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  1. Article ; Online: Impact of the COVID-19 pandemic on otolaryngology resident rhinology education.

    Murthy, Akshay K / Fontan, Christian T / Filippa Trikantzopoulou, Maria / Fitzpatrick, Thomas H / Levy, Joshua M / Alt, Jeremiah A / Schuman, Theodore A

    International forum of allergy & rhinology

    2022  Volume 12, Issue 8, Page(s) 1067–1070

    MeSH term(s) COVID-19/epidemiology ; Education, Medical, Graduate ; Humans ; Internship and Residency ; Otolaryngology/education ; Pandemics ; SARS-CoV-2
    Language English
    Publishing date 2022-01-10
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2625826-2
    ISSN 2042-6984 ; 2042-6976
    ISSN (online) 2042-6984
    ISSN 2042-6976
    DOI 10.1002/alr.22956
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Human papillomavirus 16 E2 blocks cellular senescence in response to activation of the DNA damage response.

    Fontan, Christian T / Prabhakar, Apurva T / Wang, Xu / Karimi, Elmira / Bristol, Molly L / James, Claire D / Morgan, Iain M

    Virology

    2022  Volume 575, Page(s) 54–62

    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. ... ...

    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.
    MeSH term(s) Cellular Senescence ; Cisplatin/pharmacology ; DNA Damage ; DNA-Binding Proteins/metabolism ; Host-Pathogen Interactions ; Human papillomavirus 16/metabolism ; Humans ; Oncogene Proteins, Viral/genetics ; Oncogene Proteins, Viral/metabolism ; Virus Replication
    Chemical Substances DNA-Binding Proteins ; Oncogene Proteins, Viral ; Cisplatin (Q20Q21Q62J)
    Language English
    Publishing date 2022-08-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 200425-2
    ISSN 1096-0341 ; 0042-6822
    ISSN (online) 1096-0341
    ISSN 0042-6822
    DOI 10.1016/j.virol.2022.08.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Interaction with TopBP1 Is Required for Human Papillomavirus 16 E2 Plasmid Segregation/Retention Function during Mitosis.

    Prabhakar, Apurva T / James, Claire D / Das, Dipon / Fontan, Christian T / Otoa, Raymonde / Wang, Xu / Bristol, Molly L / Morgan, Iain M

    Journal of virology

    2022  Volume 96, Issue 16, Page(s) e0083022

    Abstract: Human papillomavirus 16 (HPV16) E2 is a DNA-binding protein that regulates transcription, replication and potentially, segregation of the HPV16 genome during the viral life cycle. In the segregation model, E2 simultaneously binds to viral and host ... ...

    Abstract Human papillomavirus 16 (HPV16) E2 is a DNA-binding protein that regulates transcription, replication and potentially, segregation of the HPV16 genome during the viral life cycle. In the segregation model, E2 simultaneously binds to viral and host chromatin, acting as a bridge to ensure that viral genomes reside in daughter nuclei following cell division. The host chromatin receptor for E2 mediating this function is unknown. Recently, we demonstrated that CK2 phosphorylation of E2 on serine 23 (S23) is required for interaction with TopBP1, and that this interaction promotes E2 and TopBP1 recruitment to mitotic chromatin. Here, we demonstrate that in U2OS cells expressing wild-type E2 and a non-TopBP1-binding mutant (S23A, serine 23 mutated to alanine), interaction with TopBP1 is essential for E2 recruitment of plasmids to mitotic chromatin. Using novel quantitative segregation assays, we demonstrate that interaction with TopBP1 is required for E2 plasmid segregation function in U2OS and N/Tert-1 cells. Small interfering RNA (siRNA) knockdown of TopBP1 or CK2 enzyme components disrupts E2 segregation/retention function. The interaction of E2 with TopBP1 promotes increased levels of E2 protein during mitosis in U2OS and N/Tert-1 cells, as well as in human foreskin keratinocytes (HFK) immortalized by the HPV16 genome. Overall, our results demonstrate that E2 has plasmid segregation activity, and that the E2-TopBP1 interaction is essential for this E2 function.
    MeSH term(s) Carrier Proteins/genetics ; Carrier Proteins/metabolism ; Chromatin/metabolism ; DNA-Binding Proteins/genetics ; DNA-Binding Proteins/metabolism ; Genome, Viral ; Human papillomavirus 16/physiology ; Humans ; Mitosis ; Nuclear Proteins/metabolism ; Oncogene Proteins, Viral/metabolism ; Papillomavirus Infections/metabolism ; Papillomavirus Infections/pathology ; Papillomavirus Infections/virology ; Plasmids/genetics
    Chemical Substances Carrier Proteins ; Chromatin ; DNA-Binding Proteins ; E2 protein, Human papillomavirus type 16 ; Nuclear Proteins ; Oncogene Proteins, Viral ; TOPBP1 protein, human
    Language English
    Publishing date 2022-07-26
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.00830-22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Human papillomavirus 16 E2 blocks cellular senescence in response to activation of the DNA damage response

    Fontan, Christian T. / Prabhakar, Apurva T. / Wang, Xu / Karimi, Elmira / Bristol, Molly L. / James, Claire D. / Morgan, Iain M.

    Virology. 2022 Oct., v. 575

    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. ... ...

    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.
    Keywords DNA damage ; Human papillomavirus type 16 ; apoptosis ; cell proliferation ; cell senescence ; cisplatin ; viral genome ; virology
    Language English
    Dates of publication 2022-10
    Size p. 54-62.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 200425-2
    ISSN 1096-0341 ; 0042-6822
    ISSN (online) 1096-0341
    ISSN 0042-6822
    DOI 10.1016/j.virol.2022.08.007
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Estrogen Attenuates the Growth of Human Papillomavirus-Positive Epithelial Cells.

    Bristol, Molly L / James, Claire D / Wang, Xu / Fontan, Christian T / Morgan, Iain M

    mSphere

    2020  Volume 5, Issue 2

    Abstract: Human papillomaviruses (HPVs) are small, double-stranded DNA viruses that are significant risk factors in the development of cancer, and HPV accounts for approximately 5% of all worldwide cancers. Recent studies using data from The Cancer Genome Atlas ( ... ...

    Abstract Human papillomaviruses (HPVs) are small, double-stranded DNA viruses that are significant risk factors in the development of cancer, and HPV accounts for approximately 5% of all worldwide cancers. Recent studies using data from The Cancer Genome Atlas (TCGA) have demonstrated that elevated levels of estrogen receptor alpha (ERα) are associated with improved survival in oropharyngeal cancers, and these elevated receptor levels were linked with human papillomavirus-positive cancers (HPV+cancers). There has been a dramatic increase in HPV-related head and neck squamous cell carcinomas (HPV+HNSCCs) over the last 2 decades, and therapeutic options for this ongoing health crisis are a priority; currently, there are no antiviral therapeutics available for combatting HPV+cancers. During our TGCA studies on head and neck cancer, we had also discovered the overexpression of ERα in HPV+cancers. Here, we demonstrate that 17β-estradiol (estrogen) attenuates the growth/cell viability of HPV+cancers
    MeSH term(s) Cell Line, Tumor ; Cell Proliferation/drug effects ; Epithelial Cells/drug effects ; Epithelial Cells/virology ; Estrogen Receptor alpha/genetics ; Estrogens/pharmacology ; Head and Neck Neoplasms/drug therapy ; Head and Neck Neoplasms/virology ; Human papillomavirus 16/drug effects ; Human papillomavirus 16/genetics ; Humans ; Oncogene Proteins, Viral/genetics ; Papillomavirus E7 Proteins/genetics ; Papillomavirus Infections/complications ; Papillomavirus Infections/drug therapy ; Repressor Proteins/genetics ; Squamous Cell Carcinoma of Head and Neck/drug therapy ; Squamous Cell Carcinoma of Head and Neck/virology
    Chemical Substances E6 protein, Human papillomavirus type 16 ; Estrogen Receptor alpha ; Estrogens ; Oncogene Proteins, Viral ; Papillomavirus E7 Proteins ; Repressor Proteins ; oncogene protein E7, Human papillomavirus type 16
    Language English
    Publishing date 2020-03-18
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ISSN 2379-5042
    ISSN (online) 2379-5042
    DOI 10.1128/mSphere.00049-20
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Human papillomavirus 16 E2 interaction with TopBP1 is required for E2 and viral genome stability during the viral life cycle.

    Prabhakar, Apurva T / James, Claire D / Fontan, Christian T / Otoa, Raymonde / Wang, Xu / Bristol, Molly L / Hill, Ronald D / Dubey, Aanchal / Morgan, Iain M

    bioRxiv : the preprint server for biology

    2023  

    Abstract: CK2 phosphorylation of HPV16 E2 at serine 23 promotes interaction with TopBP1, and this interaction is important for E2 plasmid segregation function. Here we demonstrate that the E2-TopBP1 interaction is critical for E2 and viral genome stability during ... ...

    Abstract CK2 phosphorylation of HPV16 E2 at serine 23 promotes interaction with TopBP1, and this interaction is important for E2 plasmid segregation function. Here we demonstrate that the E2-TopBP1 interaction is critical for E2 and viral genome stability during the viral life cycle. Introduction of the S23A mutation into the HPV16 genome results in a loss of E2 expression and viral genome integration during organotypic rafting. Co-culture of N/Tert-1+E2-S23A cells with J2 fibroblasts results in E2-S23A degradation via the proteasome, wild-type E2 is not degraded. TopBP1 siRNA treatment of N/Tert-1+E2-WT cells results in E2 degradation only in the presence of J2 cells demonstrating the critical role for TopBP1 in maintaining E2 stability. The CK2 inhibitor CX4945 promotes E2-WT degradation in the presence of fibroblasts as it disrupts E2-TopBP1 interaction. siRNA targeting SIRT1 rescues E2-S23A stability in N/Tert-1 cells treated with J2 fibroblasts, with an increased E2-S23A acetylation. The results demonstrate that the E2-TopBP1 interaction is critical during the viral life cycle as it prevents fibroblast stimulated SIRT1 mediated deacetylation of E2 that promotes protein degradation. This means that the E2-TopBP1 complex maintains E2 and viral genome stability and that disruption of this complex can promote viral genome integration. Finally, we demonstrate that HPV11 E2 also interacts with TopBP1 and that this interaction is critical for HPV11 E2 stability in the presence of J2 cells. Treatment of N/Tert-1+11E2-WT cells with CX4945 results in 11E2 degradation. Therefore, CK2 inhibition is a therapeutic strategy for alleviating HPV11 diseases, including juvenile respiratory papillomatosis.
    Importance: Human papillomaviruses are pathogens that cause a host of diseases ranging from benign warts to cancers. There are no therapeutics available for combating these diseases that directly target viral proteins or processes, therefore we must enhance our understanding of HPV life cycles to assist with identifying novel treatments. In this report, we demonstrate that HPV16 and HPV11 E2 protein expression is dependent upon TopBP1 interaction in keratinocytes interacting with fibroblasts, which recapitulate stromal interactions in culture. The degradation of 16E2 promotes HPV16 genome integration, therefore the E2-TopBP1 interaction is critical during the viral life cycle. We demonstrate that the CK2 inhibitor CX4945 disrupts HPV11 interaction with TopBP1 and destabilizes HPV11 E2 protein in the presence of J2 fibroblasts; we propose that CX4945 could alleviate HPV11 disease burden.
    Language English
    Publishing date 2023-01-13
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.01.11.523702
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Direct interaction with the BRD4 carboxyl-terminal motif (CTM) and TopBP1 is required for human papillomavirus 16 E2 association with mitotic chromatin and plasmid segregation function.

    Prabhakar, Apurva T / James, Claire D / Fontan, Christian T / Otoa, Raymonde / Wang, Xu / Bristol, Molly L / Hill, Ronald D / Dubey, Aanchal / Wu, Shwu-Yuan / Chiang, Cheng-Ming / Morgan, Iain M

    bioRxiv : the preprint server for biology

    2023  

    Abstract: During the human papillomavirus 16 life cycle, the E2 protein binds simultaneously to the viral genome and host chromatin throughout mitosis, ensuring viral genomes reside in daughter cell nuclei following cell division. Previously, we demonstrated that ... ...

    Abstract During the human papillomavirus 16 life cycle, the E2 protein binds simultaneously to the viral genome and host chromatin throughout mitosis, ensuring viral genomes reside in daughter cell nuclei following cell division. Previously, we demonstrated that CK2 phosphorylation of E2 on serine 23 promotes interaction with TopBP1, and that this interaction is required for optimum E2 mitotic chromatin association and plasmid segregation function. Others have implicated BRD4 in mediating the plasmid segregation function of E2 and we have demonstrated that there is a TopBP1-BRD4 complex in the cell. We therefore further investigated the role of the E2-BRD4 interaction in mediating E2 association with mitotic chromatin and plasmid segregation function. Using a combination of immunofluorescence and our novel plasmid segregation assay in U2OS and N/Tert-1 cells stably expressing a variety of E2 mutants, we report that direct interaction with the BRD4 carboxyl-terminal motif (CTM) and TopBP1 is required for E2 association with mitotic chromatin and plasmid segregation. We also identify a novel TopBP1 mediated interaction between E2 and the BRD4 extra-terminal (ET) domain
    Importance: HPV16 is a causative agent in around 3-4% of all human cancers and currently there are no anti-viral therapeutics available for combating this disease burden. In order to identify new therapeutic targets, we must increase our understanding of the HPV16 life cycle. Previously, we demonstrated that an interaction between E2 and the cellular protein TopBP1 mediates the plasmid segregation function of E2, allowing distribution of viral genomes into daughter nuclei following cell division. Here, we demonstrate that E2 interaction with an additional host protein, BRD4, is also essential for E2 segregation function, and that BRD4 exists in a complex with TopBP1. Overall, these results enhance our understanding of a critical part of the HPV16 life cycle and presents several therapeutic targets for disruption of the viral life cycle.
    Language English
    Publishing date 2023-05-26
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.05.25.542291
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Human Papillomavirus 16 E2 Interaction with TopBP1 Is Required for E2 and Viral Genome Stability during the Viral Life Cycle.

    Prabhakar, Apurva T / James, Claire D / Fontan, Christian T / Otoa, Raymonde / Wang, Xu / Bristol, Molly L / Hill, Ronald D / Dubey, Aanchal / Morgan, Iain M

    Journal of virology

    2023  Volume 97, Issue 3, Page(s) e0006323

    Abstract: CK2 phosphorylation of HPV16 E2 at serine 23 promotes interaction with TopBP1, and this interaction is important for E2 plasmid segregation function. Here, we demonstrate that the E2-TopBP1 interaction is critical for E2 and viral genome stability during ...

    Abstract CK2 phosphorylation of HPV16 E2 at serine 23 promotes interaction with TopBP1, and this interaction is important for E2 plasmid segregation function. Here, we demonstrate that the E2-TopBP1 interaction is critical for E2 and viral genome stability during the viral life cycle. Introduction of the S23A mutation into the HPV16 genome results in a loss of E2 expression and viral genome integration during organotypic rafting. Coculture of N/Tert-1+E2-S23A cells with J2 fibroblasts results in E2-S23A degradation via the proteasome; wild-type E2 is not degraded. TopBP1 siRNA treatment of N/Tert-1+E2-WT cells results in E2 degradation only in the presence of J2 cells demonstrating the critical role for TopBP1 in maintaining E2 stability. The CK2 inhibitor CX4945 promotes E2-WT degradation in the presence of fibroblasts as it disrupts E2-TopBP1 interaction. siRNA targeting SIRT1 rescues E2-S23A stability in N/Tert-1 cells treated with J2 fibroblasts, with an increased E2-S23A acetylation. The results demonstrate that the E2-TopBP1 interaction is critical during the viral life cycle as it prevents fibroblast stimulated SIRT1 mediated deacetylation of E2 that promotes protein degradation. This means that the E2-TopBP1 complex maintains E2 and viral genome stability and that disruption of this complex can promote viral genome integration. Finally, we demonstrate that HPV11 E2 also interacts with TopBP1 and that this interaction is critical for HPV11 E2 stability in the presence of J2 cells. Treatment of N/Tert-1 + 11E2-WT cells with CX4945 results in 11E2 degradation. Therefore, CK2 inhibition is a therapeutic strategy for alleviating HPV11 diseases, including juvenile respiratory papillomatosis.
    MeSH term(s) Humans ; Carrier Proteins/metabolism ; DNA-Binding Proteins/genetics ; DNA-Binding Proteins/metabolism ; Genome, Viral ; Genomic Instability ; Human papillomavirus 16/metabolism ; Human Papillomavirus Viruses ; Nuclear Proteins/metabolism ; Oncogene Proteins, Viral/genetics ; Oncogene Proteins, Viral/metabolism ; Sirtuin 1/metabolism
    Chemical Substances Carrier Proteins ; DNA-Binding Proteins ; Nuclear Proteins ; Oncogene Proteins, Viral ; Sirtuin 1 (EC 3.5.1.-) ; TOPBP1 protein, human ; E2 protein, Human papillomavirus type 16
    Language English
    Publishing date 2023-02-22
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.00063-23
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Direct interaction with the BRD4 carboxyl-terminal motif (CTM) and TopBP1 is required for human papillomavirus 16 E2 association with mitotic chromatin and plasmid segregation function.

    Prabhakar, Apurva T / James, Claire D / Fontan, Christian T / Otoa, Raymonde / Wang, Xu / Bristol, Molly L / Yeager, Calvin / Hill, Ronald D / Dubey, Aanchal / Wu, Shwu-Yuan / Chiang, Cheng-Ming / Morgan, Iain M

    Journal of virology

    2023  Volume 97, Issue 10, Page(s) e0078223

    Abstract: Importance: Human papillomavirus 16 (HPV16) is a causative agent in around 3%-4% of all human cancers, and currently, there are no anti-viral therapeutics available for combating this disease burden. In order to identify new therapeutic targets, we must ...

    Abstract Importance: Human papillomavirus 16 (HPV16) is a causative agent in around 3%-4% of all human cancers, and currently, there are no anti-viral therapeutics available for combating this disease burden. In order to identify new therapeutic targets, we must increase our understanding of the HPV16 life cycle. Previously, we demonstrated that an interaction between E2 and the cellular protein TopBP1 mediates the plasmid segregation function of E2, allowing distribution of viral genomes into daughter nuclei following cell division. Here, we demonstrate that E2 interaction with an additional host protein, BRD4, is also essential for E2 segregation function, and that BRD4 exists in a complex with TopBP1. Overall, these results enhance our understanding of a critical part of the HPV16 life cycle and presents several therapeutic targets for disruption of the viral life cycle.
    MeSH term(s) Humans ; Bromodomain Containing Proteins ; Cell Cycle Proteins/genetics ; Cell Cycle Proteins/metabolism ; Chromatin/metabolism ; DNA-Binding Proteins/genetics ; DNA-Binding Proteins/metabolism ; Human papillomavirus 16/genetics ; Human papillomavirus 16/metabolism ; Nuclear Proteins/genetics ; Nuclear Proteins/metabolism ; Oncogene Proteins, Viral/genetics ; Oncogene Proteins, Viral/metabolism ; Plasmids/genetics ; Transcription Factors/genetics ; Transcription Factors/metabolism
    Chemical Substances BRD4 protein, human ; Bromodomain Containing Proteins ; Cell Cycle Proteins ; Chromatin ; DNA-Binding Proteins ; Nuclear Proteins ; Oncogene Proteins, Viral ; Transcription Factors ; E2 protein, Human papillomavirus type 16 ; TOPBP1 protein, human
    Language English
    Publishing date 2023-09-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.00782-23
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: A Critical Role for p53 during the HPV16 Life Cycle.

    Fontan, Christian T / James, Claire D / Prabhakar, Apurva T / Bristol, Molly L / Otoa, Raymonde / Wang, Xu / Karimi, Elmira / Rajagopalan, Pavithra / Basu, Devraj / Morgan, Iain M

    Microbiology spectrum

    2022  Volume 10, Issue 3, Page(s) e0068122

    Abstract: Human papillomaviruses (HPV) are causative agents in ano-genital and oral cancers; HPV16 is the most prevalent type detected in human cancers. The HPV16 E6 protein targets p53 for proteasomal degradation to facilitate proliferation of the HPV16 infected ... ...

    Abstract Human papillomaviruses (HPV) are causative agents in ano-genital and oral cancers; HPV16 is the most prevalent type detected in human cancers. The HPV16 E6 protein targets p53 for proteasomal degradation to facilitate proliferation of the HPV16 infected cell. However, in HPV16 immortalized cells E6 is predominantly spliced (E6*) and unable to degrade p53. Here, we demonstrate that human foreskin keratinocytes immortalized by HPV16 (HFK+HPV16), and HPV16 positive oropharyngeal cancers, retain significant expression of p53. In addition, p53 levels increase in HPV16+ head and neck cancer cell lines following treatment with cisplatin. Introduction of full-length E6 into HFK+HPV16 resulted in attenuation of cellular growth (in hTERT immortalized HFK, E6 expression promoted enhanced proliferation). An understudied interaction is that between E2 and p53 and we investigated whether this was important for the viral life cycle. We generated mutant genomes with E2 unable to interact with p53 resulting in profound phenotypes in primary HFK. The mutant induced hyper-proliferation, but an ultimate arrest of cell growth; β-galactosidase staining demonstrated increased senescence, and COMET assays showed increased DNA damage compared with HFK+HPV16 wild-type cells. There was failure of the viral life cycle in organotypic rafts with the mutant HFK resulting in premature differentiation and reduced proliferation. The results demonstrate that p53 expression is critical during the HPV16 life cycle, and that this may be due to a functional interaction between E2 and p53. Disruption of this interaction has antiviral potential.
    MeSH term(s) Animals ; Human papillomavirus 16/genetics ; Human papillomavirus 16/metabolism ; Humans ; Life Cycle Stages ; Oncogene Proteins, Viral/genetics ; Oncogene Proteins, Viral/metabolism ; Papillomaviridae/genetics ; Papillomavirus Infections ; Tumor Suppressor Protein p53/genetics ; Tumor Suppressor Protein p53/metabolism
    Chemical Substances Oncogene Proteins, Viral ; Tumor Suppressor Protein p53
    Language English
    Publishing date 2022-05-24
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2807133-5
    ISSN 2165-0497 ; 2165-0497
    ISSN (online) 2165-0497
    ISSN 2165-0497
    DOI 10.1128/spectrum.00681-22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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