Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study, human monocytes/macrophages were observed to kill human U251 glioma cells expressing membrane macrophage colony-stimulating factor (mM-CSF) via a swelling and vacuolization process called paraptosis. Human monocytes responded to the mM-CSF-transduced U251 glioma cells, but not to viral vector control U251 glioma cells (U251-VV), by producing a respiratory burst within 20 min. Using patch clamp techniques, functional big potassium (BK) channels were observed on the membrane of the U251 glioma cell. It has been previously reported that oxygen indirectly regulates BK channel function. In this study, it was demonstrated that prolonged BK channel activation in response to the respiratory burst induced by monocytes initiates paraptosis in selected glioma cells. Forced BK channel opening within the glioma cells by BK channel activators (phloretin or pimaric acid) induced U251 glioma cell swelling and vacuolization occurred within 30 min. U251 glioma cell cytotoxicity, induced by using BK channel activators, required between 8 and 12 h. Swelling and vacuolization induced by phloretin and pimaric acid was prevented by iberiotoxin, a specific BK channel inhibitor. Confocal fluorescence microscopy demonstrated BK channels co-localized with the endoplasmic reticulum and mitochondria, the two targeted organelles affected in paraptosis. Iberiotoxin prevented monocytes from producing death in mM-CSF-expressing U251glioma cells in a 24 h assay. This study demonstrates a novel mechanism whereby monocytes can induce paraptosis via the disruption of internal potassium ion homeostasis.
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PMID:Human monocytes kill M-CSF-expressing glioma cells by BK channel activation. 1731 94

The response of human peripheral blood mononuclear cells (PBMC) to cloned human HLA-A2+ U251 glioma cells (U251-2F11/TK) expressing membrane macrophage colony stimulating factor (mM-CSF) was investigated in vitro and in vivo. Enriched human monocytes derived from cancer patients produced a respiratory burst following 20min of interaction with mM-CSF expressing U251 glioma cells. This respiratory burst response was not observed in the enriched human monocytes following similar exposure to the viral vector control U251 (U251-VV) cells. Reactive oxygen species such as H(2)O(2) and HOCl produced death of the U251 cells. The U251-2F11/TK cells failed to grow in severely compromised combined immunodeficient (NIH-bg-nu-xidBR) mice that were depleted of murine monocyte/macrophages then reconstituted with human HLA-A2+ PBMC. Reactive oxygen species (ROS) were produced by PBMC, both in vitro and in vivo in response tomM-CSF expressing U251 cells. U251-2F11/TK cells failed to form subcutaneous tumors in macrophage depleted mice reconstituted with human PBMC; whereas, progressive growth of such tumors was observed with the U251-VV cells. U251-2F11/TK tumors formed if the initial inoculums of PBMC were depleted of monocytes. From this work it can be concluded that mM-CSF transduced U251-2F11/TK glioma cells can safely stimulate human innate immune responses in vivo.
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PMID:Generation of human innate immune responses towards membrane macrophage colony stimulating factor (mM-CSF) expressing U251 glioma cells within immunodeficient (NIH-nu/beige/xid) mice. 1768 58

Macrophage colony stimulating factor (M-CSF) is a cytokine which has been recently reported to have a neuroprotective effect on ischemic rat brain. In this study, we investigated the effect of chotosan, an oriental medicine, which has been clinically demonstrated to be effective for the treatment of vascular dementia, on M-CSF gene expression in rats with permanent occlusion of bilateral common carotid arteries (P2VO) in vivo and in a C6Bu-1 glioma cell line in vitro. The expression level of M-CSF mRNA in the cerebral cortices of P2VO rats was significantly higher than that in the cerebral cortices of sham-operated animals. Repeated treatment of P2VO rats with chotosan (75 mg/kg per day) for 4 d after P2VO significantly increased the expression level of M-CSF mRNA in the cortex but it had no effect on the expression of beta-actin, granulocyte colony stimulating factor (G-CSF), granulocyte/macrophage colony stimulating factor (GM-CSF) mRNAs. Moreover, the present in vitro studies revealed that chotosan treatment (10-100 mug/ml) of C6Bu-1 glioma cells dose-dependently enhanced M-CSF mRNA expression without affecting the expression of G-CSF, GM-CSF, and inducible nitric oxide synthase mRNAs. The effect of chotosan was reversed by Ro 31-8220 (1 muM), a selective protein kinase C (PKC) inhibitor, but not by H-89 (10 muM), a selective protein kinase A (PKA) inhibitor. These findings suggest that the upregulatory effect of chotosan on M-CSF mRNA expression involves PKC and may play an important role in the anti-vascular dementia action of this formula.
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PMID:Chotosan enhances macrophage colony-stimulating factor mRNA expression in the ischemic rat brain and C6Bu-1 glioma cells. 1805 7

Clinical and immunological analysis of the efficiency of combined immunotherapy with the use dendritic cells for the treatment of malignant glioma of the brain was carried out. Dendritic cells generated in the presence of granulocyte-macrophage CSF and IFN-alpha retain their functional characteristics in patients with gliomas, which suggests the possibility of their use for the treatment of malignant tumors (glioma) of the brain. Combined therapy using interferon-induced dendritic cells was associated with generation of antigen-specific immune response during vaccinations. The results indicate satisfactory tolerance of combined immunotherapy using dendritic cells and the absence of toxic side effects at the stage of adoptive immunotherapy and at the stage of vaccinations with dendritic cells. Clinical trials showed that vaccinations with dendritic cells included into combined immunotherapy improved the quality of life and survival of patients with malignant gliomas.
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PMID:Use of interferon-alpha-induced dendritic cells in the therapy of patients with malignant brain gliomas. 1821 16

Inflammatory pseudotumors (IPs) arising in the CNS (IP-CNS) are quite rare. We report here a case of IP in a 5-year-old boy. Intraoperatively there was a well-defined extra-axial lesion in the right frontobasal region with CSF all around. There was no dural attachment. The tumor was removed piece-meal. On pathological examination, the lesion was well circumscribed and comprised of spindled cells in a collagenous background with sprinkling of inflammatory cells. The case was worked up considering the possibilities of low grade glioma, lymphoplasmacyte-rich meningioma, fungal/tubercular infection or inflammatory pseudotumors. Appropriate immunohistochemical stains were performed to rule out the rare possibility of lymphoma or plasmacytoma. The spindled cells were diffusely immunopositive for vimentin and only occasional cells were positive for smooth muscle actin (SMA). The cells did not show anaplastic lymphoma kinase-1 immunopositivity. Based on the above morphological and immunohistochemical analysis, a diagnosis of inflammatory pseudotumor was rendered.
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PMID:Intracranial inflammatory pseudotumor: report of a rare case. 1828 68

Within tumours, many non-neoplastic cells such as fibroblasts, endothelial cells, and macrophages assist tumour growth by producing various growth factors and pro-angiogenic cytokines. Various tumour-derived molecules drive tumour-associated macrophages towards an anti-inflammatory phenotype (M2) and thus promoting tumour growth. Here we investigated microglia/macrophage differentiation in glioma tissues by means of immunostaining of paraffin-embedded glioma samples. The number of microglia/macrophages with positive staining for CD163 and CD204, which are believed to be markers for M2 macrophages, was correlated with the histological grade of the gliomas. The ratio of M2 macrophages in the tumour-associated microglia/macrophages was also associated with the histological grade. Culture supernatant from the glioma cell line can stimulate macrophages to develop into the M2 phenotype in vitro. Macrophage colony-stimulating factor (M-CSF), which strongly induces M2 polarization of macrophages, was significantly correlated with histological malignancy and with the proportion of M2 microglia/macrophages in vivo. In addition, the proportion of M2 microglia/macrophages and M-CSF expression in tumour cells correlated well with proliferation of glioblastoma cells. These results suggest that tumour-derived M-CSF induces a shift of microglia/macrophages towards the M2 phenotype, which influences tumour growth. Evaluation of the proportion of M2 microglia/macrophages and M-CSF expression in tumour tissue would be useful for assessment of microglia/macrophage proliferative activity and the prognosis of patients with gliomas.
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PMID:Possible involvement of the M2 anti-inflammatory macrophage phenotype in growth of human gliomas. 1855 15

Dendritic cells (DC) are specialized cells that capture and present antigen to T cells. Recent advances have been made in understanding their origin, heterogeneity, and the signals that induce their migration and maturation resident microglia are antigen-presenting cells (APC) involved in stimulation or reactivation of CNS-targeted T cells. Generation of DC from microglia, as demonstrated ex vivo, may support GM-CSF-driven differentiation of brain DC from local, likely, microglial progenitors. Here, we report the establishment of long-term cultures of rat ecto-mesenchymal stem cells (EMSCs) using specific supplemented media for induction. These EMSCs share some morphological characteristics and the allostimulatory capacity of classical DCs, and when transplanted into the brain using a rat glioma model survive within the cortex, and are morphologically and phenotypically similar to microglia over 7 days. Our findings related to the development and differentiation of microglial progenitors support the view that microglia are derived prenatally from mesodermal progenitors that are distinct from monocytes.
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PMID:Development of rat antigen-presenting cells from pluripotent ecto-mesenchymal stem cells in vitro and in vivo. 1861 68

Leptomeningeal (LM) dissemination arises rarely in patients with low-grade gliomas. Few cases of LM dissemination of spinal cord low-grade gliomas have been reported in children. Here, we report a case of an intramedullary spinal cord low-grade glioma occurring in an adult presenting by LM dissemination. A 57-year-old man presented with a history of headaches and visual acuity deterioration. Neurological examination revealed mental confusion, decreasing left limb strength and left positive Babinski sign. Lumbar puncture showed low CSF glucose, high CSF protein and no tumor cells. Spinal MRI revealed an intramedullary spinal lesion with a diffuse leptomeningeal enhancement. A spinal meningeal biopsy showed arachnoiditis with isolated atypical cells which were cytokeratin immunopositive. A differential diagnosis was proposed between arachnoiditis close to an infectious process or close to meningeal carcinomatosis. An intramedullary biopsy was programmed but the patient died 1 month after biopsy. The post-mortem examination showed thickened leptomeninges and an ill-circumscribed intramedullary grey lesion. Histological examination revealed a low-grade glial neoplasm composed of monomorphous spindle "piloid" cells with diffuse dissemination to leptomeninges. Glial fibrillary acidic protein immunostaining showed scattered immunoreactive cells. Clinical and pathological features of this case are unusual. Pathogenesis and prognosis of low-grade gliomas with LM dissemination are poorly understood. This case, like cases occurring in children, cannot easily be classified in the present WHO system of classification of CNS tumors. Spinal low-grade gliomas with LM dissemination may represent a possible distinctive clinico-pathological entity.
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PMID:Leptomeningeal dissemination of low-grade intramedullary gliomas: about one case and review. 1912 71

In an attempt to develop effective vaccines against central nervous system (CNS) tumors, we evaluated the ability of vaccines with standard dendritic cells (DC) versus type 1 polarizing DCs (DC1) to induce glioma-specific type 1 CTLs with CNS tumor-relevant homing properties and the mechanism of their action. C57BL/6 mouse-derived bone marrow cells were cultured with mouse granulocyte/macrophage colony-stimulating factor (GM-CSF) for 6 days, and CD11c(+) cells were subsequently cultured with GM-CSF, rmIFN-gamma, rmIFN-alpha, rmIL-4, and polyinosinic-polycytidylic acid stabilized by lysine and carboxymethylcellulose for 24 hours to generate DC1s. In analogy to their human counterparts, mouse DC1s exhibited surface marker profiles of mature DCs and produced high levels of IL-12 and CXCL10. Importantly for their application as cancer vaccines, such DC1s stably retained their type 1 phenotype even when exposed to type 2-promoting or regulatory T cell (Treg)-promoting environments. Consistently, mouse DC1s induced antigen-specific type 1 CTLs more efficiently than nonpolarized DCs in vitro. DC1s given s.c. migrated into draining lymph nodes, induced antigen-specific CTLs, and suppressed Treg accumulation. In addition, s.c. immunization with DC1s loaded with glioma-associated antigen (GAA)-derived CTL epitope peptides prolonged the survival of CNS GL261 glioma-bearing mice, which was associated with efficient CNS glioma homing of antigen-specific CTLs. Intratumoral injections of GAA peptide-loaded DC1s further enhanced the anti-CNS glioma effects of DC1-based s.c. immunization. Interestingly, the antitumor functions were abrogated with CXCL10(-/-) mouse-derived DC1s. Collectively, these findings show the anti-CNS glioma effects of DC1-based therapy and a novel role of CXCL10 in the immunologic and therapeutic activity of DC-based cancer vaccines.
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PMID:Effective immunotherapy against murine gliomas using type 1 polarizing dendritic cells--significant roles of CXCL10. 1919 Mar 35

Paraptosis is the programmed cell death pathway that leads to cellular necrosis. Previously, rodent and human monocytes/macrophages killed glioma cells bearing the membrane macrophage colony stimulating factor (mM-CSF) through paraptosis, but the molecular mechanism of this killing process was never identified. We have demonstrated that paraptosis of rat T9 glioma cells can be initiated through a large potassium channel (BK)-dependent process initiated by reactive oxygen species. Macrophage mediated cytotoxicity upon the mM-CSF expressing T9-C2 cells was not prevented by the addition of the caspase inhibitor, zVAD-fmk. By a combination of fluorescent confocal and electron microscopy, flow cytometry, electrophysiology, pharmacology, and genetic knock-down approaches, we demonstrated that these ion channels control cellular swelling and vacuolization of rat T9 glioma cells. Cell lysis is preceded by a depletion of intracellular ATP. Six-hour exposure to BK channel activation caused T9 cells to over express heat shock proteins (Hsp 60, 70, 90 and gp96). This same treatment forced HMGB1 translocation from the nuclear region to the periphery. These last molecules are "danger signals" that can stimulate immune responses. Similar inductions of mitochondrial swelling and increased Hsp70 and 90 expressions by BK channel activation were observed with the non-immunogenic F98 glioma cells. Rats injected with T9 cells which were killed by prolonged BK channel activation developed immunity against the T9 cells, while the injection of x-irradiated apoptotic T9 cells failed to produce the vaccinating effect. These results are the first to show that glioma cellular death induced by prolonged BK channel activation improves tumor immunogenicity; this treatment reproduces the vaccinating effects of mM-CSF transduced cells. Elucidation of strategies as described in this study may prove quite valuable in the development of clinical immunotherapy against cancer.
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PMID:Molecular mechanisms of paraptosis induction: implications for a non-genetically modified tumor vaccine. 1924 76


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