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Kim YS. Gastric Carcinoma. Curr Top Microbiol Immunol 2025. [PMID: 40423781 DOI: 10.1007/82_2025_303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2025]
Abstract
Epstein-Barr virus (EBV)-associated gastric cancers (EBVaGCs) account for about 10% of gastric cancers globally, with higher prevalence in East Asia and Latin America. These cancers develop through a "gastritis-infection-cancer sequence" and are characterized by unique molecular signatures, including CpG island methylator phenotype and mutations in ARID1A and PIK3CA genes. EBVaGCs typically present in the proximal stomach with diffuse-type histology and dense lymphocytic infiltration. Key viral proteins EBNA1 and LMP2A drive oncogenesis by altering cellular processes and immune responses. The IFN-γ signature and extensive epigenetic modifications contribute to their distinct profile. Despite often presenting at advanced stages, EBVaGCs generally have a more favorable prognosis. EBV employs sophisticated strategies to evade immune detection, utilizing latent proteins and noncoding RNAs. Paradoxically, despite an immune-hot environment, EBVaGCs demonstrate effective immune evasion, partly due to the expression of immune checkpoint molecules like PD-L1 and LAG3. Treatment approaches vary based on disease stage, from endoscopic resection for early-stage cancers to systemic therapies for advanced cases. Immunotherapy, particularly PD-1/PD-L1 inhibitors, shows promising results. Emerging research suggests combining these with LAG3 inhibitors may enhance efficacy. Ongoing research and advanced genomic techniques continue to reveal new insights, paving the way for personalized therapies and novel diagnostic approaches.
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Affiliation(s)
- Young-Sik Kim
- Department of Pathology, Korea University Ansan Hospital, Korea University College of Medicine, Seoul, Republic of Korea.
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2
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Sugiokto FG, Li R. Targeting EBV Episome for Anti-Cancer Therapy: Emerging Strategies and Challenges. Viruses 2025; 17:110. [PMID: 39861899 PMCID: PMC11768851 DOI: 10.3390/v17010110] [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: 12/18/2024] [Revised: 01/12/2025] [Accepted: 01/13/2025] [Indexed: 01/27/2025] Open
Abstract
As a ubiquitous human pathogen, the Epstein-Barr virus (EBV) has established lifelong persistent infection in about 95% of the adult population. The EBV infection is associated with approximately 200,000 human cancer cases and 140,000 deaths per year. The presence of EBV in tumor cells provides a unique advantage in targeting the viral genome (also known as episome), to develop anti-cancer therapeutics. In this review, we summarize current strategies targeting the viral episome in cancer cells. We also highlight emerging technologies, such as clustered regularly interspersed short palindromic repeat (CRISPR)-based gene editing or activation, which offer promising avenues for selective targeting of the EBV episome for anti-cancer therapy. We discuss the challenges, limitations, and future perspectives associated with these strategies, including potential off-target effects, anti-cancer efficacy and safety.
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Affiliation(s)
- Febri Gunawan Sugiokto
- Program in Microbiology and Immunology, University of Pittsburgh, Pittsburgh, PA 15219, USA;
- Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, PA 15232, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Renfeng Li
- Program in Microbiology and Immunology, University of Pittsburgh, Pittsburgh, PA 15219, USA;
- Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, PA 15232, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA 15219, USA
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3
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Sugiokto FG, Li R. Targeted eradication of EBV-positive cancer cells by CRISPR/dCas9-mediated EBV reactivation in combination with ganciclovir. mBio 2024; 15:e0079524. [PMID: 38874417 PMCID: PMC11253602 DOI: 10.1128/mbio.00795-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 04/30/2024] [Indexed: 06/15/2024] Open
Abstract
Epstein-Barr virus (EBV) is a ubiquitous human tumor virus that establishes lifelong, persistent infections in B cells. The presence of EBV in cancer cells presents an opportunity to target these cells by reactivating the virus from latency. In this study, we developed a novel approach for EBV reactivation termed clustered regularly interspaced short palindromic repeats (CRISPR)/dCas9-mediated EBV reactivation (CMER) strategy. Using modified CRISPR-associated protein 9 (dCas9) fused with VP64, we designed 10 single guide RNAs (sgRNAs) to target and activate the EBV immediate-early gene promoter. In Akata Burkitt lymphoma cells, 9 out of 10 CMER sgRNAs effectively reactivated EBV. Among these, CMER sgRNA-5 triggered robust reactivation across various cell types, including lymphoma, gastric cancer, and nasopharyngeal carcinoma cells. Importantly, the combination of CMER and ganciclovir selectively eliminated EBV-positive cells, regardless of their cell origin. These findings indicate that targeted virus reactivation by CMER, combined with nucleoside analog therapy, holds promise for EBV-associated cancer treatment. IMPORTANCE This study explores a novel strategy called clustered regularly interspaced short palindromic repeats (CRISPR)/dCas9-mediated Epstein-Barr virus (EBV) reactivation (CMER) to reactivate the Epstein-Barr virus in cancer cells. EBV is associated with various cancers, and reactivating EBV from latency offers a potential therapeutic strategy. We utilized an enzymatically inactive CRISPR-associated protein 9 (dCas9) fused with VP64 and designed 10 single guide RNAs to target the EBV immediate-early gene promoter. Nine of these sgRNAs effectively reactivated EBV in Burkitt lymphoma cells, with CMER sgRNA-5 demonstrating strong reactivation across different cancer cell types. Combining CMER with ganciclovir selectively eliminated EBV-positive cells, showing promise for EBV-associated cancer treatment.
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Affiliation(s)
- Febri Gunawan Sugiokto
- Program in Microbiology and Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Craniofacial Molecular Biology, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Renfeng Li
- Program in Microbiology and Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Cancer Virology Program, Hillman Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Oral and Craniofacial Molecular Biology, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
- Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
- Department of Microbiology and Immunology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
- Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia, USA
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4
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Wu M, Hau PM, Li L, Tsang CM, Yang Y, Taghbalout A, Chung GTY, Hui SY, Tang WC, Jillette N, Zhu JJ, Lee HHY, Kong EL, Chan MSA, Chan JYK, Ma BBY, Chen MR, Lee C, To KF, Cheng AW, Lo KW. Synthetic BZLF1-targeted transcriptional activator for efficient lytic induction therapy against EBV-associated epithelial cancers. Nat Commun 2024; 15:3729. [PMID: 38702330 PMCID: PMC11068728 DOI: 10.1038/s41467-024-48031-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 04/17/2024] [Indexed: 05/06/2024] Open
Abstract
The unique virus-cell interaction in Epstein-Barr virus (EBV)-associated malignancies implies targeting the viral latent-lytic switch is a promising therapeutic strategy. However, the lack of specific and efficient therapeutic agents to induce lytic cycle in these cancers is a major challenge facing clinical implementation. We develop a synthetic transcriptional activator that specifically activates endogenous BZLF1 and efficiently induces lytic reactivation in EBV-positive cancer cells. A lipid nanoparticle encapsulating nucleoside-modified mRNA which encodes a BZLF1-specific transcriptional activator (mTZ3-LNP) is synthesized for EBV-targeted therapy. Compared with conventional chemical inducers, mTZ3-LNP more efficiently activates EBV lytic gene expression in EBV-associated epithelial cancers. Here we show the potency and safety of treatment with mTZ3-LNP to suppress tumor growth in EBV-positive cancer models. The combination of mTZ3-LNP and ganciclovir yields highly selective cytotoxic effects of mRNA-based lytic induction therapy against EBV-positive tumor cells, indicating the potential of mRNA nanomedicine in the treatment of EBV-associated epithelial cancers.
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Affiliation(s)
- Man Wu
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Translational Oncology, Sir YK Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Pok Man Hau
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Linxian Li
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, Shatin, Hong Kong SAR, China
- Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
- Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Hong Kong SAR, China
| | - Chi Man Tsang
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Translational Oncology, Sir YK Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Yike Yang
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, Shatin, Hong Kong SAR, China
- College of Chemistry and Green Catalysis Center, Zhengzhou University, Zhengzhou, China
| | - Aziz Taghbalout
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
| | - Grace Tin-Yun Chung
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Shin Yee Hui
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Wing Chung Tang
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | | | - Jacqueline Jufen Zhu
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, 85281, USA
| | - Horace Hok Yeung Lee
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, Shatin, Hong Kong SAR, China
| | - Ee Ling Kong
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Melissa Sue Ann Chan
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Jason Ying Kuen Chan
- Department of Otorhinolaryngology, Head and Neck Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Brigette Buig Yue Ma
- Department of Clinical Oncology, State Key Laboratory of Translational Oncology, Charlie Lee Precision Immuno-oncology program, Sir Y.K. Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Mei-Ru Chen
- Graduate Institute and Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 100233, Taiwan
| | - Charles Lee
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA
| | - Ka Fai To
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Translational Oncology, Sir YK Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Albert Wu Cheng
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06032, USA.
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, 85281, USA.
- Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, CT, 06030, USA.
- Institute for Systems Genomics, University of Connecticut Health Center, Farmington, CT, 06030, USA.
- The Jackson Laboratory Cancer Center, Bar Harbor, ME, 04609, USA.
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- Key Laboratory of Organ Regeneration and Reconstruction, Chinese Academy of Sciences, Beijing, China.
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
| | - Kwok-Wai Lo
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China.
- State Key Laboratory of Translational Oncology, Sir YK Pao Centre for Cancer, The Chinese University of Hong Kong, Hong Kong SAR, China.
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Sun Y, Shi D, Sun J, Zhang Y, Liu W, Luo B. Regulation mechanism of EBV-encoded EBER1 and LMP2A on YAP1 and the impact of YAP1 on the EBV infection status in EBV-associated gastric carcinoma. Virus Res 2024; 343:199352. [PMID: 38462175 PMCID: PMC10982081 DOI: 10.1016/j.virusres.2024.199352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/07/2024] [Accepted: 03/07/2024] [Indexed: 03/12/2024]
Abstract
This study aims to explore the role and regulatory mechanism of Yes-associated protein 1 (YAP1) in the development of Epstein-Barr virus-associated gastric cancer (EBVaGC). Here we showed that EBV can upregulate the expression and activity of YAP1 protein through its encoded latent products EBV-encoded small RNA 1 (EBER1) and latent membrane protein 2A (LMP2A), enhancing the malignant characteristics of EBVaGC cells. In addition, we also showed that overexpression of YAP1 induced the expression of EBV encoding latent and lytic phase genes and proteins in the epithelial cell line AGS-EBV infected with EBV, and increased the copy number of the EBV genome, while loss of YAP1 expression reduced the aforementioned indicators. Moreover, we found that YAP1 enhanced EBV lytic reactivation induced by two known activators, 12-O-tetradecanoylhorbol-13-acetate (TPA) and sodium butyrate (NaB). These results indicated a bidirectional regulatory mechanism between EBV and YAP1 proteins, providing new experimental evidence for further understanding the regulation of EBV infection patterns and carcinogenic mechanisms in gastric cancer.
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Affiliation(s)
- Yujie Sun
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao 266071, China
| | - Duo Shi
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao 266071, China
| | - Jiting Sun
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao 266071, China
| | - Yan Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao 266071, China; Department of Clinical Laboratory, Zibo Central Hospital, ZiBo 255036, China
| | - Wen Liu
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao 266071, China.
| | - Bing Luo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao 266071, China.
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6
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Kim JY, Min YJ, Lee MH, An YR, Ashktorab H, Smoot DT, Kwon SW, Lee SK. Ceramide promotes lytic reactivation of Epstein-Barr virus in gastric carcinoma. J Virol 2024; 98:e0177623. [PMID: 38197630 PMCID: PMC10878077 DOI: 10.1128/jvi.01776-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 12/11/2023] [Indexed: 01/11/2024] Open
Abstract
Epstein-Barr virus (EBV) has a lifelong latency period after initial infection. Rarely, however, when the EBV immediate early gene BZLF1 is expressed by a specific stimulus, the virus switches to the lytic cycle to produce progeny viruses. We found that EBV infection reduced levels of various ceramide species in gastric cancer cells. As ceramide is a bioactive lipid implicated in the infection of various viruses, we assessed the effect of ceramide on the EBV lytic cycle. Treatment with C6-ceramide (C6-Cer) induced an increase in the endogenous ceramide pool and increased production of the viral product as well as BZLF1 expression. Treatment with the ceramidase inhibitor ceranib-2 induced EBV lytic replication with an increase in the endogenous ceramide pool. The glucosylceramide synthase inhibitor Genz-123346 inhibited C6-Cer-induced lytic replication. C6-Cer induced extracellular signal-regulated kinase 1/2 (ERK1/2) and CREB phosphorylation, c-JUN expression, and accumulation of the autophagosome marker LC3B. Treatment with MEK1/2 inhibitor U0126, siERK1&2, or siCREB suppressed C6-Cer-induced EBV lytic replication and autophagy initiation. In contrast, siJUN transfection had no impact on BZLF1 expression. The use of 3-methyladenine (3-MA), an inhibitor targeting class III phosphoinositide 3-kinases (PI3Ks) to inhibit autophagy initiation, resulted in reduced beclin-1 expression, along with suppressed C6-Cer-induced BZLF1 expression and LC3B accumulation. Chloroquine, an inhibitor of autophagosome-lysosome fusion, increased BZLF1 protein intensity and LC3B accumulation. However, siLC3B transfection had minimal effect on BZLF1 expression. The results suggest the significance of ceramide-related sphingolipid metabolism in controlling EBV latency, highlighting the potential use of drugs targeting sphingolipid metabolism for treating EBV-positive gastric cancer.IMPORTANCEEpstein-Barr virus remains dormant in the host cell but occasionally switches to the lytic cycle when stimulated. However, the exact molecular mechanism of this lytic induction is not well understood. In this study, we demonstrate that Epstein-Barr virus infection leads to a reduction in ceramide levels. Additionally, the restoration of ceramide levels triggers lytic replication of Epstein-Barr virus with increase in phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and CREB. Our study suggests that the Epstein-Barr virus can inhibit lytic replication and remain latent through reduction of host cell ceramide levels. This study reports the regulation of lytic replication by ceramide in Epstein-Barr virus-positive gastric cancer.
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Affiliation(s)
- Jun Yeob Kim
- Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
- Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Young Jin Min
- College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Min-Hyeok Lee
- Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
- Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Yea Rim An
- Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
- Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | | | - Duane T. Smoot
- Department of Medicine, Howard University, Washington, DC, USA
| | - Sung Won Kwon
- College of Pharmacy, Seoul National University, Seoul, South Korea
| | - Suk Kyeong Lee
- Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
- Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
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7
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Maestri D, Napoletani G, Kossenkov A, Preston-Alp S, Caruso LB, Tempera I. The three-dimensional structure of the EBV genome plays a crucial role in regulating viral gene expression in EBVaGC. Nucleic Acids Res 2023; 51:12092-12110. [PMID: 37889078 PMCID: PMC10711448 DOI: 10.1093/nar/gkad936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/04/2023] [Accepted: 10/10/2023] [Indexed: 10/28/2023] Open
Abstract
Epstein-Barr virus (EBV) establishes lifelong asymptomatic infection by replication of its chromatinized episomes with the host genome. EBV exhibits different latency-associated transcriptional repertoires, each with distinct three-dimensional structures. CTCF, Cohesin and PARP1 are involved in maintaining viral latency and establishing episome architecture. Epstein-Barr virus-associated gastric cancer (EBVaGC) represents 1.3-30.9% of all gastric cancers globally. EBV-positive gastric cancers exhibit an intermediate viral transcription profile known as 'Latency II', expressing specific viral genes and noncoding RNAs. In this study, we investigated the impact of PARP1 inhibition on CTCF/Cohesin binding in Type II latency. We observed destabilization of the binding of both factors, leading to a disrupted three-dimensional architecture of the episomes and an altered viral gene expression. Despite sharing the same CTCF binding profile, Type I, II and III latencies exhibit different 3D structures that correlate with variations in viral gene expression. Additionally, our analysis of H3K27ac-enriched interactions revealed differences between Type II latency episomes and a link to cellular transformation through docking of the EBV genome at specific sites of the Human genome, thus promoting oncogene expression. Overall, this work provides insights into the role of PARP1 in maintaining active latency and novel mechanisms of EBV-induced cellular transformation.
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Affiliation(s)
- Davide Maestri
- The Wistar Institute, Philadelphia, PA 19104, USA
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
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8
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Preston-Alp S, Caruso LB, Su C, Keith K, Soldan SS, Maestri D, Madzo J, Kossenkov A, Napoletani G, Gewurz B, Lieberman PM, Tempera I. Decitabine disrupts EBV genomic epiallele DNA methylation patterns around CTCF binding sites to increase chromatin accessibility and lytic transcription in gastric cancer. mBio 2023; 14:e0039623. [PMID: 37606370 PMCID: PMC10653948 DOI: 10.1128/mbio.00396-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 06/30/2023] [Indexed: 08/23/2023] Open
Abstract
IMPORTANCE Epstein-Barr virus (EBV) latency is controlled by epigenetic silencing by DNA methylation [5-methyl cytosine (5mC)], histone modifications, and chromatin looping. However, how they dictate the transcriptional program in EBV-associated gastric cancers remains incompletely understood. EBV-associated gastric cancer displays a 5mC hypermethylated phenotype. A potential treatment for this cancer subtype is the DNA hypomethylating agent, which induces EBV lytic reactivation and targets hypermethylation of the cellular DNA. In this study, we identified a heterogeneous pool of EBV epialleles within two tumor-derived gastric cancer cell lines that are disrupted with a hypomethylating agent. Stochastic DNA methylation patterning at critical regulatory regions may be an underlying mechanism for spontaneous reactivation. Our results highlight the critical role of epigenetic modulation on EBV latency and life cycle, which is maintained through the interaction between 5mC and the host protein CCCTC-binding factor.
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Affiliation(s)
| | | | - Chenhe Su
- The Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Kelsey Keith
- The Coriell Institute for Medical Research, Camden, New Jersey, USA
| | | | | | - Jozef Madzo
- The Coriell Institute for Medical Research, Camden, New Jersey, USA
| | | | | | - Benjamin Gewurz
- Division of Infectious Diseases, Brigham & Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Italo Tempera
- The Wistar Institute, Philadelphia, Pennsylvania, USA
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9
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Xu M, Zhang L, Feng J, Yang S, Wang Y, Wang Y, Chen M, Zhou L, Zhang J, Qin Q. Establishment and characterization of two Epstein-Barr virus-positive gastric cancer cell lines with epitheliotropic M81 strain undergoing distinct viral and altered cellular expression profiles. J Med Virol 2023; 95:e28387. [PMID: 36478267 DOI: 10.1002/jmv.28387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 11/30/2022] [Accepted: 12/03/2022] [Indexed: 12/09/2022]
Abstract
Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) is a distinct subtype of gastric cancer (GC) distinguished by the presence of the EBV genome and limited viral gene expression within malignant epithelial cells. EBV infection is generally thought to be a relatively late event following atrophic gastritis in carcinogenesis, which implies the heterogeneity of EBVaGC. To facilitate the study of the role of EBV in EBVaGC, we established two EBV-positive GC cell lines (AGS-EBV and HGC27-EBV) with an epitheliotropic EBV strain M81 and characterized viral and cellular gene expression profiles in comparison to SNU719, a naturally derived EBV-positive GC cell line. Like SNU719, AGS-EBV and HGC27-EBV stably maintained their EBV genomes and expressed EBV-encoded small RNAs and nuclear antigen EBNA1. Comprehensive analysis of the expression of EBV-encoded miRNAs within the BamHI-A region rightward transcript region, and the transcripts of EBV latent and lytic genes in cell lines, as well as xenografts, reveals that AGS-EBV and HGC27-EBV cells undergo distinct viral expression profiles. A very small fraction of AGS-EBV and SNU719 cells can spontaneously produce infectious progeny virions, while HGC27-EBV does not. AGS-EBV (both M81 and Akata) cells largely mimic SNU719 cells in viral gene expression profiles, and altered cellular functions and pathways perturbed by EBV infection. Phylogenetic analysis of the EBV genome shows both M81 and Akata EBV strains are closely related to clinical EBVaGC isolates. Taken together, these two newly established EBV-positive GC cell lines can serve as models to further investigate the role of EBV in different contexts of gastric carcinogenesis and identify novel therapeutics against EBVaGC.
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Affiliation(s)
- Mingqian Xu
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Liang Zhang
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Jinfu Feng
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Shuaibing Yang
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Yixuan Wang
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Yuyi Wang
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Meiyang Chen
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
| | - Li Zhou
- Department of Gynecologic Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Junjie Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, Hubei, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, Hubei, China
| | - Qingsong Qin
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou, Guangdong, China
- Guangdong Provincial Key Laboratory for Diagnosis and Treatment of Breast Cancer, Shantou University Medical College, Shantou, Guangdong, China
- Center of Pathogen Biology and Immunology, Institute of Basic Medical Research, Shantou University Medical College, Shantou, Guangdong, China
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10
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Epstein-Barr Virus Viral Processivity Factor EA-D Facilitates Virus Lytic Replication by Inducing Poly(ADP-Ribose) Polymerase 1 Degradation. J Virol 2022; 96:e0037122. [PMID: 36286483 PMCID: PMC9645209 DOI: 10.1128/jvi.00371-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PARP1 acts as a negative regulator of lytic replication in EBV. To successfully enter the reactivation cycle, EBV has developed multiple strategies to counteract the host’s repressive mechanisms.
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11
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Du Y, Zhang JY, Gong LP, Feng ZY, Wang D, Pan YH, Sun LP, Wen JY, Chen GF, Liang J, Chen JN, Shao CK. Hypoxia-induced ebv-circLMP2A promotes angiogenesis in EBV-associated gastric carcinoma through the KHSRP/VHL/HIF1α/VEGFA pathway. Cancer Lett 2022; 526:259-272. [PMID: 34863886 DOI: 10.1016/j.canlet.2021.11.031] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 12/11/2022]
Abstract
EBV-encoded circular RNA LMP2A (ebv-circLMP2A) was found to be expressed in EBV-associated gastric carcinoma (EBVaGC) and associated with distant metastasis and poor prognosis. Angiogenesis is a key step in tumor invasion and metastasis and plays a crucial role in tumor progression. However, it is unclear whether and how ebv-circLMP2A is involved in angiogenesis. In this study, we showed that MVD, HIF1α, and VEGFA expression was increased in EBVaGC mouse xenografts with high expression of ebv-circLMP2A. The expression of ebv-circLMP2A was positively correlated with MVD, HIF1α, and VEGFA expression in clinical samples of EBVaGC. Knockdown of ebv-circLMP2A repressed tube formation and migration of HUVECs and decreased VEGFA and HIF1α expression in cancer cells under hypoxia, while ectopic expression of ebv-circLMP2A reversed these effects. Additionally, knockdown of HIF1α blocked the upregulation of ebv-circLMP2A by hypoxia, and ebv-circLMP2A interacted with KHSRP to enhance KHSRP-mediated decay of VHL mRNA, leading to the accumulation of HIF1α under hypoxia. There was a positive feedback loop between HIF1α and ebv-circLMP2A that promotes angiogenesis under hypoxia. ebv-circLMP2A was essential in regulating tumor angiogenesis in EBVaGC and might provide a valuable therapeutic target for EBVaGC.
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Affiliation(s)
- Yu Du
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jing-Yue Zhang
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Li-Ping Gong
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhi-Ying Feng
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Deyu Wang
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yu-Hang Pan
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Li-Ping Sun
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jing-Yun Wen
- Department of Medical Oncology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Gao-Feng Chen
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jing Liang
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jian-Ning Chen
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
| | - Chun-Kui Shao
- Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
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12
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EBNA1 inhibitors have potent and selective antitumor activity in xenograft models of Epstein-Barr virus-associated gastric cancer. Gastric Cancer 2021; 24:1076-1088. [PMID: 33929613 PMCID: PMC8338878 DOI: 10.1007/s10120-021-01193-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/20/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) is the most common EBV-associated cancer and accounts for ~ 10% of all gastric cancers (GC). Epstein-Barr virus nuclear antigen 1 (EBNA1), which is critical for the replication and maintenance of the EBV latent genome, is consistently expressed in all EBVaGC tumors. We previously developed small molecule inhibitors of EBNA1. In this study, we investigated the efficacy and selectivity of an EBNA1 inhibitor in cell-based and animal xenograft models of EBV-positive and EBV-negative gastric carcinoma. METHODS We tested the potency of an EBNA1 inhibitor, VK-1727, in vitro and in xenograft studies, using EBV-positive (SNU719 and YCCEL1) and EBV-negative (AGS and MKN74) GC cell lines. After treatment, we analyzed cell viability, proliferation, and RNA expression of EBV genes by RT-qPCR. RESULTS Treatment with VK-1727 selectively inhibits cell cycle progression and proliferation in vitro. In animal studies, treatment with an EBNA1 inhibitor resulted in a significant dose-dependent decrease in tumor growth in EBVaGC xenograft models, but not in EBV-negative GC xenograft studies. Gene expression analysis revealed that short term treatment in cell culture tended towards viral gene activation, while long-term treatment in animal xenografts showed a significant decrease in viral gene expression. CONCLUSIONS EBNA1 inhibitors are potent and selective inhibitors of cell growth in tissue culture and animal models of EBV-positive GC. Long-term treatment with EBNA1 inhibitors may lead to loss of EBV in mouse xenografts. These results suggest that pharmacological targeting of EBNA1 may be an effective strategy to treat patients with EBVaGC.
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13
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Lee SH, Choi SJ, Choi W, Cho S, Cho M, Kim DS, Kang BW, Kim JG, Lee YM, Cho H, Kang H. Cisplatin Resistance in Epstein-Barr-Virus-Associated Gastric Carcinoma Acquired through ATM Methylation. Cancers (Basel) 2021; 13:cancers13174252. [PMID: 34503060 PMCID: PMC8428228 DOI: 10.3390/cancers13174252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/20/2021] [Accepted: 08/22/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Gastric cancer (GC) is the fifth-leading type of cancer and the third –leading cause of death from cancer. Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is recently accountable for 10% of all the GC worldwide. Platinum drugs such as cisplatin and oxaliplatin are the first-line choice in GC chemotherapy. The widespread use of cisplatin leads to make tumor cells develop single or multiple drug resistance via various mechanisms. DNA hypermethylation on tumor suppressor genes is one of causes leading to drug resistances. 5-Azacytidine (5-AZA) is a chemical analogue of cytidine and inhibits DNA methyltransferase, resulting in DNA hypomethylation. Our main objective was to identify synergistic effect of two important GC drugs whose mechanisms may be in complementary cooperation. We found that cisplatin enhances its anticancer activity with 5-AZA through DNA demethylation in EBVaGC. Identifying this synergistic effect of two important GC drugs can be useful to treat EBVaGC which shows resistance to platinum-based chemotherapy. Abstract Epstein–Barr-virus-associated gastric carcinoma (EBVaGC), first reported in 1992, currently accounts for 10% of all gastric carcinoma worldwide. EBVaGC has unique DNA hypermethylation phenotypes that allow for higher proportions of DNA methylation than any other gastric cancer. CpG islands in the gene promoter region are one of the major regions in which DNA methylation controls gene transcription. Despite cisplatin-based chemotherapy being one of the standard treatment regimens for advanced gastric cancer, including EBVaGC, cisplatin alone or in combination with 5-fluorouracil has been limited by its less potent anticancer activity and the occurrence of cisplatin resistance. Accordingly, the current study evaluated the anticancer activities of a combination of cisplatin and 5-Azacytidine (5-AZA) against EBVaGC. Our findings showed that cisplatin upregulated the DNMT3A gene, whereas shRNA-targeted removal of DNMT3A mRNA contributed to cisplatin-mediated EBV lytic reactivation. Moreover, the removal of DNMT3A mRNA upregulated the ATM gene through DNA demethylation on the ATM promoter. Furthermore, CRISPR/Cas9-targeted removal of the ATM gene resulted in significantly reduced cell susceptibility and EBV lytic reactivation by a combination of cisplatin and DNMT3A inhibitor 5-AZA. Finally, 5-AZA exhibited a synergistic effect with cisplatin in anti-EBV and anti-EBVaGC activities by increasing drug susceptibility and EBV lytic reactivation. The aforementioned results suggest that cisplatin combined with DNA methylation inhibitors could be a novel therapeutic approach for EBVaGC.
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Affiliation(s)
- Sun Hee Lee
- Vessel-Organ Interaction Research Center, VOICE (MRC), Cancer Research Institute, College of Pharmacy, Kyungpook National University, Daegu 41566, Korea; (S.H.L.); (S.J.C.); (S.C.); (M.C.)
| | - Su Jin Choi
- Vessel-Organ Interaction Research Center, VOICE (MRC), Cancer Research Institute, College of Pharmacy, Kyungpook National University, Daegu 41566, Korea; (S.H.L.); (S.J.C.); (S.C.); (M.C.)
| | - Wonhyeok Choi
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women’s University, Seoul 01369, Korea;
| | - Subin Cho
- Vessel-Organ Interaction Research Center, VOICE (MRC), Cancer Research Institute, College of Pharmacy, Kyungpook National University, Daegu 41566, Korea; (S.H.L.); (S.J.C.); (S.C.); (M.C.)
| | - Miyeon Cho
- Vessel-Organ Interaction Research Center, VOICE (MRC), Cancer Research Institute, College of Pharmacy, Kyungpook National University, Daegu 41566, Korea; (S.H.L.); (S.J.C.); (S.C.); (M.C.)
| | - Dong Sun Kim
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu 41944, Korea;
| | - Byung Woog Kang
- Department of Oncology/Hematology, Cancer Research Institute, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu 41405, Korea; (B.W.K.); (J.G.K.)
| | - Jong Gwang Kim
- Department of Oncology/Hematology, Cancer Research Institute, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu 41405, Korea; (B.W.K.); (J.G.K.)
| | - You Mie Lee
- Vessel-Organ Interaction Research Center, VOICE (MRC), Department of Molecular Pathophysiology, College of Pharmacy, Kyungpook National University, Daegu 41566, Korea;
| | - Hyosun Cho
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women’s University, Seoul 01369, Korea;
- Correspondence: (H.C.); (H.K.); Tel.: +82-02-901-8678 (H.C.); +82-053-950-8569 (H.K.); Fax: +82-02-901-8386 (H.C.); +82-053-950-8557 (H.K.)
| | - Hyojeung Kang
- Vessel-Organ Interaction Research Center, VOICE (MRC), Cancer Research Institute, College of Pharmacy, Kyungpook National University, Daegu 41566, Korea; (S.H.L.); (S.J.C.); (S.C.); (M.C.)
- Correspondence: (H.C.); (H.K.); Tel.: +82-02-901-8678 (H.C.); +82-053-950-8569 (H.K.); Fax: +82-02-901-8386 (H.C.); +82-053-950-8557 (H.K.)
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14
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Padmanabhan N, Kyon HK, Boot A, Lim K, Srivastava S, Chen S, Wu Z, Lee HO, Mukundan VT, Chan C, Chan YK, Xuewen O, Pitt JJ, Isa ZFA, Xing M, Lee MH, Tan ALK, Ting SHW, Luftig MA, Kappei D, Kruger WD, Bian J, Ho YS, Teh M, Rozen SG, Tan P. Highly recurrent CBS epimutations in gastric cancer CpG island methylator phenotypes and inflammation. Genome Biol 2021; 22:167. [PMID: 34074348 PMCID: PMC8170989 DOI: 10.1186/s13059-021-02375-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 05/06/2021] [Indexed: 02/06/2023] Open
Abstract
Background CIMP (CpG island methylator phenotype) is an epigenetic molecular subtype, observed in multiple malignancies and associated with the epigenetic silencing of tumor suppressors. Currently, for most cancers including gastric cancer (GC), mechanisms underlying CIMP remain poorly understood. We sought to discover molecular contributors to CIMP in GC, by performing global DNA methylation, gene expression, and proteomics profiling across 14 gastric cell lines, followed by similar integrative analysis in 50 GC cell lines and 467 primary GCs. Results We identify the cystathionine beta-synthase enzyme (CBS) as a highly recurrent target of epigenetic silencing in CIMP GC. Likewise, we show that CBS epimutations are significantly associated with CIMP in various other cancers, occurring even in premalignant gastroesophageal conditions and longitudinally linked to clinical persistence. Of note, CRISPR deletion of CBS in normal gastric epithelial cells induces widespread DNA methylation changes that overlap with primary GC CIMP patterns. Reflecting its metabolic role as a gatekeeper interlinking the methionine and homocysteine cycles, CBS loss in vitro also causes reductions in the anti-inflammatory gasotransmitter hydrogen sulfide (H2S), with concomitant increase in NF-κB activity. In a murine genetic model of CBS deficiency, preliminary data indicate upregulated immune-mediated transcriptional signatures in the stomach. Conclusions Our results implicate CBS as a bi-faceted modifier of aberrant DNA methylation and inflammation in GC and highlights H2S donors as a potential new therapy for CBS-silenced lesions. Supplementary Information The online version contains supplementary material available at 10.1186/s13059-021-02375-2.
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Affiliation(s)
- Nisha Padmanabhan
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Huang Kie Kyon
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Arnoud Boot
- Centre for Computational Biology, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Kevin Lim
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Supriya Srivastava
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228, Singapore
| | - Shuwen Chen
- Bioprocessing Technology Institute, A*STAR, 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Zhiyuan Wu
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore
| | - Hyung-Ok Lee
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Vineeth T Mukundan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | - Charlene Chan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | - Yarn Kit Chan
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Ong Xuewen
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Jason J Pitt
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | - Zul Fazreen Adam Isa
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Manjie Xing
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Ming Hui Lee
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Angie Lay Keng Tan
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Shamaine Ho Wei Ting
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore
| | - Micah A Luftig
- Department of Molecular Genetics and Microbiology, Duke Centre for Virology, Duke University School of Medicine, Durham, NC, USA
| | - Dennis Kappei
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117596, Singapore
| | - Warren D Kruger
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Jinsong Bian
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore.,National University of Singapore (Suzhou) Research Institute, Suzhou, 215123, China
| | - Ying Swan Ho
- Bioprocessing Technology Institute, A*STAR, 20 Biopolis Way, #06-01 Centros, Singapore, 138668, Singapore
| | - Ming Teh
- Department of Pathology, National University of Singapore, Singapore, 119228, Singapore
| | - Steve George Rozen
- Centre for Computational Biology, Duke-NUS Medical School, Singapore, 169857, Singapore
| | - Patrick Tan
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 8, College road, Singapore, 169857, Singapore. .,Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore. .,Genome Institute of Singapore, Singapore, 138672, Singapore. .,SingHealth/Duke-NUS Institute of Precision Medicine, National Heart Centre Singapore, Singapore, 169856, Singapore. .,Singapore Gastric Cancer Consortium, Singapore, 119074, Singapore. .,Department of Physiology, National University of Singapore, Singapore, 117593, Singapore.
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15
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Scott TA, Morris KV. Designer nucleases to treat malignant cancers driven by viral oncogenes. Virol J 2021; 18:18. [PMID: 33441159 PMCID: PMC7805041 DOI: 10.1186/s12985-021-01488-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/02/2021] [Indexed: 11/22/2022] Open
Abstract
Viral oncogenic transformation of healthy cells into a malignant state is a well-established phenomenon but took decades from the discovery of tumor-associated viruses to their accepted and established roles in oncogenesis. Viruses cause ~ 15% of know cancers and represents a significant global health burden. Beyond simply causing cellular transformation into a malignant form, a number of these cancers are augmented by a subset of viral factors that significantly enhance the tumor phenotype and, in some cases, are locked in a state of oncogenic addiction, and substantial research has elucidated the mechanisms in these cancers providing a rationale for targeted inactivation of the viral components as a treatment strategy. In many of these virus-associated cancers, the prognosis remains extremely poor, and novel drug approaches are urgently needed. Unlike non-specific small-molecule drug screens or the broad-acting toxic effects of chemo- and radiation therapy, the age of designer nucleases permits a rational approach to inactivating disease-causing targets, allowing for permanent inactivation of viral elements to inhibit tumorigenesis with growing evidence to support their efficacy in this role. Although many challenges remain for the clinical application of designer nucleases towards viral oncogenes; the uniqueness and clear molecular mechanism of these targets, combined with the distinct advantages of specific and permanent inactivation by nucleases, argues for their development as next-generation treatments for this aggressive group of cancers.
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Affiliation(s)
- Tristan A Scott
- Center for Gene Therapy, City of Hope, Beckman Research Institute and Hematological Malignancy and Stem Cell Transplantation Institute at the City of Hope, 1500 E. Duarte Rd, Duarte, CA, 91010, USA.
| | - Kevin V Morris
- Center for Gene Therapy, City of Hope, Beckman Research Institute and Hematological Malignancy and Stem Cell Transplantation Institute at the City of Hope, 1500 E. Duarte Rd, Duarte, CA, 91010, USA
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16
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Yajima M, Kakuta R, Saito Y, Kitaya S, Toyoda A, Ikuta K, Yasuda J, Ohta N, Kanda T. A global phylogenetic analysis of Japanese tonsil-derived Epstein-Barr virus strains using viral whole-genome cloning and long-read sequencing. J Gen Virol 2021; 102. [PMID: 33433312 DOI: 10.1099/jgv.0.001549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Epstein-Barr virus (EBV) establishes lifelong latent infection in the majority of healthy individuals, while it is a causative agent for various diseases, including some malignancies. Recent high-throughput sequencing results indicate that there are substantial levels of viral genome heterogeneity among different EBV strains. However, the extent of EBV strain variation among asymptomatically infected individuals remains elusive. Here, we present a streamlined experimental strategy to clone and sequence EBV genomes derived from human tonsillar tissues, which are the reservoirs of asymptomatic EBV infection. Complete EBV genome sequences, including those of repetitive regions, were determined for seven tonsil-derived EBV strains. Phylogenetic analyses based on the whole viral genome sequences of worldwide non-tumour-derived EBV strains revealed that Asian EBV strains could be divided into several distinct subgroups. EBV strains derived from nasopharyngeal carcinoma-endemic areas constitute different subgroups from a subgroup of EBV strains from non-endemic areas, including Japan. The results could be consistent with biased regional distribution of EBV-associated diseases depending on the different EBV strains colonizing different regions in Asian countries.
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Affiliation(s)
- Misako Yajima
- Division of Microbiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Risako Kakuta
- Present address: Department of Otolaryngology, Head and Neck Surgery, Tohoku University School of Medicine, Sendai, Miyagi, Japan.,Division of Otolaryngology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Yutaro Saito
- Present address: Department of Otolaryngology, Head and Neck Surgery, Tohoku University School of Medicine, Sendai, Miyagi, Japan.,Division of Otolaryngology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Shiori Kitaya
- Present address: Department of Otolaryngology, Head and Neck Surgery, Tohoku University School of Medicine, Sendai, Miyagi, Japan.,Division of Otolaryngology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Kazufumi Ikuta
- Division of Microbiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Jun Yasuda
- Present address: Division of Molecular and Cellular Oncology, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan.,Division of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Miyagi, Japan
| | - Nobuo Ohta
- Division of Otolaryngology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
| | - Teru Kanda
- Division of Microbiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, Japan
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17
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Liu W, Luo B. The impact of EBV on the epigenetics of gastric carcinoma. Future Virol 2020. [DOI: 10.2217/fvl-2019-0148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
EBV is an important human tumor virus and is closely related to the occurrence of a variety of tumors, involving 10% of gastric cancer. In EBV-associated gastric carcinoma (EBVaGC), EBV expresses restrict viral genes including EBV nuclear antigen 1, EBV encoded small RNAs, Bam HI-A rightward transcripts, latent membrane protein 2A and miRNAs. The role of EBV in gastric carcinogenesis has received increasing attention and is considered to be another pathogenic factor in addition to Helicobacter pylori. A typical characteristic of EBVaGC is the extensive methylation of viral and host genome. Combined with other epigenetic mechanisms, EBV infection acts as an epigenetic driver of EBVaGC oncogenesis. In this review we discuss recent findings of EBV effect on host epigenetic alterations in EBVaGC and its role in oncogenic process.
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Affiliation(s)
- Wen Liu
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, PR China
| | - Bing Luo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, PR China
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18
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Yoon JH, Min K, Lee SK. Epstein-Barr Virus miR-BART17-5p Promotes Migration and Anchorage-Independent Growth by Targeting Kruppel-Like Factor 2 in Gastric Cancer. Microorganisms 2020; 8:microorganisms8020258. [PMID: 32075248 PMCID: PMC7074886 DOI: 10.3390/microorganisms8020258] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 12/24/2022] Open
Abstract
Epstein-Barr virus (EBV) infects more than 90% of the global population and is associated with a variety of tumors including nasopharyngeal carcinoma, Hodgkin lymphoma, natural killer/T lymphoma, and gastric carcinoma. In EBV-associated gastric cancer (EBVaGC), highly expressed EBV BamHI A rightward transcripts (BART) miRNAs may contribute to tumorigenesis with limited viral antigens. Despite previous studies on the targets of BART miRNAs, the functions of all 44 BART miRNAs have not been fully clarified. Here, we used RNA sequencing data from the Cancer Genome Atlas to find genes with decreased expression in EBVaGC. Furthermore, we used AGS cells infected with EBV to determine whether expression was reduced by BART miRNA. We showed that the expression of Kruppel-like factor 2 (KLF2) is lower in AGS-EBV cells than in the AGS control. Using bioinformatics analysis, four BART miRNAs were selected to check whether they suppress KLF2 expression. We found that only miR-BART17-5p directly down-regulated KLF2 and promoted gastric carcinoma cell migration and anchorage-independent growth. Our data suggest that KLF2 functions as a tumor suppressor in EBVaGC and that miR-BART17-5p may be a valuable target for effective EBVaGC treatment.
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Affiliation(s)
| | | | - Suk Kyeong Lee
- Correspondence: ; Tel.: +82-2-2258-7480; Fax: +82-504-201-2396
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19
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A single nucleotide polymorphism in the BART promoter region of Epstein-Barr virus isolated from nasopharyngeal cancer cells. Biochem Biophys Res Commun 2019; 520:373-378. [DOI: 10.1016/j.bbrc.2019.10.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 10/02/2019] [Indexed: 12/21/2022]
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20
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Cone AS, York SB, Meckes DG. Extracellular Vesicles in Epstein-Barr Virus Pathogenesis. CURRENT CLINICAL MICROBIOLOGY REPORTS 2019; 6:121-131. [PMID: 32051811 DOI: 10.1007/s40588-019-00123-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Purpose of review Epstein-Barr virus (EBV) is a known determinant for numerous malignancies and may contribute to autoimmune diseases. The underlining mechanisms behind EBV pathologies is not completely understood. Recently, extracellular vesicles (EVs) released from infected cells have been found to produce profound effects on cellular microenvironments. Therefore, in this review we sought to critically evaluate the roles of EVs in EBV pathogenesis and assess their potential therapeutic and diagnostic utility. Recent findings EBV-altered EVs are capable of activating signaling cascades and phenotypic changes in recipient cells through the transfer of viral proteins and RNAs. Moreover, several EV-associated microRNAs have encouraging prognostic or diagnostic potential in EBV-associated cancers. Summary Current evidence suggests that EBV-modified EVs affect viral pathogenesis and cancer progression. However, further research is needed to investigate the direct role of both viral and host products on recipient cells and the mechanisms driving viral protein and RNA EV packaging and content modification.
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Affiliation(s)
- Allaura S Cone
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA
| | - Sara B York
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA
| | - David G Meckes
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA
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21
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Sasaki S, Nishikawa J, Sakai K, Iizasa H, Yoshiyama H, Yanagihara M, Shuto T, Shimokuri K, Kanda T, Suehiro Y, Yamasaki T, Sakaida I. EBV-associated gastric cancer evades T-cell immunity by PD-1/PD-L1 interactions. Gastric Cancer 2019; 22:486-496. [PMID: 30264329 DOI: 10.1007/s10120-018-0880-4] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 09/18/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Epstein-Barr virus (EBV) is an oncogenic human herpesvirus involved in the development of around 10% of gastric cancers. The overexpression of PD-L1 is one of the features of EBV-associated gastric cancer (EBVaGC); however, the function of PD-L1 has not been studied in EBVaGC. METHODS We used three EBVaGC cell lines, SNU719 cells, NCC24 cells, and YCCEL1 cells, to evaluate the PD-L1 expression and function in EBVaGC. Jurkat T-lymphocytes expressing PD-1 were co-cultured with NCC24 and YCCEL1 cells and the cell cycles were analyzed. To study the regulatory mechanism for PD-L1 expression, the 3'UTR of PD-L1 was sequenced, and the effect of inhibitors of the IFN-γ signaling pathway was evaluated. RESULTS All of the EBVaGC cell lines expressed PD-L1, and its expression was further enhanced by stimulation with IFN-γ. In Jurkat T-cells co-cultured with IFN-γ-stimulated NCC24 and YCCEL1 cells, the number of cells in the G0/G1 phase was significantly increased. This G0/G1 arrest was partially released by administration of anti-PD-L1 antibody. We found SNPs in PD-L1 3'UTR nucleotide sequences that were located at seed regions for microRNAs. Treatment of EBVaGC cell lines with JAK2-inhibitor, PI3K-inhibitor, and mTOR inhibitor reduced the level of PD-L1 expression to the same level as cells without IFN-γ stimulation. CONCLUSIONS EBVaGC cells expressing high levels of PD-L1 suppress T-cell proliferation, and the IFN-γ signaling pathway is involved in the expression of PD-L1.
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Affiliation(s)
- Sho Sasaki
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Jun Nishikawa
- Department of Laboratory Science, Yamaguchi University Graduate School of Medicine, Minamikogushi 1-1-1, Ube, Yamaguchi, 755-8505, Japan.
| | - Kohei Sakai
- Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Hisashi Iizasa
- Department of Microbiology, Shimane University Faculty of Medicine, Shimane, Japan
| | - Hironori Yoshiyama
- Department of Microbiology, Shimane University Faculty of Medicine, Shimane, Japan
| | - Masashi Yanagihara
- Department of Laboratory Science, Yamaguchi University Graduate School of Medicine, Minamikogushi 1-1-1, Ube, Yamaguchi, 755-8505, Japan
| | - Takuya Shuto
- Department of Laboratory Science, Yamaguchi University Graduate School of Medicine, Minamikogushi 1-1-1, Ube, Yamaguchi, 755-8505, Japan
| | - Kanami Shimokuri
- Department of Laboratory Science, Yamaguchi University Graduate School of Medicine, Minamikogushi 1-1-1, Ube, Yamaguchi, 755-8505, Japan
| | - Teru Kanda
- Division of Microbiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Yutaka Suehiro
- Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Takahiro Yamasaki
- Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Ube, Japan
| | - Isao Sakaida
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Ube, Japan
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22
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Efficient Epstein-Barr Virus Progeny Production Mediated by Cancer-Derived LMP1 and Virally-Encoded microRNAs. Microorganisms 2019; 7:microorganisms7050119. [PMID: 31052238 PMCID: PMC6560388 DOI: 10.3390/microorganisms7050119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/25/2019] [Accepted: 04/28/2019] [Indexed: 12/22/2022] Open
Abstract
Epstein-Barr virus (EBV) genomes, particularly their latent genes, are heterogeneous among strains. The heterogeneity of EBV-encoded latent membrane protein 1 (LMP1) raises the question of whether there are functional differences between LMP1 expressed by cancer-associated EBV and that by non-cancerous strains. Here, we used bacterial artificial chromosome (BAC)-cloned EBV genomes retaining all virally encoded microRNA (miRNA) genes to investigate the functions of cancer-derived LMP1 in the context of the EBV genome. HEK293 cells were stably transfected with EBV-BAC clone DNAs encoding either nasopharyngeal carcinoma (NPC)-derived CAO-LMP1 (LMP1CAO) or LMP1 from a prototype B95-8 strain of EBV (LMP1B95-8). When an EBV-BAC clone DNA encoding LMP1CAO was stably transfected into HEK293 cells, it generated many more stable transformants than the control clone encoding LMP1B95-8. Furthermore, stably transfected HEK293 cells exhibited highly efficient production of progeny virus. Importantly, deletion of the clustered viral miRNA genes compromised the ability to produce progeny viruses. These results indicate that cancer-derived LMP1 and viral miRNAs together are necessary for efficient production of progeny virus, and that the resulting increase in efficiency contributes to EBV-mediated epithelial carcinogenesis.
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23
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Lee HM, Okuda KS, González FE, Patel V. Current Perspectives on Nasopharyngeal Carcinoma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1164:11-34. [PMID: 31576537 DOI: 10.1007/978-3-030-22254-3_2] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Of the ~129,079 new cases of nasopharyngeal carcinoma (NPC) and 72,987 associated deaths estimated for 2018, the majority will be geographically localized to South East Asia, and likely to show an upward trend annually. It is thought that disparities in dietary habits, lifestyle, and exposures to harmful environmental factors are likely the root cause of NPC incidence rates to differ geographically. Genetic differences due to ethnicity and the Epstein Barr virus (EBV) are likely contributing factors. Pertinently, NPC is associated with poor prognosis which is largely attributed to lack of awareness of the salient symptoms of NPC. These include nose hemorrhage and headaches and coupled with detection and the limited therapeutic options. Treatment options include radiotherapy or chemotherapy or combination of both. Surgical excision is generally the last option considered for advanced and metastatic disease, given the close proximity of nasopharynx to brain stem cell area, major blood vessels, and nerves. To improve outcome of NPC patients, novel cellular and in vivo systems are needed to allow an understanding of the underling molecular events causal for NPC pathogenesis and for identifying novel therapeutic targets and effective therapies. While challenges and gaps in current NPC research are noted, some advances in targeted therapies and immunotherapies targeting EBV NPCs are discussed in this chapter, which may offer improvements in outcome of NPC patients.
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Affiliation(s)
- Hui Mei Lee
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia
| | - Kazuhida Shaun Okuda
- Division of Genomics of Development and Disease, Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Fermín E González
- Laboratory of Experimental Immunology and Cancer, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Vyomesh Patel
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia.
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24
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Abstract
Epstein-Barr virus (EBV) is one of the most widespread human pathogens. EBV infection is usually asymptomatic, and it establishes life-long latent infection. EBV latent infection sometimes causes various tumorigenic diseases, such as EBV-related lymphoproliferative diseases, Burkitt lymphomas, Hodgkin lymphomas, NK/T-cell lymphomas, and epithelial carcinomas. EBV-encoded latent genes are set of viral genes that are expressed in latently infected cells. They include virally encoded proteins, noncoding RNAs, and microRNAs. Different latent gene expression patterns are noticed in different types of EBV-infected cells. Viral latent gene products contribute to EBV-mediated B cell transformation and likely contribute to lymphomagenesis and epithelial carcinogenesis as well. Many biological functions of viral latent gene products have been reported, making difficult to understand a whole view of EBV latency. In this review, we will focus on latent gene functions that have been verified by genetic experiments using EBV mutants. We will also summarize how viral latent genes contribute to EBV-mediated B cell transformation, Burkitt lymphomagenesis, and epithelial carcinogenesis.
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25
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A Comprehensive Human Gastric Cancer Organoid Biobank Captures Tumor Subtype Heterogeneity and Enables Therapeutic Screening. Cell Stem Cell 2018; 23:882-897.e11. [PMID: 30344100 DOI: 10.1016/j.stem.2018.09.016] [Citation(s) in RCA: 475] [Impact Index Per Article: 67.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 09/20/2018] [Accepted: 09/27/2018] [Indexed: 12/12/2022]
Abstract
Gastric cancer displays marked molecular heterogeneity with aggressive behavior and treatment resistance. Therefore, good in vitro models that encompass unique subtypes are urgently needed for precision medicine development. Here, we have established a primary gastric cancer organoid (GCO) biobank that comprises normal, dysplastic, cancer, and lymph node metastases (n = 63) from 34 patients, including detailed whole-exome and transcriptome analysis. The cohort encompasses most known molecular subtypes (including EBV, MSI, intestinal/CIN, and diffuse/GS, with CLDN18-ARHGAP6 or CTNND1-ARHGAP26 fusions or RHOA mutations), capturing regional heterogeneity and subclonal architecture, while their morphology, transcriptome, and genomic profiles remain closely similar to in vivo tumors, even after long-term culture. Large-scale drug screening revealed sensitivity to unexpected drugs that were recently approved or in clinical trials, including Napabucasin, Abemaciclib, and the ATR inhibitor VE-822. Overall, this new GCO biobank, with linked genomic data, provides a useful resource for studying both cancer cell biology and precision cancer therapy.
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26
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Chen JN, Zhou L, Qiu XM, Yang RH, Liang J, Pan YH, Li HF, Peng GR, Shao CK. Determination and genome-wide analysis of Epstein-Barr virus (EBV) sequences in EBV-associated gastric carcinoma from Guangdong, an endemic area of nasopharyngeal carcinoma. J Med Microbiol 2018; 67:1614-1627. [PMID: 30239329 DOI: 10.1099/jmm.0.000839] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
About 10 % of gastric carcinoma worldwide is associated with EBV, which is defined as EBV-associated gastric carcinoma (EBVaGC). To date, EBV sequence data from EBVaGC in Guangdong, China, an endemic area of nasopharyngeal carcinoma (NPC), are not available. In the present study, two EBV genomes from EBVaGC specimens from Guangdong (designated as GDGC1 and GDGC2) were determined by next-generation sequencing, de novo assembly and joining of contigs by Sanger sequencing. In addition, we sequenced EBV from two Korean EBVaGC cell lines, YCCEL1 and SNU-719. Genomic diversity, including single nucleotide polymorphisms (SNPs) and insertions and deletions (indels), phylogenetic analysis and rates of protein evolution, was performed using bioinformatics software. The four gastric carcinoma-derived EBV (GC-EBV) were all type I. Compared with the reference EBV genome, a total of 1815 SNPs (146 indels), 1519 SNPs (106 indels), 1812 SNPs (126 indels) and 1484 SNPs (106 indels) were found in GDGC1, GDGC2, YCCEL1 and SNU-719, respectively. These variations were distributed across the entire genome, especially in latent genes. In contrast, the sequences of promoters and non-coding RNAs were strictly conserved. Phylogenetic analyses suggested the presence of at least two parental lineages of EBV among the GC-EBV genomes. Rates of protein evolution analyses showed that lytic genes were under purifying selection; in contrast, latency genes were under positive selection. In conclusion, this study determined the EBV genomes in EBVaGC from Guangdong and performed a detailed genome-wide analysis of GC-EBV, which would be helpful for further understanding of the relationship between EBV genomic variation and EBVaGC carcinogenesis.
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Affiliation(s)
- Jian-Ning Chen
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
| | - Lu Zhou
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
| | - Xin-Min Qiu
- 2Genetic Testing Lab, Guangdong Provincial Hospital of Chinese Medicine, No. 111 Dade Road, Guangzhou 510120, PR China.,3DRIGEN Co. Ltd., No.121-122 Chuangye Yuan, Shenzhen 518100, PR China
| | - Ri-Hong Yang
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
| | - Jing Liang
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
| | - Yu-Hang Pan
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
| | - Hai-Feng Li
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
| | - Guo-Rong Peng
- 3DRIGEN Co. Ltd., No.121-122 Chuangye Yuan, Shenzhen 518100, PR China
| | - Chun-Kui Shao
- 1Department of Pathology, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Guangzhou 510630, PR China
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27
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Sun L, Meckes DG. Methodological Approaches to Study Extracellular Vesicle miRNAs in Epstein⁻Barr Virus-Associated Cancers. Int J Mol Sci 2018; 19:ijms19092810. [PMID: 30231493 PMCID: PMC6164614 DOI: 10.3390/ijms19092810] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 02/07/2023] Open
Abstract
Epstein Barr-virus (EBV) was the first virus identified to be associated with human cancer in 1964 and is found ubiquitously throughout the world's population. It is now established that EBV contributes to the development and progression of multiple human cancers of both lymphoid and epithelial cell origins. EBV encoded miRNAs play an important role in tumor proliferation, angiogenesis, immune escape, tissue invasion, and metastasis. Recently, EBV miRNAs have been found to be released from infected cancer cells in extracellular vesicles (EVs) and regulate gene expression in neighboring uninfected cells present in the tumor microenvironment and possibly at distal sites. As EVs are abundant in many biological fluids, the viral and cellular miRNAs present within EBV-modified EVs may serve as noninvasion markers for cancer diagnosis and prognosis. In this review, we discuss recent advances in EV isolation and miRNA detection, and provide a complete workflow for EV purification from plasma and deep-sequencing for biomarker discovery.
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Affiliation(s)
- Li Sun
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA.
| | - David G Meckes
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA.
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28
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Phylogenetic comparison of Epstein-Barr virus genomes. J Microbiol 2018; 56:525-533. [PMID: 29948828 DOI: 10.1007/s12275-018-8039-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 02/22/2018] [Accepted: 02/22/2018] [Indexed: 01/06/2023]
Abstract
Technologies used for genome analysis and whole genome sequencing are useful for us to understand genomic characterization and divergence. The Epstein-Barr virus (EBV) is an oncogenic virus that causes diverse diseases such as Burkitt's lymphoma (BL), nasopharyngeal carcinoma (NPC), Hodgkin's lymphoma (HL), and gastric carcinoma (GC). EBV genomes found in these diseases can be classified either by phases of EBV latency (type-I, -II, and -III latency) or types of EBNA2 sequence difference (type-I EBV, type-II EBV or EBV-1, EBV-2). EBV from EBV-transformed lymphoblastoid cell line (LCL) establishes type-III latency, EBV from NPC establishes type-II latency, and EBV from GC establishes type-I latency. However, other important factors play key roles in classifying numerous EBV strains because EBV genomes are highly diverse and not phylogenetically related to types of EBV-associated diseases. Herein, we first reviewed previous studies to describe molecular characteristics of EBV genomes. Then, using comparative and phylogenetic analyses, we phylogenetically analyzed molecular variations of EBV genomes and proteins. The review of previous studies and our phylogenetic analysis showed that EBV genomes and proteins were highly diverse regardless of types of EBV-associated diseases. Other factors should be considered in determining EBV taxonomy. This review will be helpful to understand complicated phylogenetic relationships of EBV genomes.
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29
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Polakovicova I, Jerez S, Wichmann IA, Sandoval-Bórquez A, Carrasco-Véliz N, Corvalán AH. Role of microRNAs and Exosomes in Helicobacter pylori and Epstein-Barr Virus Associated Gastric Cancers. Front Microbiol 2018; 9:636. [PMID: 29675003 PMCID: PMC5895734 DOI: 10.3389/fmicb.2018.00636] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 03/19/2018] [Indexed: 12/17/2022] Open
Abstract
Emerging evidence suggests that chronic inflammation caused by pathogen infection is connected to the development of various types of cancer. It is estimated that up to 20% of all cancer deaths is linked to infections and inflammation. In gastric cancer, such triggers can be infection of the gastric epithelium by either Helicobacter pylori (H. pylori), a bacterium present in half of the world population; or by Epstein-Barr virus (EBV), a double-stranded DNA virus which has recently been associated with gastric cancer. Both agents can establish lifelong inflammation by evolving to escape immune surveillance and, under certain conditions, contribute to the development of gastric cancer. Non-coding RNAs, mainly microRNAs (miRNAs), influence the host innate and adaptive immune responses, though long non-coding RNAs and viral miRNAs also alter these processes. Reports suggest that chronic infection results in altered expression of host miRNAs. In turn, dysregulated miRNAs modulate the host inflammatory immune response, favoring bacterial survival and persistence within the gastric mucosa. Given the established roles of miRNAs in tumorigenesis and innate immunity, they may serve as an important link between H. pylori- and EBV-associated inflammation and carcinogenesis. Example of this is up-regulation of miR-155 in H. pylori and EBV infection. The tumor environment contains a variety of cells that need to communicate with each other. Extracellular vesicles, especially exosomes, allow these cells to deliver certain type of information to other cells promoting cancer growth and metastasis. Exosomes have been shown to deliver not only various types of genetic information, mainly miRNAs, but also cytotoxin-associated gene A (CagA), a major H. pylori virulence factor. In addition, a growing body of evidence demonstrates that exosomes contain genetic material of viruses and viral miRNAs and proteins such as EBV latent membrane protein 1 (LMP1) which are delivered into recipient cells. In this review, we focus on the dysregulated H. pylori- and EBV-associated miRNAs while trying to unveil possible causal mechanisms. Moreover, we discuss the role of exosomes as vehicles for miRNA delivery in H. pylori- and EBV-related carcinogenesis.
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Affiliation(s)
- Iva Polakovicova
- Advanced Center for Chronic Diseases, Pontificia Universidad Católica de Chile, Santiago, Chile.,UC Center for Investigational Oncology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Hematology-Oncology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sofia Jerez
- Department of Hematology-Oncology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ignacio A Wichmann
- Advanced Center for Chronic Diseases, Pontificia Universidad Católica de Chile, Santiago, Chile.,UC Center for Investigational Oncology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Hematology-Oncology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | - Nicolás Carrasco-Véliz
- Advanced Center for Chronic Diseases, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alejandro H Corvalán
- Advanced Center for Chronic Diseases, Pontificia Universidad Católica de Chile, Santiago, Chile.,UC Center for Investigational Oncology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Hematology-Oncology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
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30
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Kim HJ, Kang SK, Kwon WS, Kim TS, Jeong I, Jeung HC, Kragh M, Horak ID, Chung HC, Rha SY. Forty-nine gastric cancer cell lines with integrative genomic profiling for development of c-MET inhibitor. Int J Cancer 2018; 143:151-159. [PMID: 29435981 DOI: 10.1002/ijc.31304] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 01/15/2018] [Accepted: 01/30/2018] [Indexed: 12/24/2022]
Abstract
Receptor tyrosine kinase MET (c-MET) has received considerable attention as a potential target for gastric cancer (GC) therapy and a number of c-MET inhibitors have been developed. For successful drug development, proper preclinical studies especially using patient derived cancer cell lines are very important. We profiled MET and MET-related characteristics in 49 GC cell lines to utilize them as models in preclinical studies of GC. Forty-nine cell lines were analyzed for genetic, biological, and molecular status to characterize MET and MET-related molecules. Four c-MET inhibitors were tested to elucidate the dependency on MET pathway in the 49 GC cell lines. Six of 49 cell lines were MET amplified with overexpression of c-MET and p-MET. The variants of MET were not associated with c-MET expression or amplification. Hs746T showed an exon 14 deletion in conjunction with MET amplification. The cell lines were divided into 6 MET amplified, 2 c-MET overexpressed, 2 hepatocyte growth factor (HGF) overexpressed, and 39 MET-negative subgroups. Except tivantinib, the c-MET inhibitors showed higher inhibition (%) in MET amplified than in MET nonamplified cell lines that MET amplified cell lines showed MET pathway dependency. However, the c-MET overexpressed and HGF overexpressed cell lines showed moderate dependency on MET pathway. Well-characterized cell lines are very important in studying drug development. Our 49 GC cell lines had various characteristics of MET and MET-related molecules and MET pathway dependency. These provide a promising platform for development of various RTK inhibitors including c-MET inhibitors.
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Affiliation(s)
- Hyun Jeong Kim
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sun Kyoung Kang
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Woo Sun Kwon
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Tae Soo Kim
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Inhye Jeong
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hei-Cheul Jeung
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea.,Division of Medical Oncology, Department of Internal Medicine, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
| | | | | | - Hyun Cheol Chung
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea.,Division of Medical Oncology, Department of Internal Medicine, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sun Young Rha
- Songdang Institute for Cancer Research, Yonsei University College of Medicine, Seoul, Republic of Korea.,Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea.,Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea.,Division of Medical Oncology, Department of Internal Medicine, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
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31
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Tsai MH, Lin X, Shumilov A, Bernhardt K, Feederle R, Poirey R, Kopp-Schneider A, Pereira B, Almeida R, Delecluse HJ. The biological properties of different Epstein-Barr virus strains explain their association with various types of cancers. Oncotarget 2018; 8:10238-10254. [PMID: 28052012 PMCID: PMC5354655 DOI: 10.18632/oncotarget.14380] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 12/15/2016] [Indexed: 12/27/2022] Open
Abstract
The Epstein-Barr virus (EBV) is etiologically associated with the development of multiple types of tumors, but it is unclear whether this diversity is due to infection with different EBV strains. We report a comparative characterization of SNU719, GP202, and YCCEL1, three EBV strains that were isolated from gastric carcinomas, M81, a virus isolated in a nasopharyngeal carcinoma and several well-characterized laboratory type A strains. We found that B95-8, Akata and GP202 induced cell growth more efficiently than YCCEL1, SNU719 and M81 and this correlated positively with the expression levels of the viral BHRF1 miRNAs. In infected B cells, all strains except Akata and B95-8 induced lytic replication, a risk factor for carcinoma development, although less efficiently than M81. The panel of viruses induced tumors in immunocompromised mice with variable speed and efficacy that did not strictly mirror their in vitro characteristics, suggesting that additional parameters play an important role. We found that YCCEL1 and M81 infected primary epithelial cells, gastric carcinoma cells and gastric spheroids more efficiently than Akata or B95-8. Reciprocally, Akata and B95-8 had a stronger tropism for B cells than YCCEL1 or M81. These data suggest that different EBV strains will induce the development of lymphoid tumors with variable efficacy in immunocompromised patients and that there is a parallel between the cell tropism of the viral strains and the lineage of the tumors they induce. Thus, EBV strains can be endowed with properties that will influence their transforming abilities and the type of tumor they induce.
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Affiliation(s)
- Ming-Han Tsai
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany
| | - Xiaochen Lin
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany
| | - Anatoliy Shumilov
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany
| | - Katharina Bernhardt
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany
| | - Regina Feederle
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany.,Institute for Diabetes and Obesitas, Monoclonal Antibody Core Facility, German Research Center for Environmental Health, Helmholtz Zentrum München, 81377 Munich, Germany
| | - Remy Poirey
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany
| | | | - Bruno Pereira
- Differentiation and Cancer Group, IPATIMUP, Rua Dr Roberto Frias s/n, 4200 - 465 Porto, Portugal
| | - Raquel Almeida
- Differentiation and Cancer Group, IPATIMUP, Rua Dr Roberto Frias s/n, 4200 - 465 Porto, Portugal
| | - Henri-Jacques Delecluse
- German Cancer Research Centre (DKFZ), Unit F100, 69120 Heidelberg, Germany.,Inserm unit U1074, DKFZ, 69120 Heidelberg, Germany
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32
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Moon JW, Kong SK, Kim BS, Kim HJ, Lim H, Noh K, Kim Y, Choi JW, Lee JH, Kim YS. IFNγ induces PD-L1 overexpression by JAK2/STAT1/IRF-1 signaling in EBV-positive gastric carcinoma. Sci Rep 2017; 7:17810. [PMID: 29259270 PMCID: PMC5736657 DOI: 10.1038/s41598-017-18132-0] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 12/06/2017] [Indexed: 12/21/2022] Open
Abstract
Programmed death-ligand 1 (PD-L1) acts as an immune checkpoint inhibitor in various cancers. PD-L1 is known to be more frequently expressed in EBV (+) gastric cancer (GC). However, the mechanisms underlying the regulation of PD-L1 expression in EBV (+) GC remain unclear. We investigated the basal and inducible PD-L1 expressions in GC cells. PD-L1 expression was upregulated upon treatment with IFNγ in both EBV (-) and EBV (+) GC cells. Upon stimulation with the same concentration of IFNγ for 24 h, EBV (+) SNU-719 cells showed dramatically higher PD-L1 expression levels by activating JAK2/STAT1/IRF-1 signaling than those of EBV (-) AGS cells. PD-L1 promoter assays, chromatin immunoprecipitation, and electrophoretic mobility shift assays revealed that IFNγ-inducible PD-L1 overexpression is primarily mediated by the putative IRF-1α site of the PD-L1 promoter in EBV (+) SNU-719 cells. Moreover, EBNA1 knockdown reduced both constitutive and IFNγ-inducible PD-L1 promoter activity by decreasing the transcript and protein levels of JAK2 and subsequently STAT1/IRF-1/PD-L1 signaling. EBNA1 is suggested to be moderately enhance both constitutive and IFNγ-inducible PD-L1 expression in EBV (+) GC cells. Thus, the signaling proteins and EBNA1 that regulate PD-L1 expression are potential therapeutic targets in EBV (+) GC.
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Affiliation(s)
- Ji Wook Moon
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea
| | - Su-Kang Kong
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea
| | - Byung Soo Kim
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyun Ji Kim
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyangsoon Lim
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea
| | - Kyeonga Noh
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea
| | - Younghye Kim
- Department of Pathology, Korea University Ansan Hospital, Ansan, Republic of Korea
| | - Jung-Woo Choi
- Department of Pathology, Korea University Ansan Hospital, Ansan, Republic of Korea
| | - Ju-Han Lee
- Department of Pathology, Korea University Ansan Hospital, Ansan, Republic of Korea
| | - Young-Sik Kim
- Department of Pathology, Korea University College of Medicine, Seoul, Republic of Korea. .,Department of Pathology, Korea University Ansan Hospital, Ansan, Republic of Korea.
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Almeida JFM, Campos AH, Marcello MA, Bufalo NE, Rossi CL, Amaral LHP, Marques AB, Cunha LL, Alvarenga CA, Tincani PC, Tincani AJ, Ward LS. Investigation on the association between thyroid tumorigeneses and herpesviruses. J Endocrinol Invest 2017; 40:823-829. [PMID: 28276007 DOI: 10.1007/s40618-017-0609-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/02/2017] [Indexed: 12/11/2022]
Abstract
Herpesviruses have been associated with various human malignancies and with thyroid autoimmunity. Aiming to investigate the presence of these viruses in thyroid nodules, we analyzed serum and thyroid tissue from 183 patients (83 benign and 100 malignant thyroid nodules). We also obtained 104 normal thyroid tissues extracted from the contralateral lobe of these patients. We used ELISA to screen the serology of all patients and a real-time quantitative PCR to analyze thyroid tissue viral load in antibody-positive patients. In addition, the presence of herpesviruses was tested by histological analysis in 20 EBV-positive tissues using the expression of LMP-1 by immunohistochemistry (IHC) and EBER by in situ hybridization (ISH). There was no evidence of HSV-2 or CMV DNA, but we found EBV DNA sequences in 29 (16%) thyroid tissue samples. We also found 7 positive EBV cases out of 104 normal tissues. Viral load was higher in tumors than in their respective normal tissues (p = 0.0002). ISH analysis revealed EBER expression in 11 out of 20 (52%) EBV-positive tissues, mostly in malignant cases (8/11, 73%). The presence of high EBV copy numbers in thyroid tumors and the expression of EBER only in malignant cases suggest an association between EBV and thyroid malignancies. However, we did not find any association between the presence of EBV and/or its viral load and any clinical or pathological tumor feature. Further studies aiming to clarify the mechanisms of EBV infection in thyroid cells are necessary to support a possible role in the development of thyroid cancer.
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Affiliation(s)
- J F M Almeida
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - A H Campos
- Department of Anatomic Pathology, AC Camargo Cancer Center, Taguá Street, 440, Liberdade, São Paulo, SP, 01508-010, Brazil
| | - M A Marcello
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - N E Bufalo
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - C L Rossi
- Clinical Pathology Department, Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Vital Brasil Street, 251, Cidade Universitária, Campinas, São Paulo, 13083-888, Brazil
| | - L H P Amaral
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - A B Marques
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - L L Cunha
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - C A Alvarenga
- Laboratory of Pathology, Clinical Pathology Institute (IPC), Av. Orosimbo Maia, 165, Vila Itapura, Campinas, São Paulo, 13023-002, Brazil
| | - P C Tincani
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil
| | - A J Tincani
- Head and Neck Surgery Department, University of Campinas Teaching Hospital (HC-Unicamp), Vital Brasil Street, 251, Cidade Universitária, Campinas, SP, 13083-888, Brazil
| | - L S Ward
- Laboratory of Cancer Molecular Genetics (Gemoca), Faculty of Medical Sciences, University of Campinas (FCM-Unicamp), Tessália Vieira de Camargo Street, 126, Cidade Universitária, Campinas, São Paulo, 13083-887, Brazil.
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朱 晓, 李 夏, 李 素, 于 红. Advances in research of Epstein-Barr virus-associated gastric carcinoma. Shijie Huaren Xiaohua Zazhi 2017; 25:1375. [DOI: 10.11569/wcjd.v25.i15.1375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Kim DH, Chang MS, Yoon CJ, Middeldorp JM, Martinez OM, Byeon SJ, Rha SY, Kim SH, Kim YS, Woo JH. Epstein-Barr virus BARF1-induced NFκB/miR-146a/SMAD4 alterations in stomach cancer cells. Oncotarget 2016; 7:82213-82227. [PMID: 27438138 PMCID: PMC5347686 DOI: 10.18632/oncotarget.10511] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/12/2016] [Indexed: 12/21/2022] Open
Abstract
Epstein-Barr virus (EBV)-encoded BamHI-A rightward frame 1 (BARF1) is a putative viral oncogene in EBV-infected stomach cancer. The aim of the present study was to investigate BARF1-induced cellular protein and microRNA alterations. In this study, BARF1-expressing stomach cancer cells showed a high rate of proliferation, high levels of NFκB, and miR-146a upregulation, which was reversed by NFκB knockdown. During BARF1-induced NFκB upregulation, hCSF1 receptor level was unchanged. Knockdown of BARF1 in the naturally EBV-infected YCCEL1 stomach cancer cells suppressed cell proliferation, and downregulated NFκB and miR-146a. SMAD4 was identified as a miR-146a target and was downregulated in BARF1-expressing cells, whereas SMAD4 expression was restored by anti-miR-146a. Knockdown of BARF1 in YCCEL1 cells upregulated SMAD4, and this effect was reversed by miR-146a overexpression. Transfection of BARF1-expressing cells with pCEP4-SMAD4 abolished the cell proliferating effect of BARF1. In stomach cancer tissues, miR-146a was expressed at higher levels, and more frequent NFκB nuclear positivity immunohistochemically, but not of SMAD4 nuclear loss was found in the EBV-positive group compared with the EBV-negative group. In conclusion, EBV-encoded BARF1 promotes cell proliferation in stomach cancer by upregulating NFκB and miR-146a and downregulating SMAD4, thereby contributing to EBV-induced stomach cancer progression.
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Affiliation(s)
- Dong Ha Kim
- Asan Institute for Life Sciences, Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Mee Soo Chang
- Department of Pathology, Seoul National University Boramae Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Chan Jin Yoon
- Asan Institute for Life Sciences, Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jaap M. Middeldorp
- Department of Pathology, VU University Medical Center, Amsterdam, the Netherlands
| | - Olivia M. Martinez
- Department of Surgery/Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA, USA
| | - Sun-ju Byeon
- Department of Pathology, Seoul National University Boramae Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sun Young Rha
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sung Han Kim
- Asan Institute for Life Sciences, Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yang Soo Kim
- Asan Institute for Life Sciences, Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jun Hee Woo
- Asan Institute for Life Sciences, Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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van Diemen FR, Kruse EM, Hooykaas MJG, Bruggeling CE, Schürch AC, van Ham PM, Imhof SM, Nijhuis M, Wiertz EJHJ, Lebbink RJ. CRISPR/Cas9-Mediated Genome Editing of Herpesviruses Limits Productive and Latent Infections. PLoS Pathog 2016; 12:e1005701. [PMID: 27362483 PMCID: PMC4928872 DOI: 10.1371/journal.ppat.1005701] [Citation(s) in RCA: 198] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 05/23/2016] [Indexed: 12/15/2022] Open
Abstract
Herpesviruses infect the majority of the human population and can cause significant morbidity and mortality. Herpes simplex virus (HSV) type 1 causes cold sores and herpes simplex keratitis, whereas HSV-2 is responsible for genital herpes. Human cytomegalovirus (HCMV) is the most common viral cause of congenital defects and is responsible for serious disease in immuno-compromised individuals. Epstein-Barr virus (EBV) is associated with infectious mononucleosis and a broad range of malignancies, including Burkitt’s lymphoma, nasopharyngeal carcinoma, Hodgkin’s disease, and post-transplant lymphomas. Herpesviruses persist in their host for life by establishing a latent infection that is interrupted by periodic reactivation events during which replication occurs. Current antiviral drug treatments target the clinical manifestations of this productive stage, but they are ineffective at eliminating these viruses from the infected host. Here, we set out to combat both productive and latent herpesvirus infections by exploiting the CRISPR/Cas9 system to target viral genetic elements important for virus fitness. We show effective abrogation of HCMV and HSV-1 replication by targeting gRNAs to essential viral genes. Simultaneous targeting of HSV-1 with multiple gRNAs completely abolished the production of infectious particles from human cells. Using the same approach, EBV can be almost completely cleared from latently infected EBV-transformed human tumor cells. Our studies indicate that the CRISPR/Cas9 system can be effectively targeted to herpesvirus genomes as a potent prophylactic and therapeutic anti-viral strategy that may be used to impair viral replication and clear latent virus infection. Herpesviruses are large DNA viruses that are carried by almost 100% of the adult human population. Herpesviruses include several important human pathogens, such as herpes simplex viruses (HSV) type 1 and 2 (causing cold sores and genital herpes, respectively), human cytomegalovirus (HCMV; the most common viral cause of congenital defects, and responsible for serious disease in immuno-compromised individuals), and Epstein-Barr virus (EBV; associated with infectious mononucleosis and a wide range of malignancies). Current antiviral drug treatments are not effective in clearing herpesviruses from infected individuals. Therefore, there is a need for alternative strategies to combat these pathogenic viruses and prevent or cure herpesvirus-associated diseases. Here, we have assessed whether a direct attack of herpesvirus genomes within virus-infected cells can inactivate these viruses. For this, we have made use of the recently developed CRISPR/Cas9 genome-engineering system to target and alter specific regions within the genome of these viruses. By targeting sites in the genomes of three different herpesviruses (HSV-1, HCMV, and EBV), we show complete inhibition of viral replication and in some cases even eradication of the viral genomes from infected cells. The findings presented in this study open new avenues for the development of therapeutic strategies to combat pathogenic human herpesviruses using novel genome-engineering technologies.
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Affiliation(s)
- Ferdy R. van Diemen
- Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Elisabeth M. Kruse
- Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | | | - Anita C. Schürch
- Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Petra M. van Ham
- Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Saskia M. Imhof
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Monique Nijhuis
- Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Robert Jan Lebbink
- Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
- * E-mail:
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Highly Efficient CRISPR/Cas9-Mediated Cloning and Functional Characterization of Gastric Cancer-Derived Epstein-Barr Virus Strains. J Virol 2016; 90:4383-93. [PMID: 26889033 DOI: 10.1128/jvi.00060-16] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Accepted: 02/10/2016] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED The Epstein-Barr virus (EBV) is etiologically linked to approximately 10% of gastric cancers, in which viral genomes are maintained as multicopy episomes. EBV-positive gastric cancer cells are incompetent for progeny virus production, making viral DNA cloning extremely difficult. Here we describe a highly efficient strategy for obtaining bacterial artificial chromosome (BAC) clones of EBV episomes by utilizing a CRISPR/Cas9-mediated strand break of the viral genome and subsequent homology-directed repair. EBV strains maintained in two gastric cancer cell lines (SNU719 and YCCEL1) were cloned, and their complete viral genome sequences were determined. Infectious viruses of gastric cancer cell-derived EBVs were reconstituted, and the viruses established stable latent infections in immortalized keratinocytes. While Ras oncoprotein overexpression caused massive vacuolar degeneration and cell death in control keratinocytes, EBV-infected keratinocytes survived in the presence of Ras expression. These results implicate EBV infection in predisposing epithelial cells to malignant transformation by inducing resistance to oncogene-induced cell death. IMPORTANCE Recent progress in DNA-sequencing technology has accelerated EBV whole-genome sequencing, and the repertoire of sequenced EBV genomes is increasing progressively. Accordingly, the presence of EBV variant strains that may be relevant to EBV-associated diseases has begun to attract interest. Clearly, the determination of additional disease-associated viral genome sequences will facilitate the identification of any disease-specific EBV variants. We found that CRISPR/Cas9-mediated cleavage of EBV episomal DNA enabled the cloning of disease-associated viral strains with unprecedented efficiency. As a proof of concept, two gastric cancer cell-derived EBV strains were cloned, and the infection of epithelial cells with reconstituted viruses provided important clues about the mechanism of EBV-mediated epithelial carcinogenesis. This experimental system should contribute to establishing the relationship between viral genome variation and EBV-associated diseases.
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Role of Viral miRNAs and Epigenetic Modifications in Epstein-Barr Virus-Associated Gastric Carcinogenesis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:6021934. [PMID: 26977250 PMCID: PMC4764750 DOI: 10.1155/2016/6021934] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 01/12/2016] [Accepted: 01/14/2016] [Indexed: 01/26/2023]
Abstract
MicroRNAs are short (21–23 nucleotides), noncoding RNAs that typically silence posttranscriptional gene expression through interaction with target messenger RNAs. Currently, miRNAs have been identified in almost all studied multicellular eukaryotes in the plant and animal kingdoms. Additionally, recent studies reported that miRNAs can also be encoded by certain single-cell eukaryotes and by viruses. The vast majority of viral miRNAs are encoded by the herpesviruses family. These DNA viruses including Epstein-Barr virus encode their own miRNAs and/or manipulate the expression of cellular miRNAs to facilitate respective infection cycles. Modulation of the control pathways of miRNAs expression is often involved in the promotion of tumorigenesis through a specific cascade of transduction signals. Notably, latent infection with Epstein-Barr virus is considered liable of causing several types of malignancies, including the majority of gastric carcinoma cases detected worldwide. In this review, we describe the role of the Epstein-Barr virus in gastric carcinogenesis, summarizing the functions of the Epstein-Barr virus-encoded viral proteins and related epigenetic alterations as well as the roles of Epstein-Barr virus-encoded and virally modulated cellular miRNAs.
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Identification of Novel Small Organic Compounds with Diverse Structures for the Induction of Epstein-Barr Virus (EBV) Lytic Cycle in EBV-Positive Epithelial Malignancies. PLoS One 2015; 10:e0145994. [PMID: 26717578 PMCID: PMC4696655 DOI: 10.1371/journal.pone.0145994] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 11/19/2015] [Indexed: 11/20/2022] Open
Abstract
Phorbol esters, which are protein kinase C (PKC) activators, and histone deacetylase (HDAC) inhibitors, which cause enhanced acetylation of cellular proteins, are the main classes of chemical inducers of Epstein-Barr virus (EBV) lytic cycle in latently EBV-infected cells acting through the PKC pathway. Chemical inducers which induce EBV lytic cycle through alternative cellular pathways may aid in defining the mechanisms leading to lytic cycle reactivation and improve cells' responsiveness towards lytic induction. We performed a phenotypic screening on a chemical library of 50,240 novel small organic compounds to identify novel class(es) of strong inducer(s) of EBV lytic cycle in gastric carcinoma (GC) and nasopharyngeal carcinoma (NPC) cells. Five hit compounds were selected after three successive rounds of increasingly stringent screening. All five compounds are structurally diverse from each other and distinct from phorbol esters or HDAC inhibitors. They neither cause hyperacetylation of histone proteins nor significant PKC activation at their working concentrations, suggesting that their biological mode of action are distinct from that of the known chemical inducers. Two of the five compounds with rapid lytic-inducing action were further studied for their mechanisms of induction of EBV lytic cycle. Unlike HDAC inhibitors, lytic induction by both compounds was not inhibited by rottlerin, a specific inhibitor of PKCδ. Interestingly, both compounds could cooperate with HDAC inhibitors to enhance EBV lytic cycle induction in EBV-positive epithelial cancer cells, paving way for the development of strategies to increase cells' responsiveness towards lytic reactivation. One of the two compounds bears structural resemblance to iron chelators and the other strongly activates the MAPK pathways. These structurally diverse novel organic compounds may represent potential new classes of chemicals that can be used to investigate any alternative mechanism(s) leading to EBV lytic cycle reactivation from latency.
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Epstein-Barr Virus MicroRNA miR-BART20-5p Suppresses Lytic Induction by Inhibiting BAD-Mediated caspase-3-Dependent Apoptosis. J Virol 2015; 90:1359-68. [PMID: 26581978 DOI: 10.1128/jvi.02794-15] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 11/08/2015] [Indexed: 01/22/2023] Open
Abstract
UNLABELLED Epstein-Barr virus (EBV) is a human gammaherpesvirus associated with a variety of tumor types. EBV can establish latency or undergo lytic replication in host cells. In general, EBV remains latent in tumors and expresses a limited repertoire of latent proteins to avoid host immune surveillance. When the lytic cycle is triggered by some as-yet-unknown form of stimulation, lytic gene expression and progeny virus production commence. Thus far, the exact mechanism of EBV latency maintenance and the in vivo triggering signal for lytic induction have yet to be elucidated. Previously, we have shown that the EBV microRNA miR-BART20-5p directly targets the immediate early genes BRLF1 and BZLF1 as well as Bcl-2-associated death promoter (BAD) in EBV-associated gastric carcinoma. In this study, we found that both mRNA and protein levels of BRLF1 and BZLF1 were suppressed in cells following BAD knockdown and increased after BAD overexpression. Progeny virus production was also downregulated by specific knockdown of BAD. Our results demonstrated that caspase-3-dependent apoptosis is a prerequisite for BAD-mediated EBV lytic cycle induction. Therefore, our data suggest that miR-BART20-5p plays an important role in latency maintenance and tumor persistence of EBV-associated gastric carcinoma by inhibiting BAD-mediated caspase-3-dependent apoptosis, which would trigger immediate early gene expression. IMPORTANCE EBV has an ability to remain latent in host cells, including EBV-associated tumor cells hiding from immune surveillance. However, the exact molecular mechanisms of EBV latency maintenance remain poorly understood. Here, we demonstrated that miR-BART20-5p inhibited the expression of EBV immediate early genes indirectly, by suppressing BAD-induced caspase-3-dependent apoptosis, in addition to directly, as we previously reported. Our study suggests that EBV-associated tumor cells might endure apoptotic stress to some extent and remain latent with the aid of miR-BART20-5p. Blocking the expression or function of BART20-5p may expedite EBV-associated tumor cell death via immune attack and apoptosis.
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Latent Expression of the Epstein-Barr Virus (EBV)-Encoded Major Histocompatibility Complex Class I TAP Inhibitor, BNLF2a, in EBV-Positive Gastric Carcinomas. J Virol 2015; 89:10110-4. [PMID: 26178981 DOI: 10.1128/jvi.01110-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/07/2015] [Indexed: 12/14/2022] Open
Abstract
The Epstein-Barr virus (EBV) BNLF2a gene product provides immune evasion properties to infected cells through inhibition of transporter associated with antigen processing (TAP)-mediated transport of antigen peptides. Although BNLF2a is considered to be a lytic gene, we demonstrate that it is expressed in nearly half of the EBV-associated gastric carcinomas analyzed. Further, we show that BNLF2a expression is dissociated from lytic gene expression. BNLF2a is therefore expressed in this latency setting, potentially helping protect the infected tumor cells from immunosurveillance.
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Profiling of Virus-Encoded MicroRNAs in Epstein-Barr Virus-Associated Gastric Carcinoma and Their Roles in Gastric Carcinogenesis. J Virol 2015; 89:5581-91. [PMID: 25740983 DOI: 10.1128/jvi.03639-14] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 03/01/2015] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Epstein-Barr virus (EBV) is one of the major oncogenic viruses and is found in nearly 10% of gastric carcinomas. EBV is known to encode its own microRNAs (miRNAs); however, their roles have not been fully investigated. The present report is the largest series to comprehensively profile the expression of 44 known EBV miRNAs in tissue samples from patients with EBV-associated gastric carcinoma. Several miRNAs were highly expressed in EBV-associated gastric carcinoma, and in silico analysis revealed that the target genes of these EBV miRNAs had functions associated with cancer-related pathways, especially the regulation of apoptosis. Apoptosis was reduced in EBV-associated gastric carcinoma tissue samples, and gastric carcinoma cell lines infected with EBV exhibited downregulation of the proapoptotic protein Bid (the BH3-interacting domain death agonist), a member of the Bcl-2 family. The luciferase activity of the reporter vector containing the 3' untranslated region of BID was inhibited by an ebv-miR-BART4-5p mimic in gastric cancer cell lines. Transfection of an ebv-miR-BART4-5p mimic reduced Bid expression in EBV-negative cell lines, leading to reduced apoptosis under serum deprivation. The inhibition of ebv-miR-BART4-5p expression was associated with partial recovery of Bid levels in EBV-positive cell lines. The results demonstrated the antiapoptotic role of EBV miRNA via regulation of Bid expression in EBV-associated gastric carcinoma. These findings provide novel insights in the roles of EBV miRNAs in gastric carcinogenesis, which would be a potential therapeutic target. IMPORTANCE This report is the largest series to comprehensively profile the expression of 44 known EBV miRNAs in clinical samples from EBV-associated gastric carcinoma patients. Of the EBV miRNAs, ebv-miR-BART4-5p plays an important role in gastric carcinogenesis via regulation of apoptosis.
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Shinozaki-Ushiku A, Kunita A, Fukayama M. Update on Epstein-Barr virus and gastric cancer (review). Int J Oncol 2015; 46:1421-34. [PMID: 25633561 DOI: 10.3892/ijo.2015.2856] [Citation(s) in RCA: 215] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/29/2014] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is a distinct subtype that accounts for nearly 10% of gastric carcinomas. EBVaGC is defined by monoclonal proliferation of carcinoma cells with latent EBV infection, as demonstrated by EBV-encoded small RNA (EBER) in situ hybridization. EBVaGC has characteristic clinicopathological features, including predominance among males, a proximal location in the stomach, lymphoepithelioma-like histology and a favorable prognosis. EBVaGC belongs to latency type I or II, in which EBERs, EBNA-1, BARTs, LMP-2A and BART miRNAs are expressed. Previous studies have shown that some EBV latent genes have oncogenic properties. Recent advances in genome-wide and comprehensive molecular analyses have demonstrated that both genetic and epigenetic changes contribute to EBVaGC carcinogenesis. Genetic changes that are characteristic of EBVaGC include frequent mutations in PIK3CA and ARID1A and amplification of JAK2 and PD-L1/L2. Global CpG island hypermethylation, which induces epigenetic silencing of tumor suppressor genes, is also a unique feature of EBVaGC and is considered to be crucial for its carcinogenesis. Furthermore, post-transcriptional gene expression regulation by cellular and/or EBV-derived microRNAs has attracted considerable attention. These abnormalities result in significant alterations in gene expression related to cell proliferation, apoptosis, migration and immune signaling pathways. In the present review we highlight the latest findings on EBVaGC from clinicopathological and molecular perspectives to provide a better understanding of EBV involvement in gastric carcinogenesis.
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Affiliation(s)
- Aya Shinozaki-Ushiku
- Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Akiko Kunita
- Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Masashi Fukayama
- Department of Pathology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
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Kim SY, Park C, Kim HJ, Park J, Hwang J, Kim JI, Choi MG, Kim S, Kim KM, Kang MS. Deregulation of immune response genes in patients with Epstein-Barr virus-associated gastric cancer and outcomes. Gastroenterology 2015; 148:137-147.e9. [PMID: 25254613 DOI: 10.1053/j.gastro.2014.09.020] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2014] [Revised: 09/14/2014] [Accepted: 09/15/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Patients with Epstein-Barr virus-associated gastric carcinoma (EBVaGC) have a better prognosis than those with gastric cancer not associated with EBV infection (EBVnGC). This is partly because EBV infection recruits lymphocytes, which infiltrate the tumor. A high degree of tumor heterogeneity is likely to be associated with poor response. We investigated differences in gene expression patterns between EBVaGC and EBVnGC. METHODS We used gene expression profile analysis to compare tumor and nontumor gastric tissues from 12 patients with EBVaGC and 14 patients with EBVnGC. Findings were validated by whole transcriptome RNAseq and real-time quantitative polymerase chain reaction analyses. CD3(+) primary T cells were isolated from human blood samples; migration of these cells and of Jurkat cells were measured in culture with EBV-infected and uninfected gastric cancer cells. RESULTS Based on Pearson correlation matrix analysis, EBVaGCs had a higher degree of homogeneity than EBVnGCs. Although 4550 genes were differentially expressed between tumor and nontumor gastric tissues of patients with EBVnGC, only 186 genes were differentially expressed between tumor and nontumor gastric tissues of patients with EBVaGC (P < .001). This finding supports the concept that EBVaGCs have fewer genetic and epigenetic alterations than EBVnGCs. Expression of major histocompatibility complex class II genes and genes that regulate chemokine activity were more often deregulated in EBVaGCs compared with nontumor tissues. In culture, more T cells migrated to EBV-infected gastric cancer cells than to uninfected cells; migration was blocked with a neutralizing antibody against CXCR3 (a receptor for many chemokines). CONCLUSIONS Fewer genes are deregulated in EBVaGC than in EBVnGC. Most changes in EBVaGCs occur in immune response genes. These changes might allow EBVaGC to recruit reactive immune cells; this might contribute to the better outcomes of these patients compared with those with EBVnGC.
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Affiliation(s)
- Sun Young Kim
- Samsung Advanced Institute for Health Sciences and Technology, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea; Samsung Biomedical Research Institute, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Charny Park
- Ewha Research Center for Systems Biology, Ewha Womans University, Seoul, Korea
| | - Ha-Jung Kim
- Samsung Advanced Institute for Health Sciences and Technology, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jihyun Park
- Samsung Advanced Institute for Health Sciences and Technology, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea; Samsung Biomedical Research Institute, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jinha Hwang
- Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Korea
| | - Jong-Il Kim
- Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Korea; Department of Biochemistry, Seoul National University College of Medicine, Seoul, Korea; Genomic Medicine Institute, Medical Research Center, Seoul National University, Seoul, Korea
| | - Min Gew Choi
- Department of Surgery, Center for Gastric Cancer, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Kim
- Department of Surgery, Center for Gastric Cancer, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyoung-Mee Kim
- Samsung Biomedical Research Institute, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea; Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Myung-Soo Kang
- Samsung Advanced Institute for Health Sciences and Technology, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea; Samsung Biomedical Research Institute, Center for Future Sciences, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
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Liang Q, Yao X, Tang S, Zhang J, Yau TO, Li X, Tang CM, Kang W, Lung RWM, Li JW, Chan TF, Xing R, Lu Y, Lo KW, Wong N, To KF, Yu C, Chan FKL, Sung JJY, Yu J. Integrative identification of Epstein-Barr virus-associated mutations and epigenetic alterations in gastric cancer. Gastroenterology 2014; 147:1350-62.e4. [PMID: 25173755 DOI: 10.1053/j.gastro.2014.08.036] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 08/21/2014] [Accepted: 08/23/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS The mechanisms by which Epstein-Barr virus (EBV) contributes to the development of gastric cancer are unclear. We investigated EBV-associated genomic and epigenomic variations in gastric cancer cells and tumors. METHODS We performed whole-genome, transcriptome, and epigenome sequence analyses of a gastric adenocarcinoma cell line (AGS cells), before and after EBV infection. We then looked for alterations in gastric tumor samples, with (n = 34) or without (n = 100) EBV infection, collected from patients at the Prince of Wales Hospital, Chinese University of Hong Kong (from 1998 through 2004), or the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China (from 1999 through 2006). RESULTS Transcriptome analysis showed that infected cells expressed 9 EBV genes previously detected in EBV-associated gastric tumors and 71 EBV genes not previously reported in gastric tumors. Ten viral genes that had not been reported previously in gastric cancer but were expressed most highly in EBV-infected cells also were expressed in primary EBV-positive gastric tumors. Whole-genome sequence analysis identified 45 EBV-associated nonsynonymous mutations. These mutations, in genes such as AKT2, CCNA1, MAP3K4, and TGFBR1, were associated significantly with EBV-positive gastric tumors, compared with EBV-negative tumors. An activating mutation in AKT2 was associated with reduced survival times of patients with EBV-positive gastric cancer (P = .006); this mutation was found to dysregulate mitogen-activated protein kinase signaling. Integrated epigenome and transcriptome analyses identified 216 genes transcriptionally down-regulated by EBV-associated hypermethylation; methylation of ACSS1, FAM3B, IHH, and TRABD increased significantly in EBV-positive tumors. Overexpression of Indian hedgehog (IHH) and TraB domain containing (TRABD) increased proliferation and colony formation of gastric cancer cells, whereas knockdown of these genes reduced these activities. We found 5 signaling pathways (axon guidance, focal adhesion formation, interactions among cytokines and receptors, mitogen-activated protein kinase signaling, and actin cytoskeleton regulation) to be affected commonly by EBV-associated genomic and epigenomic alterations. CONCLUSIONS By using genomic, transcriptome, and epigenomic comparisons of EBV infected vs noninfected gastric cancer cells and tumor samples, we identified alterations in genes, gene expression, and methylation that affect different signaling networks. These might be involved in EBV-associated gastric carcinogenesis.
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Affiliation(s)
- Qiaoyi Liang
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | | | | | - Jingwan Zhang
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Tung On Yau
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Xiaoxing Li
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Ceen-Ming Tang
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Wei Kang
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Raymond W M Lung
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Jing Woei Li
- School of Life Sciences, Hong Kong Bioinformatics Centre, The Chinese University of Hong Kong, Hong Kong, China
| | - Ting Fung Chan
- School of Life Sciences, Hong Kong Bioinformatics Centre, The Chinese University of Hong Kong, Hong Kong, China
| | - Rui Xing
- Laboratory of Molecular Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital/Institute, Beijing, China
| | - Youyong Lu
- Laboratory of Molecular Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital/Institute, Beijing, China
| | - Kwok Wai Lo
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Nathalie Wong
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Ka Fai To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | | | - Francis K L Chan
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Joseph J Y Sung
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Jun Yu
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China.
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Nishikawa J, Yoshiyama H, Iizasa H, Kanehiro Y, Nakamura M, Nishimura J, Saito M, Okamoto T, Sakai K, Suehiro Y, Yamasaki T, Oga A, Yanai H, Sakaida I. Epstein-barr virus in gastric carcinoma. Cancers (Basel) 2014; 6:2259-74. [PMID: 25386788 PMCID: PMC4276965 DOI: 10.3390/cancers6042259] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 09/27/2014] [Accepted: 10/28/2014] [Indexed: 12/28/2022] Open
Abstract
The Epstein-Barr virus (EBV) is detected in about 10% of gastric carcinoma cases throughout the world. In EBV-associated gastric carcinoma, all tumor cells harbor the clonal EBV genome. Gastric carcinoma associated with EBV has distinct clinicopathological features, occurs predominately in men and in younger-aged individuals, and presents a generally diffuse histological type. Most cases of EBV-associated gastric carcinoma exhibit a histology rich in lymphocyte infiltration. The immunological reactiveness in the host may represent a relatively preferable prognosis in EBV-positive cases. This fact highlights the important role of EBV in the development of EBV-associated gastric carcinoma. We have clearly proved direct infection of human gastric epithelialcells by EBV. The infection was achieved by using a recombinant EBV. Promotion of growth by EBV infection was observed in the cells. Considerable data suggest that EBV may directly contribute to the development of EBV-associated GC. This tumor-promoting effect seems to involve multiple mechanisms, because EBV affects several host proteins and pathways that normally promote apoptosis and regulate cell proliferation.
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Affiliation(s)
- Jun Nishikawa
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Hironori Yoshiyama
- Department of Microbiology, Shimane University Faculty of Medicine, 89-1 Enyacho, Izumo City, Shimane 693-8501, Japan.
| | - Hisashi Iizasa
- Department of Microbiology, Shimane University Faculty of Medicine, 89-1 Enyacho, Izumo City, Shimane 693-8501, Japan.
| | - Yuichi Kanehiro
- Department of Microbiology, Shimane University Faculty of Medicine, 89-1 Enyacho, Izumo City, Shimane 693-8501, Japan.
| | - Munetaka Nakamura
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Junichi Nishimura
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Mari Saito
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Takeshi Okamoto
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Kouhei Sakai
- Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Yutaka Suehiro
- Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Takahiro Yamasaki
- Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Atsunori Oga
- Department of Pathology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
| | - Hideo Yanai
- Department of Clinical Research, National Hospital Organization Kanmon Medical Center, 1-1 Sotoura, Chofu, Shimonoseki, Yamaguchi 752-8510, Japan.
| | - Isao Sakaida
- Department of Gastroenterology and Hepatology, Yamaguchi University Graduate School of Medicine, Minami-Kogushi 1-1-1, Ube, Yamaguchi 755-8505, Japan.
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Kim H, Choi H, Lee SK. Epstein-Barr virus miR-BART20-5p regulates cell proliferation and apoptosis by targeting BAD. Cancer Lett 2014; 356:733-42. [PMID: 25449437 DOI: 10.1016/j.canlet.2014.10.023] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 10/22/2014] [Accepted: 10/22/2014] [Indexed: 12/11/2022]
Abstract
Although Epstein-Barr virus (EBV) BamHI A rightward transcript (BART) microRNAs (miRNAs) are ubiquitously expressed in EBV-associated tumors, the role of most BART miRNAs is unclear. In this study, we showed that Bcl-2-associated death promoter (BAD) expression was significantly lower in EBV-infected AGS-EBV cells than in EBV-negative AGS cells and investigated whether BART miRNAs target BAD. Using bioinformatics analysis, five BART miRNAs showing seed match with the 3' untranslated region (3'-UTR) of BAD were selected. Of these, only miR-BART20-5p reduced BAD expression when individually transfected into AGS cells. A luciferase assay revealed that miR-BART20-5p directly targets BAD. The expression of BAD mRNA and protein was decreased by miR-BART20-5p and increased by an inhibitor of miR-BART20-5p. PE-Annexin V staining and cell proliferation assays showed that miR-BART20-5p reduced apoptosis and enhanced cell growth. Furthermore, miR-BART20-5p increased chemoresistance to 5-fluorouracil and docetaxel. Our data suggest that miR-BART20-5p contributes to tumorigenesis of EBV-associated gastric carcinoma by directly targeting the 3'-UTR of BAD.
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Affiliation(s)
- Hyoji Kim
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, South Korea
| | - Hoyun Choi
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, South Korea
| | - Suk Kyeong Lee
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, South Korea.
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MicroRNA miR-BART20-5p stabilizes Epstein-Barr virus latency by directly targeting BZLF1 and BRLF1. J Virol 2014; 88:9027-37. [PMID: 24899173 DOI: 10.1128/jvi.00721-14] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Epstein-Barr virus (EBV) is a human herpesvirus associated with various tumors. Rather than going through the lytic cycle, EBV maintains latency by limiting the expression of viral genes in tumors. Viral microRNAs (miRNAs) of some herpesviruses have been reported to directly target immediate early genes and suppress lytic induction. In this study, we investigated whether BamHI-A rightward transcript (BART) miRNAs targeted two EBV immediate early genes, BZLF1 and BRLF1. Bioinformatic analysis predicted that 12 different BART miRNAs would target BRLF1. Of these, the results of a luciferase reporter assay indicated that only one interacted with the 3' untranslated region (UTR) of BRLF1: miR-BART20-5p. miR-BART20-5p's effect on gene expression involved two putative seed match sites in the BRLF1 3' UTR, but a mutant version of the miRNA, miR-BART20-5pm, had no effect on expression. As expected from the fact that the entire 3' UTR of BZLF1 resides within the 3' UTR of BRLF1, miR-BART20-5p interacted with the 3' UTR of BZLF1 as well. BZLF1 and BRLF1 mRNA and protein expression was suppressed in cells of an AGS cell line infected with the recombinant Akata strain of EBV (AGS-EBV) transfected with a miR-BART20-5p mimic. The expression of various EBV early proteins was also suppressed by the miR-BART20-5p mimic. In contrast, BZLF1 and BRLF1 expression in AGS-EBV cells transfected with a miR-BART20-5p inhibitor was enhanced. Furthermore, progeny virus production was suppressed by the miR-BART20-5p mimic and enhanced by the miR-BART20-5p inhibitor in AGS-EBV cells induced for the lytic cycle. Our data suggest that miR-BART20-5p plays a key role in latency maintenance in EBV-associated tumors by directly targeting immediate early genes. IMPORTANCE Herpesviruses maintain latency using various mechanisms and establish lifelong infection in the host. From time to time, herpesviruses are reactivated and express immediate early genes which trigger a lytic cascade, leading to the production of progeny viruses. Recently, some herpesviruses have been shown to use their own microRNAs (miRNAs) to downregulate immediate early genes to inhibit the lytic cycle. This study presents evidence that EBV also downregulates two immediate early genes by miR-BART20-5p to suppress the lytic cycle and progeny virus production. Overall, this is the first study to report the direct regulation of EBV immediate early genes by an EBV miRNA, implying its likely importance in latency maintenance in EBV-associated tumors.
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Rickinson AB. Co-infections, inflammation and oncogenesis: future directions for EBV research. Semin Cancer Biol 2014; 26:99-115. [PMID: 24751797 DOI: 10.1016/j.semcancer.2014.04.004] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 04/04/2014] [Indexed: 12/24/2022]
Abstract
Epstein-Barr virus (EBV) is aetiologically linked to a wide range of human tumours. Some arise as accidents of the virus' lifestyle in its natural niche, the B lymphoid system; these include B-lymphoproliferative disease of the immunocompromised, Hodgkin Lymphoma, Burkitt Lymphoma and particular forms of diffuse large B cell lymphoma. Interestingly, HIV infection increases the incidence of each of these B cell malignancies, though by different degrees and for different reasons. Other EBV-associated tumours arise through rare viral entry into unnatural target tissues; these include all cases of nasal T/NK cell lymphoma and of undifferentiated nasopharyngeal carcinoma plus a small but significant subset of gastric carcinomas, a tumour type more generally associated with chronic Helicobacter pylori infection. Understanding EBV's involvement in the pathogenesis of these different malignancies is an important long-term goal. This article focuses on two overlapping, but relatively neglected, areas of research that could contribute to that goal. The first addresses the mechanisms whereby coincident infections with other pathogens increase the risk of EBV-positive malignancies, and takes as its paradigm the actions of holoendemic malaria and HIV infections as co-factors in Burkitt lymphomagenesis. The second widens the argument to include both infectious and non-infectious sources of chronic inflammation in the pathogenesis of EBV-positive tumours such as T/NK cell lymphoma, nasopharyngeal carcinoma and gastric carcinoma.
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Affiliation(s)
- A B Rickinson
- School of Cancer Sciences, University of Birmingham, Birmingham, UK.
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50
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Smith C, Khanna R. Epstein?Barr virus-associated malignancies: pathobiology and emerging therapeutic options. MICROBIOLOGY AUSTRALIA 2013. [DOI: 10.1071/ma13041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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