Profiling of Virus-Encoded MicroRNAs in Epstein-Barr Virus-Associated Gastric Carcinoma and Their Roles in Gastric Carcinogenesis

ABSTRACTEpstein-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, andin silicoanalysis 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.IMPORTANCEThis 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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Cytolytic Epstein-Barr Virus Reactivation Therapy for EBV-Associated Gastric Carcinoma

Clinical Oncology and Research ◽

10.31487/j.cor.2020.07.08 ◽

2020 ◽

pp. 1-10

Author(s):

Jaap M. Middeldorp ◽

Zlata Novalić ◽

Sandra A.W.M. Verkuijlen ◽

Astrid E. Greijer ◽

Jaap M. Middeldorp

Keyword(s):

Gastric Carcinoma ◽

Mouse Model ◽

Cell Lines ◽

Epstein Barr Virus ◽

Drug Combinations ◽

Model Systems ◽

Virus Reactivation ◽

Barr Virus ◽

Ebv Reactivation ◽

Epstein Barr

Background: Epstein-Barr virus associated gastric carcinoma (EBVaGC) is considered a distinct GC disease entity, with the virus persisting in a latent phase. Treatment with Epirubicin, Capecitabine and Cisplatin (ECC combination) showed survival benefit in patients with GC in clinical trials (MAGIC study and CRITICS study) when compared to chemotherapy with Capecitabine and Cisplatin (GCb/Cis). Current treatment protocols for GC do not consider virus involvement. Methods: In this study, we tested a CytoLytic Virus Activation (CLVA) strategy consisting of the ECC combination or GCb/Cis together with the HDAC inhibitor Valproic acid (VPA) to define whether EBV reactivation and subsequent antiviral treatment with Ganciclovir (GCV) could be used as virus-targeted therapy for EBVaGC. Drug combinations with VPA and GCV were evaluated in multiple cell lines and in an EBVaGC mouse model based on human naturally EBV-infected SNU-719 cells. Results: EBV reactivation was demonstrated by lytic mRNA transcripts and proteins in treated cells, and the virus-reactivating capacity of different CLVA drug combinations was compared in C666.1, AGS-BX1 and SNU-719 cell lines. In an EBVaGC mouse model, GCb/Cis with VPA and GCV strongly reduced tumor volume and showed the highest potential for EBV-reactivation. Upon a single round of CLVA treatment, EBV DNA levels in circulation decreased, and loss of EBV-positive cells in treated tumors was observed. In vivo EBV-reactivation was revealed by the presence of lytic gene transcripts and proteins in tumor tissues 6 days after treatment. Conclusion: In EBVaGC model systems, CLVA treatment showed a more potent virus reactivation and killing of tumor cells when compared to standard chemotherapy alone, suggesting that addition of VPA plus GCV to the ECC or GCb/Cis combination should be considered in future clinical studies.

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Establishment and characterization of six human gastric carcinoma cell lines, including one naturally infected with Epstein-Barr virus

Cellular Oncology ◽

10.1007/s13402-012-0073-9 ◽

2012 ◽

Vol 35 (2) ◽

pp. 127-136 ◽

Cited By ~ 17

Author(s):

Ja-Lok Ku ◽

Kyung-Hee Kim ◽

Jin-Sung Choi ◽

Sung-Hee Kim ◽

Young-Kyoung Shin ◽

...

Keyword(s):

Gastric Carcinoma ◽

Cell Lines ◽

Epstein Barr Virus ◽

Carcinoma Cell ◽

Gastric Carcinoma Cell ◽

Barr Virus ◽

Carcinoma Cell Lines ◽

Gastric Carcinoma Cell Lines ◽

Epstein Barr

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Comprehensive Multi-Omics Analysis Reveals Aberrant Metabolism of Epstein–Barr-Virus-Associated Gastric Carcinoma

Cells ◽

10.3390/cells8101220 ◽

2019 ◽

Vol 8 (10) ◽

pp. 1220 ◽

Cited By ~ 5

Author(s):

Yoon ◽

Kim ◽

Long ◽

Min ◽

Kim ◽

...

Keyword(s):

Gastric Cancer ◽

Gastric Carcinoma ◽

Epstein Barr Virus ◽

Tissue Samples ◽

Barr Virus ◽

Advanced Gastric Carcinoma ◽

Metabolic Genes ◽

Epithelial Cell Lines ◽

Epstein Barr ◽

Gastric Cancer Patients

The metabolic landscape of Epstein–Barr-virus-associated gastric cancer (EBVaGC) remains to be elucidated. In this study, we used transcriptomics, metabolomics, and lipidomics to comprehensively investigate aberrant metabolism in EBVaGC. Specifically, we conducted gene expression analyses using microarray-based data from gastric adenocarcinoma epithelial cell lines and tissue samples from patients with clinically advanced gastric carcinoma. We also conducted complementary metabolomics and lipidomics using various mass spectrometry platforms. We found a significant downregulation of genes related to metabolic pathways, especially the metabolism of amino acids, lipids, and carbohydrates. The effect of dysregulated metabolic genes was confirmed in a survival analysis of 3951 gastric cancer patients. We found 57 upregulated metabolites and 31 metabolites that were downregulated in EBVaGC compared with EBV-negative gastric cancer. Sixty-nine lipids, mainly ether-linked phospholipids and triacylglycerols, were downregulated, whereas 45 lipids, mainly phospholipids, were upregulated. In total, 15 metabolisms related to polar metabolites and 15 lipid-associated pathways were involved in alteration of metabolites by EBV in gastric cancer. In this work, we have described the metabolic landscape of EBVaGC at the multi-omics level. These findings could help elucidate the mechanism of EBVaGC oncogenesis.

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