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Salisbury NJH, Amonkar S, Landazuri Vinueza J, Carter JJ, Roman A, Galloway DA. Polyomavirus ALTOs, but not MTs, downregulate viral early gene expression by activating the NF-κB pathway. Proc Natl Acad Sci U S A 2024; 121:e2403133121. [PMID: 39141346 PMCID: PMC11348336 DOI: 10.1073/pnas.2403133121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 07/04/2024] [Indexed: 08/15/2024] Open
Abstract
Polyomaviruses are small, circular dsDNA viruses that can cause cancer. Alternative splicing of polyomavirus early transcripts generates large and small tumor antigens (LT, ST) that play essential roles in viral replication and tumorigenesis. Some polyomaviruses also express middle tumor antigens (MTs) or alternate LT open reading frames (ALTOs), which are evolutionarily related but have distinct gene structures. MTs are a splice variant of the early transcript whereas ALTOs are overprinted on the second exon of the LT transcript in an alternate reading frame and are translated via an alternative start codon. Merkel cell polyomavirus (MCPyV), the only human polyomavirus that causes cancer, encodes an ALTO but its role in the viral lifecycle and tumorigenesis has remained elusive. Here, we show MCPyV ALTO acts as a tumor suppressor and is silenced in Merkel cell carcinoma (MCC). Rescuing ALTO in MCC cells induces growth arrest and activates NF-κB signaling. ALTO activates NF-κB by binding SQSTM1 and TRAF2&3 via two N-Terminal Activating Regions (NTAR1+2), resembling Epstein-Barr virus (EBV) Latent Membrane Protein 1 (LMP1). Following activation, NF-κB dimers bind the MCPyV noncoding control region (NCCR) and downregulate early transcription. Beyond MCPyV, NTAR motifs are conserved in other polyomavirus ALTOs, which activate NF-κB signaling, but are lacking in MTs that do not. Furthermore, polyomavirus ALTOs downregulate their respective viral early transcription in an NF-κB- and NTAR-dependent manner. Our findings suggest that ALTOs evolved to suppress viral replication and promote viral latency and that MCPyV ALTO must be silenced for MCC to develop.
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Affiliation(s)
| | - Supriya Amonkar
- Human Biology Division, Fred Hutchinson Cancer Center Seattle, WA98109
| | - Joselyn Landazuri Vinueza
- Human Biology Division, Fred Hutchinson Cancer Center Seattle, WA98109
- Department of Microbiology, University of Washington, Seattle, WA98109
| | - Joseph J. Carter
- Human Biology Division, Fred Hutchinson Cancer Center Seattle, WA98109
| | - Ann Roman
- Human Biology Division, Fred Hutchinson Cancer Center Seattle, WA98109
- Department of Microbiology, University of Washington, Seattle, WA98109
| | - Denise A. Galloway
- Human Biology Division, Fred Hutchinson Cancer Center Seattle, WA98109
- Department of Microbiology, University of Washington, Seattle, WA98109
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2
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Salisbury NJH, Amonkar S, Vinueza JL, Carter JJ, Roman A, Galloway DA. Polyomavirus ALTOs, but not MTs, downregulate viral early gene expression by activating the NF-κB pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.24.595774. [PMID: 38826197 PMCID: PMC11142227 DOI: 10.1101/2024.05.24.595774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Polyomaviruses are small, circular dsDNA viruses that can cause cancer. Alternative splicing of polyomavirus early transcripts generates large and small tumor antigens (LT, ST) that play essential roles in viral replication and tumorigenesis. Some polyomaviruses also express middle tumor antigens (MTs) or Alternate LT ORFs (ALTOs), which are evolutionarily related but have distinct gene structures. MTs are a splice variant of the early transcript whereas ALTOs are overprinted on the second exon of the LT transcript in an alternate reading frame and are translated via an alternative start codon. Merkel cell polyomavirus (MCPyV), the only human polyomavirus that causes cancer, encodes an ALTO but its role in the viral lifecycle and tumorigenesis has remained elusive. Here, we show MCPyV ALTO acts as a tumor suppressor and is silenced in Merkel cell carcinoma (MCC). Rescuing ALTO in MCC cells induces growth arrest and activates NF-κB signaling. ALTO activates NF-κB by binding SQSTM1 and TRAF2&3 via two N-Terminal Activating Regions (NTAR1+2), resembling Epstein-Barr virus (EBV) Latent Membrane Protein 1 (LMP1).. Following activation, NF-κB dimers bind the MCPyV non-coding control region (NCCR) and downregulate early transcription. Beyond MCPyV, NTAR motifs are conserved in other polyomavirus ALTOs, which activate NF-κB signaling, but are lacking in MTs that do not. Furthermore, polyomavirus ALTOs downregulate their respective viral early transcription in an NF-κB and NTAR dependent manner. Our findings suggest that ALTOs evolved to suppress viral replication and promote viral latency and that MCPyV ALTO must be silenced for MCC to develop.
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Affiliation(s)
- Nicholas J. H. Salisbury
- Fred Hutchinson Cancer Center, Pathogen-Associated Malignancies Integrated Research Center, Seattle, WA, 98109 USA
| | - Supriya Amonkar
- Fred Hutchinson Cancer Center, Pathogen-Associated Malignancies Integrated Research Center, Seattle, WA, 98109 USA
| | - Joselyn Landazuri Vinueza
- Fred Hutchinson Cancer Center, Pathogen-Associated Malignancies Integrated Research Center, Seattle, WA, 98109 USA
- University of Washington, Department of Microbiology, Seattle, WA, 98109, USA
| | - Joseph J. Carter
- Fred Hutchinson Cancer Center, Pathogen-Associated Malignancies Integrated Research Center, Seattle, WA, 98109 USA
| | - Ann Roman
- Fred Hutchinson Cancer Center, Pathogen-Associated Malignancies Integrated Research Center, Seattle, WA, 98109 USA
- University of Washington, Department of Microbiology, Seattle, WA, 98109, USA
| | - Denise A. Galloway
- Fred Hutchinson Cancer Center, Pathogen-Associated Malignancies Integrated Research Center, Seattle, WA, 98109 USA
- University of Washington, Department of Microbiology, Seattle, WA, 98109, USA
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Zebardast A, Latifi T, shirzad M, Goodarzi G, Ebrahimi Fana S, Samavarchi Tehrani S, Yahyapour Y. Critical involvement of circular RNAs in virus-associated cancers. Genes Dis 2023; 10:2296-2305. [PMID: 37554189 PMCID: PMC10404876 DOI: 10.1016/j.gendis.2022.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/25/2022] [Accepted: 04/06/2022] [Indexed: 12/09/2022] Open
Abstract
Virus-related cancer is cancer where viral infection leads to the malignant transformation of the host's infected cells. Seven viruses (e.g., human papillomavirus (HPV), Epstein-Barr virus (EBV), Kaposi's sarcoma herpesvirus (KSHV), Hepatitis B virus (HBV), Hepatitis C virus (HCV), Human T-lymphotropic virus (HTLV), and Merkel cell polyomavirus (MCV)) that infect humans have been identified as an oncogene and have been associated with several human malignancies. Recently, growing attention has been attracted to exploring the pathogenesis of virus-related cancers. One of the most mysterious molecules involved in carcinogenesis and progression of virus-related cancers is circular RNAs (circRNA). These emerging non-coding RNAs (ncRNAs), due to the absence of 5' and 3' ends, have high stability than linear RNAs and are found in some species across the eukaryotic organisms. Compelling evidence has revealed that viruses also encode a repertoire of circRNAs, as well as dysregulation of these viral circRNAs play a critical role in the pathogenesis and progression of different types of virus-related cancers. Therefore, understanding the exact role and function of the virally encoded circRNAs with virus-associated cancers will open a new road for increasing our knowledge about the RNA world. Hence, in this review, we will focus on emerging roles of virus-encoded circRNAs in multiple cancers, including cervical cancer, gastric cancer, Merkel cell carcinoma, nasopharyngeal carcinoma, Kaposi cancer, and liver cancer.
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Affiliation(s)
- Arghavan Zebardast
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 1417613151, Iran
| | - Tayebeh Latifi
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 1417613151, Iran
| | - Moein shirzad
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol 47176, Iran
| | - Golnaz Goodarzi
- Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran 1417613151, Iran
- Student Scientific Research Center, Tehran University of Medical Sciences, Tehran 1417613151, Iran
| | - Saeed Ebrahimi Fana
- Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran 1417613151, Iran
- Student Scientific Research Center, Tehran University of Medical Sciences, Tehran 1417613151, Iran
| | - Sadra Samavarchi Tehrani
- Department of Clinical Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran 1417613151, Iran
- Student Scientific Research Center, Tehran University of Medical Sciences, Tehran 1417613151, Iran
| | - Yousef Yahyapour
- Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol 47176, Iran
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Nomburg J, Zou W, Frost TC, Datta C, Vasudevan S, Starrett GJ, Imperiale MJ, Meyerson M, DeCaprio JA. Long-read sequencing reveals complex patterns of wraparound transcription in polyomaviruses. PLoS Pathog 2022; 18:e1010401. [PMID: 35363834 PMCID: PMC9007360 DOI: 10.1371/journal.ppat.1010401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 04/13/2022] [Accepted: 02/27/2022] [Indexed: 12/22/2022] Open
Abstract
Polyomaviruses (PyV) are ubiquitous pathogens that can cause devastating human diseases. Due to the small size of their genomes, PyV utilize complex patterns of RNA splicing to maximize their coding capacity. Despite the importance of PyV to human disease, their transcriptome architecture is poorly characterized. Here, we compare short- and long-read RNA sequencing data from eight human and non-human PyV. We provide a detailed transcriptome atlas for BK polyomavirus (BKPyV), an important human pathogen, and the prototype PyV, simian virus 40 (SV40). We identify pervasive wraparound transcription in PyV, wherein transcription runs through the polyA site and circles the genome multiple times. Comparative analyses identify novel, conserved transcripts that increase PyV coding capacity. One of these conserved transcripts encodes superT, a T antigen containing two RB-binding LxCxE motifs. We find that superT-encoding transcripts are abundant in PyV-associated human cancers. Together, we show that comparative transcriptomic approaches can greatly expand known transcript and coding capacity in one of the simplest and most well-studied viral families.
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Affiliation(s)
- Jason Nomburg
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Harvard Program in Virology, Harvard University Graduate School of Arts and Sciences, Boston, Massachusetts, United States of America
| | - Wei Zou
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Thomas C. Frost
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Harvard Program in Virology, Harvard University Graduate School of Arts and Sciences, Boston, Massachusetts, United States of America
| | - Chandreyee Datta
- Massachusetts General Hospital Cancer Center, Harvard Medical School, 185 Cambridge St, CPZN4202, Boston, Massachusetts, United States of America
- Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- Center for Regenerative Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Harvard Stem Cell Institute, Harvard University, Cambridge, Massachusetts, United States of America
| | - Shobha Vasudevan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, 185 Cambridge St, CPZN4202, Boston, Massachusetts, United States of America
- Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- Center for Regenerative Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Harvard Stem Cell Institute, Harvard University, Cambridge, Massachusetts, United States of America
| | - Gabriel J. Starrett
- Laboratory of Cellular Oncology, CCR, NCI, NIH, Bethesda, Maryland, United States of America
| | - Michael J. Imperiale
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, United States of America
- Rogel Cancer Center, Ann Arbor, Michigan, United States of America
| | - Matthew Meyerson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - James A. DeCaprio
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Harvard Program in Virology, Harvard University Graduate School of Arts and Sciences, Boston, Massachusetts, United States of America
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
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5
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Yang R, Lee EE, Kim J, Choi JH, Kolitz E, Chen Y, Crewe C, Salisbury NJH, Scherer PE, Cockerell C, Smith TR, Rosen L, Verlinden L, Galloway DA, Buck CB, Feltkamp MC, Sullivan CS, Wang RC. Characterization of ALTO-encoding circular RNAs expressed by Merkel cell polyomavirus and trichodysplasia spinulosa polyomavirus. PLoS Pathog 2021; 17:e1009582. [PMID: 33999949 PMCID: PMC8158866 DOI: 10.1371/journal.ppat.1009582] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 05/27/2021] [Accepted: 04/24/2021] [Indexed: 12/14/2022] Open
Abstract
Circular RNAs (circRNAs) are a conserved class of RNAs with diverse functions, including serving as messenger RNAs that are translated into peptides. Here we describe circular RNAs generated by human polyomaviruses (HPyVs), some of which encode variants of the previously described alternative large T antigen open reading frame (ALTO) protein. Circular ALTO RNAs (circALTOs) can be detected in virus positive Merkel cell carcinoma (VP-MCC) cell lines and tumor samples. CircALTOs are stable, predominantly located in the cytoplasm, and N6-methyladenosine (m6A) modified. The translation of MCPyV circALTOs into ALTO protein is negatively regulated by MCPyV-generated miRNAs in cultured cells. MCPyV ALTO expression increases transcription from some recombinant promoters in vitro and upregulates the expression of multiple genes previously implicated in MCPyV pathogenesis. MCPyV circALTOs are enriched in exosomes derived from VP-MCC lines and circALTO-transfected 293T cells, and purified exosomes can mediate ALTO expression and transcriptional activation in MCPyV-negative cells. The related trichodysplasia spinulosa polyomavirus (TSPyV) also expresses a circALTO that can be detected in infected tissues and produces ALTO protein in cultured cells. Thus, human polyomavirus circRNAs are expressed in human tumors and infected tissues and express proteins that have the potential to modulate the infectious and tumorigenic properties of these viruses.
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Affiliation(s)
- Rong Yang
- Department of Dermatology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Eunice E. Lee
- Department of Dermatology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Jiwoong Kim
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Joon H. Choi
- Department of Molecular Biosciences, University of Texas, Austin, Texas, United States of America
| | - Elysha Kolitz
- Department of Dermatology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Yating Chen
- Department of Molecular Biosciences, University of Texas, Austin, Texas, United States of America
| | - Clair Crewe
- Touchstone Diabetes Center, Department of Internal Medicine, the UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Nicholas J. H. Salisbury
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Philipp E. Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, the UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Clay Cockerell
- Department of Dermatology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Taylor R. Smith
- Department of Dermatology, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Leslie Rosen
- Department of Dermatology, Louisiana State University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Louisa Verlinden
- Department of Dermatology, Ghent University Hospital, Ghent, Belgium
| | - Denise A. Galloway
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Christopher B. Buck
- Lab of Cellular Oncology, NCI, NIH, Bethesda, Maryland, United States of America
| | - Mariet C. Feltkamp
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - Christopher S. Sullivan
- Department of Molecular Biosciences, University of Texas, Austin, Texas, United States of America
| | - Richard C. Wang
- Department of Dermatology, UT Southwestern Medical Center, Dallas, Texas, United States of America
- Harold C. Simmons Cancer Center, UT Southwestern Medical Center, Dallas, Texas, United States of America
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6
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Janovec V, Ryabchenko B, Škarková A, Pokorná K, Rösel D, Brábek J, Weber J, Forstová J, Hirsch I, Huérfano S. TLR4-Mediated Recognition of Mouse Polyomavirus Promotes Cancer-Associated Fibroblast-Like Phenotype and Cell Invasiveness. Cancers (Basel) 2021; 13:cancers13092076. [PMID: 33923020 PMCID: PMC8123340 DOI: 10.3390/cancers13092076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/15/2021] [Accepted: 04/21/2021] [Indexed: 11/16/2022] Open
Abstract
The tumorigenic potential of mouse polyomavirus (MPyV) has been studied for decades in cell culture models and has been mainly attributed to nonstructural middle T antigen (MT), which acts as a scaffold signal adaptor, activates Src tyrosine kinases, and possesses transforming ability. We hypothesized that MPyV could also transform mouse cells independent of MT via a Toll-like receptor 4 (TLR4)-mediated inflammatory mechanism. To this end, we investigated the interaction of MPyV with TLR4 in mouse embryonic fibroblasts (MEFs) and 3T6 cells, resulting in secretion of interleukin 6 (IL-6), independent of active viral replication. TLR4 colocalized with MPyV capsid protein VP1 in MEFs. Neither TLR4 activation nor recombinant IL-6 inhibited MPyV replication in MEFs and 3T6 cells. MPyV induced STAT3 phosphorylation through both direct and MT-dependent and indirect and TLR4/IL-6-dependent mechanisms. We demonstrate that uninfected mouse fibroblasts exposed to the cytokine environment from MPyV-infected fibroblasts upregulated the expressions of MCP-1, CCL-5, and α-SMA. Moreover, the cytokine microenvironment increased the invasiveness of MEFs and CT26 carcinoma cells. Collectively, TLR4 recognition of MPyV induces a cytokine environment that promotes the cancer-associated fibroblast (CAF)-like phenotype in noninfected fibroblasts and increases cell invasiveness.
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Affiliation(s)
- Vaclav Janovec
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (V.J.); (B.R.); (J.F.); (S.H.)
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 16000 Prague, Czech Republic; (K.P.); (J.W.)
| | - Boris Ryabchenko
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (V.J.); (B.R.); (J.F.); (S.H.)
| | - Aneta Škarková
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (A.Š.); (D.R.); (J.B.)
| | - Karolína Pokorná
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 16000 Prague, Czech Republic; (K.P.); (J.W.)
| | - Daniel Rösel
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (A.Š.); (D.R.); (J.B.)
| | - Jan Brábek
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (A.Š.); (D.R.); (J.B.)
| | - Jan Weber
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 16000 Prague, Czech Republic; (K.P.); (J.W.)
| | - Jitka Forstová
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (V.J.); (B.R.); (J.F.); (S.H.)
| | - Ivan Hirsch
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (V.J.); (B.R.); (J.F.); (S.H.)
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 16000 Prague, Czech Republic; (K.P.); (J.W.)
- Institute of Molecular Genetics of the Czech Academy of Sciences, 14220 Prague, Czech Republic
- Correspondence: ; Tel.: +420-221-951-723
| | - Sandra Huérfano
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150 Vestec, Czech Republic; (V.J.); (B.R.); (J.F.); (S.H.)
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7
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Achyut BR, Zhang H, Angara K, Mivechi NF, Arbab AS, Ko L. Oncoprotein GT198 vaccination delays tumor growth in MMTV-PyMT mice. Cancer Lett 2020; 476:57-66. [PMID: 32061755 PMCID: PMC7067666 DOI: 10.1016/j.canlet.2020.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/29/2019] [Accepted: 02/07/2020] [Indexed: 02/05/2023]
Abstract
Targeting early lesion in breast cancer is more therapeutically effective. We have previously identified an oncoprotein GT198 (PSMC3IP) in human breast cancer. Here we investigated GT198 in MMTV-PyMT mouse mammary gland tumors and found that GT198 is a shared early lesion in both species. Similar to human breast cancer even before a tumor appears, cytoplasmic GT198 is overexpressed in mouse tumor stroma including pericyte stem cells, descendent adipocytes, fibroblasts, and myoepithelial cells. Using recombinant GT198 protein as an antigen, we vaccinated MMTV-PyMT mice and found that the GT198 vaccine delayed mouse tumor growth and reduced lung metastasis. The antitumor effects were linearly correlated with vaccinated mouse serum titers of GT198 antibody, which recognized cell surface GT198 protein on viable tumor cells confirmed by FACS. Furthermore, GT198+ tumor cells isolated from MMTV-PyMT tumor induced faster tumor growths than GT198- cells when re-implanted into normal FVB/N mice. Together, this first study of GT198 vaccine in mouse showed its effectiveness in antitumor and anti-metastasis. The finding supports GT198 as a potential target in human immunotherapy since GT198 defect is shared in both human and mouse.
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Affiliation(s)
- Bhagelu R Achyut
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, USA; Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Hao Zhang
- Department of General Surgery, The First of Affiliated Hospital of Jinan University, And Institute of Precision Cancer Medicine and Pathology, Jinan University Medical College, Guangzhou, Guangdong, China; Research Center of Translational Medicine, The Second Affiliated Hospital of Shantou University Medical College, Shantou, China.
| | - Kartik Angara
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, USA; Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Nahid F Mivechi
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, USA; Department of Radiation Oncology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Ali S Arbab
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, USA; Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Lan Ko
- Georgia Cancer Center, Medical College of Georgia, Augusta University, Augusta, GA, USA; Department of Pathology, Medical College of Georgia, Augusta University, Augusta, GA, USA.
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8
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Bueno MJ, Jimenez-Renard V, Samino S, Capellades J, Junza A, López-Rodríguez ML, Garcia-Carceles J, Lopez-Fabuel I, Bolaños JP, Chandel NS, Yanes O, Colomer R, Quintela-Fandino M. Essentiality of fatty acid synthase in the 2D to anchorage-independent growth transition in transforming cells. Nat Commun 2019; 10:5011. [PMID: 31676791 PMCID: PMC6825217 DOI: 10.1038/s41467-019-13028-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 10/14/2019] [Indexed: 12/28/2022] Open
Abstract
Upregulation of fatty acid synthase (FASN) is a common event in cancer, although its mechanistic and potential therapeutic roles are not completely understood. In this study, we establish a key role of FASN during transformation. FASN is required for eliciting the anaplerotic shift of the Krebs cycle observed in cancer cells. However, its main role is to consume acetyl-CoA, which unlocks isocitrate dehydrogenase (IDH)-dependent reductive carboxylation, producing the reductive power necessary to quench reactive oxygen species (ROS) originated during the switch from two-dimensional (2D) to three-dimensional (3D) growth (a necessary hallmark of cancer). Upregulation of FASN elicits the 2D-to-3D switch; however, FASN's synthetic product palmitate is dispensable for this process since cells satisfy their fatty acid requirements from the media. In vivo, genetic deletion or pharmacologic inhibition of FASN before oncogenic activation prevents tumor development and invasive growth. These results render FASN as a potential target for cancer prevention studies.
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Affiliation(s)
- Maria J Bueno
- Breast Cancer Clinical Research Unit, CNIO - Spanish National Cancer Research Center, Madrid, Spain
| | - Veronica Jimenez-Renard
- Breast Cancer Clinical Research Unit, CNIO - Spanish National Cancer Research Center, Madrid, Spain
| | - Sara Samino
- Metabolomics Platform, Department of Electronic Engineering, Universitat Rovira i Virgili, Tarragona, Spain
- Biomedical Research Center in Diabetes and Associated Metabolic Disorders, CIBERDEM, Madrid, Spain
| | - Jordi Capellades
- Metabolomics Platform, Department of Electronic Engineering, Universitat Rovira i Virgili, Tarragona, Spain
- Biomedical Research Center in Diabetes and Associated Metabolic Disorders, CIBERDEM, Madrid, Spain
| | - Alejandra Junza
- Metabolomics Platform, Department of Electronic Engineering, Universitat Rovira i Virgili, Tarragona, Spain
- Biomedical Research Center in Diabetes and Associated Metabolic Disorders, CIBERDEM, Madrid, Spain
| | | | | | - Irene Lopez-Fabuel
- Institute of Functional Biology and Genomics (IBFG), Universidad de Salamanca, CSIC, Salamanca, Spain
- Centro de Investigación Biomédica en Red sobre Fragilidad y Envejecimiento Saludable (CIBERFES), Institute of Biomedical Research of Salamanca, 37007, Salamanca, Spain
| | - Juan P Bolaños
- Institute of Functional Biology and Genomics (IBFG), Universidad de Salamanca, CSIC, Salamanca, Spain
- Centro de Investigación Biomédica en Red sobre Fragilidad y Envejecimiento Saludable (CIBERFES), Institute of Biomedical Research of Salamanca, 37007, Salamanca, Spain
| | - Navdeep S Chandel
- Department of Medicine, Northwestern University Feinberg School of Medicine Chicago, Chicago, IL, USA
| | - Oscar Yanes
- Metabolomics Platform, Department of Electronic Engineering, Universitat Rovira i Virgili, Tarragona, Spain
- Biomedical Research Center in Diabetes and Associated Metabolic Disorders, CIBERDEM, Madrid, Spain
| | - Ramon Colomer
- Medical Oncology Hospital, Universitario La Princesa, Madrid, Spain
| | - Miguel Quintela-Fandino
- Breast Cancer Clinical Research Unit, CNIO - Spanish National Cancer Research Center, Madrid, Spain.
- Medical Oncology Hospital, Universitario Quiron, Pozuelo de Alarcon - Madrid, Spain.
- Medical Oncology, Hospital Universitario de Fuenlabrada, Fuenlabrada - Madrid, Spain.
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9
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Novel Polyomaviruses in Mammals from Multiple Orders and Reassessment of Polyomavirus Evolution and Taxonomy. Viruses 2019; 11:v11100930. [PMID: 31658738 PMCID: PMC6833039 DOI: 10.3390/v11100930] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/04/2019] [Accepted: 10/07/2019] [Indexed: 12/14/2022] Open
Abstract
As the phylogenetic organization of mammalian polyomaviruses is complex and currently incompletely resolved, we aimed at a deeper insight into their evolution by identifying polyomaviruses in host orders and families that have either rarely or not been studied. Sixteen unknown and two known polyomaviruses were identified in animals that belong to 5 orders, 16 genera, and 16 species. From 11 novel polyomaviruses, full genomes could be determined. Splice sites were predicted for large and small T antigen (LTAg, STAg) coding sequences (CDS) and examined experimentally in transfected cell culture. In addition, splice sites of seven published polyomaviruses were analyzed. Based on these data, LTAg and STAg annotations were corrected for 10/86 and 74/86 published polyomaviruses, respectively. For 25 polyomaviruses, a spliced middle T CDS was observed or predicted. Splice sites that likely indicate expression of additional, alternative T antigens, were experimentally detected for six polyomaviruses. In contrast to all other mammalian polyomaviruses, three closely related cetartiodactyl polyomaviruses display two introns within their LTAg CDS. In addition, the VP2 of Glis glis (edible dormouse) polyomavirus 1 was observed to be encoded by a spliced transcript, a unique experimental finding within the Polyomaviridae family. Co-phylogenetic analyses based on LTAg CDS revealed a measurable signal of codivergence when considering all mammalian polyomaviruses, most likely driven by relatively recent codivergence events. Lineage duplication was the only other process whose influence on polyomavirus evolution was unambiguous. Finally, our analyses suggest that an update of the taxonomy of the family is required, including the creation of novel genera of mammalian and non-mammalian polyomaviruses.
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10
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Buicko JL, Finnerty BM, Zhang T, Kim BJ, Fahey TJ, Nancy Du YC. Insights into the biology and treatment strategies of pancreatic neuroendocrine tumors. ACTA ACUST UNITED AC 2019; 2. [PMID: 31535089 DOI: 10.21037/apc.2019.06.02] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pancreatic neuroendocrine tumors (PNETs) are the second most common primary pancreatic neoplasms after pancreatic ductal adenocarcinoma. PNETs present with widely various clinical manifestation and unfavorable survival rate. The recent advances in next generation sequencing have significantly increased our understanding of the molecular landscape of PNETs and help guide the development of targeted therapies. This review intends to outline a holistic picture of the tumors by discussing current understanding of clinical presentations, up-to-date treatment strategies, novel mouse models, and molecular biology of PNETs. Furthermore, we will provide insight into the future development of more effective targeted therapies that are necessary to manage PNETs.
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Affiliation(s)
- Jessica L Buicko
- Department of Surgery, Weill Cornell Medicine, New York, NY 10065, USA
| | | | - Tiantian Zhang
- Department of Pathology & Laboratory Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Bu Jung Kim
- Department of Pathology & Laboratory Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Thomas J Fahey
- Department of Surgery, Weill Cornell Medicine, New York, NY 10065, USA
| | - Yi-Chieh Nancy Du
- Department of Pathology & Laboratory Medicine, Weill Cornell Medicine, New York, NY 10065, USA
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11
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Gedvilaite A, Tryland M, Ulrich RG, Schneider J, Kurmauskaite V, Moens U, Preugschas H, Calvignac-Spencer S, Ehlers B. Novel polyomaviruses in shrews ( Soricidae) with close similarity to human polyomavirus 12. J Gen Virol 2017; 98:3060-3067. [PMID: 29095685 DOI: 10.1099/jgv.0.000948] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Shrews (family Soricidae) have already been reported to host microorganisms pathogenic for humans. In an effort to search for additional infectious agents with zoonotic potential, we detected polyomaviruses (PyVs) in common shrew, crowned shrew, and pygmy shrew (Sorex araneus, S. coronatus and S. minutus). From these, 11 full circular genomes were determined. Phylogenetic analysis based on large T protein sequences showed that these novel PyVs form a separate clade within the genus Alphapolyomavirus. Within this clade, the phylogenetic relationships suggest host-virus co-divergence. Surprisingly, one PyV from common shrew showed a genomic sequence nearly identical to that of the human polyomavirus 12 (HPyV12). This indicated that HPyV12 is a variant of a non-human PyV that naturally infects shrews. Whether HPyV12 is a bona fide human-tropic polyomavirus arising from a recent shrew-to-human transmission event or instead reflects a technical artefact, such as consumable contamination with shrew material, needs further investigation.
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Affiliation(s)
- Alma Gedvilaite
- Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | - Morten Tryland
- Department of Arctic and Marine Biology, Arctic Infection Biology, UIT-The Arctic University of Norway, Tromsø, Norway
| | - Rainer G Ulrich
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - Julia Schneider
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany.,Present address: NMI TT Pharmaservices, c/o CoLaborator, Berlin, Germany
| | | | - Ugo Moens
- Department of Medical Biology, University of Tromsø, Tromsø, Norway
| | | | | | - Bernhard Ehlers
- Division 12 'Measles, Mumps, Rubella and Viruses Affecting Immunocompromised Patients', Robert Koch Institute, Berlin, Germany
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12
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Pesavento PA, Brostoff T, Church ME, Dela Cruz FN, Woolard KD. Polyomavirus and Naturally Occuring Neuroglial Tumors in Raccoons (Procyon Lotor). ILAR J 2016; 56:297-305. [PMID: 26912716 DOI: 10.1093/ilar/ilv036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Polyomavirus (PyV) infections are widespread in human populations and, although generally associated with silent persistence, rarely cause severe disease. Among diseases convincingly associated with natural PyV infections of humans, there are remarkably different tissue tropisms and outcomes, including progressive multifocal leukoencephalopathy, transient or progressive nephropathy, and cancer. The variable character and unpredictable outcomes of infection attest to large gaps in our basic understanding of PyV biology. In particular, the rich history of research demonstrating the oncogenic potential of PyVs in laboratory animals begs the question of why cancer is not more often associated with infection. Raccoon polyomavirus (RacPyV), discovered in 2010, is consistently identified in neuroglial tumors in free-ranging raccoons in the western United States. Exposure to RacPyV is widespread, and RacPyV is detected in tissues of raccoons without tumors. Studying the relationship of RacPyV with its natural host is a unique opportunity to uncover cogent cellular targets and protein interactions between the virus and its host. Our hypothesis is that RacPyV, as an intact episome, alters cellular pathways within neural progenitor cells and drives oncogenesis.
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Affiliation(s)
- Patricia A Pesavento
- Patricia A. Pesavento, DVM, PhD, is a professor, Terza Brostoff, is a graduate and veterinary student, Molly E. Church, MS, VMD, is a graduate student, Florante N. Dela Cruz Jr., BS, is a staff research associate, and Kevin D. Woolard, DVM, PhD, is an assistant professor in the Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine at the University of California, Davis
| | - Terza Brostoff
- Patricia A. Pesavento, DVM, PhD, is a professor, Terza Brostoff, is a graduate and veterinary student, Molly E. Church, MS, VMD, is a graduate student, Florante N. Dela Cruz Jr., BS, is a staff research associate, and Kevin D. Woolard, DVM, PhD, is an assistant professor in the Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine at the University of California, Davis
| | - Molly E Church
- Patricia A. Pesavento, DVM, PhD, is a professor, Terza Brostoff, is a graduate and veterinary student, Molly E. Church, MS, VMD, is a graduate student, Florante N. Dela Cruz Jr., BS, is a staff research associate, and Kevin D. Woolard, DVM, PhD, is an assistant professor in the Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine at the University of California, Davis
| | - Florante N Dela Cruz
- Patricia A. Pesavento, DVM, PhD, is a professor, Terza Brostoff, is a graduate and veterinary student, Molly E. Church, MS, VMD, is a graduate student, Florante N. Dela Cruz Jr., BS, is a staff research associate, and Kevin D. Woolard, DVM, PhD, is an assistant professor in the Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine at the University of California, Davis
| | - Kevin D Woolard
- Patricia A. Pesavento, DVM, PhD, is a professor, Terza Brostoff, is a graduate and veterinary student, Molly E. Church, MS, VMD, is a graduate student, Florante N. Dela Cruz Jr., BS, is a staff research associate, and Kevin D. Woolard, DVM, PhD, is an assistant professor in the Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine at the University of California, Davis
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13
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Le Sage V, Cinti A, Amorim R, Mouland AJ. Adapting the Stress Response: Viral Subversion of the mTOR Signaling Pathway. Viruses 2016; 8:v8060152. [PMID: 27231932 PMCID: PMC4926172 DOI: 10.3390/v8060152] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 05/16/2016] [Accepted: 05/19/2016] [Indexed: 02/06/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) is a central regulator of gene expression, translation and various metabolic processes. Multiple extracellular (growth factors) and intracellular (energy status) molecular signals as well as a variety of stressors are integrated into the mTOR pathway. Viral infection is a significant stress that can activate, reduce or even suppress the mTOR signaling pathway. Consequently, viruses have evolved a plethora of different mechanisms to attack and co-opt the mTOR pathway in order to make the host cell a hospitable environment for replication. A more comprehensive knowledge of different viral interactions may provide fruitful targets for new antiviral drugs.
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Affiliation(s)
- Valerie Le Sage
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
| | - Alessandro Cinti
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montréal, QC H3A 0G4, Canada.
| | - Raquel Amorim
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montréal, QC H3A 0G4, Canada.
| | - Andrew J Mouland
- HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montréal, QC H3A 0G4, Canada.
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14
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DeCant BT, Principe DR, Guerra C, Pasca di Magliano M, Grippo PJ. Utilizing past and present mouse systems to engineer more relevant pancreatic cancer models. Front Physiol 2014; 5:464. [PMID: 25538623 PMCID: PMC4255505 DOI: 10.3389/fphys.2014.00464] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 11/11/2014] [Indexed: 12/14/2022] Open
Abstract
The study of pancreatic cancer has prompted the development of numerous mouse models that aim to recapitulate the phenotypic and mechanistic features of this deadly malignancy. This review accomplishes two tasks. First, it provides an overview of the models that have been used as representations of both the neoplastic and carcinoma phenotypes. Second, it presents new modeling schemes that ultimately will serve to more faithfully capture the temporal and spatial progression of the human disease, providing platforms for improved understanding of the role of non-epithelial compartments in disease etiology as well as evaluating therapeutic approaches.
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Affiliation(s)
- Brian T DeCant
- Department of Medicine, University of Illinois at Chicago Chicago, IL, USA
| | - Daniel R Principe
- Department of Medicine, University of Illinois at Chicago Chicago, IL, USA
| | - Carmen Guerra
- Molecular Oncology Program, Centro Nacional de Investigaciones Oncológicas Madrid, Spain
| | | | - Paul J Grippo
- Department of Medicine, University of Illinois at Chicago Chicago, IL, USA
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15
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The polyomavirus middle T-antigen oncogene activates the Hippo pathway tumor suppressor Lats in a Src-dependent manner. Oncogene 2014; 34:4190-8. [PMID: 25362852 DOI: 10.1038/onc.2014.347] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 08/24/2014] [Accepted: 09/19/2014] [Indexed: 11/08/2022]
Abstract
The polyomavirus middle T antigen (PyMT) is an oncogene that activates the non-receptor tyrosine kinase, c-Src, and physically interacts with Taz (WWTR1). Taz is a pro-oncogenic transcription coactivator of the Tead transcription factors. The Hippo tumor suppressor pathway activates the kinase Lats, which phosphorylates Taz, leading to its nuclear exclusion and blunting Tead coactivation. We found that Taz was required for transformation by PyMT, but counter-intuitively, Taz was exclusively cytoplasmic in the presence of PyMT. We demonstrate that in the presence of PyMT, wild-type Taz was phosphorylated by Lats, in a Src-dependent manner. Consistently, a Lats refractory Taz mutant did not undergo cytoplasmic retention by PyMT. We show that Yap, the Taz paralog, and Shp2 phosphatase were nuclear excluded as well. Our findings describe a noncanonical activation of Lats, and an unprecedented Tead-independent role for Taz and Yap in viral-mediated oncogenesis.
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16
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Zhao Y, Kumbrink J, Lin BT, Bouton AH, Yang S, Toselli PA, Kirsch KH. Expression of a phosphorylated substrate domain of p130Cas promotes PyMT-induced c-Src-dependent murine breast cancer progression. Carcinogenesis 2013; 34:2880-90. [PMID: 23825155 DOI: 10.1093/carcin/bgt238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Elevated expression of p130Cas (Crk-associated substrate)/BCAR1 (breast cancer antiestrogen resistance 1) in human breast tumors is a marker of poor prognosis and poor overall survival. p130Cas is a downstream target of the tyrosine kinase c-Src. Signaling mediated by p130Cas through its phosphorylated substrate domain (SD) and interaction with effector molecules directly promotes tumor progression. We previously developed a constitutively phosphorylated p130Cas SD molecule, Src*/SD (formerly referred to as Src*/CasSD), which acts as decoy molecule and attenuates the transformed phenotype in v-crk-transformed murine fibroblasts and human breast cancer cells. To test the function of this molecule in vivo, we established mouse mammary tumor virus (MMTV)-long terminal repeat-Src*/SD transgenic mice in which mammary gland development and tumor formation were analyzed. Transgenic expression of the Src*/SD molecule under the MMTV-long terminal repeat promoter did not interfere with normal mammary gland development or induce tumors in mice observed for up to 11 months. To evaluate the effects of the Src*/SD molecule on tumor development in vivo, we utilized the MMTV-polyoma middle T-antigen (PyMT) murine breast cancer model that depends on c-Src. PyMT mice crossed with Src*/SD mice displayed accelerated tumor formation. The earlier onset of tumors can be explained by the interaction of the Src* domain with PyMT and targeting the fused phosphorylated SD to the membrane. At membrane compartments, it might integrate membrane-associated active signaling complexes leading to increased proliferation measured by phospho-Histone H3 staining. Although these results were unexpected, they emphasize the importance of preventing the membrane association of Src*/SD when employed as decoy molecule.
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Affiliation(s)
- Yingshe Zhao
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
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17
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Lim ES, Reyes A, Antonio M, Saha D, Ikumapayi UN, Adeyemi M, Stine OC, Skelton R, Brennan DC, Mkakosya RS, Manary MJ, Gordon JI, Wang D. Discovery of STL polyomavirus, a polyomavirus of ancestral recombinant origin that encodes a unique T antigen by alternative splicing. Virology 2013; 436:295-303. [PMID: 23276405 PMCID: PMC3693558 DOI: 10.1016/j.virol.2012.12.005] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 10/08/2012] [Accepted: 12/05/2012] [Indexed: 12/12/2022]
Abstract
The family Polyomaviridae is comprised of circular double-stranded DNA viruses, several of which are associated with diseases, including cancer, in immunocompromised patients. Here we describe a novel polyomavirus recovered from the fecal microbiota of a child in Malawi, provisionally named STL polyomavirus (STLPyV). We detected STLPyV in clinical stool specimens from USA and The Gambia at up to 1% frequency. Complete genome comparisons of two STLPyV strains demonstrated 5.2% nucleotide divergence. Alternative splicing of the STLPyV early region yielded a unique form of T antigen, which we named 229T, in addition to the expected large and small T antigens. STLPyV has a mosaic genome and shares an ancestral recombinant origin with MWPyV. The discovery of STLPyV highlights a novel alternative splicing strategy and advances our understanding of the complex evolutionary history of polyomaviruses.
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MESH Headings
- Adolescent
- Adult
- Alternative Splicing
- Antigens, Viral, Tumor/genetics
- Child
- Child, Preschool
- Cluster Analysis
- DNA, Viral/chemistry
- DNA, Viral/genetics
- Evolution, Molecular
- Feces/virology
- Female
- Gambia
- Gene Expression Regulation, Viral
- Genome, Viral
- Humans
- Infant
- Malawi
- Male
- Molecular Sequence Data
- Phylogeny
- Polyomavirus/classification
- Polyomavirus/genetics
- Polyomavirus/isolation & purification
- Polyomavirus Infections/epidemiology
- Polyomavirus Infections/virology
- Prevalence
- Recombination, Genetic
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- United States
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Affiliation(s)
- Efrem S. Lim
- Departments of Molecular Microbiology and Pathology & Immunology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
| | - Alejandro Reyes
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
| | - Martin Antonio
- Medical Research Council Unit, PO Box 273, Banjul, The Gambia
| | - Debasish Saha
- Medical Research Council Unit, PO Box 273, Banjul, The Gambia
| | | | | | - O. Colin Stine
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, 660 W Redwood St., Baltimore, Maryland, USA
| | - Rebecca Skelton
- Department of Internal Medicine, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
| | - Daniel C. Brennan
- Department of Internal Medicine, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
| | - Rajhab S. Mkakosya
- Department of Pathology, University of Malawi College of Medicine, Private Bag 360, Chichiri, Blantyre 3, Malawi
| | - Mark J. Manary
- Department of Pediatrics, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
- Department of Community Health, University of Malawi College of Medicine, Private Bag 360, Chichiri, Blantyre 3, Malawi
| | - Jeffrey I. Gordon
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
| | - David Wang
- Departments of Molecular Microbiology and Pathology & Immunology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, USA
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18
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Mitterhofer A, Tinti F, Pietropaolo V, Barile M, Chiarini F, Meçule A, Ferretti G, Poli L, Berloco P, Taliani G. Polyomavirus BK Replication in Adult Polycystic Kidney Disease Post–Renal Transplant Patients and Possible Role of Cellular Permissivity. Transplant Proc 2011; 43:1048-51. [DOI: 10.1016/j.transproceed.2011.02.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Transgenic expression of polyomavirus middle T antigen in the mouse prostate gives rise to carcinoma. J Virol 2011; 85:5581-92. [PMID: 21411524 DOI: 10.1128/jvi.02609-10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The middle T (MT) antigen of polyomavirus has provided fundamental insights into the regulation of mammalian cell growth in vitro and important animal models for the analysis of tumor induction. The mouse mammary tumor virus (MMTV)-MT model of breast cancer has been important for probing the cellular signaling pathways in mammary tumorigenesis. MT itself has no intrinsic enzymatic activity but, rather, transforms by binding to and activating key intracellular signaling molecules, phosphatidylinositol 3-kinase (PI3-kinase) being the best studied of these. Thus, MT mimics a constitutively activated receptor tyrosine kinase (RTK). Our recent work suggests that MT signaling, like that of RTKs, is often quite dependent on cellular context in vitro. Here, we examine contextual effects on signaling in animal models as well. In this study, we generated transgenic mice in which MT is expressed in the mouse prostate under the control of an (ARR)2-Probasin promoter. All male transgenic mice displayed mouse prostatic intraepithelial neoplasia (mPIN) in the ventral and dorsal/lateral prostate as early as 8 weeks of age. Notably, during the course of tumor development over time, invasive cancer, reactive stroma, and infiltration of inflammatory cells were seen. Transcriptional profiling analyses show regulation of multiple pathways, with marked upregulation of both the NF-κB and inflammatory pathways. Comparison of expression profiles of our MT prostate model with those from an MMTV-MT breast model (23) shows both tissue-specific and tissue-independent MT effects. The signature of genes regulated by MT in a tissue-independent manner may have prognostic value.
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20
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Abl family tyrosine kinases regulate sialylated ganglioside receptors for polyomavirus. J Virol 2010; 84:4243-51. [PMID: 20181697 DOI: 10.1128/jvi.00129-10] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Sialylated lipids serve as cellular receptors for polyomaviruses. Using pharmacological inhibitors and cell lines derived from knockout mice, we demonstrate that Abl family tyrosine kinases are required for replication of mouse polyomavirus and BK virus, a human polyomavirus associated with allograft failure following kidney transplantation. We show that decreasing Abl family kinase activity results in low levels of cell surface ganglioside receptors for mouse polyomavirus and that inhibition of sialidase activity promotes virion binding in the absence of Abl family kinase activity. These data provide evidence that Abl family kinases reduce ganglioside turnover in the plasma membrane by inhibiting host cell sialidase activity. Thus, Abl family kinases regulate the susceptibility of cells to polyomavirus infection by modulating gangliosides required for viral attachment.
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21
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Du YCN, Klimstra DS, Varmus H. Activation of PyMT in beta cells induces irreversible hyperplasia, but oncogene-dependent acinar cell carcinomas when activated in pancreatic progenitors. PLoS One 2009; 4:e6932. [PMID: 19812721 PMCID: PMC2758666 DOI: 10.1371/journal.pone.0006932] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 08/06/2009] [Indexed: 12/31/2022] Open
Abstract
It is unclear whether the cellular origin of various forms of pancreatic cancer involves transformation or transdifferentiation of different target cells or whether tumors arise from common precursors, with tumor types determined by the specific genetic alterations. Previous studies suggested that pancreatic ductal carcinomas might be induced by polyoma middle T antigen (PyMT) expressed in non-ductal cells. To ask whether PyMT transforms and transdifferentiates endocrine cells toward exocrine tumor phenotypes, we generated transgenic mice that carry tetracycline-inducible PyMT and a linked luciferase reporter. Induction of PyMT in β cells causes β-cell hyperplastic lesions that do not progress to malignant neoplasms. When PyMT is de-induced, β cell proliferation and growth cease; however, regression does not occur, suggesting that continued production of PyMT is not required to maintain the viable expanded β cell population. In contrast, induction of PyMT in early pancreatic progenitor cells under the control of Pdx1 produces acinar cell carcinomas and β-cell hyperplasia. The survival of acinar tumor cells is dependent on continued expression of PyMT. Our findings indicate that PyMT can induce exocrine tumors from pancreatic progenitor cells, but cells in the β cell lineage are not transdifferentiated toward exocrine cell types by PyMT; instead, they undergo oncogene-dependent hyperplastic growth, but do not require PyMT for survival.
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Affiliation(s)
- Yi-Chieh Nancy Du
- Program in Cancer Biology and Genetics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
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22
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Fluck MM, Schaffhausen BS. Lessons in signaling and tumorigenesis from polyomavirus middle T antigen. Microbiol Mol Biol Rev 2009; 73:542-63, Table of Contents. [PMID: 19721090 PMCID: PMC2738132 DOI: 10.1128/mmbr.00009-09] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The small DNA tumor viruses have provided a very long-lived source of insights into many aspects of the life cycle of eukaryotic cells. In recent years, the emphasis has been on cancer-related signaling. Here we review murine polyomavirus middle T antigen, its mechanisms, and its downstream pathways of transformation. We concentrate on the MMTV-PyMT transgenic mouse, one of the most studied models of breast cancer, which permits the examination of in situ tumor progression from hyperplasia to metastasis.
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Affiliation(s)
- Michele M Fluck
- Department of Microbiology and Molecular Genetics, Interdepartmental Program in Cell and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
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23
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Buchkovich NJ, Yu Y, Zampieri CA, Alwine JC. The TORrid affairs of viruses: effects of mammalian DNA viruses on the PI3K-Akt-mTOR signalling pathway. Nat Rev Microbiol 2008; 6:266-75. [PMID: 18311165 DOI: 10.1038/nrmicro1855] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The successful replication of mammalian DNA viruses requires that they gain control of key cellular signalling pathways that affect broad aspects of cellular macromolecular synthesis, metabolism, growth and survival. The phosphatidylinositol 3'-kinase-Akt-mammalian target of rapamycin (PI3K-Akt-mTOR) pathway is one such pathway. Mammalian DNA viruses have evolved various mechanisms to activate this pathway to obtain the benefits of Akt activation, including the maintenance of translation through the activation of mTOR. In addition, viruses must overcome the inhibition of this pathway that results from the activation of cellular stress responses during viral infection. This Review will discuss the range of mechanisms that mammalian DNA viruses use to activate this pathway, as well as the multiple mechanisms these viruses have evolved to circumvent inhibitory stress signalling.
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Affiliation(s)
- Nicholas J Buchkovich
- Department of Cancer Biology and Abramson Family Cancer Research Institute, University of Pennsylvania, 314 Biomedical Research Building, 421 Curie Blvd, Philadelphia, 19104-6142 Pennsylvania, USA
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24
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Abstract
In the last 30 years, the study of virus evolution has undergone a transformation. Originally concerned with disease and its emergence, virus evolution had not been well integrated into the general study of evolution. This chapter reviews the developments that have brought us to this new appreciation for the general significance of virus evolution to all life. We now know that viruses numerically dominate all habitats of life, especially the oceans. Theoretical developments in the 1970s regarding quasispecies, error rates, and error thresholds have yielded many practical insights into virus–host dynamics. The human diseases of HIV-1 and hepatitis C virus cannot be understood without this evolutionary framework. Yet recent developments with poliovirus demonstrate that viral fitness can be the result of a consortia, not one fittest type, a basic Darwinian concept in evolutionary biology. Darwinian principles do apply to viruses, such as with Fisher population genetics, but other features, such as reticulated and quasispecies-based evolution distinguish virus evolution from classical studies. The available phylogenetic tools have greatly aided our analysis of virus evolution, but these methods struggle to characterize the role of virus populations. Missing from many of these considerations has been the major role played by persisting viruses in stable virus evolution and disease emergence. In many cases, extreme stability is seen with persisting RNA viruses. Indeed, examples are known in which it is the persistently infected host that has better survival. We have also recently come to appreciate the vast diversity of phage (DNA viruses) of prokaryotes as a system that evolves by genetic exchanges across vast populations (Chapter 10). This has been proposed to be the “big bang” of biological evolution. In the large DNA viruses of aquatic microbes we see surprisingly large, complex and diverse viruses. With both prokaryotic and eukaryotic DNA viruses, recombination is the main engine of virus evolution, and virus host co-evolution is common, although not uniform. Viral emergence appears to be an unending phenomenon and we can currently witness a selective sweep by retroviruses that infect and become endogenized in koala bears.
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Rodriguez-Viciana P, Collins C, Fried M. Polyoma and SV40 proteins differentially regulate PP2A to activate distinct cellular signaling pathways involved in growth control. Proc Natl Acad Sci U S A 2006; 103:19290-5. [PMID: 17158797 PMCID: PMC1748219 DOI: 10.1073/pnas.0609343103] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Binding of Src family kinases to membrane-associated polyoma virus middle T-antigen (PyMT) can result in the phosphorylation of PyMT tyrosine 250, which serves as a docking site for the binding of Shc and subsequent activation of the Raf-MEK-ERK (MAP) kinase cascade. In a screen for PyMT variants that could not activate the ARF tumor suppressor, we isolated a cytoplasmic nontransforming mutant (MTA) that encoded a C-terminal truncated form of the PyMT protein. Surprisingly, MTA was able to strongly activate the MAP kinase pathway in the absence of Src family kinase and Shc binding. Interestingly, the polyoma small T-antigen (PyST), which shares with MTA both partial amino acid sequence homology and cellular location, also activates the MAP kinase cascade. Activation of the MAP kinase cascade by both MTA and PyST has been demonstrated to be PP2A-dependent. Neither MTA nor PyST activate the phosphorylation of AKT. The SV40 small T-antigen, which is similar to PyST in containing a J domain and in binding to the PP2A AC dimer, does not activate the MAP kinase cascade, but does stimulate phosphorylation of AKT in a PP2A-dependent manner. These findings highlight a novel role of PP2A in stimulating the MAP kinase cascade and indicate that the similar polyoma and SV40 small T-antigens influence PP2A to activate discrete cellular signaling pathways involved in growth control.
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Affiliation(s)
| | - Crista Collins
- Cancer Research Institute, University of California, San Francisco, CA 94143
| | - Mike Fried
- Cancer Research Institute, University of California, San Francisco, CA 94143
- *To whom correspondence should be addressed at:
Cancer Research Institute, University of California, 2340 Sutter Street, San Francisco, CA 94143-0128. E-mail:
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26
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Abstract
Consideration of virus evolution only from a disease perspective has provided a limited view of virus–host evolution. Such views assume all viruses fit predator/prey models for replication, but fail to explain the origin of disease or how viruses might make significant contributions to host evolution. On a long evolutionary time scale, the ability of a virus to persist in an individual host is a much more prevalent life strategy. Persistence can explain both origins of most viral disease and virus–host evolutionary stability. However, persistence (both genomic and epigenomic) is a much more complex and demanding virus–host relationship that is difficult to study. We must change our attitudes towards persistence if we are to understand how viruses shape the tree of life.
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Affiliation(s)
- Luis P Villarreal
- University of California, Center for Virus Research, 3232 McGaugh Hall, Irvine, CA 92697, USA
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27
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Chen L, Wang X, Fluck MM. Independent contributions of polyomavirus middle T and small T to the regulation of early and late gene expression and DNA replication. J Virol 2006; 80:7295-307. [PMID: 16840310 PMCID: PMC1563708 DOI: 10.1128/jvi.00679-06] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We previously showed that murine polyomavirus mutants that lack both middle T (MT) and small T (ST) functions have a severe pleiotropic defect in early and late viral gene expression as well as genome amplification. The respective contribution of MT and ST to this phenotype was unclear. This work separates the roles of MT and ST in both permissive mouse cells and nonpermissive rat cells. It demonstrates for the first time a role for both proteins. To gain insight into the signaling pathways that might be required, we focused on MT and its mutants. The results show that each of the major MT signaling connections, Shc, phosphatidylinositol 3'-kinase, and phospholipase C gamma1, could contribute in an additive way. Unexpectedly, a mutant lacking all these connections because the three major tyrosines had been converted to phenylalanine retained some activity. A mutant in which all six MT C-terminal tyrosines had been mutated was inactive. This suggests a novel signaling pathway for MT that uses the minor tyrosines. What is common to ST and the individual MT signaling pathways is the ability to signal to the polyomavirus enhancer, in particular to the crucial AP-1 and PEA3/ets binding sites. This connection explains the pleiotropy of MT and ST effects on transcription and DNA replication.
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Affiliation(s)
- Li Chen
- Department of Microbiology and Molecular Genetics, Interdepartmental Program in Cell and Molecular Biology, Michigan State University, East Lansing, MI 48824-1101, USA
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28
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Elfaitouri A, Hammarin AL, Blomberg J. Quantitative real-time PCR assay for detection of human polyomavirus infection. J Virol Methods 2006; 135:207-13. [PMID: 16677718 DOI: 10.1016/j.jviromet.2006.03.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 03/09/2006] [Accepted: 03/16/2006] [Indexed: 11/29/2022]
Abstract
The human polyomaviruses BK (BKV) and JC (JCV) affect immunosuppressed patients and are associated with urogenital tract (BKV) and CNS disorders (JCV) and in humans, the pathogenic role of the rhesus monkey virus, Simian virus 40 (SV40), is uncertain. These three viruses have somewhat overlapping tissue pathogenicity and detection of all three polyomaviruses is desirable. A broadly targeted, simple, single tube real-time degenerated quantitative PCR (QPCR) technique for detection of JCV, BKV and SV40 DNA was developed. To avoid false positive results, due to contamination with commonly used SV40 T-antigen plasmids, a conserved region of the VP2 gene was targeted. Down to 1-10 copies of target DNA per PCR reaction were detected. The QPCR was compared with a nested PCR on 41 clinical samples (urine, serum and plasma): 24 (58.5%) tested positive by nested PCR, whereas 31 (75.6%) were positive with QPCR. One CSF sample, from a patient with progressive multifocal leukoencephalopathy, was negative with the nested PCR but determined as positive by QPCR. Sera from 24 blood donors were negative with QPCR. The QPCR described had a high sensitivity. Its specificity was confirmed sequencing. The QPCR is simple to perform and is valuable for diagnosis of polyomavirus infection.
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Affiliation(s)
- Amal Elfaitouri
- Section of Virology, Department of Medical Sciences, Uppsala University Hospital, S-571-85 Uppsala, Sweden
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29
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Cecena G, Wen F, Cardiff RD, Oshima RG. Differential sensitivity of mouse epithelial tissues to the polyomavirus middle T oncogene. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:310-20. [PMID: 16400032 PMCID: PMC1592648 DOI: 10.2353/ajpath.2006.050443] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To determine how different epithelial cell types respond to the same oncogenic stimulation, we have used a modified human keratin 18 gene to conditionally express the polyomavirus middle T antigen (PyMT) oncogene in simple epithelial tissues of transgenic mice. Activation of PyMT expression by transgenic Cre recombinase in mammary epithelial cells resulted in carcinomas in all bitransgenic females. PyMT expression induced by K18-driven Cre in internal epithelial organs resulted in pancreatic acinar metaplasia and ductal dysplasia with remarkable desmoplastic stromal responses in all 25 bitransgenic mice. Hepatoma formation with altered lipid metabolism and gastric adenocarcinoma occurred in 96 and 54% of these mice, respectively. Elevated PyMT RNA expression also correlated with intraepithelial neoplasia in the prostate. Activated Erk2 was found in mammary tumors, pancreatic tissues, and affected livers. Hes1 RNA, a target of Notch signaling that has been implicated downstream of Ras pathway activation, was elevated in pancreatic and liver lesions. The variety of responses of different epithelia to PyMT demonstrates the importance of the differentiated state in interpreting oncogenic signals.
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Affiliation(s)
- Grace Cecena
- Oncodevelopmental Biology Program, Cancer Research Center, The Burnham Institute, La Jolla, CA 92037, USA
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30
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Rodriguez-Viciana P, Collins CH, Moule MG, Fried M. Chromosomal instability at a mutational hotspot in polyoma middle T-antigen affects its ability to activate the ARF-p53 tumor suppressor pathway. Oncogene 2006; 25:1454-62. [PMID: 16261156 DOI: 10.1038/sj.onc.1209197] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Revised: 09/20/2005] [Accepted: 09/22/2005] [Indexed: 11/09/2022]
Abstract
We have isolated spontaneous mutants of polyoma virus middle T-antigen (PyMT) that do not activate the ARF-p53 pathway based on their inability to block REF52 cell division. The REF52 cells containing these mutants have a flat untransformed morphological phenotype and do not express the ARF protein. The PyMT mutations in the different cell isolates so far analysed occur at a mutational hotspot in the PyMT sequence between nucleotides 1241 and 1249, which contains nine consecutive cytosines. In one set of mutants a single cytosine was deleted, while in another mutant set an additional cytosine was inserted. Both these mutations result in frameshifts, generating altered PyMT proteins containing amino-acid sequences derived from each of the two other alternative reading frames of the polyoma virus early region. Both types of mutations result in the loss of the C-terminal PyMT region containing the membrane-binding hydrophobic region and result is mislocalization of the PyMT mutant proteins. Revertant wild-type PyMT (containing nine cytosines) was easily detected in transformants generated after infection of REF52 cells expressing high amounts of dominant negative p53 with retroviruses containing either mutation. We demonstrate that wild-type PyMT revertants are derived from mutations in the hotspot sequence of the integrated mutant PyMT sequences.
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Affiliation(s)
- P Rodriguez-Viciana
- UCSF Cancer Research Institute, 2340 Sutter Street, San Francisco, California 94115, USA
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31
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The Role of Phosphoinositide 3-Kinase-Akt Signaling in Virus Infection. APOPTOSIS, CELL SIGNALING, AND HUMAN DISEASES 2006. [PMCID: PMC7120950 DOI: 10.1007/978-1-59745-199-4_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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32
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Zhang S, McNees AL, Butel JS. Quantification of vertical transmission of Murine polyoma virus by real-time quantitative PCR. J Gen Virol 2005; 86:2721-2729. [PMID: 16186225 DOI: 10.1099/vir.0.81168-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pathogenesis studies of viral infectionsin vivorequire sensitive assay methods. A sensitive and specific real-time quantitative PCR (RQ-PCR) assay was developed to detectMurine polyoma virus(MuPyV) DNA sequences. A quantitative assay to measure the single-copy murine wild-type p53 gene was developed to normalize viral gene copies to cell numbers. Both assays were sensitive over a seven-log dynamic range, with a reproducible detection limit of 10 copies per reaction. To determine viral loads and tissue distribution following vertical transmission of MuPyV, pregnant BALB/c mice were inoculated intraperitoneally with virus in late pregnancy. Progeny animals born to infected mothers were followed for 21 days. Viral loads in four tissues (salivary gland, kidney, liver and spleen) were highest at 7 days after birth and dropped to low levels by 14 and 21 days of age, with loads ranging from 5 to 2 million MuPyV copies per 103cells. Significant animal-to-animal variation occurred. Fourteen of 21 (67 %) progeny were virus-positive in one or more tissue samples. Transplacental transmission was observed in 6/7 (86 %) litters. Infected fetuses per positive litter ranged from 1/7 (14 %) to 5/6 (83 %) with viral loads ranging from 5 to 25 417 MuPyV copies per 1000 fetal cells. Maternal tissues and blood were frequently highly positive 2 days after inoculation, but viral loads were low by day 14. This study demonstrated the vertical transmission, including transplacental transmission, of MuPyV following acute infection of pregnant mice. It should be considered that there is a possibility that other polyomaviruses, including those in humans, may be vertically transmitted.
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Affiliation(s)
- Shaojie Zhang
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, MS BCM385, Houston, TX 77030, USA
| | - Adrienne L McNees
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, MS BCM385, Houston, TX 77030, USA
| | - Janet S Butel
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, MS BCM385, Houston, TX 77030, USA
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33
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Lewis BC, Klimstra DS, Socci ND, Xu S, Koutcher JA, Varmus HE. The absence of p53 promotes metastasis in a novel somatic mouse model for hepatocellular carcinoma. Mol Cell Biol 2005; 25:1228-37. [PMID: 15684377 PMCID: PMC548003 DOI: 10.1128/mcb.25.4.1228-1237.2005] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have generated a mouse model for hepatocellular carcinoma using somatic delivery of oncogene-bearing avian retroviral vectors to the liver cells of mice expressing the viral receptor TVA under the control of the albumin gene promoter (Alb-TVA mice). Viruses encoding mouse polyoma virus middle T antigen (PyMT) induced tumors, which can be visualized with magnetic resonance imaging, in 65% of TVA-positive animals. While these tumors can exceed 10 mm in diameter, they do not invade locally or metastasize to the lungs. Delivery of PyMT-expressing viruses to Alb-TVA mice lacking an intact p53 gene does not increase tumor incidence. However, the resulting tumors are poorly differentiated, invasive, and metastatic to the lungs. Gene expression microarrays identified over 100 genes that are differentially expressed between tumors found in p53 wild-type and p53 null mice. Some of these genes, such as cathepsin E and Igf2, have been previously implicated in tumor cell migration and invasion. Tumors induced in p53 null, TVA transgenic mice by PyMT mutants with changes in specific tyrosine residues fail to form metastases, indicating that metastasis is dependent on both the oncogene and the absence of p53.
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MESH Headings
- Animals
- Antigens, Viral, Tumor/metabolism
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Carcinoma, Hepatocellular/virology
- Cathepsin E/metabolism
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/physiology
- Genes, p53/physiology
- Insulin-Like Growth Factor II/metabolism
- Liver Neoplasms, Experimental/metabolism
- Liver Neoplasms, Experimental/pathology
- Liver Neoplasms, Experimental/virology
- Lung Neoplasms/metabolism
- Lung Neoplasms/pathology
- Lung Neoplasms/secondary
- Magnetic Resonance Imaging
- Mice
- Mice, Transgenic
- Mutation/genetics
- Polyomavirus/metabolism
- Retroviridae/metabolism
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Affiliation(s)
- Brian C Lewis
- University of Massachusetts Medical School, 364 Plantation St., LRB 521, Worcester, MA 01605, USA.
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34
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Rahn JJ, Gibbs PDL, Schmale MC. Patterns of transcription of a virus-like agent in tumor and non-tumor tissues in bicolor damselfish. Comp Biochem Physiol C Toxicol Pharmacol 2004; 138:401-9. [PMID: 15533798 DOI: 10.1016/j.cca.2004.06.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2004] [Revised: 06/18/2004] [Accepted: 06/20/2004] [Indexed: 11/29/2022]
Abstract
Damselfish neurofibromatosis (DNF) is a transmissible disease characterized by peripheral nerve sheath and pigment cell tumors which occurs in bicolor damselfish (Stegastes partitus) on Florida reefs. The damselfish virus-like agent (DVLA) is associated with the development of DNF and contains a 2.4-kb DNA genome which was found at high levels in tumors and tumor-derived cell lines and at lower levels in non-tumor tissues of both spontaneously diseased fish (TF) and fish with experimentally induced tumors (EF). An analysis of transcription patterns revealed up to five DVLA derived RNAs ranging in size from 300 to 1400 bp in these cell types. DNA was the most commonly distributed DVLA component in TF and EF followed by RNA. Prevalence of transcripts varied by tissue type. The smallest transcripts were the most common in all cell types and the most complete patterns, which included the larger transcripts, were observed primarily in tumors. The presence of viral RNAs in addition to DNA in non-tumor tissues suggested these tissues were infected by DVLA and indicated a wide tissue tropism for this agent. The high levels of DVLA nucleic acids found in tumors suggest that replication is occurring there. However, the potential for DVLA replication in other tissues where only a limited range of transcripts were present is not known. The mechanism of tumorigenesis by this agent is unknown. However, the association of the larger transcripts with most tumor tissues and their absence in most non-tumor tissues suggests that these RNAs may be involved in tumor formation.
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Affiliation(s)
- Jennifer J Rahn
- Division of Marine Biology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy., Miami, FL 33149, USA
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35
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Klucky B, Koch B, Radolf M, Steinlein P, Wintersberger E. Polyomavirus tumorantigens have a profound effect on gene expression in mouse fibroblasts. Oncogene 2004; 23:4707-21. [PMID: 15122341 DOI: 10.1038/sj.onc.1207640] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Polyomavirus (Py) large and small tumorantigens together are competent to induce S phase in growth-arrested mouse fibroblasts. The capacity of the large tumorantigen to bind the pocket proteins, pRB, p130 and p107, is important for the transactivation of DNA synthesis enzymes and the cyclins E and A, while the interference of small tumorantigen with protein phosphatase PP2A causes a destabilization of the cdk2 inhibitor p27, and thus leads to strong cyclin E- and cyclin A-dependent cdk2 activity. Py small tumorantigen, in addition, is able to transactivate cyclin A. Hence, this protein might have a much wider effect on gene expression in arrested mouse fibroblasts than hitherto suspected. This may have a profound part in the known capacity of Py to form tumors in mice. Therefore, it was interesting to gain an insight into the spectrum of transcriptional deregulation by Py tumorantigens. Accordingly, we performed microarray analysis of quiescent mouse fibroblasts in the absence and presence of small or large tumorantigen. We found that the viral proteins can induce or repress a great variety of genes beyond those involved in the S phase induction and DNA synthesis. The results of the microarray analysis were confirmed for selected genes by several methods, including real-time PCR. Interestingly, a mutation of the binding site for pocket proteins in case of LT and for PP2A in case of ST has a variable effect on the deregulation of genes by the viral proteins depending on the gene in question. In fact, some genes are transactivated by LT as well as ST completely independent of an interaction with their major cellular targets, pocket proteins and PP2A, respectively.
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Affiliation(s)
- Britta Klucky
- Institute of Medical Biochemistry, Division of Molecular Biology, Medical University of Vienna, Dr. Bohrgasse 9, A-1030 Vienna, Austria
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36
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Lewis BC, Klimstra DS, Varmus HE. The c-myc and PyMT oncogenes induce different tumor types in a somatic mouse model for pancreatic cancer. Genes Dev 2003; 17:3127-38. [PMID: 14681205 PMCID: PMC305263 DOI: 10.1101/gad.1140403] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We have generated a mouse model for pancreatic cancer through the somatic delivery of oncogene-bearing avian retroviruses to mice that express TVA, the receptor for avian leukosis sarcoma virus subgroup A (ALSV-A), under the control of the elastase promoter. Delivery of ALSV-A-based RCAS vectors encoding either mouse polyoma virus middle T antigen (PyMT) or c-Myc to elastase-tv-a transgenic, Ink4a/Arf null mice induced the formation of pancreatic tumors. RCAS-PyMT induced pancreatic tumors with the histologic features of acinar or ductal carcinomas. The induced pancreatic lesions express Pdx1, a marker for pancreas progenitor cells, and many tumors express markers for both exocrine and endocrine cell lineages, suggesting that the tumors may be derived from progenitor cells. In contrast, RCAS-c-myc induced endocrine tumors exclusively, as determined by histology and detection of differentiation markers. Thus, specific oncogenes can induce the formation of different pancreatic tumor types in a single transgenic line, most likely from one or more types of multipotential progenitor cells. Our model appears to be useful for elucidating the genetic alterations, target cells, and signaling pathways that are important in the genesis of different types of pancreatic cancer.
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MESH Headings
- Animals
- Antigens, Polyomavirus Transforming/physiology
- Avian Leukosis Virus/genetics
- Avian Proteins
- Biomarkers, Tumor/analysis
- Carcinoma in Situ/genetics
- Carcinoma in Situ/metabolism
- Carcinoma in Situ/pathology
- Carcinoma, Acinar Cell/genetics
- Carcinoma, Acinar Cell/metabolism
- Carcinoma, Acinar Cell/pathology
- Carcinoma, Pancreatic Ductal/genetics
- Carcinoma, Pancreatic Ductal/metabolism
- Carcinoma, Pancreatic Ductal/pathology
- Cell Transformation, Neoplastic/pathology
- Cyclin-Dependent Kinase Inhibitor p16/physiology
- Cystadenocarcinoma/genetics
- Cystadenocarcinoma/metabolism
- Cystadenocarcinoma/pathology
- DNA-Binding Proteins/metabolism
- Genetic Vectors
- Humans
- Insulinoma/pathology
- Mice
- Mice, Knockout
- Mice, Transgenic
- Paired Box Transcription Factors
- Pancreas/pathology
- Pancreatic Elastase/metabolism
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Plasmids/genetics
- Proto-Oncogene Proteins c-myc/physiology
- Receptors, Virus/genetics
- Receptors, Virus/metabolism
- Transcription Factors/metabolism
- Transfection
- Tumor Suppressor Protein p14ARF/physiology
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Affiliation(s)
- Brian C Lewis
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
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