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)

The importance of CD8(+) cytolytic T cells for protection from viral infection and in the generation of immune responses against tumors has been well established. In contrast, the role of CD4(+) T-helper cells in human infection and in cancer immunity has yet to be clearly defined. In this pilot study, we show that immunization of three resected, high-risk metastatic melanoma patients with a T-helper epitope derived from the melanoma differentiation antigen, melanoma antigen recognized by T cells-1, results in CD4(+) T-cell immune responses. Immune reactivity to that epitope was detected by DR4-peptide tetramer staining, and enzyme-linked immunospot assay of fresh and restimulated CD4(+) T cells from patients over the course of the 12-month vaccine regimen. The postvaccine CD4(+) T cells exhibited a mixed T-helper 1/T-helper 2 phenotype, proliferated in response to the antigen and promiscuously recognized the peptide epitope bound to different human leukocyte antigen-DRbeta alleles. For 1 DRbeta1*0401(+) patient, antigen-specific CD4(+) T cells recognized human leukocyte antigen-matched antigen-expressing tumor cells, secreted granzyme B, and also exhibited cytolysis that was MHC class II-restricted. These data establish the immunogenicity of a class II epitope derived from a melanoma-associated antigen and support the inclusion of class II peptides in future melanoma vaccine therapies.
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PMID:Immune responses to a class II helper peptide epitope in patients with stage III/IV resected melanoma. 1529 1

Based on the observation that viral infection results in the presentation of virus-specific peptides in association with both MHC Class I and MHC Class II on the surface of infected cells, strategies have been designed to use recombinant viruses carrying tumour-associated antigen (TAA) genes as immunization vehicles to elicit tumour-specific immune responses. I report here on results from phase I clinical studies based on a canarypox viral vector system expressing TAAs of interest. Clinical studies conducted in patients with colorectal cancer to evaluate ALVAC-CEA, ALVAC-KSA, or ALVAC-p53 candidate vaccines have shown that this approach is safe and can induce tumour-specific responses. Additional clinical studies evaluating candidate vaccines against melanoma, targeting either the gp100, Mage 1 or Mage 3 molecules are in progress. On the basis of our results and in the context of parallel studies being conducted with other viral systems, the characteristics of an ideal viral vector system, as it applies to therapeutic cancer vaccination, are discussed.
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PMID:Recombinant cancer vaccines based on viral vectors. 1560 88

Maxim is developing a subcutaneous formulation of histamine dihydrochloride (Ceplene, formerly known as Maxamine) for use as an adjuvant with interleukin (IL)-2 therapy for the potential treatment of metastatic melanoma, hepatitis C virus infection, acute myelogenous leukemia and renal cell carcinoma. In October 2002, the compound was in phase III trials for metastatic melanoma in Europe, Australia, Canada, Israel and the US. In November 2003, Maxim submitted an MAA to the EMEA for malignant melanoma in combination with IL-2.
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PMID:Histamine dihydrochloride (subcutaneous) Maxim. 1564 52

The cellular protein retinoic acid-inducible gene I (RIG-I) senses intracellular viral infection and triggers a signal for innate antiviral responses including the production of type I IFN. RIG-I contains a domain that belongs to a DExD/H-box helicase family and exhibits an N-terminal caspase recruitment domain (CARD) homology. There are three genes encoding RIG-I-related proteins in human and mouse genomes. Melanoma differentiation associated gene 5 (MDA5), which consists of CARD and a helicase domain, functions as a positive regulator, similarly to RIG-I. Both proteins sense viral RNA with a helicase domain and transmit a signal downstream by CARD; thus, these proteins share overlapping functions. Another protein, LGP2, lacks the CARD homology and functions as a negative regulator by interfering with the recognition of viral RNA by RIG-I and MDA5. The nonstructural protein 3/4A protein of hepatitis C virus blocks the signaling by RIG-I and MDA5; however, the V protein of the Sendai virus selectively abrogates the MDA5 function. These results highlight ingenious mechanisms for initiating antiviral innate immune responses and the action of virus-encoded inhibitors.
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PMID:Shared and unique functions of the DExD/H-box helicases RIG-I, MDA5, and LGP2 in antiviral innate immunity. 1611 71

The paramyxovirus Sendai (SV), is a well-established inducer of IFN-alphabeta gene expression. In this study we show that SV induces IFN-alphabeta gene expression normally in cells from mice with targeted deletions of the Toll-IL-1 resistance domain containing adapters MyD88, Mal, Toll/IL-1R domain-containing adaptor inducing IFN-beta (TRIF), and TRIF-related adaptor molecule TLR3, or the E3 ubiquitin ligase, TNFR-associated factor 6. This TLR-independent induction of IFN-alphabeta after SV infection is replication dependent and mediated by the RNA helicase, retinoic acid-inducible gene-I (RIG-I) and not the related family member, melanoma differentiation-associated gene 5. Furthermore, we characterize a RIG-I-like RNA helicase, Lgp2. In contrast to RIG-I or melanoma differentiation-associated gene 5, Lgp2 lacks signaling caspase recruitment and activation domains. Overexpression of Lgp2 inhibits SV and Newcastle disease virus signaling to IFN-stimulated regulatory element- and NF-kappaB-dependent pathways. Importantly, Lgp2 does not prevent TLR3 signaling. Like RIG-I, Lgp2 binds double-stranded, but not single-stranded, RNA. Quantitative PCR analysis demonstrates that Lgp2 is present in unstimulated cells at a lower level than RIG-I, although both helicases are induced to similar levels after virus infection. We propose that Lgp2 acts as a negative feedback regulator of antiviral signaling by sequestering dsRNA from RIG-I.
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PMID:The RNA helicase Lgp2 inhibits TLR-independent sensing of viral replication by retinoic acid-inducible gene-I. 1621 Jun 31

A growing family of cellular proteins encoding the caspase activation and recruitment domain (CARD) has a crucial role in immunity by sensing virus infection and signaling antiviral immune defenses. Four independent studies have identified a novel CARD-containing protein, variously called IPS-1, MAVS, VISA and Cardif, which is an essential signaling adaptor of the host defense mediating CARD-CARD interactions with retinoic acid inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDAS), sensors of virus infection. Disruption of this novel signaling pathway by hepatitis C virus (HCV) might provide a foundation for viral persistence.
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PMID:CARD games between virus and host get a new player. 1630 64

PEGylation of IFN-alpha has been used successfully to improve the pharmacokinetic properties and efficacy of the drug. To prepare a PEGylated form of human interferon-beta-1a (IFN-beta-1a) suitable for testing in vivo, we have synthesized 20 kDa mPEG-O-2-methylpropionaldehyde and used it to modify the N-terminal alpha-amino group of the cytokine. The PEGylated protein retained approximately 50% of the activity of the unmodified protein and had significantly improved pharmacokinetic properties following intravenous administration in rats. The clearance and volume of distribution at steady state were reduced approximately 30-fold and approximately 4-fold, respectively, resulting in a significant increase in systemic exposure as determined by the area under the curve. The elimination half-life of the PEGylated protein was approximately 13-fold greater than for the unmodified protein. The unmodified and PEGylated proteins were tested for their ability to inhibit the formation of radially oriented blood vessels entering the periphery of human SK-MEL-1 melanoma tumors in athymic nude homozygous (nu/nu) mice. In a single dose comparison study, administration of 1 x 10(6) units of unmodified IFN-beta-1a resulted in a 29% reduction in vessel number, while 1 x 10(6) units of PEGylated IFN-beta-1a resulted in a 58% reduction. Both treatments resulted in statistically significant reductions in mean vessel number as compared to the vehicle (control)-treated mice, with the PEGylated IFN-beta-1a-treated mice showing a statistically significantly greater reduction in mean vessel number as compared to the unmodified IFN-beta-1a-treated mice. In a multiple versus single dose comparison study, daily administration of 1 x 10(6) units of unmodified IFN-beta-1a for 9 days resulted in a 51% reduction in vessel number, while a single dose of 1 x 10(6) units of the PEGylated protein resulted in a 66% reduction. Both treatments resulted in statistically significant reductions in mean vessel number as compared to the vehicle-treated mice, with the PEGylated IFN-beta-1a-treated mice showing a statistically significantly greater reduction in mean vessel number as compared to the unmodified IFN-beta-1a-treated mice. Therefore, the improved pharmacokinetic properties of the modified protein translated into improved efficacy. Since unmodified IFN-beta is used for the treatment of multiple sclerosis and hepatitis C virus infection, a PEGylated form of the protein such as 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-beta-1a may serve as a useful adjunct for the treatment of these diseases. In addition, the antiangiogenic effects of PEGylated IFN-beta-1a may be harnessed for the treatment of certain cancers, either as a sole agent or in combination with other antitumor drugs.
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PMID:N-terminally PEGylated human interferon-beta-1a with improved pharmacokinetic properties and in vivo efficacy in a melanoma angiogenesis model. 1641 67

Oncolytic viral therapy provides a promising approach to treat certain human malignancies. These vectors improve on replication-deficient vectors by increasing the viral load within tumors through preferential viral replication within tumor cells. However, the inability to efficiently propagate throughout the entire tumor and infect cells distant from the injection site has limited the capacity of oncolytic viruses to achieve consistent therapeutic responses. Here we show that the spread of the oncolytic herpes simplex virus (HSV) vector MGH2 within the human melanoma Mu89 is limited by the fibrillar collagen in the extracellular matrix. This limitation seems to be size specific as nanoparticles of equivalent size to the virus distribute within tumors to the same extent whereas smaller particles distribute more widely. Due to limited viral penetration, tumor cells in inaccessible regions continue to grow, remaining out of the range of viral infection, and tumor eradication cannot be achieved. Matrix modification with bacterial collagenase coinjection results in a significant improvement in the initial range of viral distribution within the tumor. This results in an extended range of infected tumor cells and improved virus propagation, ultimately leading to enhanced therapeutic outcome. Thus, fibrillar collagen can be a formidable barrier to viral distribution and matrix-modifying treatments can significantly enhance the therapeutic response.
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PMID:Degradation of fibrillar collagen in a human melanoma xenograft improves the efficacy of an oncolytic herpes simplex virus vector. 1651 May 65

Sialic acid is known to be an essential part of influenza virus receptors, but the specific identity of the receptor molecules on target cells is still not defined. In particular, the relative roles played by cellular sialylglycoproteins and gangliosides in virus entry into target cells remain unclear. To test whether gangliosides are essential for virus infection, we used the GM-95 mutant cell line of mouse B16 melanoma which lacks synthesis of major glycosphingolipids including gangliosides. We found that GM-95 cells grown in serum-containing medium harboured substantial amounts of ganglioside receptors for influenza virus due to incorporation of serum gangliosides. To obtain ganglioside-free cells, we adapted GM-95 cells to growth in defined serum-free (sf) medium. Ganglioside-free GM-95-sf cells could be infected by avian and human influenza A viruses and produced infectious virus progeny demonstrating that gangliosides were neither absolutely necessary for the early nor for the late stages of the infection. However, sensitivity of the GM-95-sf cells to the viruses was 2-4 times lower than that of the ganglioside-containing parent cell line. Further studies are needed to specify whether this effect was due to the lack of gangliosides, neutral glycosphingolipids, or other effects.
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PMID:Gangliosides are not essential for influenza virus infection. 1657 28

Upon viral infection, host cells trigger antiviral immune responses by inducing type I IFN and inflammatory cytokines. dsRNA generated during viral replication is recognized by the cytoplasmic RNA helicases retinoic acid-inducible gene I and melanoma differentiation-associated gene 5, which interact with an adaptor, IFN-beta promoter stimulator-1, to activate the transcription factors NF-kappaB and IFN regulatory factor 3. In this article we demonstrate that caspase-8 and caspase-10 are involved in these pathways. Both caspases were cleaved during dsRNA stimulation, and overexpression of a cleaved form of these caspases activated NF-kappaB. Knockdown of caspase-10 or caspase-8 in a human cell line resulted in the reduction of inflammatory cytokine production. Cells derived from caspase-8-deficient mice also showed reduced expression of inflammatory cytokines as well as NF-kappaB activation. Furthermore, the Fas-associated death domain protein interacted with these two caspases and IFN-beta promoter stimulator 1. These results indicate that caspase-8 and caspase-10 are essential components that mediate NF-kappaB-dependent inflammatory responses in antiviral signaling.
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PMID:Roles of caspase-8 and caspase-10 in innate immune responses to double-stranded RNA. 1658 40


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