inactive. The binding of {sup 125}I-VIP could be completely inhibited by 10 mumol/l of the antagonists (N-Ac-Tyr1,D-Phe2)GRF(1-29)-NH2, (pCl-D-Phe6,Leu17)VIP and VIP(10-28); in contrast, the antagonist L-8-K was inactive. Affinity labeling showed that VIP bound to proteins with Mr's of 75 kDa, 66 kDa and 50 kDa, respectively. Following binding, the peptide was rapidly internalized, and at steady-state only 20% of cell-associated {sup 125}I-VIP was bound to receptors on the cell surface. The internalized {sup 125}I-VIP was completely degraded to {sup 125}I-tyrosine which was released from the cells. Degradation of internalized {sup 125}I-VIP was significantly reduced by chloroquine phenanthroline and pepstatin-A. Surface binding and internalization of {sup 125}I-VIP was increased 3 times by phenanthroline, and pepstatin-A caused a 5 times increase in surface binding. Chloroquine reduced surface-bound {sup 125}I-VIP, but caused retention of internalized {sup 125}I-VIP.

  10. Precursor N-cadherin mediates glial cell line-derived neurotrophic factor-promoted human malignant glioma.

    PubMed

    Xiong, Ye; Liu, Liyun; Zhu, Shuang; Zhang, Baole; Qin, Yuxia; Yao, Ruiqin; Zhou, Hao; Gao, Dian Shuai

    2017-02-12

    As the most prevalent primary brain tumor, gliomas are highly metastatic, invasive and are characteristic of high levels of glial cell-line derived neurotrophic factor (GDNF). GDNF is an important factor for invasive glioma cell growth; however, the underlying mechanism involved is unclear. In this study, we affirm a significantly higher expression of the precursor of N-cadherin (proN-cadherin) in most gliomas compared with normal brain tissues. Our findings reveal that GDNF interacts with the extracellular domain of proN-cadherin, which suggests that proN-cadherin mediates GDNF-induced glioma cell migration and invasion. We hypothesize that proN-cadherin might cause homotypic adhesion loss within neighboring cells and at the same time promote heterotypic adhesion within the extracellular matrix (ECM) through a certain mechanism. This study also demonstrates that the interaction between GDNF and proN-cadherin activates specific intracellular signaling pathways; furthermore, GDNF promoted the secretion of matrix metalloproteinase-9 (MMP-9), which degrades the ECM via proN-cadherin. To reach the future goal of developing novel therapies of glioma, this study, reveals a unique mechanism of glioma cell migration and invasion.

  11. Bufalin induces the interplay between apoptosis and autophagy in glioma cells through endoplasmic reticulum stress.

    PubMed

    Shen, Shuying; Zhang, Yi; Wang, Zhen; Liu, Rui; Gong, Xingguo

    2014-01-01

    Malignant gliomas are common primary tumors of the central nervous system. The prognosis of patients with malignant glioma is poor in spite of current intensive therapy and thus novel therapeutic modalities are necessary. Bufalin is the major component of Chan-Su (a traditional Chinese medicine) extracts from the venom of Bufo gargarizan. In this study, we evaluated the growth inhibitory effect of bufalin on glioma cells and explored the underlying molecular mechanisms. Our results showed that bufalin inhibited the growth of glioma cells significantly. Mechanistic studies demonstrated that bufalin induced apoptosis through mitochondrial apoptotic pathway. In addition, bufalin was also found to induce ER stress-mediated apoptosis, which was supported by the up- regulation of ER stress markers, CHOP and GRP78, and augmented phosphorylation of PERK and eIF2α as well as cleavage of caspase-4. Downregulation of CHOP using siCHOP RNA attenuated bufalin-induced apoptosis, further confirming the role of ER stress response in mediating bufalin-induced apoptosis. Evidence of bufalin-induced autophagy included formation of the acidic vesicular organelles, increase of autophagolysosomes and LC3-II accumulation. Further experiments showed that the mechanism of bufalin-induced autophagy associated with ATP deleption involved an increase in the active form of AMPK, decreased phosphorylation levels of mTOR and its downstream targets 4EBP1 and p70S6K1. Furthermore, TUDC and silencing of eIF2α or CHOP partially blocked bufalin-induced accumulation of LC3-II, which indicated that ER stress preceded bufalin-induced autophagy and PERK/eIF2α/CHOP signaling pathway played a major part in the process. Blockage of autophagy increased expression of ER stress associated proteins and the ratio of apoptosis, indicating that autophagy played a cytoprotective role in bufalin induced ER stress and cell death. In conclusion, bufalin inhibits glioma cell growth and induces interplay between

  12. Malignant Transformation in Glioma Steered by an Angiogenic Switch: Defining a Role for Bone Marrow-Derived Cells

    PubMed Central

    Pisapia, David; Greenfield, Jeffrey P

    2016-01-01

    Low-grade gliomas, such as pilocytic astrocytoma and subependymoma, are often characterized as benign tumors due to their relative circumscription radiologically and typically non-aggressive biologic behavior. In contrast, low-grades that are by their nature diffusely infiltrative, such as diffuse astrocytomas and oligodendrogliomas, have the potential to transform into malignant high-grade counterparts and, given sufficient time, invariably do so. These high-grade gliomas carry very poor prognoses and are largely incurable, warranting a closer look at what causes this adverse transition. A key characteristic that distinguishes low- and high-grade gliomas is neovascularization: it is absent in low-grade gliomas, but prolific in high-grade gliomas, providing the tumor with ample blood supply for exponential growth. It has been well described in the literature that bone marrow-derived cells (BMDCs) may contribute to the angiogenic switch that is responsible for malignant transformation of low-grade gliomas. In this review, we will summarize the current literature on BMDCs and their known contribution to angiogenesis-associated tumor growth in gliomas. PMID:26973806

  13. Reirradiation of Large-Volume Recurrent Glioma With Pulsed Reduced-Dose-Rate Radiotherapy

    SciTech Connect

    Adkison, Jarrod B.; Tome, Wolfgang; Seo, Songwon; Richards, Gregory M.; Robins, H. Ian; Rassmussen, Karl; Welsh, James S.; Mahler, Peter A.; Howard, Steven P.

    2011-03-01

    Purpose: Pulsed reduced-dose-rate radiotherapy (PRDR) is a reirradiation technique that reduces the effective dose rate and increases the treatment time, allowing sublethal damage repair during irradiation. Patients and Methods: A total of 103 patients with recurrent glioma underwent reirradiation using PRDR (86 considered to have Grade 4 at PRDR). PRDR was delivered using a series of 0.2-Gy pulses at 3-min intervals, creating an apparent dose rate of 0.0667 Gy/min to a median dose of 50 Gy (range, 20-60) delivered in 1.8-2.0-Gy fractions. The mean treatment volume was 403.5 {+-} 189.4 cm{sup 3} according to T{sub 2}-weighted magnetic resonance imaging and a 2-cm margin. Results: For the initial or upgraded Grade 4 cohort (n = 86), the median interval from the first irradiation to PRDR was 14 months. Patients undergoing PRDR within 14 months of the first irradiation (n = 43) had a median survival of 21 weeks. Those treated {>=}14 months after radiotherapy had a median survival of 28 weeks (n = 43; p = 0.004 and HR = 1.82 with a 95% CI ranging from 1.25 to 3.10). These data compared favorably to historical data sets, because only 16% of the patients were treated at first relapse (with 46% treated at the second relapse, 32% at the third or fourth relapse, and 4% at the fourth or fifth relapse). The median survival since diagnosis and retreatment was 6.3 years and 11.4 months for low-grade, 4.1 years and 5.6 months for Grade 3, and 1.6 years and 5.1 months for Grade 4 tumors, respectively, according to the initial histologic findings. Multivariate analysis revealed age at the initial diagnosis, initial low-grade disease, and Karnofsky performance score of {>=}80 to be significant predictors of survival after initiation of PRDR. Conclusion: PRDR allowed for safe retreatment of larger volumes to high doses with palliative benefit.

  14. AS1411-Induced Growth Inhibition of Glioma Cells by Up-Regulation of p53 and Down-Regulation of Bcl-2 and Akt1 via Nucleolin

    PubMed Central

    Cheng, Ye; Zhao, Gang; Zhang, Siwen; Nigim, Fares; Zhou, Guangtong; Yu, Zhiyun; Song, Yang; Chen, Yong; Li, Yunqian

    2016-01-01

    AS1411 binds nucleolin (NCL) and is the first oligodeoxynucleotide aptamer to reach phase I and II clinical trials for the treatment of several cancers. However, the mechanisms by which AS1411 targets and kills glioma cells and tissues remain unclear. Here we report that AS1411 induces cell apoptosis and cycle arrest, and inhibits cell viability by up-regulation of p53 and down-regulation of Bcl-2 and Akt1 in human glioma cells. NCL was overexpressed in both nucleus and cytoplasm in human glioma U87, U251 and SHG44 cells compared to normal human astrocytes (NHA). AS1411 bound NCL and inhibited the proliferation of glioma cells but not NHA, which was accompanied with up-regulation of p53 and down-regulation of Bcl-2 and Akt1. Moreover, AS1411 treatment resulted in the G2/M cell cycle arrest in glioma cells, which was however abolished by overexpression of NCL. Further, AS1411 induced cell apoptosis, which was prevented by silencing of p53 and overexpression of Bcl-2. In addition, AS1411 inhibited the migration and invasion of glioma cells in an Akt1-dependent manner. Importantly, AS1411 inhibited the growth of glioma xenograft and prolonged the survival time of glioma tumor-bearing mice. These results revealed a promising treatment of glioma by oligodeoxynucleotide aptamer. PMID:27907160

  15. AS1411-Induced Growth Inhibition of Glioma Cells by Up-Regulation of p53 and Down-Regulation of Bcl-2 and Akt1 via Nucleolin.

    PubMed

    Cheng, Ye; Zhao, Gang; Zhang, Siwen; Nigim, Fares; Zhou, Guangtong; Yu, Zhiyun; Song, Yang; Chen, Yong; Li, Yunqian

    2016-01-01

    AS1411 binds nucleolin (NCL) and is the first oligodeoxynucleotide aptamer to reach phase I and II clinical trials for the treatment of several cancers. However, the mechanisms by which AS1411 targets and kills glioma cells and tissues remain unclear. Here we report that AS1411 induces cell apoptosis and cycle arrest, and inhibits cell viability by up-regulation of p53 and down-regulation of Bcl-2 and Akt1 in human glioma cells. NCL was overexpressed in both nucleus and cytoplasm in human glioma U87, U251 and SHG44 cells compared to normal human astrocytes (NHA). AS1411 bound NCL and inhibited the proliferation of glioma cells but not NHA, which was accompanied with up-regulation of p53 and down-regulation of Bcl-2 and Akt1. Moreover, AS1411 treatment resulted in the G2/M cell cycle arrest in glioma cells, which was however abolished by overexpression of NCL. Further, AS1411 induced cell apoptosis, which was prevented by silencing of p53 and overexpression of Bcl-2. In addition, AS1411 inhibited the migration and invasion of glioma cells in an Akt1-dependent manner. Importantly, AS1411 inhibited the growth of glioma xenograft and prolonged the survival time of glioma tumor-bearing mice. These results revealed a promising treatment of glioma by oligodeoxynucleotide aptamer.

  16. Noscapine induces apoptosis in human glioma cells by an apoptosis-inducing factor-dependent pathway.

    PubMed

    Newcomb, Elizabeth W; Lukyanov, Yevgeniy; Smirnova, Iva; Schnee, Tona; Zagzag, David

    2008-07-01

    Previously, we identified noscapine as a small molecule inhibitor of the hypoxia-inducible factor-1 pathway in hypoxic human glioma cells and human umbilical vein endothelial cells. Noscapine is a nontoxic ingredient in cough medicine currently used in clinical trials for patients with non-Hodgkin's lymphoma or chronic lymphocytic leukemia to assess antitumor efficacy. Here, we have evaluated the sensitivity of four human glioma cell lines to noscapine-induced apoptosis. Noscapine was a potent inhibitor of proliferation and inducer of apoptosis. Induction of apoptosis was associated with activation of the c-jun N-terminal kinase signaling pathway concomitant with inactivation of the extracellular signal regulated kinase signaling pathway and phosphorylation of the antiapoptotic protein Bcl-2. Noscapine-induced apoptosis was associated with the release of mitochondrial proteins apoptosis-inducing factor (AIF) and/or cytochrome c. In some glioma cell lines, only AIF release occurred without cytochrome c release or poly (ADP-ribose) polymerase cleavage. Knock-down of AIF decreased noscapine-induced apoptosis. Our results suggest the potential importance of noscapine as a novel agent for use in patients with glioblastoma owing to its low toxicity profile and its potent anticancer activity.

  17. HSPB1 Enhances SIRT2-Mediated G6PD Activation and Promotes Glioma Cell Proliferation

    PubMed Central

    Cao, Fei; Chen, Mantao; Zheng, Xiujue; Zhan, Renya

    2016-01-01

    Heat shock proteins belong to a conserved protein family and are involved in multiple cellular processes. Heat shock protein 27 (Hsp27), also known as heat HSPB1, participates in cellular responses to not only heat shock, but also oxidative or chemical stresses. However, the contribution of HSPB1 to anti-oxidative response remains unclear. Here, we show that HSPB1 activates G6PD in response to oxidative stress or DNA damage. HSPB1 enhances the binding between G6PD and SIRT2, leading to deacetylation and activation of G6PD. Besides, HSPB1 activates G6PD to sustain cellular NADPH and pentose production in glioma cells. High expression of HSPB1 correlates with poor survivalrate of glioma patients. Together, our study uncovers the molecular mechanism by which HSPB1 activates G6PD to protect cells from oxidative and DNA damage stress. PMID:27711253

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

    PubMed

    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

    2016-06-27

    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.

  19. DICER governs characteristics of glioma stem cells and the resulting tumors in xenograft mouse models of glioblastoma

    PubMed Central

    Alamsahebpour, Amir; Burrell, Kelly; Li, Mira; Karabork, Merve; Ekinci, Can; Koch, Elizabeth; Solaroglu, Ihsan; Chang, Jeffery T.; Wouters, Bradly; Aldape, Kenneth; Zadeh, Gelareh

    2016-01-01

    The RNAse III endonuclease DICER is a key regulator of microRNA (miRNA) biogenesis and is frequently decreased in a variety of malignancies. We characterized the role of DICER in glioblastoma (GB), specifically demonstrating its effects on the ability of glioma stem-like cells (GSCs) to form tumors in a mouse model of GB. DICER silencing in GSCs reduced their stem cell characteristics, while tumors arising from these cells were more aggressive, larger in volume, and displayed a higher proliferation index and lineage differentiation. The resulting tumors, however, were more sensitive to radiation treatment. Our results demonstrate that DICER silencing enhances the tumorigenic potential of GSCs, providing a platform for analysis of specific relevant miRNAs and development of potentially novel therapies against GB. PMID:27421140

  20. Shift of microRNA profile upon glioma cell migration using patient-derived spheroids and serum-free conditions.

    PubMed

    Munthe, Sune; Halle, Bo; Boldt, Henning B; Christiansen, Helle; Schmidt, Steffen; Kaimal, Vivek; Xu, Jessica; Zabludoff, Sonya; Mollenhauer, Jan; Poulsen, Frantz R; Kristensen, Bjarne W

    2017-03-01

    Glioblastoma multiforme (GBM) is the most frequent malignant primary brain tumor. A major reason for the overall median survival being only 14.6 months is migrating tumor cells left behind after surgery. Another major reason is tumor cells having a so-called cancer stem cell phenotype being therefore resistant towards traditional chemo- and radiotherapy. A group of novel molecular targets are microRNAs (miRNAs). MiRNAs are small non-coding RNAs exerting post-transcriptional regulation of gene expression. The aim of this study was to identify differentially expressed miRNAs in migrating GBM cells using serum-free stem cell conditions. We used patient-derived GBM spheroid cultures for a novel serum-free migration assay. MiRNA expression of migrating tumor cells isolated at maximum migration speed was compared with corresponding spheroids using an OpenArray Real-Time PCR System. The miRNA profiling revealed 30 miRNAs to be differentially expressed. In total 13 miRNAs were upregulated and 17 downregulated in migrating cells compared to corresponding spheroids. The three most deregulated miRNAs, miR-1227 (up-regulated), miR-32 (down-regulated) and miR-222 (down-regulated), were experimentally overexpressed. A non-significantly increased migration rate was observed after miR-1227 overexpression. A significantly reduced migration rate was observed after miR-32 and miR-222 overexpression. In conclusion a shift in microRNA profile upon glioma cell migration was identified using an assay avoiding serum-induced migration. Both the miRNA profiling and the functional validation suggested that miR-1227 may be associated with increased migration and miR-32 and miR-222 with decreased migration. These miRNAs may represent potential novel targets in migrating glioma cells.

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

    PubMed

    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.

  2. A Tubulin Binding Peptide Targets Glioma Cells Disrupting Their Microtubules, Blocking Migration, and Inducing Apoptosis

    PubMed Central

    Berges, Raphael; Balzeau, Julien; Peterson, Alan C; Eyer, Joel

    2012-01-01

    Despite aggressive treatment regimes, glioma remains a largely fatal disease. Current treatment limitations are attributed to the precarious locations within the brain where such tumors grow, their highly infiltrative nature precluding complete resection and lack of specificity among agents capable of attenuating their growth. Here, we show that in vitro, glioma cells of diverse origins internalize a peptide encompassing a tubulin-binding site (TBS) on the neurofilament light protein. The internalized peptide disrupts the microtubule network, inhibits migration and proliferation, and leads to apoptosis. Using an intracerebral transplant model, we show that most, if not all, of these responses to peptide exposure also occur in vivo. Notably, a single intratumor injection significantly attenuates tumor growth, while neither peptide uptake nor downstream consequences are observed elsewhere in the host nervous system. Such preferential uptake suggests that the peptide may have potential as a primary or supplementary glioblastoma treatment modality by exploiting its autonomous microtubule-disrupting activity or engaging its capacity to selectively target glioma cells with other cell-disrupting cargos. PMID:22491214

  3. Paeoniflorin inhibits human glioma cells via STAT3 degradation by the ubiquitin–proteasome pathway

    PubMed Central

    Nie, Xiao-hu; Ou-yang, Jia; Xing, Ying; Li, Dan-yan; Dong, Xing-yu; Liu, Ru-en; Xu, Ru-xiang

    2015-01-01

    We investigated the underlying mechanism for the potent proapoptotic effect of paeoniflorin (PF) on human glioma cells in vitro, focusing on signal transducer and activator of transcription 3 (STAT3) signaling. Significant time- and dose-dependent apoptosis and inhibition of proliferation were observed in PF-treated U87 and U251 glioma cells. Expression of STAT3, its active form phosphorylated STAT3 (p-STAT3), and several downstream molecules, including HIAP, Bcl-2, cyclin D1, and Survivin, were significantly downregulated upon PF treatment. Overexpression of STAT3 induced resistance to PF, suggesting that STAT3 was a critical target of PF. Interestingly, rapid downregulation of STAT3 was consistent with its accelerated degradation, but not with its dephosphorylation or transcriptional modulation. Using specific inhibitors, we demonstrated that the prodegradation effect of PF on STAT3 was mainly through the ubiquitin–proteasome pathway rather than via lysosomal degradation. These findings indicated that PF-induced growth suppression and apoptosis in human glioma cells through the proteasome-dependent degradation of STAT3. PMID:26508835

  4. In vitro anti-tubulin effects of mebendazole and fenbendazole on canine glioma cells.

    PubMed

    Lai, S R; Castello, S A; Robinson, A C; Koehler, J W

    2017-01-12

    Benzimidazole anthelmintics have reported anti-neoplastic effects both in vitro and in vivo. The purpose of this study was to evaluate the in vitro chemosensitivity of three canine glioma cell lines to mebendazole and fenbendazole. The mean inhibitory concentration (IC50 ) (±SD) obtained from performing the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay after treating J3T, G06-A, and SDT-3G cells for 72 h with mebendazole were 0.030 ± 0.003, 0.080 ± 0.015 and 0.030 ± 0.006 μM respectively, while those for fenbendazole were 0.550  ± 0.015, 1.530 ± 0.159 and 0.690 ± 0.095 μM; treatment of primary canine fibroblasts for 72 h at IC50 showed no significant effect. Immunofluorescence studies showed disruption of tubulin after treatment. Mebendazole and fenbendazole are cytotoxic in canine glioma cell lines in vitro and may be good candidates for treatment of canine gliomas. Further in vivo studies are required.

  5. The neuro-steroid, 3beta androstene 17alpha diol exhibits potent cytotoxic effects on human malignant glioma and lymphoma cells through different programmed cell death pathways.

    PubMed

    Graf, M R; Jia, W; Loria, R M

    2007-09-03

    The neuro-steroids 3beta-androstene-17alpha-diol (17alpha-AED), 3beta-androstene-17beta-diol (17beta-AED), 3beta-androstene-7alpha,-17beta-triol (7alpha-AET) and 3beta-androstene-7beta,-17beta-triol (7beta-AET) are metabolites of dehydroepiandrosterone and are produced in neuro-ectodermal tissue. Both epimers of androstenediols (17alpha-AED and 17beta-AED) and androstenetriols (7alpha-AET and 7beta-AET) have markedly different biological functions of their chemical analogue. We investigated the cytotoxic activity of these neuro-steroids on human T98G and U251MG glioblastoma and U937 lymphoma cells. Proliferation studies showed that 17alpha-AED is the most potent inhibitor, with an IC(50) approximately 15 microM. For T98G glioma, 90% inhibition was achieved with 25 muM of 17alpha-AED. Other neuro-steroids tested only marginally suppressed cell proliferation. Reduced cell adherence and viability could be detected after 18 h of 17alpha-AED exposure. Treatment with 17alpha-AED induced a significant level of apoptosis in U937 lymphoma cells, but not in the glioma cells. Cytopathology of 17alpha-AED-treated T98G cells revealed the presence of multiple cytoplasmic vacuoles. Acridine orange staining demonstrated the formation of acidic vesicular organelles in 17alpha-AED-treated T98G and U251MG, which was inhibited by bafilomycin A1. These findings indicate that 17alpha-AED bears the most potent cytotoxic activity of the neuro-steroids tested, and the effectiveness may depend on the number of hydroxyls and their position on the androstene molecule. These cytotoxic effects may utilize a non-apoptotic pathway in malignant glioma cells.

  6. miR-92a-3p Exerts Various Effects in Glioma and Glioma Stem-Like Cells Specifically Targeting CDH1/β-Catenin and Notch-1/Akt Signaling Pathways

    PubMed Central

    Song, Hang; Zhang, Yao; Liu, Na; Zhao, Sheng; Kong, Yan; Yuan, Liudi

    2016-01-01

    MicroRNAs (miRNAs) are implicated in the regulation of tumor progression and stemness of cancer stem-like cells. Recently, miR-92a-3p was reported to be up-regulated in human glioma samples. Nevertheless, the precise role of miR-92a-3p in glioma cells and glioma stem-like cells (GSCs) has not been fully elucidated. It is necessary to clarify the function of miR-92a-3p in glioma and GSCs to develop novel therapeutic approaches for glioma patients. In the present study, we applied methyl-thiazolyl-tetrazolium (MTT) assay and Transwell assay to measure the proliferation rate and metastatic potential of glioma cells. Meanwhile, the self-renewal ability of GSCs was detected by tumor sphere formation assay. The results revealed that down-regulation of miR-92a-3p suppressed the glioma cell malignancy in vitro. Moreover, knockdown of miR-92a-3p led to a reduction of tumorgenesis in vivo. Interestingly, we also observed that up-regulation of miR-92a-3p could inhibit the stemness of GSCs. Subsequent mechanistic investigation indicated that cadherin 1 (CDH1)/β-catenin signaling and Notch-1/Akt signaling were the downstream pathways of miR-92a-3p in glioma cells and GSCs, respectively. These results suggest that miR-92a-3p plays different roles in glioma cells and GSCs through regulating different signaling pathways. PMID:27801803

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

    PubMed

    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.

  8. High expression of adenylate cyclase-associated protein 1 accelerates the proliferation, migration and invasion of neural glioma cells.

    PubMed

    Bao, Zhen; Qiu, Xiaojun; Wang, Donglin; Ban, Na; Fan, Shaochen; Chen, Wenjuan; Sun, Jie; Xing, Weikang; Wang, Yunfeng; Cui, Gang

    2016-04-01

    Adenylate cyclase-associated protein 1 (CAP1), a conserved member of cyclase-associated proteins was reported to be associated with the proliferation, migration or invasion of the tumors of pancreas, breast and liver, and was involved in astrocyte proliferation after acute Traumatic Brain Injury (TBI). In this study, we sought to investigate the character of CAP1 in the pathological process of human glioma by detecting human glioma specimens and cell lines. 43 of 100 specimens showed high expression of CAP1 via immunohistochemistry. With statistics analysis, we found out the expression level of CAP1 was correlated with the WHO grades of human glioma and was great positively related to Ki-67 (p<0.01). In vitro, silencing CAP1 in U251 and U87MG, the glioma cell lines with the relatively higher expression of CAP1, induced the proliferation of the cells significantly retarded, migration and invasion as well. Obviously, our results indicated that CAP1 participated in the molecular pathological process of glioma indeed, and in a certain sense, CAP1 might be a potential and promising molecular target for glioma diagnosis and therapies in the future.

  9. Endogenous GABAA receptor activity suppresses glioma growth.

    PubMed

    Blanchart, A; Fernando, R; Häring, M; Assaife-Lopes, N; Romanov, R A; Andäng, M; Harkany, T; Ernfors, P

    2017-02-09

    Although genome alterations driving glioma by fueling cell malignancy have largely been resolved, less is known of the impact of tumor environment on disease progression. Here, we demonstrate functional GABAA receptor-activated currents in human glioblastoma cells and show the existence of a continuous GABA signaling within the tumor cell mass that significantly affects tumor growth and survival expectancy in mouse models. Endogenous GABA released by tumor cells, attenuates proliferation of the glioma cells with enriched expression of stem/progenitor markers and with competence to seed growth of new tumors. Our results suggest that GABA levels rapidly increase in tumors impeding further growth. Thus, shunting chloride ions by a maintained local GABAA receptor activity within glioma cells has a significant impact on tumor development by attenuating proliferation, reducing tumor growth and prolonging survival, a mechanism that may have important impact on therapy resistance and recurrence following tumor resection.

  10. Splicing factors PTBP1 and PTBP2 promote proliferation and migration of glioma cell lines

    PubMed Central

    Cheung, Hannah C.; Hai, Tao; Zhu, Wen; Baggerly, Keith A.; Tsavachidis, Spiridon; Krahe, Ralf

    2009-01-01

    Polypyrimidine tract-binding protein 1 (PTBP1) is a multi-functional RNA-binding protein that is aberrantly overexpressed in glioma. PTBP1 and its brain-specific homologue polypyrimidine tract-binding protein 2 (PTBP2) regulate neural precursor cell differentiation. However, the overlapping and non-overlapping target transcripts involved in this process are still unclear. To determine why PTBP1 and not PTBP2 would promote glial cell-derived tumours, both PTBP1 and PTBP2 were knocked down in the human glioma cell lines U251 and LN229 to determine the role of these proteins in cell proliferation, migration, and adhesion. Surprisingly, removal of both PTBP1 and PTBP2 slowed cell proliferation, with the double knockdown having no additive effects. Decreased expression of both proteins individually and in combination inhibited cell migration and increased adhesion of cells to fibronectin and vitronectin. A global survey of differential exon expression was performed following PTBP1 knockdown in U251 cells using the Affymetrix Exon Array to identify PTBP1-specific splicing targets that enhance gliomagenesis. In the PTBP1 knockdown, previously determined targets were unaltered in their splicing patterns. A single gene, RTN4 (Nogo) had significantly enhanced inclusion of exon 3 when PTBP1 was removed. Overexpression of the splice isoform containing exon 3 decreased cell proliferation to a similar degree as the removal of PTBP1. These results provide the first evidence that RNA-binding proteins affect the invasive and rapid growth characteristics of glioma cell lines. Its actions on proliferation appear to be mediated, in part, through alternative splicing of RTN4. PMID:19506066

  11. HOXB1 Is a Tumor Suppressor Gene Regulated by miR-3175 in Glioma

    PubMed Central

    Han, Liang; Liu, Dehua; Li, Zhaohui; Tian, Nan; Han, Ziwu; Wang, Guang; Fu, Yao; Guo, Zhigang; Zhu, Zifeng

    2015-01-01

    The HOXB1 gene plays a critical role as an oncogene in diverse tumors. However, the functional role of HOXB1 and the mechanism regulating HOXB1 expression in glioma are not fully understood. A preliminary bioinformatics analysis showed that HOXB1 is ectopically expressed in glioma, and that HOXB1 is a possible target of miR-3175. In this study, we investigated the function of HOXB1 and the relationship between HOXB1 and miR-3175 in glioma. We show that HOXB1 expression is significantly downregulated in glioma tissues and cell lines, and that its expression may be closely associated with the degree of malignancy. Reduced HOXB1 expression promoted the proliferation and invasion of glioma cells, and inhibited their apoptosis in vitro, and the downregulation of HOXB1 was also associated with worse survival in glioma patients. More importantly, HOXB1 was shown experimentally to be a direct target of miR-3175 in this study. The downregulated expression of miR-3175 inhibited cell proliferation and invasion, and promoted apoptosis in glioma. The oncogenicity induced by low HOXB1 expression was prevented by an miR-3175 inhibitor in glioma cells. Our results suggest that HOXB1 functions as a tumor suppressor, regulated by miR-3175 in glioma. These results clarify the pathogenesis of glioma and offer a potential target for its treatment. PMID:26565624

  12. A novel recombinant protein of ephrinA1-PE38/GM-CSF activate dendritic cells vaccine in rats with glioma.

    PubMed

    Li, Ming; Wang, Bin; Wu, Zhonghua; Zhang, Jiadong; Shi, Xiwen; Cheng, Wenlan; Han, Shuangyin

    2015-07-01

    Dendritic cells loaded with tumor-associated antigens can effectively stimulate the antitumor immune response of cytotoxic T lymphocytes in the body, which facilitates the development of novel and effective treatments for cancer. In this study, the adenovirus-mediated ephrinA1-PE38/GM-CSF was successfully constructed using the overlap extension method, and verified with sequencing analysis. HEK293 cells were infected with the adenovirus and the cellular expression of ephrinA1-PE38/GM-CSF was measured with an enzyme-linked immunosorbent assay. The recombinant adenovirus was then delivered into the tumor-bearing rats and the results showed that such treatment significantly reduced the volumes of gliomas and improved the survival of the transplanted rats. The results from immunohistochemistry and flow cytometry suggested that this immunomodulatory agent cause activation of dendritic cells. The findings that ephrinA1-PE38/GM-CSF had a high efficacy in the activation of the dendritic cells would facilitate the development of in vivo dendritic-cell vaccines for the treatment of gliomas in rats. Our new method of DC vaccine production induces not only a specific local antitumor immune response but also a systemic immunotherapeutic effect. In addition, this method completely circumvents the risk of contamination related to the in vitro culture of DCs, thus greatly improving the safety and feasibility of clinical application of the DC vaccines in glioma.

  13. Systematic Identification of Single Amino Acid Variants in Glioma Stem-Cell-Derived Chromosome 19 Proteins

    PubMed Central

    2015-01-01

    Novel proteoforms with single amino acid variations represent proteins that often have altered biological functions but are less explored in the human proteome. We have developed an approach, searching high quality shotgun proteomic data against an extended protein database, to identify expressed mutant proteoforms in glioma stem cell (GSC) lines. The systematic search of MS/MS spectra using PEAKS 7.0 as the search engine has recognized 17 chromosome 19 proteins in GSCs with altered amino acid sequences. The results were further verified by manual spectral examination, validating 19 proteoforms. One of the novel findings, a mutant form of branched-chain aminotransferase 2 (p.Thr186Arg), was verified at the transcript level and by targeted proteomics in several glioma stem cell lines. The structure of this proteoform was examined by molecular modeling in order to estimate conformational changes due to mutation that might lead to functional modifications potentially linked to glioma. Based on our initial findings, we believe that our approach presented could contribute to construct a more complete map of the human functional proteome. PMID:25399873

  14. The prosurvival role of autophagy in Resveratrol-induced cytotoxicity in human U251 glioma cells

    PubMed Central

    2009-01-01

    Background Previous study reported that resveratrol has anti-tumor activity. In this study, we investigated the involvement of autophagy in the resveratrol-induced apoptotic death of human U251 glioma cells. Methods The growth inhibition of U251 cells induced by resveratrol was assessed with methyl thiazolyl tetrazolium (MTT). The activation of autophagy and proapoptotic effect were characterized by monodansylcadaverine labeling and Hoechst stain, respectively. Mitochondrialtransmembrane potential (ΔΨm) was measured as a function of drug treatment using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1). The role of autophagy and apoptosis in the resveratrol-induced death of U251 cells was assessed using autophagic and caspase inhibitors. Immunofluorescence, flow cytometry, and Western blot analysis were used to study the apoptotic and autophagic mechanisms. Results Methyl thiazolyl tetrazolium (MTT) assays indicated that resveratrol decreased the viability of U251 cells in a dose- and time-dependent manner. Flow cytometry analysis indicated that resveratrol increased cell population at sub-G1 phase, an index of apoptosis. Furthermore, resveratrol-induced cell death was associated with a collapse of the mitochondrial membrane potential. The pan-caspase inhibitor Z-VAD-fmk suppressed resveratrol-induced U251 cell death. Resveratrol stimulated autophagy was evidenced by punctuate monodansylcadaverine(MDC) staining and microtubule-associated protein light chain 3 (LC3) immunoreactivty. Resveratrol also increased protein levels of beclin 1 and membrane form LC3 (LC3-II). Autophagy inhibitors 3-methylademine (3-MA) and bafilomycin A1 sensitized the cytotoxicity of resveratrol. Conclusion Together, these findings indicate that resveratrol induces autophagy in human U251 glioma cells and autophagy suppressed resveratrol-induced apoptosis. This study thus suggests that autophagy inhibitors can increase the cytotoxicity of resveratrol to

  15. CD133 Expression Is Not Synonymous to Immunoreactivity for AC133 and Fluctuates throughout the Cell Cycle in Glioma Stem-Like Cells.

    PubMed

    Barrantes-Freer, Alonso; Renovanz, Mirjam; Eich, Marcus; Braukmann, Alina; Sprang, Bettina; Spirin, Pavel; Pardo, Luis A; Giese, Alf; Kim, Ella L

    2015-01-01

    A transmembrane protein CD133 has been implicated as a marker of stem-like glioma cells and predictor for therapeutic response in malignant brain tumours. CD133 expression is commonly evaluated by using antibodies specific for the AC133 epitope located in one of the extracellular domains of membrane-bound CD133. There is conflicting evidence regarding the significance of the AC133 epitope as a marker for identifying stem-like glioma cells and predicting the degree of malignancy in glioma cells. The reasons for discrepant results between different studies addressing the role of CD133/AC133 in gliomas are unclear. A possible source for controversies about CD133/AC133 is the widespread assumption that expression patterns of the AC133 epitope reflect linearly those of the CD133 protein. Consequently, the readouts from AC133 assessments are often interpreted in terms of the CD133 protein. The purpose of this study is to determine whether and to what extent do the readouts obtained with anti-AC133 antibody correspond to the level of CD133 protein expressed in stem-like glioma cells. Our study reveals for the first time that CD133 expressed on the surface of glioma cells is poorly immunoreactive for AC133. Furthermore, we provide evidence that the level of CD133 occupancy on the surface of glioma cells fluctuates during the cell cycle. Our results offer a new explanation for numerous inconsistencies regarding the biological and clinical significance of CD133/AC133 in human gliomas and call for caution in interpreting the lack or presence of AC133 epitope in glioma cells.

  16. Protooncogene bcl-2 gene transfer abrogates Fas/APO-1 antibody-mediated apoptosis of human malignant glioma cells and confers resistance to chemotherapeutic drugs and therapeutic irradiation.

    PubMed Central

    Weller, M; Malipiero, U; Aguzzi, A; Reed, J C; Fontana, A

    1995-01-01

    The majority of human malignant glioma cells express Fas/APO-1 and are susceptible to Fas/APO-1 antibody-mediated apoptosis in vitro. The sensitivity of Fas/APO-1-positive glioma cell lines to Fas/APO-1 antibody-mediated killing correlates inversely with the constitutive expression of the antiapoptotic protooncogene bcl-2. Here we report that BCL-2 protein expression of human glial tumors in vivo correlates with malignant transformation in that BCL-2 immunoreactive glioma cells were more abundant in WHO grade III/IV gliomas than in grade I/II gliomas. Fas/APO-1 antibody-sensitive human glioma cell lines stably transfected with a murine bcl-2 cDNA acquired resistance to Fas/APO-1 antibody-mediated apoptosis. Forced expression of bcl-2 also attenuated TNF alpha-mediated cytotoxicity of glioma cell lines in the presence of actinomycin D and cycloheximide and conferred partial protection from irradiation and the cancer chemotherapy drugs, cisplatin and BCNU. Preexposure of the glioma cell lines to the cytokines, IFN gamma and TNF alpha, which sensitize for Fas/APO-1-dependent killing, partially overcame bcl-2-mediated rescue from apoptosis, suggesting that multimodality immunotherapy involving cytokines and Fas/APO-1 targeting might eventually provide a promising approach to the treatment of human malignant gliomas. Images PMID:7539458

  17. Ibuprofen and Diclofenac Restrict Migration and Proliferation of Human Glioma Cells by Distinct Molecular Mechanisms

    PubMed Central

    Leidgens, Verena; Seliger, Corinna; Jachnik, Birgit; Welz, Tobias; Leukel, Petra; Vollmann-Zwerenz, Arabel; Bogdahn, Ulrich; Kreutz, Marina; Grauer, Oliver M.; Hau, Peter

    2015-01-01

    Background Non-steroidal anti-inflammatory drugs (NSAIDs) have been associated with anti-tumorigenic effects in different tumor entities. For glioma, research has generally focused on diclofenac; however data on other NSAIDs, such as ibuprofen, is limited. Therefore, we performed a comprehensive investigation of the cellular, molecular, and metabolic effects of ibuprofen and diclofenac on human glioblastoma cells. Methods Glioma cell lines were treated with ibuprofen or diclofenac to investigate functional effects on proliferation and cell motility. Cell cycle, extracellular lactate levels, lactate dehydrogenase-A (LDH-A) expression and activity, as well as inhibition of the Signal Transducer and Activator of Transcription 3 (STAT-3) signaling pathway, were determined. Specific effects of diclofenac and ibuprofen on STAT-3 were investigated by comparing their effects with those of the specific STAT-3 inhibitor STATTIC. Results Ibuprofen treatment led to a stronger inhibition of cell growth and migration than treatment with diclofenac. Proliferation was affected by cell cycle arrest at different checkpoints by both agents. In addition, diclofenac, but not ibuprofen, decreased lactate levels in all concentrations used. Both decreased STAT-3 phosphorylation; however, diclofenac led to decreased c-myc expression and subsequent reduction in LDH-A activity, whereas treatment with ibuprofen in higher doses induced c-myc expression and less LDH-A alteration. Conclusions This study indicates that both ibuprofen and diclofenac strongly inhibit glioma cells, but the subsequent metabolic responses of both agents are distinct. We postulate that ibuprofen may inhibit tumor cells also by COX- and lactate-independent mechanisms after long-term treatment in physiological dosages, whereas diclofenac mainly acts by inhibition of STAT-3 signaling and downstream modulation of glycolysis. PMID:26485029

  18. Laminin isoforms and their integrin receptors in glioma cell migration and invasiveness: Evidence for a role of alpha5-laminin(s) and alpha3beta1 integrin.

    PubMed

    Kawataki, Tomoyuki; Yamane, Tetsu; Naganuma, Hirofumi; Rousselle, Patricia; Andurén, Ingegerd; Tryggvason, Karl; Patarroyo, Manuel

    2007-11-01

    Glioma cell infiltration of brain tissue often occurs along the basement membrane (BM) of blood vessels. In the present study we have investigated the role of laminins, major structural components of BMs and strong promoters of cell migration. Immunohistochemical studies of glioma tumor tissue demonstrated expression of alpha2-, alpha3-, alpha4- and alpha5-, but not alpha1-, laminins by the tumor vasculature. In functional assays, alpha3 (Lm-332/laminin-5)- and alpha5 (Lm-511/laminin-10)-laminins strongly promoted migration of all glioma cell lines tested. alpha1-Laminin (Lm-111/laminin-1) displayed lower activity, whereas alpha2 (Lm-211/laminin-2)- and alpha4 (Lm-411/laminin-8)-laminins were practically inactive. Global integrin phenotyping identified alpha3beta1 as the most abundant integrin in all the glioma cell lines, and this laminin-binding integrin exclusively or largely mediate the cell migration. Moreover, pretreatment of U251 glioma cells with blocking antibodies to alpha3beta1 integrin followed by intracerebral injection into nude mice inhibited invasion of the tumor cells into the brain tissue. The cell lines secreted Lm-211, Lm-411 and Lm-511, at different ratios. The results indicate that glioma cells secrete alpha2-, alpha4- and alpha5-laminins and that alpha3- and alpha5-laminins, found in brain vasculature, selectively promote glioma cell migration. They identify alpha3beta1 as the predominant integrin and laminin receptor in glioma cells, and as a brain invasion-mediating integrin.

  19. Girdin regulates the migration and invasion of glioma cells via the PI3K-Akt signaling pathway

    PubMed Central

    NI, WEIMIN; FANG, YAN; TONG, LEI; TONG, ZHAOXUE; YI, FUXIN; QIU, JIANWU; WANG, RUI; TONG, XIAOJIE

    2015-01-01

    Girdin, an actin-binding protein, is associated with cell migration and is expressed at high levels in glioma cells. However, the association between girdin and the development of glioma remains to be elucidated. In the present study, short-hairpin RNA technology was used to silence the gene expression of girdin. The effects of girdin silencing on glioma cell proliferation, migration and invasion were then assessed using a cell viability assay, wound-healing assay, transwell invasion assay, reverse transcription-quantitative polymerase chain reaction, western blot analysis and gelatin zymography. The results suggested that girdin silencing inhibited the proliferation, migration and invasion of glioma cells. In addition, the expression levels and activity of matrix metalloproteinase (MMP)-2 and MMP-9 were also affected by girdin silencing. Further mechanistic investigation indicated that girdin may regulate glioma cell migration and invasion through the phosphatidylinositol-3-kinase/protein kinase B (PI3K-Akt) signaling pathway. Therefore, the results of the present study provide a theoretical foundation for the development of anticancer drugs. PMID:26151295

  20. Suppression of wingless-type MMTV integration site family, member 1 expression by small interfering RNA inhibits U251 glioma cell growth in vitro

    PubMed Central

    DONG, LUN; DUAN, XIAO-CHUN; HAN, CHONG-XU; ZHANG, HENGZHU; WU, YONGKANG

    2015-01-01

    A Wingless-type MMTV integration site family, member 1 (Wnt-1) RNA interference expression vector was constructed during the present study, which was used to transfect the glioma U251 cell line and investigate its effect on glioma. Two 21-base oligonucleotides complementary to the coding sequence that was flanking the loop sequence were designed to form a DNA hairpin template for the target small interfering RNA (siRNA). The siRNA templates were cloned into the siRNA expression vector, pGPU6/green fluorescent protein (GFP)/Neo and the sequence was confirmed by DNA sequencing. The pGPU6/GFP/Neo-short hairpin RNA (shRNA)-Wnt-1 vector was subsequently transfected into U251 cells, and reverse transcription polymerase chain reaction and western blot analysis were used to evaluate the Wnt-1 gene silencing effect on U251 cell growth by MTT assay and flow cytometry. The Wnt-1 protein expression was significantly reduced following transfection with the recombinant plasmid, as determined by western blot analysis of the transfected U251 cells. This transfection exhibited a significantly higher death rate, as shown by MTT. Thus, the present study demonstrated that the pGPU6/GFP/Neo-shRNA-Wnt-1 vector inhibited Wnt-1 protein expression. However, further investigations regarding the Wnt signaling pathway in glioma pathogenesis are required. PMID:25435937

  1. [THE INFLUENCE OF PROGENITOR NEURO- CELLS SUPERNATANT ON THE LYMPHO- CYTES CYTOTOXIC FUNCTION IN RATS WITH GLIOMA].

    PubMed

    Liubich, L D; Lisyany, N I

    2015-01-01

    The impact of rat neurogenic progenitor cells supernatant (RPNS) on the cytotoxic function of lymphocytes in rats under conditions of physiological norm and experimentally modeled tumor (brain glioma strain 101.8) was studied. The research was carried out in animals with inoculated tumor without RPNS injection and with different regimes of RPNS injection (thrice repeated from 5th to 10th day after glioma inoculation as well as 1 week and 1 month before tumor inoculation). Comparison groups included rats without glioma who triple injected with RPNS; and intact animals (control). RPNS was received from suspension of neurogenic progenitor cells (NPC) of rat brain on 14th day of gestation and injected intraperitoneally (0,12 mg per animal). Cytotoxic function of lymphocytes of experimental rats was evaluated in MTT-colorimetric test with allogeneic glioma cells. RPNS administration increased the cytotoxic activity of lymphocytes in vitro tests with allogeneic tumor cells in intact animals (to 37-38%) as well as in rats with glioma (to 11-22%). Under the RPNS influence the life expectancy and median survival of tumor-bearing animals increased (an average of 3-4 days). RPNS input modes such as triple injection from 5th to 10th day after glioma inoculation and 1 week before inoculation were the most effective. Thus, indirect tumor-inhibiting effect under intraperitoneal. RPNS administration in rats with glioma is demonstrated, which is obviously due to increased efficiency of cytotoxic function of immune cells of animals with inoculated tumor under the influence of the factors produced by NPC.

  2. Effect of saw palmetto extract on PI3K cell signaling transduction in human glioma.

    PubMed

    Yang, Yang; Hui, Lv; Yuqin, Che; Jie, Li; Shuai, Hou; Tiezhu, Zhou; Wei, Wang

    2014-08-01

    Saw palmetto extract can induce the apoptosis of prostate cancer cells. The aim of the present study was to investigate the effect of saw palmetto extract on the phosphatidylinositol 3-kinase (PI3K)/Akt signaling transduction pathway in human glioma U87 and U251 cell lines. Suspensions of U87 and U251 cells in a logarithmic growth phase were seeded into six-well plates at a density of 10(4) cells/well. In the experimental group, 1 μl/ml saw palmetto extract was added, while the control group was cultured without a drug for 24 h. The expression levels of PI3K, B-cell lymphoma-extra large (Bcl-xL) and p53 were evaluated through western blot analysis. In the experimental group, the U87 and U251 cells exhibited a lower expression level of PI3K protein as compared with the control group (t=6.849; P<0.001). In addition, the two cell lines had a higher expression level of p53 protein in the experimental group as compared with the control group (t=40.810; P<0.001). Protein expression levels of Bcl-xL decreased significantly in the experimental group as compared with the control group (t=19.640; P=0.000). Therefore, saw palmetto extract induces glioma cell growth arrest and apoptosis via decreasing PI3K/Akt signal transduction.

  3. Effect of saw palmetto extract on PI3K cell signaling transduction in human glioma

    PubMed Central

    YANG, YANG; HUI, LV; YUQIN, CHE; JIE, LI; SHUAI, HOU; TIEZHU, ZHOU; WEI, WANG

    2014-01-01

    Saw palmetto extract can induce the apoptosis of prostate cancer cells. The aim of the present study was to investigate the effect of saw palmetto extract on the phosphatidylinositol 3-kinase (PI3K)/Akt signaling transduction pathway in human glioma U87 and U251 cell lines. Suspensions of U87 and U251 cells in a logarithmic growth phase were seeded into six-well plates at a density of 104 cells/well. In the experimental group, 1 μl/ml saw palmetto extract was added, while the control group was cultured without a drug for 24 h. The expression levels of PI3K, B-cell lymphoma-extra large (Bcl-xL) and p53 were evaluated through western blot analysis. In the experimental group, the U87 and U251 cells exhibited a lower expression level of PI3K protein as compared with the control group (t=6.849; P<0.001). In addition, the two cell lines had a higher expression level of p53 protein in the experimental group as compared with the control group (t=40.810; P<0.001). Protein expression levels of Bcl-xL decreased significantly in the experimental group as compared with the control group (t=19.640; P=0.000). Therefore, saw palmetto extract induces glioma cell growth arrest and apoptosis via decreasing PI3K/Akt signal transduction. PMID:25009620

  4. PD-1 marks dysfunctional regulatory T cells in malignant gliomas

    PubMed Central

    Lowther, Daniel E.; Goods, Brittany A.; Lucca, Liliana E.; Lerner, Benjamin A.; Raddassi, Khadir; van Dijk, David; Hernandez, Amanda L.; Duan, Xiangguo; Gunel, Murat; Coric, Vlad; Krishnaswamy, Smita; Hafler, David A.

    2016-01-01

    Immunotherapies targeting the immune checkpoint receptor programmed cell death protein 1 (PD-1) have shown remarkable efficacy in treating cancer. CD4+CD25hiFoxP3+ Tregs are critical regulators of immune responses in autoimmunity and malignancies, but the functional status of human Tregs expressing PD-1 remains unclear. We examined functional and molecular features of PD-1hi Tregs in healthy subjects and patients with glioblastoma multiforme (GBM), combining functional assays, RNA sequencing, and cytometry by time of flight (CyTOF). In both patients with GBM and healthy subjects, circulating PD-1hi Tregs displayed reduced suppression of CD4+ effector T cells, production of IFN-γ, and molecular signatures of exhaustion. Transcriptional profiling of tumor-resident Tregs revealed that several genes coexpressed with PD-1 and associated with IFN-γ production and exhaustion as well as enrichment in exhaustion signatures compared with circulating PD-1hi Tregs. CyTOF analysis of circulating and tumor-infiltrating Tregs from patients with GBM treated with PD-1-blocking antibodies revealed that treatment shifts the profile of circulating Tregs toward a more exhausted phenotype reminiscent of that of tumor-infiltrating Tregs, further increasing IFN-γ production. Thus, high PD-1 expression on human Tregs identifies dysfunctional, exhausted Tregs secreting IFN-γ that exist in healthy individuals and are enriched in tumor infiltrates, possibly losing function as they attempt to modulate the antitumoral immune responses. PMID:27182555

  5. MiR-15b Targets Cyclin D1 to Regulate Proliferation and Apoptosis in Glioma Cells

    PubMed Central

    Sun, Guan; Shi, Lei; Yan, Shushan; Wan, Zhengqiang; Jiang, Nan; Fu, Linshan; Li, Min; Guo, Jun

    2014-01-01

    Aim. To investigate the role and mechanism of miR-15b in the proliferation and apoptosis of glioma. Methods. The miR-15b mimics were transfected into human glioma cells to upregulate the miR-15b expression. Cyclin D1 was determined by both western blotting analysis and luciferase reporter assay. Methylthiazol tetrazolium (MTT) and flow cytometry were employed to detect the cell proliferation, cell cycle, and apoptosis. Results. Overexpression of miR-15b inhibits proliferation by arrested cell cycle progression and induces apoptosis, possibly by directly targeting Cyclin D1. Both luciferase assay and bioinformatics search revealed a putative target site of miR-15b binding to the 3′-UTR of Cyclin D1. Moreover, expression of miR-15b in glioma tissues was found to be inversely correlated with Cyclin D1 expression. Enforced Cyclin D1 could abrogate the miR-15b-mediated cell cycle arrest and apoptosis. Conclusions. Our findings identified that miR-15b may function as a glioma suppressor by targeting the Cyclin D1, which may provide a novel therapeutic strategy for treatment of glioma. PMID:24995320

  6. CacyBP/SIP inhibits Doxourbicin-induced apoptosis of glioma cells due to activation of ERK1/2.

    PubMed

    Tang, Yuan; Zhan, Wenjian; Cao, Tong; Tang, Tianjin; Gao, Yong; Qiu, Zhichao; Fu, Chunling; Qian, Fengyuan; Yu, Rutong; Shi, Hengliang

    2016-03-01

    Calcyclin-binding protein or Siah-1-interacting protein (CacyBP/SIP) was previously reported to promote the proliferation of glioma cells. However, the effect of CacyBP/SIP on apoptosis of glioma is poorly understood. Here, our study shows that CacyBP/SIP plays a role in inhibiting doxorubicin (DOX) induced apoptosis of glioma cells U251 and U87. Overexpression of CacyBP/SIP obviously suppressed the DOX-induced cell apoptosis. On the contrary, silencing of CacyBP/SIP significantly promoted it. Further investigation indicated that inhibition of apoptosis by CacyBP/SIP was relevant to its nuclear translocation in response to the DOX treatment. Importantly, we found that the level of p-ERK1/2 in nuclei was related to the nuclear accumulation of CacyBP/SIP. Finally, the role of CacyBP/SIP was confirmed in vivo in a mouse model with the cell line stably silencing CacyBP/SIP. Taken together, our results suggest that CacyBP/SIP plays an important role in inhibiting apoptosis of glioma cells which might be mediated by ERK1/2 signaling pathway, which will provide some guidance for the treatment of glioma.

  7. Silencing erythropoietin receptor on glioma cells reinforces efficacy of temozolomide and X-rays through senescence and mitotic catastrophe

    PubMed Central

    Pérès, Elodie A.; Gérault, Aurélie N.; Valable, Samuel; Roussel, Simon; Toutain, Jérôme; Divoux, Didier; Guillamo, Jean-Sébastien; Sanson, Marc; Bernaudin, Myriam; Petit, Edwige

    2015-01-01

    Hypoxia-inducible genes may contribute to therapy resistance in glioblastoma (GBM), the most aggressive and hypoxic brain tumours. It has been recently reported that erythropoietin (EPO) and its receptor (EPOR) are involved in glioma growth. We now investigated whether EPOR signalling may modulate the efficacy of the GBM current treatment based on chemotherapy (temozolomide, TMZ) and radiotherapy (X-rays). Using RNA interference, we showed on glioma cell lines (U87 and U251) that EPOR silencing induces a G2/M cell cycle arrest, consistent with the slowdown of glioma growth induced by EPOR knock-down. In vivo, we also reported that EPOR silencing combined with TMZ treatment is more efficient to delay tumour recurrence and to prolong animal survival compared to TMZ alone. In vitro, we showed that EPOR silencing not only increases the sensitivity of glioma cells to TMZ as well as X-rays but also counteracts the hypoxia-induced chemo- and radioresistance. Silencing EPOR on glioma cells exposed to conventional treatments enhances senescence and induces a robust genomic instability that leads to caspase-dependent mitotic death by increasing the number of polyploid cells and cyclin B1 expression. Overall these data suggest that EPOR could be an attractive target to overcome therapeutic resistance toward ionising radiation or temozolomide. PMID:25544764

  8. Compression Stiffening of Brain and its Effect on Mechanosensing by Glioma Cells

    NASA Astrophysics Data System (ADS)

    Pogoda, Katarzyna

    The stiffness of tissues, often characterized by their time-dependent elastic properties, is tightly controlled under normal condition and central nervous system tissue is among the softest tissues. Changes in tissue and organ stiffness occur in some physiological conditions and are frequently symptoms of diseases such as fibrosis, cardiovascular disease and many forms of cancer. Primary cells isolated from various tissues often respond to changes in the mechanical properties of their substrates, and the range of stiffness over which these responses occur appear to be limited to the tissue elastic modulus from which they are derived. Our goal was to test the hypotheses that the stiffness of tumors derived from CNS tissue differs from that of normal brain, and that transformed cells derived from such tumors exhibit mechanical responses that differ from those of normal glial cells. Unlike breast and some other cancers where the stroma and the tumor itself is substantially stiffer than the surrounding normal tissue, our data suggest that gliomas can arise without a gross change in the macroscopic tissue stiffness when measured at low strains without compression. However, both normal brain and glioma samples stiffen with compression, but not in elongation and increased shear strains. On the other hand, different classes of immortalized cells derived from human glioblastoma show substantially different responses to the stiffness of substrates in vitrowhen grown on soft polyacrylamide and hyaluronic acid gels. This outcome supports the hypothesis that compression stiffening, which might occur with increased vascularization and interstitial pressure gradients that are characteristic of tumors, effectively stiffens the environment of glioma cells, and that in situ, the elastic resistance these cells sense might be sufficient to trigger the same responses that are activated in vitro by increased substrate stiffness.

  9. Selective induction of apoptosis in glioma tumour cells by a Gynostemma pentaphyllum extract.

    PubMed

    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.

  10. Inhibition of RNA transportation induces glioma cell apoptosis via downregulation of RanGAP1 expression.

    PubMed

    Lin, Tsung-Yao; Lee, Chin-Cheng; Chen, Ku-Chung; Lin, Chien-Ju; Shih, Chwen-Ming

    2015-05-05

    The prognosis of glioblastoma remains poor, even treatment with surgery, radiation, or chemotherapy. Therefore, it is still important to develop a new strategy for treatment of glioblastoma. Previous reports demonstrated that rRNA is produced at abnormally high levels in tumor cells. Nuclear export of all non-coding RNAs are known to depend on RanGTPase system. Hydrolyzation of RanGTP-RNA complex by RanGTPase activating protein 1 (RanGAP1) releases RNA from nucleus to cytoplasm. Therefore, inhibition of RNA transportation would be a useful strategy to affect cancer cell fate. In this study, 5-30 μM of oridonin, a natural diterpenoid compound isolated from the traditional Chinese medicine, Rabdosia rubescens, induced U87MG glioma cell apoptosis and RNA accumulation in nucleus at 12h-time point. Before U87MG cell apoptosis, the RanGAP1 protein amount decreased and RanGTP accumulated in nucleus as respectively determined by immunoprecipitation and immunofluorescence, suggesting that decrease of RanGAP1 may result in nuclear entrapment of RanGTP and RNA, and then induce U87MG cell death. In contrast, over-expression of the RanGAP1 protein reversed oridonin-induced U87MG cell apoptosis. Hence, we demonstrated that downregulation of the RanGAP1 protein level by oridonin may result in RNA accumulation in nucleus via nuclear entrapment of RanGTP which eventually led to the apoptosis of glioma cells.

  11. Pioglitazone Effect on Glioma Stem Cell Lines: Really a Promising Drug Therapy for Glioblastoma?

    PubMed Central

    Butta, Valentina

    2016-01-01

    Glioblastoma multiforme (GBM) represents one of the most frequent malignant brain tumors. Current therapies do not provide real solutions to this pathology. Their failure can be ascribed to a cell subpopulation with stem-like properties called glioma stem cells (GSCs). Therefore, new therapeutic strategies GSC-targeted are needed. PPARγ, a nuclear receptor involved in lipid metabolism, has already been indicated as a promising target for antineoplastic therapies. Recent studies have reported that synthetic PPARγ agonists, already in clinical use for the treatment of type II diabetes, exhibit antineoplastic effects in a wide range of malignant tumor cells, including glioma cells. We investigated the effect of the synthetic PPARγ agonist Pioglitazone on viability, proliferation, morphology, and differentiation in six GSC lines isolated from GBM patients. We also analyzed Pioglitazone-induced changes in transcriptional levels of Wnt/β catenin related genes. Results showed that response to Pioglitazone was heterogeneous inducing an evident decrease of cell viability and proliferation only in a subset of GSC lines. We did not find any sign of cell differentiation neither observing cell morphology nor analyzing the expression of stemness and differentiation markers. Moreover, Wnt/β signaling pathway was only mildly affected from a transcriptional point of view after Pioglitazone exposure. PMID:27313600

  12. ROS-mediated cytotoxic effect of copper(II) hydrazone complexes against human glioma cells.

    PubMed

    Recio Despaigne, Angel A; Da Silva, Jeferson G; da Costa, Pryscila R; Dos Santos, Raquel G; Beraldo, Heloisa

    2014-10-27

    2-Acetylpyridine acetylhydrazone (H2AcMe), 2-benzoylpyridine acetylhydrazone (H2BzMe) and complexes [Cu(H2AcMe)Cl2] (1) and [Cu(H2BzMe)Cl2] (2) were assayed for their cytotoxicity against wild type p53 U87 and mutant p53 T98 glioma cells, and against MRC-5 fibroblast cells. Compounds 1 and 2 proved to be more active than the corresponding hydrazones against U87, but not against T98 cells. Compound 1 induced higher levels of ROS than H2AcMe in both glioma cell lines. H2AcMe and 1 induced lower levels of ROS in MRC5 than in U87 cells. Compound 2 induced lower levels of ROS in MRC5 than in T98 cells. The cytotoxic effect of 1 in U87 cells could be related to its ability to provoke the release of ROS, suggesting that the cytotoxicity of 1 might be somehow p53 dependent.

  13. Decoupling genetics, lineages, and microenvironment in IDH-mutant gliomas by single-cell RNA-seq.

    PubMed

    Venteicher, Andrew S; Tirosh, Itay; Hebert, Christine; Yizhak, Keren; Neftel, Cyril; Filbin, Mariella G; Hovestadt, Volker; Escalante, Leah E; Shaw, McKenzie L; Rodman, Christopher; Gillespie, Shawn M; Dionne, Danielle; Luo, Christina C; Ravichandran, Hiranmayi; Mylvaganam, Ravindra; Mount, Christopher; Onozato, Maristela L; Nahed, Brian V; Wakimoto, Hiroaki; Curry, William T; Iafrate, A John; Rivera, Miguel N; Frosch, Matthew P; Golub, Todd R; Brastianos, Priscilla K; Getz, Gad; Patel, Anoop P; Monje, Michelle; Cahill, Daniel P; Rozenblatt-Rosen, Orit; Louis, David N; Bernstein, Bradley E; Regev, Aviv; Suvà, Mario L

    2017-03-31

    Tumor subclasses differ according to the genotypes and phenotypes of malignant cells as well as the composition of the tumor microenvironment (TME). We dissected these influences in isocitrate dehydrogenase (IDH)-mutant gliomas by combining 14,226 single-cell RNA sequencing (RNA-seq) profiles from 16 patient samples with bulk RNA-seq profiles from 165 patient samples. Differences in bulk profiles between IDH-mutant astrocytoma and oligodendroglioma can be primarily explained by distinct TME and signature genetic events, whereas both tumor types share similar developmental hierarchies and lineages of glial differentiation. As tumor grade increases, we find enhanced proliferation of malignant cells, larger pools of undifferentiated glioma cells, and an increase in macrophage over microglia expression programs in TME. Our work provides a unifying model for IDH-mutant gliomas and a general framework for dissecting the differences among human tumor subclasses.

  14. Identification of Small Molecule Inhibitors of Human Cytochrome c Oxidase That Target Chemoresistant Glioma Cells.

    PubMed

    Oliva, Claudia R; Markert, Tahireh; Ross, Larry J; White, E Lucile; Rasmussen, Lynn; Zhang, Wei; Everts, Maaike; Moellering, Douglas R; Bailey, Shannon M; Suto, Mark J; Griguer, Corinne E

    2016-11-11

    The enzyme cytochrome c oxidase (CcO) or complex IV (EC 1.9.3.1) is a large transmembrane protein complex that serves as the last enzyme in the respiratory electron transport chain of eukaryotic mitochondria. CcO promotes the switch from glycolytic to oxidative phosphorylation (OXPHOS) metabolism and has been associated with increased self-renewal characteristics in gliomas. Increased CcO activity in tumors has been associated with tumor progression after chemotherapy failure, and patients with primary glioblastoma multiforme and high tumor CcO activity have worse clinical outcomes than those with low tumor CcO activity. Therefore, CcO is an attractive target for cancer therapy. We report here the characterization of a CcO inhibitor (ADDA 5) that was identified using a high throughput screening paradigm. ADDA 5 demonstrated specificity for CcO, with no inhibition of other mitochondrial complexes or other relevant enzymes, and biochemical characterization showed that this compound is a non-competitive inhibitor of cytochrome c When tested in cellular assays, ADDA 5 dose-dependently inhibited the proliferation of chemosensitive and chemoresistant glioma cells but did not display toxicity against non-cancer cells. Furthermore, treatment with ADDA 5 led to significant inhibition of tumor growth in flank xenograft mouse models. Importantly, ADDA 5 inhibited CcO activity and blocked cell proliferation and neurosphere formation in cultures of glioma stem cells, the cells implicated in tumor recurrence and resistance to therapy in patients with glioblastoma. In summary, we have identified ADDA 5 as a lead CcO inhibitor for further optimization as a novel approach for the treatment of glioblastoma and related cancers.

  15. Specific chemotaxis of magnetically labeled mesenchymal stem cells: Implications for MRI of glioma

    PubMed Central

    Bennewitz, Margaret F.; Tang, Kevin S.; Markakis, Eleni A.; Shapiro, Erik M.

    2012-01-01

    Purpose Glioblastoma multiforme (GBM) is a lethal disease, marked by infiltration of cancerous cells into the surrounding normal brain. The dire outcome of GBM patients stems in part from the limitations of current neuroimaging methods. Notably, early cancer detection methodologies are lacking, without the ability to identify aggressive, metastatic tumor cells. We propose a novel approach for tumor detection using MRI, based on imaging specific tumor tropism of mesenchymal stem cells (MSCs) labeled with micron-sized iron oxide particles (MPIOs). Procedures MPIO labeled and unlabeled MSCs were compared for viability, multi-lineage differentiation, and migration, where both chemotactic and chemokinetic movement were assessed in the presence of serum free medium, serum containing medium, and glioma conditioned medium. MRI was performed on agarose samples, consisting of MPIO labeled single MSCs, to confirm the capability to detect single cells. Results We determined that MPIO labeled MSCs exhibit specific and significant chemotactic migration towards glioma conditioned medium in vitro. Confocal fluorescence microscopy confirmed that MPIOs are internalized and do not impact important cell processes of MSCs. Lastly, MPIO labeled MSCs appear as single distinct, dark spots on T2* weighted MRI, supporting the robustness of this contrast agent for cell tracking. Conclusions This is the first study to show that MPIO labeled MSCs exhibit specific tropism toward tumor-secreted factors in vitro. The potential for detecting single MPIO labeled MSCs provides rationale for in vivo extension of this methodology to visualize GBM in animal models. PMID:22418788

  16. SHMT2 drives glioma cell survival in the tumor microenvironment but imposes a dependence on glycine clearance

    PubMed Central

    Kim, Dohoon; Fiske, Brian P.; Birsoy, Kivanc; Freinkman, Elizaveta; Kami, Kenjiro; Possemato, Richard; Chudnovsky, Yakov; Pacold, Michael E.; Chen, Walter W.; Cantor, Jason R.; Shelton, Laura M.; Gui, Dan Y.; Kwon, Manjae; Ramkissoon, Shakti H.; Ligon, Keith L.; Kang, Seong Woo; Snuderl, Matija; Heiden, Matthew G. Vander; Sabatini, David M.

    2015-01-01

    SUMMARY Cancer cells adapt their metabolic processes to support rapid proliferation, but less is known about how cancer cells alter metabolism to promote cell survival in a poorly vascularized tumor microenvironment1–3. Here, we identify a key role for serine and glycine metabolism in the survival of brain cancer cells within the ischemic zones of gliomas. In human glioblastoma multiforme (GBM), mitochondrial serine hydroxymethyltransferase (SHMT2) and glycine decarboxylase (GLDC) are highly expressed in the pseudopalisading cells that surround necrotic foci. We find that SHMT2 activity limits that of pyruvate kinase (PKM2) and reduces oxygen consumption, eliciting a metabolic state that confers a profound survival advantage to cells in poorly vascularized tumor regions. GLDC inhibition impairs cells with high SHMT2 levels as the excess glycine not metabolized by GLDC can be converted to the toxic molecules aminoacetone and methylglyoxal. Thus, SHMT2 is required for cancer cells to adapt to the tumor environment, but also renders these cells sensitive to glycine cleavage system inhibition. PMID:25855294

  17. Chloroquine-induced autophagic vacuole accumulation and cell death in glioma cells is p53 independent

    PubMed Central

    Geng, Ying; Kohli, Latika; Klocke, Barbara J.; Roth, Kevin A.

    2010-01-01

    Glioblastoma (GBM) is a high-grade central nervous system malignancy and despite aggressive treatment strategies, GBM patients have a median survival time of just 1 year. Chloroquine (CQ), an antimalarial lysosomotropic agent, has been identified as a potential adjuvant in the treatment regimen of GBMs. However, the mechanism of CQ-induced tumor cell death is poorly defined. We and others have shown that CQ-mediated cell death may be p53-dependent and at least in part due to the intrinsic apoptotic death pathway. Here, we investigated the effects of CQ on 5 established human GBM lines, differing in their p53 gene status. CQ was found to induce a concentration-dependent death in each of these cell lines. Although CQ treatment increased caspase-3–like enzymatic activity in all 5 cell lines, a broad-spectrum caspase inhibitor did not significantly attenuate death. Moreover, CQ caused an accumulation of autophagic vacuoles in all cell lines and was found to affect the levels and subcellular distribution of cathepsin D, suggesting that altered lysosomal function may also play a role in CQ-induced cell death. Thus, CQ can induce p53-independent death in gliomas that do not require caspase-mediated apoptosis. To potentially identify more potent chemotherapeutics, various CQ derivatives and lysosomotropic compounds were tested on the GBM cells. Quinacrine and mefloquine were found to be more potent than CQ in killing GBM cells in vitro and given their superior blood–brain barrier penetration compared with CQ may prove more efficacious as chemotherapeutic agents for GBM patients. PMID:20406898

  18. Nicotinic acid inhibits glioma invasion by facilitating Snail1 degradation

    PubMed Central

    Li, Jiejing; Qu, Jiagui; Shi, Yu; Perfetto, Mark; Ping, Zhuxian; Christian, Laura; Niu, Hua; Mei, Shuting; Zhang, Qin; Yang, Xiangcai; Wei, Shuo

    2017-01-01

    Malignant glioma is a formidable disease that commonly leads to death, mainly due to the invasion of tumor cells into neighboring tissues. Therefore, inhibition of tumor cell invasion may provide an effective therapy for malignant glioma. Here we report that nicotinic acid (NA), an essential vitamin, inhibits glioma cell invasion in vitro and in vivo. Treatment of the U251 glioma cells with NA in vitro results in reduced invasion, which is accompanied by a loss of mesenchymal phenotype and an increase in cell-cell adhesion. At the molecular level, transcription of the adherens junction protein E-cadherin is upregulated, leading to accumulation of E-cadherin protein at the cell-cell boundary. This can be attributed to NA’s ability to facilitate the ubiquitination and degradation of Snail1, a transcription factor that represses E-cadherin expression. Similarly, NA transiently inhibits neural crest migration in Xenopus embryos in a Snail1-dependent manner, indicating that the mechanism of action for NA in cell migration is evolutionarily conserved. We further show that NA injection blocks the infiltration of tumor cells into the adjacent brain tissues and improves animal survival in a rat model of glioma. These results suggest that NA treatment may be developed into a potential therapy for malignant glioma. PMID:28256591

  19. Anti-Fas/APO-1 antibody-mediated apoptosis of cultured human glioma cells. Induction and modulation of sensitivity by cytokines.

    PubMed Central

    Weller, M; Frei, K; Groscurth, P; Krammer, P H; Yonekawa, Y; Fontana, A

    1994-01-01

    Fas/APO-1 is a transmembrane protein of the nerve growth factor/TNF alpha receptor family which signals apoptotic cell death in susceptible target cells. We have investigated the susceptibility of seven human malignant glioma cell lines to Fas/APO-1-dependent apoptosis. Sensitivity to Fas/APO-1 antibody-mediated cell killing correlated with cell surface expression of Fas/APO-1. Expression of Fas/APO-1 as well as Fas/APO-1-dependent cytotoxicity were augmented by preexposure of human malignant glioma cells to IFN gamma and TNF alpha. Further, pretreatment with TGF beta 2, IL1 and IL8 enhanced Fas/APO-1 antibody-induced glioma cell apoptosis whereas other cytokines including TNF beta, IL6, macrophage colony-stimulating factor, IL10 and IL13 had no such effect. None of the human malignant glioma cell lines was susceptible to TNF alpha-induced cytotoxicity. Fas/APO-1 antibody-sensitive glioma cell lines (n = 5), but not Fas/APO-1 antibody-resistant glioma cell lines (n = 2), became sensitive to TNF alpha when co-treated with inhibitors of RNA and protein synthesis. Resistance of human glioma cells to Fas/APO-1 antibody-mediated apoptosis was mainly related to low level expression of Fas/APO-1 and appeared not to be linked to overexpression of the anti-apoptotic protooncogene, bcl-2. Given the resistance of human malignant glioma to surgery, irradiation, chemotherapy and immunotherapy, we propose that Fas/APO-1 may be a promising target for a novel locoregionary approach to human malignant glioma. This strategy gains support from the demonstration of Fas/APO-1 expression in ex vivo human malignant glioma specimens and from the absence of Fas/APO-1 in normal human brain parenchyma. Images PMID:7521890

  20. Novel small molecular inhibitors disrupt the JAK/STAT3 and FAK signaling pathways and exhibit a potent antitumor activity in glioma cells.

    PubMed

    Swiatek-Machado, Karolina; Mieczkowski, Jakub; Ellert-Miklaszewska, Aleksandra; Swierk, Piotr; Fokt, Izabela; Szymanski, Slawomir; Skora, Stanislaw; Szeja, Wiesław; Grynkiewicz, Grzegorz; Lesyng, Bogdan; Priebe, Waldemar; Kaminska, Bozena

    2012-06-01

    JAK (Janus kinase)/STAT (signal transducers and activators of transcription) signaling is involved in the regulation of cell growth, differentiation and apoptosis. Constitutive activation of STATs, in particular STAT3, is observed in a large number of human tumors, including gliomas and may contribute to oncogenesis by stimulating cell proliferation and preventing apoptosis, thus it emerges as a promising target for anti-cancer therapy. To investigate the therapeutic potential of blocking STAT3 in glioma cells a set of small synthetic molecules - caffeic acid derivatives, structurally related to AG490 was screened for its ability to inhibit STAT3. Inhibitor 2 (E)-2-cyano-N-[(S)-1-phenylethyl]-3-(pyridin-2-yl)acrylamide was the most effective in inhibition of JAK/STAT3 signaling and at doses ≥ 25 μM significantly reduced the level of phosphorylated JAK1, JAK2 and STAT3 (at Tyr705) and downregulated the expression of known STAT3 targets. In treated cells we observed rapid detachment and rounding of cells associated with reduction of focal adhesion kinase phosphorylation and activity, followed by upregulation of phosphorylated p38, JNK and ERK1/2 levels. Accumulation of cells with fragmented DNA, increases of the cleaved caspase 3 and fragmented PARP levels were detected 24 h after the treatment suggesting ongoing apoptotic cell death. Three human malignant glioblastoma cell lines defective in tumor suppressors TP53 and/or PTEN were susceptible to inhibitor 2 that induced the programmed cell death. Global gene expression profiling revealed modulation of numerous genes in cells treated with inhibitor 2 revealing novel, potential JAK/STAT targets. Our study demonstrates that suitably modified caffeic acid molecules exhibit significant cytotoxic potential toward glioma cells.

  1. Resveratrol induces apoptotic cell death in rat H4IIE hepatoma cells but necrosis in C6 glioma cells.

    PubMed

    Michels, G; Wätjen, W; Weber, N; Niering, P; Chovolou, Y; Kampkötter, A; Proksch, P; Kahl, R

    2006-08-15

    Resveratrol (trans-3,5,4',-trihydroxystilbene) is assumed to possess cancer-preventive and cancer-therapeutic properties. The aim of this project was to analyze cellular effects of resveratrol in metabolically active H4IIE rat hepatoma cells in comparison to metabolically poorly active C6 rat glioma cells. Resveratrol is rapidly taken up by both cell types and acts as a potent intracellular antioxidant. On the other hand, resveratrol in higher concentrations is relatively toxic to both cell lines as measured by the neutral red accumulation assay. In H4IIE cells, resveratrol concentrations rapidly decline to very low levels during the first hours of incubation due to formation of resveratrol glucuronides. The first resveratrol effect found at 3h after the start of resveratrol treatment was the induction of mild DNA damage as detected by the comet assay. Cell death was caused via induction of apoptosis as detected by caspase activation, oligonucleosomal DNA fragmentation and formation of apoptotic nuclei. Following DNA damage, resveratrol led to an activation of caspases 2 and 8/10 at 6h and consequently of caspase 3 at 12h, but failed to activate caspase 9. In contrast to H4IIE cells, resveratrol is not metabolised in C6 glioma cells and accumulates to concentrations which are assumed to drive the cell into necrosis. This suggests that the mode of cell death caused by resveratrol and the usefulness of resveratrol for cancer prevention and treatment critically depends on the metabolic capacity of the tumor cell to be eradicated.

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

    PubMed Central

    Massi, Paola; Valenti, Marta; Solinas, Marta; Parolaro, Daniela

    2010-01-01

    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. PMID:24281104

  3. Human umbilical cord mesenchymal stem cells inhibit C6 glioma growth via secretion of dickkopf-1 (DKK1).

    PubMed

    Ma, Shanshan; Liang, Shuo; Jiao, Hongliang; Chi, Liankai; Shi, Xinyi; Tian, Yi; Yang, Bo; Guan, Fangxia

    2014-01-01

    Mesenchymal stem cells (MSCs) represent a potential therapeutic target for glioma. We determined the molecular mechanism of inhibitory effect of human umbilical cord-derived MSCs (hUC-MSCs) on the growth of C6 glioma cells. We demonstrated that hUC-MSCs inhibited C6 cell growth and modulated the cell cycle to G0/G1 phase. The expression of β-catenin and c-Myc was downregulated in C6 cells by conditioned media from hUC-MSCs, and the levels of secreted DKK1 were positively correlated with concentrations of hUCMSCs-CM. The inhibitory effect of hUC-MSCs on C6 cell proliferation was enhanced as the concentration of DKK1 in hUCMSCs-CM increased. When DKK1 was neutralized by anti-DKK1 antibody, the inhibitory effect of hUC-MSCs on C6 cells was attenuated. Furthermore, we found that conditioned media from hUC-MSCs transfection with siRNA targeting DKK1 mRNA or pEGFPN1-DKK1 plasmid lost or enhanced the abilities to regulate the Wnt signaling in C6 cells. Therefore, hUC-MSCs inhibited C6 glioma cell growth via secreting DKK1, an inhibitor of Wnt pathway, may represent a novel therapeutic strategy for malignant glioma.

  4. Enhanced radiation-induced cytotoxic effect by 2-ME in glioma cells is mediated by induction of cell cycle arrest and DNA damage via activation of ATM pathways.

    PubMed

    Zou, Huichao; Zhao, Shiguang; Zhang, Jianhua; Lv, Gongwei; Zhang, Xu; Yu, Hongwei; Wang, Huibo; Wang, Ligang

    2007-12-14

    Glioblastoma multiform is the most common malignant primary brain tumor in adults, but there remains no effective therapeutic approach. 2-methoxyestradiol (2-ME), which is a naturally occurring metabolite of 17beta-estradiol, was shown to enhance radiotherapeutic effect in certain tumors; however, whether 2-ME can also enhance the sensitivity of glioma cells to radiotherapy remains unknown. The present study, therefore, was to address this issue using two human glioma cell lines (T98G and U251MG). These cells were irradiated with and without 2-ME and then clonogenic assay, apoptosis assay, DNA damage, and cell cycle change were examined. Results showed that 2-ME significantly enhances radiation-induced cell death in both glioma cells, shown by decreasing cell viability and increasing apoptotic cell death. No such radiosensitizing effect was observed if cells pre-treated with Estrodiol, suggesting the specifically radiosensitizing effect of 2-ME rather than a general effect of estrodials. The enhanced radio-cytotoxic effect in glioma cells by 2-ME was found to be associated with its enhancement of G(2)/M arrest and DNA damage, and phosphorylated ATM protein kinases as well as cell cycle checkpoint protein Chk2. Furthermore, inhibition of ATM by ATM inhibitor abolished 2-ME-activated Chk2 and enhanced radio-cytotoxic effects. These results suggest that 2-ME enhancement of the sensitivity of glioma cell lines to radiotherapy is mediated by induction of G2/M cell cycle arrest and increased DNA damage via activation of ATM kinases.

  5. Copper compound induces autophagy and apoptosis of glioma cells by reactive oxygen species and jnk activation

    PubMed Central

    2012-01-01

    Background Glioblastoma multiforme (GBM) is the most aggressive of the primary brain tumors, with a grim prognosis despite intensive treatment. In the past decades, progress in research has not significantly increased overall survival rate. Methods The in vitro antineoplastic effect and mechanism of action of Casiopeina III-ia (Cas III-ia), a copper compound, on rat malignant glioma C6 cells was investigated. Results Cas III-ia significantly inhibited cell proliferation, inducing autophagy and apoptosis, which correlated with the formation of autophagic vacuoles, overexpression of LC3, Beclin 1, Atg 7, Bax and Bid proteins. A decrease was detected in the mitochondrial membrane potential and in the activity of caspase 3 and 8, together with the generation of intracellular reactive oxygen species (ROS) and increased activity of c-jun NH2-terminal kinase (JNK). The presence of 3-methyladenine (as selective autophagy inhibitor) increased the antineoplastic effect of Cas III-ia, while Z-VAD-FMK only showed partial protection from the antineoplastic effect induced by Cas III-ia, and ROS antioxidants (N-acetylcysteine) decreased apoptosis, autophagy and JNK activity. Moreover, the JNK –specific inhibitor SP600125 prevented Cas III-ia-induced cell death. Conclusions Our data suggest that Cas III-ia induces cell death by autophagy and apoptosis, in part due to the activation of ROS –dependent JNK signaling. These findings support further studies of Cas III-ia as candidate for treatment of human malignant glioma. PMID:22540380

  6. hsa-mir-181a and hsa-mir-181b function as tumor suppressors in human glioma cells.

    PubMed

    Shi, Lei; Cheng, Zihao; Zhang, Junxia; Li, Rui; Zhao, Peng; Fu, Zhen; You, Yongping

    2008-10-21

    MicroRNAs (miRNAs) are small noncoding RNA molecules that regulate protein expression by cleaving or repressing the translation of target mRNAs. In mammal animals, their function mainly represses the target mRNAs transcripts via imperfectly complementary to the 3' UTR of target mRNAs. Several miRNAs have been recently reported to be involved in modulation of glioma development, especially some up-regulated miRNA, such as hsa-miR-21 and hsa-miR-221. However, here we reported that the down-regulated hsa-miR-181a and hsa-miR-181b of hsa-miR-181 family were also involved in oncogenesis of glioma. Our studies showed that hsa-miR-181a and hsa-miR-181b functioned as tumor suppressors which triggered growth inhibition, induced apoptosis and inhibited invasion in glioma cells. Furthermore, the tumor-suppressive effect of hsa-miR-181b in glioma cells was more apparent than the effect of hsa-miR-181a. These findings suggest aberrantly down-regulated hsa-miR-181a and hsa-miR-181b may be critical factors that contribute to malignant appearance in human gliomas.

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

    PubMed

    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

  8. Function of the Blood-Brain Barrier and Restriction of Drug Delivery to Invasive Glioma Cells: Findings in an Orthotopic Rat Xenograft Model of Glioma

    PubMed Central

    Agarwal, Sagar; Manchanda, Pooja; Vogelbaum, Michael A.; Ohlfest, John R.

    2013-01-01

    Despite aggressive treatment with radiation and chemotherapy, recurrence of glioblastoma multiforme (GBM) is inevitable. The objective of this study was to show that the blood-brain barrier (BBB), through a combination of tight junctions and active efflux transporters in the brain microvasculature, can significantly restrict delivery of molecularly targeted agents to invasive glioma cells. Transgenic mice lacking P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp) were used to study efflux of erlotinib at the BBB. A U87 rat xenograft model of GBM was used to investigate the regional distribution of erlotinib to the tumor, and brain regions surrounding the tumor. The effect of concurrent administration of elacridar on regional tumor distribution of erlotinib was evaluated. We show that erlotinib transport across an intact BBB is significantly restricted due to P-gp- and Bcrp-mediated efflux transport. We then show that the BBB is sufficiently intact in areas of brain adjacent to the tumor core to significantly restrict erlotinib delivery. Inhibition of P-gp and Bcrp by the dual inhibitor elacridar dramatically increased erlotinib delivery to the tumor core, rim, and normal brain. These results provide conclusive evidence of the impact that active efflux at the BBB has on the delivery of molecularly targeted therapy to different tumor regions in glioma. These data also support the possibility that the repeated failure of clinical trials of new drugs for gliomas may be in part due to a failure to achieve effective concentrations in invasive tumor cells that reside behind an intact BBB. PMID:23014761

  9. Irradiation of necrotic cancer cells, employed for pulsing dendritic cells (DCs), potentiates DC vaccine-induced antitumor immunity against high-grade glioma

    PubMed Central

    Vandenberk, Lien; Garg, Abhishek D.; Verschuere, Tina; Koks, Carolien; Belmans, Jochen; Beullens, Monique; Agostinis, Patrizia; De Vleeschouwer, Steven; Van Gool, Stefaan W.

    2016-01-01

    ABSTRACT Dendritic cell (DC)-based immunotherapy has yielded promising results against high-grade glioma (HGG). However, the efficacy of DC vaccines is abated by HGG-induced immunosuppression and lack of attention toward the immunogenicity of the tumor lysate/cells used for pulsing DCs. A literature analysis of DC vaccination clinical trials in HGG patients delineated the following two most predominantly applied methods for tumor lysate preparation: freeze-thaw (FT)-induced necrosis or FT-necrosis followed by X-ray irradiation. However, from the available clinical evidence, it is unclear which of both methodologies has superior immunogenic potential. Using an orthotopic HGG murine model (GL261-C57BL/6), we observed that prophylactic vaccination with DCs pulsed with irradiated FT-necrotic cells (compared to FT-necrotic cells only) prolonged overall survival by increasing tumor rejection in glioma-challenged mice. This was associated, both in prophylactic and curative vaccination setups, with an increase in brain-infiltrating Th1 cells and cytotoxic T lymphocytes (CTL), paralleled by a reduced accumulation of regulatory T cells, tumor-associated macrophages (TAM) and myeloid-derived suppressor cells (MDSC). Further analysis showed that irradiation treatment of FT-necrotic cells considerably increased the levels of carbonylated proteins — a surrogate-marker of oxidation-associated molecular patterns (OAMPs). Through further application of antioxidants and hydrogen peroxide, we found a striking correlation between the amount of lysate-associated protein carbonylation/OAMPs and DC vaccine-mediated tumor rejection capacity thereby suggesting for the first time a role for protein carbonylation/OAMPs in at least partially mediating antitumor immunity. Together, these data strongly advocate the use of protein oxidation-inducing modalities like irradiation for increasing the immunogenicity of tumor lysate/cells used for pulsing DC vaccines. PMID:27057467

  10. Quercetin-induced downregulation of phospholipase D1 inhibits proliferation and invasion in U87 glioma cells

    SciTech Connect

    Park, Mi Hee; Min, Do Sik

    2011-09-09

    Highlights: {yields} Quercetin, a bioactive flavonoid, suppresses expression and enzymatic activity of phospholipase D1. {yields} Quercetin abolishes NFkB-induced phospholipase D1 expression via inhibition of NFkB transactivation. {yields} Quercetin-induced suppression of phospholipase D1 inhibits invasion and proliferation of human glioma cells. -- Abstract: Phospholipase D (PLD) has been recognized as a regulator of cell proliferation and tumorigenesis, but little is known about the molecules regulating PLD expression. Thus, the identification of small molecules inhibiting PLD expression would be an important advance in PLD-mediated physiology. Quercetin, a ubiquitous bioactive flavonoid, is known to inhibit proliferation and induce apoptosis in a variety of cancer cells. In the present study, we examined the effect of quercetin on the expression of PLD in U87 glioma cells. Quercetin significantly suppressed the expression of PLD1 at the transcriptional level. Moreover, quercetin abolished the protein expression of PLD1 in a time and dose-dependent manner, as well as inhibited PLD activity. Quercetin suppressed NF{kappa}B-induced PLD1 expression via inhibition of NFkB transactivation. Furthermore, quercetin inhibited activation and invasion of metalloproteinase-2 (MMP-2), a key modulator of glioma cell invasion, induced by phosphatidic acid (PA), a product of PLD activity. Taken together these data demonstrate that quercetin abolishes PLD1 expression and subsequently inhibits invasion and proliferation of glioma cells.

  11. KCa3.1 channel inhibition sensitizes malignant gliomas to temozolomide treatment

    PubMed Central

    D'Alessandro, Giuseppina; Grimaldi, Alfonso; Chece, Giuseppina; Porzia, Alessandra; Esposito, Vincenzo; Santoro, Antonio; Salvati, Maurizio; Mainiero, Fabrizio; Ragozzino, Davide; Angelantonio, Silvia Di; Wulff, Heike; Catalano, Myriam; Limatola, Cristina

    2016-01-01

    Malignant gliomas are among the most frequent and aggressive cerebral tumors, characterized by high proliferative and invasive indexes. Standard therapy for patients, after surgery and radiotherapy, consists of temozolomide (TMZ), a methylating agent that blocks tumor cell proliferation. Currently, there are no therapies aimed at reducing tumor cell invasion. Ion channels are candidate molecular targets involved in glioma cell migration and infiltration into the brain parenchyma. In this paper we demonstrate that: i) blockade of the calcium-activated potassium channel KCa3.1 with TRAM-34 has co-adjuvant effects with TMZ, reducing GL261 glioma cell migration, invasion and colony forming activity, increasing apoptosis, and forcing cells to pass the G2/M cell cycle phase, likely through cdc2 de-phosphorylation; ii) KCa3.1 silencing potentiates the inhibitory effect of TMZ on glioma cell viability; iii) the combination of TMZ/TRAM-34 attenuates the toxic effects of glioma conditioned medium on neuronal cultures, through a microglia dependent mechanism since the effect is abolished by clodronate-induced microglia killing; iv) TMZ/TRAM-34 co-treatment increases the number of apoptotic tumor cells, and the mean survival time in a syngeneic mouse glioma model (C57BL6 mice implanted with GL261 cells); v) TMZ/TRAM-34 co-treatment reduces cell viability of GBM cells and cancer stem cells (CSC) freshly isolated from patients. Taken together, these data suggest a new therapeutic approach for malignant glioma, targeting both glioma cell proliferating and migration, and demonstrate that TMZ/TRAM-34 co-treatment affects both glioma cells and infiltrating microglia, resulting in an overall reduction of tumor cell progression. PMID:27096953

  12. Cannabidiol inhibits human glioma cell migration through a cannabinoid receptor-independent mechanism

    PubMed Central

    Vaccani, Angelo; Massi, Paola; Colombo, Arianna; Rubino, Tiziana; Parolaro, Daniela

    2005-01-01

    We evaluated the ability of cannabidiol (CBD) to impair the migration of tumor cells stimulated by conditioned medium. CBD caused concentration-dependent inhibition of the migration of U87 glioma cells, quantified in a Boyden chamber. Since these cells express both cannabinoid CB1 and CB2 receptors in the membrane, we also evaluated their engagement in the antimigratory effect of CBD. The inhibition of cell was not antagonized either by the selective cannabinoid receptor antagonists SR141716 (CB1) and SR144528 (CB2) or by pretreatment with pertussis toxin, indicating no involvement of classical cannabinoid receptors and/or receptors coupled to Gi/o proteins. These results reinforce the evidence of antitumoral properties of CBD, demonstrating its ability to limit tumor invasion, although the mechanism of its pharmacological effects remains to be clarified. PMID:15700028

  13. The neurobiology of gliomas: from cell biology to the development of therapeutic approaches.

    PubMed

    Westphal, Manfred; Lamszus, Katrin

    2011-08-03

    Gliomas are the most common type of primary brain tumour and are often fast growing with a poor prognosis for the patient. Their complex cellular composition, diffuse invasiveness and capacity to escape therapies has challenged researchers for decades and hampered progress towards an effective treatment. Recent molecular characterization of tumour cells combined with new insights into cellular diversification that occurs during development, and the modelling of these processes in transgenic animals have enabled a more detailed understanding of the events that underlie gliomagenesis. Combining this enhanced understanding of the relationship between neural stem cell biology and the cell lineage relationships of tumour cells with model systems offers new opportunities to develop specific and effective therapies.

  14. Roles of sphingosine-1-phosphate (S1P) receptors in malignant behavior of glioma cells. Differential effects of S1P{sub 2} on cell migration and invasiveness

    SciTech Connect

    Young, Nicholas; Van Brocklyn, James R. . E-mail: james.vanbrocklyn@osumc.edu

    2007-05-01

    Sphingosine-1-phosphate (S1P) is a bioactive lipid that signals through a family of five G-protein-coupled receptors, termed S1P{sub 1-5}. S1P stimulates growth and invasiveness of glioma cells, and high expression levels of the enzyme that forms S1P, sphingosine kinase-1, correlate with short survival of glioma patients. In this study we examined the mechanism of S1P stimulation of glioma cell proliferation and invasion by either overexpressing or knocking down, by RNA interference, S1P receptor expression in glioma cell lines. S1P{sub 1}, S1P{sub 2} and S1P{sub 3} all contribute positively to S1P-stimulated glioma cell proliferation, with S1P{sub 1} being the major contributor. Stimulation of glioma cell proliferation by these receptors correlated with activation of ERK MAP kinase. S1P{sub 5} blocks glioma cell proliferation, and inhibits ERK activation. S1P{sub 1} and S1P{sub 3} enhance glioma cell migration and invasion. S1P{sub 2} inhibits migration through Rho activation, Rho kinase signaling and stress fiber formation, but unexpectedly, enhances glioma cell invasiveness by stimulating cell adhesion. S1P{sub 2} also potently enhances expression of the matricellular protein CCN1/Cyr61, which has been implicated in tumor cell adhesion, and invasion as well as tumor angiogenesis. A neutralizing antibody to CCN1 blocked S1P{sub 2}-stimulated glioma invasion. Thus, while S1P{sub 2} decreases glioma cell motility, it may enhance invasion through induction of proteins that modulate glioma cell interaction with the extracellular matrix.

  15. Wortmannin potentiates the combined effect of etoposide and cisplatin in human glioma cells.

    PubMed

    Pastwa, Elzbieta; Poplawski, Tomasz; Lewandowska, Urszula; Somiari, Stella B; Blasiak, Janusz; Somiari, Richard I

    2014-08-01

    The combination of etoposide and cisplatin represents a common modality for treating of glioma patients. These drugs directly and indirectly produce the most lethal DNA double-stand breaks (DSB), which are mainly repaired by non-homologous DNA end joining (NHEJ). Drugs that can specifically inhibit the kinase activity of the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), the major component of NHEJ, are of special interest in cancer research. These small molecule inhibitors can effectively enhance the efficacy of current cancer treatments that generate DNA damage. In this study, we investigated the effect of DNA-PKcs inhibitor, wortmannin, on the cytotoxic mechanism of etoposide and cisplatin in MO59K and MO59J human glioblastoma cell lines. These cell lines are proficient and deficient in DNA-PKcs, respectively. Wortmannin synergistically increased the cytotoxicity of cisplatin and etoposide, when combined, in NHEJ-proficient MO59K cells. Surprisingly, wortmannin sensitizing effect was also observed in DNA-PKcs-deficient MO59J cells. These data suggest that wortmannin sensitization to etoposide and cisplatin in human glioma cells is mediated by inhibition of not only DNA-PKcs activity but other enzymes from PI3-K family, e.g. ATM and ATR. A concentration-dependent increase in etoposide and cisplatin-induced DSB levels was potentiated by inhibitor in both cell lines. Moreover, drug-induced accumulation in the G2/M checkpoint and S-phase was increased by wortmannin. Wortmannin significantly inhibited drug-induced DSB repair in MO59 cells and this effect was more pronounced in MO59J cells. We conclude that the mechanism of wortmannin potentiation of etoposide and cisplatin cytotoxicity involves DSBs induction, DSBs repair inhibition, G2/M checkpoint arrest and inhibition of not only DNA-PKcs activity.

  16. GPR56 is a GPCR that is overexpressed in gliomas and functions in tumor cell adhesion.

    PubMed

    Shashidhar, Sumana; Lorente, Gustavo; Nagavarapu, Usha; Nelson, April; Kuo, Jane; Cummins, Jeramiah; Nikolich, Karoly; Urfer, Roman; Foehr, Erik D

    2005-03-03

    GPR56 (also known as TM7XN1) is a newly discovered orphan G-protein-coupled receptor (GPCR) of the secretin family that has a role in the development of neural progenitor cells and has been linked to developmental malformations of the human brain. GPR56 diverges from other secretin-like family members in that it has an extremely large N-terminal extracellular region (381 amino acids) and contains a novel feature among this new subclass, consisting of four cysteine residues that define a GPCR proteolytic site (GPS motif) located just before the first transmembrane spanning domain. The rest of the amino-terminal domain contains a large number of possible N- and O-linked glycosylation sites similar to mucin-like proteins. These features suggest a role in cell-cell, or cell-matrix interactions. Here, we demonstrate upregulation of GPR56 in glioblastoma multiforme tumors using functional genomics. Immunohistochemistry studies confirmed the expression of GPR56 protein in a majority of glioblastoma/astrocytoma tumor samples with undetectable levels of expression in normal adult brain tissue. Immunofluorescence analysis of human glioma cells using anti-GPR56 antibodies demonstrate that GPR56 is expressed on the leading edge of membrane filopodia and colocalizes with alpha-actinin. Purified recombinant GPR56 extracellular domain protein inhibits glioma cell adhesion and causes abnormal cytoskeletal morphology and cell rounding. These results indicate that the extracellular domain may compete for unidentified ligand(s), and block the normal function of GPR56 in cell attachment. In reporter assays, overexpression of GPR56 activates the NF-kappaB, PAI-1 and TCF transcriptional response elements. These pathways have been implicated in cytoskeletal signaling, adhesion and tumor biology. The above results indicate that GPR56 serves as an adhesion GPCR and is involved in adhesion signaling.

  17. Long non-coding RNA ZFAS1 is an unfavourable prognostic factor and promotes glioma cell progression by activation of the Notch signaling pathway.

    PubMed

    Gao, Kai; Ji, Zhiwu; She, Kun; Yang, Qingyan; Shao, Lianbin

    2017-03-01

    Survival of patients with glioma remains poor, which is largely attributed to active carcinogenesis. Accumulating evidence indicates that long non-coding RNAs (lncRNAs) play key roles in tumor initiation and progression. However, the function of lncRNA ZFAS1 in glioma is still unclear. In the current study, we found that ZFAS1 was upregulated in glioma tissues and cell lines. High ZFAS1 expression in glioma tissues was significantly correlated with advanced tumor stage and poor overall survival. Furthermore, in vitro assays demonstrated that ZFAS1 inhibition significantly suppressed glioma cell proliferation, migration and invasion. Importantly, we further confirmed that epithelial-mesenchymal transition (EMT) and the Notch signaling pathway was inactivated in the glioma cells after ZFAS1 knockdown. Thus, our findings indicated that ZFAS1 could exhibit a tumor oncogenic role in glioma progression by regulating EMT and Notch signaling pathway. LncRNA ZFAS1 might serve as a therapeutic target for the treatment of glioma patients.

  18. PRRT2 inhibits the proliferation of glioma cells by modulating unfolded protein response pathway.

    PubMed

    Bi, Guanghui; Yan, Jingfeng; Sun, Shuzhen; Qu, Xinhua

    2017-02-10

    Accumulating studies reported mutations in the gene encoding the proline-rich transmembrane protein 2 (PRRT2) to be causative for several paroxysmal neurological disorders, including paroxysmal kinesigenic dyskinesia (PKD), PKD combined with infantile seizures (ICCA), and benign familial infantile seizures (BFIS). However, the impact of PRRT2 in tumorigenesis is not known. Based on a large-scale data analysis, we found that PRRT2 was down-regulated in glioma tumor tissues compared with normal brain tissue. Dysregulation of PRRT2 was not induced by mutation, copy number variation and epigenetic modification, but modulated by microRNA-30a-5p. Overexpression of PRRT2 strongly impaired the cell viability and promoted cell apoptosis and these anti-tumor effects could be largely reversed by microRNA-30a-5p. Mechanistically, PRRT2 expression was closely correlated genes involved in unfolded protein response (UPR) pathway and introduction of PRRT2 inhibited gene expression in the three branches of UPR, including PERK axis, IRE1 axis and ATF6 axis. Taken together, our findings identify PRRT2 as a tumor suppressor in glioma and provide a promising target for potential therapeutic intervention.

  19. Inhibiting Heat Shock Proteins Can Potentiate the Cytotoxic Effect of Cannabidiol in Human Glioma Cells.

    PubMed

    Scott, Katherine A; Dennis, Jayne L; Dalgleish, Angus G; Liu, Wai M

    2015-11-01

    Cannabinoids possess a number of characteristics that make them putative anticancer drugs, and their value as such is currently being explored in a number of clinical studies. To further understand the roles that cannabinoids may have, we performed gene expression profiling in glioma cell lines cultured with cannabidiol (CBD) and/or Δ9-tetrahydrocannabinol (THC), and pursued targets identified by this screening. Results showed that a large number of genes belonging to the heat shock protein (HSP) super-family were up-regulated following treatment, specifically with CBD. Increases were observed both at the gene and protein levels and arose as a consequence of increased generation of ROS by CBD, and correlated with an increase in a number of HSP client proteins. Furthermore, increases impeded the cytotoxic effect of CBD; an effect that was improved by co-culture with pharmacalogical inhibitors of HSPs. Similarly, culturing glioma cells with CBD and HSP inhibitors increased radiosensitivity when compared to CBD-alone. Taken together, these data indicate that the cytotoxic effects of CBD can be diminished by HSPs that indirectly rise as a result of CBD use, and that the inclusion of HSP inhibitors in CBD treatment regimens can enhance the overall effect.

  20. Short hairpin RNA targeting Notch2 inhibits U87 human glioma cell proliferation by inducing cell cycle arrest and apoptosis in vitro and in vivo

    PubMed Central

    LI, XUEZHEN; HE, XIN; TIAN, WEI; WANG, JIANZHEN

    2014-01-01

    Notch signaling has been reported to be oncogenic or tumor suppressive, depending on the tissue context. To investigate the effects of Notch2 knockdown on U87 human glioma cell proliferation in vitro and in vivo, and the associated mechanisms, U87 cells were stably transfected with p green fluorescent protein (GFP)-V-RS Notch2 short hairpin (sh) RNA plasmid and pGFP-V-RS scramble-shRNA plasmid. The former was referred to as the Notch2-shRNA group and the latter as the negative-shRNA group. mRNA and protein expression, cell proliferation, cell cycle and apoptosis were measured by reverse transcription-polymerase chain reaction, western blot analysis, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis and flow cytometry using propidium iodide, respectively. Tumor volume, tumor weight and cumulative survival rate were determined in a nude mouse xenograft tumor model. Notch2 mRNA and protein expression in the Notch2-shRNA group were reduced by 87.6 and 94.5% compared with the negative-shRNA group (P<0.001). Notch2 knockdown significantly inhibited U87 cell proliferation after three days of culture (P<0.05). Notch2 silencing induced cell cycle arrest at G0/G1 phase by upregulation of p21 protein expression and downregulation of mini chromosome maintenance complex 2 and cyclin-D1 protein expression. Furthermore, knockdown of Notch2 also induced U87 cell apoptosis. On day 50 after inoculation, tumor weight in the Notch2-shRNA group was significantly lower than that in the negative-shRNA group (0.55±0.10 vs. 1.23±0.52 g; P<0.01). The cumulative survival rate was significantly longer in the Notch2-shRNA group compared with the negative-shRNA group (log rank test P=0.01). In conclusion, Notch2 silencing inhibited U87 glioma cell proliferation by inducing cell cycle arrest and apoptosis in vitro and in vivo. Thus, Notch2 may be a key therapeutic target for the treatment of glioma. PMID:25323114

  1. Metformin treatment reduces temozolomide resistance of glioblastoma cells

    PubMed Central

    Lu, Guangrong; Xue, Haipeng; Kim, Dong H.

    2016-01-01

    It has been reported that metformin acts synergistically with temozolomide (TMZ) to inhibit proliferation of glioma cells including glioblastoma multiforme (GBM). However, the molecular mechanism underlying how metformin exerts its anti-cancer effects remains elusive. We used a combined experimental and bioinformatics approach to identify genes and complex regulatory/signal transduction networks that are involved in restoring TMZ sensitivity of GBM cells after metformin treatment. First, we established TMZ resistant GBM cell lines and found that the resistant cells regained TMZ sensitivity after metformin treatment. We further identified that metformin down-regulates SOX2 expression in TMZ-resistant glioma cells, reduces neurosphere formation capacity of glioblastoma cells, and inhibits GBM xenograft growth in vivo. Finally, the global gene expression profiling data reveals that multiple pathways are involved in metformin treatment related gene expression changes, including fatty acid metabolism and RNA binding and splicing pathways. Our work provided insight of the mechanisms on potential synergistic effects of TMZ and metformin in the treatment of glioblastoma, which will in turn yield potentially translational value for clinical applications. PMID:27791206

  2. Identification and characterization of estrogen receptor-related receptor alpha and gamma in human glioma and astrocytoma cells.

    PubMed

    Gandhari, Mukesh K; Frazier, Chester R; Hartenstein, Julia S; Cloix, Jean-Francois; Bernier, Michel; Wainer, Irving W

    2010-02-05

    The purpose of this study was to examine expression and function of estrogen receptor-related receptors (ERRs) in human glioma and astrocytoma cell lines. These estrogen receptor-negative cell lines expressed ERRalpha and ERRgamma proteins to varying degree in a cell context dependent manner, with U87MG glioma cells expressing both orphan nuclear receptors. Cell proliferation assays were performed in the presence of ERR isoform-specific agonists and antagonists, and the calculated EC(50) and IC(50) values were consistent with previous reported values determined in other types of cancer cell lines. Induction of luciferase expression under the control of ERR isoform-specific promoters was also observed in these cells. These results indicate that ERRalpha and ERRgamma are differentially expressed in these tumor cell lines and likely contribute to agonist-dependent ERR transcriptional activity.

  3. Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway

    SciTech Connect

    Zhou, Xiuping; Meng, Qingming; Xu, Xuebin; Zhi, Tongle; Shi, Qiong; Wang, Yong; Yu, Rutong

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer The expression levels of Bex2 markedly increased in glioma tissues. Black-Right-Pointing-Pointer Bex2 over-expression promoted cell proliferation, while its down-regulation inhibited cell growth. Black-Right-Pointing-Pointer Bex2 down-regulation promoted cell apoptosis via JNK/c-Jun signaling pathway. -- Abstract: The function of Bex2, a member of the Brain Expressed X-linked gene family, in glioma is controversial and its mechanism is largely unknown. We report here that Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase (JNK) pathway. The expression level of Bex2 is markedly increased in glioma tissues. We observed that Bex2 over-expression promotes cell proliferation, while down-regulation of Bex2 inhibits cell growth. Furthermore, Bex2 down-regulation promotes cell apoptosis and activates the JNK pathway; these effects were abolished by administration of the JNK specific inhibitor, (SP600125). Thus, Bex2 may be an important player during the development of glioma.

  4. Agonistic antibodies reveal the function of GPR56 in human glioma U87-MG cells.

    PubMed

    Ohta, Shigeyuki; Sakaguchi, Sayaka; Kobayashi, Yuki; Mizuno, Norikazu; Tago, Kenji; Itoh, Hiroshi

    2015-01-01

    GPR56 is a member of the adhesion G protein-coupled receptor (GPCR) and is highly expressed in parts of tumor cells. The involvement of GPR56 in tumorigenesis has been reported. We generated agonistic monoclonal antibodies against human GPR56 and analyzed the action and signaling pathway of GPR56. The antibodies inhibited cell migration through the Gq and Rho pathway in human glioma U87-MG cells. Co-immunoprecipitation analysis indicated that the interaction between the GPR56 extracellular domain and transmembrane domain was potentiated by agonistic antibodies. These results demonstrated that functional antibodies are invaluable tools for GPCR research and should open a new avenue for therapeutic treatment of tumors.

  5. Dexamethasone inhibits proliferation and stimulates ecto-5'-nucleotidase/CD73 activity in C6 rat glioma cell line.

    PubMed

    Bavaresco, Luci; Bernardi, Andressa; Braganhol, Elizandra; Wink, Márcia R; Battastini, Ana Maria Oliveira

    2007-08-01

    Malignant gliomas are the most common and devastating primary tumors of the adult central nervous system. Dexamethasone, a synthetic glucocorticoid, is commonly co-administered to control edema in the management of brain tumors during chemotherapy and radiotherapy. In the present study, the effect of dexamethasone on proliferation and ectonucleotidase activities in rat C6 glioma cell line was investigated. Dexamethasone concentrations ranging from 0.001 to 10 microM induced a time- and concentration-dependent inhibition of C6 rat glioma cell proliferation after 24, 48 and 72-h treatment. The tetrazolium reduction assay (MTT) indicated a reduction of in cell viability (44 +/- 7.6%) after 48-h treatment with 1 microM dexamethasone. Pretreatment with 10 microM of RU38486, an antagonist of glucocorticoid receptors, abolished the effect of 1 microM dexamethasone by 78 +/- 9.8% after 48 h of treatment, indicating that this action is mediated via the glucocorticoid receptor. Members of the E-NTPDase family and ecto-5'-nucleotidase/CD73 can modulate extracellular ATP degradation and adenosine formation, both of which have been described as proliferation factors. Treatment of C6 glioma cells for 48 h with 1 microM dexamethasone increased in 38 +/- 8.09% the AMP hydrolysis and in 3.7-fold the ecto-5'-nucleotidase/CD73 expression, suggesting an increase in adenosine formation and, therefore, a possible modulatory role in the elicitation of cell death responses. In addition, pretreatment with 5 microM GF 109203X, a protein kinase C (PKC) inhibitor, abolished the effect of dexamethasone on cell proliferation and on ecto-5'-NT activity, suggesting that dexamethasone could exert this action via PKC. The alterations in the catabolism of extracellular purines induced by dexamethasone treatment in glioma C6 cells could be related to its pharmacological effects.

  6. BIX01294, an inhibitor of histone methyltransferase, induces autophagy-dependent differentiation of glioma stem-like cells

    PubMed Central

    Ciechomska, Iwona Anna; Przanowski, Piotr; Jackl, Judyta; Wojtas, Bartosz; Kaminska, Bozena

    2016-01-01

    Glioblastoma (GBM) contains rare glioma stem-like cells (GSCs) with capacities of self-renewal, multi-lineage differentiation, and resistance to conventional therapy. Drug-induced differentiation of GSCs is recognized as a promising approach of anti-glioma therapy. Accumulating evidence suggests that unique properties of stem cells depend on autophagy. Here we demonstrate that BIX01294, an inhibitor of a G9a histone methyltransferase (introducing H3K9me2 and H3K27me3 repressive marks) triggers autophagy in human glioma cells. Pharmacological or genetic inhibition of autophagy decreased LC3-II accumulation and GFP-LC3 punctation in BIX01294-treated cells. GSCs-enriched spheres originating from glioma cells and GBM patient-derived cultures express lower levels of autophagy related (ATG) genes than the parental glioma cell cultures. Typical differentiation inducers that upregulate neuronal and astrocytic markers in sphere cultures, increase the level of ATG mRNAs. G9a binds to the promoters of autophagy (LC3B, WIPI1) and differentiation-related (GFAP, TUBB3) genes in GSCs. Higher H3K4me3 (an activation mark) and lower H3K9me2 (the repressive mark) levels at the promoters of studied genes were detected in serum-differentiated cells than in sphere cultures. BIX01294 treatment upregulates the expression of autophagy and differentiation-related genes in GSCs. Pharmacological inhibition of autophagy decreases GFAP and TUBB3 expression in BIX01294-treated GSCs suggesting that BIX01294-induced differentiation of GSCs is autophagy-dependent. PMID:27934912

  7. Transfection of C6 Glioma Cells with Connexin 43 cDNA: Analysis of Expression, Intercellular Coupling, and Cell Proliferation

    NASA Astrophysics Data System (ADS)

    Zhu, D.; Caveney, S.; Kidder, G. M.; Naus, C. C. G.

    1991-03-01

    C6 glioma cells express low levels of the gap junction protein connexin 43 and its mRNA and display very weak dye coupling. When implanted into the rat cerebrum, these cells quickly give rise to a large glioma. To investigate the role of gap junctions in the tumor characteristics of these cells, we have used Lipofectin-mediated transfection to introduce a full-length cDNA encoding connexin 43. Several transfected clones were obtained that exhibited various amounts of connexin 43 mRNA transcribed from the inserted cDNA. Immunocytochemical analysis revealed an increase in the amount of connexin 43 immunoreactivity in the transfected cells, being localized at areas of intercellular contact as well as in the cytoplasm. The level of dye coupling was also assessed and found to correlate with the amount of connexin 43 mRNA. When cell proliferation was followed over several days, cells expressing the transfected cDNA grew more slowly than nontransfected cells. These transfected cells will be useful in examining the role of gap junctions in tumorigenesis.

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

    PubMed

    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.

  9. HPLC Analysis and Cytotoxicity of n-Butanol Extract from Glyphaea brevis Roots Against C6 Glioma Cells

    PubMed Central

    Konan, Koffi Marcel; Mamyrbekova-Bekro, Janat Akhanovna; Bakalara, Norbert; Virieux, David; Pirat, Jean-Luc; Bekro, Yves-Alain

    2014-01-01

    The n-butanol extract of the roots of Glyphaea brevis was analysed. HPLC analysis suggested the presence of phenolic compounds like protocatechuic acid (PCA). The extract showed moderate cytotoxic activity against C6 glioma cells (EC50 > 1 mg/ml). PMID:24634849

  10. Artemether Combined with shRNA Interference of Vascular Cell Adhesion Molecule-1 Significantly Inhibited the Malignant Biological Behavior of Human Glioma Cells

    PubMed Central

    Wang, Ping; Xue, Yi-Xue; Yao, Yi-Long; Yu, Bo; Liu, Yun-Hui

    2013-01-01

    Artemether is the derivative extracted from Chinese traditional herb and originally used for malaria. Artemether also has potential therapeutic effects against tumors. Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with malignancy of gliomas. In this work, we investigated the role and mechanism of artemether combined with shRNA interference of VCAM-1 (shRNA-VCAM-1) on the migration, invasion and apoptosis of glioma cells. U87 human glioma cells were treated with artemether at various concentrations and shRNA interfering technology was employed to silence the expression of VCAM-1. Cell viability, migration, invasiveness and apoptosis were assessed with MTT, wound healing, Transwell and Annexin V-FITC/PI staining. The expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and phosphorylated Akt (p-Akt) was checked by Western blot assay. Results showed that artemether and shRNA-VCAM-1 not only significantly inhibited the migration, invasiveness and expression of MMP-2/9 and p-Akt, but also promoted the apoptosis of U87 cells. Combined treatment of both displayed the maximum inhibitory effects on the malignant biological behavior of glioma cells. Our work revealed the potential therapeutic effects of artemether and antiVCAM-1 in the treatments of gliomas. PMID:23593320

  11. Rapid and label-free classification of human glioma cells by infrared spectroscopic imaging.

    PubMed

    Steiner, Gerald; Küchler, Saskia; Hermann, Andreas; Koch, Edmund; Salzer, Reiner; Schackert, Gabriele; Kirsch, Matthias

    2008-12-01

    The discrimination of cell types is a crucial task in cell biology. Available techniques, based on an irreversible treatment of the cells, do not allow a sensitive label-free characterization under in situ conditions. Infrared spectroscopic imaging is a new and useful tool for studying individual cells. It has established itself as a powerful method to probe the molecular composition and to indicate the biochemistry of cells. Monolayers of cultivated U343, T1115 and T508 human glioma cells were characterized using infrared spectroscopic imaging. A classification algorithm based on linear discriminant analysis was developed to distinguish different cells without labeling. The classification is based upon spectral features which mainly arise from proteins, nucleic acids, and cholesterol. An accuracy of 91% and 84% was obtained for cells of U343 and T1115, respectively. Cells of the T508 cell line exhibit some misclassifications resulting in a lower accuracy rate of 73%. As the results demonstrate, the potential of infrared spectroscopic imaging method to assess the overall molecular composition of cells in a non-destructive manner opens the possibility to characterize cells on a molecular level without labels or an irreversible treatment.

  12. ET-05INTRANASAL DELIVERY OF NEURAL STEM CELLS LOADED WITH ONCOLYTIC ADENOVIRUS EXTENDS SURVIVAL OF MICE WITH INTRACRANIAL GLIOMA

    PubMed Central

    Balyasnikova, Irina; Dey, Mahua; Tobias, Alex; Kanojia, Deepak; Lee, Gina; Han, Yu; Zhang, Lingjiao; Ahmed, Atique; Aboody, Karen; Lesniak, Maciej

    2014-01-01

    Glioblastoma multiforme (GBM), the most common adult primary brain tumor, is in need of better and effective therapeutic options. In this study, we hypothesized that neural stem cells (NSCs) loaded with CRAd-S-pK7 oncolytic adenovirus (OV) can be successfully delivered via nasal application (IN) and will impart therapeutic efficacy in a murine model of human glioma. Recently, we demonstrated that radiation therapy increases the expression of CXCL12 in glioma xenografts, thus contributing to the enhanced migration of stem cells to the tumor site. We now show that hypoxic preconditioning of NSCs for 24h (1% oxygen) results in the two-fold increase of the CXCR4 expression on the surface of NSCs and doubles the rate of their migration towards glioma cells (p < 0.001) compared to untreated group. Hypoxic preconditioning of NSCs did not alter the OV replication as measured by E1A copy number. For in vivo studies, a patient derived GBM43 glioma cells were intracranially inoculated in nude mice. One week later, mice were treated with fractioned dose of irradiation at 2Gy for 5 days. NSCs (5x105) cultured under normoxic and hypoxic conditions were loaded with OV at 50 viral particles per cell, and IN inoculated 24h following the completion of the radiation. Kaplan-Meier survival analysis demonstrated that irradiation resulted in 44% improvement (p < 0.001) in median survival versus non-treated group. Survival of irradiated mice was not affected by either NSC's or OV-loaded NSCs, but was extended (p < 0.05) another 25% in the group of animals treated with OV-loaded NSCs cultured under hypoxic conditions. Thus, our data further validate the IN delivery as a novel route for the stem cell-based anti-glioma therapy, and suggest that modification of NSCs by enhancing their ability to migrate might significantly increase their therapeutic potential for IN delivery to target GBM.

  13. β-Elemene Selectively Inhibits the Proliferation of Glioma Stem-Like Cells Through the Downregulation of Notch1.

    PubMed

    Feng, Hai-Bin; Wang, Jing; Jiang, Hao-Ran; Mei, Xin; Zhao, Yi-Ying; Chen, Fu-Rong; Qu, Yue; Sai, Ke; Guo, Cheng-Cheng; Yang, Qun-Ying; Zhang, Zong-Ping; Chen, Zhong-Ping

    2017-03-01

    Glioma is the most frequent primary central nervous system tumor. Although the current first-line medicine, temozolomide (TMZ), promotes patient survival, drug resistance develops easily. Thus, it is important to investigate novel therapeutic reagents to solidify the treatment effect. β-Elemene (bELE) is a compound from a Chinese herb whose anticancer effect has been shown in various types of cancer. However, its role in the inhibition of glioma stem-like cells (GSLCs) has not yet been reported. We studied both the in vitro and the in vivo inhibitory effect of bELE and TMZ in GSLCs and parental cells and their combined effects. The molecular mechanisms were also investigated. We also optimized the delivery methods of bELE. We found that bELE selectively inhibits the proliferation and sphere formation of GSLCs, other than parental glioma cells, and TMZ exerts its effects on parental cells instead of GSLCs. The in vivo data confirmed that the combination of bELE and TMZ worked better in the xenografts of GSLCs, mimicking the situation of tumorigenesis of human cancer. Notch1 was downregulated with bELE treatment. Our data also demonstrated that the continuous administration of bELE produces an ideal effect to control tumor progression. Our findings have demonstrated, for the first time, that bELE could compensate for TMZ to kill both GSLCs and nonstem-like cancer cells, probably improving the prognosis of glioma patients tremendously. Notch1 might be a downstream target of bELE. Therefore, our data shed light on improving the outcomes of glioma patients by combining bELE and TMZ. Stem Cells Translational Medicine 2017;6:830-839.

  14. Temozolomide and carmustine cause large-scale heterochromatin reorganization in glioma cells.

    PubMed

    Papait, Roberto; Magrassi, Lorenzo; Rigamonti, Dorotea; Cattaneo, Elena

    2009-02-06

    Temozolomide (TMZ) and carmustine (BCNU), cancer-drugs usually used in the treatment of gliomas, are DNA-methylating agents producing O6-methylguanine. It has been shown that 06-methylguanine triggers DNA mismatch repair and in turn induce apoptosis and senescence, respectively, over a 4 and 6 days period [Y. Hirose, M.S. Berger, R.O. Pieper, p53 effects both the duration of G2/M arrest and the fate of temozolomide-treated human glioblastoma cells, Cancer Res. 61 (2001) 1957-1963; W. Roos, M. Baumgartner, B. Kaina, Apoptosis triggered by DNA damage O6-methylguanine in human lymphocytes requires DNA replication and is mediated by p53 and Fas/CD95/Apo-1, Oncogene 23 (2004) 359-367]. Here we show that TMZ and BCNU have an earlier effect on nuclear organization and chromatin structure. In particular, we report that TMZ and BCNU induce clustering of pericentromeric heterochromatin regions and increase the amount of heterochromatic proteins MeCP2 and HP1alpha bound to chromatin. These drugs also decrease global levels of histone H3 acetylation and increase levels of histone H3 trimethylated on lysine 9 (H3-triMeK9). These events precede the senescence status. We conclude that TMZ and BCNU efficacy in glioma treatment may implicate a first event characterized by changes in heterochromatin organization and its silencing which is then followed by apoptosis and senescence.

  15. Lactoferrin conjugated iron oxide nanoparticles for targeting brain glioma cells in magnetic particle imaging

    NASA Astrophysics Data System (ADS)

    Tomitaka, Asahi; Arami, Hamed; Gandhi, Sonu; Krishnan, Kannan M.

    2015-10-01

    Magnetic Particle Imaging (MPI) is a new real-time imaging modality, which promises high tracer mass sensitivity and spatial resolution directly generated from iron oxide nanoparticles. In this study, monodisperse iron oxide nanoparticles with median core diameters ranging from 14 to 26 nm were synthesized and their surface was conjugated with lactoferrin to convert them into brain glioma targeting agents. The conjugation was confirmed with the increase of the hydrodynamic diameters, change of zeta potential, and Bradford assay. Magnetic particle spectrometry (MPS), performed to evaluate the MPI performance of these nanoparticles, showed no change in signal after lactoferrin conjugation to nanoparticles for all core diameters, suggesting that the MPI signal is dominated by Néel relaxation and thus independent of hydrodynamic size difference or presence of coating molecules before and after conjugations. For this range of core sizes (14-26 nm), both MPS signal intensity and spatial resolution improved with increasing core diameter of nanoparticles. The lactoferrin conjugated iron oxide nanoparticles (Lf-IONPs) showed specific cellular internalization into C6 cells with a 5-fold increase in MPS signal compared to IONPs without lactoferrin, both after 24 h incubation. These results suggest that Lf-IONPs can be used as tracers for targeted brain glioma imaging using MPI.

  16. Temozolomide and carmustine cause large-scale heterochromatin reorganization in glioma cells

    SciTech Connect

    Papait, Roberto; Magrassi, Lorenzo; Rigamonti, Dorotea; Cattaneo, Elena

    2009-02-06

    Temozolomide (TMZ) and carmustine (BCNU), cancer-drugs usually used in the treatment of gliomas, are DNA-methylating agents producing O6-methylguanine. It has been shown that 06-methylguanine triggers DNA mismatch repair and in turn induce apoptosis and senescence, respectively, over a 4 and 6 days period [Y. Hirose, M.S. Berger, R.O. Pieper, p53 effects both the duration of G2/M arrest and the fate of temozolomide-treated human glioblastoma cells, Cancer Res. 61 (2001) 1957-1963; W. Roos, M. Baumgartner, B. Kaina, Apoptosis triggered by DNA damage O6-methylguanine in human lymphocytes requires DNA replication and is mediated by p53 and Fas/CD95/Apo-1, Oncogene 23 (2004) 359-367]. Here we show that TMZ and BCNU have an earlier effect on nuclear organization and chromatin structure. In particular, we report that TMZ and BCNU induce clustering of pericentromeric heterochromatin regions and increase the amount of heterochromatic proteins MeCP2 and HP1{alpha} bound to chromatin. These drugs also decrease global levels of histone H3 acetylation and increase levels of histone H3 trimethylated on lysine 9 (H3-triMeK9). These events precede the senescence status. We conclude that TMZ and BCNU efficacy in glioma treatment may implicate a first event characterized by changes in heterochromatin organization and its silencing which is then followed by apoptosis and senescence.

  17. Irradiation With Carbon Ion Beams Induces Apoptosis, Autophagy, and Cellular Senescence in a Human Glioma-Derived Cell Line

    SciTech Connect

    Jinno-Oue, Atsushi; Shimizu, Nobuaki; Hamada, Nobuyuki; Wada, Seiichi; Tanaka, Atsushi; Shinagawa, Masahiko; Ohtsuki, Takahiro; Mori, Takahisa; Saha, Manujendra N.; Hoque, Ariful S.; Islam, Salequl; Kogure, Kimitaka; Funayama, Tomoo; Kobayashi, Yasuhiko

    2010-01-15

    Purpose: We examined biological responses of human glioma cells to irradiation with carbon ion beams (C-ions). Methods and Materials: A human glioma-derived cell line, NP-2, was irradiated with C-ions. Apoptotic cell nuclei were stained with Hoechst 33342. Induction of autophagy was examined either by staining cells with monodansylcadaverine (MDC) or by Western blotting to detect conversion of microtuble-associated protein light chain 3 (MAP-LC3) (LC3-I) to the membrane-bound form (LC3-II). Cellular senescence markers including induction of senescence-associated beta-galactosidase (SA-beta-gal) were examined. The mean telomere length of irradiated cells was determined by Southern blot hybridization. Expression of tumor suppressor p53 and cyclin/cyclin-dependent kinase inhibitor p21{sup WAF1/CIP1} in the irradiated cells was analyzed by Western blotting. Results: When NP-2 cells were irradiated with C-ions at 6 Gy, the major population of the cells died of apoptosis and autophagy. The residual fraction of attached cells (<1% of initially irradiated cells) could not form a colony: however, they showed a morphological phenotype consistent with cellular senescence, that is, enlarged and flattened appearance. The senescent nature of these attached cells was further indicated by staining for SA-beta-gal. The mean telomere length was not changed after irradiation with C-ions. Phosphorylation of p53 at serine 15 as well as the expression of p21{sup WAF1/CIP1} was induced in NP-2 cells after irradiation. Furthermore, we found that irradiation with C-ions induced cellular senescence in a human glioma cell line lacking functional p53. Conclusions: Irradiation with C-ions induced apoptosis, autophagy, and cellular senescence in human glioma cells.

  18. Combination of lentivirus-mediated silencing of PPM1D and temozolomide chemotherapy eradicates malignant glioma through cell apoptosis and cell cycle arrest

    PubMed Central

    Wang, Peng; Ye, Jing-An; Hou, Chong-Xian; Zhou, Dong; Zhan, Sheng-Quan

    2016-01-01

    Temozolomide (TMZ) is approved for use as first-line treatment for glioblastoma multiforme (GBM). However, GBM shows chemoresistance shortly after the initiation of treatment. In order to detect whether silencing of human protein phosphatase 1D magnesium dependent (PPM1D) gene could increase the effects of TMZ in glioma cells, glioma cells U87-MG were infected with lentiviral shRNA vector targeting PPM1D silencing. After PPM1D silencing was established, cells were treated with TMZ. The multiple functions of human glioma cells after PPM1D silencing and TMZ chemotherapy were detected by flow cytometry and MTT assay. Significantly differentially expressed genes were distinguished by microarray-based gene expression profiling and analyzed by gene pathway enrichment analysis and ontology assessment. Western blotting was used to establish the protein expression of the core genes. PPM1D gene silencing improves TMZ induced cell proliferation and induces cell apoptosis and cell cycle arrest. When PPM1D gene silencing combined with TMZ was performed in glioma cells, 367 genes were upregulated and 444 genes were downregulated compared with negative control. The most significant differential expression pathway was pathway in cancer and IGFR1R, PIK3R1, MAPK8 and EP300 are core genes in the network. Western blotting showed that MAPK8 and PIK3R1 protein expression levels were upregulated and RB1 protein expression was decreased. It was consistent with that detected in gene expression profiling. In conclusion, PPM1D gene silencing combined with TMZ eradicates glioma cells through cell apoptosis and cell cycle arrest. PIK3R1/AKT pathway plays a role in the multiple functions of glioma cells after PPM1D silencing and TMZ chemotherapy. PMID:27633132

  19. Neurosphere and adherent culture conditions are equivalent for malignant glioma stem cell lines

    PubMed Central

    Reyner, Karina; Deleyrolle, Loic; Millette, Sebastien; Azari, Hassan; Day, Bryan W.; Stringer, Brett W.; Boyd, Andrew W.; Johns, Terrance G.; Blot, Vincent; Duggal, Rohit; Reynolds, Brent A.

    2015-01-01

    Certain limitations of the neurosphere assay (NSA) have resulted in a search for alternative culture techniques for brain tumor-initiating cells (TICs). Recently, reports have described growing glioblastoma (GBM) TICs as a monolayer using laminin. We performed a side-by-side analysis of the NSA and laminin (adherent) culture conditions to compare the growth and expansion of GBM TICs. GBM cells were grown using the NSA and adherent culture conditions. Comparisons were made using growth in culture, apoptosis assays, protein expression, limiting dilution clonal frequency assay, genetic affymetrix analysis, and tumorigenicity in vivo. In vitro expansion curves for the NSA and adherent culture conditions were virtually identical (P=0.24) and the clonogenic frequencies (5.2% for NSA vs. 5.0% for laminin, P=0.9) were similar as well. Likewise, markers of differentiation (glial fibrillary acidic protein and beta tubulin III) and proliferation (Ki67 and MCM2) revealed no statistical difference between the sphere and attachment methods. Several different methods were used to determine the numbers of dead or dying cells (trypan blue, DiIC, caspase-3, and annexin V) with none of the assays noting a meaningful variance between the two methods. In addition, genetic expression analysis with microarrays revealed no significant differences between the two groups. Finally, glioma cells derived from both methods of expansion formed large invasive tumors exhibiting GBM features when implanted in immune-compromised animals. A detailed functional, protein and genetic characterization of human GBM cells cultured in serum-free defined conditions demonstrated no statistically meaningful differences when grown using sphere (NSA) or adherent conditions. Hence, both methods are functionally equivalent and remain suitable options for expanding primary high-grade gliomas in tissue culture. PMID:25806119

  20. Induction of G1 Cell Cycle Arrest in Human Glioma Cells by Salinomycin Through Triggering ROS-Mediated DNA Damage In Vitro and In Vivo.

    PubMed

    Zhao, Shi-Jun; Wang, Xian-Jun; Wu, Qing-Jian; Liu, Chao; Li, Da-Wei; Fu, Xiao-Ting; Zhang, Hui-Fang; Shao, Lu-Rong; Sun, Jing-Yi; Sun, Bao-Liang; Zhai, Jing; Fan, Cun-Dong

    2016-12-19

    Chemotherapy has always been one of the most effective ways in combating human glioma. However, the high metastatic potential and resistance toward standard chemotherapy severely hindered the chemotherapy outcomes. Hence, searching effective chemotherapy drugs and clarifying its mechanism are of great significance. Salinomycin an antibiotic shows novel anticancer potential against several human tumors, including human glioma, but its mechanism against human glioma cells has not been fully elucidated. In the present study, we demonstrated that salinomycin treatment time- and dose-dependently inhibited U251 and U87 cells growth. Mechanically, salinomycin-induced cell growth inhibition against human glioma was mainly achieved by induction of G1-phase arrest via triggering reactive oxide species (ROS)-mediated DNA damage, as convinced by the activation of histone, p53, p21 and p27. Furthermore, inhibition of ROS accumulation effectively attenuated salinomycin-induced DNA damage and G1 cell cycle arrest, and eventually reversed salinomycin-induced cytotoxicity. Importantly, salinomycin treatment also significantly inhibited the U251 tumor xenograft growth in vivo through triggering DNA damage-mediated cell cycle arrest with involvement of inhibiting cell proliferation and angiogenesis. The results above validated the potential of salinomycin-based chemotherapy against human glioma.

  1. The neuro-steroid, 5-androstene 3β,17α diol; induces endoplasmic reticulum stress and autophagy through PERK/eIF2α signaling in malignant glioma cells and transformed fibroblasts.

    PubMed

    Jia, Wentao; Loria, Roger M; Park, Margaret A; Yacoub, Adly; Dent, Paul; Graf, Martin R

    2010-12-01

    In this study, we identified a mechanism by which the neuro-steroid, 5-androstene 3β,17α diol (17α-AED) induces autophagy in human malignant glioma cells and transformed fibroblasts. 17α-AED treatment induced endoplasmic reticulum (ER) stress, identified by the partial activation of an unfolded protein response in T98G, U87MG, U251MG, LN-18, LN-229 and LN-Z308 glioma cell lines. In this regard, there were increased levels of CCAAT/enhancer-binding protein homologous protein (CHOP) and glucose-regulated protein of 78kDa transcripts but no splicing of X-box-binding protein 1 mRNA or processing of activating transcription factor-6 in glioma cells treated with the neuro-steroid. 17α-AED induced eukaryotic translational initiation factor 2α (eIF2α) phosphorylation in glioma cells which correlated with microtubule-associated protein-light chain 3 (LC3) conversion from LC3-I to -II. In transformed murine embryonic fibroblasts (MEFs) that are deficient of eIF2α function or T98G glioma cells transfected with a dominant-negative eIF2α construct, 17α-AED induced LC3 conversion was significantly reduced as compared to control cells. Neuro-steroid treatment caused the activation of the eIF2α kinase, protein kinase-like ER kinase (PERK) but not other eIF2α kinases in glioma cells. Moreover, eIF2α phosphorylation and LC3 conversion, in response to 17α-AED treatment, was blocked in MEFs that lacked PERK activity. T98G cells transfected with a dominant-negative PERK construct exhibited an attenuated response to neuro-steroid treatment in terms of decreases in: eIF2α activation; CHOP expression; the incidence of autophagy; and cytotoxicity. These results demonstrate that ER stress is linked to 17α-AED induced autophagy by PERK/eIF2α signaling in human malignant glioma cells and transformed fibroblasts.

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

    PubMed Central

    O’Brien, Rebecca; Jadus, Martin R.; Gillespie, G. Yancey; Cloud, Gretchen A.; Hoa, Neil T.; Langford, Catherine P.; Lopez, Richard D.; Harkins, Lualhati E.; Lamb Jr., Lawrence S.

    2015-01-01

    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. PMID:25955158

  3. 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

    NASA Astrophysics Data System (ADS)

    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.

  4. Resistance of glioma cells to nutrient-deprived microenvironment can be enhanced by CD133-mediated autophagy

    PubMed Central

    Cheng, Kai; Li, Peng; Han, Shuo; Li, Ruizhi; Su, Ming; Zeng, Wotan; Liu, Jinwen; Guo, Jinhai; Liu, Yinan; Zhang, Xiaoyan; He, Qihua; Shen, Li

    2016-01-01

    CD133 is a pentaspan transmembrane protein that can serve as a biomarker for cancer stem cells, although its biochemical mechanism remains unclear. Here we report that CD133 expression enhances glioma cell tolerance of a nutrient-deprived microenvironment. Under starvation conditions, CD133-positive cells exhibited higher survival and decreased levels of apoptosis. These changes were dependent on activation of autophagy-associated gene signaling and were impaired by the autophagic inhibitor chloroquine. Furthermore, rapamycin up-regulated the level of autophagy and inversely reduced CD133 expression. Immunofluorescence confirmed that starvation promoted release of CD133 from the plasma membrane to the cytoplasm, with CD133 also partially co-localizing with LC3 upon starvation. Additionally, CD133 partially co-localized with Beclin1, Atg5, and lysosomes, indicating that CD133 directly participates in the autophagosome membrane fusion process and ultimately undergoes lysosomal degradation. Collectively, our results demonstrate that CD133 contributes to cell survival by regulating autophagy, and that targeting CD133-linked signaling and autophagy may be useful in improving anti-cancer treatments. PMID:27780926

  5. TrkB-T1 regulates the RhoA signaling and actin cytoskeleton in glioma cells

    SciTech Connect

    Ohira, Koji; Homma, Koichi J.; Hirai, Hirohisa; Nakamura, Shun; Hayashi, Motoharu . E-mail: hayashi@pri.kyoto-u.ac.jp

    2006-04-14

    Recently, the truncated TrkB receptor, T1, has been reported to be involved in the control of cell morphology via the regulation of Rho proteins, through which T1 binds Rho guanine nucleotide dissociation inhibitor (Rho GDI) 1 and dissociates it in a brain-derived neurotrophic factor (BDNF)-dependent manner. However, it is unclear whether T1 signaling regulates the downstream of Rho signaling and the actin cytoskeleton. In this study, we investigated this question using C6 rat glioma cells, which express T1 endogenously. Rho GDI1 was dissociated from T1 in a BDNF-dependent manner, which also causes decreases in the activities of Rho-signaling molecules such as RhoA, Rho-associated kinase, p21-activated kinase, and extracellular-signal regulated kinase1/2. Moreover, BDNF treatment resulted in the disappearance of stress fibers in the cells treated with lysophosphatidic acid, an activator of RhoA, and in morphological changes in cells. Furthermore, a competitive assay with cyan fluorescent protein fusion proteins of T1-specific sequences reduced the effects of BDNF. These results suggest that T1 regulates the Rho-signaling pathways and the actin cytoskeleton.

  6. KCa3.1 inhibition switches the phenotype of glioma-infiltrating microglia/macrophages

    PubMed Central

    Grimaldi, A; D'Alessandro, G; Golia, M T; Grössinger, E M; Di Angelantonio, S; Ragozzino, D; Santoro, A; Esposito, V; Wulff, H; Catalano, M; Limatola, C

    2016-01-01

    Among the strategies adopted by glioma to successfully invade the brain parenchyma is turning the infiltrating microglia/macrophages (M/MΦ) into allies, by shifting them toward an anti-inflammatory, pro-tumor phenotype. Both glioma and infiltrating M/MΦ cells express the Ca2+-activated K+ channel (KCa3.1), and the inhibition of KCa3.1 activity on glioma cells reduces tumor infiltration in the healthy brain parenchyma. We wondered whether KCa3.1 inhibition could prevent the acquisition of a pro-tumor phenotype by M/MΦ cells, thus contributing to reduce glioma development. With this aim, we studied microglia cultured in glioma-conditioned medium or treated with IL-4, as well as M/MΦ cells acutely isolated from glioma-bearing mice and from human glioma biopsies. Under these different conditions, M/MΦ were always polarized toward an anti-inflammatory state, and preventing KCa3.1 activation by 1-[(2-Chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34), we observed a switch toward a pro-inflammatory, antitumor phenotype. We identified FAK and PI3K/AKT as the molecular mechanisms involved in this phenotype switch, activated in sequence after KCa3.1. Anti-inflammatory M/MΦ have higher expression levels of KCa3.1 mRNA (kcnn4) that are reduced by KCa3.1 inhibition. In line with these findings, TRAM-34 treatment, in vivo, significantly reduced the size of tumors in glioma-bearing mice. Our data indicate that KCa3.1 channels are involved in the inhibitory effects exerted by the glioma microenvironment on infiltrating M/MΦ, suggesting a possible role as therapeutic targets in glioma. PMID:27054329

  7. Myxoma Virus Infection Promotes NK Lysis of Malignant Gliomas In Vitro and In Vivo

    PubMed Central

    Ogbomo, Henry; Zemp, Franz J.; Lun, Xueqing; Zhang, Jiqing; Stack, Danuta; Rahman, Masmudur M.; Mcfadden, Grant; Mody, Christopher H.; Forsyth, Peter A.

    2013-01-01

    Myxoma virus (MYXV) is a well-established oncolytic agent against different types of tumors. MYXV is also known for its immunomodulatory properties in down-regulating major histocompatibility complex (MHC) I surface expression (via the M153R gene product, a viral E3-ubiquitin ligase) and suppressing T cell killing of infected target cells. MHC I down-regulation, however, favors NK cell activation. Brain tumors including gliomas are characterized by high MHC I expression with impaired NK activity. We thus hypothesized that MYXV infection of glioma cells will promote NK cell-mediated recognition and killing of gliomas. We infected human gliomas with MYXV and evaluated their susceptibility to NK cell-mediated cytotoxicity. MYXV enhanced NK cell-mediated killing of glioma cells (U87 cells, MYXV vs. Mock: 51.73% vs. 28.63%, P = .0001, t test; U251 cells, MYXV vs. Mock: 40.4% vs. 20.03%, P .0007, t test). Using MYXV M153R targeted knockout (designated vMyx-M153KO) to infect gliomas, we demonstrate that M153R was responsible for reduced expression of MHC I on gliomas and enhanced NK cell-mediated antiglioma activity (U87 cells, MYXV vs. vMyx-M153KO: 51.73% vs. 25.17%, P = .0002, t test; U251 cells, MYXV vs. vMyx-M153KO: 40.4% vs. 19.27, P = .0013, t test). Consequently, NK cell-mediated lysis of established human glioma tumors in CB-17 SCID mice was accelerated with improved mouse survival (log-rank P = .0072). These results demonstrate the potential for combining MYXV with NK cells to effectively kill malignant gliomas. PMID:23762498

  8. Myxoma virus infection promotes NK lysis of malignant gliomas in vitro and in vivo.

    PubMed

    Ogbomo, Henry; Zemp, Franz J; Lun, Xueqing; Zhang, Jiqing; Stack, Danuta; Rahman, Masmudur M; McFadden, Grant; Mody, Christopher H; Forsyth, Peter A

    2013-01-01

    Myxoma virus (MYXV) is a well-established oncolytic agent against different types of tumors. MYXV is also known for its immunomodulatory properties in down-regulating major histocompatibility complex (MHC) I surface expression (via the M153R gene product, a viral E3-ubiquitin ligase) and suppressing T cell killing of infected target cells. MHC I down-regulation, however, favors NK cell activation. Brain tumors including gliomas are characterized by high MHC I expression with impaired NK activity. We thus hypothesized that MYXV infection of glioma cells will promote NK cell-mediated recognition and killing of gliomas. We infected human gliomas with MYXV and evaluated their susceptibility to NK cell-mediated cytotoxicity. MYXV enhanced NK cell-mediated killing of glioma cells (U87 cells, MYXV vs. Mock: 51.73% vs. 28.63%, P = .0001, t test; U251 cells, MYXV vs. Mock: 40.4% vs. 20.03%, P .0007, t test). Using MYXV M153R targeted knockout (designated vMyx-M153KO) to infect gliomas, we demonstrate that M153R was responsible for reduced expression of MHC I on gliomas and enhanced NK cell-mediated antiglioma activity (U87 cells, MYXV vs. vMyx-M153KO: 51.73% vs. 25.17%, P = .0002, t test; U251 cells, MYXV vs. vMyx-M153KO: 40.4% vs. 19.27, P = .0013, t test). Consequently, NK cell-mediated lysis of established human glioma tumors in CB-17 SCID mice was accelerated with improved mouse survival (log-rank P = .0072). These results demonstrate the potential for combining MYXV with NK cells to effectively kill malignant gliomas.

  9. Delineating the Cytogenomic and Epigenomic Landscapes of Glioma Stem Cell Lines

    PubMed Central

    Baronchelli, Simona; Bentivegna, Angela; Redaelli, Serena; Riva, Gabriele; Butta, Valentina; Paoletta, Laura; Isimbaldi, Giuseppe; Miozzo, Monica; Tabano, Silvia; Daga, Antonio; Marubbi, Daniela; Cattaneo, Monica; Biunno, Ida; Dalprà, Leda

    2013-01-01

    Glioblastoma multiforme (GBM), the most common and malignant type of glioma, is characterized by a poor prognosis and the lack of an effective treatment, which are due to a small sub-population of cells with stem-like properties, termed glioma stem cells (GSCs). The term “multiforme” describes the histological features of this tumor, that is, the cellular and morphological heterogeneity. At the molecular level multiple layers of alterations may reflect this heterogeneity providing together the driving force for tumor initiation and development. In order to decipher the common “signature” of the ancestral GSC population, we examined six already characterized GSC lines evaluating their cytogenomic and epigenomic profiles through a multilevel approach (conventional cytogenetic, FISH, aCGH, MeDIP-Chip and functional bioinformatic analysis). We found several canonical cytogenetic alterations associated with GBM and a common minimal deleted region (MDR) at 1p36.31, including CAMTA1 gene, a putative tumor suppressor gene, specific for the GSC population. Therefore, on one hand our data confirm a role of driver mutations for copy number alterations (CNAs) included in the GBM genomic-signature (gain of chromosome 7- EGFR gene, loss of chromosome 13- RB1 gene, loss of chromosome 10-PTEN gene); on the other, it is not obvious that the new identified CNAs are passenger mutations, as they may be necessary for tumor progression specific for the individual patient. Through our approach, we were able to demonstrate that not only individual genes into a pathway can be perturbed through multiple mechanisms and at different levels, but also that different combinations of perturbed genes can incapacitate functional modules within a cellular networks. Therefore, beyond the differences that can create apparent heterogeneity of alterations among GSC lines, there’s a sort of selective force acting on them in order to converge towards the impairment of cell development and

  10. A novel manganese complex selectively induces malignant glioma cell death by targeting mitochondria.

    PubMed

    Geng, Ji; Li, Jing; Huang, Tao; Zhao, Kaidi; Chen, Qiuyun; Guo, Wenjie; Gao, Jing

    2016-09-01

    Despite advances in treatment, malignant glioma commonly exhibits recurrence, subsequently leading to a poor prognosis. As manganese (Mn) compounds can be transported by the transferrin‑transferrin receptor system, the present study synthesized and examined the potential use of Adpa‑Mn as a novel antitumor agent. Adpa‑Mn time and dose‑dependently inhibited U251 and C6 cell proliferation; however, it had little effect on normal astrocytes. Apoptosis was significantly elevated following treatment with Adpa‑Mn, as detected by chromatin condensation, Annexin V/propidium iodide staining, cytochrome c release from mitochondria to the cytoplasm, and the activation of caspases‑9, ‑7 and ‑3 and poly (ADP‑ribose) polymerase. In addition, Adpa‑Mn enhanced fluorescence intensity of monodansylcadaverine and elevated the expression levels of the autophagy‑related protein microtubule‑associated protein 1 light chain 3. Pretreatment with the autophagy inhibitors 3‑methyladenine and chloroquine enhanced Adpa‑Mn‑induced cell inhibition, thus indicating that autophagy has an essential role in this process. Furthermore, evidence of mitochondrial dysfunction was detected in the Adpa‑Mn‑treated group, including disrupted membrane potential, elevated levels of reactive oxygen species (ROS) and depleted adenosine triphosphate. Conversely, treatment with the mitochondrial permeability transition inhibitor cyclosporin A reversed Adpa‑Mn‑induced ROS production, mitochondrial damage and cell apoptosis, thus suggesting that Adpa‑Mn may target the mitochondria. Taken together, these data suggested that Adpa‑Mn may be considered for use as a novel anti‑glioma therapeutic option.

  11. Pertussis Toxin Is a Robust and Selective Inhibitor of High Grade Glioma Cell Migration and Invasion

    PubMed Central

    Wang, Lei; Natali, Letizia; Karimi-Mostowfi, Nicki; Brifault, Coralie; Gonias, Steven L.

    2016-01-01

    In high grade glioma (HGG), extensive tumor cell infiltration of normal brain typically precludes identifying effective margins for surgical resection or irradiation. Pertussis toxin (PT) is a multimeric complex that inactivates diverse Gi/o G-protein coupled receptors (GPCRs). Despite the broad continuum of regulatory events controlled by GPCRs, PT may be applicable as a therapeutic. We have shown that the urokinase receptor (uPAR) is a major driver of HGG cell migration. uPAR-initiated cell-signaling requires a Gi/o GPCR, N-formyl Peptide Receptor 2 (FPR2), as an essential co-receptor and is thus, PT-sensitive. Herein, we show that PT robustly inhibits migration of three separate HGG-like cell lines that express a mutated form of the EGF Receptor (EGFR), EGFRvIII, which is constitutively active. PT also almost completely blocked the ability of HGG cells to invade Matrigel. In the equivalent concentration range (0.01–1.0 μg/mL), PT had no effect on cell survival and only affected proliferation of one cell line. Neutralization of EGFRvIII expression in HGG cells, which is known to activate uPAR-initiated cell-signaling, promoted HGG cell migration. The increase in HGG cell migration, induced by EGFRvIII neutralization, was entirely blocked by silencing FPR2 gene expression or by treating the cells with PT. When U87MG HGG cells were cultured as suspended neurospheres in serum-free, growth factor-supplemented medium, uPAR expression was increased. HGG cells isolated from neurospheres migrated through Transwell membranes without loss of cell contacts; this process was inhibited by PT by >90%. PT also inhibited expression of vimentin by HGG cells; vimentin is associated with epithelial-mesenchymal transition and worsened prognosis. We conclude that PT may function as a selective inhibitor of HGG cell migration and invasion. PMID:27977780

  12. Intracellular free calcium mediates glioma cell detachment and cytotoxicity after photodynamic therapy.

    PubMed

    Hong, Xin; Jiang, Feng; Kalkanis, Steven N; Zhang, Zheng Gang; Zhang, Xuepeng; Zheng, Xuguang; Jiang, Hao; Chopp, Michael

    2009-09-01

    Photofrin photodynamic therapy (PDT) caused a dose-dependent decrease of enzymatic cell detachment by trypsin/ethylenediamine tetra-acetic acid (EDTA) in human glioma U251n and U87 cells. This happened coincidently with the increase of intracellular free calcium ([Ca(2+)](i)). Thapsigargin, which increased [Ca(2+)](i), induced further decrease in enzymatic cell detachment and increased cytotoxicity. Opposite effects were observed when 1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetra-acetic acid tetrakis, an intracellular Ca(2+) chelator, was used. PDT-induced changes in [Ca(2+)](i) and cell detachment were not blocked by calcium channel antagonists nickel (Ni(2+)) or nimodipine, nor were they altered when cells were irradiated in a buffer free from Ca(2+) and magnesium (Mg(2+)), suggesting that [Ca(2+)](i) is derived from the internal calcium stores. Decreased cell migration was observed after PDT, as assessed by chemotactic and wound-healing assays. Our findings indicated that internal calcium store-derived [Ca(2+)](i) plays an important role in PDT-induced enzymatic cell detachment decrease and cytotoxicity. Cell migration may be affected by these changes.

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

    PubMed

    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.

  14. Double Blockade of Glioma Cell Proliferation and Migration by Temozolomide Conjugated with NPPB, a Chloride Channel Blocker.

    PubMed

    Park, Miri; Song, Chiman; Yoon, Hojong; Choi, Kee-Hyun

    2016-03-16

    Glioblastoma is the most common and aggressive primary malignant brain tumor. Temozolomide (TMZ), a chemotherapeutic agent combined with radiation therapy, is used as a standard treatment. The infiltrative nature of glioblastoma, however, interrupts effective treatment with TMZ and increases the tendency to relapse. Voltage-gated chloride channels have been identified as crucial regulators of glioma cell migration and invasion by mediating cell shape and volume change. Accordingly, chloride current inhibition by 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), a chloride channel blocker, suppresses cell movement by diminishing the osmotic cell volume regulation. In this study, we developed a novel compound, TMZ conjugated with NPPB (TMZ-NPPB), as a potential anticancer drug. TMZ-NPPB blocked chloride currents in U373MG, a severely invasive human glioma cell line, and suppressed migration and invasion of U373MG cells. Moreover, TMZ-NPPB exhibited DNA modification activity similar to that of TMZ, and surprisingly showed remarkably enhanced cytotoxicity relative to TMZ by inducing apoptotic cell death via DNA damage. These findings indicate that TMZ-NPPB has a dual function in blocking both proliferation and migration of human glioma cells, thereby suggesting its potential to overcome challenges in current glioblastoma therapy.

  15. The Effect of Antitumor Glycosides on Glioma Cells and Tissues as Studied by Proton HR-MAS NMR Spectroscopy

    PubMed Central

    García-Álvarez, Isabel; Garrido, Leoncio; Romero-Ramírez, Lorenzo; Nieto-Sampedro, Manuel; Fernández-Mayoralas, Alfonso; Campos-Olivas, Ramón

    2013-01-01

    The effect of the treatment with glycolipid derivatives on the metabolic profile of intact glioma cells and tumor tissues, investigated using proton high resolution magic angle spinning (1H HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, is reported here. Two compounds were used, a glycoside and its thioglycoside analogue, both showing anti-proliferative activity on glioma C6 cell cultures; however, only the thioglycoside exhibited antitumor activity in vivo. At the drug concentrations showing anti-proliferative activity in cell culture (20 and 40 µM), significant increases in choline containing metabolites were observed in the 1H NMR spectra of the same intact cells. In vivo experiments in nude mice bearing tumors derived from implanted C6 glioma cells, showed that reduction of tumor volume was associated with significant changes in the metabolic profile of the same intact tumor tissues; and were similar to those observed in cell culture. Specifically, the activity of the compounds is mainly associated with an increase in choline and phosphocholine, in both the cell cultures and tumoral tissues. Taurine, a metabolite that has been considered a biomarker of apoptosis, correlated with the reduction of tumor volume. Thus, the results indicate that the mode of action of the glycoside involves, at least in part, alteration of phospholipid metabolism, resulting in cell death. PMID:24194925

  16. Expressions of glia maturation factor-β by tumor cells and endothelia correlate with neovascularization and poor prognosis in human glioma

    PubMed Central

    Chen, Cong; Su, Xiao-rui; Shi, Yu; Wu, Jin-rong; Zhang, Peng; Zhang, Xin-li; Cui, You-hong; Ping, Yi-fang; Bian, Xiu-wu

    2016-01-01

    Glia maturation factor-β (GMF-β) has been reported to promote glial differentiation, and act as a negative prognostic indicator in certain cancers. However, its roles in glioma progression remain unclear. Since neurogenesis and vasculogenesis were proved to share some common regulators during gliomagenesis, we aim to explore the potential impact of GMF-β on tumor neovascularization and patient survival in glioma. In this study, we first detected GMF-β expression not only in tumor cells but also in microvascular endothelia by double immunohistochemical staining. Both tumoral and endothelial GMF-β expression levels were positively correlated with tumor grade and microvessel density (MVD), while negatively associated with poor prognoses of the patients. Interestingly, multivariate analysis demonstrated that endothelial GMF-β expression level was the only independent predictor of progression-free and overall survival of glioma patients. The results of in vitro angiogenesis assay showed that GMF-β knockdown significantly inhibited tubulogenesis of human U87 glioblastoma cells. Furthermore, GMF-β knockdown suppressed tumor growth and the formation of human-CD31 positive (glioma cell-derived) microvessels in a mouse orthotopic U87 glioma model. Our results demonstrated that GMF-β is an important player in glioma progression via promoting neovascularization. GMF-β may therefore be a novel prognostic marker as well as a potential therapeutic target for glioma. PMID:26515590

  17. Comparative study of microtubule inhibitors--estramustine and natural podophyllotoxin conjugated PAMAM dendrimer on glioma cell proliferation.

    PubMed

    Sk, Ugir Hossain; Dixit, Deobrat; Sen, Ellora

    2013-10-01

    The synthetic estramustine (EM) and natural podophyllotoxin (PODO) anti-mitotic agents that inhibit tubulin polymerization are known anticancer agents. As low bioavailability limits their anticancer properties, we investigated whether conjugation with PAMAM dendrimer (D) could enhance the activity of D-EM and D-PODO by altering their release pattern. Release kinetics indicated synthesized conjugates to be stable against hydrolytic cleavage and showed sustained release characteristics. However, release of D-EM was slow compared to D-PODO conjugate. Antitumor effect of these conjugates on glioma cells revealed (i) increased cell death and cell cycle arrest (ii) decreased migration and (iii) increased tubulin depolymerization as compared to free drug. Importantly, the effects of natural PODO conjugate on glioma cell survival and migration is more pronounced than D-EM.

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

    PubMed

    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.

  19. Use of EF5 to Measure the Oxygen Level in Tumor Cells of Patients Undergoing Surgery or Biopsy for Newly Diagnosed Supratentorial Malignant Glioma

    ClinicalTrials.gov

    2013-01-15

    Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Oligodendroglioma; Adult Diffuse Astrocytoma; Adult Ependymoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Mixed Glioma; Adult Myxopapillary Ependymoma; Adult Oligodendroglioma; Adult Pilocytic Astrocytoma; Adult Pineal Gland Astrocytoma; Adult Subependymoma

  20. MiR-135a and MRP1 play pivotal roles in the selective lethality of phenethyl isothiocyanate to malignant glioma cells

    PubMed Central

    Zhang, Taolan; Shao, Yingying; Chu, Tang-Yuan; Huang, Hsuan-Shun; Liou, Yu-Ligh; Li, Qing; Zhou, Honghao

    2016-01-01

    Amounting evidence has demonstrated that phenethyl isothiocyanate (PEITC) is a strong inducer of reactive oxygen species (ROS) and functions as a selective killer to various human cancer cells. However, it remains obscure whether PEITC has potential selective lethality to malignant glioma cells. Thus in this study, we performed multiple analysis such as MTT assay, Hoechst 33258 staining, flow cytometry, foci formation, RT-PCR, Western blot, and transfection to explore the selective lethality of PEITC to malignant glioma cells and the underlying mechanisms. We found that PEITC induced a selective apoptosis and suppressed tumorigenicity and migration of malignant glioma cells. Furthermore, we found PEITC significantly induced GSH depletion, ROS production, caspase-9 and caspase-3 activation, and miR-135a upregulation in malignant glioma cells but not in normal cells. Moreover, PEITC activated the miR-135a-mitochondria dependent apoptosis pathway as demonstrated by downregulation of STAT6, SMAD5 and Bcl-xl while upregulation of Bax expression and Cytochrome-C release in malignant glioma cell lines but not in the immortalized human normal glial HEB cells. Correspondingly, the above PEITC-induced activation of the ROS-MiR-135a-Mitochondria dependent apoptosis pathways in malignant glioma was attenuated by pre-transfection with miR-135a inhibitor, pre-treatment with multidrug resistance-associated protein 1 (MRP1) inhibitor Sch B, or combination with glutathione (GSH). These results revealed that PEITC selectively induced apoptosis of malignant glioma cells through MRP1-mediated export of GSH to activate ROS-MiR-135a-Mitochondria dependent apoptosis pathway, suggesting a potential application of PEITC for treating glioma. PMID:27293991

  1. Vitamin D(3) enhances ATRA-mediated neurosteroid biosynthesis in human glioma GI-1 cells.

    PubMed

    Yagishita, Toshiaki; Kushida, Akira; Tamura, Hiroomi

    2012-09-01

    Emerging evidence indicates that vitamin D (VD) is an important modulator of brain development and function. To investigate whether VD modulates neurosteroid biosynthesis in neural cells, we investigated the effect of VD(3) on steroidogenic gene expression in human glioma GI-1 cells. We found that VD(3) enhanced CYP11A1 and 3β-hydroxysteroid dehydrogenase gene expression. The induction of CYP11A1 gene expression by VD(3) was dose- and incubation time-dependent. Calcipotriol, a VD(3) receptor (VDR) agonist, also induced CYP11A1 gene expression in GI-1 cells, indicating that VDR is involved in this induction. The induction of progesterone (PROG) de novo synthesis was observed along with the induction of steroidogenic genes by VD(3). Furthermore, VD(3) enhanced all-trans retinoic acid (ATRA)-induced CYP11A1 gene expression and PROG production. This suggests cooperative regulation of steroidogenic gene expression by the two fat-soluble vitamins, A and D. In addition, a mixed culture of neuronal IMR-32 cells and GI-1 cells treated with ATRA and VD(3) resulted in the induction of PROG-responsive gene expression in the IMR-32 cells. This result shows a paracrine action of PROG that is induced in and released by the GI-1 cells. The relationship between neurological dysfunction associated with VD deficiency and neurosteroid induction by VD is discussed.

  2. Dual Effect of Serum Amyloid A on the Invasiveness of Glioma Cells

    PubMed Central

    Knebel, Franciele Hinterholz; Albuquerque, Renata Chaves; Massaro, Renato Ramos; Maria-Engler, Silvya Stuchi; Campa, Ana

    2013-01-01

    Evidence sustains a role for the acute-phase protein serum amyloid A (SAA) in carcinogenesis and metastasis, and the protein has been suggested as a marker for tumor progression. Nevertheless, the demonstration of a direct activity of SAA on tumor cells is still incipient. We have investigated the effect of human recombinant SAA (rSAA) on two human glioma cell lines, A172 and T98G. rSAA stimulated the [3H]-thymidine incorporation of both lines, but had dual effects on migration and invasiveness which varied according to the cell line. In T98G, the rSAA increased migration and invasion behaviors whereas in A172 it decreased these behaviors. These findings agree with the effect triggered by rSAA on matrix metalloproteinases (MMPs) activities measured in a gelatinolytic assay. rSAA inhibited activity of both MMPs in A172 cells while increasing them in T98G cells. rSAA also affected the production of compounds present in the tumor microenvironment that orchestrate tumor progression, such as IL-8, the production of reactive oxygen species (ROS) and nitric oxide (NO). We also observed that both lines expressed all three of the isoforms of SAA: SAA1, SAA2, and SAA4. These data suggest that some tumor cells are responsive to SAA and, in these cases, SAA may have a role in cancer progression that varies according to the cell type. PMID:23533307

  3. The Inhibition by Oxaliplatin, a Platinum-Based Anti-Neoplastic Agent, of the Activity of Intermediate-Conductance Ca²⁺-Activated K⁺ Channels in Human Glioma Cells.

    PubMed

    Huang, Mei-Han; Huang, Yan-Ming; Wu, Sheng-Nan

    2015-01-01

    Oxaliplatin (OXAL) is a third-generation organoplatinum which is effective against advanced cancer cells including glioma cells. How this agent and other related compounds interacts with ion channels in glioma cells is poorly understood. OXAL (100 µM) suppressed the amplitude of whole-cell K+ currents (I(K)); and, either DCEBIO or ionomycin significantly reversed OXAL-mediated inhibition of I(K) in human 13-06-MG glioma cells. In OXAL-treated cells, TRAM-34 did not suppress I(K) amplitude in these cells. The intermediate-conductance Ca(2+)-activated K+ (IK(Ca)) channels subject to activation by DCEBIO and to inhibition by TRAM-34 or clotrimazole were functionally expressed in these cells. Unlike cisplatin, OXAL decreased the probability of IK(Ca)-channel openings in a concentration-dependent manner with an IC50 value of 67 µM. No significant change in single-channel conductance of IK(Ca) channels in the presence of OXAL was demonstrated. Neither large-conductance Ca(2+)-activated K+ channels nor inwardly rectifying K+ currents in these cells were affected in the presence of OXAL. OXAL also suppressed the proliferation and migration of 13-06-MG cells in a concentration- and time-dependent manner. OXAL reduced IK(Ca)-channel activity in LoVo colorectal cancer cells. Taken together, the inhibition by OXAL of IK(Ca) channels would conceivably be an important mechanism through which it acts on the functional activities of glioma cells occurring in vivo.

  4. Adrenergic activation of steroid 5alpha-reductase gene expression in rat C6 glioma cells: involvement of cyclic amp/protein kinase A-mediated signaling pathway.

    PubMed

    Morita, Kyoji; Arimochi, Hideki; Tsuruo, Yoshihiro

    2004-01-01

    Steroid 5alpha-reductase (5alpha-R) is well known as the enzyme converting progesterone and other steroid hormones to their 5alpha-reduced metabolites and has been reported to be localized in both neuronal and glial cells in the brain. Previously, the enzyme activity in glial cells has been shown to be enhanced either by coculturing with neuronal cells or by adding the conditioned medium of neuronal cells, suggesting a possible implication of neuro-glial interactions in the regulation of neurosteroid metabolism in the brain. In the present studies, the effects of adrenergic agonists on 5alpha-R mRNA and protein levels in rat C6 glioma cells were examined as one of the model experiments for investigating the influence of neuronal activity on the expression of 5alpha-R gene in the glial cell. The direct challenge of beta-adrenergic agonists to glioma cells resulted in the rapid and transient elevation of 5alpha-R mRNA levels through the activation of the cyclic AMP (cAMP)/protein kinase A-mediated signaling pathway. Further studies showed that cAMP-induced 5alpha-R mRNA expression was completely abolished by pretreatment of cells with actinomycin D and also indicated that the elevation of 5alpha-R mRNA levels was accompanied by an increase in enzyme protein in the cells. These findings provide strong evidence that the stimulation of beta-adrenergic receptors might induce the transcriptional activation of 5alpha-R gene expression in glial cells, proposing the possibility that neuronal activity might be involved in the production of neuroactive 5alpha-reduced steroids in the brain.

  5. Use of cardiac glycosides and risk of glioma.

    PubMed

    Seliger, Corinna; Meier, Christoph R; Jick, Susan S; Uhl, Martin; Bogdahn, Ulrich; Hau, Peter; Leitzmann, M F

    2016-04-01

    Cardiac glycosides induce apoptotic effects on glioma cells, but whether cardiac glycosides protect against risk for glioma is unknown. We therefore explored the relation between glycoside u