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Srisathaporn S, Pientong C, Heawchaiyaphum C, Nukpook T, Aromseree S, Ekalaksananan T. The Oncogenic Role of VWA8-AS1, a Long Non-Coding RNA, in Epstein-Barr Virus-Associated Oral Squamous Cell Carcinoma: An Integrative Transcriptome and Functional Analysis. Int J Mol Sci 2024; 25:12565. [PMID: 39684278 DOI: 10.3390/ijms252312565] [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: 10/24/2024] [Revised: 11/16/2024] [Accepted: 11/21/2024] [Indexed: 12/18/2024] Open
Abstract
Dysregulated long non-coding RNA (lncRNA) expression is linked to various cancers and may be influenced by oncogenic Epstein-Barr virus (EBV) infection, a known and detectable risk factor in oral squamous cell carcinoma (OSCC) patients. However, research on the oncogenic role of EBV-induced lncRNAs in OSCC is limited. To identify lncRNA-associated EBV infection and OSCC carcinogenesis, the differential expression of RNA-seq datasets from paired normal adjacent and OSCC tissues, and microarray data from EBV-negative and EBV-positive SCC25 cells, were identified and selected, respectively, for interaction, functional analysis, and CCK-8 cell proliferation, wound healing, and invasion Transwell assays. In OSCC tissues, 6731 differentially expressed lncRNAs were identified when compared to normal tissues from RNA-seq datasets, with 295 linked to EBV-induced OSCC carcinogenesis from microarray datasets. The EBV-induced lncRNA VWA8-AS1 showed significant upregulation in EBV-positive SCC25 cells and EBV-infected adjacent and OSCC tissue samples. VWA8-AS1 potentially promotes OSCC via the lncRNA-miRNA-mRNA axis or direct protein interactions, affecting various cellular processes. Studies in OSCC cell lines revealed that elevated VWA8-AS1 levels enhanced cell migration and invasion. This study demonstrates VWA8-AS1's contribution to tumor progression and possible interactions with its targets in OSCC, offering insights for future research on functional mechanisms and therapeutic targets in EBV-associated OSCC.
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Affiliation(s)
- Sawarot Srisathaporn
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Chamsai Pientong
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Chukkris Heawchaiyaphum
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Thawaree Nukpook
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sirinart Aromseree
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Tipaya Ekalaksananan
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen 40002, Thailand
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2
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Singh DR, Nelson SE, Pawelski AS, Kansra AS, Fogarty SA, Bristol JA, Ohashi M, Johannsen EC, Kenney SC. Epstein-Barr virus LMP1 protein promotes proliferation and inhibits differentiation of epithelial cells via activation of YAP and TAZ. Proc Natl Acad Sci U S A 2023; 120:e2219755120. [PMID: 37155846 PMCID: PMC10193989 DOI: 10.1073/pnas.2219755120] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 02/28/2023] [Indexed: 05/10/2023] Open
Abstract
Latent Epstein-Barr virus (EBV) infection promotes undifferentiated nasopharyngeal carcinomas (NPCs) in humans, but the mechanism(s) for this effect has been difficult to study because EBV cannot transform normal epithelial cells in vitro and the EBV genome is often lost when NPC cells are grown in culture. Here we show that the latent EBV protein, LMP1 (Latent membrane protein 1), induces cellular proliferation and inhibits spontaneous differentiation of telomerase-immortalized normal oral keratinocytes (NOKs) in growth factor-deficient conditions by increasing the activity of the Hippo pathway effectors, YAP (Yes-associated protein) and TAZ (Transcriptional coactivator with PDZ-binding motif). We demonstrate that LMP1 enhances YAP and TAZ activity in NOKs both by decreasing Hippo pathway-mediated serine phosphorylation of YAP and TAZ and increasing Src kinase-mediated Y357 phosphorylation of YAP. Furthermore, knockdown of YAP and TAZ is sufficient to reduce proliferation and promote differentiation in EBV-infected NOKs. We find that YAP and TAZ are also required for LMP1-induced epithelial-to-mesenchymal transition. Importantly, we demonstrate that ibrutinib (an FDA-approved BTK inhibitor that blocks YAP and TAZ activity through an off-target effect) restores spontaneous differentiation and inhibits proliferation of EBV-infected NOKs at clinically relevant doses. These results suggest that LMP1-induced YAP and TAZ activity contributes to the development of NPC.
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Affiliation(s)
- Deo R. Singh
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Scott E. Nelson
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Abigail S. Pawelski
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Alisha S. Kansra
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Stuart A. Fogarty
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Jillian A. Bristol
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Makoto Ohashi
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Eric C. Johannsen
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
| | - Shannon C. Kenney
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
- Department of Medicine, University of Wisconsin School of Medicine and Public Health, WIMR II, Madison, WI53705
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3
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Hayman IR, Temple RM, Burgess CK, Ferguson M, Liao J, Meyers C, Sample CE. New insight into Epstein-Barr virus infection using models of stratified epithelium. PLoS Pathog 2023; 19:e1011040. [PMID: 36630458 PMCID: PMC9873185 DOI: 10.1371/journal.ppat.1011040] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 01/24/2023] [Accepted: 12/01/2022] [Indexed: 01/12/2023] Open
Abstract
Epstein-Barr virus (EBV) is a ubiquitous human pathogen that is transmitted in saliva. EBV transits through the oral epithelium to infect B cells, where it establishes a life-long latent infection. Reinfection of the epithelium is believed to be mediated by virus shed from B cells, but whether a latent reservoir can exist in the epithelia is unknown. We previously developed an in vitro organotypic model of stratified epithelium where EBV can readily replicate within the suprabasal layers of the epithelium following apical infection mediated by virus-producing B cells. Given that infected epithelial cells and cell-free virus are observed in saliva, we examined the ability of both of these to mediate infection in organotypic cultures. Epithelial-derived cell-free virus was able to infect organotypic cultures from the apical surface, but showed enhanced infection of B cells. Conversely, B cell-derived virus exhibited enhanced infection of epithelial cells. While EBV has been detected in basal cells in oral hairy leukoplakia, it is unknown whether EBV can be seen in undifferentiated primary keratinocytes in the basal layer. Undifferentiated epithelial cells expressed proposed EBV receptors in monolayer and were susceptible to viral binding and entry. Integrins, and occasionally ephrin A2, were expressed in the basal layer of gingiva and tonsil derived organotypic cultures, but the known B-cell receptors HLAII and CD21 were not detected. Following infection with cell-free virus or virus-producing B cells at either the apical or basolateral surface of preformed organotypic cultures, abundant infection was detected in differentiated suprabasal cells while more limited but readily detectable infection was observed in the undifferentiated basal cells. Together, our data has provided new insight into EBV infection in stratified epithelium.
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Affiliation(s)
- Ian R. Hayman
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
| | - Rachel M. Temple
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
| | - Cole K. Burgess
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
| | - Mary Ferguson
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
| | - Jason Liao
- Department of Public Health Sciences, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
- The Penn State Cancer Institute, Hershey, Pennsylvania, United States of America
| | - Craig Meyers
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
- The Penn State Cancer Institute, Hershey, Pennsylvania, United States of America
| | - Clare E. Sample
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
- The Penn State Cancer Institute, Hershey, Pennsylvania, United States of America
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4
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Ward BJH, Schaal DL, Nkadi EH, Scott RS. EBV Association with Lymphomas and Carcinomas in the Oral Compartment. Viruses 2022; 14:2700. [PMID: 36560704 PMCID: PMC9783324 DOI: 10.3390/v14122700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 11/21/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022] Open
Abstract
Epstein-Barr virus (EBV) is an oncogenic human herpesvirus infecting approximately 90% of the world's population. The oral cavity serves a central role in the life cycle, transmission, and pathogenesis of EBV. Transmitted to a new host via saliva, EBV circulates between cellular compartments within oral lymphoid tissues. Epithelial cells primarily support productive viral replication, while B lymphocytes support viral latency and reactivation. EBV infections are typically asymptomatic and benign; however, the latent virus is associated with multiple lymphomas and carcinomas arising in the oral cavity. EBV association with cancer is complex as histologically similar cancers often test negative for the virus. However, the presence of EBV is associated with distinct features in certain cancers. The intrinsic ability of EBV to immortalize B-lymphocytes, via manipulation of survival and growth signaling, further implicates the virus as an oncogenic cofactor. A distinct mutational profile and burden have been observed in EBV-positive compared to EBV-negative tumors, suggesting that viral infection can drive alternative pathways that converge on oncogenesis. Taken together, EBV is also an important prognostic biomarker that can direct alternative therapeutic approaches. Here, we discuss the prevalence of EBV in oral malignancies and the EBV-dependent mechanisms associated with tumorigenesis.
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Affiliation(s)
| | | | | | - Rona S. Scott
- Department of Microbiology and Immunology, Center for Applied Immunology and Pathological Processes, Feist-Weiller Cancer Center, Louisiana State University Health-Shreveport, Shreveport, LA 71103, USA
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5
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EBV persistence in gastric cancer cases conventionally classified as EBER-ISH negative. Infect Agent Cancer 2022; 17:57. [DOI: 10.1186/s13027-022-00469-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
Abstract
Abstract
Background
The Epstein-Barr virus (EBV) causes various B-cell lymphomas and epithelial malignancies, including gastric cancer (GC) at frequencies ranging from 5 to 10% in adenocarcinomas (ADK) to 80% in GC with lymphoid stroma (GCLS). Using high-sensitivity methods, we recently detected EBV traces in a large cohort of EBV-negative B-cell lymphomas, suggesting a hit-and-run mechanism.
Methods
Here, we used routine and higher-sensitivity methods [droplet digital PCR (ddPCR) for EBV segments on microdissected tumour cells and RNAscope for EBNA1 mRNA] to assess EBV infection in a cohort of 40 GCs (28 ADK and 12 GCLS).
Results
ddPCR documented the presence of EBV nucleic acids in rare tumour cells of several cases conventionally classified as EBV-negative (ADK, 8/26; GCLS, 6/7). Similarly, RNAscope confirmed EBNA1 expression in rare tumour cells (ADK, 4/26; GCLS, 3/7). Finally, since EBV induces epigenetic changes that are heritable and retained after complete loss of the virus from the host cell, we studied the methylation pattern of EBV-specifically methylated genes (Timp2, Eya1) as a mark of previous EBV infection. Cases with EBV traces showed a considerable level of methylation in Timp2 and Eya1 genes that was similar to that observed in EBER-ISH positive cases and greater than cases not featuring any EBV traces.
Conclusions
These findings suggest that: (a) EBV may contribute to gastric pathogenesis more widely than currently acknowledged and (b) indicate the methylation changes as a mechanistic framework for how EBV can act in a hit-and-run manner. Finally, we found that the viral state was of prognostic significance in univariate and multivariate analyses.
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Rahman R, Gopinath D, Buajeeb W, Poomsawat S, Johnson NW. Potential Role of Epstein–Barr Virus in Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma: A Scoping Review. Viruses 2022; 14:v14040801. [PMID: 35458531 PMCID: PMC9032208 DOI: 10.3390/v14040801] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/31/2022] [Accepted: 04/01/2022] [Indexed: 12/25/2022] Open
Abstract
Though the oral cavity is anatomically proximate to the nasal cavity and acts as a key reservoir of EBV habitation and transmission, it is still unclear whether EBV plays a significant role in oral carcinogenesis. Many studies have detected EBV DNA in tissues and exfoliated cells from OSCC patients. However, very few studies have investigated the expression of functional EBV proteins implicated in its oncogenicity. The most studied are latent membrane protein 1 (LMP-1), a protein associated with the activation of signalling pathways; EBV determined nuclear antigen (EBNA)-1, a protein involved in the regulation of gene expression; and EBV-encoded small non-polyadenylated RNA (EBER)-2. LMP-1 is considered the major oncoprotein, and overexpression of LMP-1 observed in OSCC indicates that this molecule might play a significant role in oral carcinogenesis. Although numerous studies have detected EBV DNA and proteins from OSCC and oral potentially malignant disorders, heterogeneity in methodologies has led to discrepant results, hindering interpretation. Elucidating the exact functions of EBV and its proteins when expressed is vital in establishing the role of viruses in oral oncogenesis. This review summarises the current evidence on the potential role of EBV in oral oncogenesis and discusses the implications as well as recommendations for future research.
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Affiliation(s)
- Rifat Rahman
- Menzies Health Institute Queensland, School of Medicine and Dentistry, Griffith University, Gold Coast, QLD 4222, Australia; (R.R.); (N.W.J.)
| | - Divya Gopinath
- Clinical Oral Health Sciences Division, School of Dentistry, International Medical University, Kuala Lumpur 57000, Malaysia
- Correspondence:
| | - Waranun Buajeeb
- Department of Oral Medicine and Periodontology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand;
| | - Sopee Poomsawat
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand;
| | - Newell W. Johnson
- Menzies Health Institute Queensland, School of Medicine and Dentistry, Griffith University, Gold Coast, QLD 4222, Australia; (R.R.); (N.W.J.)
- Faculty of Dentistry, Oral and Craniofacial Sciences, King’s College London, London WC2R 2LS, UK
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7
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Virus-host interactions in carcinogenesis of Epstein-Barr virus-associated gastric carcinoma: Potential roles of lost ARID1A expression in its early stage. PLoS One 2021; 16:e0256440. [PMID: 34469459 PMCID: PMC8409614 DOI: 10.1371/journal.pone.0256440] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 08/08/2021] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) is a distinct molecular subtype of gastric cancer characterized by viral infection and cellular abnormalities, including loss of AT-rich interaction domain 1A (ARID1A) expression (lost ARID1A). To evaluate the significance of lost ARID1A in the development of EBVaGC, we performed in situ hybridization of EBV-encoded RNA (EBER) and immunohistochemistry of ARID1A in the non-neoplastic gastric mucosa and intramucosal cancer tissue of EBVaGC with in vitro infection analysis of ARID1A-knockdown and -knockout gastric cells. Screening of EBER by in situ hybridization revealed a frequency of approximately 0.2% EBER-positive epithelial cells in non-neoplastic gastric mucosa tissue samples. Six small foci of EBV-infected epithelial cells showed two types of histology: degenerated (n = 3) and metaplastic (n = 3) epithelial cells. ARID1A was lost in the former type. In intramucosal EBVaGC, there were ARID1A-lost (n = 5) and -preserved tumors (n = 7), suggesting that ARID1A-lost carcinomas are derived from ARID1A-lost precursor cells in the non-neoplastic mucosa. Lost ARID1A was also observed in non-neoplastic mucosa adjacent to an ARID1A-lost EBVaGC. In vitro experiments using siRNA knockdown and the CRISPR/Cas9-knockout system demonstrated that transient reduction or permanent loss of ARID1A expression markedly increased the efficiency of EBV infection to stomach epithelial cells. Taken together, lost ARID1A plays a role in initiating EBV-driven carcinogenesis in stomach epithelial cells, which develop to a distinct subtype of EBVaGC within the proper mucosal layer. Lost ARID1A is one of the constituents of virus-host interactions in the carcinogenesis of EBVaGC.
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Sinclair AJ. Could Changing the DNA Methylation Landscape Promote the Destruction of Epstein-Barr Virus-Associated Cancers? Front Cell Infect Microbiol 2021; 11:695093. [PMID: 34123880 PMCID: PMC8194487 DOI: 10.3389/fcimb.2021.695093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/10/2021] [Indexed: 11/13/2022] Open
Abstract
DNA methylation at CpG motifs provides an epigenetic route to regulate gene expression. In general, an inverse correlation between DNA hypermethylation at CpG motifs and gene expression is observed. Epstein Barr-virus (EBV) infects people and the EBV genome resides in the nucleus where either its replication cycle initiates or it enters a long-term latency state where the viral genome becomes hypermethylated at CpG motifs. Viral gene expression shows a largely inverse correlation with DNA hypermethylation. DNA methylation occurs through the action of DNA methyl transferase enzymes: writer DNA methyl transferases add methyl groups to specific regions of unmethylated DNA; maintenance DNA methyl transferases reproduce the pattern of DNA methylation during genome replication. The impact of DNA methylation is achieved through the association of various proteins specifically with methylated DNA and their influence on gene regulation. DNA methylation can be changed through altering DNA methyl transferase activity or through the action of enzymes that further modify methylated CpG motifs. Azacytidine prodrugs that are incorporated into CpG motifs during DNA replication are recognized by DNA methyl transferases and block their function resulting in hypomethylation of DNA. EBV-associated cancers have hypermethylated viral genomes and many carcinomas also have highly hypermethylated cellular genomes. Decitabine, a member of the azacytidine prodrug family, reactivates viral gene expression and promotes the recognition of lymphoma cells by virus-specific cytotoxic T-cells. For EBV-associated cancers, the impact of decitabine on the cellular genome and the prospect of combining decitabine with other therapeutic approaches is currently unknown but exciting.
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Affiliation(s)
- Alison J Sinclair
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
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Stanland LJ, Luftig MA. The Role of EBV-Induced Hypermethylation in Gastric Cancer Tumorigenesis. Viruses 2020; 12:v12111222. [PMID: 33126718 PMCID: PMC7693998 DOI: 10.3390/v12111222] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 10/24/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023] Open
Abstract
Epstein–Barr-virus-associated Gastric Cancer (EBVaGC) comprises approximately 10% of global gastric cancers and is known to be the most hypermethylated of all tumor types. EBV infection has been shown to directly induce the hypermethylation of both the host and viral genome following initial infection of gastric epithelial cells. Many studies have been completed in an attempt to identify genes that frequently become hypermethylated and therefore significant pathways that become silenced to promote tumorigenesis. It is clear that EBV-induced hypermethylation silences key tumor suppressor genes, cell cycle genes and cellular differentiation factors to promote a highly proliferative and poorly differentiated cell population. EBV infection has been shown to induce methylation in additional malignancies including Nasopharyngeal Carcinoma and Burkitt’s Lymphoma though not to the same level as in EBVaGC. Lastly, some genes silenced in EBVaGC are common to other heavily methylated tumors such as colorectal and breast tumors; however, some genes are unique to EBVaGC and can provide insights into the major pathways involved in tumorigenesis.
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PI3K/AKT/mTOR signaling in gastric cancer: Epigenetics and beyond. Life Sci 2020; 262:118513. [PMID: 33011222 DOI: 10.1016/j.lfs.2020.118513] [Citation(s) in RCA: 209] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 09/22/2020] [Accepted: 09/22/2020] [Indexed: 02/07/2023]
Abstract
PI3K/AKT/mTOR pathway is one of the most important signaling pathways involved in normal cellular processes. Its aberrant activation modulates autophagy, epithelial-mesenchymal transition, apoptosis, chemoresistance, and metastasis in many human cancers. Emerging evidence demonstrates that some infections as well as epigenetic regulatory mechanisms can control PI3K/AKT/mTOR signaling pathway. In this review, we focused on the role of this pathway in gastric cancer development, prognosis, and metastasis, with an emphasis on epigenetic alterations including DNA methylation, histone modifications, and post-transcriptional modulations through non-coding RNAs fluctuations as well as H. pylori and Epstein-Barr virus infections. Finally, we reviewed different molecular targets and therapeutic agents in clinical trials as a potential strategy for gastric cancer treatment through the PI3K/AKT/mTOR pathway.
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11
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Wang W, Nong L, Liang L, Zheng Y, Li D, Li X, Li T. Extranodal NK/T-cell lymphoma, nasal type without evidence of EBV infection. Oncol Lett 2020; 20:2665-2676. [PMID: 32782583 PMCID: PMC7401002 DOI: 10.3892/ol.2020.11842] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 04/27/2020] [Indexed: 12/18/2022] Open
Abstract
Extranodal natural killer/T cell lymphoma-nasal type (EN-NK/T-NT) is extremely rare in Western countries; however, it is the most common subtype of peripheral T cell lymphoma in China. Despite this, there are a limited number of clinicopathological research studies on Epstein-Barr virus (EBV)-negative EN-NK/T-NTs. EBV-negative EN-NK/T-NT is a rare disease type, which has not been fully investigated. If other diagnostic criteria are met, such as the lesions being located predominantly in the upper aerodigestive tract, the presence of angiocentricity or angioinvasion, necrosis and expression of NK/T-cell phenotype, EN-NK/T-NT may be diagnosed, even if EBV is negative. In the present study, 99 cases of EN-NK/T-NTs were analyzed retrospectively, among which seven cases were EBV-negative EN-NK/T-NTs and selected for further investigation. In addition, the present study reviewed previously published research into EN-NK/T-NT, highlighting that EBV-negative EN-NK/T-NT is rare and that its geographical distribution is mainly in countries in Asia, Central America and South America. Patients with EBV-negative EN-NK/T-NT were all of Chinese ethnicity, with a median age of 32 years and primarily female. Furthermore, these patients shared similar clinicopathological characteristics (such as the tumor occurring mainly in the upper aerodigestive tract, the presence of vascular destruction, necrosis and cytotoxic phenotypes) to patients with EBV-positive EN-NK/T-NT. Immunohistochemistry and molecular analysis results indicated that tumor cells were primarily of NK or cytotoxic T origin; however, EBV-encoded small RNAs were not detected in any of these cases. Among the immunochemistry markers, T-bet was statistical significantly different between EBV-positive and -negative cases. Fluorescence in situ hybridization was also performed in two EBV-negative cases, including one case with a co-deletion of 6q21 and PR/SET domain 1 genes. There was only available follow-up data in 3/5 patients who survived for 37–113 months (median, 40 months). As EN-NK/T-NT can be diagnosed, even when EBV is negative, awareness of this subtype may prevent misdiagnosis or delayed diagnosis.
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Affiliation(s)
- Wei Wang
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Lin Nong
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Li Liang
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Yalin Zheng
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Dong Li
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Xin Li
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Ting Li
- Department of Pathology, Peking University First Hospital, Beijing 100034, P.R. China
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12
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Miliotis CN, Slack FJ. Multi-layered control of PD-L1 expression in Epstein-Barr virus-associated gastric cancer. ACTA ACUST UNITED AC 2020; 6. [PMID: 34212113 PMCID: PMC8244904 DOI: 10.20517/2394-4722.2020.12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gastric cancer (GC) is the fifth most common cancer worldwide. In approximately 10% of GC cases, cancer cells show ubiquitous and monoclonal Epstein-Barr virus (EBV) infection. A significant feature of EBV-associated GC (EBVaGC) is high lymphocytic infiltration and high expression of immune checkpoint proteins, including programmed death-ligand 1 (PD-L1). This highlights EBVaGC as a strong candidate for immune checkpoint blockade therapy. Indeed, several recent studies have shown that EBV positivity in GC correlates with positive response to programmed cell death protein 1 (PD-1)/PD-L1 blockade therapy. Understanding the mechanisms that control PD-L1 expression in EBVaGC can indicate new predictive biomarkers for immunotherapy, as well as therapeutic targets for combination therapy. Various mechanisms have been implicated in PD-L1 expression regulation, including structural variations, post-transcriptional control, oncogenic activation of intrinsic signaling pathways, and increased sensitivity to extrinsic signals. This review provides the most recent updates on the multilayered control of PD-L1 expression in EBVaGC.
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Affiliation(s)
- Christos N Miliotis
- HMS Initiative for RNA Medicine, Department of Pathology, Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Frank J Slack
- HMS Initiative for RNA Medicine, Department of Pathology, Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
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13
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Muncunill J, Baptista MJ, Hernandez-Rodríguez Á, Dalmau J, Garcia O, Tapia G, Moreno M, Sancho JM, Martínez-Picado J, Feliu E, Mate JL, Ribera JM, Navarro JT. Plasma Epstein-Barr Virus Load as an Early Biomarker and Prognostic Factor of Human Immunodeficiency Virus-related Lymphomas. Clin Infect Dis 2020; 68:834-843. [PMID: 29982484 DOI: 10.1093/cid/ciy542] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 06/27/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Epstein-Barr virus (EBV) has been implicated in lymphomagenesis and can be found infecting tumor cells and in plasma at lymphoma diagnosis, especially in human immunodeficiency virus (HIV)-infected patients. Our aim was to evaluate the usefulness of plasma EBV load as biomarker and prognostic factor in HIV-positive patients with lymphomas. METHODS EBV loads were measured by polymerase chain reaction in plasma samples of 81 HIV-positive patients' lymphomas at different moments: within 1 year before lymphoma diagnosis, at diagnosis, and at complete response (CR). Control samples included HIV-negative patients with lymphomas and HIV-positive patients without neoplasia or opportunistic infections. RESULTS HIV-positive patients with lymphomas had more frequently-detectable EBV load at lymphoma diagnosis (53%) than either HIV-negative patients with the same lymphoma type (16%; P < .001) or HIV-positive individuals without neoplasia or opportunistic infection (1.2%; P < .001). HIV-positive lymphoma patients with detectable EBV load in plasma at lymphoma diagnosis had statistically significant decrease of EBV load at CR. High EBV load (>5000 copies/mL) at lymphoma diagnosis was an independent negative prognostic factor for overall survival and progression-free survival in HIV-positive patients with lymphomas. Detectable plasma EBV loads identified HIV-positive subjects that would eventually develop lymphoma (area under the curve, 82%; 95% CI: 0.67-0.96). CONCLUSIONS Plasma EBV load can be used as a biomarker and as a prognostic factor in HIV-positive patients with lymphomas. The presence of the EBV load in the plasma of an HIV-positive patient can be an early predictor of lymphoma development.
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Affiliation(s)
- Josep Muncunill
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | - Maria-Joao Baptista
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | | | - Judith Dalmau
- IrsiCaixa AIDS Research Institute, Universitat Autònoma de Barcelona, Badalona
| | - Olga Garcia
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | - Gustavo Tapia
- Department of Pathology, Germans Trias i Pujol Hospital, Universitat Autònoma de Barcelona, Badalona
| | - Miriam Moreno
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | - Juan-Manuel Sancho
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | - Javier Martínez-Picado
- IrsiCaixa AIDS Research Institute, Universitat Autònoma de Barcelona, Badalona.,University of Vic-Central University of Catalonia, Vic.,Catalan Institution for Research and Advanced Studies, Barcelona, Spain
| | - Evarist Feliu
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | - José-Luis Mate
- Department of Pathology, Germans Trias i Pujol Hospital, Universitat Autònoma de Barcelona, Badalona
| | - Josep-Maria Ribera
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
| | - José-Tomás Navarro
- Department of Hematology, Institut Català d'Oncologia-Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona.,Josep Carreras Leukaemia Research Institute, IJC Can Ruti Campus
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14
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Rahman R, Poomsawat S, Juengsomjit R, Buajeeb W. Overexpression of Epstein-Barr virus-encoded latent membrane protein-1 (LMP-1) in oral squamous cell carcinoma. BMC Oral Health 2019; 19:142. [PMID: 31291930 PMCID: PMC6621935 DOI: 10.1186/s12903-019-0832-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 06/24/2019] [Indexed: 12/11/2022] Open
Abstract
Background As oral cavity is the main location of Epstein-Barr virus (EBV) latency and shedding, and as EBV-encoded latent membrane protein-1 (LMP-1) has a crucial role in cell transformation, association between EBV infection, LMP-1 expression and oral malignancy is of interest. Although EBV DNA has been detected in oral squamous cell carcinoma (OSCC), studies on LMP-1 expression in OSCC and oral potentially malignant disorders are scarce and still controversial. This study aimed to evaluate the expression of LMP-1 in OSCC and oral leukoplakia (OL). Methods Biopsy specimens of 36 OSCC, 69 OL with and without dysplasia and 10 normal oral mucosa were assessed for the expression of LMP-1 using immunohistochemistry. In each case, at least 1000 cells were counted. Cells with staining were considered positive, classified by location as nuclear, cytoplasmic and nuclear plus cytoplasmic staining. Percentage of positive cells at different locations and of total positive cells were determined. For statistical analysis, SPSS version 21 was used. Statistical significance was considered at p < 0.05. Results LMP-1 was expressed in all studied specimens. In terms of percentage of total positive cells, LMP-1 expression was higher from normal mucosa (26.36%), OL without dysplasia (28.03%), OL with dysplasia (34.15%), to the significantly highest, (59.67%) in OSCC. In addition, cells with nuclear staining alone, cytoplasmic staining alone and cells with nuclear plus cytoplasmic staining were significantly higher in OSCC compared to those of normal mucosa, OL with and without dysplasia. Conclusions LMP-1 was overexpressed in OSCC. Our analysis on subcellular localization of LMP-1 in OSCC revealed prominent distinguished pattern, cytoplasmic distribution. Further studies in cell lines and animals are required to clarify the association between this EBV-encoded proteins and oral carcinogenesis.
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Affiliation(s)
- Rifat Rahman
- Department of Oral Medicine and Periodontology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand
| | - Sopee Poomsawat
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand
| | - Rachai Juengsomjit
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand
| | - Waranun Buajeeb
- Department of Oral Medicine and Periodontology, Faculty of Dentistry, Mahidol University, Bangkok, 10400, Thailand.
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15
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Inhibition of Epstein-Barr Virus Replication in Human Papillomavirus-Immortalized Keratinocytes. J Virol 2019; 93:JVI.01216-18. [PMID: 30381489 DOI: 10.1128/jvi.01216-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/15/2018] [Indexed: 12/14/2022] Open
Abstract
Epstein-Barr virus (EBV) is implicated in the pathogenesis of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OSCC). EBV-associated cancers harbor a latent EBV infection characterized by a lack of viral replication and the expression of viral oncogenes. Cellular changes promoted by HPV are comparable to those shown to facilitate EBV latency, though whether HPV-positive cells support a latent EBV infection has not been demonstrated. Using a model of direct EBV infection into HPV16-immortalized tonsillar cells grown in organotypic raft culture, we showed robust EBV replication in HPV-negative rafts but little to no replication in HPV-immortalized rafts. The reduced EBV replication was independent of immortalization, as human telomerase-immortalized normal oral keratinocytes supported robust EBV replication. Furthermore, we observed reduced EBV lytic gene expression and increased expression of EBER1, a noncoding RNA highly expressed in latently infected cells, in the presence of HPV. The use of human foreskin keratinocyte rafts expressing the HPV16 E6 and/or E7 oncogene(s) (HPV E6 and E7 rafts) showed that E7 was sufficient to reduce EBV replication. EBV replication is dependent upon epithelial differentiation and the differentiation-dependent expression of the transcription factors KLF4 and PRDM1. While KLF4 and PRDM1 levels were unaltered, the expression levels of KLF4 transcriptional targets, including late differentiation markers, were reduced in HPV E6 and E7 rafts compared to their levels in parental rafts. However, the HPV E7-mediated block in EBV replication correlated with delayed expression of early differentiation markers. Overall, this study reveals an HPV16-mediated block in EBV replication, through E7, that may facilitate EBV latency and long-term persistence in the tumor context.IMPORTANCE Using a model examining the establishment of EBV infection in HPV-immortalized tissues, we showed an HPV-induced interruption of the normal EBV life cycle reminiscent of a latent EBV infection. Our data support the notion that a persistent EBV epithelial infection depends upon preexisting cellular alterations and suggest the ability of HPV to promote such changes. More importantly, these findings introduce a model for how EBV coinfection may influence HPV-positive (HPV-pos) OSCC pathogenesis. Latently EBV-infected epithelial cells, as well as other EBV-associated head-and-neck carcinomas, exhibit oncogenic phenotypes commonly seen in HPV-pos OSCC. Therefore, an HPV-induced shift in the EBV life cycle toward latency would not only facilitate EBV persistence but also provide additional viral oncogene expression, which can contribute to the rapid progression of HPV-pos OSCC. These findings provide a step toward defining a role for EBV as a cofactor in HPV-positive oropharyngeal tumors.
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Charostad J, Astani A, Goudarzi H, Faghihloo E. DNA methyltransferases in virus-associated cancers. Rev Med Virol 2018; 29:e2022. [PMID: 30511446 DOI: 10.1002/rmv.2022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 10/24/2018] [Accepted: 10/24/2018] [Indexed: 12/19/2022]
Abstract
Human tumor viruses are either casually linked or contribute in the development of human cancers. Viruses can stimulate oncogenesis through affecting diverse biological pathways in human cells. Growing data have demonstrated frequent involvement of one of the most characteristic parts of cellular epigenetic machinery, DNA methylation, in the oncogenesis. DNA methylation of cellular genes is catalyzed by DNA methyltransferases (DNMTs) as a key effector enzyme in this process. Dysregulation of DNMTs can cause aberrant gene methylation in promoter of cancer-related genes including tumor suppressor genes, resulting in gene silencing. In this regard, the role of tumor viruses is remarkable. Here, in this review, we used published information to elucidate whether tumor viruses are able to manipulate DNMT regulation, and if so, what are its consequences in the process of oncogenesis. This essay also aims to shed light on which cellular pathways have been engaged by viruses to induce DNMTs.
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Affiliation(s)
- Javad Charostad
- Department of Virology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Akram Astani
- Zoonotic Diseases Research Center, School of Public Health, Sahid Sadoughi University of Medical Sciences, Yazd, Iran.,Department of Microbiology, Shahid Sadoghi University of Medical Science, Yazd, Iran
| | - Hossein Goudarzi
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ebrahim Faghihloo
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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17
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Stanland LJ, Luftig MA. Molecular features and translational outlook for Epstein-Barr virus-associated gastric cancer. Future Virol 2018; 13:803-818. [PMID: 34367314 PMCID: PMC8345226 DOI: 10.2217/fvl-2018-0071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Epstein-Barr Virus (EBV) was the first discovered human tumor virus and is the etiological agent of B cell lymphomas and also epithelial cancers. Indeed, nearly 10% of gastric cancers worldwide are EBV-positive and display unique molecular, epigenetic, and clinicopathological features. EBV-positive gastric cancers display the highest rate of host genome methylation of all tumor types studied and harbor recurrent mutations activating PI3Kα, silencing ARID1A, and amplifying PD-L1. While EBV infection of B cells can be studied efficiently, de novo epithelial cell infection is much more difficult. We propose that new culture models including 3D-based gastric organoids and xenografts can bring new insight into EBV-induced gastric carcinogenesis and will lead to improved precision medicine-based therapies for patients with EBV-positive gastric cancer.
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Affiliation(s)
- Lyla J. Stanland
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Micah A. Luftig
- Department of Molecular Genetics and Microbiology, Center for Virology, Duke University School of Medicine, Durham, NC, 27710, USA
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18
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Zhou J, Zhao GL, Wang XM, Du XS, Su S, Li CG, Nair V, Yao YX, Cheng ZQ. Synergistic Viral Replication of Marek's Disease Virus and Avian Leukosis Virus Subgroup J is Responsible for the Enhanced Pathogenicity in the Superinfection of Chickens. Viruses 2018; 10:E271. [PMID: 29783672 PMCID: PMC5977264 DOI: 10.3390/v10050271] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 05/09/2018] [Accepted: 05/15/2018] [Indexed: 12/13/2022] Open
Abstract
Superinfection of Marek's disease virus (MDV) and avian leukosis virus subgroup J (ALV-J) causes lethal neoplasia and death in chickens. However, whether there is synergism between the two viruses in viral replication and pathogenicity has remained elusive. In this study, we found that the superinfection of MDV and ALV-J increased the viral replication of the two viruses in RNA and protein level, and synergistically promoted the expression of IL-10, IL-6, and TGF-β in chicken embryo fibroblasts (CEF). Moreover, MDV and ALV-J protein expression in dual-infected cells detected by confocal laser scanning microscope appeared earlier in the cytoplasm and the nucleus, and caused more severe cytopathy than single infection, suggesting that synergistically increased MDV and ALV-J viral-protein biosynthesis is responsible for the severe cytopathy. In vivo, compared to the single virus infected chickens, the mortality and tumor formation rates increased significantly in MDV and ALV-J dual-infected chickens. Viral loads of MDV and ALV-J in tissues of dual-infected chickens were significantly higher than those of single-infected chickens. Histopathology observation showed that more severe inflammation and tumor cells metastases were present in dual-infected chickens. In the present study, we concluded that synergistic viral replication of MDV and ALV-J is responsible for the enhanced pathogenicity in superinfection of chickens.
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Affiliation(s)
- Jing Zhou
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
| | - Guo-Liang Zhao
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
| | - Xiao-Man Wang
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
| | - Xu-Sheng Du
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
| | - Shuai Su
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
| | - Chen-Gui Li
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Tai'an 271018, China.
| | - Venugopal Nair
- The Pirbright Institute & UK-China Centre of Excellence on Avian Disease Research, Pirbright, Ash Road, Guildford, Surrey GU24 0NF, UK.
| | - Yong-Xiu Yao
- The Pirbright Institute & UK-China Centre of Excellence on Avian Disease Research, Pirbright, Ash Road, Guildford, Surrey GU24 0NF, UK.
| | - Zi-Qiang Cheng
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Tai'an 271018, China.
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19
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Guidry JT, Birdwell CE, Scott RS. Epstein-Barr virus in the pathogenesis of oral cancers. Oral Dis 2018; 24:497-508. [PMID: 28190296 PMCID: PMC5554094 DOI: 10.1111/odi.12656] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 01/30/2017] [Accepted: 01/31/2017] [Indexed: 12/28/2022]
Abstract
Epstein-Barr virus (EBV) is a ubiquitous gamma-herpesvirus that establishes a lifelong persistent infection in the oral cavity and is intermittently shed in the saliva. EBV exhibits a biphasic life cycle, supported by its dual tropism for B lymphocytes and epithelial cells, which allows the virus to be transmitted within oral lymphoid tissues. While infection is often benign, EBV is associated with a number of lymphomas and carcinomas that arise in the oral cavity and at other anatomical sites. Incomplete association of EBV in cancer has questioned if EBV is merely a passenger or a driver of the tumorigenic process. However, the ability of EBV to immortalize B cells and its prevalence in a subset of cancers has implicated EBV as a carcinogenic cofactor in cellular contexts where the viral life cycle is altered. In many cases, EBV likely acts as an agent of tumor progression rather than tumor initiation, conferring malignant phenotypes observed in EBV-positive cancers. Given that the oral cavity serves as the main site of EBV residence and transmission, here we review the prevalence of EBV in oral malignancies and the mechanisms by which EBV acts as an agent of tumor progression.
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Affiliation(s)
- Joseph T. Guidry
- Department of Microbiology and Immunology, Center for Tumor and Molecular Virology, and Feist-Weiller Cancer Center. Louisiana State University Health Sciences Center-Shreveport. Shreveport, LA 71103
| | - Christine E. Birdwell
- Department of Microbiology and Immunology, Center for Tumor and Molecular Virology, and Feist-Weiller Cancer Center. Louisiana State University Health Sciences Center-Shreveport. Shreveport, LA 71103
| | - Rona S. Scott
- Department of Microbiology and Immunology, Center for Tumor and Molecular Virology, and Feist-Weiller Cancer Center. Louisiana State University Health Sciences Center-Shreveport. Shreveport, LA 71103
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20
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Tsao SW, Tsang CM, Lo KW. Epstein-Barr virus infection and nasopharyngeal carcinoma. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0270. [PMID: 28893937 DOI: 10.1098/rstb.2016.0270] [Citation(s) in RCA: 380] [Impact Index Per Article: 54.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2017] [Indexed: 12/24/2022] Open
Abstract
Epstein-Barr virus (EBV) is associated with multiple types of human cancer, including lymphoid and epithelial cancers. The closest association with EBV infection is seen in undifferentiated nasopharyngeal carcinoma (NPC), which is endemic in the southern Chinese population. A strong association between NPC risk and the HLA locus at chromosome 6p has been identified, indicating a link between the presentation of EBV antigens to host immune cells and NPC risk. EBV infection in NPC is clonal in origin, strongly suggesting that NPC develops from the clonal expansion of a single EBV-infected cell. In epithelial cells, the default program of EBV infection is lytic replication. However, latent infection is the predominant mode of EBV infection in NPC. The establishment of latent EBV infection in pre-invasive nasopharyngeal epithelium is believed to be an early stage of NPC pathogenesis. Recent genomic study of NPC has identified multiple somatic mutations in the upstream negative regulators of NF-κB signalling. Dysregulated NF-κB signalling may contribute to the establishment of latent EBV infection in NPC. Stable EBV infection and the expression of latent EBV genes are postulated to drive the transformation of pre-invasive nasopharyngeal epithelial cells to cancer cells through multiple pathways.This article is part of the themed issue 'Human oncogenic viruses'.
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Affiliation(s)
- Sai Wah Tsao
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Chi Man Tsang
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Kwok Wai Lo
- Department of Anatomical and Cellular Pathology and State Key Laboratory in Oncology in South China, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR
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21
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22
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Epstein-Barr virus stably confers an invasive phenotype to epithelial cells through reprogramming of the WNT pathway. Oncotarget 2018. [PMID: 29535816 PMCID: PMC5828208 DOI: 10.18632/oncotarget.23824] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Epstein-Barr virus (EBV)-associated carcinomas, such as nasopharyngeal carcinoma (NPC), exhibit an undifferentiated and metastatic phenotype. To determine viral contributions involved in the invasive phenotype of EBV-associated carcinomas, EBV-infected human telomerase-immortalized normal oral keratinocytes (NOK) were investigated. EBV-infected NOK were previously shown to undergo epigenetic reprogramming involving CpG island hypermethylation and delayed responsiveness to differentiation. Here, we show that EBV-infected NOK acquired an invasive phenotype that was epigenetically retained after viral loss. The transcription factor lymphoid enhancer factor 1 (LEF1) and the secreted ligand WNT5A, expressed in NPC, were increased in EBV-infected NOK with sustained expression for more than 20 passages after viral loss. Increased LEF1 levels involved four LEF1 variants, and EBV-infected NOK showed a lack of responsiveness to β-catenin activation. Although forced expression of WNT5A and LEF1 enhanced the invasiveness of parental NOK, LEF1 knockdown reversed the invasive phenotype of EBV-infected NOK in the presence of WNT5A. Viral reprogramming of LEF1 and WNT5A was observed several passages after EBV infection, suggesting that LEF1 and WNT5A may provide a selective advantage to virally-infected cells. Our findings suggest that EBV epigenetically reprogrammed epithelial cells with features of basal, wound healing keratinocytes, with LEF1 contributing to the metastatic phenotype of EBV-associated carcinomas.
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23
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Shannon-Lowe C, Rickinson AB, Bell AI. Epstein-Barr virus-associated lymphomas. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160271. [PMID: 28893938 PMCID: PMC5597738 DOI: 10.1098/rstb.2016.0271] [Citation(s) in RCA: 247] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2017] [Indexed: 02/06/2023] Open
Abstract
Epstein-Barr virus (EBV), originally discovered through its association with Burkitt lymphoma, is now aetiologically linked to a remarkably wide range of lymphoproliferative lesions and malignant lymphomas of B-, T- and NK-cell origin. Some occur as rare accidents of virus persistence in the B lymphoid system, while others arise as a result of viral entry into unnatural target cells. The early finding that EBV is a potent B-cell growth transforming agent hinted at a simple oncogenic mechanism by which this virus could promote lymphomagenesis. In reality, the pathogenesis of EBV-associated lymphomas involves a complex interplay between different patterns of viral gene expression and cellular genetic changes. Here we review recent developments in our understanding of EBV-associated lymphomagenesis in both the immunocompetent and immunocompromised host.This article is part of the themed issue 'Human oncogenic viruses'.
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Affiliation(s)
- Claire Shannon-Lowe
- Institute of Immunology and Immunotherapy, The Medical School, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Alan B Rickinson
- Institute of Immunology and Immunotherapy, The Medical School, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Andrew I Bell
- Institute for Cancer and Genomic Sciences, The Medical School, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Cappa R, Theroux L, Brenton JN. Pediatric Multiple Sclerosis: Genes, Environment, and a Comprehensive Therapeutic Approach. Pediatr Neurol 2017; 75:17-28. [PMID: 28843454 DOI: 10.1016/j.pediatrneurol.2017.07.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 06/03/2017] [Accepted: 07/06/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Pediatric multiple sclerosis is an increasingly recognized and studied disorder that accounts for 3% to 10% of all patients with multiple sclerosis. The risk for pediatric multiple sclerosis is thought to reflect a complex interplay between environmental and genetic risk factors. MAIN FINDINGS Environmental exposures, including sunlight (ultraviolet radiation, vitamin D levels), infections (Epstein-Barr virus), passive smoking, and obesity, have been identified as potential risk factors in youth. Genetic predisposition contributes to the risk of multiple sclerosis, and the major histocompatibility complex on chromosome 6 makes the single largest contribution to susceptibility to multiple sclerosis. With the use of large-scale genome-wide association studies, other non-major histocompatibility complex alleles have been identified as independent risk factors for the disease. The bridge between environment and genes likely lies in the study of epigenetic processes, which are environmentally-influenced mechanisms through which gene expression may be modified. CONCLUSIONS This article will review these topics to provide a framework for discussion of a comprehensive approach to counseling and ultimately treating the pediatric patient with multiple sclerosis.
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Affiliation(s)
- Ryan Cappa
- Department of Neurology, Division of Pediatric Neurology, University of Virginia, Charlottesville, Virginia
| | - Liana Theroux
- Department of Neurology, Division of Pediatric Neurology, University of Virginia, Charlottesville, Virginia
| | - J Nicholas Brenton
- Department of Neurology, Division of Pediatric Neurology, University of Virginia, Charlottesville, Virginia.
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25
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Epstein-Barr virus: a master epigenetic manipulator. Curr Opin Virol 2017; 26:74-80. [PMID: 28780440 DOI: 10.1016/j.coviro.2017.07.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/10/2017] [Accepted: 07/18/2017] [Indexed: 12/29/2022]
Abstract
Like all herpesviruses, the ability of Epstein-Barr virus (EBV) to establish life-long persistent infections is related to a biphasic viral lifecycle that involves latency and reactivation/lytic replication. Memory B cells serve as the EBV latency compartment where silencing of viral gene expression allows maintenance of the viral genome, avoidance of immune surveillance, and life-long carriage. Upon viral reactivation, viral gene expression is induced for replication, progeny virion production, and viral spread. EBV uses the host epigenetic machinery to regulate its distinct viral gene expression states. However, epigenetic manipulation by EBV affects the host epigenome by reprogramming cells in ways that leave long-lasting, oncogenic phenotypes. Such virally-induced epigenetic alterations are evident in EBV-associated cancers.
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26
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Mundo L, Ambrosio MR, Picciolini M, Lo Bello G, Gazaneo S, Del Porro L, Lazzi S, Navari M, Onyango N, Granai M, Bellan C, De Falco G, Gibellini D, Piccaluga PP, Leoncini L. Unveiling Another Missing Piece in EBV-Driven Lymphomagenesis: EBV-Encoded MicroRNAs Expression in EBER-Negative Burkitt Lymphoma Cases. Front Microbiol 2017; 8:229. [PMID: 28298901 PMCID: PMC5331039 DOI: 10.3389/fmicb.2017.00229] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/01/2017] [Indexed: 12/20/2022] Open
Abstract
Epstein–Barr virus (EBV) is a gammaherpesvirus linked to a number of lymphoid and epithelial malignancies, including Burkitt lymphoma (BL) in which its frequency ranges from 30% in sporadic cases to 100% in the endemic ones. The possible contribution of EBV to BL pathogenesis is largely unknown. It has been suggested that EBV may be associated with all of the cases, including those diagnosed as EBV negative by a mechanism of hit-and-run. Early during oncogenesis, viral genes are essential for initiating disease. Progressively, viral genome is lost to escape the immune system and host mutations accumulate in proto-oncogenic cell. The main problem with the hit-and-run hypothesis is the lack of evidence in primary tumors. The routine methods applied to detect the virus [i.e., immunohistochemistry and EBV-encoded RNAs (EBER) in situ hybridization (ISH)] have a low specificity and accuracy. The aim of this study was to identify the most suitable method to detect EBV infection in pathology samples by applying conventional and non-conventional methods (i.e., EBV-microRNAs detection and EBV viral load measurement). We investigated a total of 10 cases and we found that all the samples (n = 6) diagnosed as EBV negative by immunohistochemistry and EBER-ISH demonstrated the presence of EBV-microRNAs and EBV genome. This points at the possibility that EBV might have contributed to lymphomagenesis in all our patients, and propose microRNAs detection as the most specific and sensitive tool to recognize EBV vestiges. It is worth noting that our data would have considerable implications for EBV-related diseases control. By using anti-EBV vaccines, one could potentially prevent also some cancers less suspected of a viral origin because of viral genome loss.
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Affiliation(s)
- Lucia Mundo
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Maria R Ambrosio
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | | | - Giuseppe Lo Bello
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Sara Gazaneo
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Leonardo Del Porro
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Stefano Lazzi
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Mohsen Navari
- Department of Experimental, Diagnostic, and Experimental Medicine, S. Orsola-Malpighi Hospital, Bologna University School of Medicine Bologna, Italy
| | - Noel Onyango
- Department of Clinical Medicine and Therapeutics, University of Nairobi Nairobi, Kenya
| | - Massimo Granai
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Cristiana Bellan
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
| | - Giulia De Falco
- School of Biological and Chemical Sciences, Queen Mary University of London London, UK
| | - Davide Gibellini
- Virology Unit, Department of Diagnostic and Public Health, University of Verona Verona, Italy
| | - Pier P Piccaluga
- Department of Experimental, Diagnostic, and Experimental Medicine, S. Orsola-Malpighi Hospital, Bologna University School of MedicineBologna, Italy; Euro-Mediterranean Institute of Science and TechnologyPalermo, Italy
| | - Lorenzo Leoncini
- Section of Pathology, Department of Medical Biotechnology, University of Siena Siena, Italy
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Guidry JT, Scott RS. The interaction between human papillomavirus and other viruses. Virus Res 2016; 231:139-147. [PMID: 27826043 DOI: 10.1016/j.virusres.2016.11.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 10/28/2016] [Accepted: 11/03/2016] [Indexed: 12/12/2022]
Abstract
The etiological role of human papillomavirus (HPV) in anogenital tract and head and neck cancers is well established. However, only a low percentage of HPV-positive women develop cancer, indicating that HPV is necessary but not sufficient in carcinogenesis. Several biological and environmental cofactors have been implicated in the development of HPV-associated carcinoma that include immune status, hormonal changes, parity, dietary habits, tobacco usage, and co-infection with other sexually transmissible agents. Such cofactors likely contribute to HPV persistent infection through diverse mechanisms related to immune control, efficiency of HPV infection, and influences on tumor initiation and progression. Conversely, HPV co-infection with other factors may also harbor anti-tumor effects. Here, we review epidemiological and experimental studies investigating human immunodeficiency virus (HIV), herpes simplex virus (HSV) 1 and 2, human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), BK virus (BKV), JC virus (JCV), and adeno-associated virus (AAV) as viral cofactors in or therapeutic factors against the development of genital and oral HPV-associated carcinomas.
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Affiliation(s)
- J T Guidry
- Department of Microbiology and Immunology, Center for Tumor and Molecular Virology, and Feist-Weiller Cancer Center. Louisiana State University Health Sciences Center-Shreveport. Shreveport, LA 71103, USA
| | - R S Scott
- Department of Microbiology and Immunology, Center for Tumor and Molecular Virology, and Feist-Weiller Cancer Center. Louisiana State University Health Sciences Center-Shreveport. Shreveport, LA 71103, USA.
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Dykes SS, Gao C, Songock WK, Bigelow RL, Woude GV, Bodily JM, Cardelli JA. Zinc finger E-box binding homeobox-1 (Zeb1) drives anterograde lysosome trafficking and tumor cell invasion via upregulation of Na+/H+ Exchanger-1 (NHE1). Mol Carcinog 2016; 56:722-734. [PMID: 27434882 DOI: 10.1002/mc.22528] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 06/28/2016] [Accepted: 07/11/2016] [Indexed: 01/25/2023]
Abstract
Tumor cell invasion through the extracellular matrix is facilitated by the secretion of lysosome-associated proteases. As a common mechanism for secretion, lysosomes must first traffic to the cell periphery (anterograde trafficking), consistent with invasive cells often containing lysosomes closer to the plasma membrane compared to non-invasive cells. Epithelial to mesenchymal transition (EMT) is a transcriptionally driven program that promotes an invasive phenotype, and Zeb1 is one transcription factor that activates the mesenchymal gene expression program. The role of lysosome trafficking in EMT-driven invasion has not been previously investigated. We found that cells with increased levels of Zeb1 displayed lysosomes located closer to the cell periphery and demonstrated increased protease secretion and invasion in 3-dimensional (3D) cultures compared to their epithelial counterparts. Additionally, preventing anterograde lysosome trafficking via pharmacological inhibition of Na+/H+ exchanger 1 (NHE1) or shRNA depletion of ADP-ribosylation like protein 8b (Arl8b) reversed the invasive phenotype of mesenchymal cells, thus supporting a role for lysosome positioning in EMT-mediated tumor cell invasion. Immunoblot revealed that expression of Na+/H+ exchanger 1 correlated with Zeb1 expression. Furthermore, we found that the transcription factor Zeb1 binds to the Na+/H+ exchanger 1 promoter, suggesting that Zeb1 directly controls Na+/H+ transcription. Collectively, these results provide insight into a novel mechanism regulating Na+/H+ exchanger 1 expression and support a role for anterograde lysosome trafficking in Zeb1-driven cancer progression. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Samantha S Dykes
- Department of Microbiology and Immunology, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana.,Feist Weiller Cancer Center, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana
| | - ChongFeng Gao
- Laboratory of Molecular Oncology, Van Andel Research Institute, Grand Rapids, Michigan
| | - William K Songock
- Department of Microbiology and Immunology, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana.,Feist Weiller Cancer Center, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana
| | - Rebecca L Bigelow
- Department of Microbiology and Immunology, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana.,Feist Weiller Cancer Center, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana
| | - George Vande Woude
- Laboratory of Molecular Oncology, Van Andel Research Institute, Grand Rapids, Michigan
| | - Jason M Bodily
- Department of Microbiology and Immunology, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana.,Feist Weiller Cancer Center, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana
| | - James A Cardelli
- Department of Microbiology and Immunology, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana.,Feist Weiller Cancer Center, Louisiana State University Health Science Center - Shreveport, Shreveport, Louisiana
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Anandharaj A, Ekshyyan O, Jia Y, Rong X, Harrison L, Shi R, Scott RS, Nathan CAO. EBV and not HPV sensitizes tobacco-associated head and neck cancer cell line FaDu to radiotherapy. Acta Otolaryngol 2015; 136:354-62. [PMID: 26635065 DOI: 10.3109/00016489.2015.1114182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Conclusion EBV radiosensitized the p53 mutant tobacco associated head and neck cell line, FaDu. Objectives In the head and neck, HPV is a major risk factor associated with tonsil and base of tongue cancers, while a majority of undifferentiated nasopharyngeal cancers are positive for EBV. Clinically, head and neck tumors positive for HPV or EBV are more radiosensitive than tumors associated with tobacco and alcohol. This study aimed to evaluate whether viral infections can sensitize tobacco-associated head and neck squamous cell carcinoma cell line that harbors multiple mutations, especially TP53, to radiotherapy. Method Four FaDu cell lines (vector control - FaDu-DN; FaDu expressing HPV16 E6/E7 - FaDu-HPV; FaDu infected with EBV - FaDu-EBV; and FaDu-HPV infected with EBV - FaDu-HE) were evaluated for their radiation sensitivity using clonogenic assay. Cell cycle, protein expression, apoptosis, and cellular senescence were analyzed. Results FaDu-EBV and FaDu-HE exhibited significantly increased radiosensitivity in comparison with the control cell line. Radiation-induced cell cycle arrest was altered in all cell lines expressing viral genes. The observed distribution of cells at G1 and S phases was associated with a significant increase in expression of p21 protein along with decreased levels of pAKT/AKT and pERK/ERK ratio (p < 0.05) and increased cellular senescence (p < 0.05).
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Affiliation(s)
| | - Oleksandr Ekshyyan
- a Department of Otolaryngology , Head and Neck Surgery
- b Feist-Weiller Cancer Center
| | - Yali Jia
- c Department of Microbiology and Immunology
| | - Xiaohua Rong
- a Department of Otolaryngology , Head and Neck Surgery
- b Feist-Weiller Cancer Center
| | - Lynn Harrison
- d Department of Molecular and Cellular Physiology , LSU Health - Shreveport , Shreveport , LA , USA
| | | | - Rona S Scott
- b Feist-Weiller Cancer Center
- c Department of Microbiology and Immunology
| | - Cherie-Ann O Nathan
- a Department of Otolaryngology , Head and Neck Surgery
- b Feist-Weiller Cancer Center
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Abstract
DNA tumor viruses including members of the polyomavirus, adenovirus, papillomavirus, and herpes virus families are presently the subject of intense interest with respect to the role that epigenetics plays in control of the virus life cycle and the transformation of a normal cell to a cancer cell. To date, these studies have primarily focused on the role of histone modification, nucleosome location, and DNA methylation in regulating the biological consequences of infection. Using a wide variety of strategies and techniques ranging from simple ChIP to ChIP-chip and ChIP-seq to identify histone modifications, nuclease digestion to genome wide next generation sequencing to identify nucleosome location, and bisulfite treatment to MeDIP to identify DNA methylation sites, the epigenetic regulation of these viruses is slowly becoming better understood. While the viruses may differ in significant ways from each other and cellular chromatin, the role of epigenetics appears to be relatively similar. Within the viral genome nucleosomes are organized for the expression of appropriate genes with relevant histone modifications particularly histone acetylation. DNA methylation occurs as part of the typical gene silencing during latent infection by herpesviruses. In the simple tumor viruses like the polyomaviruses, adenoviruses, and papillomaviruses, transformation of the cell occurs via integration of the virus genome such that the virus's normal regulation is disrupted. This results in the unregulated expression of critical viral genes capable of redirecting cellular gene expression. The redirected cellular expression is a consequence of either indirect epigenetic regulation where cellular signaling or transcriptional dysregulation occurs or direct epigenetic regulation where epigenetic cofactors such as histone deacetylases are targeted. In the more complex herpersviruses transformation is a consequence of the expression of the viral latency proteins and RNAs which again can have either a direct or indirect effect on epigenetic regulation of cellular expression. Nevertheless, many questions still remain with respect to the specific mechanisms underlying epigenetic regulation of the viruses and transformation.
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Niller HH, Tarnai Z, Decsi G, Zsedényi A, Bánáti F, Minarovits J. Role of epigenetics in EBV regulation and pathogenesis. Future Microbiol 2015; 9:747-56. [PMID: 25046522 DOI: 10.2217/fmb.14.41] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epigenetic modifications of the viral and host cell genomes regularly occur in EBV-associated lymphomas and carcinomas. The cell type-dependent usage of latent EBV promoters is determined by the cellular epigenetic machinery. Viral oncoproteins interact with the very same epigenetic regulators and alter the cellular epigenotype and gene-expression pattern: there are common gene sets hypermethylated in both EBV-positive and EBV-negative neoplasms of different histological types. A group of hypermethylated promoters may represent, however, a unique EBV-associated epigenetic signature in EBV-positive gastric carcinomas. By contrast, EBV-immortalized B-lymphoblastoid cell lines are characterized by genome-wide demethylation and loss and rearrangement of heterochromatic histone marks. Early steps of EBV infection may also contribute to reprogramming of the cellular epigenome.
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Affiliation(s)
- Hans Helmut Niller
- Department of Microbiology & Hygiene, University of Regensburg, Franz-Josef-Strauss Allee 11, D-93053 Regensburg, Germany
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Kaposi's sarcoma-associated herpesvirus genome programming during the early stages of primary infection of peripheral blood mononuclear cells. mBio 2014; 5:mBio.02261-14. [PMID: 25516617 PMCID: PMC4271552 DOI: 10.1128/mbio.02261-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The early period of Kaposi’s sarcoma-associated herpesvirus (KSHV) infection involves the dynamic expression of viral genes, which are temporally and epigenetically regulated. KSHV can effectively infect and persist in endothelial as well as human B cells with different gene expression patterns. To understand the temporal epigenetic changes which occur when KSHV infects the lymphocytic compartment, we infected human peripheral blood mononuclear cells (PBMCs) and comprehensively analyzed the changes which occurred at the binding sites of virally encoded lytic as well as latent proteins along with epigenetic modifications across the KSHV genome during early primary infection. Using chromatin immunoprecipitation (ChIP) assays, we showed that the KSHV genome acquires a uniquely distinct histone modification pattern of methylation (H3K4me3, H3K9me3, and H3K27me3) and acetylation (H3Ac) during de novo infection of human PBMCs. This pattern showed that the epigenetic changes were temporally controlled. The binding profiles of KSHV latent protein LANA and the immediate early proteins RTA and K8 showed specific patterns at different times postinfection, which reflects the gene expression program. Further analysis demonstrated that KSHV can concurrently express lytic and latent genes which were associated with histone modifications at these specific regions on the viral genome. We identified three KSHV genes, K3, ORF49, and ORF64, which exhibited different profiles of histone modifications during the early stages of PBMC infection. These studies established a distinct pattern of epigenetic modification which correlates with viral gene expression temporally regulated during the first 7 days of PBMC infection and provides clues to the regulatory program required for successful infection by KSHV of human PBMCs. Kaposi’s sarcoma-associated herpesvirus (KSHV) has been documented as one of the major contributors to morbidity and mortality in AIDS patients during the AIDS pandemic. During its life cycle, KSHV undergoes latent and lytic replication. Typically, KSHV maintains a stringent preference for latent infection in the infected B cells. However, 1 to 5% of infected cells undergo spontaneous lytic reactivation. KSHV lytic replication and infection of new cells are likely to be critical for maintaining the population of infected cells which drive virus-associated pathogenesis. Here, we explored the temporal changes of crucial histone marks on the KSHV genome during early infection of human primary peripheral blood mononuclear cells (PBMCs), which are a physiologically relevant system for monitoring primary infection. These results showed that KSHV possessed a distinct pattern of epigenetic marks during early infection of PBMCs. Further, KSHV concurrently expressed lytic and latent genes during this early period. These results now provide new evidence which contributes to understanding the molecular mechanism that regulates viral gene expression during early infection.
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Fritsch P, Craddock TJA, del Rosario RM, Rice MA, Smylie A, Folcik VA, de Vries G, Fletcher MA, Klimas NG, Broderick G. Succumbing to the laws of attraction. ACTA ACUST UNITED AC 2014. [DOI: 10.4161/sysb.28948] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Niller HH, Szenthe K, Minarovits J. Epstein-Barr virus-host cell interactions: an epigenetic dialog? Front Genet 2014; 5:367. [PMID: 25400657 PMCID: PMC4212275 DOI: 10.3389/fgene.2014.00367] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/02/2014] [Indexed: 12/23/2022] Open
Abstract
Here, we wish to highlight the genetic exchange and epigenetic interactions between Epstein–Barr virus (EBV) and its host. EBV is associated with diverse lymphoid and epithelial malignancies. Their molecular pathogenesis is accompanied by epigenetic alterations which are distinct for each of them. While lymphoblastoid cell lines derived from B cells transformed by EBV in vitro are characterized by a massive demethylation and euchromatinization of the viral and cellular genomes, the primarily malignant lymphoid tumor Burkitt’s lymphoma and the epithelial tumors nasopharyngeal carcinoma and EBV-associated gastric carcinoma are characterized by hypermethylation of a multitude of cellular tumor suppressor gene loci and of the viral genomes. In some cases, the viral latency and oncoproteins including the latent membrane proteins LMP1 and LMP2A and several nuclear antigens affect the level of cellular DNA methyltransferases or interact with the histone modifying machinery. Specific molecular mechanisms of the epigenetic dialog between virus and host cell remain to be elucidated.
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Affiliation(s)
- Hans H Niller
- Institute of Medical Microbiology and Hygiene, University of Regensburg , Regensburg, Germany
| | - Kalman Szenthe
- RT-Europe Nonprofit Research Ltd, Mosonmagyaróvár , Hungary
| | - Janos Minarovits
- Department of Oral Biology and Experimental Dental Research, Faculty of Dentistry, University of Szeged , Szeged, Hungary
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Genome-wide DNA methylation as an epigenetic consequence of Epstein-Barr virus infection of immortalized keratinocytes. J Virol 2014; 88:11442-58. [PMID: 25056883 DOI: 10.1128/jvi.00972-14] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
UNLABELLED The oral cavity is a persistent reservoir for Epstein-Barr virus (EBV) with lifelong infection of resident epithelial and B cells. Infection of these cell types results in distinct EBV gene expression patterns regulated by epigenetic modifications involving DNA methylation and chromatin structure. Regulation of EBV gene expression relies on viral manipulation of the host epigenetic machinery that may result in long-lasting host epigenetic reprogramming. To identify epigenetic events following EBV infection, a transient infection model was established to map epigenetic changes in telomerase-immortalized oral keratinocytes. EBV-infected oral keratinocytes exhibited a predominantly latent viral gene expression program with some lytic or abortive replication. Calcium and methylcellulose-induced differentiation was delayed in EBV-positive clones and in clones that lost EBV compared to uninfected controls, indicating a functional consequence of EBV epigenetic modifications. Analysis of global cellular DNA methylation identified over 13,000 differentially methylated CpG residues in cells exposed to EBV compared to uninfected controls, with CpG island hypermethylation observed at several cellular genes. Although the vast majority of the DNA methylation changes were silent, 65 cellular genes that acquired CpG methylation showed altered transcript levels. Genes with increased transcript levels frequently acquired DNA methylation within the gene body while those with decreased transcript levels acquired DNA methylation near the transcription start site. Treatment with the DNA methyltransferase inhibitor, decitabine, restored expression of some hypermethylated genes in EBV-infected and EBV-negative transiently infected clones. Overall, these observations suggested that EBV infection of keratinocytes leaves a lasting epigenetic imprint that can enhance the tumorigenic phenotype of infected cells. IMPORTANCE Here, we show that EBV infection of oral keratinocytes led to CpG island hypermethylation as an epigenetic scar of prior EBV infection that was retained after loss of the virus. Such EBV-induced epigenetic modification recapitulated the hypermethylated CpG island methylator phenotype (CIMP) observed in EBV-associated carcinomas. These epigenetic alterations not only impacted gene expression but also resulted in delayed calcium and methylcellulose-induced keratinocyte differentiation. Importantly, these epigenetic changes occurred in cells that were not as genetically unstable as carcinoma cells, indicating that EBV infection induced an epigenetic mutator phenotype. The impact of this work is that we have provided a mechanistic framework for how a tumor virus using the epigenetic machinery can act in a "hit-and-run" fashion, with retention of epigenetic alterations after loss of the virus. Unlike genetic alterations, these virally induced epigenetic changes can be reversed pharmacologically, providing therapeutic interventions to EBV-associated malignancies.
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Jiang R, Ekshyyan O, Moore-Medlin T, Rong X, Nathan S, Gu X, Abreo F, Rosenthal EL, Shi M, Guidry JT, Scott RS, Hutt-Fletcher LM, Nathan CAO. Association between human papilloma virus/Epstein-Barr virus coinfection and oral carcinogenesis. J Oral Pathol Med 2014; 44:28-36. [PMID: 25040496 DOI: 10.1111/jop.12221] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2014] [Indexed: 12/14/2022]
Abstract
BACKGROUND The recent epidemic of head and neck squamous cell carcinomas associated with human papilloma virus (HPV) has not addressed its association with lymphoid tissue in the oropharynx or the potential role of Epstein-Barr virus (EBV)/HPV coinfection. METHODS The prevalence of HPV and EBV infection/coinfection and CD21 mRNA expression were determined in normal and cancerous tissues from the oropharynx using in situ hybridization (ISH), p16, and quantitative reverse transcriptase PCR (qRT-PCR). The effects of coinfection on tumorigenicity were evaluated using proliferation and invasion assays. RESULTS Normal oropharynx, tonsil, non-cancer base of tongue (BOT), and BOT from sleep apnea patients demonstrated EBV positivity ranging from 7% to 36% depending on the site and methods of detection used (qRT-PCR or ISH). Among non-malignant BOT samples, HPV positivity was noted only in 20%. The percent of tonsil and BOT cancers positive for HPV (up to 63% and 80%, respectively) or coinfected with HPV/EBV (up to 25% and 70%, respectively) were both significantly associated with cancer status. Notably, HPV/EBV coinfection was observed only in malignant tissue originating in lymphoid-rich oropharynx sites (tonsil, BOT). CD21 mRNA (the major EBV attachment receptor) was detected in tonsil and BOT epithelium, but not in soft-palate epithelium. Coinfected cell lines showed a significant increase in invasiveness (P < 0.01). CONCLUSIONS There is a high prevalence of HPV/EBV infection and coinfection in BOT and tonsil cancers, possibly reflecting their origins in lymphoid-rich tissue. In vitro, cells modeling coinfection have an increased invasive potential.
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Affiliation(s)
- Ru Jiang
- Department of Microbiology and Immunology, LSUHSC, Shreveport, LA, USA; Department of Clinical Teaching and Training, Tianjin University of Traditional Chinese Medicine, Tianjin, China
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Shapiro JA. Epigenetic control of mobile DNA as an interface between experience and genome change. Front Genet 2014; 5:87. [PMID: 24795749 PMCID: PMC4007016 DOI: 10.3389/fgene.2014.00087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 04/01/2014] [Indexed: 12/29/2022] Open
Abstract
Mobile DNA in the genome is subject to RNA-targeted epigenetic control. This control regulates the activity of transposons, retrotransposons and genomic proviruses. Many different life history experiences alter the activities of mobile DNA and the expression of genetic loci regulated by nearby insertions. The same experiences induce alterations in epigenetic formatting and lead to trans-generational modifications of genome expression and stability. These observations lead to the hypothesis that epigenetic formatting directed by non-coding RNA provides a molecular interface between life history events and genome alteration.
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Affiliation(s)
- James A. Shapiro
- Department of Biochemistry and Molecular Biology, University of ChicagoChicago, IL, USA
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Craddock TJA, Fritsch P, Rice MA, del Rosario RM, Miller DB, Fletcher MA, Klimas NG, Broderick G. A role for homeostatic drive in the perpetuation of complex chronic illness: Gulf War Illness and chronic fatigue syndrome. PLoS One 2014; 9:e84839. [PMID: 24416298 PMCID: PMC3885655 DOI: 10.1371/journal.pone.0084839] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 11/19/2013] [Indexed: 12/15/2022] Open
Abstract
A key component in the body's stress response, the hypothalamic-pituitary-adrenal (HPA) axis orchestrates changes across a broad range of major biological systems. Its dysfunction has been associated with numerous chronic diseases including Gulf War Illness (GWI) and chronic fatigue syndrome (CFS). Though tightly coupled with other components of endocrine and immune function, few models of HPA function account for these interactions. Here we extend conventional models of HPA function by including feed-forward and feedback interaction with sex hormone regulation and immune response. We use this multi-axis model to explore the role of homeostatic regulation in perpetuating chronic conditions, specifically GWI and CFS. An important obstacle in building these models across regulatory systems remains the scarcity of detailed human in vivo kinetic data as its collection can present significant health risks to subjects. We circumvented this using a discrete logic representation based solely on literature of physiological and biochemical connectivity to provide a qualitative description of system behavior. This connectivity model linked molecular variables across the HPA axis, hypothalamic-pituitary-gonadal (HPG) axis in men and women, as well as a simple immune network. Inclusion of these interactions produced multiple alternate homeostatic states and sexually dimorphic responses. Experimental data for endocrine-immune markers measured in male GWI subjects showed the greatest alignment with predictions of a naturally occurring alternate steady state presenting with hypercortisolism, low testosterone and a shift towards a Th1 immune response. In female CFS subjects, expression of these markers aligned with an alternate homeostatic state displaying hypocortisolism, high estradiol, and a shift towards an anti-inflammatory Th2 activation. These results support a role for homeostatic drive in perpetuating dysfunctional cortisol levels through persistent interaction with the immune system and HPG axis. Though coarse, these models may nonetheless support the design of robust treatments that might exploit these regulatory regimes.
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Affiliation(s)
- Travis J. A. Craddock
- Center for Psychological Studies, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
- Graduate School for Computer and Information Sciences, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
- Institute for Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
- * E-mail:
| | - Paul Fritsch
- Department of Medicine, Faculty of Dentistry and Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Mark A. Rice
- Institute for Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
| | - Ryan M. del Rosario
- Institute for Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
| | - Diane B. Miller
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, West Virginia, United States of America
| | - Mary Ann Fletcher
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Nancy G. Klimas
- Institute for Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
- College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
| | - Gordon Broderick
- Center for Psychological Studies, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
- Institute for Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
- Department of Medicine, Faculty of Dentistry and Medicine, University of Alberta, Edmonton, Alberta, Canada
- College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida, United States of America
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Farina A, Cirone M, York M, Lenna S, Padilla C, Mclaughlin S, Faggioni A, Lafyatis R, Trojanowska M, Farina GA. Epstein-Barr virus infection induces aberrant TLR activation pathway and fibroblast-myofibroblast conversion in scleroderma. J Invest Dermatol 2013; 134:954-964. [PMID: 24129067 PMCID: PMC3961515 DOI: 10.1038/jid.2013.423] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 09/16/2013] [Accepted: 09/17/2013] [Indexed: 12/28/2022]
Abstract
Scleroderma (SSc) is a complex and heterogeneous connective tissue disease mainly characterized by autoimmunity, vascular damage, and fibrosis that mostly involve the skin and lungs. Epstein–Barr virus (EBV) is a lymphotropic γ-herpesvirus that has co-evolved with human species, infecting >95% of the adult population worldwide, and has been a leading candidate in triggering several autoimmune diseases. Here we show that EBV establishes infection in the majority of fibroblasts and endothelial cells in the skin of SSc patients, characterized by the expression of the EBV noncoding small RNAs (EBERs) and the increased expression of immediate-early lytic and latency mRNAs and proteins. We report that EBV is able to persistently infect human SSc fibroblasts in vitro, inducing an aberrant innate immune response in infected cells. EBV–Toll-like receptor (TLR) aberrant activation induces the expression of selected IFN-regulatory factors (IRFs), IFN-stimulated genes (ISGs), transforming growth factor-β1 (TGFβ1), and several markers of fibroblast activation, such as smooth muscle actin and Endothelin-1, and all of these genes play a key role in determining the profibrotic phenotype in SSc fibroblasts. These findings imply that EBV infection occurring in mesenchymal, endothelial, and immune cells of SSc patients may underlie the main pathological features of SSc including autoimmunity, vasculopathy, and fibrosis, and provide a unified disease mechanism represented by EBV reactivation.
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Affiliation(s)
- Antonella Farina
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA; Institute Pasteur-Fondazione Cenci Bolognetti, Department of Experimental Medicine, University of Rome Sapienza, Rome, Italy
| | - Mara Cirone
- Institute Pasteur-Fondazione Cenci Bolognetti, Department of Experimental Medicine, University of Rome Sapienza, Rome, Italy
| | - Michael York
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Stefania Lenna
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Cristina Padilla
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Sarah Mclaughlin
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Alberto Faggioni
- Institute Pasteur-Fondazione Cenci Bolognetti, Department of Experimental Medicine, University of Rome Sapienza, Rome, Italy
| | - Robert Lafyatis
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Maria Trojanowska
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Giuseppina A Farina
- Rheumatology Section, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
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Wong AMG, Kong KL, Chen L, Liu M, Wong AMG, Zhu C, Tsang JWH, Guan XY. Characterization ofCACNA2D3as a putative tumor suppressor gene in the development and progression of nasopharyngeal carcinoma. Int J Cancer 2013; 133:2284-95. [DOI: 10.1002/ijc.28252] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 04/04/2013] [Indexed: 12/31/2022]
Affiliation(s)
| | | | | | | | | | | | | | - Xin-Yuan Guan
- Department of Clinical Oncology; The University of Hong Kong; Hong Kong; China
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