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1.
Virus Genes ; 55(3): 421-424, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30877415

ABSTRACT

A novel gamma-retroviral sequence (7912 bp), inclusive of both partial 5' and 3' long terminal repeat regions, was identified from the brain of a black flying-fox (Pteropus alecto), Queensland, Australia. The sequence was distinct from other retroviral sequences identified in bats and showed greater identity to Koala, Gibbon ape leukaemia, Melomys burtoni and Woolly monkey retroviruses, forming their own phylogenetic clade. This finding suggests that these retroviruses may have an unknown common ancestor and that further investigation into the diversity of gamma-retroviruses in Australian Pteropus species may elucidate their evolutionary origins.


Subject(s)
Chiroptera/virology , Hylobates/virology , Phascolarctidae/virology , Retroviridae/genetics , Animals , Australia , Chiroptera/genetics , Hylobates/genetics , Leukemia Virus, Gibbon Ape/genetics , Phascolarctidae/genetics , Phylogeny , Sarcoma Virus, Woolly Monkey/genetics
2.
Clin Cancer Res ; 23(9): 2177-2185, 2017 May 01.
Article in English | MEDLINE | ID: mdl-27864420

ABSTRACT

Purpose: RNA sequencing (RNA-seq) has recently proved to be effective for revealing novel virus-tumor associations. To get a thorough investigation of virus-glioma associations, we screened viruses in gliomas with RNA-seq data from the Chinese Glioma Genome Atlas project.Experimental Design: In total, 325 samples were enrolled into this study. Reads that failed to map to the human genome were aligned to viral genomes and screened for potential virus-derived transcripts. For quantification, VPKM was calculated according to mapped reads weighted by genome sizes and sequencing depth.Results: We observed that viruses tended to concertedly express in a certain subgroup of patients. Survival analysis revealed that individuals who were infected with Simian virus 40 (SV40) or woolly monkey sarcoma virus (WMSV) had a significantly shorter overall survival than those uninfected. A multivariate Cox proportional hazards model, taking clinical and molecular factors into account, was applied to assess the prognostic value of SV40 and WMSV. Both SV40 and WMSV were independent prognostic factors for predicting patient's survival in lower-grade gliomas. Subsequent gene analysis demonstrated that SV40 was correlated with regulation of transcription, whereas WMSV was correlated with cell-cycle phase, which indicated frequent proliferation of tumor cells.Conclusions: RNA-seq was sufficient to identify virus infection in glioma samples. SV40 and WMSV were identified to be prognostic markers for patients with lower-grade gliomas and showed potential values for targeting therapy. Clin Cancer Res; 23(9); 2177-85. ©2016 AACR.


Subject(s)
Endogenous Retroviruses/genetics , Glioma/virology , Sarcoma Virus, Woolly Monkey/genetics , Simian virus 40/genetics , Cell Proliferation/genetics , Endogenous Retroviruses/isolation & purification , Endogenous Retroviruses/pathogenicity , Female , Genome, Human , Glioma/genetics , Glioma/pathology , Humans , Male , Neoplasm Grading , Proportional Hazards Models , Sarcoma Virus, Woolly Monkey/isolation & purification , Sarcoma Virus, Woolly Monkey/pathogenicity , Sequence Analysis, RNA , Simian virus 40/isolation & purification , Simian virus 40/pathogenicity , Survival Analysis , Transcription, Genetic
3.
J Biol Chem ; 281(3): 1636-43, 2006 Jan 20.
Article in English | MEDLINE | ID: mdl-16293630

ABSTRACT

Binding of lipopolysaccharide (LPS) to macrophages results in proinflammatory cytokine secretion. In extreme cases it leads to endotoxic shock. A few innate immunity antimicrobial peptides (AMPs) neutralize LPS activity. However, the underlying mechanism and properties of the peptides are not yet clear. Toward meeting this goal we investigated four AMPs and their fluorescently labeled analogs. These AMPs varied in composition, length, structure, and selectivity toward cells. The list included human LL-37 (37-mer), magainin (24-mer), a 15-mer amphipathic alpha-helix, and its D,L-amino acid structurally altered analog. The peptides were investigated for their ability to inhibit LPS-mediated cytokine release from RAW264.7 and bone marrow-derived primary macrophages, to bind LPS in solution, and when LPS is already bound to macrophages (fluorescence spectroscopy and confocal microscopy), to compete with LPS for its binding site on the CD14 receptor (flow cytometry) and affect LPS oligomerization. We conclude that a strong binding of a peptide to LPS aggregates accompanied by aggregate dissociation prevents LPS from binding to the carrier protein lipopolysaccharide-binding protein, or alternatively to its receptor, and hence inhibits cytokine secretion.


Subject(s)
Endotoxins/chemistry , Lipopolysaccharides/immunology , Peptides/immunology , Amino Acid Sequence , Binding Sites , Humans , Immunity, Innate , Interleukin-6/genetics , Macrophages/immunology , Microbial Sensitivity Tests , Molecular Sequence Data , Neutralization Tests , Peptides/chemistry , Peptides/pharmacology , RNA, Messenger/genetics , Sarcoma Virus, Woolly Monkey , Tumor Necrosis Factor-alpha/genetics
4.
Nephrol Ther ; 2 Suppl 4: S274-82, 2006 Sep.
Article in French | MEDLINE | ID: mdl-17373270

ABSTRACT

Recombinant human erythropoietin (rHuEPO) has transformed the management chronic renal failure (CKD) and considerably improved the outcome of patients on regular chronic dialysis. However, a significant number of patients fail to respond to high of Erythropoiesis-stimulating agents (ESAs) and several causes of inadequate response to epoetin therapy have been identified. Some factors, such as gender, age, length of time on dialysis, type of dialysis and co-morbidities such as hemoglobinopathy, are not susceptible to clinical intervention. However, many other factors can be adjusted. Iron deficiency, whether functional or absolute, is the most common factor that limits the response to rHuEPO. Monitoring of iron parameters and a large use of iron supplementation result in an efficient epoetin response. Infection and inflammation have been shown to reduce responsiveness to ESAs by disrupting iron metabolism and increasing the release of pro-inflammatory cytokines that inhibit erythropoiesis. Increase dialysis dose is associated with improvements in anemia correction and reduced requirements for ESAs. Severe hyperparathyroidism and aluminum overload lead to a reduced number of responsive erythroid progenitor cells. Finally, a number of nutritional factors, such as deficiencies of carnitine, vitamin B12, folic acid, and vitamin C, are susceptible to alter erythropoiesis. Optimizing patient response to ESAs therefore requires consideration of many of well-established factors and is important for both patient outcomes and cost of treatment.


Subject(s)
Anemia/drug therapy , Anemia/etiology , Erythropoietin/therapeutic use , Kidney Failure, Chronic/complications , Cytokines/metabolism , Erythropoiesis/drug effects , Humans , Inflammation/physiopathology , Iron Deficiencies , Recombinant Proteins , Sarcoma Virus, Woolly Monkey , Vitamins/metabolism
6.
Transplant Proc ; 37(5): 2115-7, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15964354

ABSTRACT

Mycotic infections in various organ transplant recipients represent severe and often fatal complications. Aspergillosis isolated from the urinary tract occurs quite infrequently in renal transplant recipients. Besides, fungus balls are rare causes of ureteral obstruction. We report a 51-year-old patient with the diagnosis of ureteral obstruction caused by aspergillosis in the early post-renal transplant period, who unfortunately died with the clinical picture of disseminated infection and its complications.


Subject(s)
Aspergillosis/diagnosis , Aspergillus/isolation & purification , Kidney Transplantation , Postoperative Complications/microbiology , Ureteral Obstruction/microbiology , Humans , Living Donors , Male , Middle Aged , Sarcoma Virus, Woolly Monkey
7.
Kidney Int ; 67(4): 1622-9, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15780120

ABSTRACT

BACKGROUND: Human immunodeficiency virus-associated nephropathy (HIVAN) has become the third leading cause of end-stage renal disease (ESRD) in African Americans, and is expected to grow exponentially. Highly active antiretroviral therapy (HAART) has significantly prolonged the survival of patients with HIV infection. Despite the growing number of HIV-positive dialysis patients with prolonged life expectancy, kidney transplantation with immunosuppression has been declined because it is considered a waste of scarce donor kidneys due to potential increases in morbidity and mortality. METHODS: The institutional review board of Drexel University College of Medicine and Hahnemann University Hospital approved this prospective study. The aim was to find out safety and success of kidney transplantation, and the effect of immunosuppression on HIV infection. Forty HIV-positive dialysis patients received kidney transplantation between February 2001 and January 2004. Patient inclusion criteria were maintenance of HAART, plasma HIV-1 RNA of <400 copies/mL, absolute CD4 counts of 200 cells/muL or more. Immunosuppression was basiliximab induction and maintenance with cyclosporine, sirolimus, and steroids. HAART was continued post-transplant. Acute rejections were diagnosed by biopsy and treated with methylprednisolone. Surveillance biopsies were completed at 1, 6, 12, and 24 months, and evaluated for subclinical acute rejection, chronic allograft nephropathy, and HIVAN. RESULTS: One- and 2-year actuarial patient survival was 85% and 82%, respectively, and graft survival was 75% and 71%, respectively. Plasma HIV-1 RNA remained undetectable, and CD4 counts remained in excess of 400 cells per muL with no evidence of AIDS for up to 2 years. CONCLUSION: One- and 2-year graft survival is comparable to other high-risk populations receiving kidney transplantation. One- and 2-year patient survival is higher than HIV patients maintained on dialysis. Immunosuppression does not adversely affect HIV recipients maintained on HAART in the short term.


Subject(s)
AIDS-Associated Nephropathy/surgery , Kidney Transplantation/methods , Safety , Candidiasis, Oral/prevention & control , Dapsone/therapeutic use , Female , Graft Rejection/immunology , HIV Seropositivity/complications , HIV Seropositivity/immunology , Humans , Kidney Failure, Chronic/etiology , Kidney Failure, Chronic/surgery , Kidney Transplantation/immunology , Kidney Transplantation/mortality , Male , Middle Aged , Nystatin/therapeutic use , Pneumocystis Infections/prevention & control , Retrospective Studies , Sarcoma Virus, Woolly Monkey , Survival Analysis , Treatment Outcome
8.
Pathol Biol (Paris) ; 53(2): 88-91, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15708652

ABSTRACT

In this study, a survey was conducted to investigate the possible effects of long term usage of mobile phone (MP) on eyes. The studied symptoms are blurring of vision, redness on the eyes, vision disturbance, secretion of the eyes, inflammation in the eyes and lacrimation of the eyes. There is no effect on redness on the eyes and vision disturbance, but some statistical evidences are found that MP may cause blurring of vision, secretion of the eyes, inflammation in the eyes and lacrimation of the eyes. These results suggest an awareness of the symptoms and sensations.


Subject(s)
Cell Phone , Eye Diseases/etiology , Analysis of Variance , Eye Diseases/epidemiology , Health Status , Health Surveys , Humans , Inflammation , Sarcoma Virus, Woolly Monkey , Sensation Disorders/epidemiology , Sensation Disorders/etiology , Surveys and Questionnaires , Tears/metabolism , Turkey/epidemiology , Vision Disorders/epidemiology , Vision Disorders/etiology
9.
Transplant Proc ; 36(2 Suppl): 314S-317S, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15041360

ABSTRACT

The introduction of cyclosporine into clinical practice of thoracic organ transplantation had a dramatic and positive effect on both short- and long-term survival. Today, the majority of patients are still treated with this drug, and different immunosuppressive combination therapies have further resulted in improved long-term survival. Such combinations to calcineurin inhibitors include prednisolone, mycophenolate mofetil, azathioprine, and Rapamycin. Based on data from our own institution 1- and 5-year survival rates of 86% and 78% can be obtained after heart transplantation and 76% and 59% after lung transplantation. Causes of death are described. Future immunosuppressive strategies will have to concentrate further on the omission of organ-damaging side effects. Also, not a single compound or combination for immunosuppression after thoracic organ transplantation has proved to be effective in cases with chronic rejection (eg, transplant vasculopathy in heart transplantation and bronchiolitis obliterans in lung transplantation). Moreover, with current survival data in mind, quality of life has to be considered a major focus for future designs of immunosuppressive protocols.


Subject(s)
Cyclosporine/therapeutic use , Heart Transplantation/immunology , Lung Transplantation/immunology , Drug Therapy, Combination , Heart Transplantation/mortality , Immunosuppressive Agents/therapeutic use , Lung Transplantation/mortality , Postoperative Complications/immunology , Postoperative Complications/mortality , Retrospective Studies , Sarcoma Virus, Woolly Monkey , Survival Analysis
11.
Am J Hum Genet ; 73(4): 849-62, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14505273

ABSTRACT

Myotonic dystrophy (DM), the most common form of muscular dystrophy in adults, can be caused by a mutation on either chromosome 19 (DM1) or 3 (DM2). In 2001, we demonstrated that DM2 is caused by a CCTG expansion in intron 1 of the zinc finger protein 9 (ZNF9) gene. To investigate the ancestral origins of the DM2 expansion, we compared haplotypes for 71 families with genetically confirmed DM2, using 19 short tandem repeat markers that we developed that flank the repeat tract. All of the families are white, with the majority of Northern European/German descent and a single family from Afghanistan. Several conserved haplotypes spanning >700 kb appear to converge into a single haplotype near the repeat tract. The common interval that is shared by all families with DM2 immediately flanks the repeat, extending up to 216 kb telomeric and 119 kb centromeric of the CCTG expansion. The DM2 repeat tract contains the complex repeat motif (TG)(n)(TCTG)(n)(CCTG)(n). The CCTG portion of the repeat tract is interrupted on normal alleles, but, as in other expansion disorders, these interruptions are lost on affected alleles. We examined haplotypes of 228 control chromosomes and identified a potential premutation allele with an uninterrupted (CCTG)(20) on a haplotype that was identical to the most common affected haplotype. Our data suggest that the predominant Northern European ancestry of families with DM2 resulted from a common founder and that the loss of interruptions within the CCTG portion of the repeat tract may predispose alleles to further expansion. To gain insight into possible function of the repeat tract, we looked for evolutionary conservation. The complex repeat motif and flanking sequences within intron 1 are conserved among human, chimpanzee, gorilla, mouse, and rat, suggesting a conserved biological function.


Subject(s)
Chromosomes, Human, Pair 19 , Chromosomes, Human, Pair 3 , Evolution, Molecular , Founder Effect , Mutation , Myotonic Dystrophy/genetics , Repetitive Sequences, Nucleic Acid , Adult , Base Sequence , Chromosome Mapping , Conserved Sequence , DNA Primers , Europe/epidemiology , Family , Haplotypes , Humans , Introns , Microsatellite Repeats/genetics , Molecular Sequence Data , Myotonic Dystrophy/classification , Polymorphism, Genetic , Recombination, Genetic , Reference Values , Sarcoma Virus, Woolly Monkey , Trinucleotide Repeats/genetics
12.
Cancer Sci ; 94(8): 725-8, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12901799

ABSTRACT

The present study was carried out to characterize the causative genetic mutation in a medium-sized Malaysian Chinese pedigree of three generations affected with familial adenomatous polyposis (FAP). Clinical data and genetic studies revealed considerable phenotypic variability in affected individuals in this family. Blood was obtained from members of the FAP-01 family and genomic DNA was extracted. Mutation screening of the adenomatous polyposis coli (APC) gene was carried out using the single strand conformation polymorphism (SSCP) technique. The possibility of exon skipping was predicted by splicing motif recognition software (ESEfinder release2.0). SSCP results showed mobility shifts in exon 8 of the APC gene which segregated with affected members of the family. Sequence analysis revealed that the affected individuals are heterozygous for a C847T transition, whilst all the unaffected family members and control individuals are homozygous C at the same position. This nucleotide substitution generates a stop codon at amino acid position 283, in place of the usual arginine (Arg283Ter). We conclude that an Arg283Ter mutation in the APC gene is causative of the FAP phenotype in this family, although there is considerable variation in the presentation of this disease among affected individuals. Computational analysis predicts that this mutation occurs within sequences that may function as splicing signals, so that the sequence change may affect normal splicing.


Subject(s)
Adenomatous Polyposis Coli/genetics , Codon, Nonsense/genetics , Exons/genetics , Genes, APC , Amino Acid Substitution , Arginine , Asian People , Base Sequence , Female , Humans , Malaysia , Male , Pedigree , Polymorphism, Single-Stranded Conformational , Sarcoma Virus, Woolly Monkey
13.
J Immunol ; 163(12): 6892-7, 1999 Dec 15.
Article in English | MEDLINE | ID: mdl-10586091

ABSTRACT

Leader binding protein-1 (LBP-1)/late SV40 factor (LSF) and ying yang-1 (YY1) transcription factors are involved in the regulation of HIV expression. In particular, YY1 and LBP-1 have been shown to cooperate in repressing HIV-1-long terminal repeat reporter gene expression by in vitro cotransfection experiments. However, no information is available on the levels of expression and activation of these transcription factors in PBMC of HIV-infected individuals. Therefore, we have evaluated the expression and DNA binding activity of YY1 and LBP-1 (LSF) in PBMC of HIV-infected individuals before, during, and after administration of IL-2 in association with antiretroviral therapy (ART), a regimen under consideration for broad clinical use in this disease based on its ability to stably raise the absolute number of circulating CD4+ T lymphocytes. Both YY1- and LBP-1 (LSF)-DNA binding were profoundly down-modulated during administration of IL-2/ART, and a proteolytic activity probably responsible for the reduced expression of the two cellular transcription factors was found activated in PBMC of individuals receiving the immunotherapeutic regimen. This study is the first evidence of modulation of cellular transcription factors following IL-2/ART administration and provides a potential correlate of the transient raises in plasma viremia early reported in patients receiving IL-2 in the absence of ART, thus underscoring the importance of always administering this cytokine to HIV-infected individuals together with potent antiretrovirals.


Subject(s)
DNA-Binding Proteins/antagonists & inhibitors , Down-Regulation/immunology , HIV Seropositivity/immunology , Interleukin-2/administration & dosage , Recombinant Proteins/administration & dosage , Sarcoma Virus, Woolly Monkey/immunology , Transcription Factors/antagonists & inhibitors , Adult , Antibody Specificity , Blotting, Western , DNA/metabolism , DNA-Binding Proteins/biosynthesis , DNA-Binding Proteins/immunology , DNA-Binding Proteins/metabolism , Down-Regulation/drug effects , Endopeptidases/metabolism , Erythroid-Specific DNA-Binding Factors , Female , HIV Seropositivity/enzymology , HIV Seropositivity/metabolism , Humans , Hydrolysis , Injections, Subcutaneous , Interleukin-2/genetics , Interleukin-2/pharmacology , Male , Middle Aged , Protein Binding/drug effects , Protein Binding/immunology , RNA-Binding Proteins , Recombinant Proteins/pharmacology , Transcription Factors/biosynthesis , Transcription Factors/immunology , Transcription Factors/metabolism , YY1 Transcription Factor
14.
J Biol Chem ; 274(15): 10582-9, 1999 Apr 09.
Article in English | MEDLINE | ID: mdl-10187853

ABSTRACT

The cell surface retention sequence (CRS) binding protein-1 (CRSBP-1) is a newly identified membrane glycoprotein which is hypothesized to be responsible for cell surface retention of the oncogene v-sis and c-sis gene products and other secretory proteins containing CRSs. In simian sarcoma virus-transformed NIH 3T3 cells (SSV-NIH 3T3 cells), a fraction of CRSBP-1 was demonstrated at the cell surface and underwent internalization/recycling as revealed by cell surface 125I labeling and its resistance/sensitivity to trypsin digestion. However, the majority of CRSBP-1 was localized in intracellular compartments as evidenced by the resistance of most of the 35S-metabolically labeled CRSBP-1 to trypsin digestion, and by indirect immunofluorescent staining. CRSBP-1 appeared to form complexes with proteolytically processed forms (generated at and/or after the trans-Golgi network) of the v-sis gene product and with a approximately 140-kDa proteolytically cleaved form of the platelet-derived growth factor (PDGF) beta-type receptor, as demonstrated by metabolic labeling and co-immunoprecipitation. CRSBP-1, like the v-sis gene product and PDGF beta-type receptor, underwent rapid turnover which was blocked in the presence of 100 microM suramin. In normal and other transformed NIH 3T3 cells, CRSBP-1 was relatively stable and did not undergo rapid turnover and internalization/recycling at the cell surface. These results suggest that in SSV-NIH 3T3 cells, CRSBP-1 interacts with and forms ternary and binary complexes with the newly synthesized v-sis gene product and PDGF beta-type receptor at the trans-Golgi network and that the stable binary (CRSBP-1.v-sis gene product) complex is transported to the cell surface where it presents the v-sis gene product to unoccupied PDGF beta-type receptors during internalization/recycling.


Subject(s)
Cell Transformation, Viral , Membrane Proteins/metabolism , Receptors, Platelet-Derived Growth Factor/metabolism , Retroviridae Proteins, Oncogenic/metabolism , Sarcoma Virus, Woolly Monkey/metabolism , 3T3 Cells , Animals , Fluorescent Antibody Technique, Indirect , Mice , Oncogene Proteins v-sis , Rabbits , Receptor, Platelet-Derived Growth Factor beta , Suramin/metabolism , Surface Properties , Trypsin/metabolism
15.
J Virol ; 72(12): 9453-8, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9811678

ABSTRACT

We have sequenced the envelope genes from each of the five members of the gibbon ape leukemia virus (GALV) family of type C retroviruses. Four of the GALVs, including GALV strain SEATO (GALV-S), were originally isolated from gibbon apes, whereas the fifth member of this family, simian sarcoma-associated virus (SSAV), was isolated from a woolly monkey and shares 78% amino acid identity with GALV-S. To determine whether these viruses have identical host ranges, we evaluated the susceptibility of several cell lines to either GALV-S or SSAV infection. GALV-S and SSAV have the same host range with the exception of Chinese hamster lung E36 cells, which are susceptible to GALV-S but not SSAV. We used retroviral vectors that differ only in their envelope composition (e.g., they contain either SSAV or GALV-S envelope protein) to show that the envelope of SSAV restricts entry into E36 cells. Although unable to infect E36 cells, SSAV infects GALV-resistant murine cells expressing the E36-derived viral receptor, HaPit2. These results suggest that the receptors present on E36 cells function for SSAV. We have constructed several vectors containing GALV-S/SSAV chimeric envelope proteins to map the region of the SSAV envelope that blocks infection of E36 cells. Vectors bearing chimeric envelopes comprised of the N-terminal region of the GALV-S SU protein and the C-terminal region of SSAV infect E36 cells, whereas vectors containing the N-terminal portion of the SSAV SU protein and C-terminal portion of GALV-S fail to infect E36 cells. This finding indicates that the region of the SSAV envelope protein responsible for restricting SSAV infection of E36 cells lies within its amino-terminal region.


Subject(s)
Leukemia Virus, Gibbon Ape/pathogenicity , Receptors, Virus/physiology , Sarcoma Virus, Woolly Monkey/pathogenicity , Amino Acid Sequence , Animals , Cell Line , Cricetinae , Cricetulus , DNA, Viral/genetics , DNA, Viral/isolation & purification , Gene Products, env/chemistry , Gene Products, env/genetics , Gene Products, env/physiology , Genes, env , Genetic Vectors , Helper Viruses/pathogenicity , Leukemia Virus, Gibbon Ape/genetics , Mice , Molecular Sequence Data , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Sarcoma Virus, Woolly Monkey/genetics , Sequence Homology, Amino Acid , Virulence/genetics
18.
Endocrine ; 7(1): 119-24, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9449047

ABSTRACT

The authors have previously shown that the type 1 insulin-like growth factor receptor (IGF-1R) is decreased in the transformation from benign to malignant human prostate epithelial cells in vivo. Further, in a well-described human SV40-T immortalized human epithelial cell system beginning with the immortalized, but rarely tumorigenic P69SV40-T cell line, to the highly tumorigenic and metastatic M12 subline, there is a similar decrease in IGF-1R number from 2.0 x 10(4) receptors per cell to 1.1 x 10(3) receptors per cell. When the IGF-1R was reexpressed in the M12 subline using a retroviral expression vector, M12-LISN, to a receptor number similar to that of the P69SV40-T parental cell line, the authors demonstrated a marked decrease in colony formation in soft agar in the M12-LISN cells vs the M12 control cells (p < or = 0.01), and a decrease in vivo tumor growth and metastases when injected either subcutaneously or an intraprostatic location (p < or = 0.01). This decrease in tumor volume was not because of a decrease in proliferative capacity, but was associated with an increase in apoptosis in baseline cultures and in response to the apoptotic-inducing agents 6-hydroxyurea, retinoic acid, and transforming growth factor beta 1.


Subject(s)
Antigens, Polyomavirus Transforming , Apoptosis/physiology , Cell Transformation, Neoplastic/metabolism , Epithelial Cells/metabolism , Prostatic Neoplasms/metabolism , Receptor, IGF Type 1/genetics , Sarcoma Virus, Woolly Monkey/chemistry , Animals , Apoptosis/drug effects , Cell Line, Transformed , Epithelial Cells/pathology , Epithelial Cells/virology , Humans , Male , Mice , Mice, Nude , Phenotype , Prostatic Neoplasms/virology , Tumor Cells, Cultured
19.
J Virol ; 67(11): 6737-41, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8411376

ABSTRACT

The three type C retroviruses, gibbon ape leukemia virus (GALV), simian sarcoma-associated virus (SSAV), and feline leukemia virus subgroup B (FeLV-B), infect human cells by interacting with the same cell surface receptor, GLVR1. Using LacZ retroviral pseudotypes and murine cells transfected with mutant GLVR1 expression vectors, we show that the same 9-amino-acid region of human GLVR1 is critical for infection by the three viruses. Rat cells were not susceptible to infection by LacZ (FeLV-B) pseudotypes because of a block at the receptor level. We found multiple amino acid differences from human GLVR1 in the 9-amino-acid critical region of rat GLVR1. Expression of a human-rat chimeric GLVR1 in murine cells demonstrated that rat GLVR1 could function as a receptor for GALV and SSAV but not for FeLV-B. Substitution of human GLVR1 amino acids in the critical region of rat GLVR1 identified three amino acids as responsible for resistance to FeLV-B infection; two of these affect SSAV infection, but none affects GALV infection.


Subject(s)
Leukemia Virus, Feline/growth & development , Leukemia Virus, Gibbon Ape/growth & development , Receptors, Virus/genetics , Sarcoma Virus, Woolly Monkey/growth & development , Amino Acid Sequence , Animals , DNA Mutational Analysis , Humans , Mice , Molecular Sequence Data , Mutation , Rats , Receptors, Virus/chemistry , Recombinant Fusion Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid , Structure-Activity Relationship
20.
J Cell Biol ; 118(5): 1057-70, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1324943

ABSTRACT

An important question regarding autocrine transformation by v-sis is whether intracellularly activated PDGF receptors are sufficient to transform cells or whether activated receptor-ligand complexes are required at the cell surface. We have addressed this question by inhibiting cell surface transport of a membrane-anchored v-sis protein utilizing the ER retention signal of the adenoviral transmembrane protein E3/19K. A v-sis fusion protein containing this signal was retained within the cell and not transported to the cell surface as confirmed by immunofluorescent localization experiments. Also, proteolytic maturation of this protein was suppressed, indicating inefficient transport to post-Golgi compartments of the secretory pathway. When compared with v-sis proteins lacking a functional retention signal, the ER-retained protein showed a diminished ability to transform NIH 3T3 cells, as measured by the number and size of foci formed. In newly established cell lines, the ER-retained protein did not down-regulate PDGF receptors. However, continued passage of these cells selected for a fully transformed phenotype exhibiting downregulated PDGF receptors and proteolytically processed v-sis protein. These results indicate that productive autocrine interactions occur in a post-ER compartment of the secretory pathway. Transport of v-sis protein beyond the Golgi correlated with acquisition of the transformed phenotype. Furthermore, suramin treatment reversed transformation and upregulated the expression of cell surface PDGF receptors, suggesting an important role for receptor-ligand complexes localized to the cell surface.


Subject(s)
Cell Membrane/metabolism , Cell Transformation, Neoplastic , Endoplasmic Reticulum/metabolism , Retroviridae Proteins, Oncogenic/metabolism , Signal Transduction , 3T3 Cells , Amino Acid Sequence , Animals , Base Sequence , Cell Transformation, Neoplastic/drug effects , Down-Regulation , Golgi Apparatus/metabolism , Mice , Molecular Sequence Data , Oncogene Proteins v-sis , Receptors, Cell Surface/metabolism , Receptors, Platelet-Derived Growth Factor , Sarcoma Virus, Woolly Monkey , Suramin/pharmacology , Up-Regulation
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