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Ramana CV, Das B. Regulation of early growth response-1 (Egr-1) gene expression by Stat1-independent type I interferon signaling and respiratory viruses. COMPUTATIONAL AND MATHEMATICAL BIOPHYSICS 2021. [DOI: 10.1515/cmb-2020-0129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Respiratory virus infection is one of the leading causes of death in the world. Activation of the Jak-Stat pathway by Interferon-alpha/beta (IFN-α/β) in lung epithelial cells is critical for innate immunity to respiratory viruses. Transcriptional factor profiling in the transcriptome and RNA analysis revealed that Early growth response-1 (EGR1/Egr-1) was rapidly induced by IFN-α/β and Toll-like receptor (TLR) ligands in multiple cell types. Studies in mutant cell lines lacking components of the interferon-stimulated gene factor complex (ISGF-3) revealed that IFN-β induction of Egr-1 was independent of Stat1, Stat2, or Irf9. Activation of the Mek/Erk-1/2 pathway was implicated in the rapid induction of Egr-1 by IFN-β in serum-starved mouse lung epithelial cells. Interrogation of multiple microarray datasets revealed that respiratory viruses including coronaviruses induced IFN-β and regulated Egr-1 expression in human lung cell lines. Furthermore, bioinformatic analysis revealed that type I interferon-stimulated genes and Egr-1 inducible genes including transcription factors, mediators of cell growth, and chemokines were differentially regulated in the human lung cell lines after coronavirus infection, and in the lung biopsies of COVID-19 patients.
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Affiliation(s)
- Chilakamarti V. Ramana
- Department of Medicine , Dartmouth-Hitchcock Medical Center , Lebanon , NH 03766, USA ; Department of Stem Cell and Infectious Diseases , KaviKrishna Laboratory , Guwahati Biotech Park, Indian Institute of Technology , Guwahati , India ; Thoreau Laboratory for Global Health , University of Massachusetts , Lowell, MA 01854, USA
| | - Bikul Das
- Department of Stem Cell and Infectious Diseases , KaviKrishna Laboratory , Guwahati Biotech Park, Indian Institute of Technology , Guwahati , India ; Thoreau Laboratory for Global Health , University of Massachusetts , Lowell, MA 01854, USA
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Nicholas DA, Zhang K, Hung C, Glasgow S, Aruni AW, Unternaehrer J, Payne KJ, Langridge WHR, De Leon M. Palmitic acid is a toll-like receptor 4 ligand that induces human dendritic cell secretion of IL-1β. PLoS One 2017; 12:e0176793. [PMID: 28463985 PMCID: PMC5413048 DOI: 10.1371/journal.pone.0176793] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/17/2017] [Indexed: 01/22/2023] Open
Abstract
Palmitic acid (PA) and other saturated fatty acids are known to stimulate pro-inflammatory responses in human immune cells via Toll-like receptor 4 (TLR4). However, the molecular mechanism responsible for fatty acid stimulation of TLR4 remains unknown. Here, we demonstrate that PA functions as a ligand for TLR4 on human monocyte derived dendritic cells (MoDCs). Hydrophobicity protein modeling indicated PA can associate with the hydrophobic binding pocket of TLR4 adaptor protein MD-2. Isothermal titration calorimetry quantified heat absorption that occurred during PA titration into TLR4/MD2, indicating that PA binds to TLR4/MD2. Treatment of human MoDCs with PA resulted in endocytosis of TLR4, further supporting the function of PA as a TLR4 agonist. In addition, PA stimulated DC maturation and activation based on the upregulation of DC costimulatory factors CD86 and CD83. Further experiments showed that PA induced TLR4 dependent secretion of the pro-inflammatory cytokine IL-1β. Lastly, our experimental data show that PA stimulation of NF-κB canonical pathway activation is regulated by TLR4 signaling and that reactive oxygen species may be important in upregulating this pro-inflammatory response. Our experiments demonstrate for the first time that PA activation of TLR4 occurs in response to direct molecular interactions between PA and MD-2. In summary, our findings suggest a likely molecular mechanism for PA induction of pro-inflammatory immune responses in human dendritic cells expressing TLR4.
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Affiliation(s)
- Dequina A. Nicholas
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Kangling Zhang
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Christopher Hung
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Shane Glasgow
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Aruni Wilson Aruni
- Department of Basic Sciences, Division of Microbiology and Molecular Genetics, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Juli Unternaehrer
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Kimberly J. Payne
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Department of Anatomy and Physiology, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - William H. R. Langridge
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Marino De Leon
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Department of Basic Sciences, Division of Physiology, Loma Linda University School Medicine, Loma Linda, California, United States of America
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Schmidt SV, Seibert S, Walch-Rückheim B, Vicinus B, Kamionka EM, Pahne-Zeppenfeld J, Solomayer EF, Kim YJ, Bohle RM, Smola S. RIPK3 expression in cervical cancer cells is required for PolyIC-induced necroptosis, IL-1α release, and efficient paracrine dendritic cell activation. Oncotarget 2016; 6:8635-47. [PMID: 25888634 PMCID: PMC4496172 DOI: 10.18632/oncotarget.3249] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/28/2015] [Indexed: 11/25/2022] Open
Abstract
Previous studies have shown that cervical cancer cells only release low levels of pro-inflammatory cytokines owing to infection with human papillomaviruses. This results in low immunogenicity of the cancer cells. The viral dsRNA analog PolyIC has been suggested as a promising adjuvant for cervical cancer immunotherapy. However, little is known about the molecular requirements resulting in successful immune activation. Here, we demonstrate that stimulation of cervical cancer cells with PolyIC induced necroptotic cell death, which was strictly dependent on the expression of the receptor-interacting protein kinase RIPK3. Necroptotic cancer cells released interleukin-1α (IL-1α), which was required for powerful activation of dendritic cells (DC) to produce IL-12, a cytokine critical for anti-tumor responses. Again both, IL-1α release and DC activation, were strictly dependent on RIPK3 expression in the tumor cells. Of note, our in situ analyses revealed heterogeneous RIPK3 expression patterns in cervical squamous cell carcinomas and adenocarcinomas. In summary, our study identified a novel RIPK3-dependent mechanism that explains how PolyIC-treatment of cervical cancer cells leads to potent DC activation. Our findings suggest that the RIPK3 expression status in cervical cancer cells might critically influence the outcome of PolyIC-based immunotherapeutic approaches and should therefore be assessed prior to immunotherapy.
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Affiliation(s)
- Susanne V Schmidt
- Center for Molecular Medicine Cologne and Institute of Virology, University of Cologne, Germany
| | - Stefanie Seibert
- Institute of Virology, Saarland University, Homburg/Saar, Germany
| | | | - Benjamin Vicinus
- Institute of Virology, Saarland University, Homburg/Saar, Germany
| | | | | | | | - Yoo-Jin Kim
- Department of Pathology, Saarland University, Homburg/Saar, Germany
| | - Rainer M Bohle
- Department of Pathology, Saarland University, Homburg/Saar, Germany
| | - Sigrun Smola
- Center for Molecular Medicine Cologne and Institute of Virology, University of Cologne, Germany.,Institute of Virology, Saarland University, Homburg/Saar, Germany
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4
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Expression and functional analysis of Toll-like receptor 4 in human cervical carcinoma. J Membr Biol 2014; 247:591-9. [PMID: 24878539 DOI: 10.1007/s00232-014-9675-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 05/09/2014] [Indexed: 10/25/2022]
Abstract
Toll-like receptors are expressed in human immune cells and many tumors, but the role of toll-like receptor 4 (TLR4) in the development of tumors is controversial. We demonstrated the expression, distribution, and functional activity of TLR4 in tissues of normal cervix, cervical intraepithelial neoplasia (CIN), invasion cervical cancers (ICC), and different human papillomavirus (HPV)-infected cervical cancer cells. The results showed that TLR4 expression was in accordance with the histopathological grade: higher in ICC than in CIN, and low in normal cervical tissues and malignant cervical stroma. Expression was higher in SiHa (HPV16+) than in HeLa (HPV18+) cells, but was not observed in C33A (HPV-) cells. After treatment with its agonist, lipopolysaccharide (LPS), the expression levels of TLR4 was increased and apoptosis resistance was induced in SiHa cells, but not in HeLa or C33A cells. Meanwhile, LPS treatment did not alter the cell cycle distribution in SiHa cells. The mechanism of apoptosis resistance may be related to HPV16 infection and not correlated with the cell cycle distribution. Targeting TLR4 in combination with traditional drug treatment may serve as a novel strategy for more effectively killing cancer cells.
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Jin L, Sturgis EM, Zhang Y, Huang Z, Song X, Li C, Wei Q, Li G. Association of tumor necrosis factor-alpha promoter variants with risk of HPV-associated oral squamous cell carcinoma. Mol Cancer 2013; 12:80. [PMID: 23870134 PMCID: PMC3725173 DOI: 10.1186/1476-4598-12-80] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 07/11/2013] [Indexed: 11/10/2022] Open
Abstract
Background Tumor necrosis factor alpha (TNF-α) plays an important role in inflammation, immunity, and defense against infection and clearance of human papillomavirus (HPV). Thus, genetic variants may modulate individual susceptibility to HPV-associated oral squamous cell carcinoma (OSCC). Methods In this study we genotyped four common single nucleotide polymorphisms (SNPs) in the TNF-α promoter [ −308G > A(rs1800629), -857C > T (rs1799724), -863C > A (rs1800630), and -1031T > C (rs1799964)] and determined HPV16 serology in 325 OSCC cases and 335 matched controls and tumor HPV status in 176 squamous cell carcinomas of the oropharynx (SCCOP) patients. Univariate and multivariable logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Results We found that HPV16 seropositivity alone was associated with an increased risk of OSCC (OR, 3.1; 95% CI, 2.1–4.6), and such risk of HPV16-associated OSCC was modified by each SNP. Patients with both HPV16 seropositivity and variant genotypes for each SNP had the highest risk when using patients with HPV16 seronegativity and a wild-type genotype as a comparison group. Moreover, similar results were observed for the combined risk genotypes of four variants and all such significant associations were more pronounced in several subgroups, particularly in SCCOP patients and never smokers. Notably, the combined risk genotypes of four variants were also significantly associated with tumor HPV-positive SCCOP. Conclusion Taken together, these results suggest that TNF-α SNPs may individually or, more likely, jointly affect individual susceptibility to HPV16-associated OSCC, particularly SCCOP and never smokers. Validation of our findings is warranted.
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Affiliation(s)
- Lei Jin
- Department of Stomatology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
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6
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Henken FE, De-Castro Arce J, Rösl F, Bosch L, Meijer CJLM, Snijders PJF, Steenbergen RDM. The functional role of Notch signaling in HPV-mediated transformation is dose-dependent and linked to AP-1 alterations. Cell Oncol (Dordr) 2012; 35:77-84. [PMID: 22271085 PMCID: PMC3306567 DOI: 10.1007/s13402-011-0062-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/18/2011] [Indexed: 12/11/2022] Open
Abstract
Background The role of Notch signaling in HPV-mediated transformation has been a long standing debate, as both tumor suppressive and oncogenic properties have been described. We examined whether the dual findings in literature may be explained by gene dosage effects and determined the relation with AP-1, a downstream target of Notch. Methods SiHa cervical cancer cells were transfected with two doses of intracellular active Notch. Non-tumorigenic HPV16-immortalized keratinocytes (FK16A) were transfected with Fra1 specific siRNAs and non-targeting controls. Transfectants were analysed for Notch, Hes, cJun, cFos and Fra1 mRNA expression, Notch pathway activation using luciferase assays, cell viability using MTT assays, anchorage independent growth, AP-1 activity and/or AP-1 complex composition using EMSA. Results In SiHa cells two activation states of Notch signaling pathway were obtained. Moderate Notch activation contributed to increased viability and anchorage independent growth, whereas high level Notch activation decreased anchorage independent growth. The shift in phenotypical outcome was correlated to altered AP-1 activity and complex composition. Moderate Notch expression led to an increased AP-1 transcriptional activity and DNA binding activity, but did not affect complex composition. High levels of Notch additionally led to a change in AP-1 complex composition, from cJun/cFos to cJun/Fra1 dimers, which is exemplary for non-tumorigenic HPV-immortalized cell lines. Conversely, silencing of Fra1 in non-tumorigenic HPV16-immortalized keratinocytes, leading to an enrichment of cJun/cFos dimers, was accompanied with increased colony formation. Conclusion The functional role of Notch in HPV-mediated transformation is dosage dependent and correlated to a change in AP-1.
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Affiliation(s)
- Florianne E Henken
- Department of Pathology, Unit of Molecular Pathology, VU University Medical Center, Amsterdam, The Netherlands
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7
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DeCarlo CA, Severini A, Edler L, Escott NG, Lambert PF, Ulanova M, Zehbe I. IFN-κ, a novel type I IFN, is undetectable in HPV-positive human cervical keratinocytes. J Transl Med 2010; 90:1482-91. [PMID: 20479716 DOI: 10.1038/labinvest.2010.95] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Interferons (IFNs) are expressed by many cell types and play a pivotal role in the generation of immune responses against viral infections. IFN-κ, a novel type I IFN, displays a tight tropism for keratinocytes and specific lymphoid populations and exhibits functional similarities with other type I IFNs. The human papillomavirus (HPV), the etiological agent for cervical cancer, infects keratinocytes of the uterine cervix and has been shown to directly inhibit the IFN pathway. We evaluated IFN-κ, -β, and -γ gene expression in HPV-negative normal and HPV-positive pre-malignant and malignant ex vivo cervical tissue covering the entire spectrum of cervical disease. Quantitative real-time polymerase chain reaction and methods previously optimized for detecting low-expressing genes in cervical tissue were used. In contrast to IFN-β and -γ, IFN-κ mRNA prevalence and levels were unexpectedly higher in diseased compared with normal whole cervical tissue with highest levels observed in invasive carcinoma tissue. Strikingly, laser capture microdissection revealed an absence of IFN-κ mRNA in diseased epithelium, whereas stromal IFN-κ was found exclusively in diseased tissue. IFN-γ and IFN-β were likewise found to be upregulated in diseased cervical stroma. Immunofluorescence supports the involvement of monocytes and dendritic cells in the stromal induction of IFNs in diseased tissue. Further, using three-dimensional raft cultures in which the viral life cycle can be mimicked, human keratinocytes transfected with full-length HPV16 displayed a significant decrease in IFN-κ mRNA compared with non-transfected human keratinocytes. Altogether, these findings show that IFN-κ is down-regulated in cervical keratinocytes harboring HPV, which may be a contributing factor in the progression of a cervical lesion.
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Affiliation(s)
- Correne A DeCarlo
- Thunder Bay Regional Research Institute, Probe Development and Biomarker Exploration, Thunder Bay, ON, Canada
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8
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Hacke K, Rincon-Orozco B, Buchwalter G, Siehler SY, Wasylyk B, Wiesmüller L, Rösl F. Regulation of MCP-1 chemokine transcription by p53. Mol Cancer 2010; 9:82. [PMID: 20406462 PMCID: PMC2864217 DOI: 10.1186/1476-4598-9-82] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Accepted: 04/20/2010] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Our previous studies showed that the expression of the monocyte-chemoattractant protein (MCP)-1, a chemokine, which triggers the infiltration and activation of cells of the monocyte-macrophage lineage, is abrogated in human papillomavirus (HPV)-positive premalignant and malignant cells. In silico analysis of the MCP-1 upstream region proposed a putative p53 binding side about 2.5 kb upstream of the transcriptional start. The aim of this study is to monitor a physiological role of p53 in this process. RESULTS The proposed p53 binding side could be confirmed in vitro by electrophoretic-mobility-shift assays and in vivo by chromatin immunoprecipitation. Moreover, the availability of p53 is apparently important for chemokine regulation, since TNF-alpha can induce MCP-1 only in human keratinocytes expressing the viral oncoprotein E7, but not in HPV16 E6 positive cells, where p53 becomes degraded. A general physiological role of p53 in MCP-1 regulation was further substantiated in HPV-negative cells harboring a temperature-sensitive mutant of p53 and in Li-Fraumeni cells, carrying a germ-line mutation of p53. In both cases, non-functional p53 leads to diminished MCP-1 transcription upon TNF-alpha treatment. In addition, siRNA directed against p53 decreased MCP-1 transcription after TNF-alpha addition, directly confirming a crosstalk between p53 and MCP-1. CONCLUSION These data support the concept that p53 inactivation during carcinogenesis also affects immune surveillance by interfering with chemokine expression and in turn communication with cells of the immunological compartment.
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Affiliation(s)
- Katrin Hacke
- Deutsches Krebsforschungszentrum, Forschungsschwerpunkt Infektion und Krebs, Abteilung Virale Transformationsmechanismen, Heidelberg, Germany
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Lace MJ, Anson JR, Haugen TH, Turek LP. Interferon regulatory factor (IRF)-2 activates the HPV-16 E6-E7 promoter in keratinocytes. Virology 2010; 399:270-9. [PMID: 20129639 DOI: 10.1016/j.virol.2009.12.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Revised: 11/17/2009] [Accepted: 12/17/2009] [Indexed: 11/30/2022]
Abstract
Interferon regulatory factors (IRFs) are critical mediators of gene expression, cell growth and immune responses. We previously demonstrated that interferon (IFN) induction of early viral transcription and replication in several mucosal HPVs requires IRF-1 binding to a conserved interferon response element (IRE). Here we show that the IRF-2 protein serves as a baseline transactivator of the HPV-16 major early promoter, P97. Cotransfections in IRF knockout cells confirmed that basal HPV-16 promoter activity was supported by both IRF-1 and IRF-2 complexes interacting with the promoter-proximal IRE in a dose-dependent manner. Furthermore, HPV-16 E7 expression downregulates the IRF-2 promoter, thus linking IRF-2 levels to viral transforming gene expression through a negative feedback mechanism. Taken together, these observations reveal a complex viral strategy utilizing multiple signal transduction pathways during the establishment and maintenance of HPV persistence.
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Affiliation(s)
- Michael J Lace
- Department of Pathology, VAMC, University of Iowa, Iowa City, IA 52242, USA.
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10
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Rincon-Orozco B, Halec G, Rosenberger S, Muschik D, Nindl I, Bachmann A, Ritter TM, Dondog B, Ly R, Bosch FX, Zawatzky R, Rösl F. Epigenetic silencing of interferon-kappa in human papillomavirus type 16-positive cells. Cancer Res 2009; 69:8718-25. [PMID: 19887612 DOI: 10.1158/0008-5472.can-09-0550] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have investigated interferon-kappa (IFN-kappa) regulation in the context of human papillomavirus (HPV)-induced carcinogenesis using primary human foreskin keratinocytes (HFK), immortalized HFKs encoding individual oncoproteins of HPV16 (E6, E7, and E6/E7), and cervical carcinoma cells. Here, IFN-kappa was suppressed in the presence of E6, whereas its expression was not affected in HFKs or E7-immortalized HFKs. Transcription could be reactivated after DNA demethylation but was decreased again upon drug removal. Partial reactivation could also be accomplished when E6 was knocked down, suggesting a contribution of E6 in IFN-kappa de novo methylation. We identified a single CpG island near the transcriptional start site as being involved in selective IFN-kappa expression. To prove the functional relevance of IFN-kappa in building up an antiviral response, IFN-kappa was ectopically expressed in cervical carcinoma cells where protection against vesicular stomatitis virus-mediated cytolysis could be achieved. Reconstitution of IFN-kappa was accompanied by an increase of p53, MxA, and IFN-regulatory factors, which was reversed by knocking down either IFN-kappa or p53 by small interfering RNA. This suggests the existence of a positive feedback loop between IFN-kappa, p53, and components of IFN signaling pathway to maintain an antiviral state. Our in vitro findings were further corroborated in biopsy samples of cervical cancer patients, in which IFN-kappa was also downregulated when compared with normal donor tissue. This is the first report showing an epigenetic silencing of type I IFN after HPV16 oncogene expression and revealing a novel strategy on how high-risk HPVs can abolish the innate immune response in their genuine host cells.
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Affiliation(s)
- Bladimiro Rincon-Orozco
- Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Universität Heidelberg, Heidelberg, Germany
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11
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Termini L, Boccardo E, Esteves GH, Hirata R, Martins WK, Colo AEL, Neves EJ, Villa LL, Reis LFL. Characterization of global transcription profile of normal and HPV-immortalized keratinocytes and their response to TNF treatment. BMC Med Genomics 2008; 1:29. [PMID: 18588690 PMCID: PMC2459201 DOI: 10.1186/1755-8794-1-29] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Accepted: 06/27/2008] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Persistent infection by high risk HPV types (e.g. HPV-16, -18, -31, and -45) is the main risk factor for development of cervical intraepithelial neoplasia and cervical cancer. Tumor necrosis factor (TNF) is a key mediator of epithelial cell inflammatory response and exerts a potent cytostatic effect on normal or HPV16, but not on HPV18 immortalized keratinocytes. Moreover, several cervical carcinoma-derived cell lines are resistant to TNF anti-proliferative effect suggesting that the acquisition of TNF-resistance may constitute an important step in HPV-mediated carcinogenesis. In the present study, we compared the gene expression profiles of normal and HPV16 or 18 immortalized human keratinocytes before and after treatment with TNF for 3 or 60 hours. METHODS In this study, we determined the transcriptional changes 3 and 60 hours after TNF treatment of normal, HPV16 and HPV18 immortalized keratinocytes by microarray analysis. The expression pattern of two genes observed by microarray was confirmed by Northern Blot. NF-kappaB activation was also determined by electrophoretic mobility shift assay (EMSA) using specific oligonucleotides and nuclear protein extracts. RESULTS We observed the differential expression of a common set of genes in two TNF-sensitive cell lines that differs from those modulated in TNF-resistant ones. This information was used to define genes whose differential expression could be associated with the differential response to TNF, such as: KLK7 (kallikrein 7), SOD2 (superoxide dismutase 2), 100P (S100 calcium binding protein P), PI3 (protease inhibitor 3, skin-derived), CSTA (cystatin A), RARRES1 (retinoic acid receptor responder 1), and LXN (latexin). The differential expression of the KLK7 and SOD2 transcripts was confirmed by Northern blot. Moreover, we observed that SOD2 expression correlates with the differential NF-kappaB activation exhibited by TNF-sensitive and TNF-resistant cells. CONCLUSION This is the first in depth analysis of the differential effect of TNF on normal and HPV16 or HPV18 immortalized keratinocytes. Our findings may be useful for the identification of genes involved in TNF resistance acquisition and candidate genes which deregulated expression may be associated with cervical disease establishment and/or progression.
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Affiliation(s)
- Lara Termini
- Ludwig Institute for Cancer Research, São Paulo, Brazil
- Hospital do Câncer A. C. Camargo, São Paulo, Brazil
| | | | - Gustavo H Esteves
- Instituto de Matemática e Estatística da Universidade de São Paulo, São Paulo, Brazil
| | - Roberto Hirata
- Instituto de Matemática e Estatística da Universidade de São Paulo, São Paulo, Brazil
| | - Waleska K Martins
- Ludwig Institute for Cancer Research, São Paulo, Brazil
- Hospital do Câncer A. C. Camargo, São Paulo, Brazil
| | - Anna Estela L Colo
- Ludwig Institute for Cancer Research, São Paulo, Brazil
- Hospital do Câncer A. C. Camargo, São Paulo, Brazil
| | - E Jordão Neves
- Instituto de Matemática e Estatística da Universidade de São Paulo, São Paulo, Brazil
| | | | - Luiz FL Reis
- Ludwig Institute for Cancer Research, São Paulo, Brazil
- Hospital do Câncer A. C. Camargo, São Paulo, Brazil
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12
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Li H, Gade P, Xiao W, Kalvakolanu DV. The interferon signaling network and transcription factor C/EBP-beta. Cell Mol Immunol 2007; 4:407-418. [PMID: 18163952 PMCID: PMC2782719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
Cytokines like interferons (IFNs) play a central role in regulating innate and specific immunities against the pathogens and neoplastic cells. A number of signaling pathways are induced in response to IFN in various cells. One classic mechanism employed by IFNs is the JAK-STAT signaling pathway for inducing cellular responses. Here we describe the non-STAT pathways that participate in IFN-induced responses. In particular, we will focus on the role played by transcription factor C/EBP-beta in mediating these responses.
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Affiliation(s)
- Hui Li
- Department of Microbiology & Immunology, Greenebaum Cancer Center, University of Maryland School of Medicine, 660 W. Redwood Street, Baltimore, MD 21201, USA
- Institute of Medical Virology, Wuhan University, Wuhan, China
| | - Padmaja Gade
- Department of Microbiology & Immunology, Greenebaum Cancer Center, University of Maryland School of Medicine, 660 W. Redwood Street, Baltimore, MD 21201, USA
| | - Weihua Xiao
- School of Life Sciences, University of Science and Technology, Hefei, Anhui, China
| | - Dhan V. Kalvakolanu
- Department of Microbiology & Immunology, Greenebaum Cancer Center, University of Maryland School of Medicine, 660 W. Redwood Street, Baltimore, MD 21201, USA
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13
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Bachmann A, Zawatzky R, Rösl F. Genetic redundancy in human cervical carcinoma cells: identification of cells with "normal" properties. Int J Cancer 2007; 120:2119-26. [PMID: 17266037 DOI: 10.1002/ijc.22524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Although it is generally assumed that cancer arises from a singular cell, a tumor must be considered as a dynamic and emergent biological structure, whose organizing principle is determined by genetic and epigenetic modifications, occurring variably in response to microenvironmental selection conditions. As previously shown, HPV-positive cervical carcinoma cells have lost their ability to induce IFN-beta upon TNF-alpha treatment. However, regarding cancer as a non-linear system, which may, even in the absence of an apparent selection pressure, fluctuate between different "metastable" phenotypes, we demonstrate that TNF-alpha mediated IFN-beta induction is not irreversibly disturbed in all cells. Using the IFN-beta sensitive Encephalomyocarditis virus (EMCV) as a tool to monitor antiviral activity in long-term established malignant HeLa cells, rare IFN-beta expressing clones were rescued from a population of non-responsive and EMCV-sensitive cells. Antiviral activity was mediated by the re-expression of IRF-1 and p48 (IRF-9), both key regulatory molecules normally found to be suppressed in cervical carcinoma cells. Upon inoculating of selected clones into immunocompromised animals, a reduced or even an absence of tumorigenicity of initially highly malignant cells could be discerned. These data indicate that both the absence of interferon signaling and the ability to form tumors were reversed in a minority of cells. We provide a paradigm for the existence of innate genetic redundancy mechanisms, where a particular phenotype persists and can be isolated without application of drugs generally changing the epigenetic context.
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Affiliation(s)
- Anastasia Bachmann
- Forschungsschwerpunkt Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 242, 69120 Heidelberg, Federal Republic of Germany
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14
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Nafz J, De-Castro Arce J, Fleig V, Patzelt A, Mazurek S, Rösl F. Interference with energy metabolism by 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside induces HPV suppression in cervical carcinoma cells and apoptosis in the absence of LKB1. Biochem J 2007; 403:501-10. [PMID: 17212587 PMCID: PMC1876364 DOI: 10.1042/bj20061053] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Carcinogenesis is a dynamic and stepwise process, which is accompanied by a variety of somatic and epigenetic alterations in response to a changing microenvironment. Hypoxic conditions will select for cells that have adjusted their metabolic profile and can maintain proliferation by successfully competing for scarce nutritional and oxygen resources. In the present study we have investigated the effects of energy depletion in the context of HPV (human papillomavirus)-induced pathogenesis. We show that cervical carcinoma cell lines are susceptible to undergoing either growth arrest or cell death under conditions of metabolic stress induced by AICAR (5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside), a known activator of the AMPK (AMP-activated protein kinase). Our results reveal that AICAR treatment leads to a reduced binding affinity of the transcription factor AP-1 (activator protein-1) and in turn to a selective suppression of HPV transcription. Moreover, the outcome of AICAR on proliferation and survival was dependent on p53 activation and the presence of LKB1, the major upstream kinase of AMPK. Using non-malignant LKB1-expressing somatic cell hybrids, which lose expression after tumorigenic segregation, as well as small interfering RNA LKB1 knockdown approaches, we could further demonstrate that expression of LKB1 protects cells from cytotoxicity induced by agents which modulate the ATP/AMP ratio. Since simulation of low energy status can selectively eradicate LKB1-negative cervical carcinoma cells, AICAR may represent a novel drug in the treatment of cervical cancer.
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Affiliation(s)
- Julia Nafz
- *Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Heidelberg 69120, Germany
| | - Johanna De-Castro Arce
- *Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Heidelberg 69120, Germany
| | - Verena Fleig
- *Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Heidelberg 69120, Germany
| | - Andrea Patzelt
- *Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Heidelberg 69120, Germany
| | - Sybille Mazurek
- †Institut für Biochemie und Endokrinologie, Fachbereich Veterinärmedizin, Universität Giessen, Giessen 35392, Germany
| | - Frank Rösl
- *Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Heidelberg 69120, Germany
- To whom correspondence should be addressed (email )
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Ferreira PM, Catarino R, Pereira D, Matos A, Pinto D, Coelho A, Lopes C, Medeiros R. Cervical cancer and CYP2E1 polymorphisms: implications for molecular epidemiology. Eur J Clin Pharmacol 2005; 62:15-21. [PMID: 16372174 DOI: 10.1007/s00228-005-0066-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Accepted: 11/11/2005] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Besides human papillomavirus (HPV) infection, several cofactors are considered important for the development of cervical cancer (CC). Among these, tobacco smoke, other sexually transmitted diseases, inflammation and nutritional factors have been intensively described. CYP2E1 polymorphisms have been associated with the metabolization of several carcinogens, some of them considered risk factors for CC development, such as tobacco smoke. The aim of this study was to evaluate the role of CYP2E1 polymorphisms in the susceptibility to cervical cancer in a Portuguese population. PATIENTS AND METHODS The genotypic analysis was performed with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methodology, using peripheral blood samples of 454 individuals: 122 presented invasive squamous cell carcinoma (ICC), 59 presented squamous intraepithelial lesions (SIL), and the control population was composed of 274 healthy individuals. RESULTS Concerning the DraI polymorphism, we observed a decreased risk for the development of squamous cervical lesions in the presence of the C allele [odds ratio (OR)=0.600; 0.378<OR<0.952; p=0.029]. In the stratification of the analysis according to the mean age, we observed an increased risk for the development of SIL, for women older than 39 years of age, in the presence of the D allele (OR=0.087; 0.012<OR<0.651; p=0.003). Regarding the RsaI polymorphism, we did not find any significant differences. CONCLUSION The decreased risk observed for the development of SIL and not ICC in the presence of the D allele may indicate that CYP2E1 interferes with the initial steps of the carcinogenic process, probably due to its involvement in the action of immunological mediators, expressed during cervical inflammation. These aspects may help to define new therapeutic strategies for chemoprevention.
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Affiliation(s)
- Paula M Ferreira
- Oncologia Molecular-Laboratórios, Instituto Português de Oncologia-Porto, Piso 4, Rua Dr António Bernardino de Almeida, 4200-072, Porto, Portugal
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Fernandes APM, Gonçalves MAG, Duarte G, Cunha FQ, Simões RT, Donadi EA. HPV16, HPV18, and HIV infection may influence cervical cytokine intralesional levels. Virology 2005; 334:294-8. [PMID: 15780879 DOI: 10.1016/j.virol.2005.01.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2004] [Revised: 11/19/2004] [Accepted: 01/26/2005] [Indexed: 10/25/2022]
Abstract
Infection with oncogenic human papillomavirus (HPV) is considered to be the major risk to cervical cancer. This study analyzed the influence of HPV infection on cytokine intralesional levels in cervical lesion in the presence or not of HIV infection. Cervical biopsies from 42 women were studied. HPV detection and typing were performed using amplified DNA hybridized with sequence-specific primers, and cytokine intralesional levels were detected using ELISA. HPV16+ biopsies exhibited increased IFN-gamma and IL-10 when compared to HPV16- (P = 0.03 and 0.04, respectively). HPV18+ biopsies exhibited decreased TNF-alpha (P = 0.009) and IFN- gamma (P = 0.01) when compared to HPV18-. In accordance to HIV status, HIV-/HPV16+ patients exhibited increased IFN-gamma when compared to those presenting HIV-/HPV16- (P = 0.007). HIV-/HPV18+ patients presented decreased IFN-gamma when compared to HIV-/HPV18- (P = 0.02). These results suggest that the presence of HPV16 infection may influence cervical lesion installation, and irrespective of HIV status, HPV18 infection may be more aggressive than HPV-16.
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Affiliation(s)
- Ana Paula M Fernandes
- Department of General and Specialized Nursing, School of Nursing of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, 14049-902 Ribeirão Preto, SP, Brazil
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17
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van Riggelen J, Buchwalter G, Soto U, De-Castro Arce J, zur Hausen H, Wasylyk B, Rösl F. Loss of Net as Repressor Leads to Constitutive Increased c-fos Transcription in Cervical Cancer Cells. J Biol Chem 2005; 280:3286-94. [PMID: 15548518 DOI: 10.1074/jbc.m409915200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have investigated the expression of c-fos in cervical carcinoma cells and in somatic cell hybrids derived therefrom. In malignant cells, c-fos was constitutively expressed even after serum starvation. Dissection of the c-fos promoter showed that expression was mainly controlled by the SRE motif, which was active in malignant cells, but repressed in their non-malignant counterparts. Constitutive SRE activity was not mediated by sustained mitogen-activated protein kinase activity but because of inefficient expression of the ternary complex factor Net, which was either very low or even barely discernible. Chromatin immunoprecipitation assays revealed that Net directly binds to the SRE nucleoprotein complex in non-tumorigenic cells, but not in malignant segregants. Small interfering RNA targeted against Net resulted in enhanced c-fos transcription, clearly illustrating its repressor function. Conversely, stable ectopic expression of Net in malignant cells negatively regulated endogenous c-fos, resulting in a disappearance of the c-Fos protein from the AP-1 transcription complex. These data indicate that loss of Net and constitutive c-fos expression appear to be a key event in the transformation of cervical cancer cells.
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Affiliation(s)
- Jan van Riggelen
- Angewandte Tumorvirologie, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
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18
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De-Castro Arce J, Soto U, van Riggelen J, Schwarz E, zur Hausen H, Rösl F. Ectopic expression of nonliganded retinoic acid receptor beta abrogates AP-1 activity by selective degradation of c-Jun in cervical carcinoma cells. J Biol Chem 2004; 279:45408-16. [PMID: 15308638 DOI: 10.1074/jbc.m401818200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Expression of the nuclear retinoic acid receptor beta2 (RARbeta2) gene is often disturbed in cervical carcinoma cells. One important mechanism by which RARbeta2 can exert growth inhibitory function is based on its ability to repress the AP-1 transcription factor in a ligand-dependent manner. Because less is known about the biological effects of RARbeta in the absence of ligand, the corresponding cDNA was stably introduced into HPV18-positive HeLa cervical carcinoma cells. In the present study we describe a novel mechanism by which AP-1 becomes inactivated. Constitutive expression of nonliganded RARbeta abrogated both AP-1 binding affinity and activity by a selective degradation of the c-Jun protein as major dimerization partner, without substitution by other members of the Jun family. Blockage of the proteasomal pathway completely rescued c-Jun and reconstituted the AP-1 function. Moreover, HeLa RARbeta2 clones treated either with tumor necrosis factor-alpha or transfected with a constitutive active upstream mitogen-activated protein kinase (MEKK1Delta) also resulted in c-Jun phosphorylation and restoration of AP-1 affinity and functionality similar to that found in nontransfected parental HeLa cells. These data revealed an important cross-talk between trans-repression of AP-1 and nonliganded RARbeta in human papillomavirus-positive cells. Because AP-1 activity was not irreversibly disturbed, but could be switched on through activation of the Jun N-terminal kinase pathway, a model for the transient activation of AP-1 even in the presence of RARbeta as repressor is suggested.
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Affiliation(s)
- Johanna De-Castro Arce
- Angewandte Tumorvirologie, Abteilung Virale Transformationsmechanismen, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
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Wagner TC, Velichko S, Chesney SK, Biroc S, Harde D, Vogel D, Croze E. Interferon receptor expression regulates the antiproliferative effects of interferons on cancer cells and solid tumors. Int J Cancer 2004; 111:32-42. [PMID: 15185340 DOI: 10.1002/ijc.20236] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In addition to antiviral effects, Type I interferons (IFN) have potent antiproliferative and immunomodulatory activities. Because of these properties IFNs have been evaluated as therapeutics for the treatment of a number of human diseases, including cancer. Currently, IFNs have been shown to be efficacious for the treatment of only a select number of cancers. The reason for this is unclear. Recent evidence has demonstrated that some cancer cell types seem to be defective in their ability to respond to IFN. It has been suggested that defects in IFN signaling is one mechanism by which cancer cells escape responsiveness to Type I IFNs and growth control in general. We report that transfection and enhanced expression of the Type I IFN receptor chain (IFNAR2c) in 3 different human cancer cell lines markedly increases the sensitivity of these cells to the antiproliferative effects of IFNs. In cancer cells transfected with IFNAR2c, dose response curves demonstrate a significant decrease in the concentrations of IFN required to achieve maximum cell death. Furthermore, in these transfected cells, we observe a significant increase in the number of cells undergoing apoptosis, as measured by DNA fragmentation and Caspase 3 activation. In addition, using an in vivo xenograft tumor model we show an increase in the effectiveness of systemically delivered Betaseron in decreasing tumor burden in animals in which solid tumors were generated from IFNAR2c transfected cells. These data show that specific regulation of IFN receptor expression can play a major role in determining the clinical outcome of IFN-based cancer therapeutics by regulating the relative sensitivity of cancer cells to IFN-dependent growth control.
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Affiliation(s)
- T Charis Wagner
- Department of Immunology, Berlex Bioscience Inc., Richmond, CA 94804, USA
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20
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Abstract
More than a half a century ago, interferons (IFN) were identified as antiviral cytokines. Since that discovery, IFN have been in the forefront of basic and clinical cytokine research. The pleiotropic nature of these cytokines continues to engage a large number of investigators to define their actions further. IFN paved the way for discovery of Janus tyrosine kinase (JAK)-signal transducing activators of transcription (STAT) pathways. A number of important tumor suppressive pathways are controlled by IFN. Several infectious pathogens counteract IFN-induced signaling pathways. Recent studies indicate that IFN activate several new protein kinases, including the MAP kinase family, and downstream transcription factors. This review not only details the established IFN signaling paradigms but also provides insights into emerging alternate signaling pathways and mechanisms of pathogen-induced signaling interference.
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Affiliation(s)
- Dhananjaya V Kalvakolanu
- Molecular and Cellular Biology Graduate Program, Greenebaum Cancer Center, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Hu J, Meng Q, Roy SK, Raha A, Hu J, Zhang J, Hashimoto K, Kalvakolanu DV. A novel transactivating factor that regulates interferon-gamma-dependent gene expression. J Biol Chem 2002; 277:30253-63. [PMID: 12050152 DOI: 10.1074/jbc.m202679200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have previously identified a novel interferon (IFN)-stimulated cis-acting enhancer element, gamma-IFN-activated transcriptional element (GATE). GATE differs from the known IFN-stimulated elements in its primary sequence. Preliminary analysis has indicated that the GATE-dependent transcriptional response requires the binding of novel transacting factors. A cDNA expression library derived from an IFN-gamma-stimulated murine macrophage cell line was screened with a (32)P-labeled GATE probe to identify the potential GATE-binding factors. A cDNA coding for a novel transcription-activating factor was identified. Based on its discovery, we named it as GATE-binding factor-1 (GBF-1). GBF-1 homologs are present in mouse, human, monkey, and Drosophila. It activates transcription from reporter genes carrying GATE. It possesses a strong transactivating activity but has a weak DNA binding property. GBF-1 is expressed in most tissues with relatively higher steady-state levels in heart, liver, kidney, and brain. Its expression is induced by IFN-gamma treatment. GBF-1 is present in both cytosolic and nuclear compartments. These studies thus identify a novel transactivating factor in IFN signaling pathways.
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Affiliation(s)
- Junbo Hu
- Marlene and Stewart Greenebaum Cancer Center, Department of Microbiology and Immunology, Molecular and Cellular Biology Program, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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22
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Abstract
Links between human papillomaviruses (HPVs) and cervical cancer were first suspected almost 30 years ago. DNA of specific HPV types has since been found in almost all cervical cancer biopsies. HPV oncogenes that are expressed in these cells are involved in their transformation and immortalization, and are required for the progression towards malignancy. Epidemiological studies have underlined that HPVs are the main aetiological factor for cervical cancer. But how has this knowledge been translated into the clinic to allow the prevention, screening and treatment of cervical cancer?
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