Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cationic liposomes containing the human interferon-beta (IFN-beta) gene induce marked growth inhibition in human glioma cells. In vivo experiments using an human glioma implanted into the brains of nude mice have demonstrated a definite growth-inhibitory effect, achieving complete tumor regression with multiple intratumoral injections of the gene. However, nude mouse studies are inadequate to evaluate antitumor effects fully, especially those related to activation of the host immune response. This article aimed to investigate antitumor effects and immune response activation by murine IFN-beta gene transfer in syngeneic mice. In vitro experiments demonstrated a stronger growth-inhibitory effect of liposomes containing the murine IFN-beta gene on a GL261 mouse glioma cell line than exogenously added murine IFN-beta. In in vivo experiments, intratumoral administration of liposomes containing the murine IFN-beta gene resulted in a 16-fold reduction in the mean volume of residual gliomas in the brains of C57BL/6 mice and massive infiltration of cytotoxic T lymphocytes (CTL) within the residual tumor, while few CTL were infiltrated in controls including murine IFN-beta, empty liposomes, naked plasmid expressing murine IFN-beta, and liposomes containing beta-galactosidase gene. In addition, 40% of mice treated with liposomes containing the murine IFN-beta gene were completely cured. These findings indicated that activation of cellular immunity participates in antitumor effects in vivo together with direct effects of the IFN-beta gene.
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PMID:Antitumor effect and cellular immunity activation by murine interferon-beta gene transfer against intracerebral glioma in mouse. 1049 Jul 73

Despite the development of numerous vectors for gene transfection to gliomas, patient survival length remains unaffected in clinical trials. For glioma gene therapy to be successful, the extent of gene transfer to the solid tumor tissue has to be high. In the present work we review some of the vector types and strategies so far utilized in experimental and clinical glioma gene therapy. Since gene transfer efficacy into solid glioma tissue is unknown for many vectors, we studied the gene transfer efficacy into multicellular spheroids derived from a human glioma cell line GaMg as well as into spheroids derived from human glioma biopsies (glioblastoma multiforme, GBM). A replication deficient retroviral vector from the Liz 9 packaging cell line was used for transfer of the bacterial beta-galactosidase lacZ gene into the target tissue. Gene transfer was obtained by adding medium containing virus from the producer cells to the target tissue. The experiments were also conducted with EGF (epidermal growth factor) added to the medium. The data show that the transfection rate ranged from 0-4.5% where the transfection efficacy was higher in spheroids after the addition of EGF. Most of the transfected cells were found at the surface, but transfected cells could also be observed in the center of the spheroids. We conclude that using this vector system, the transfection efficacy was low, even if the number of replicating cells was increased by adding EGF. The findings are consistent, and may partly explain, the lack of effect using this vector system during in vivo studies.
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PMID:Retroviral transfection of the lacZ gene from Liz-9 packaging cells to glioma spheroids. 1057 26

Gene therapy is a potent method to counteract neurodegeneration by introducing genetic information encoding neuroprotective factors. In this study cationic lipids were used to transfer DNA into C6 glioma cells and primary glial cells. When comparing the novel compound FuGene with other commercially-available lipids, it was found that FuGene markedly enhanced gene transfer of a beta-galactosidase reporter plasmid into C6 glioma cells. FuGene had several advantages compared to other lipids, such as a very low toxicity and the capability of transfection under serum conditions. When optimizing, a DNA-lipid ratio of 150 ng DNA/1 microl FuGene and a concentration of 3 microl FuGene/1 ml medium was found to be optimal. The incubation time peaked after 8 h and the expression time reached an optimum between 2 and 6 days. When cells were transfected on 3 consecutive days for 6 h each ('boosting'), the transfection efficiency was markedly enhanced in primary glial cells. When using endotoxin-free DNA the transfection efficiency could be enhanced up to 3 times. The optimal transfection efficiency in C6 glioma cells and in primary glial cells was found to be 16.3 +/- 0.3% and 5.1 +/- 0.37% of total cells, respectively. In conclusion this study shows that the novel compound FuGene has a very high potential to transfer DNA into cells of glial origin, and it might be an interesting canditate for ex vivo and in vivo gene therapeutic approaches.
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PMID:Improved lipid-mediated gene transfer in C6 glioma cells and primary glial cells using FuGene. 1059 12

Recombinant adenovirus (Ad) vectors provide a means of local, therapeutic gene delivery to a wide range of neoplasms. Ad-mediated gene therapy trials in malignant glioma models have been limited by the need for high viral titers and multiple dosages. In an attempt to improve Ad vector gene transfer, we studied human (U87, D54) and rodent (GL261, C6) malignant glioma cell lines transfected with various doses of unmodified Ad vectors (AdZ), Ad vectors that contain an alteration of the fiber-coat protein and that direct virus binding to heparan sulfate receptors (AdZ.F(pK7)), and Ad vectors with modifications of the fiber-coat protein that direct virus binding to alpha1, integrin cellular receptors (AdZ.F(RGD)). AdZ.F(pK7) increased the frequency of cells expressing the reporter gene, beta-galactosidase, and improved transduction by 2- to 20-fold compared with AdZ in U87, D54, and GL261 cells. In U87, D54, GL261, and C6 tumors, AdZ.F(pK7) increased gene transfer by 10- to 100-fold compared with AdZ. AdZ.F(RGD) increased gene expression in C6 xenografts compared with AdZ, but had reduced transduction compared with the C6 xenografts of AdZ in all other glioma tumors. These findings suggest that the increased tropisms resulting from alterations of the Ad vector fiber-coat protein as in AdZ.F(pK7) and AdZ.F(RGD) offer a feasible approach to improving in vitro and in vivo transduction efficiencies in certain malignant glioma cell lines.
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PMID:Modifications of the fiber in adenovirus vectors increase tropism for malignant glioma models. 1067 51

For glioma- and glioblastoma-specific gene expression, we utilized a nestin regulatory element whose activity was evaluated by the reporter gene lacZ. Nestin is a 38-kDa intermediate filament protein, and is expressed specifically in the neuroepithelial stem cells. Nestin is detected in gliomas and glioblastomas, but not in normal brain tissue. We constructed a nestin gene regulator by placing nestin's second intron before the 5' upstream region (2iNP). To obtain enhanced expression of this tissue-specific regulator, we utilized the adenovirus double-infection method with a Cre-loxP on/off switching system. We constructed a 'regulator' vector, Ax2iNPNCre, which expresses Cre recombinase under the control of the nestin regulatory element, 2iNP. A 'reporter' vector, AxCALNLNZK, expresses lacZ under the control of a strong CAG promoter when the stuffer sequence has been removed by Cre recombinase at a pair of loxP sites. We used seven human glioma/glioblastoma cell lines: U251, KG-1C, NGM5, U87 MG, LN-Z308, NP-2 and T98G. Of these, nestin was expressed highly in U251 and KG-1C, less in NGM5, and undetectably in the other four lines. With the use of the two adenovirus vectors, we found X-gal staining and high nestin regulator-promoted beta-galactosidase activities in four of the seven glioma/glioblastoma cell lines. Staining was strong in U251, KG-1C and NGM5, and less in U87 MG. LacZ expression was nearly undetectable in the non-glioma cell line, HeLa, but a little in COS-7. The adenovirus double-infection method, which uses a nestin regulator, is applicable for glioma/glioblastoma-specific expression.
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PMID:Glioma/glioblastoma-specific adenoviral gene expression using the nestin gene regulator. 1080 92

Experimental investigation of glioma biology and therapy requires a representative model and a convenient technique for regulating gene expression. We have established an in vivo model in which genetically modified rat C6 glioma cells (C6TL cells) are transplanted into nude mice brain, followed by specific transcriptional control of a transgene. Histologically, the tumors exhibit an astrocytic phenotype and closely resemble human malignant gliomas including diffuse brain invasion. Due to a stably integrated lacZ gene, individual tumor cells can be unequivocally identified in tissue sections by histochemistry for beta-galactosidase. Since C6TL cells carry the tet transactivator (tTA) gene, any additional gene under control of a tetracycline/tTA-responsive promoter can be transcriptionally regulated by the concentration of tetracycline. C6TL cells stably transfected with a tetracycline/tTA-responsive luciferase reporter gene showed 23-fold regulation of luciferase activity in vitro. After intracerebral transplantation a regulation of 4.5- to 8.3-fold was obtained, dependent on the concentration and the type of tetracycline in the drinking water. This model should be useful for studying the functional role of candidate genes in tumor biology as well as for experimental gene therapy studies.
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PMID:In vivo glioma model enabling regulated gene expression. 1086 92

Gene transfer into cells of CNS origin is an important tool to counteract neurodegeneration by introducing, e.g., neuroprotective molecules. Although viral gene transfer reveals the highest gene transfer efficiency, liposome-mediated gene transfer seems to become an attractive alternative. In this study we investigated the lipid-mediated gene transfer into primary neurons in vitro by using the novel nonliposomal lipid FuGene and compared it to primary glia and malignant C6 glioma cells. FuGene-mediated gene transfer was useful to transfer the reporter gene beta-galactosidase into C6 glioma cells, primary glia, and primary neurons. Lipofection was highly dependent on the surface bottom and did not result in good efficiencies when using glass compared to plastic dishes. Comparing to a standard lipofection (1 x 8 h), lipofection on 3 consecutive days for 6 h each ("boosting") markedly increased the gene transfer efficiency in primary glia (up to sevenfold) and in primary neurons (up to sixfold). The use of endotoxin-free DNA only slightly increased the transfection efficiency. Immunohistochemistry demonstrated MAP-2-positive neurons (up to 1614 neurons/16-mm well; 2.4% of total neurons) as well as TH-positive neurons (up to 48 neurons/16-mm well; 12.7% of TH neurons) expressing beta-galactosidase. We conclude that FuGene-mediated gene transfer is an attractive alternative to introduce genes of interest into cells of glial and neuronal origin; however, this technique lacks sufficient gene transfer efficiency.
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PMID:Lipid-mediated gene transfer into primary neurons using FuGene: comparison to C6 glioma cells and primary glia. 1087 13

Recombinant adenoviruses are highly advantageous as vectors for transferring genes into mammalian cells, but the transfer is not efficient in all types of cells. We investigated the effects of four adenoviral receptors [integrinalphav, integrinbeta3, integrinbeta5, and human coxsackievirus and adenovirus receptor (hCAR)] on adenovirus-mediated transfer of exogenous cDNA into each of 10 glioma cell lines. Transfection efficiency varied widely from one cell line to another (0-100%) when we measured it by infection with AdLacZ, a vector designed to express beta-galactosidase. Levels of integrinalphav and integrinbeta5 expression were similar among the 10 cell lines, but expression of hCAR and integrinbeta3 varied significantly. As these observations indicated a possible correlation between expression of hCAR and the efficiency of gene transfer, we induced the hCAR gene into three glioma cell lines (T98G, U118MG, and U138MG) that expressed hCAR at very low levels and had also revealed low efficiencies of adenoviral gene transfer. In U118MG- and U138MG-derived cells that had regained the ability to express hCAR in stable fashion, adenovirus-mediated gene transfer became highly efficient. Moreover, addition of the peptide corresponding to the extracellular domain of hCAR (ECD-hCAR) by preincubation significantly increased the adenovirus infectivity to these adenovirus-tolerant cells. These results suggest that hCAR could be one of important determinants of the infectivity of adenovirus, and that the ECD-hCAR might be a novel useful tool for improvement of adenovirus-mediated gene therapy against the adenovirus-tolerant cancer cells.
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PMID:Significant increase of adenovirus infectivity in glioma cell lines by extracellular domain of hCAR. 1090 63

We used particle-mediated gene transfer by a custom-built gene gun to transfect two well-established human glioma (D54MG and U251) and melanoma (SK mel 28 and Ed 141) cell lines, as well as two glioma lines locally established from primary patient tumors (Ed 147 and Ed 149). Using beta-galactosidase as a reporter gene, D54MG, U251, Ed 141 and SK mel 28 showed an average transfection efficiency of 15-40%, whereas Ed 147 and Ed 149 had mean transfection efficiencies of 3% and 5% respectively. Twenty-four hours after transfection with the gene encoding human interleukin-12 (IL-12), ELISA was performed on cell supernatants (mean of n = 12 for each cell line). IL-12 expression was extremely variable between the different cell lines, ranging from 52 to 1,151 pg/10(6) cells/24 h. Results were very similar when cells were exposed to 20,000 rads of gamma irradiation 2 h after transfection. When the cell lines were transfected with human granulocyte-macrophage colony-stimulating factor, 24 h levels were: 13.0 (Ed 147), 17.8 (Ed 149), 18.6 (Ed 141), 27.4 (D54MG) and 27.7 ng/10(6) cells/24h (U251). SK mel 28 produced 88.1 ng/10(6) cells/24 h. We conclude that the gene gun can efficiently transfect a variety of immortalized, well-established and locally-established glioma and melanoma cell lines. High dose gamma irradiation does not adversely affect the expression of the foreign gene (IL-12) at 24 h. Significantly, transfected cell lines show different levels of expression depending on the particular gene/plasmid introduced. Therefore, each cell line has to be assessed individually for the level of expression of each introduced gene.
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PMID:Gene gun transfection of human glioma and melanoma cell lines with genes encoding human IL-12 and GM-CSF. 1093 96

The genes encoding the cyclin-dependent kinase inhibitors p16INK4A (CDKN2A) and p15INK4B (CDKN2B) are frequently homozygously deleted in a variety of tumor cell lines and primary tumors, including glioblastomas in which 40-50% of primary tumors display homozygous deletions of these two loci. Although the role of p16 as a tumor suppressor has been well documented, it has remained less well studied whether p15 plays a similar growth-suppressing role. Here, we have used replication-defective recombinant adenoviruses to compare the effects of expressing wild-type p16 and p15 in glioma cell lines. After infection, high levels of p16 and p15 were observed in two human glioma cell lines (U251 MG and U373 MG). Both inhibitors were found in complex with CDK4 and CDK6. Expression of p16 and p15 had indistinguishable effects on U251 MG, which has homozygous deletion of CDKN2A and CDKN2B, but a wild-type retinoblastoma (RB) gene. Cells were growth-arrested, showed no increased apoptosis, and displayed a markedly altered cellular morphology and repression of telomerase activity. Transduced cells became enlarged and flattened and expressed senescence-associated beta-galactosidase, thus fulfilling criteria for replicative senescence. In contrast, the growth and morphology of U373 MG, which expresses p16 and p15 endogenously, but undetectable levels of RB protein, were not affected by exogenous overexpression of either inhibitor. Thus, we conclude that overexpression of p15 has a similar ability to inhibit cell proliferation, to cause replicative senescence, and to inhibit telomerase activity as p16 in glioma cells with an intact RB protein pathway.
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PMID:Adenovirus-mediated overexpression of p15INK4B inhibits human glioma cell growth, induces replicative senescence, and inhibits telomerase activity similarly to p16INK4A. 1093 91


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