A Positive Autoregulatory Loop of LMP1 Expression and STAT Activation in Epithelial Cells Latently Infected with Epstein-Barr Virus

ABSTRACT STAT3 and STAT5 are constitutively activated and nuclear in nasopharyngeal carcinoma (NPC) cells. In normal signaling, STATs are only transiently activated. To investigate whether Epstein-Barr virus (EBV), and in particular the protein LMP1, contributes to sustained STAT phosphorylation and activation in epithelial cells, we examined STAT activity in two sets of paired cell lines, HeLa, an EBV-converted HeLa cell line, HeLa-Bx1, the NPC-derived cell line CNE2-LNSX, and an LMP1-expressing derivative, CNE2-LMP1. EBV infection was associated with a significant increase in the tyrosine-phosphorylated forms of STAT3 and STAT5 in HeLa-Bx1 cells. This effect correlated with LMP1 expression, since phosphorylated STAT3 and STAT5 levels were also increased in CNE2-LMP1 cells relative to the control CNE2-LNSX cells. No change was observed in STAT1 or STAT6 phosphorylation in these cell lines, nor was there a significant change in the levels of total STAT3, STAT5, STAT1, or STAT6 protein. Tyrosine phosphorylation allows the normally cytoplasmic STAT proteins to enter the nucleus and bind to their recognition sequences in responsive promoters. The ability of LMP1 to activate STAT3 was further established by immunofluorescence assays in which coexpression of LMP1 in transfected cells was sufficient to mediate nuclear relocalization of Flag-STAT3 and by an electrophoretic mobility shift assay which showed that LMP1 expression in CNE2-LNSX cells was associated with increased endogenous STAT3 DNA binding activity. In addition, the activity of a downstream target of STAT3, c-Myc, was upregulated in HeLa-Bx1 and CNE2-LMP1 cells. A linkage was established between interleukin-6 (IL-6)- and LMP1-mediated STAT3 activation. Treatment with IL-6 increased phosphorylated STAT3 levels in CNE2-LNSX cells, and conversely, treatment of CNE2-LMP1 cells with IL-6 neutralizing antibody ablated STAT3 activation and c-Myc upregulation. The previous observation that STAT3 activated the LMP1 terminal repeat promoter in reporter assays was extended to show upregulated expression of endogenous LMP1 mRNA and protein in HeLa-Bx1 cells transfected with a constitutively activated STAT3. A model is proposed in which EBV infection of an epithelial cell containing activated STATs would permit LMP1 expression. This in turn would establish a positive feedback loop of IL-6-induced STAT activation, LMP1 and Qp-EBNA1 expression, and viral genome persistence.

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Analysis of Epstein-Barr Virus Infections in Lymphoma Cell Lines.

Blood ◽

10.1182/blood.v106.11.3906.3906 ◽

2005 ◽

Vol 106 (11) ◽

pp. 3906-3906

Author(s):

Cord C. Uphoff ◽

Sabine A. Denkmann ◽

Hans G. Drexler

Keyword(s):

Cell Line ◽

B Lymphocytes ◽

Cell Lines ◽

Epstein Barr Virus ◽

Human Populations ◽

Cell Leukemia ◽

Linear Dna ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr

Abstract Epstein-Barr virus (EBV, human herpesvirus type 4) is ubiquitously distributed in all human populations, reaching infection rates of more than 90%. EBV is known to infect B- lymphocytes and mucosal epithelium cells and to establish latent or productive infections. The virus is the causative agent of infectious mononucleosis and closely associated with the endemic form of Burkitt lymphoma (BL). EBV has also been associated with various lymphoid and epithelial malignancies, such as Hodgkin, T-cell, and AIDS-related lymphomas, and lymphoepithelioma-like carcinomas of several organs. In vitro, B- lymphocytes are transformed by EBV into permanent lymphoblastoid cell lines (B-LCL). We investigated the EBV infection status of primate cell lines by PCR (406 human, 4 monkey). This method detects EBV genomes integrated into the eukaryotic chromosomes, non-integrated EBV episomes, and linear genomes of active EBV particles. The analyses revealed that 38/410 cell lines contain the EBV genome. All EBV+ cell lines were established from B- lineage leukemia/lymphoma cells (13/52 B-non-Hodgkin cell lines, 10/13 BL cell lines, 2/2 hairy cell leukemia cell lines, 1/6 plasma cell leukemia/myeloma cell lines) or are B-LCLs (9/9), natural killer cells (2/2), and one monkey cell line. No cell lines from other tissues were found to be EBV+. To further examine the production of EBV particles in the PCR+ cell lines, we analyzed the expression of the BZLF1 protein by Western blotting applying a ZEBRA monoclonal antibody. The cell lines were analyzed untreated as well as treated with the phorbol ester TPA for 3 days to induce the lytic phase of the EBV infection. Four cell lines exhibited a BZLF1 specific band a priori; after stimulation with TPA, 4 further cell lines expressed BZLF1 protein to various extents. To distinguish between linear DNA of herpesviruses (DNA form of active viruses) and covalently closed circles of episomal DNA, we performed Gardella gels applying crude lysates from cell cultures. Except for cell line NAMALWA and its subclones, DG-75, DOHH-2, and OCI-LY19 (all EBV-PCR+ cell lines) showed at least one band of episomal genomes. Some cell lines showed two episomal bands pointing to a double infection or to mutated episomes. The amount of linear DNA does not correlate with the number of episomes. Southern blots of genomic DNA revealed different genotypes of EBV, except for those cell lines which were established with B95-8 virus particles. To determine distribution of EBV genomes in single cells, we established a fluorescence in situ hybridization (FISH) method with a Cy3-labeled cosmid clone containing a genomic EBV fragment. The method showed for various cell lines that only a few cells contain high amounts of EBV genomes (several hundred) whereas the vast majority harbors only a few genomes in the nuclei. FISH appears to be superior to other methods, allowing for EBV analysis at the single cell level to determine the cellular permissiveness. In summary, we could show that EBV is constitutively produced in a few B-lymphoma derived cell lines and can be induced in several other cell lines. These cell lines represent valuable tools for further investigation into the biology of EBV infection.

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Epstein-Barr Virus Infection in Ex Vivo Tonsil Epithelial Cell Cultures of Asymptomatic Carriers

Journal of Virology ◽

10.1128/jvi.78.22.12613-12624.2004 ◽

2004 ◽

Vol 78 (22) ◽

pp. 12613-12624 ◽

Cited By ~ 72

Author(s):

Dirk M. Pegtel ◽

Jaap Middeldorp ◽

David A. Thorley-Lawson

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Cell Lines ◽

Cell Cultures ◽

Epstein Barr Virus ◽

Ex Vivo ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr

ABSTRACT Epstein-Barr virus (EBV) is found frequently in certain epithelial pathologies, such as nasopharyngeal carcinoma and oral hairy leukoplakia, indicating that the virus can infect epithelial cells in vivo. Recent studies of cell lines imply that epithelial cells may also play a role in persistent EBV infection in vivo. In this report, we show the establishment and characterization of an ex vivo culture model of tonsil epithelial cells, a likely site for EBV infection in vivo. Primary epithelial-cell cultures, generated from tonsil explants, contained a heterogeneous mixture of cells with an ongoing process of differentiation. Keratin expression profiles were consistent with the presence of cells from both surface and crypt epithelia. A small subset of cells could be latently infected by coculture with EBV-releasing cell lines, but not with cell-free virus. We also detected viral-DNA, -mRNA, and -protein expression in cultures from EBV-positive tonsil donors prior to in vitro infection. We conclude that these cells were either already infected at the time of explantation or soon after through cell-to-cell contact with B cells replicating EBV in the explant. Taken together, these findings suggest that the tonsil epithelium of asymptomatic virus carriers is able to sustain EBV infection in vivo. This provides an explanation for the presence of EBV in naso- and oropharyngeal pathologies and is consistent with epithelial cells playing a role in the egress of EBV during persistent infection.

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Air-Liquid Interface Method To Study Epstein-Barr Virus Pathogenesis in Nasopharyngeal Epithelial Cells

mSphere ◽

10.1128/msphere.00152-18 ◽

2018 ◽

Vol 3 (4) ◽

Cited By ~ 5

Author(s):

Elizabeth A. Caves ◽

Sarah A. Cook ◽

Nara Lee ◽

Donna Stoltz ◽

Simon Watkins ◽

...

Keyword(s):

Epithelial Cells ◽

Infected Cell ◽

Cell Line ◽

Epstein Barr Virus ◽

Culture Method ◽

Liquid Interface ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr ◽

Air Liquid Interface

ABSTRACT Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that establishes a latent reservoir in peripheral B-lymphocytes with sporadic reactivation. EBV also infects epithelial cells, predominantly resulting in a lytic infection, which may contribute to EBV transmission from saliva. In the nasopharynx, EBV infection can lead to the clonal expansion of a latently infected cell and the development of nasopharyngeal carcinoma (NPC). The mechanisms governing EBV pathogenesis in nasopharyngeal epithelium are largely unknown. An advanced understanding would depend on a physiologically relevant culture model of polarized airway epithelium. The recent application of the organotypic raft culture in keratinocytes has demonstrated great promise for the use of polarized cultures in the study of EBV permissive replication. In this study, the adaptation of an air-liquid interface (ALI) culture method using transwell membranes was explored in an EBV-infected NPC cell line. In the EBV-infected NPC HK1 cell line, ALI culture resulted in the completion of EBV reactivation, with global induction of the lytic cascade, replication of EBV genomes, and production of infectious progeny virus. We propose that the ALI culture method can be widely adopted as a physiologically relevant model to study EBV pathogenesis in polarized nasal epithelial cells. IMPORTANCE Lifting adherent cells to the air-liquid interface (ALI) is a method conventionally used to culture airway epithelial cells into polarized apical and basolateral surfaces. Reactivation of Epstein-Barr virus (EBV) from monolayer epithelial cultures is sometimes abortive, which may be attributed to the lack of authentic reactivation triggers that occur in stratified epithelium in vivo. In the present work, the ALI culture method was applied to study EBV reactivation in nasopharyngeal epithelial cells. The ALI culture of an EBV-infected cell line yielded high titers and can be dissected by a variety of molecular virology assays that measure induction of the EBV lytic cascade and EBV genome replication and assembly. EBV infection of polarized cultures of primary epithelial cells can be challenging and can have variable efficiencies. However, the use of the ALI method with established EBV-infected cell lines offers a readily available and reproducible approach for the study of EBV permissive replication in polarized epithelia.

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Epstein-Barr Virus Induces Adhesion Receptor CD226 (DNAM-1) Expression during Primary B-Cell Transformation into Lymphoblastoid Cell Lines

mSphere ◽

10.1128/msphere.00305-17 ◽

2017 ◽

Vol 2 (6) ◽

Cited By ~ 5

Author(s):

Lisa Grossman ◽

Chris Chang ◽

Joanne Dai ◽

Pavel A. Nikitin ◽

Dereje D. Jima ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Cell Lines ◽

Epstein Barr Virus ◽

Human Herpesvirus ◽

Barr Virus ◽

Ebv Infection ◽

Cellular Aggregation ◽

Epstein Barr

ABSTRACT Epstein-Barr virus (EBV) is a common human herpesvirus that establishes latency in B cells. While EBV infection is asymptomatic for most individuals, immune-suppressed individuals are at significantly higher risk of a form of EBV latent infection in which infected B cells are reactivated, grow unchecked, and generate lymphomas. This form of latency is modeled in the laboratory by infecting B cells from the blood of normal human donors in vitro. In this model, we identified a protein called CD226 that is induced by EBV but is not normally expressed on B cells. Rather, it is known to play a role in aggregation and survival signaling of non-B cells in the immune system. Cultures of EBV-infected cells adhere to one another in “clumps,” and while the proteins that are responsible for this cellular aggregation are not fully understood, we hypothesized that this form of cellular aggregation may provide a survival advantage. In this article, we characterize the mechanism by which EBV induces this protein and its expression on lymphoma tissue and cell lines and characterize EBV-infected cell lines in which CD226 has been knocked out. Epstein-Barr virus (EBV), an oncogenic herpesvirus, infects and transforms primary B cells into immortal lymphoblastoid cell lines (LCLs), providing a model for EBV-mediated tumorigenesis. EBV transformation stimulates robust homotypic aggregation, indicating that EBV induces molecules that mediate cell-cell adhesion. We report that EBV potently induced expression of the adhesion molecule CD226, which is not normally expressed on B cells. We found that early after infection of primary B cells, EBV promoted an increase in CD226 mRNA and protein expression. CD226 levels increased further from early proliferating EBV-positive B cells to LCLs. We found that CD226 expression on B cells was independent of B-cell activation as CpG DNA failed to induce CD226 to the extent of EBV infection. CD226 expression was high in EBV-infected B cells expressing the latency III growth program, but low in EBV-negative and EBV latency I-infected B-lymphoma cell lines. We validated this correlation by demonstrating that the latency III characteristic EBV NF-κB activator, latent membrane protein 1 (LMP1), was sufficient for CD226 upregulation and that CD226 was more highly expressed in lymphomas with increased NF-κB activity. Finally, we found that CD226 was not important for LCL steady-state growth, survival in response to apoptotic stress, homotypic aggregation, or adhesion to activated endothelial cells. These findings collectively suggest that EBV induces expression of a cell adhesion molecule on primary B cells that may play a role in the tumor microenvironment of EBV-associated B-cell malignancies or facilitate adhesion in the establishment of latency in vivo. IMPORTANCE Epstein-Barr virus (EBV) is a common human herpesvirus that establishes latency in B cells. While EBV infection is asymptomatic for most individuals, immune-suppressed individuals are at significantly higher risk of a form of EBV latent infection in which infected B cells are reactivated, grow unchecked, and generate lymphomas. This form of latency is modeled in the laboratory by infecting B cells from the blood of normal human donors in vitro. In this model, we identified a protein called CD226 that is induced by EBV but is not normally expressed on B cells. Rather, it is known to play a role in aggregation and survival signaling of non-B cells in the immune system. Cultures of EBV-infected cells adhere to one another in “clumps,” and while the proteins that are responsible for this cellular aggregation are not fully understood, we hypothesized that this form of cellular aggregation may provide a survival advantage. In this article, we characterize the mechanism by which EBV induces this protein and its expression on lymphoma tissue and cell lines and characterize EBV-infected cell lines in which CD226 has been knocked out.

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Hippo signaling effectors YAP and TAZ induce Epstein-Barr Virus (EBV) lytic reactivation through TEADs in epithelial cells

PLoS Pathogens ◽

10.1371/journal.ppat.1009783 ◽

2021 ◽

Vol 17 (8) ◽

pp. e1009783

Author(s):

Nicholas Van Sciver ◽

Makoto Ohashi ◽

Nicholas P. Pauly ◽

Jillian A. Bristol ◽

Scott E. Nelson ◽

...

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

B Cell ◽

Epstein Barr Virus ◽

Hippo Signaling ◽

Oral Keratinocytes ◽

Barr Virus ◽

Ebv Infection ◽

Lytic Reactivation ◽

Epstein Barr

The Epstein-Barr virus (EBV) human herpesvirus is associated with B-cell and epithelial-cell malignancies, and both the latent and lytic forms of viral infection contribute to the development of EBV-associated tumors. Here we show that the Hippo signaling effectors, YAP and TAZ, promote lytic EBV reactivation in epithelial cells. The transcriptional co-activators YAP/TAZ (which are inhibited by Hippo signaling) interact with DNA-binding proteins, particularly TEADs, to induce transcription. We demonstrate that depletion of either YAP or TAZ inhibits the ability of phorbol ester (TPA) treatment, cellular differentiation or the EBV BRLF1 immediate-early (IE) protein to induce lytic EBV reactivation in oral keratinocytes, and show that over-expression of constitutively active forms of YAP and TAZ reactivate lytic EBV infection in conjunction with TEAD family members. Mechanistically, we find that YAP and TAZ interact with, and activate, the EBV BZLF1 immediate-early promoter. Furthermore, we demonstrate that YAP, TAZ, and TEAD family members are expressed at much higher levels in epithelial cell lines in comparison to B-cell lines, and find that EBV infection of oral keratinocytes increases the level of activated (dephosphorylated) YAP and TAZ. Finally, we have discovered that lysophosphatidic acid (LPA), a known YAP/TAZ activator that plays an important role in inflammation, induces EBV lytic reactivation in epithelial cells through a YAP/TAZ dependent mechanism. Together these results establish that YAP/TAZ are powerful inducers of the lytic form of EBV infection and suggest that the ability of EBV to enter latency in B cells at least partially reflects the extremely low levels of YAP/TAZ and TEADs in this cell type.

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Infection of Epstein–Barr Virus in Type III Latency Modulates Biogenesis of Exosomes and the Expression Profile of Exosomal miRNAs in the Burkitt Lymphoma Mutu Cell Lines

Cancers ◽

10.3390/cancers10070237 ◽

2018 ◽

Vol 10 (7) ◽

pp. 237 ◽

Cited By ~ 13

Author(s):

Asuka Nanbo ◽

Harutaka Katano ◽

Michiyo Kataoka ◽

Shiho Hoshina ◽

Tsuyoshi Sekizuka ◽

...

Keyword(s):

Epithelial Cells ◽

Burkitt Lymphoma ◽

Epstein Barr Virus ◽

Type I ◽

Type Iii ◽

Barr Virus ◽

Ebv Infection ◽

Latently Infected ◽

Infected Cells ◽

Epstein Barr

Infection of Epstein–Barr virus (EBV), a ubiquitous human gamma herpesvirus, is associated with various malignancies in B lymphocytes and epithelial cells. EBV encodes 49 microRNAs in two separated regions, termed the BART and BHRF1 loci. Although accumulating evidence demonstrates that EBV infection regulates the profile of microRNAs in the cells, little is known about the microRNAs in exosomes released from infected cells. Here, we characterized the expression profile of intracellular and exosomal microRNAs in EBV-negative, and two related EBV-infected Burkitt lymphoma cell lines having type I and type III latency by next-generation sequencing. We found that the biogenesis of exosomes is upregulated in type III latently infected cells compared with EBV-negative and type I latently infected cells. We also observed that viral and several specific host microRNAs were predominantly incorporated in the exosomes released from the cells in type III latency. We confirmed that multiple viral microRNAs were transferred to the epithelial cells cocultured with EBV-infected B cells. Our findings indicate that EBV infection, in particular in type III latency, modulates the biogenesis of exosomes and the profile of exosomal microRNAs, potentially contributing to phenotypic changes in cells receiving these exosomes.

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Signatures of B-cell receptor diversity in B lymphocytes following Epstein-Barr virus transformation

Physiological Genomics ◽

10.1152/physiolgenomics.00124.2018 ◽

2019 ◽

Vol 51 (6) ◽

pp. 197-207

Author(s):

Meimei Lai ◽

Qiongdan Wang ◽

Yutian Lu ◽

Xi Xu ◽

Ying Xia ◽

...

Keyword(s):

B Cell ◽

Cell Line ◽

Epstein Barr Virus ◽

High Throughput Sequencing ◽

Cell Receptor ◽

B Cell Receptor ◽

Human Virus ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr

Epstein-Barr virus (EBV) is a widespread human virus that establishes latent infection, potentially leading to tumors, hematological disorders, and other severe diseases. EBV infections are associated with diverse symptoms and affect various organs; therefore, early diagnosis and treatment are crucial. B cell receptor (BCR) repertoires of B cell surface immunoglobulins have been widely studied for their association with various infectious diseases. However, the specific genetic changes that modulate the BCR repertoires after an EBV infection are still poorly understood. In this study, we employed high-throughput sequencing (HTS) to investigate the diversity of BCR repertoires in an EBV-transformed lymphoblastic cell line (LCL). Compared with the noninfected control B cell line, the LCL exhibited a decrease in overall BCR diversity but displayed an increase in the expansion of some dominant rearrangements such as IGHV4-31/IGHJ4, IGHV4-59/IGHJ4, IGHV5-51/IGHJ3, and IGHV3-74/IGHJ3. A higher frequency of occurrence of these rearrangement types was confirmed in patients with EBV infection. Interestingly, the IGHV3-74 rearrangement was only detected in EBV-infected children, suggesting that our experimental observations were not coincidental. In addition, we identified a highly dominant consensus motif, CAR(xRx)YGSG(xYx)FD, in complementarity-determining region 3 (CDR3) sequences of the heavy chain in the LCL. Our findings demonstrated the utility of HTS technology for studying the variations in signature motifs of the BCR repertoires after EBV infection. We propose that the analysis of BCR repertoire sequences represents a promising method for diagnosing early EBV infections and developing novel antibody- and vaccine-based therapies against such infections.

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Epstein–Barr Virus Infection of Pseudostratified Nasopharyngeal Epithelium Disrupts Epithelial Integrity

Cancers ◽

10.3390/cancers12092722 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2722

Author(s):

Fenggang Yu ◽

Yanan Lu ◽

Yingying Li ◽

Yuji Uchio ◽

Utomo Andi Pangnguriseng ◽

...

Keyword(s):

Epithelial Cells ◽

Epstein Barr Virus ◽

Basal Layer ◽

Infection Model ◽

Hybridization Technique ◽

Epstein Barr Virus Infection ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr ◽

Nasopharyngeal Epithelial

Epstein–Barr virus (EBV) is a human oncogenic virus that causes several types of tumor, such as Burkitt’s lymphoma and nasopharyngeal carcinoma (NPC). NPC tumor cells are clonal expansions of latently EBV-infected epithelial cells. However, the mechanisms by which EBV transforms the nasopharyngeal epithelium is hampered, because of the lack of good in vitro model to pursue oncogenic process. Our primary nasopharyngeal epithelial cell cultures developed pseudostratified epithelium at the air-liquid interface, which was susceptible to EBV infection. Using the highly sensitive RNA in situ hybridization technique, we detected viral infection in diverse cell types, including ciliated cells, goblet cells, and basal cells. EBV-encoded small RNA-positive cells were more frequently detected in the suprabasal layer than in the basal layer. We established the most physiologically relevant EBV infection model of nasopharyngeal epithelial cells. This model will advance our understanding of EBV pathogenesis in the development of NPC.

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Characterization of naturally Epstein–Barr virus-infected gastric carcinoma cell line YCCEL1

Journal of General Virology ◽

10.1099/vir.0.045237-0 ◽

2013 ◽

Vol 94 (3) ◽

pp. 497-506 ◽

Cited By ~ 32

Author(s):

Do Nyun Kim ◽

Min Koo Seo ◽

Hoyun Choi ◽

Su Yeon Kim ◽

Hee Jong Shin ◽

...

Keyword(s):

Cell Line ◽

Cell Lines ◽

Blot Analysis ◽

Epstein Barr Virus ◽

Model Systems ◽

Nuclear Antigen ◽

Gastric Carcinoma Cell ◽

Barr Virus ◽

Epstein Barr

Epstein–Barr virus (EBV) is a herpesvirus associated with lymphomas and carcinomas. While EBV-associated epithelial cell lines are good model systems to investigate the role of EBV in carcinoma, only a few cell lines are available as they are hard to acquire. A greater variety of naturally EBV-infected cell lines which are derived from tumour patients are needed to represent various features of EBVaGC. We characterized cell line YCCEL1, established from a Korean EBVaGC patient, to ascertain whether it can be used to study the roles of EBV in EBVaGC. The expression of EBV genes and cell surface markers was examined by in situ hybridization, RT-PCR, Western blot analysis, immunofluorescence assay and Northern blot analysis. EBV episomal status was analysed by Southern blotting and real-time PCR. This cell line expressed EBV nuclear antigen 1 (EBNA1) and latent membrane protein 2A (LMP2A), but not EBNA2, LMP2B nor LMP1. The majority of the lytic proteins were not detected in YCCEL1 cells either before or after treatment with 12-O-tetradecanoylphorbol-13-acetate. YCCEL1 cells expressed BART microRNAs (miRNAs) at high level but did not express BHRF1 miRNAs. YCCEL1 cells expressed cytokeratin, but not CD21 and CD19, suggesting CD21-independent EBV infection. The latent EBV gene and EBV miRNA expression pattern of YCCEL1 cells closely resembled that of general EBVaGC cases. Our results support the value of YCCEL1 cells as a good model system to study the role of EBV in gastric carcinogenesis.

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Epstein-Barr-Virus-Encoded LMP2A Induces Primary Epithelial Cell Migration and Invasion: Possible Role in Nasopharyngeal Carcinoma Metastasis

Journal of Virology ◽

10.1128/jvi.79.24.15430-15442.2005 ◽

2005 ◽

Vol 79 (24) ◽

pp. 15430-15442 ◽

Cited By ~ 66

Author(s):

Dirk M. Pegtel ◽

Aravind Subramanian ◽

Tzung-Shiahn Sheen ◽

Ching-Hwa Tsai ◽

Todd R. Golub ◽

...

Keyword(s):

Cell Migration ◽

Epithelial Cell ◽

Epithelial Cells ◽

Epstein Barr Virus ◽

Cellular Migration ◽

Migration And Invasion ◽

Barr Virus ◽

Ebv Infection ◽

Epithelial Cell Migration ◽

Epstein Barr

ABSTRACT Nonkeratinizing nasopharyngeal carcinomas (NPC) are >95% associated with the expression of the Epstein-Barr virus (EBV) LMP2A latent protein. However, the role of EBV, in particular, LMP2A, in tumor progression is not well understood. Using Affymetrix chips and a pattern-matching computational technique (neighborhood analysis), we show that the level of LMP2A expression in NPC biopsy samples correlates with that of a cellular protein, integrin-alpha-6 (ITGα6), that is associated with cellular migration in vitro and metastasis in vivo. We have recently developed a primary epithelial model from tonsil tissue to study EBV infection in epithelial cells. Here we report that LMP2A expression in primary tonsil epithelial cells causes them to become migratory and invasive, that ITGα6 RNA levels are up-regulated in epithelial cells expressing LMP2, and that ITGα6 protein levels are increased in the migrating cells. Blocking antibodies against ITGα6 abrogated LMP2-induced invasion through Matrigel by primary epithelial cells. Our results provide a link between LMP2A expression, ITGα6 expression, epithelial cell migration, and NPC metastasis and suggest that EBV infection may contribute to the high incidence of metastasis in NPC progression.

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