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)

Current gene therapy technology is limited by the paucity of methodology for determining the location and magnitude of therapeutic transgene expression in vivo. We describe and validate a paradigm for monitoring therapeutic transgene expression by noninvasive imaging of the herpes simplex virus type 1 thymidine kinase (HSV-1-tk) marker gene expression. To test proportional coexpression of therapeutic and marker genes, a model fusion gene comprising green fluorescent protein (gfp) and HSV-1-tk genes was generated (tkgfp gene) and assessed for the functional coexpression of the gene product, TKGFP fusion protein, in rat 9L gliosarcoma, RG2 glioma, and W256 carcinoma cells. Analysis of the TKGFP protein demonstrated that it can serve as a therapeutic gene by rendering tkgfp transduced cells sensitive to ganciclovir or as a screening marker useful for identifying transduced cells by fluorescence microscopy or fluorescence-activated cell sorting (FACS). TK and GFP activities in the TKGFP fusion protein were similar to corresponding wild-type proteins and accumulation of the HSV-1-tk-specific radiolabeled substrate, 2'-fluoro-2'-deoxy-1beta-D-arabinofuranosyl-5-iodo-uracil (FIAU), in stability transduced clones correlated with gfp-fluorescence intensity over a wide range of expression levels. The tkgfp fusion gene itself may be useful in developing novel cancer gene therapy approaches. Valuable information about the efficiency of gene transfer and expression could be obtained by non-invasive imaging of tkgfp expression with FIAU and clinical imaging devices (gamma camera, positron-emission tomography [PET], single photon emission computed tomography [SPECT]), and/or direct visualization of gfp expression in situ by fluorescence microscopy or endoscopy.
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PMID:Functional coexpression of HSV-1 thymidine kinase and green fluorescent protein: implications for noninvasive imaging of transgene expression. 1093 50

We have reported previously that s.c. immunization of rats with IL-4 transduced 9L gliosarcoma cells (9L-IL-4) induced a potent antitumor immunity against intracranial, parental 9L tumors. Subcutaneous implantation of 9L-IL-4 influenced the systemic humoral response, which was demonstrated by Th2-type isotype-switching and the induction of cellular immune responses, which played a critical role in the rejection of tumors. Serological analyses of recombinant cDNA expression libraries (SEREX), has recently emerged as a powerful method for serological identification of tumor-associated antigens (TAAs) and/or tumor rejection antigens (TRAs). Because IL-4 is known to activate B cells and to promote humoral responses, and inasmuch as induction of humoral responses by central nervous system tumors has been reported to be minimal, we investigated whether the induction of a potent humoral immune response against 9L TAAs or TRAs in rats immunized s.c. with 9L-IL4 could be demonstrated. Screening of 5 x 10(5) independent clones of 9L-expression cDNA library for the presence of reactive antibodies in the serum from a 91-IL-4 immunized rat led to the identification of three different TAAs. One 9L TAA (clone 29) was demonstrated to be calcyclin, a member of the S-100 family of calcium-binding proteins. The second 9L TAA (clone 37) was demonstrated to be the rat homologue of the J6B7 mouse immunomodulatory molecule. The third TAA (clones 158 and 171) was determined to be the rat homologue of the mouse Id-associated protein 1 (MIDA1), a DNA-binding, protein-associated protein. Northern blotting demonstrated that message for calcyclin was overexpressed in 9L cells. Message encoding MIDA1 was highly expressed in parental 9L cells and thymus and, to a lesser degree, in testis, suggesting that MIDA1 was comparable with the cancer/testis category of TAAs. Sera obtained from animals bearing 9L-IL-4 were found to have a higher a frequency and titer of antibodies to these antigens when compared with sera obtained from rats bearing sham-transduced 9L (9L-neo) cells. To determine whether immunization with these TAAs induced antitumor immunity, animals were immunized by intradermal injection with expression plasmids encoding calcyclin or MIDA1. Subsequent challenge of rats with parental 9L resulted in significant suppression of tumor growth in animals immunized with MIDA1, but not with calcyclin. These results indicate that MIDA1 is an effective 9L TRA and will be useful for the investigation of specific antitumor immunity in this glioma model. Furthermore, these results suggest that this approach, termed "cytokine-assisted SEREX (CAS)," may serve as an effective strategy for identification of TRAs for in animal-glioma models of cytokine gene therapy, and potentially in humans undergoing cytokine gene therapy protocols as well.
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PMID:Immunization with an antigen identified by cytokine tumor vaccine-assisted SEREX (CAS) suppressed growth of the rat 9L glioma in vivo. 1128 40

Decoy receptor 3 (DcR3) is a newly identified soluble protein that binds to CD95 ligand (CD95L) and inhibits its proapoptotic activity. Here we report that DcR3 is expressed by the majority of long-term and ex vivo malignant glioma cell lines as well as in human glioblastoma in vivo. Expression of DcR3 correlates with the grade of malignancy: 15 of 18 (83%) glioblastomas (WHO grade IV) but none of 11 diffuse astrocytomas (WHO grade II) exhibited DcR3 immunoreactivity. We also demonstrate that human malignant glioma cells engineered to release high amounts of DcR3 into the cell culture supernatant are protected from CD95L-induced apoptotic cell death. In contrast, DcR3 does not confer protection from the death ligand Apo2 ligand (TRAIL). Importantly, ectopic expression of DcR3 resulted in substantial differences in immune cell infiltration in the 9L rat gliosarcoma model. Thus, the infiltration of CD4+ and CD8+ T cells as well as microglia/macrophages into glioma was substantially decreased in DcR3-producing tumors compared with control tumors. Chemotaxis assays revealed that DcR3 counteracts the chemotactic activity of CD95L against microglial cells in vitro. These findings suggest that DcR3 may be involved in the progression and immune evasion of malignant gliomas.
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PMID:Soluble decoy receptor 3 is expressed by malignant gliomas and suppresses CD95 ligand-induced apoptosis and chemotaxis. 1128 59

Phage display techniques rely on nearly random oligonucleotide sequences inserted into the protein III filament binding protein of an Escherichia coli filamentous phage M13 to generate a library of phage that express more than 10(7) different peptides. Phage that expresses a sequence having high affinity for a specific molecule, cell, or tissue can then be isolated through selective binding and recovery. Selected phage cannot only be used as gene transfer vectors in themselves, but the small peptide epitopes can be sequenced and potentially recombined into the attachment proteins of viral vectors, or used by themselves to target other therapeutic agents and diagnostic imaging radiolabels. Most phage display selections are carried out against purified and/or fixed protein targets, raising concerns as to the relevance of the selected epitopes. We have selected phage from the CMTI library against viable U87-MG human malignant glioma cells using a derivation of biopanning. The library, which initially contained phage expressing 2x10(7) different epitope sequences, collapsed after four rounds of selection such that 42% of recovered clones expressed a consensus sequence. Selective binding to viable adherent U87-MG cells was subsequently demonstrated under physiologic conditions at 167% (+/-27%) unselected phage using a novel, viable enzyme-linked immunosorbent assay technique. In comparison, there was no difference in binding to control 9L rat gliosarcoma, PANC-1 human pancreatic adenocarcinoma, T98-MG human malignant glioma, or AST-4 human malignant glioma cells of selected compared to unselected phage. Using polymerase chain reaction, the epitope was recovered with flanking unique restriction sites for recombination into a herpes simplex virus type-1 vector. This study demonstrates and discusses optimized methodologies for using phage display to target viable cells.
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PMID:Isolation, characterization, and recovery of small peptide phage display epitopes selected against viable malignant glioma cells. 1149 72

Increased expression of gamma-glutamyltransferase (GGT) has been detected in a range of human malignancies and is thought to be involved in neoplastic proliferation and treatment resistance. Since GGT expression and its role in malignant glioma biology remain largely unknown, we investigated this phenomenon by immunostaining 26 higher-grade human astrocytic gliomas (WHO grades III and IV) with a monoclonal anti-GGT-antibody (138H11). Further, human pancreatic GGT cDNA was used for liposome-mediated transfection of 9L gliosarcoma cells. GGT-expressing and control 9L cells were cultured in media containing different amounts of essential amino acids and/or cytotoxic agents. Cell viability was evaluated by microplate MTT assay. Immunohistochemical staining of tumor specimens demonstrated that GGT expression is a frequent feature of higher-grade human astrocytic gliomas, but not of normal brain tissue. Human tumors were strongly GGT-positive in 6 of 7 cases of grade III astrocytoma, and in 12 of 19 grade IV astrocytoma (glioblastoma multiforme, GBM) cases. In the cell culture model, 9L-GGT cells had a growth advantage over control cells in cysteine-deficient medium. but not in standard or glutamine-free medium. No significant difference in numbers of viable cells of either clone was found in media containing the alkylating drug BCNU (5-200 microg/ml). In conclusion, GGT is expressed in a high percentage of human WHO grade III astrocytomas and GBM, but not in normal brain tissue. This molecule seems to give neoplastic cells a moderate growth advantage under in vivo conditions.
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PMID:Gamma-glutamyl transferase expression in higher-grade astrocytic glioma. 1150 14

Boron neutron capture therapy (BNCT) is dependent on the selective accumulation of boron-10 in tumor cells relative to the contiguous normal cells. Ion microscopy was used to evaluate the microdistribution of boron-10 from p-boronophenylalanine (BPA) in the 9L rat gliosarcoma and the F98 rat glioma brain tumor models. Four routes of BPA administration were used: i.p. injection, intracarotid (i.c.) injection [with and without blood-brain barrier disruption (BBB-D)], and continuous timed i.v. infusions. i.p. injection of BPA in the 9L gliosarcoma resulted in a tumor-to-brain (T:Br) boron-10 concentration ratio of 3.7:1 when measured at the tumor-normal brain interface. In the F98 glioma, i.c injection of BPA resulted in a T:Br ratio of 2.9:1, and this increased to 5.4:1 when BBB-D was performed. The increased tumor boron uptake would potentially enhance the therapeutic ratio of BNCT by >25%. At present, ion microscopy is the only technique to provide a direct measurement of the T:Br boron-10 concentration ratio for tumor cells infiltrating normal brain. In the 9L gliosarcoma, this ratio was 2.9:1 after i.p. administration. In the F98 glioma, i.c injection resulted in a ratio of 2.2:1, and this increased to 3.0:1 after BBB-D. Ion microscopy revealed a consistent pattern of boron-10 microdistribution for both rat brain tumor models. The boron-10 concentration in the main tumor mass (MTM) was approximately twice that of the infiltrating tumor cells. One hour after a 2-h i.v. infusion of BPA in rats with the 9L gliosarcoma, tumor boron-10 concentrations were 2.7 times higher than that of infiltrating tumor cells [83 +/- 23 microg/g tissue versus 31 +/- 12 microg/g tissue (mean +/- SD)]. Continuous 3- and 6-h i.v. infusions of BPA in the 9L gliosarcoma resulted in similar high boron-10 concentrations in the MTM. The boron-10 concentration in infiltrating tumor cells was two times lower than the MTM after a 3-h infusion. After 6 h, the boron-10 concentration in infiltrating tumor cells had increased nearly 90% relative to the 2- and 3-h infusions. A 24-h i.v. infusion resulted in similar boron-10 levels between the MTM and the infiltrating tumor cells. Boron concentrations in the normal brain were similar for all four infusion times (approximately 20 microg/g tissue). These results are important for BNCT, because clinical protocols using a 2-h infusion have been performed with the assumption that infiltrating tumor cells contain equivalent amounts of boron-10 as the MTM. The results reported here suggest that this is not the case and that a 6-h or longer infusion of BPA may be necessary to raise boron-10 levels in infiltrating tumor cells to that in the MTM.
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PMID:Quantitative imaging and microlocalization of boron-10 in brain tumors and infiltrating tumor cells by SIMS ion microscopy: relevance to neutron capture therapy. 1171 48

We evaluated the interaction between oncolytic, replication-competent adenoviral vectors and the herpes simplex virus-1 thymidine kinase (HSV1-tk) gene/ganciclovir (GCV) suicide system for the treatment of malignant gliomas. We constructed a panel of replication-competent adenoviral vectors in which the luciferase (IG.Ad5E1(+). E3Luc) or HSV1-tk gene (IG.Ad5E1(+).E3TK) replace the M(r) 19,000 glycoprotein (gp19K) coding sequence in the E3 region. IG.Ad5E1. IG.Ad5.ClipLuc and IG.AdApt.TK are E1-deleted viruses that contain the luciferase or the HSV1-tk gene in the former E1 region driven by the human cytomegalovirus promoter. IG.Ad5. Sarcoma 1800HSA.E3Luc contains an irrelevant gene in the E1 region, whereas the gp19K coding sequence in the E3 region is replaced by the luciferase gene as in the replicating virus IG.Ad5E1(+).E3Luc. For in vitro experiments, we used a panel of human glioma cell lines (U87 MG, T98G, A172, LW5, and U251), a rat gliosarcoma cell line (9 L), and human lung (A549) and prostate carcinoma (P3) cell lines. In vitro, GCV sensitivity (10 microg/ml) was studied in U87 MG cells after infection at a multiplicity of infection of 1 and 10. A s.c. U87 MG glioma xenograft model was established in NIH-bg-nu-xid mice. Tumors of 100-150 mm(3) were treated with a single injection of adenovirus 10(9) IU suspended in 100 microl of PBS, and GCV 100 mg/kg was administered i.p. twice daily for 7 days. The cytopathic effect of all three replication-competent adenoviral vectors was similar to the cytopathic effect of wild-type adenovirus 5 on all human cell lines tested, indicating that deletion of the E3 gp19K sequences did not affect the oncolytic effect of the vectors. In vitro, luciferase expression was the same for both E1-deleted vectors (IG.Ad5.ClipLuc and IG.Ad5. Sarcoma 1800HSA.E3Luc), demonstrating the strength of the internal E3 promoter even in the absence of E1A. However, in vitro expression levels obtained with replication-competent IG.Ad5E1(+). E3Luc were 3 log higher (allowing infection with a 2-3-log lower multiplicity of infection) in the human cell lines. In U87 MG glioma cells, the oncolytic effect of replication-competent IG.Ad5E1(+).E3TK was significantly enhanced by the addition of GCV and greatly exceeded the cytotoxicity of replication-incompetent IG.AdApt.TK combined with GCV. In established s.c. U87 MG glioma xenografts, a single injection of IG.Ad5E1(+).E3TK resulted in a significant slowing of tumor growth and prolonged survival compared with injection of IG.AdApt.TK. Addition of GCV slowed tumor growth, further adding to survival. In conclusion, the oncolytic effect of replicating adenoviral vectors and HSV1-tk/GCV have potent antitumor effects in gliomas. When combined, these two approaches are complementary, resulting in a significantly improved treatment outcome. In addition, replication-competent adenoviral vectors missing the E3 gp19K coding sequences, have oncolytic efficacy comparable with wild type. In combination with high expression levels obtained with the natural E3 promoter, such vectors are promising new anticancer agents.
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PMID:Treatment of malignant gliomas with a replicating adenoviral vector expressing herpes simplex virus-thymidine kinase. 1175 94

The injection of irradiated tumor cells genetically engineered to express the granolocyte macrophage-colony stimulating factor (GM-CSF) is reported as stimulating antitumoral immunity in several animal models. We used the 9L gliosarcoma rat model to investigate the potency of this strategy in relation to the central nervous system. After in vitro transduction experiments to generate 9L murine cells producing GM-CSF (9LmGM-CSF cells), we found that with the exception of one rat subcutaneously (s.c.) grafted with 108 9LmGM-CSF cells, syngenic rats s.c. injected (dorsal route) with 106-108 viable 9LmGM-CSF cells did not develop s.c. 9L gliosarcomas, while rats s.c. grafted with the same number of naive 9L cells died between 25 and 45 days postgraft. Intracerebral stereotactic injections of 4.104 naive 9L (without s.c. 9LmGM-CSF treatment) killed all the rats within 18-24 days, while s.c. grafting with 108 9LmGM-CSF cells wholly prevented the development of 9L brain gliosarcomas. These results outline the feasibility of the GM-CSF gene transfer approach in glioma (or at least gliosarcoma) gene therapy and could therefore serve as a basis for the development of an adjuvant treatment of glioblastomas using GM-CSF-producing tumor cell vaccines.
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PMID:Granulocyte macrophage-colony stimulating factor gene transfer to induce a protective anti-tumoral immune response against the 9L rat gliosarcoma model. 1195 7

Herpes simplex virus thymidine kinase (HSV-TK) and Escherichia coli cytosine deaminase (CD) are non-mammalian enzymes capable of converting innocuous prodrugs into cytotoxic metabolites. Both enzymes have been utilized independently, as well as together in 'suicide' gene therapy protocols to eliminate tumor cells in vitro and in vivo. We have used a set of replication defective HSV vectors expressing either or both enzymes to compare the efficacies of single and double suicide gene therapies in the 9L gliosarcoma model in vitro and in vivo. In cell culture experiments at high and low multiplicities of infection, combined expression of the two genes by vector TOCD/TK along with exposure to the matching prodrugs (ganciclovir and 5-fluorocytosine) showed increased cytotoxicity compared with exposure to either prodrug alone. However, the two gene combination was inferior to single gene treatments, suggesting that HSVtk and CD are mutually counteractive in the prodrug-dependent killing of glioma cells. In animal experiments, survival was not significantly prolonged by administration of both prodrugs to TOCD/TK-treated animals, while each single gene/prodrug pair resulted in increased survival. These results indicate that single suicide gene systems employing HSVtk or CD may be preferable over combinations of the two.
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PMID:Double suicide gene therapy using a replication defective herpes simplex virus vector reveals reciprocal interference in a malignant glioma model. 1197 34

As a means of enhancing immunity to gliomas, we investigated local delivery of rat, bone marrow-derived dendritic cells (DCs) into rat 9L gliosarcoma tumors and into 9L tumors induced to undergo apoptosis by gamma knife radiosurgery. Contrary to other tumors, local delivery of DCs had no therapeutic effect on 9L gliomas, even when tumor apoptosis was induced via radiosurgery, which leads to efficient "loading" of the DCs with tumor antigen. To determine whether antigen-presenting cells, such as DCs, were viable in tumors, we carried out multiparametric staining of 9L tumors, using phycoerythrin-conjugated OX6 (MHC class II) or OX62 (DC specific) and FITC-labeled Val-Ala-Asp-fluoromethyl ketone (FITC-VAD-FMK; activated caspases). It was determined that DCs were undergoing apoptosis in these tumors. We therefore sought to determine which glioma cell surface receptors or components of the extracellular matrix in gliomas influenced DC viability. Hyaluronan (HA) is a major component of glioma extracellular matrix and has been found to support tumor cell migration and metastasis. However, its influence on the immune system, and particularly on DCs, via its receptor CD44 is not well documented. Using reverse transcription-PCR, Northern blot, and Western blot analyses, we determined that HA stimulated production of inducible nitric oxide synthase (iNOS) in DCs. NO production by HA-stimulated DCs was then verified biochemically. NO production was dependent on the size of HA; intermediate HA fragments had the greatest capacity to induce NO production in DC, whereas completely digested HA oligosaccharides failed to induce NO. Furthermore, N-monomethyl-L-arginine, an inhibitor of iNOS, completely blocked HA-induced NO production by DCs. Because induction of NO results in the induction of apoptosis in macrophages as well as other cells, DCs treated with HA were examined for apoptosis in terminal deoxynucleotidyl transferase (TdT)-mediated dUTP biotin nick-end labeling assays. It was demonstrated that HA induced apoptosis in DCs and that induction of apoptosis was dependent on the production of NO because it was entirely inhibited by N-monomethyl-L-arginine. Using flow cytometric analyses with FITC-VAD-FMK, which is specific for activated caspases, we also determined that induction of apoptosis in DCs with HA could be titrated. Coincubation of 9L tumor cells with DCs was found to induce apoptosis in DCs as indicated by fluorescent staining with FITC-VAD-FMK. Specificity of this reaction for CD44-HA interactions was determined by pretreatment of DCs with anti-CD44 or pretreatment of 9L tumor cells with hyaluronidase, which blocked the induction of apoptosis in DCs. These data indicate that HA expressed by gliomas may contribute to their immunosuppressive effects by promoting apoptosis among professional antigen-presenting cells such as DCs via iNOS induction after CD44-HA interactions.
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PMID:Glioma-associated hyaluronan induces apoptosis in dendritic cells via inducible nitric oxide synthase: implications for the use of dendritic cells for therapy of gliomas. 1198 Jun 53


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