Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A tumour-specific polypeptide designated U90 is one of a set of polypeptides which are encoded by the host cell and are specific for the transformed cell state, being immunoprecipitated by the sera of tumour-bearing animals. The interest in these tumour-specific polypeptides centres on the finding that they are also recognized by antisera raised against herpes simplex virus type 2 (HSV-2)-infected cells, implying some role for HSV-2 in tumorigenesis. The peptide map of HSV-2-induced U90 is indistinguishable from that of U90 present in uninfected tumour cells, including mouse cells transformed by human papillomavirus type 16. In tumour cells, U90 is located principally in the plasma membrane fraction and cannot be induced by heat shock, glucose starvation, or treatment with tunicamycin or calcium ionophore. U90 is not related to either the heat shock protein of Mr 90,000 (HSP90) or the glucose-related polypeptide of Mr 94,000 (GRP94) as determined by peptide mapping and the use of monospecific, monoclonal and antipeptide antibodies. This suggests that U90 is a novel transformation-specific protein which can be induced by infection with HSV-2.
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PMID:A transformation-specific polypeptide distinct from heat shock proteins is induced by herpes simplex virus type 2 infection. 166 99

To date, the acquired immunodeficiency syndrome (AIDS) has been identified in over 50 children in the US, including those with associated hemophilia, high-risk environmental factors (Haitian background, parental intravenous drug abuse, or prostitution), and blood transfusions. The evaluation of an infant or young child in whom AIDS is suspected requires exclusion of congenital disorders of immune function. A specific test is not currently available, but inclusion criteria for childhood AIDS have been developed. The diseases accepted as indicative of underlying cellular immunodeficiency children are the same as those used in defining AIDS in adults, with the exclusion of congenital infections such as toxoplasmosis or herpes simplex virus infection in the 1st month of life or cytomegalovirus infection in the 1st 6 months of life. Specific conditions that must be excluded in children are primary immunodeficiency diseases (e.g., DiGeorge syndrome, Wiskott-Aldrich syndrome, ataxia-telangiectasia, neutrophil function abnormality) and secondary immuno-deficiency associated with immunosuppressive therapy, lymphoreticular malignancy, or starvation. Almost all young children with AIDS have hepatosplenomegaly, interstitial pneumonitis, and poor growth. The average age of 36 US child AIDS victims studied in detail was 5 months at presentation with findings suggestive of severe immunodeficiency. Mucocutaneous candidiasis was present in 75% of these 36 children, and Pneumocystis carinii and cytomegalovirus were each isolated from 30% of cases. Normal T4:T8 ratios occur in about 15% of pediatric AIDS cases. Laboratory evidence of polyclonal hypergammaglobulinemia generally supports the AIDS diagnosis. Recurrent infection and malnutrition are major problems in the clinical management of child AIDS patients.
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PMID:Acquired immune deficiency syndrome in childhood. 298 8

Plasmid pJM81 contains a Herpes simplex virus thymidine kinase (TK) gene that is expressed in yeast. Cells containing the plasmid utilize thymidine (TdR) and the analogue 5-bromodeoxyuridine (BUdR) for specific incorporation into DNA. TdR auxotrophs, harboring plasmid pJM81 and a mutation in the yeast gene TMP1 require high concentrations of TdR (300 micrograms/ml) to support normal growth rates and the wild-type mitochondrial genome (rho+) cannot be maintained. We have identified a yeast gene, TUT1, in which recessive mutations allow efficient utilization of lower concentrations of TdR. Strains containing the mutations tmp1 and tut1, as well as plasmid pJM81, form colonies at 2 micrograms/ml TdR, grow at nearly normal rates and maintain the rho+ genome at 50 micrograms/ml TdR. These strains can be used to radiolabel DNA specifically and to synchronize DNA replication by TdR starvation. In addition, the substitution of BUdR for TdR allows the selective killing of DNA-synthesizing cells by 310-nm irradiation and allows the separation of replicated and unreplicated forms of DNA by CsCl equilibrium density banding. We also describe a unique, generally applicable system for cloning mutant alleles that exploits the fact that Tk+ yeast cells are sensitive to 5-fluorodeoxyuridine (FUdR) and that gene conversions can occur between a yeast chromosome and a TK-containing plasmid.
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PMID:Thymidine utilization by tut mutants and facile cloning of mutant alleles by plasmid conversion in S. cerevisiae. 302 59

Proteose-peptone-activated mouse macrophages can prevent productive infection by herpes simplex virus in neighboring cells in vitro whether or not those cells belong to the same animal species. The effect does not require contact between the macrophages and the infected cells, may be prevented by adding extra arginine to the medium, and may be reversed when extra arginine is added 24 h after the macrophages. Arginase activity was found both intracellularly and released from the macrophages. The extracellular enzyme is quite stable; 64% activity was found after 48 h of incubation at 37 degrees C in tissue culture medium. No evidence was found that the inefficiency of virus replication in macrophages was due to self-starvation by arginase. As might be predicted macrophages can, by the same mechanism, limit productive infection by vaccinia virus.
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PMID:Inhibition of herpes simplex virus multiplication by activated macrophages: a role for arginase? 628 97

All herpes simplex virus (HSV) infected cell-specific polypeptides (ICSPs) were synthesized in the presence of lithium at a concentration (60 mM) inhibitory to the production of infectious virus. Yields of certain ICSPs were increased and others, in particular glycoprotein C, decreased. HSV DNA synthesis was completely inhibited; synthesis and in vitro activities of HSV DNA polymerase and thymidine kinase were decreased but to a degree insufficient to account for the complete inhibition of HSV DNA synthesis. HSV DNA synthesis was inhibited to an equivalent degree by either incubation with 60 mM-lithium or by potassium starvation; both procedures decreased intracellular potassium by an equivalent amount as adjudged by X-ray microanalysis. We conclude that lithium inhibits HSV DNA synthesis by displacement of potassium from a potassium-dependent biochemical reaction or by other physiological changes brought about by the loss of cellular potassium. The possibility that lithium also directly inhibits a virus replicative event cannot be excluded.
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PMID:The effects of lithium and potassium on macromolecular synthesis in herpes simplex virus-infected cells. 839 11

In this paper we demonstrate the use of recombinant viral vectors derived from herpes simplex virus type 1 (HSV1) to transfer reporter genes in vitro into rat anterior pituitary cells grown in primary cultures and the anterior pituitary tumour cell lines GH3 and AtT20. The three vectors used were, tsK/beta-galactosidase (beta-gal), tsK/CRH and tsK/TIMP, the corresponding transgene products respectively being E. coli beta-gal, pre-procorticotropin releasing hormone (ppCRH), and the chimeric protein TIMP/Thy1 (tissue inhibitor of metalloproteinases (TIMP)/linked to the carboxy terminus of Thy1 which confers the addition of a glycolipid glycosyl-phosphatidylinositol anchor in the ER). Double labelling immunofluorescence experiments to detect reporter proteins and transduced cell types indicated that the three vectors could transfer and express the reporter genes in normal and tumour anterior pituitary cells. Virus infection of pituitary cells was characterised, and it was shown that infection with tsK/beta-gal at multiplicities of infection (MOI)=10, 100% of tumour and non-endocrine anterior pituitary cells expressed beta-gal, whereas 75% endocrine anterior pituitary cells expressed the transgene. Long-term expression studies after infection with tsK/beta-gal indicated that anterior pituitary cells in primary cultures expressed the transgene for significant longer periods than tumour anterior pituitary cells. Growth arrest by serum starvation markedly decreased the frequency of transgene expression in anterior pituitary cells following infection with tsK/beta-gal. Transgenic products expressed from tsK were targeted to their correct intracellular domain in both anterior pituitary cells in primary cultures and in pituitary tumour cell lines. We conclude that transgenes can be delivered into anterior pituitary cells in primary culture and pituitary tumour cell lines using tsK derived HSV1 vectors. The prospect of employing viral vectors to transfer genes into endocrine cells opens up the potential exploration of various molecular aspects of pituitary cell function both in vitro and in vivo, as well as the use of gene transfer into the pituitary for potentially therapeutic applications, such as the treatment of pituitary tumours.
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PMID:Use of recombinant herpes simplex virus type 1 vectors for gene transfer into tumour and normal anterior pituitary cells. 970 88

A new strategy in anticancer gene therapy uses stress-responsive cellular promoters that offer the advantage of enhanced gene expression in a variety of tumors. Although the feasibility of their selective expression has been demonstrated, functional evidence of their ability to activate therapeutic agents within the tumor environment leading to tumor eradication has not been established. Glucose deprivation, chronic anoxia, and acidic pH known to persist in poorly vascularized solid tumors strongly induce the transcription of the glucose-regulated protein 78 (grp78) gene, which encodes an Mr 78,000 stress-inducible protein. In this report, we tested directly the efficacy of the grp78 promoter in a retroviral system to drive the expression of the herpes simplex virus-thymidine kinase (HSVtk) suicide gene, using a murine fibrosarcoma model, in the context of their syngeneic, immunocompetent hosts. Our results showed that under glucose starvation conditions, the expression of HSVTK was enhanced in tumor cells where the HSVtk gene was driven by the internal grp78 promoter, in contrast to the Moloney murine leukemia virus long terminal repeat, where suppression was observed. We further demonstrated that in vivo, HSVTK expression was elevated to much higher levels inside tumors when driven by the internal grp78 promoter, resulting in complete eradication of sizable tumor mass, with no recurrence of tumor growth. Our study suggests that the glucose starvation-inducible grp78 promoter could be useful for enhanced expression of a variety of therapeutic agents within the solid tumor environment.
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PMID:Use of the glucose starvation-inducible glucose-regulated protein 78 promoter in suicide gene therapy of murine fibrosarcoma. 1039 51

The eIF2alpha kinases are a family of evolutionarily conserved serine/threonine kinases that regulate stress-induced translational arrest. Here, we demonstrate that the yeast eIF2alpha kinase, GCN2, the target phosphorylation site of Gcn2p, Ser-51 of eIF2alpha, and the eIF2alpha-regulated transcriptional transactivator, GCN4, are essential for another fundamental stress response, starvation-induced autophagy. The mammalian IFN-inducible eIF2alpha kinase, PKR, rescues starvation-induced autophagy in GCN2-disrupted yeast, and pkr null and Ser-51 nonphosphorylatable mutant eIF2alpha murine embryonic fibroblasts are defective in autophagy triggered by herpes simplex virus infection. Furthermore, PKR and eIF2alpha Ser-51-dependent autophagy is antagonized by the herpes simplex virus neurovirulence protein, ICP34.5. Thus, autophagy is a novel evolutionarily conserved function of the eIF2alpha kinase pathway that is targeted by viral virulence gene products.
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PMID:Regulation of starvation- and virus-induced autophagy by the eIF2alpha kinase signaling pathway. 1175 70

Cancer gene therapy with the aid of herpes simplex virus type 1 thymidine kinase gene (HSV-TK) and anti-herpes drug ganciclovir (GCV) has been widely used and its efficacy has been demonstrated in a variety of different malignant cells and animal tumor models. It is also commonly accepted, however, that this gene therapy regimen needs to be enhanced for a true clinical success. We studied whether polyamine biosynthesis inhibition by 2-difluoromethylornithine (DFMO), a clinically tested and well-tolerated chemotherapeutic drug, can increase the cytotoxicity of HSV-TK/GCV in 9L rat glioma cells. Our initial experiments showed that polyamine depletion actually protected the cells from cytotoxicity if GCV treatment was started too early after removal of DFMO. Analyses of cell growth, intracellular polyamine pools and cell cycle phase distribution suggested that later initiation of GCV treatment would be more beneficial due to increased proportion of cells in the middle of the cell cycle S phase. When the cells were exposed to GCV 3 or 4 days after removal of DFMO from growth medium, the cytotoxicity was increased up to 2.5-fold. We also verified whether cell cycle blockage per se could yield similar effect as DFMO. Our results from serum deprivation experiments showed that, despite of apparent cell growth and cell cycle phase distribution effects, serum starvation was weaker enhancer of HSV-TK/GCV cytotoxicity than DFMO. Finally, the general utility of HSV-TK/GCV + DFMO combination was tested in another tumor cell type, human prostate carcinoma cell line DU-145. DFMO sensitized these cells to HSV-TK/GCV cytotoxicity, but the effect was less prominent than in 9L cells. In conclusion, we have demonstrated that a correctly timed induction of DFMO-mediated polyamine biosynthesis inhibition can enhance the efficiency of HSV-TK/GCV gene therapy in vitro. The observed synergistic effect is potentially useful in clinical trials because, as opposed to use of other cell cycle-altering drugs, DFMO has already been tested in the treatment of human tumors and used as chemo preventive regimen with excellent tolerability.
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PMID:Polyamine biosynthesis inhibition enhances HSV-1 thymidine kinase/ganciclovir-mediated cytotoxicity in tumor cells. 1256 63

Plasmids expressing the herpes simplex virus type 1 (HSV-1) latency-associated transcript (LAT) reduce apoptosis in transient transfection assays in tissue culture. LAT also reduces apoptosis in the context of the virus in trigeminal ganglia of rabbits and mice at approximately 6-7 days post-infection during the switch from acute to latent HSV-1 infection, a time at which LAT is the only abundantly transcribed viral gene. Analysis of LAT's anti-apoptosis function is complicated in tissue culture by the expression of at least five additional viral gene products that can block apoptosis, and by the fact that apoptosis usually occurs in only a fraction of the cells. Here, we present two approaches for detecting LAT's anti-apoptosis activity in the context of the whole virus in tissue culture. Using a combination of serum starvation to both partially synchronize the cells and induce apoptosis, and Hoechst staining to detect chromatin condensation, we found that there was a small window of time post-infection during which Schwann cells infected with the LAT(-) mutant dLAT2903 reproducibly had more apoptotic nuclei than identically treated cells infected with the LAT(+) parental virus HSV-1 strain McKrae. Using serum starvation and/or UV treatment and a method to isolate fragmented DNA away from large chromosomal DNA, we found a similar window of time post-infection during which Neuro2A cells infected with dLAT2903 had increased DNA fragmentation (as judged by a DNA laddering assay) compared to identically treated cells infected with wild type McKrae or the LAT(+) marker rescued dLAT2903R virus. These assays should permit the use of culture assays, rather than labor intensive animal models, to examine LAT's anti-apoptosis activity in the context of the virus in a large number of existing LAT mutant viruses.
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PMID:Methods for detecting the HSV-1 LAT anti-apoptosis activity in virus infected tissue culture cells. 1515 63


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