Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transduction of cancer cells with herpes simplex virus thymidine kinase gene (HSVtk) followed by prodrug ganciclovir (GCV) treatment has been shown to induce apoptosis. In this study, four murine tumors including B16F10 melanoma, NG4TL4 sarcoma, H6 hepatoma and 1MEA 7R.1 hepatoma were found to vary in sensitivity to this gene therapy strategy in vitro but, at effective doses of GCV, the HSVtk-transduced cells of all four tumors showed similar kinetics of early rise in p53 protein levels, then cell cycle S-/G2-phase arrest and finally signs of apoptosis. Immunoblot analyses revealed that Fas (CD95/APO-1), Fas ligand (FasL) and two downstream mediators, RIP and caspase-3, (CPP32, YAMA, Apopain) were increased in GCV-treated HSVtk-transduced tumor cells the cell cycle arrest and before apoptosis. Increased expression of FasL could also be observed in vivo in HSVtk-transduced tumors induced to regress by GCV treatment. Enzyme measurements using specific substrate showed that the caspase-3 activation followed kinetically the FasL expression. More than half of the HSVtk/GCV-induced cell death could be abrogated by addition to the cell culture medium of a specific antisense oligonucleotide to block FasL synthesis, a recombinant Fas/Fc chimeric protein to compete with Fas receptor for FasL binding, or cell-permeable specific tetrapeptide inhibitors of caspase-3 or caspase-8.
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PMID:Involvement of Fas (CD95/APO-1) and Fas ligand in apoptosis induced by ganciclovir treatment of tumor cells transduced with herpes simplex virus thymidine kinase. 1043 92

The development of genetically modified "whole" tumor cell vaccines for cancer therapy relies on the efficient transduction and expression of genes by vectors. In the present study, we have used a disabled infectious single cycle-herpes simplex virus 2 (DISC-HSV-2) vector constructed to express cytokine or marker genes upon infection. DISC-HSV-2 is able to infect a wide range of tumor cells and efficiently express the beta-galactosidase reporter gene, granulocyte-macrophage colony-stimulating factor (GM-CSF), or IL-2 genes. Gene expression occurred rapidly after infection of tumor cells, and the level of production of the gene product (beta-galactosidase, GM-CSF, or IL-2) was shown to be both time-and dose-dependent. Vaccination with irradiated DISC-mGM-CSF or DISC-hIL-2-infected murine tumor cells resulted in greatly enhanced immunity to tumor challenge with live parental tumor cells compared with control vaccines. When used therapeutically to treat existing tumors, vaccination with irradiated DISC-mGM-CSF-infected tumor cells significantly reduced the incidence and growth rates of tumors when administered locally adjacent to the tumor site, providing up to 90% protection. The prophylactic and therapeutic efficacy of DISC-mGM-CSF-infected cells was shown initially using a murine renal cell carcinoma model (RENCA), and the results were confirmed in two additional murine tumor models: the M3 melanoma and 302R sarcoma. Therapy with DISC-infected RENCA "whole" cell vaccines failed to reduce the incidence or growth of tumor in congenitally T-cell deficient (Nu+/Nu+) mice or mice depleted of CD4+ and/or CD8+ T-lymphocytes, confirming that both T-helper and T-cytotoxic effector arms of the immune response are required to promote tumor rejection. These preclinical results suggest that this "novel" DISC-HSV vector may prove to be efficacious in developing genetically modified whole-cell vaccines for clinical use.
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PMID:Preclinical evaluation of "whole" cell vaccines for prophylaxis and therapy using a disabled infectious single cycle-herpes simplex virus vector to transduce cytokine genes. 1074 37

The cellular oncoprotein Ewing's sarcoma oncogene (EWS)/activating transcription factor 1 (ATF1) is a highly specific marker for malignant melanoma of soft parts (MMSP) and is a potent activator of several cAMP-inducible promoters, including the somatostatin promoter. Here we explored the potential for using the somatostatin promoter to direct toxic gene expression in MMSP cells. When introduced into MMSP cells, a somatostatin-herpes simplex virus thymidine kinase fusion gene confers strong and cell-specific sensitivity to the cytotoxic prodrug ganciclovir. Ganciclovir sensitivity requires the ATF-binding site present in the somatostatin promoter, indicating that toxic gene expression is caused by EWS/ATF1. We also tested the efficacy of recombinant adenoviruses adenoviruses for gene delivery and expression in two MMSP cell lines (DTC1 and Su-ccs-1). Surprisingly, several promoters (including somatostatin) that are strongly activated by EWS/ATF1 in transient assays are not activated in DTC1 and Su-ccs-1 cells when present in an adenovirus vector. In summary, our findings demonstrate the potential for using the somatostatin promoter for cytotoxic prodrug therapy for MMSP. However, first-generation adenovirus vectors cannot be used as promoter delivery vehicles for toxic gene expression in MMSP cells.
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PMID:The cellular oncogene EWS/activating transcription factor 1 is unable to activate adenovirus-borne promoters: implications for cytotoxic prodrug therapy of malignant melanoma of soft parts. 1076 45

A recombinant MVMp of the fibrotropic strain of minute virus of mice (MVMp) expressing the chloramphenicol acetyltransferase reporter gene was used to infect a series of biologically relevant cultured cells, normal or tumor-derived, including normal melanocytes versus melanoma cells, normal mammary epithelial cells versus breast adenocarcinoma cells, and normal neurons or astrocytes versus glioma cells. As a reference cell system we used normal human fibroblasts versus the SV40-transformed fibroblast cell line NB324K. After infection, we observed good expression of the reporter gene in the different tumor cell types, but only poor expression if any in the corresponding normal cells. We also constructed a recombinant MVMp expressing the green fluorescent protein reporter gene and assessed by flow cytometry the efficiency of gene transduction into the different target cells. At a multiplicity of infection of 30, we observed substantial transduction of the gene into most of the tumor cell types tested, but only marginal transduction into normal cells under the same experimental conditions. Finally, we demonstrated that a recombinant MVMp expressing the herpes simplex virus thymidine kinase gene can, in vitro, cause efficient killing of most tumor cell types in the presence of ganciclovir, whilst affecting normal proliferating cells only marginally if at all. However, in the same experimental condition, breast tumor cells appeared to be resistant to GCV-mediated cytotoxicity, possibly because these cells are not susceptible to the bystander effect. Our data suggest that MVMp-based vectors could prove useful as selective vehicles for anticancer gene therapy, particularly for in vivo delivery of cytotoxic effector genes into tumor cells.
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PMID:Tumor-selective gene transduction and cell killing with an oncotropic autonomous parvovirus-based vector. 1082 6

The large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) is a multifunctional protein that contains a serine-threonine protein kinase (PK) activity (Nelson, J. W., Zhu, J. , Smith, C. C., Kulka, M., and Aurelian, L. (1996) J. Biol. Chem. 271, 17021-17027). Phylogenetic analyses indicated that ICP10 PK belongs to a distinct subfamily of growth factor receptor serine-threonine PKs that are characterized by their ability to function with a limited number of conserved catalytic motifs (Hunter, J. C. R., Smith, C. C., and Aurelian, L. (1995) Int. J. Onc. 7, 515-522). Here, we report the isolation and characterization of a novel gene, designated H11, that contains an open reading frame of 588 nucleotides, which encodes a protein similar to ICP10 PK. The H11 protein has Mn(2+)-dependent serine-threonine-specific PK activity as determined with a GST-H11 fusion protein and by immununocomplex PK/immunoblotting assays of 293 cells transfected with a H11 eukaryotic expression vector. PK activity is ablated by mutation of Lys(113) within the presumtive catalytic motif II (invariant Lys). 293 cells stably transfected with H11 acquire anchorage-independent growth. Endogenous H11 RNA and the H11 phosphoprotein are expressed in melanoma cell lines and primary melanoma tissues at levels higher than in normal melanocytes and in benign nevi. Melanoma cell proliferation is inhibited by treatment with antisense oligonucleotides that inhibit H11 translation, suggesting that H11 expression is associated with cell growth.
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PMID:A novel human gene similar to the protein kinase (PK) coding domain of the large subunit of herpes simplex virus type 2 ribonucleotide reductase (ICP10) codes for a serine-threonine PK and is expressed in melanoma cells. 1083 16

To evaluate the potential of defective herpes simplex virus (HSV) amplicon vectors as in vivo cytokine gene transfer vehicles for active immunotherapy, we generated a defective HSV vector that encodes the murine granulocyte-macrophage colony-stimulating factor (GM-CSF) gene, using a replication-defective HSV as helper virus. A variety of murine tumor cell lines were efficiently infected in vitro with the defective GM-CSF vector (dvGM), and this led to the synthesis and secretion of murine GM-CSF. In an established bilateral subcutaneous tumor model with Harding-Passey murine melanoma, unilateral intratumoral inoculation of dvGM significantly inhibited tumor growth of both the inoculated and noninoculated contralateral tumors. This tumor inhibition was dose-dependent and resulted in increased survival of the dvGM-treated mice. Inoculation of a lacZ-expressing defective vector had no effect on tumor growth. We conclude that this defective HSV vector system offers an effective method for cytokine gene delivery in vivo and that GM-CSF expression in tumors has antitumor activity.
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PMID:Tumor growth inhibition by intratumoral inoculation of defective herpes simplex virus vectors expressing granulocyte-macrophage colony-stimulating factor. 1102 Mar 47

The class III POU gene brn-2, encoding the Brn-2/N-Oct-3 transcription factor, is widely expressed in the developing mammalian central nervous system. Brn-2 has also been found to regulate the melanocytic phenotype with N-Oct-3 DNA binding activity elevated in malignant melanoma, however, its mode of action is yet to be defined. The functional role of the Brn-2 transcription factor has been investigated through the analysis of protein-protein interactions it forms with a number of basal and melanocytic transcriptional regulatory proteins. In vivo interactions were tested by gene-cotransfection using the mammalian GAL4-Herpes Simplex viral protein 16 (VP16) two hybrid formation and direct protein binding by in vitro glutathione S-transferase (GST)-pull down assay. The Brn-2 protein was found to homodimerize in vivo with high affinity, using Brn-2 deletion constructs dimer complex formation was found to be dependent on the presence of both the homeodomain and linker regions of the POU-domain. However, the POU-homoedomain was dispensable for the formation of the dimerization interface in one of the partner molecules but not both, when the POU-linker region was removed the ability to interact was lost irrespective of the presence of the homeodomain. Dimerization of Brn-2/N-Oct-3 was also found to occur in DNA binding assays using melanoma cell line nuclear extracts and a recently reported dimer target sequence probe, which may have significant consequences for gene regulation in melanocytic tumours. Low affinity Brn-2 protein contacts have also been found with the basal transcription complex, including TATA binding protein (TBP) and the transcriptional coactivator p300, and with the Sox-10 and Pax-3 transcription factors that are known to play an important role in melanocyte cell formation.
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PMID:Domains of Brn-2 that mediate homodimerization and interaction with general and melanocytic transcription factors. 1102 84

Adenoviral transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene followed by administration of gancyclovir (GCV) was used to treat B 16 melanoma of C 57 BL/6 mice. B 16 murine melanoma cells transduced in vitro by a recombinant replication-defective adenovirus containing the HSV-tk gene [Ad(HSV-tk)] were highly sensitive to cell killing by GCV, and the IC50 was 0.1 microgram/ml. A significant "bystander effect" was observed when Ad(HSV-tk)-infected and -uninfected B 16 cells were mixed. Direct tumoral injection of Ad (HSV-tk) into established B 16 melanoma in C 57 BL/6 mice and subsequent treatment for 6 d with GCV resulted in the growth regression and necrosis of tumor nodules, and the tumor size was approximately reduced to one-twenty fifth of that of control animals. Finally, the safety of this treatment approach was demonstrated by limited dissemination of virus using sensitive RT-PCR. HSV-tk mRNA was detected only in the tumor nodule. These data indicated that gene therapy using Ad(HSV-tk)/GCV may function as an effective and safe alternative for treatment of melanoma in vivo.
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PMID:[Gene therapy using recombinant adenovirus carrying herpes simplex-thymidine kinase gene to treat mouse B 16 melanoma in vivo]. 1103 21

We have previously shown that avirulent but replication-competent herpes simplex virus (HSV) 1716 causes cell death in human melanoma cell lines in vitro and selectively replicates in melanoma tissue in nude mice. We now present a pilot study of intratumoral injection of HSV1716 into subcutaneous nodules of metastatic melanoma in five patients with stage 4 melanoma. Two patients each received one injection, two received two injections, and one received four injections of 10(3) plaque-forming units HSV1716. In one patient, flattening of previously palpable tumour nodules was seen 21 days after two direct injections of HSV1716, and in injected nodules from all three patients who received two or more injections there was microscopic evidence of tumour necrosis. Immunohistochemical staining of injected nodules revealed evidence of virus replication confined to tumour cells. These findings suggest that HSV1716 is non-toxic and could be of therapeutic benefit in patients with metastatic melanoma.
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PMID:Intralesional injection of herpes simplex virus 1716 in metastatic melanoma. 1122 73

Oncolytic herpes simplex virus type 1 (HSV-1) vectors are promising therapeutic agents for cancer. Their efficacy depends on the extent of both intratumoral viral replication and induction of a host antitumor immune response. To enhance these properties while employing ample safeguards, two conditionally replicating HSV-1 vectors, termed G47Delta and R47Delta, have been constructed by deleting the alpha47 gene and the promoter region of US11 from gamma34.5-deficient HSV-1 vectors, G207 and R3616, respectively. Because the alpha47 gene product is responsible for inhibiting the transporter associated with antigen presentation (TAP), its absence led to increased MHC class I expression in infected human cells. Moreover, some G47Delta-infected human melanoma cells exhibited enhanced stimulation of matched antitumor T cell activity. The deletion also places the late US11 gene under control of the immediate-early alpha47 promoter, which suppresses the reduced growth properties of gamma34.5-deficient mutants. G47Delta and R47Delta showed enhanced viral growth in a variety of cell lines, leading to higher virus yields and enhanced cytopathic effect in tumor cells. G47Delta was significantly more efficacious in vivo than its parent G207 at inhibiting tumor growth in both immune-competent and immune-deficient animal models. Yet, when inoculated into the brains of HSV-1-sensitive A/J mice at 2 x 10(6) plaque forming units, G47Delta was as safe as G207. These results suggest that G47Delta may have enhanced antitumor activity in humans.
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PMID:Oncolytic herpes simplex virus vector with enhanced MHC class I presentation and tumor cell killing. 1135 31


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