1
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James CD, Youssef A, Prabhakar AT, Otoa R, Roe JD, Witt A, Lewis RL, Bristol ML, Wang X, Zhang K, Li R, Morgan IM. Human papillomavirus 16 replication converts SAMHD1 into a homologous recombination factor and promotes its recruitment to replicating viral DNA. J Virol 2024; 98:e0082624. [PMID: 39194246 PMCID: PMC11406955 DOI: 10.1128/jvi.00826-24] [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: 05/15/2024] [Accepted: 07/24/2024] [Indexed: 08/29/2024] Open
Abstract
We have demonstrated that SAMHD1 (sterile alpha motif and histidine-aspartic domain HD-containing protein 1) is a restriction factor for the human papillomavirus 16 (HPV16) life cycle. Here, we demonstrate that in HPV-negative cervical cancer C33a cells and human foreskin keratinocytes immortalized by HPV16 (HFK+HPV16), SAMHD1 is recruited to E1-E2 replicating DNA. Homologous recombination (HR) factors are required for HPV16 replication, and viral replication promotes phosphorylation of SAMHD1, which converts it from a dNTPase to an HR factor independent from E6/E7 expression. A SAMHD1 phospho-mimic (SAMHD1 T592D) reduces E1-E2-mediated DNA replication in C33a cells and has enhanced recruitment to the replicating DNA. In HFK+HPV16 cells, SAMHD1 T592D is recruited to the viral DNA and attenuates cellular growth, but does not attenuate growth in isogenic HFK cells immortalized by E6/E7 alone. SAMHD1 T592D also attenuates the development of viral replication foci following keratinocyte differentiation. The results indicated that enhanced SAMHD1 phosphorylation could be therapeutically beneficial in cells with HPV16 replicating genomes. Protein phosphatase 2A (PP2A) can dephosphorylate SAMHD1, and PP2A function can be inhibited by endothall. We demonstrate that endothall reduces E1-E2 replication and promotes SAMHD1 recruitment to E1-E2 replicating DNA, mimicking the SAMHD1 T592D phenotypes. Finally, we demonstrate that in head and neck cancer cell lines with HPV16 episomal genomes, endothall attenuates their growth and promotes recruitment of SAMHD1 to the viral genome. The results suggest that targeting cellular phosphatases has therapeutic potential for the treatment of HPV infections and cancers. IMPORTANCE Human papillomaviruses (HPVs) are causative agents in around 5% of all human cancers. The development of anti-viral therapeutics depends upon an increased understanding of the viral life cycle. Here, we demonstrate that HPV16 replication converts sterile alpha motif and histidine-aspartic domain HD-containing protein 1 (SAMHD1) into a homologous recombination (HR) factor via phosphorylation. This phosphorylation promotes recruitment of SAMHD1 to viral DNA to assist with replication. A SAMHD1 mutant that mimics phosphorylation is hyper-recruited to viral DNA and attenuates viral replication. Expression of this mutant in HPV16-immortalized cells attenuates the growth of these cells, but not cells immortalized by the viral oncogenes E6/E7 alone. Finally, we demonstrate that the phosphatase inhibitor endothall promotes hyper-recruitment of endogenous SAMHD1 to HPV16 replicating DNA and can attenuate the growth of both HPV16-immortalized human foreskin keratinocytes (HFKs) and HPV16-positive head and neck cancer cell lines. We propose that phosphatase inhibitors represent a novel tool for combating HPV infections and disease.
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Affiliation(s)
- Claire D James
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Aya Youssef
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Apurva T Prabhakar
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Raymonde Otoa
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Jenny D Roe
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Austin Witt
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Rachel L Lewis
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Molly L Bristol
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
- VCU Massey Cancer Center, Richmond, Virginia, USA
| | - Xu Wang
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Kun Zhang
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
| | - Renfeng Li
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Hillman Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Iain M Morgan
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, Virginia, USA
- VCU Massey Cancer Center, Richmond, Virginia, USA
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2
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Prabhakar AT, Morgan IM. A new role for human papillomavirus 16 E2: Mitotic activation of the DNA damage response to promote viral genome segregation. Tumour Virus Res 2024; 18:200291. [PMID: 39245413 PMCID: PMC11416546 DOI: 10.1016/j.tvr.2024.200291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Revised: 09/03/2024] [Accepted: 09/05/2024] [Indexed: 09/10/2024] Open
Abstract
Human papillomaviruses (HPV) are causative agents in around 5% of all human cancers. To identify and develop new targeted HPV therapeutics we must enhance our understanding of the viral life cycle and how it interacts with the host. The HPV E2 protein dimerizes and binds to 12bp target sequences in the viral genome and segregates the viral genome during mitosis. In this function, E2 binds to the viral genome and the host chromatin simultaneously, ensuring viral genomes reside in daughter nuclei following cell division. We have demonstrated that a mitotic interaction between E2 and the DNA damage response (DDR) protein TOPBP1 is required for E2 segregation function. In non-infected cells, following DNA damage, TOPBP1 is recruited to the mitotic host genome via interaction with MDC1 and this interaction protects DNA integrity during mitosis. Recently we demonstrated that the E2-TOPBP1 interaction activates the DNA damage response (DDR) during mitosis independently from external stimuli, promoting TOPBP1 interaction with mitotic chromatin and therefore segregation of the viral genome. Therefore, the virus has hijacked an existing host mechanism in order to segregate the viral genome. This intricate E2 function will be described and discussed.
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Affiliation(s)
- Apurva T Prabhakar
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, VA, 23298, USA.
| | - Iain M Morgan
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, VA, 23298, USA; VCU Massey Cancer Center, Richmond, VA, 23298, USA.
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3
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Liu Y, Niu M, Luo Y, Pan M, Hong S. DNA damage response and inflammatory response: Two traffic lights for HPVs on the road to transformation. J Med Virol 2024; 96:e29815. [PMID: 39073137 DOI: 10.1002/jmv.29815] [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: 01/05/2024] [Revised: 06/17/2024] [Accepted: 07/08/2024] [Indexed: 07/30/2024]
Abstract
Human papillomaviruses (HPVs) are non-enveloped double-stranded DNA viruses. When HPV infection persists, infected tissues can develop many HPV-related diseases such as cervical cancer and head and neck squamous cell carcinoma. To establish their persistent infection, HPVs have evolved mechanisms to manipulate the host cellular processes such as DNA damage response (DDR), which includes homologous recombination, nonhomologous end joining, and microhomology-mediated end joining. Additionally, HPVs utilize host inflammatory processes to facilitate their life cycles. Here, we bridge the concepts of DDR and inflammatory response, and discuss how HPV proteins orchestrate a sophisticated manipulation of DDR and inflammation to promote their viral replication, ultimately fostering the progression of infected cells towards oncogenic transformation to malignancy.
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Affiliation(s)
- Yanfei Liu
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Mengda Niu
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Ying Luo
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Min Pan
- Department of Otorhinolaryngology, The First Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Shiyuan Hong
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
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4
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Wendel S, Wallace NA. Interactions among human papillomavirus proteins and host DNA repair factors differ during the viral life cycle and virus-induced tumorigenesis. mSphere 2023; 8:e0042723. [PMID: 37850786 PMCID: PMC10732048 DOI: 10.1128/msphere.00427-23] [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] [Indexed: 10/19/2023] Open
Abstract
This review focuses on the impact of human papillomavirus (HPV) oncogenes on DNA repair pathways with a particular focus on how these relationships change as productive HPV infections transition to malignant lesions. We made specific efforts to incorporate advances in the understanding of HPV and DNA damage repair over the last 4 years. We apologize for any articles that we missed in compiling this report.
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Affiliation(s)
- Sebastian Wendel
- Kansas State University, Division of Biology, Manhattan, Kansas, USA
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5
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Studstill CJ, Mac M, Moody CA. Interplay between the DNA damage response and the life cycle of DNA tumor viruses. Tumour Virus Res 2023; 16:200272. [PMID: 37918513 PMCID: PMC10685005 DOI: 10.1016/j.tvr.2023.200272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/26/2023] [Accepted: 10/29/2023] [Indexed: 11/04/2023] Open
Abstract
Approximately 20 % of human cancers are associated with virus infection. DNA tumor viruses can induce tumor formation in host cells by disrupting the cell's DNA replication and repair mechanisms. Specifically, these viruses interfere with the host cell's DNA damage response (DDR), which is a complex network of signaling pathways that is essential for maintaining the integrity of the genome. DNA tumor viruses can disrupt these pathways by expressing oncoproteins that mimic or inhibit various DDR components, thereby promoting genomic instability and tumorigenesis. Recent studies have highlighted the molecular mechanisms by which DNA tumor viruses interact with DDR components, as well as the ways in which these interactions contribute to viral replication and tumorigenesis. Understanding the interplay between DNA tumor viruses and the DDR pathway is critical for developing effective strategies to prevent and treat virally associated cancers. In this review, we discuss the current state of knowledge regarding the mechanisms by which human papillomavirus (HPV), merkel cell polyomavirus (MCPyV), Kaposi's sarcoma-associated herpesvirus (KSHV), and Epstein-Barr virus (EBV) interfere with DDR pathways to facilitate their respective life cycles, and the consequences of such interference on genomic stability and cancer development.
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Affiliation(s)
- Caleb J Studstill
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States
| | - Michelle Mac
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States
| | - Cary A Moody
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, United States.
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6
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James CD, Youssef A, Prabhakar AT, Otoa R, Witt A, Lewis RL, Bristol ML, Wang X, Zhang K, Li R, Morgan IM. Human Papillomavirus 16 replication converts SAMHD1 into a homologous recombination factor and promotes its recruitment to replicating viral DNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.13.566899. [PMID: 38014153 PMCID: PMC10680734 DOI: 10.1101/2023.11.13.566899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
We have demonstrated that SAMHD1 (sterile alpha motif and histidine-aspartic domain HD-containing protein 1) is a restriction factor for the HPV16 life cycle. Here we demonstrate that in HPV negative cervical cancer C33a cells and human foreskin keratinocytes immortalized by HPV16 (HFK+HPV16), SAMHD1 is recruited to E1-E2 replicating DNA. Homologous recombination (HR) factors are required for HPV16 replication and viral replication promotes phosphorylation of SAMHD1, which converts it from a dNTPase to an HR factor independent from E6/E7 expression. A SAMHD1 phosphor-mimic (SAMHD1 T592D) reduces E1-E2 mediated DNA replication in C33a cells and has enhanced recruitment to the replicating DNA. In HFK+HPV16 cells SAMHD1 T592D is recruited to the viral DNA and attenuates cellular growth, but does not attenuate growth in isogenic HFK cells immortalized by E6/E7 alone. SAMHD1 T592D also attenuates the development of viral replication foci following keratinocyte differentiation. The results indicated that enhanced SAMHD1 phosphorylation could be therapeutically beneficial in cells with HPV16 replicating genomes. Protein phosphatase 2A (PP2A) can dephosphorylate SAMHD1 and PP2A function can be inhibited by endothall. We demonstrate that endothall reduces E1-E2 replication and promotes SAMHD1 recruitment to E1-E2 replicating DNA, mimicking the SAMHD1 T592D phenotypes. Finally, we demonstrate that in head and neck cancer cell lines with HPV16 episomal genomes endothall attenuates their growth and promotes recruitment of SAMHD1 to the viral genome. The results suggest that targeting cellular phosphatases has therapeutic potential for the treatment of HPV infections and cancers. Importance Human papillomaviruses are causative agents in around 5% of all human cancers. The development of anti-viral therapeutics depends upon an increased understanding of the viral life cycle. Here we demonstrate that HPV16 replication converts SAMHD1 into an HR factor via phosphorylation. This phosphorylation promotes recruitment of SAMHD1 to viral DNA to assist with replication. A SAMHD1 mutant that mimics phosphorylation is hyper-recruited to viral DNA and attenuates viral replication. Expression of this mutant in HPV16 immortalized cells attenuates the growth of these cells, but not cells immortalized by the viral oncogenes E6/E7 alone. Finally, we demonstrate that the phosphatase inhibitor endothall promotes hyper-recruitment of endogenous SAMHD1 to HPV16 replicating DNA and can attenuate the growth of both HPV16 immortalized human foreskin keratinocytes and HPV16 positive head and neck cancer cell lines. We propose that phosphatase inhibitors represent a novel tool for combating HPV infections and disease.
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7
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Abstract
High-risk human papillomaviruses (HPVs) are associated with several human cancers. HPVs are small, DNA viruses that rely on host cell machinery for viral replication. The HPV life cycle takes place in the stratified epithelium, which is composed of different cell states, including terminally differentiating cells that are no longer active in the cell cycle. HPVs have evolved mechanisms to persist and replicate in the stratified epithelium by hijacking and modulating cellular pathways, including the DNA damage response (DDR). HPVs activate and exploit DDR pathways to promote viral replication, which in turn increases the susceptibility of the host cell to genomic instability and carcinogenesis. Here, we review recent advances in our understanding of the regulation of the host cell DDR by high-risk HPVs during the viral life cycle and discuss the potential cellular consequences of modulating DDR pathways.
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Affiliation(s)
- Caleb J Studstill
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA;
| | - Cary A Moody
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA;
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8
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Bruyere D, Roncarati P, Lebeau A, Lerho T, Poulain F, Hendrick E, Pilard C, Reynders C, Ancion M, Luyckx M, Renard M, Jacob Y, Twizere JC, Peiffer R, Peulen O, Delvenne P, Hubert P, McBride A, Gillet N, Masson M, Herfs M. Human papillomavirus E6/E7 oncoproteins promote radiotherapy-mediated tumor suppression by globally hijacking host DNA damage repair. Theranostics 2023; 13:1130-1149. [PMID: 36793865 PMCID: PMC9925306 DOI: 10.7150/thno.78091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 01/18/2023] [Indexed: 02/04/2023] Open
Abstract
Rationale: Whatever the mucosa primary infected, HPV-positive cancers are traditionally associated with a favorable outcome, attributable to a high sensitivity to radiation therapy. However, the direct impact of viral E6/E7 oncoproteins on the intrinsic cellular radiosensitivity (and, globally, on host DNA repair) remains mostly speculative. Methods: Using several isogenic cell models expressing HPV16 E6 and/or E7, the effect of viral oncoproteins on global DNA damage response was first investigated by in vitro/in vivo approaches. The binary interactome of each individual HPV oncoprotein with factors involved in the various host DNA damage/repair mechanisms was then precisely mapped by Gaussia princeps luciferase complementation assay (and validated by co-immunoprecipitation). The stability/half-life of protein targets for HPV E6 and/or E7 as well as their subcellular localizations were determined. At last, the host genome integrity following E6/E7 expression and the synergy between radiotherapy and compounds targeting DNA repair were analyzed. Results: We first showed that the sole expression of one viral oncoprotein from HPV16 was able to significantly increase the sensitivity to irradiation of cells without affecting their basal viability parameters. In total, 10 novel targets (CHEK2, CLK2, CLK2/3, ERCC3, MNAT1, PER1, RMI1, RPA1, UVSSA and XRCC6) for E6 and 11 (ALKBH2, CHEK2, DNA2, DUT, ENDOV, ERCC3, PARP3, PMS1, PNKP, POLDIP2 and RBBP8) for E7 were identified. Importantly, not degraded following their interaction with E6 or E7, these proteins have been shown to be less linked to host DNA and to colocalize with HPV replication foci, denoting their crucial implication in viral life cycle. Finally, we found that E6/E7 oncoproteins globally jeopardize host genome integrity, increase the cellular sensitivity to DNA repair inhibitors and enhance their synergy with radiotherapy. Conclusion: Taken together, our findings provide a molecular insight into the direct hijacking of host DNA damage/repair responses by HPV oncoproteins, demonstrate the significant impact of this phenomenon on both intrinsic cellular radiosensitivity and host DNA integrity and suggest novel connected therapeutic vulnerabilities.
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Affiliation(s)
- Diane Bruyere
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Patrick Roncarati
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Alizee Lebeau
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Thomas Lerho
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Florian Poulain
- Namur Research Institute for Life Sciences (NARILIS), Integrated Veterinary Research Unit (URVI), University of Namur, Namur, Belgium
| | - Elodie Hendrick
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Charlotte Pilard
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Celia Reynders
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Marie Ancion
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Margaux Luyckx
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Michael Renard
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Yves Jacob
- Unit of Molecular Genetics of RNA Viruses, UMR 3569, CNRS, Pasteur Institute, University of Paris Diderot, 75015 Paris, France
| | - Jean-Claude Twizere
- Laboratory of Signaling and Protein Interactions, GIGA-Molecular Biology of Diseases, University of Liege, 4000 Liege, Belgium
| | - Raphael Peiffer
- Metastasis Research Laboratory, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Olivier Peulen
- Metastasis Research Laboratory, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Philippe Delvenne
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium.,Department of Pathology, University Hospital of Liege, 4000 Liege, Belgium
| | - Pascale Hubert
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
| | - Alison McBride
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Nicolas Gillet
- Namur Research Institute for Life Sciences (NARILIS), Integrated Veterinary Research Unit (URVI), University of Namur, Namur, Belgium
| | - Murielle Masson
- Biothechnology Superior School, UMR 7242, CNRS, University of Strasbourg, 67412 Illkirch, France
| | - Michael Herfs
- Laboratory of Experimental Pathology, GIGA-Cancer, University of Liege, 4000 Liege, Belgium
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9
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Fontan CT, Prabhakar AT, Wang X, Karimi E, Bristol ML, James CD, Morgan IM. Human papillomavirus 16 E2 blocks cellular senescence in response to activation of the DNA damage response. Virology 2022; 575:54-62. [PMID: 36058086 DOI: 10.1016/j.virol.2022.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 11/21/2022]
Abstract
Following infection by HPV16, the viral proteins E1 and E2 induce viral genome replication in association with host factors. Here we demonstrate that E2 also plays a role in promoting short-term cellular proliferation in the presence of an active DDR. Cisplatin treatment of E2 expressing cells results in short-term proliferation likely due to a block of cellular senescence and apoptosis. However, long-term growth of E2 expressing cells following cisplatin treatment is attenuated due to an accumulation of DNA damage. We discuss a possible role for this E2 function during the viral life cycle. It is also notable that E2 expressing HPV16 positive cancers have a better clinical outcome than non-E2 expressing tumors. While there are a variety of reasons for the better outcome of patients with E2 expressing tumors, this report suggests that E2 regulation of the DNA damage response may be a contributory factor.
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Affiliation(s)
- Christian T Fontan
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Apurva T Prabhakar
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Xu Wang
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Elmira Karimi
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Molly L Bristol
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Claire D James
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Iain M Morgan
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA; VCU Massey Cancer Center, Richmond, Virginia, USA.
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10
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Baedyananda F, Sasivimolrattana T, Chaiwongkot A, Varadarajan S, Bhattarakosol P. Role of HPV16 E1 in cervical carcinogenesis. Front Cell Infect Microbiol 2022; 12:955847. [PMID: 35967849 PMCID: PMC9368317 DOI: 10.3389/fcimb.2022.955847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 07/06/2022] [Indexed: 12/12/2022] Open
Abstract
Cervical cancer is the fourth most common cancer in women worldwide. More than 90% of cases are caused by the human papillomavirus (HPV). Vaccines developed only guard against a few HPV types and do not protect people who have already been infected. HPV is a small DNA virus that infects the basal layer of the stratified epithelium of the skin and mucosa through small breaks and replicates as the cells differentiate. The mucosal types of HPV can be classified into low-risk and high-risk groups, based on their association with cancer. Among HPV types in high-risk group, HPV type 16 (HPV-16) is the most common, causing 50% of all cancer cases. HPV infection can occur as transient or persistent infections, based on the ability of immune system to clear the virus. Persistent infection is characterized by the integration of HPV genome. HPV-16 exhibits a different integration pattern, with only 50% reported to be integrated at the carcinoma stage. Replication of the HPV genome depends on protein E1, an ATP-dependent helicase. E1 is essential for the amplification of the viral episome in infected cells. Previous studies have shown that E1 does not only act as a helicase protein but is also involved in recruiting and interacting with other host proteins. E1 has also been deemed to drive host cell proliferation. Recent studies have emphasized the emerging role of HPV E1 in cervical carcinogenesis. In this review, a possible mechanism by which E1 drives cell proliferation and oncogenesis will be discussed.
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Affiliation(s)
- Fern Baedyananda
- Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Thanayod Sasivimolrattana
- Medical Microbiology Interdisciplinary Program, Graduate School, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Applied Medical Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Arkom Chaiwongkot
- Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Applied Medical Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Shankar Varadarajan
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Parvapan Bhattarakosol
- Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Applied Medical Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- *Correspondence: Parvapan Bhattarakosol, ;
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11
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Baral SK, Biswas P, Kaium MA, Islam MA, Dey D, Saber MA, Rahaman TI, M A, Emran TB, Hasan MN, Jeong MK, Han I, Rahman MA, Kim B. A Comprehensive Discussion in Vaginal Cancer Based on Mechanisms, Treatments, Risk Factors and Prevention. Front Oncol 2022; 12:883805. [PMID: 35924174 PMCID: PMC9341270 DOI: 10.3389/fonc.2022.883805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 06/23/2022] [Indexed: 12/27/2022] Open
Abstract
Vaginal cancer is a rare and uncommon disease that is rarely discussed. Although vaginal cancer traditionally occurs in older postmenopausal women, the incidence of high-risk human papillomavirus (HPV)-induced cancers is increasing in younger women. Cervical cancer cells contain high-risk human papillomavirus (HPV) E6 and E7 proteins and inhibiting HPV gene expression leads the cells to stop proliferating and enter senescence. As E6, and E7 protein promoted the carcinogenesis mechanism, and here not only regulate the cellular degradation of P53, and pRb but also enhances the cell proliferation along with E6 protein targets the p53 for breakdown and subsequently promote the apoptotic cell death, and DNA repair inhibition, that is indispensable to the continue the lifecycle of the HPV. As a synchronous or metachronous tumor, vaginal cancer is frequently found in combination with cervical cancer. It is uncertain what causes invasive female vaginal organ cancer. HPV type 16 is the most often isolated HPV type in female vaginal organ cancers. Due to cancer's rarity, case studies have provided the majority of etiologic findings. Many findings demonstrate that ring pessaries, chronic vaginitis, sexual behavior, birth trauma, obesity, vaginal chemical exposure, and viruses are all risk factors. Because of insufficient understanding and disease findings, we are trying to find the disease's mechanism with the available data. We also address different risk factors, therapy at various stages, diagnosis, and management of vaginal cancer in this review.
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Affiliation(s)
| | - Partha Biswas
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Science and Technology, Jashore University of Science and Technology (JUST), Jashore, Bangladesh
- ABEx Bio-Research Center, Dhaka, Bangladesh
| | - Md. Abu Kaium
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Science and Technology, Jashore University of Science and Technology (JUST), Jashore, Bangladesh
| | - Md. Aminul Islam
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Science and Technology, Jashore University of Science and Technology (JUST), Jashore, Bangladesh
| | - Dipta Dey
- Biochemistry and Molecular Biology department, Life Science faculty, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalgonj, Bangladesh
| | - Md Al Saber
- Biotechnology, University of Pécs, Medical School, Pécs, Hungary
| | - Tanjim Ishraq Rahaman
- Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalganj, Bangladesh
| | - A. M
- Department of Microbiology, Chittagong University, Chittagong, Bangladesh
| | - Talha Bin Emran
- Department of Pharmacy, Begum Gulchemonara (BGC) Trust University Bangladesh, Chittagong, Bangladesh
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Md. Nazmul Hasan
- Laboratory of Pharmaceutical Biotechnology and Bioinformatics, Department of Genetic Engineering and Biotechnology, Jashore University of Science and Technology, Jashore, Bangladesh
| | - Mi-Kyung Jeong
- Korean Medicine (KM) Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon, South Korea
| | - Ihn Han
- Plasma Bioscience Research Center, Kwangwoon University, Seoul, South Korea
| | - Md. Ataur Rahman
- Global Biotechnology & Biomedical Research Network (GBBRN), Department of Biotechnology and Genetic Engineering, Faculty of Biological Sciences, Islamic University, Kushtia, Bangladesh
- Department of Pathology, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
- Korean Medicine-Based Drug Repositioning Cancer Research Center, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Bonglee Kim
- Department of Pathology, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
- Korean Medicine-Based Drug Repositioning Cancer Research Center, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
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12
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Plasma-Enabled Smart Nanoexosome Platform as Emerging Immunopathogenesis for Clinical Viral Infection. Pharmaceutics 2022; 14:pharmaceutics14051054. [PMID: 35631640 PMCID: PMC9145689 DOI: 10.3390/pharmaceutics14051054] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/08/2022] [Accepted: 05/11/2022] [Indexed: 02/01/2023] Open
Abstract
Smart nanoexosomes are nanosized structures enclosed in lipid bilayers that are structurally similar to the viruses released by a variety of cells, including the cells lining the respiratory system. Of particular importance, the interaction between smart nanoexosomes and viruses can be used to develop antiviral drugs and vaccines. It is possible that nanoexosomes will be utilized and antibodies will be acquired more successfully for the transmission of an immune response if reconvalescent plasma (CP) is used instead of reconvalescent plasma exosomes (CPExo) in this concept. Convalescent plasma contains billions of smart nanoexosomes capable of transporting a variety of molecules, including proteins, lipids, RNA and DNA among other viral infections. Smart nanoexosomes are released from virus-infected cells and play an important role in mediating communication between infected and uninfected cells. Infections use the formation, production and release of smart nanoexosomes to enhance the infection, transmission and intercellular diffusion of viruses. Cell-free smart nanoexosomes produced by mesenchymal stem cells (MSCs) could also be used as cell-free therapies in certain cases. Smart nanoexosomes produced by mesenchymal stem cells can also promote mitochondrial function and heal lung injury. They can reduce cytokine storms and restore the suppression of host antiviral defenses weakened by viral infections. This study examines the benefits of smart nanoexosomes and their roles in viral transmission, infection, treatment, drug delivery and clinical applications. We also explore some potential future applications for smart nanoexosomes in the treatment of viral infections.
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Yu J, Zhang W, Huo W, Meng X, Zhong T, Su Y, Liu Y, Liu J, Wang Z, Song F, Zhang S, Li Z, Yu X, Yu X, Hua S. Regulation of host factor γ-H2AX level and location by enterovirus A71 for viral replication. Virulence 2022; 13:241-257. [PMID: 35067196 PMCID: PMC8786350 DOI: 10.1080/21505594.2022.2028482] [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] [Indexed: 11/09/2022] Open
Abstract
Numerous viruses manipulate host factors for viral production. We demonstrated that human enterovirus A71 (EVA71), a primary causative agent for hand, foot, and mouth disease (HFMD), increased the level of the DNA damage response (DDR) marker γ-H2AX. DDR is primarily mediated by the ataxia telangiectasia mutated (ATM), ATM and Rad3-related (ATR), or DNA-dependent protein kinase (DNA-PK) pathways. Upregulation of γ-H2AX by EVA71 was dependent on the ATR but not the ATM or DNA-PK pathway. As a nuclear factor, there is no previous evidence of cytoplasmic distribution of γ-H2AX. However, the present findings demonstrated that EVA71 encouraged the localization of γ-H2AX to the cytoplasm. Of note, γ-H2AX formed a complex with structural protein VP3, non-structural protein 3D, and the viral genome. Treatment with an inhibitor or CRISPR/Cas9 technology to decrease or silence the expression of γ-H2AX decreased viral genome replication in host cells; this effect was accompanied by decreased viral protein expression and virions. In animal experiments, caffeine was used to inhibit DDR; the results revealed that caffeine protected neonatal mice from death after infection with EVA71, laying the foundation for new therapeutic applications of caffeine. More importantly, in children with HFMD, γ-H2AX was upregulated in peripheral blood lymphocytes. The consistent in vitro and in vivo data on γ-H2AX from this study suggested that caffeine or other inhibitors of DDR might be novel therapeutic agents for HFMD.
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Affiliation(s)
- Jinghua Yu
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Wenyan Zhang
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Wenbo Huo
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Xiangling Meng
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Ting Zhong
- Medicinal Chemistry, College of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
| | - Ying Su
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Yumeng Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Jinming Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Zengyan Wang
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Fengmei Song
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Shuxia Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Zhaolong Li
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Xiaoyan Yu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Xiaofang Yu
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Shucheng Hua
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
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14
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Baedyananda F, Chaiwongkot A, Varadarajan S, Bhattarakosol P. HPV16 E1 dysregulated cellular genes involved in cell proliferation and host DNA damage: A possible role in cervical carcinogenesis. PLoS One 2021; 16:e0260841. [PMID: 34968392 PMCID: PMC8717967 DOI: 10.1371/journal.pone.0260841] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 11/17/2021] [Indexed: 12/28/2022] Open
Abstract
HPV16 is the most prominent cause of cervical cancer. HPV16 E1, a helicase required for HPV replication exhibits increased expression in association with cervical cancer progression, suggesting that E1 has a similar effect on the host as the HPV16 E6 and E7 oncoproteins. This study aimed to determine whether expression of HPV16 E1 correlated with carcinogenesis by modulating cellular pathways involved in cervical cancer. HEK293T cells were transfected with pEGFP, pEGFPE1 or truncated forms of HPV16 E1. Cell proliferation, cell death, and the impact of HPV16 E1 on host gene expression was then evaluated. HPV16 E1 overexpression resulted in a significant reduction of cell viability and cellular proliferation (p-value<0.0001). Moreover, prolonged expression of HPV16 E1 significantly induced both apoptotic and necrotic cell death, which was partially inhibited by QVD-OPH, a broad-spectrum caspase inhibitor. Microarray, real time RT-PCR and kinetic host gene expression analyses revealed that HPV16 E1 overexpression resulted in the downregulation of genes involved in protein synthesis (RPL36A), metabolism (ALDOC), cellular proliferation (CREB5, HIF1A, JMJDIC, FOXO3, NFKB1, PIK3CA, TSC22D3), DNA damage (ATR, BRCA1 and CHEK1) and immune response (ISG20) pathways. How these genetic changes contribute to HPV16 E1-mediated cervical carcinogenesis warrants further studies.
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Affiliation(s)
- Fern Baedyananda
- Applied Medical Virology Research Unit, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Arkom Chaiwongkot
- Applied Medical Virology Research Unit, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Shankar Varadarajan
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Parvapan Bhattarakosol
- Applied Medical Virology Research Unit, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- Division of Virology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
- * E-mail:
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15
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Wang L, Wang F, Fu S, Zhang C, Zhe X, Li H, Li D, Shao R, Pan Z. Analysis of genetic variation in human papillomavirus type 16 E1 and E2 in women with cervical infection in Xinjiang, China. BMC Med Genomics 2021; 14:268. [PMID: 34772425 PMCID: PMC8590209 DOI: 10.1186/s12920-021-01120-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 11/02/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Xinjiang is one of the regions with a high incidence of cervical cancer, and the genetic variation of human papillomavirus may increase its ability to infect the human body and enhance virus-mediated immune escape ability. METHODS Sanger sequencing of the HPV16 genome from 165 samples positive for HPV16 infection and phylogenetic analysis of the E1 and E2 genes revealed the gene polymorphism of HPV16 in Xinjiang. RESULTS The results showed that there were 109 samples with variations in HPV16 E1, 48 sites with nucleotide variations (19 missense variations and 29 synonymous variations), and 91 samples with variations in HPV16 E2, 25 sites with nucleotide variations (20 missense variations and five synonymous variations). CONCLUSIONS From the phylogenetic tree results, 149 samples were of the European variant and 16 samples were of the Asian variant. No African or North American/Asian variant types were found.
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Affiliation(s)
- Luyue Wang
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China
| | - Fang Wang
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China
| | - Shaowei Fu
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China
| | - Chunhe Zhang
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China
| | - Xiangyi Zhe
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China
| | - Hongtao Li
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China
| | - Dongmei Li
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China.
| | - Renfu Shao
- School of Science, Technology and Engineering, Genecology Research Centre, University of the Sunshine Coast, Sippy Downs, QLD, 4556, Australia
| | - Zemin Pan
- Department of Biochemistry and Molecular Biology, School of Medicine, Xinjiang Endemic and Ethnic Disease and Education Ministry Key Laboratory, Shihezi University, Shihezi, 832002, Xinjiang, People's Republic of China.
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Spatial and Functional Organization of Human Papillomavirus Replication Foci in the Productive Stage of Infection. mBio 2021; 12:e0268421. [PMID: 34749533 PMCID: PMC8576538 DOI: 10.1128/mbio.02684-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The life cycle of human papillomavirus (HPV) depends on keratinocyte differentiation as the virus modulates and takes advantage of cellular pathways to replicate its genome and assemble viral particles in differentiated cells. Viral genomes are amplified in nuclear replication foci in differentiated keratinocytes, and DNA repair factors from the DNA damage response signaling pathway are recruited to replicate viral DNA. The HPV genome is associated with cellular histones at all stages of the infectious cycle, and here, we show that the histone variant macroH2A1 is bound to the HPV genome and enriched in viral replication foci in differentiated cells. macroH2A1 isoforms play important roles in cellular transcriptional repression, double-strand break repair, and replication stress. The viral E8^E2 protein also binds to the HPV genome and inhibits viral replication and gene expression by recruiting NCoR/SMRT complexes. We show here that E8^E2 and SMRT also localize within replication foci, though independently from macroH2A1. Conversely, transcription complexes containing RNA polymerase II and Brd4 are located on the surface of the foci. Foci generated with an HPV16 E8^E2 mutant genome are not enriched for SMRT or macroH2A1 but contain transcriptional complexes throughout the foci. We propose that both the cellular macroH2A1 protein and viral E8^E2 protein help to spatially separate replication and transcription activities within viral replication foci. IMPORTANCE Human papillomaviruses are small DNA viruses that cause chronic infection of cutaneous and mucosal epithelium. In some cases, persistent infection with HPV can result in cancer, and 5% of human cancers are the result of HPV infection. In differentiated cells, HPV amplifies viral DNA in nuclear replication factories and transcribes late mRNAs to produce capsid proteins. However, very little is known about the spatial organization of these activities in the nucleus. Here, we show that repressive viral and cellular factors localize within the foci to suppress viral transcription, while active transcription takes place on the surface. The cellular histone variant macroH2A1 is important for this spatial organization.
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17
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Hussain SS, Lundine D, Leeman JE, Higginson DS. Genomic Signatures in HPV-Associated Tumors. Viruses 2021; 13:v13101998. [PMID: 34696429 PMCID: PMC8537705 DOI: 10.3390/v13101998] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 09/30/2021] [Accepted: 10/02/2021] [Indexed: 02/01/2023] Open
Abstract
Papillomaviruses dysregulate the G1/S cell cycle transition in order to promote DNA synthesis in S phase, which is a requirement for viral replication. The human papillomaviruses (HPV) E6 and E7 oncoproteins mediate degradation of the cell cycle regulators p53 and Rb, which are two of the most universally disrupted tumor-suppressor genes in all of cancer. The G1/S checkpoint is activated in normal cells to allow sufficient time for DNA repair in G1 before proceeding to replicate DNA and risk propagating unrepaired errors. The TP53 pathway suppresses a variety of such errors, including translocation, copy number alterations, and aneuploidy, which are thus found in HPV-associated tumors similarly to HPV-negative tumors with other mechanisms of TP53 disruption. However, E6 and E7 maintain a variety of other virus–host interactions that directly disrupt a growing list of other DNA repair and chromatin remodeling factors, implying HPV-specific repair deficiencies. In addition, HPV-associated squamous cell carcinomas tumors clinically respond differently to DNA damaging agents compared to their HPV negative counterparts. The focus of this review is to integrate three categories of observations: (1) pre-clinical understanding as to the effect of HPV on DNA repair, (2) genomic signatures of DNA repair in HPV-associated tumor genomes, and (3) clinical responses of HPV-associated tumors to DNA damaging agents. The goals are to try to explain why HPV-associated tumors respond so well to DNA damaging agents, identify missing pieces, and suggest clinical strategies could be used to further improve treatment of these cancers.
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Affiliation(s)
- Suleman S. Hussain
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (S.S.H.); (D.L.)
| | - Devon Lundine
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (S.S.H.); (D.L.)
| | - Jonathan E. Leeman
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02189, USA;
| | - Daniel S. Higginson
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (S.S.H.); (D.L.)
- Correspondence:
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Warburton A, Della Fera AN, McBride AA. Dangerous Liaisons: Long-Term Replication with an Extrachromosomal HPV Genome. Viruses 2021; 13:1846. [PMID: 34578427 PMCID: PMC8472234 DOI: 10.3390/v13091846] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 01/17/2023] Open
Abstract
Papillomaviruses cause persistent, and usually self-limiting, infections in the mucosal and cutaneous surfaces of the host epithelium. However, in some cases, infection with an oncogenic HPV can lead to cancer. The viral genome is a small, double-stranded circular DNA molecule that is assembled into nucleosomes at all stages of infection. The viral minichromosome replicates at a low copy number in the nucleus of persistently infected cells using the cellular replication machinery. When the infected cells differentiate, the virus hijacks the host DNA damage and repair pathways to replicate viral DNA to a high copy number to generate progeny virions. This strategy is highly effective and requires a close association between viral and host chromatin, as well as cellular processes associated with DNA replication, repair, and transcription. However, this association can lead to accidental integration of the viral genome into host DNA, and under certain circumstances integration can promote oncogenesis. Here we describe the fate of viral DNA at each stage of the viral life cycle and how this might facilitate accidental integration and subsequent carcinogenesis.
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Affiliation(s)
| | | | - Alison A. McBride
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; (A.W.); (A.N.D.F.)
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19
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McBride AA, Warburton A, Khurana S. Multiple Roles of Brd4 in the Infectious Cycle of Human Papillomaviruses. Front Mol Biosci 2021; 8:725794. [PMID: 34386523 PMCID: PMC8353396 DOI: 10.3389/fmolb.2021.725794] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/14/2021] [Indexed: 12/17/2022] Open
Abstract
Human Papillomaviruses (HPV) reproduce in stratified epithelia by establishing a reservoir of low- level infection in the dividing basal cells and restricting the production of viral particles to terminally differentiated cells. These small DNA viruses hijack pivotal cellular processes and pathways to support the persistent infectious cycle. One cellular factor that is key to multiple stages of viral replication and transcription is the BET (bromodomain and extra-terminal domain) protein, Brd4 (Bromodomain containing protein 4). Here we provide an overview of the multiple interactions of Brd4 that occur throughout the HPV infectious cycle.
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Affiliation(s)
- Alison A. McBride
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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20
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Regulation of HPV18 Genome Replication, Establishment and Persistence by Sequences in the Viral Upstream Regulatory Region. J Virol 2021; 95:e0068621. [PMID: 34232709 DOI: 10.1128/jvi.00686-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During persistent human papillomavirus infection, the viral genome replicates as an extrachromosomal plasmid that is efficiently partitioned to daughter cells during cell division. We have previously shown that an element which overlaps the HPV18 transcriptional enhancer promotes stable DNA replication of replicons containing the viral replication origin. Here we perform comprehensive analyses to elucidate the function of this maintenance element. We conclude that no unique element or binding site in this region is absolutely required for persistent replication and partitioning, and instead propose that the overall chromatin architecture of this region is important to promote efficient use of the replication origin. These results have important implications on the genome partitioning mechanism of papillomaviruses. Importance Persistent infection with oncogenic HPVs is responsible for ∼5% human cancers. The viral DNA replicates as an extrachromosomal plasmid and is partitioned to daughter cells in dividing keratinocytes. Using a complementation assay that allows us to separate viral transcription and replication, we provide insight into viral sequences that are required for long term replication and persistence in keratinocytes. Understanding how viral genomes replicate persistently for such long periods of time will guide the development of anti-viral therapies.
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21
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Vats A, Trejo-Cerro O, Thomas M, Banks L. Human papillomavirus E6 and E7: What remains? Tumour Virus Res 2021; 11:200213. [PMID: 33716206 PMCID: PMC7972986 DOI: 10.1016/j.tvr.2021.200213] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
Decades of research on the human papillomavirus oncogenes, E6 and E7, have given us huge amounts of data on their expression, functions and structures. We know much about the very many cellular proteins and pathways that they influence in one way or another. However, much of this information is quite discrete, referring to one activity examined under one condition. It is now time to join the dots to try to understand a larger picture: how, where and when do all these interactions occur... and why? Examining these questions will also show how many of the yet obscure cellular processes work together for cellular and tissue homeostasis in health and disease.
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Affiliation(s)
- Arushi Vats
- Tumour Virology Group, ICGEB, AREA Science Park, Trieste, 34149, Italy
| | - Oscar Trejo-Cerro
- Tumour Virology Group, ICGEB, AREA Science Park, Trieste, 34149, Italy
| | - Miranda Thomas
- Tumour Virology Group, ICGEB, AREA Science Park, Trieste, 34149, Italy.
| | - Lawrence Banks
- Tumour Virology Group, ICGEB, AREA Science Park, Trieste, 34149, Italy
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22
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Pathogenic Role of Immune Evasion and Integration of Human Papillomavirus in Oropharyngeal Cancer. Microorganisms 2021; 9:microorganisms9050891. [PMID: 33919460 PMCID: PMC8143538 DOI: 10.3390/microorganisms9050891] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023] Open
Abstract
The incidence of oropharyngeal cancer (OPC) is increasing remarkably among all head and neck cancers, mainly due to its association with the human papillomavirus (HPV). Most HPVs are eliminated by the host’s immune system; however, because HPV has developed an effective immune evasion mechanism to complete its replication cycle, a small number of HPVs are not eliminated, leading to persistent infection. Moreover, during the oncogenic process, the extrachromosomal HPV genome often becomes integrated into the host genome. Integration involves the induction and high expression of E6 and E7, leading to cell cycle activation and increased genomic instability in the host. Therefore, integration is an important event in oncogenesis, although the associated mechanism remains unclear, especially in HPV-OPC. In this review, we summarize the current knowledge on HPV-mediated carcinogenesis, with special emphasis on immune evasion and integration mechanisms, which are crucial for oncogenesis.
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23
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EXPRESSION OF E8^E2 IS REQUIRED FOR WART FORMATION BY MOUSE PAPILLOMAVIRUS 1 IN VIVO. J Virol 2021; 95:JVI.01930-20. [PMID: 33472931 PMCID: PMC8103706 DOI: 10.1128/jvi.01930-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Human papillomavirus (HPV) E1 and E2 proteins activate genome replication. E2 also modulates viral gene expression and is involved in the segregation of viral genomes. In addition to full length E2, almost all PV share the ability to encode an E8^E2 protein, that is a fusion of E8 with the C-terminal half of E2 which mediates specific DNA-binding and dimerization. HPV E8^E2 acts as a repressor of viral gene expression and genome replication. To analyze the function of E8^E2 in vivo, we used the Mus musculus PV1 (MmuPV1)-mouse model system. Characterization of the MmuPV1 E8^E2 protein revealed that it inhibits transcription from viral promoters in the absence and presence of E1 and E2 proteins and that this is partially dependent upon the E8 domain. MmuPV1 genomes, in which the E8 ATG start codon was disrupted (E8-), displayed a 10- to 25-fold increase in viral gene expression compared to wt genomes in cultured normal mouse tail keratinocytes in short-term experiments. This suggests that the function and mechanism of E8^E2 is conserved between MmuPV1 and HPVs. Surprisingly, challenge of athymic nude Foxn1nu/nu mice with MmuPV1 E8- genomes did not induce warts on the tail in contrast to wt MmuPV1. Furthermore, viral gene expression was completely absent at E8- MmuPV1 sites 20 - 22 weeks after DNA challenge on the tail or quasivirus challenge in the vaginal vault. This reveals that expression of E8^E2 is necessary to form tumors in vivo and that this is independent from the presence of T-cells.IMPORTANCE HPV encode an E8^E2 protein which acts as repressors of viral gene expression and genome replication. In cultured normal keratinocytes, E8^E2 is essential for long-term episomal maintenance of HPV31 genomes, but not for HPV16. To understand E8^E2's role in vivo, the Mus musculus PV1 (MmuPV1)-mouse model system was used. This revealed that E8^E2's function as a repressor of viral gene expression is conserved. Surprisingly, MmuPV1 E8^E2 knock out genomes did not induce warts in T-cell deficient mice. This shows for the first time that expression of E8^E2 is necessary for tumor formation in vivo independently of T cell immunity. This indicates that E8^E2 could be an interesting target for anti-viral therapy in vivo.
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Della Fera AN, Warburton A, Coursey TL, Khurana S, McBride AA. Persistent Human Papillomavirus Infection. Viruses 2021; 13:v13020321. [PMID: 33672465 PMCID: PMC7923415 DOI: 10.3390/v13020321] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 02/16/2021] [Accepted: 02/17/2021] [Indexed: 12/16/2022] Open
Abstract
Simple Summary The success of HPV as an infectious agent lies not within its ability to cause disease, but rather in the adeptness of the virus to establish long-term persistent infection. The ability of HPV to replicate and maintain its genome in a stratified epithelium is contingent on the manipulation of many host pathways. HPVs must abrogate host anti-viral defense programs, perturb the balance of cellular proliferation and differentiation, and hijack DNA damage signaling and repair pathways to replicate viral DNA in a stratified epithelium. Together, these characteristics contribute to the ability of HPV to achieve long-term and persistent infection and to its evolutionary success as an infectious agent. Abstract Persistent infection with oncogenic human papillomavirus (HPV) types is responsible for ~5% of human cancers. The HPV infectious cycle can sustain long-term infection in stratified epithelia because viral DNA is maintained as low copy number extrachromosomal plasmids in the dividing basal cells of a lesion, while progeny viral genomes are amplified to large numbers in differentiated superficial cells. The viral E1 and E2 proteins initiate viral DNA replication and maintain and partition viral genomes, in concert with the cellular replication machinery. Additionally, the E5, E6, and E7 proteins are required to evade host immune responses and to produce a cellular environment that supports viral DNA replication. An unfortunate consequence of the manipulation of cellular proliferation and differentiation is that cells become at high risk for carcinogenesis.
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Hirose Y, Yamaguchi-Naka M, Onuki M, Tenjimbayashi Y, Tasaka N, Satoh T, Tanaka K, Iwata T, Sekizawa A, Matsumoto K, Kukimoto I. High Levels of Within-Host Variations of Human Papillomavirus 16 E1/E2 Genes in Invasive Cervical Cancer. Front Microbiol 2020; 11:596334. [PMID: 33324377 PMCID: PMC7721666 DOI: 10.3389/fmicb.2020.596334] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/22/2020] [Indexed: 12/01/2022] Open
Abstract
Human papillomavirus type 16 (HPV16) is the most common HPV genotype found in invasive cervical cancer (ICC). Recent comprehensive genomics studies of HPV16 have revealed that a large number of minor nucleotide variations in the viral genome are present in each infected woman; however, it remains unclear whether such within-host variations of HPV16 are linked to cervical carcinogenesis. Here, by employing next-generation sequencing approaches, we explored the mutational profiles of the HPV16 genome within individual clinical specimens from ICC (n = 31) and normal cervix (n = 21) in greater detail. A total of 367 minor nucleotide variations (167 from ICC and 200 from the normal cervix) were detected throughout the viral genome in both groups, while nucleotide variations at high frequencies (>10% abundance in relative read counts in a single sample) were more prevalent in ICC (10 in ICC versus 1 in normal). Among the high-level variations found in ICC, six were located in the E1/E2 genes, and all of them were non-synonymous substitutions (Q142K, M207I, and L262V for E1; D153Y, R302T, and T357A for E2). In vitro functional analyses of these E1/E2 variants revealed that E1/M207I, E2/D153Y, and E2/R302T had reduced abilities to support viral replication, and that E2/D153Y and E2/R302T failed to suppress the viral early promoter. These results imply that some within-host variations of E1/E2 present at high levels in ICC may be positively selected for and contribute to cervical cancer development through dysfunction or de-stabilization of viral replication/transcription proteins.
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Affiliation(s)
- Yusuke Hirose
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan
| | - Mayuko Yamaguchi-Naka
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan
| | - Mamiko Onuki
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan
| | - Yuri Tenjimbayashi
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan
| | - Nobutaka Tasaka
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Toyomi Satoh
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Kohsei Tanaka
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Takashi Iwata
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan
| | - Akihiko Sekizawa
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan
| | - Koji Matsumoto
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan
| | - Iwao Kukimoto
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan
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Das D, Bristol ML, Pichierri P, Morgan IM. Using a Human Papillomavirus Model to Study DNA Replication and Repair of Wild Type and Damaged DNA Templates in Mammalian Cells. Int J Mol Sci 2020; 21:E7564. [PMID: 33066318 PMCID: PMC7589113 DOI: 10.3390/ijms21207564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/06/2020] [Accepted: 10/12/2020] [Indexed: 12/13/2022] Open
Abstract
Human papillomaviruses have 8kbp DNA episomal genomes that replicate autonomously from host DNA. During initial infection, the virus increases its copy number to 20-50 copies per cell, causing torsional stress on the replicating DNA. This activates the DNA damage response (DDR) and HPV replicates its genome, at least in part, using homologous recombination. An active DDR is on throughout the HPV life cycle. Two viral proteins are required for replication of the viral genome; E2 binds to 12bp palindromic sequences around the A/T rich origin of replication and recruits the viral helicase E1 via a protein-protein interaction. E1 forms a di-hexameric complex that replicates the viral genome in association with host factors. Transient replication assays following transfection with E1-E2 expression plasmids, along with an origin containing plasmid, allow monitoring of E1-E2 replication activity. Incorporating a bacterial lacZ gene into the origin plasmid allows for the determination of replication fidelity. Here we describe how we exploited this system to investigate replication and repair in mammalian cells, including using damaged DNA templates. We propose that this system has the potential to enhance the understanding of cellular components involved in DNA replication and repair.
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Affiliation(s)
- Dipon Das
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, VA 23298, USA; (D.D.); (M.L.B.)
| | - Molly L. Bristol
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, VA 23298, USA; (D.D.); (M.L.B.)
| | - Pietro Pichierri
- Department of Environment and Health, Istituto Superiore di Sanita’, 00161 Rome, Italy;
| | - Iain M. Morgan
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, VA 23298, USA; (D.D.); (M.L.B.)
- VCU Massey Cancer Center, Richmond, VA 23298, USA
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James CD, Das D, Morgan EL, Otoa R, Macdonald A, Morgan IM. Werner Syndrome Protein (WRN) Regulates Cell Proliferation and the Human Papillomavirus 16 Life Cycle during Epithelial Differentiation. mSphere 2020; 5:e00858-20. [PMID: 32938703 PMCID: PMC7494838 DOI: 10.1128/msphere.00858-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 09/01/2020] [Indexed: 12/13/2022] Open
Abstract
Human papillomaviruses recruit a host of DNA damage response factors to their viral genome to facilitate homologous recombination replication in association with the viral replication factors E1 and E2. We previously demonstrated that SIRT1 deacetylation of WRN promotes recruitment of WRN to E1-E2 replicating DNA and that WRN regulates both the levels and fidelity of E1-E2 replication. The deacetylation of WRN by SIRT1 results in an active protein able to complex with replicating DNA, but a protein that is less stable. Here, we demonstrate an inverse correlation between SIRT1 and WRN in CIN cervical lesions compared to normal control tissue, supporting our model of SIRT1 deacetylation destabilizing WRN protein. We CRISPR/Cas9 edited N/Tert-1 and N/Tert-1+HPV16 cells to knock out WRN protein expression and subjected the cells to organotypic raft cultures. In N/Tert-1 cells without WRN expression, there was enhanced basal cell proliferation, DNA damage, and thickening of the differentiated epithelium. In N/Tert-1+HPV16 cells, there was enhanced basal cell proliferation, increased DNA damage throughout the epithelium, and increased viral DNA replication. Overall, the results demonstrate that the expression of WRN is required to control the proliferation of N/Tert-1 cells and controls the HPV16 life cycle in these cells. This complements our previous data demonstrating that WRN controls the levels and fidelity of HPV16 E1-E2 DNA replication. The results describe a new role for WRN, a tumor suppressor, in controlling keratinocyte differentiation and the HPV16 life cycle.IMPORTANCE HPV16 is the major human viral carcinogen, responsible for around 3 to 4% of all cancers worldwide. Our understanding of how the viral replication machinery interacts with host factors to control/activate the DNA damage response to promote the viral life cycle remains incomplete. Recently, we demonstrated a SIRT1-WRN axis that controls HPV16 replication, and here we demonstrate that this axis persists in clinical cervical lesions induced by HPV16. Here, we describe the effects of WRN depletion on cellular differentiation with or without HPV16; WRN depletion results in enhanced proliferation and DNA damage irrespective of HPV16 status. Also, WRN is a restriction factor for the viral life cycle since replication is disrupted in the absence of WRN. Future studies will focus on enhancing our understanding of how WRN regulates viral replication. Our goal is to ultimately identify cellular factors essential for HPV16 replication that can be targeted for therapeutic gain.
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Affiliation(s)
- Claire D James
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Dipon Das
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Ethan L Morgan
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Raymonde Otoa
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
| | - Andrew Macdonald
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Iain M Morgan
- Virginia Commonwealth University (VCU), Philips Institute for Oral Health Research, School of Dentistry, Richmond, Virginia, USA
- VCU Massey Cancer Center, Richmond, Virginia, USA
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The Role of Ataxia Telangiectasia Mutant and Rad3-Related DNA Damage Response in Pathogenesis of Human Papillomavirus. Pathogens 2020; 9:pathogens9060506. [PMID: 32585979 PMCID: PMC7350315 DOI: 10.3390/pathogens9060506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 12/16/2022] Open
Abstract
Human papillomavirus (HPV) infection leads to a variety of benign lesions and malignant tumors such as cervical cancer and head and neck squamous cell carcinoma. Several HPV vaccines have been developed that can help to prevent cervical carcinoma, but these vaccines are only effective in individuals with no prior HPV infection. Thus, it is still important to understand the HPV life cycle and in particular the association of HPV with human pathogenesis. HPV production requires activation of the DNA damage response (DDR), which is a complex signaling network composed of multiple sensors, mediators, transducers, and effectors that safeguard cellular DNAs to maintain the host genome integrity. In this review, we focus on the roles of the ataxia telangiectasia mutant and Rad3-related (ATR) DNA damage response in HPV DNA replication. HPV can induce ATR expression and activate the ATR pathway. Inhibition of the ATR pathway results in suppression of HPV genome maintenance and amplification. The mechanisms underlying this could be through various molecular pathways such as checkpoint signaling and transcriptional regulation. In light of these findings, other downstream mechanisms of the ATR pathway need to be further investigated for better understanding HPV pathogenesis and developing novel ATR DDR-related inhibitors against HPV infection.
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Epigenetic Regulation of the Human Papillomavirus Life Cycle. Pathogens 2020; 9:pathogens9060483. [PMID: 32570816 PMCID: PMC7350343 DOI: 10.3390/pathogens9060483] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 12/20/2022] Open
Abstract
Persistent infection with certain types of human papillomaviruses (HPVs), termed high risk, presents a public health burden due to their association with multiple human cancers, including cervical cancer and an increasing number of head and neck cancers. Despite the development of prophylactic vaccines, the incidence of HPV-associated cancers remains high. In addition, no vaccine has yet been licensed for therapeutic use against pre-existing HPV infections and HPV-associated diseases. Although persistent HPV infection is the major risk factor for cancer development, additional genetic and epigenetic alterations are required for progression to the malignant phenotype. Unlike genetic mutations, the reversibility of epigenetic modifications makes epigenetic regulators ideal therapeutic targets for cancer therapy. This review article will highlight the recent advances in the understanding of epigenetic modifications associated with HPV infections, with a particular focus on the role of these epigenetic changes during different stages of the HPV life cycle that are closely associated with activation of DNA damage response pathways.
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James CD, Das D, Bristol ML, Morgan IM. Activating the DNA Damage Response and Suppressing Innate Immunity: Human Papillomaviruses Walk the Line. Pathogens 2020; 9:E467. [PMID: 32545729 PMCID: PMC7350329 DOI: 10.3390/pathogens9060467] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 12/25/2022] Open
Abstract
Activation of the DNA damage response (DDR) by external agents can result in DNA fragments entering the cytoplasm and activating innate immune signaling pathways, including the stimulator of interferon genes (STING) pathway. The consequences of this activation can result in alterations in the cell cycle including the induction of cellular senescence, as well as boost the adaptive immune response following interferon production. Human papillomaviruses (HPV) are the causative agents in a host of human cancers including cervical and oropharyngeal; HPV are responsible for around 5% of all cancers. During infection, HPV replication activates the DDR in order to promote the viral life cycle. A striking feature of HPV-infected cells is their ability to continue to proliferate in the presence of an active DDR. Simultaneously, HPV suppress the innate immune response using a number of different mechanisms. The activation of the DDR and suppression of the innate immune response are essential for the progression of the viral life cycle. Here, we describe the mechanisms HPV use to turn on the DDR, while simultaneously suppressing the innate immune response. Pushing HPV from this fine line and tipping the balance towards activation of the innate immune response would be therapeutically beneficial.
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Affiliation(s)
- Claire D. James
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, VA 23298, USA; (C.D.J.); (D.D.); (M.L.B.)
| | - Dipon Das
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, VA 23298, USA; (C.D.J.); (D.D.); (M.L.B.)
| | - Molly L. Bristol
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, VA 23298, USA; (C.D.J.); (D.D.); (M.L.B.)
| | - Iain M. Morgan
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University (VCU), Richmond, VA 23298, USA; (C.D.J.); (D.D.); (M.L.B.)
- VCU Massey Cancer Center, Richmond, VA 23298, USA
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James CD, Fontan CT, Otoa R, Das D, Prabhakar AT, Wang X, Bristol ML, Morgan IM. Human Papillomavirus 16 E6 and E7 Synergistically Repress Innate Immune Gene Transcription. mSphere 2020; 5:e00828-19. [PMID: 31915229 PMCID: PMC6952203 DOI: 10.1128/msphere.00828-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 12/12/2019] [Indexed: 11/22/2022] Open
Abstract
Human papillomaviruses (HPV) are causative agents in 5% of all cancers, including the majority of anogenital and oropharyngeal cancers. Downregulation of innate immune genes (IIGs) by HPV to promote the viral life cycle is well documented; E6 and E7 are known repressors of these genes. More recently, we demonstrated that E2 could also repress IIGs. These studies have been carried out in cells overexpressing the viral proteins, and to further investigate the role of individual viral proteins in this repression, we introduced stop codons into E6 and/or E7 in the entire HPV16 genome and generated N/Tert-1 cells stably maintaining the HPV16 genomes. We demonstrate that E6 or E7 individually is not sufficient to repress IIG expression in the context of the entire HPV16 genome; both are required for a synergistic repression. The DNA damage response (DDR) is activated by HPV16 irrespective of E6 and E7 expression, presumably due to viral replication; E1 is a known activator of the DDR. In addition, replication stress was apparent in HPV16-positive cells lacking E6 and E7, manifested by attenuated cellular growth and activation of replication stress genes. These studies led us to the following model. Viral replication per se can activate the DDR following infection, and this activation is a known inducer of IIG expression, which may induce cellular senescence. To combat this, E6 and E7 synergistically combine to manipulate the DDR and actively repress innate immune gene expression promoting cellular growth; neither protein by itself is able to do this.IMPORTANCE The role of human papillomavirus 16 (HPV16) in human cancers is well established; however, to date there are no antiviral therapeutics that are available for combatting these cancers. To identify such targets, we must enhance the understanding of the viral life cycle. Innate immune genes (IIGs) are repressed by HPV16, and we have reported that this repression persists through to cancer. Reversal of this repression would boost the immune response to HPV16-positive tumors, an area that is becoming more important given the advances in immunotherapy. This report demonstrates that E6 and E7 synergistically repress IIG expression in the context of the entire HPV16 genome. Removal of either protein activates the expression of IIGs by HPV16. Therefore, gaining a precise understanding of how the viral oncogenes repress IIG expression represents an opportunity to reverse this repression and boost the immune response to HPV16 infections for therapeutic gain.
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Affiliation(s)
- Claire D James
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Christian T Fontan
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Raymonde Otoa
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Dipon Das
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Apurva T Prabhakar
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Xu Wang
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Molly L Bristol
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Iain M Morgan
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
- Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia, USA
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Wallace NA. Catching HPV in the Homologous Recombination Cookie Jar. Trends Microbiol 2019; 28:191-201. [PMID: 31744663 DOI: 10.1016/j.tim.2019.10.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/14/2019] [Accepted: 10/17/2019] [Indexed: 12/27/2022]
Abstract
To replicate, the human papillomaviruses (HPVs) that cause anogenital and oropharyngeal malignancies must simultaneously activate DNA repair pathways and avoid the cell cycle arrest that normally accompanies DNA repair. For years it seemed that HPV oncogenes activated the homologous recombination pathway to facilitate the HPV lifecycle. However, recent developments show that, although homologous recombination gene expression and markers of pathway activation are increased, homologous recombination itself is attenuated. This review provides an overview of the diverse ways that HPV oncogenes manipulate homologous recombination and ideas on how the resulting dysregulation and inhibition offer opportunities for improved therapies and biomarkers.
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Abstract
Viral infection is a major contributor to the global cancer burden. Recent advances have revealed that seven known oncogenic viruses promote tumorigenesis through shared host cell targets and pathways. A comprehensive understanding of the principles of viral oncogenesis may enable the identification of unknown infectious aetiologies of cancer and the development of therapeutic or preventive strategies for virus-associated cancers. In this Review, we discuss the molecular mechanisms of viral oncogenesis in humans. We highlight recent advances in understanding how viral manipulation of host cellular signalling, DNA damage responses, immunity and microRNA targets promotes the initiation and development of cancer.
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Affiliation(s)
- Nathan A Krump
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jianxin You
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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SAMHD1 Regulates Human Papillomavirus 16-Induced Cell Proliferation and Viral Replication during Differentiation of Keratinocytes. mSphere 2019; 4:4/4/e00448-19. [PMID: 31391281 PMCID: PMC6686230 DOI: 10.1128/msphere.00448-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Human papillomaviruses induce a host of anogenital cancers, as well as oropharyngeal cancer (HPV+OPC); human papillomavirus 16 (HPV16) is causative in around 90% of HPV+OPC cases. Using telomerase reverse transcriptase (TERT) immortalized foreskin keratinocytes (N/Tert-1), we have identified significant host gene reprogramming by HPV16 (N/Tert-1+HPV16) and demonstrated that N/Tert-1+HPV16 support late stages of the viral life cycle. Expression of the cellular dNTPase and homologous recombination factor sterile alpha motif and histidine-aspartic domain HD-containing protein 1 (SAMHD1) is transcriptionally regulated by HPV16 in N/Tert-1. CRISPR/Cas9 removal of SAMHD1 from N/Tert-1 and N/Tert-1+HPV16 demonstrates that SAMHD1 controls cell proliferation of N/Tert-1 only in the presence of HPV16; the deletion of SAMHD1 promotes hyperproliferation of N/Tert-1+HPV16 cells in organotypic raft cultures but has no effect on N/Tert-1. Viral replication is also elevated in the absence of SAMHD1. This new system has allowed us to identify a specific interaction between SAMHD1 and HPV16 that regulates host cell proliferation and viral replication; such studies are problematic in nonimmortalized primary keratinocytes due to their limited life span. To confirm the relevance of our results, we repeated the analysis with human tonsil keratinocytes (HTK) immortalized by HPV16 (HTK+HPV16) and observed the same hyperproliferative phenotype following CRISPR/Cas9 editing of SAMHD1. Identical results were obtained with three independent CRISPR/Cas9 guide RNAs. The isogenic pairing of N/Tert-1 with N/Tert-1+HPV16, combined with HTK+HPV16, presents a unique system to identify host genes whose products functionally interact with HPV16 to regulate host cellular growth in keratinocytes.IMPORTANCE HPVs are causative agents in human cancers and are responsible for around of 5% of all cancers. A better understanding of the viral life cycle in keratinocytes will facilitate the development of novel therapeutics to combat HPV-positive cancers. Here, we present a unique keratinocyte model to identify host proteins that specifically interact with HPV16. Using this system, we report that a cellular gene, SAMHD1, is regulated by HPV16 at the RNA and protein levels in keratinocytes. Elimination of SAMHD1 from these cells using CRISPR/Cas9 editing promotes enhanced cellular proliferation by HPV16 in keratinocytes and elevated viral replication but not in keratinocytes that do not have HPV16. Our study demonstrates a specific intricate interplay between HPV16 and SAMHD1 during the viral life cycle and establishes a unique model system to assist exploring host factors critical for HPV pathogenesis.
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Abstract
Persistent viral infections require a host cell reservoir that maintains functional copies of the viral genome. To this end, several DNA viruses maintain their genomes as extrachromosomal DNA minichromosomes in actively dividing cells. These viruses typically encode a viral protein that binds specifically to viral DNA genomes and tethers them to host mitotic chromosomes, thus enabling the viral genomes to hitchhike or piggyback into daughter cells. Viruses that use this tethering mechanism include papillomaviruses and the gammaherpesviruses Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus. This review describes the advantages and consequences of persistent extrachromosomal viral genome replication.
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Affiliation(s)
- Tami L Coursey
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Alison A McBride
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA;
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Murakami I, Egawa N, Griffin H, Yin W, Kranjec C, Nakahara T, Kiyono T, Doorbar J. Roles for E1-independent replication and E6-mediated p53 degradation during low-risk and high-risk human papillomavirus genome maintenance. PLoS Pathog 2019; 15:e1007755. [PMID: 31083694 PMCID: PMC6544336 DOI: 10.1371/journal.ppat.1007755] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 05/31/2019] [Accepted: 04/08/2019] [Indexed: 01/08/2023] Open
Abstract
Human papillomaviruses (HPV) have genotype-specific disease associations, with high-risk alpha types causing at least 5% of all human cancers. Despite these conspicuous differences, our data show that high- and low- risk HPV types use similar approaches for genome maintenance and persistence. During the maintenance phase, viral episomes and the host cell genome are replicated synchronously, and for both the high- and low-risk HPV types, the E1 viral helicase is non-essential. During virus genome amplification, replication switches from an E1-independent to an E1-dependent mode, which can uncouple viral DNA replication from that of the host cell. It appears that the viral E2 protein, but not E6 and E7, is required for the synchronous maintenance-replication of both the high and the low-risk HPV types. Interestingly, the ability of the high-risk E6 protein to mediate the proteosomal degradation of p53 and to inhibit keratinocyte differentiation, was also seen with low-risk HPV E6, but in this case was regulated by cell density and the level of viral gene expression. This allows low-risk E6 to support genome amplification, while limiting the extent of E6-mediated cell proliferation during synchronous genome maintenance. Both high and low-risk E7s could facilitate cell cycle re-entry in differentiating cells and support E1-dependent replication. Despite the well-established differences in the viral pathogenesis and cancer risk, it appears that low- and high-risk HPV types use fundamentally similar molecular strategies to maintain their genomes, albeit with important differences in their regulatory control. Our results provide new insights into the regulation of high and low-risk HPV genome replication and persistence in the epithelial basal and parabasal cells layers. Understanding the minimum requirement for viral genome persistence will facilitate the development of therapeutic strategies for clearance.
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Affiliation(s)
- Isao Murakami
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
- Department of Obstetrics and Gynecology, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan
| | - Nagayasu Egawa
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
| | - Heather Griffin
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
| | - Wen Yin
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
| | - Christian Kranjec
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
| | - Tomomi Nakahara
- Division of Carcinogenesis and Cancer Prevention, National Cancer Center Research Institute, Tokyo, Japan
| | - Tohru Kiyono
- Division of Carcinogenesis and Cancer Prevention, National Cancer Center Research Institute, Tokyo, Japan
| | - John Doorbar
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
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Gupta SM, Mania-Pramanik J. Molecular mechanisms in progression of HPV-associated cervical carcinogenesis. J Biomed Sci 2019; 26:28. [PMID: 31014351 PMCID: PMC6477741 DOI: 10.1186/s12929-019-0520-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 04/11/2019] [Indexed: 12/13/2022] Open
Abstract
Cervical cancer is the fourth most frequent cancer in women worldwide and a major cause of mortality in developing countries. Persistent infection with high-risk human papillomavirus (HPV) is a necessary cause for the development of cervical cancer. In addition, genetic and epigenetic alterations in host cell genes are crucial for progression of cervical precancerous lesions to invasive cancer. Although much progress has been made in understanding the life cycle of HPV and it’s role in the development of cervical cancer, there is still a critical need for accurate surveillance strategies and targeted therapeutic options to eradicate these cancers in patients. Given the widespread nature of HPV infection and the type specificity of currently available HPV vaccines, it is crucial that molecular details of the natural history of HPV infection as well as the biological activities of viral oncoproteins be elucidated. A better understanding of the mechanisms involved in oncogenesis can provide novel insights and opportunities for designing effective therapeutic approaches against HPV-associated malignancies. In this review, we briefly summarize epigenetic alterations and events that cause alterations in host genomes inducing cell cycle deregulation, aberrant proliferation and genomic instability contributing to tumorigenesis.
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Affiliation(s)
- Sadhana M Gupta
- Department of Infectious Diseases Biology, National Institute for Research in Reproductive Health, J.M. Street, Parel, Mumbai, 400012, India.
| | - Jayanti Mania-Pramanik
- Department of Infectious Diseases Biology, National Institute for Research in Reproductive Health, J.M. Street, Parel, Mumbai, 400012, India
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Das D, Bristol ML, Smith NW, James CD, Wang X, Pichierri P, Morgan IM. Werner Helicase Control of Human Papillomavirus 16 E1-E2 DNA Replication Is Regulated by SIRT1 Deacetylation. mBio 2019; 10:e00263-19. [PMID: 30890607 PMCID: PMC6426601 DOI: 10.1128/mbio.00263-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 02/04/2019] [Indexed: 01/03/2023] Open
Abstract
Human papillomaviruses (HPV) are double-stranded DNA viruses causative in a host of human diseases, including several cancers. Following infection, two viral proteins, E1 and E2, activate viral replication in association with cellular factors and stimulate the DNA damage response (DDR) during the replication process. E1-E2 uses homologous recombination (HR) to facilitate DNA replication, but an understanding of host factors involved in this process remains incomplete. Previously, we demonstrated that the class III deacetylase SIRT1, which can regulate HR, is recruited to E1-E2-replicating DNA and regulates the level of replication. Here, we demonstrate that SIRT1 promotes the fidelity of E1-E2 replication and that the absence of SIRT1 results in reduced recruitment of the DNA repair protein Werner helicase (WRN) to E1-E2-replicating DNA. CRISPR/Cas9 editing demonstrates that WRN, like SIRT1, regulates the quantity and fidelity of E1-E2 replication. This is the first report of WRN regulation of E1-E2 DNA replication, or a role for WRN in the HPV life cycle. In the absence of SIRT1 there is an increased acetylation and stability of WRN, but a reduced ability to interact with E1-E2-replicating DNA. We present a model in which E1-E2 replication turns on the DDR, stimulating SIRT1 deacetylation of WRN. This deacetylation promotes WRN interaction with E1-E2-replicating DNA to control the quantity and fidelity of replication. As well as offering a crucial insight into HPV replication control, this system offers a unique model for investigating the link between SIRT1 and WRN in controlling replication in mammalian cells.IMPORTANCE HPV16 is the major viral human carcinogen responsible for between 3 and 4% of all cancers worldwide. Following infection, this virus activates the DNA damage response (DDR) to promote its life cycle and recruits DDR proteins to its replicating DNA in order to facilitate homologous recombination during replication. This promotes the production of viable viral progeny. Our understanding of how HPV16 replication interacts with the DDR remains incomplete. Here, we demonstrate that the cellular deacetylase SIRT1, which is a part of the E1-E2 replication complex, regulates recruitment of the DNA repair protein WRN to the replicating DNA. We demonstrate that WRN regulates the level and fidelity of E1-E2 replication. Overall, the results suggest a mechanism by which SIRT1 deacetylation of WRN promotes its interaction with E1-E2-replicating DNA to control the levels and fidelity of that replication.
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Affiliation(s)
- Dipon Das
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Molly L Bristol
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Nathan W Smith
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Claire D James
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Xu Wang
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Pietro Pichierri
- Department of Environment and Health, Istituto Superiore di Sanità, Rome, Italy
| | - Iain M Morgan
- Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
- VCU Massey Cancer Center, Richmond, Virginia, USA
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Krump NA, Liu W, You J. Mechanisms of persistence by small DNA tumor viruses. Curr Opin Virol 2018; 32:71-79. [PMID: 30278284 DOI: 10.1016/j.coviro.2018.09.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/07/2018] [Accepted: 09/14/2018] [Indexed: 12/13/2022]
Abstract
Virus infection contributes to nearly 15% of human cancers worldwide. Many of the oncogenic viruses tend to cause cancer in immunosuppressed individuals, but maintain asymptomatic, persistent infection for decades in the general population. In this review, we discuss the tactics employed by two small DNA tumor viruses, Human papillomavirus (HPV) and Merkel cell polyomavirus (MCPyV), to establish persistent infection. We will also highlight recent key findings as well as outstanding questions regarding the mechanisms by which HPV and MCPyV evade host immune control to promote their survival. Since persistent infection enables virus-induced tumorigenesis, identifying the mechanisms by which small DNA tumor viruses achieve latent infection may inform new approaches for preventing and treating their respective human cancers.
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Affiliation(s)
- Nathan A Krump
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Wei Liu
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jianxin You
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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40
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Abstract
Viral DNA genomes have limited coding capacity and therefore harness cellular factors to facilitate replication of their genomes and generate progeny virions. Studies of viruses and how they interact with cellular processes have historically provided seminal insights into basic biology and disease mechanisms. The replicative life cycles of many DNA viruses have been shown to engage components of the host DNA damage and repair machinery. Viruses have evolved numerous strategies to navigate the cellular DNA damage response. By hijacking and manipulating cellular replication and repair processes, DNA viruses can selectively harness or abrogate distinct components of the cellular machinery to complete their life cycles. Here, we highlight consequences for viral replication and host genome integrity during the dynamic interactions between virus and host.
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Affiliation(s)
- Matthew D Weitzman
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
- Division of Protective Immunity and Division of Cancer Pathobiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104;
| | - Amélie Fradet-Turcotte
- Department of Molecular Biology, Medical Biochemistry, and Pathology, Faculty of Medicine, Université Laval, Québec G1V 0A6, Canada;
- CHU de Québec Research Center-Université Laval (L'Hôtel-Dieu de Québec), Cancer Research Center, Québec G1R 2J6, Canada
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41
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Abstract
Viral DNA genomes have limited coding capacity and therefore harness cellular factors to facilitate replication of their genomes and generate progeny virions. Studies of viruses and how they interact with cellular processes have historically provided seminal insights into basic biology and disease mechanisms. The replicative life cycles of many DNA viruses have been shown to engage components of the host DNA damage and repair machinery. Viruses have evolved numerous strategies to navigate the cellular DNA damage response. By hijacking and manipulating cellular replication and repair processes, DNA viruses can selectively harness or abrogate distinct components of the cellular machinery to complete their life cycles. Here, we highlight consequences for viral replication and host genome integrity during the dynamic interactions between virus and host.
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Affiliation(s)
- Matthew D Weitzman
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104.,Division of Protective Immunity and Division of Cancer Pathobiology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104;
| | - Amélie Fradet-Turcotte
- Department of Molecular Biology, Medical Biochemistry, and Pathology, Faculty of Medicine, Université Laval, Québec G1V 0A6, Canada; .,CHU de Québec Research Center-Université Laval (L'Hôtel-Dieu de Québec), Cancer Research Center, Québec G1R 2J6, Canada
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42
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Nilsson K, Wu C, Schwartz S. Role of the DNA Damage Response in Human Papillomavirus RNA Splicing and Polyadenylation. Int J Mol Sci 2018; 19:E1735. [PMID: 29895741 PMCID: PMC6032147 DOI: 10.3390/ijms19061735] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 05/29/2018] [Accepted: 06/08/2018] [Indexed: 12/16/2022] Open
Abstract
Human papillomaviruses (HPVs) have evolved to use the DNA repair machinery to replicate its DNA genome in differentiated cells. HPV activates the DNA damage response (DDR) in infected cells. Cellular DDR factors are recruited to the HPV DNA genome and position the cellular DNA polymerase on the HPV DNA and progeny genomes are synthesized. Following HPV DNA replication, HPV late gene expression is activated. Recent research has shown that the DDR factors also interact with RNA binding proteins and affects RNA processing. DDR factors activated by DNA damage and that associate with HPV DNA can recruit splicing factors and RNA binding proteins to the HPV DNA and induce HPV late gene expression. This induction is the result of altered alternative polyadenylation and splicing of HPV messenger RNA (mRNA). HPV uses the DDR machinery to replicate its DNA genome and to activate HPV late gene expression at the level of RNA processing.
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Affiliation(s)
- Kersti Nilsson
- Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden.
| | - Chengjun Wu
- Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden.
| | - Stefan Schwartz
- Department of Laboratory Medicine, Lund University, 221 84 Lund, Sweden.
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43
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Nilsson K, Wu C, Kajitani N, Yu H, Tsimtsirakis E, Gong L, Winquist EB, Glahder J, Ekblad L, Wennerberg J, Schwartz S. The DNA damage response activates HPV16 late gene expression at the level of RNA processing. Nucleic Acids Res 2018; 46:5029-5049. [PMID: 29596642 PMCID: PMC6007495 DOI: 10.1093/nar/gky227] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 03/15/2018] [Accepted: 03/19/2018] [Indexed: 12/13/2022] Open
Abstract
We show that the alkylating cancer drug melphalan activated the DNA damage response and induced human papillomavirus type 16 (HPV16) late gene expression in an ATM- and Chk1/2-dependent manner. Activation of HPV16 late gene expression included inhibition of the HPV16 early polyadenylation signal that resulted in read-through into the late region of HPV16. This was followed by activation of the exclusively late, HPV16 splice sites SD3632 and SA5639 and production of spliced late L1 mRNAs. Altered HPV16 mRNA processing was paralleled by increased association of phosphorylated BRCA1, BARD1, BCLAF1 and TRAP150 with HPV16 DNA, and increased association of RNA processing factors U2AF65 and hnRNP C with HPV16 mRNAs. These RNA processing factors inhibited HPV16 early polyadenylation and enhanced HPV16 late mRNA splicing, thereby activating HPV16 late gene expression.
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Affiliation(s)
- Kersti Nilsson
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
| | - Chengjun Wu
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
| | - Naoko Kajitani
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
| | - Haoran Yu
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
| | | | - Lijing Gong
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
- China Academy of Sport and Health Sciences, Beijing Sport University, Xinxi Road 48, Haidian District, 100084 Beijing, China
| | - Ellenor B Winquist
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
| | - Jacob Glahder
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
| | - Lars Ekblad
- Department of Clinical Sciences Lund, Oncology and Pathology, Lund University, Skane University Hospital, 221 85 Lund, Sweden
| | - Johan Wennerberg
- Department of Clinical Sciences Lund, Oto-rhino-laryngology, Head and Neck Surgery, Lund University, Skane University Hospital, 221 85 Lund, Sweden
| | - Stefan Schwartz
- Department of Laboratory Medicine, Lund University, BMC-B13, 221 84 Lund, Sweden
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Pancholi NJ, Price AM, Weitzman MD. Take your PIKK: tumour viruses and DNA damage response pathways. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0269. [PMID: 28893936 DOI: 10.1098/rstb.2016.0269] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/12/2017] [Indexed: 12/13/2022] Open
Abstract
Viruses regulate cellular processes to facilitate viral replication. Manipulation of nuclear proteins and pathways by nuclear replicating viruses often causes cellular genome instability that contributes to transformation. The cellular DNA damage response (DDR) safeguards the host to maintain genome integrity, but DNA tumour viruses can manipulate the DDR to promote viral propagation. In this review, we describe the interactions of DNA tumour viruses with the phosphatidylinositol 3-kinase-like protein kinase (PIKK) pathways, which are central regulatory arms of the DDR. We review how signalling through the ataxia telangiectasia mutated (ATM), ataxia telangiectasia and Rad3 related (ATR), and DNA-dependent protein kinases (DNA-PK) influences viral life cycles, and how their manipulation by viral proteins may contribute to tumour formation.This article is part of the themed issue 'Human oncogenic viruses'.
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Affiliation(s)
- Neha J Pancholi
- Division of Cancer Pathobiology and Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.,Cell and Molecular Biology Graduate Program, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Alexander M Price
- Division of Cancer Pathobiology and Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Matthew D Weitzman
- Division of Cancer Pathobiology and Division of Protective Immunity, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA .,Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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45
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Edwards TG, Fisher C. Antiviral activity of pyrrole-imidazole polyamides against SV40 and BK polyomaviruses. Antiviral Res 2018; 152:68-75. [DOI: 10.1016/j.antiviral.2018.02.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 02/11/2018] [Accepted: 02/13/2018] [Indexed: 02/07/2023]
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46
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Baedyananda F, Chaiwongkot A, Bhattarakosol P. Elevated HPV16 E1 Expression Is Associated with Cervical Cancer Progression. Intervirology 2018; 60:171-180. [PMID: 29495005 DOI: 10.1159/000487048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 01/22/2018] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVES The primary replication protein, HPV E1, has been shown to play a role in mitigating host defence and disrupting normal cell cycle processes, leading to the development of cancer. This study investigated the expression profile of HPV16 E1 in various stages of cervical cancer development and the factors that control E1 expression. METHODS One hundred and twenty-four HPV16-positive cervical samples ranging from normal to CIN 1, CIN 2/3, and SCC lesions were studied. E1 mRNA expression was determined by ddPCR. Methylation of promoters p97 and p670 was quantified by pyrosequencing, while PCR, qPCR, and sequencing were used to determine the physical state and variations of the HPV16 E1 genome. RESULTS Increased E1 mRNA expression related to disease progression (normal 0.18, CIN 1 0.41, CIN 2/3 0.65, and SCC 0.79) was demonstrated with a significant positive correlation (r = 0.661, p = 0.019). No association between physical state and E1 expression was found. Methylation of p97 and p670 promoters showed significant elevation in SCC compared to normal samples. Only 4.2% showed genomic variations of HPV16 E1 63-bp duplication. CONCLUSION E1 may play a role in cancer development. The detection of E1 mRNA and promoter methylation may be useful as cancer prognostic markers.
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Affiliation(s)
- Fern Baedyananda
- Joint PhD Program in Biomedical Sciences and Biotechnology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Arkom Chaiwongkot
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Parvapan Bhattarakosol
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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47
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Warburton A, Redmond CJ, Dooley KE, Fu H, Gillison ML, Akagi K, Symer DE, Aladjem MI, McBride AA. HPV integration hijacks and multimerizes a cellular enhancer to generate a viral-cellular super-enhancer that drives high viral oncogene expression. PLoS Genet 2018; 14:e1007179. [PMID: 29364907 PMCID: PMC5798845 DOI: 10.1371/journal.pgen.1007179] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 02/05/2018] [Accepted: 01/01/2018] [Indexed: 12/12/2022] Open
Abstract
Integration of human papillomavirus (HPV) genomes into cellular chromatin is common in HPV-associated cancers. Integration is random, and each site is unique depending on how and where the virus integrates. We recently showed that tandemly integrated HPV16 could result in the formation of a super-enhancer-like element that drives transcription of the viral oncogenes. Here, we characterize the chromatin landscape and genomic architecture of this integration locus to elucidate the mechanisms that promoted de novo super-enhancer formation. Using next-generation sequencing and molecular combing/fiber-FISH, we show that ~26 copies of HPV16 are integrated into an intergenic region of chromosome 2p23.2, interspersed with 25 kb of amplified, flanking cellular DNA. This interspersed, co-amplified viral-host pattern is frequent in HPV-associated cancers and here we designate it as Type III integration. An abundant viral-cellular fusion transcript encoding the viral E6/E7 oncogenes is expressed from the integration locus and the chromatin encompassing both the viral enhancer and a region in the adjacent amplified cellular sequences is strongly enriched in the super-enhancer markers H3K27ac and Brd4. Notably, the peak in the amplified cellular sequence corresponds to an epithelial-cell-type specific enhancer. Thus, HPV16 integration generated a super-enhancer-like element composed of tandem interspersed copies of the viral upstream regulatory region and a cellular enhancer, to drive high levels of oncogene expression.
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Affiliation(s)
- Alix Warburton
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Catherine J. Redmond
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Katharine E. Dooley
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Haiqing Fu
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Maura L. Gillison
- Department of Internal Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Keiko Akagi
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, United States of America
| | - David E. Symer
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, United States of America
- Human Cancer Genetics Program, Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, United States of America
- Department of Biomedical Informatics (adjunct), The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, United States of America
| | - Mirit I. Aladjem
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Alison A. McBride
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
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Why Human Papillomaviruses Activate the DNA Damage Response (DDR) and How Cellular and Viral Replication Persists in the Presence of DDR Signaling. Viruses 2017; 9:v9100268. [PMID: 28934154 PMCID: PMC5691620 DOI: 10.3390/v9100268] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 09/12/2017] [Accepted: 09/15/2017] [Indexed: 12/15/2022] Open
Abstract
Human papillomaviruses (HPV) require the activation of the DNA damage response (DDR) in order to undergo a successful life cycle. This activation presents a challenge for the virus and the infected cell: how does viral and host replication proceed in the presence of a DDR that ordinarily arrests replication; and how do HPV16 infected cells retain the ability to proliferate in the presence of a DDR that ordinarily arrests the cell cycle? This raises a further question: why do HPV activate the DDR? The answers to these questions are only partially understood; a full understanding could identify novel therapeutic strategies to target HPV cancers. Here, we propose that the rapid replication of an 8 kb double stranded circular genome during infection creates aberrant DNA structures that attract and activate DDR proteins. Therefore, HPV replication in the presence of an active DDR is a necessity for a successful viral life cycle in order to resolve these DNA structures on viral genomes; without an active DDR, successful replication of the viral genome would not proceed. We discuss the essential role of TopBP1 in this process and also how viral and cellular replication proceeds in HPV infected cells in the presence of DDR signals.
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49
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Moody C. Mechanisms by which HPV Induces a Replication Competent Environment in Differentiating Keratinocytes. Viruses 2017; 9:v9090261. [PMID: 28925973 PMCID: PMC5618027 DOI: 10.3390/v9090261] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 09/14/2017] [Accepted: 09/15/2017] [Indexed: 12/15/2022] Open
Abstract
Human papillomaviruses (HPV) are the causative agents of cervical cancer and are also associated with other genital malignancies, as well as an increasing number of head and neck cancers. HPVs have evolved their life cycle to contend with the different cell states found in the stratified epithelium. Initial infection and viral genome maintenance occurs in the proliferating basal cells of the stratified epithelium, where cellular replication machinery is abundant. However, the productive phase of the viral life cycle, including productive replication, late gene expression and virion production, occurs upon epithelial differentiation, in cells that normally exit the cell cycle. This review outlines how HPV interfaces with specific cellular signaling pathways and factors to provide a replication-competent environment in differentiating cells.
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Affiliation(s)
- Cary Moody
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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50
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The human papillomavirus replication cycle, and its links to cancer progression: a comprehensive review. Clin Sci (Lond) 2017; 131:2201-2221. [DOI: 10.1042/cs20160786] [Citation(s) in RCA: 156] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/26/2017] [Accepted: 07/03/2017] [Indexed: 12/21/2022]
Abstract
HPVs (human papillomaviruses) infect epithelial cells and their replication cycle is intimately linked to epithelial differentiation. There are over 200 different HPV genotypes identified to date and each displays a strict tissue specificity for infection. HPV infection can result in a range of benign lesions, for example verrucas on the feet, common warts on the hands, or genital warts. HPV infects dividing basal epithelial cells where its dsDNA episomal genome enters the nuclei. Upon basal cell division, an infected daughter cell begins the process of keratinocyte differentiation that triggers a tightly orchestrated pattern of viral gene expression to accomplish a productive infection. A subset of mucosal-infective HPVs, the so-called ‘high risk’ (HR) HPVs, cause cervical disease, categorized as low or high grade. Most individuals will experience transient HR-HPV infection during their lifetime but these infections will not progress to clinically significant cervical disease or cancer because the immune system eventually recognizes and clears the virus. Cancer progression is due to persistent infection with an HR-HPV. HR-HPV infection is the cause of >99.7% cervical cancers in women, and a subset of oropharyngeal cancers, predominantly in men. HPV16 (HR-HPV genotype 16) is the most prevalent worldwide and the major cause of HPV-associated cancers. At the molecular level, cancer progression is due to increased expression of the viral oncoproteins E6 and E7, which activate the cell cycle, inhibit apoptosis, and allow accumulation of DNA damage. This review aims to describe the productive life cycle of HPV and discuss the roles of the viral proteins in HPV replication. Routes to viral persistence and cancer progression are also discussed.
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