1
|
Sobhi Amjad Z, Shojaeian A, Sadri Nahand J, Bayat M, Taghizadieh M, Rostamian M, Babaei F, Moghoofei M. Oncoviruses: Induction of cancer development and metastasis by increasing anoikis resistance. Heliyon 2023; 9:e22598. [PMID: 38144298 PMCID: PMC10746446 DOI: 10.1016/j.heliyon.2023.e22598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 11/07/2023] [Accepted: 11/15/2023] [Indexed: 12/26/2023] Open
Abstract
The phenomenon of cell death is a vital aspect in the regulation of aberrant cells such as cancer cells. Anoikis is a kind of cell death that occurs when cells get separated from the extracellular matrix. Some cancer cells can inhibit anoikis in order to progress metastasis. One of the key variables that might be implicated in anoikis resistance (AR) is viral infections. The most important viruses involved in this process are Epstein-Barr virus, human papillomavirus, hepatitis B virus, human herpes virus 8, human T-cell lymphotropic virus type 1, and hepatitis C virus. A better understanding of how carcinogenic viruses suppress anoikis might be helpful in developing an effective treatment for virus-associated cancers. In the current study, we review the role of the mentioned viruses and their gene products in anoikis inhibition.
Collapse
Affiliation(s)
- Zahra Sobhi Amjad
- Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Ali Shojaeian
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Javid Sadri Nahand
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mobina Bayat
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Taghizadieh
- Department of Pathology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mosayeb Rostamian
- Nosocomial Infections Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Farhad Babaei
- Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Mohsen Moghoofei
- Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
- Infectious Diseases Research Center, Health Research Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| |
Collapse
|
2
|
Liu W, Zhang Q, Zhang Y, Sun L, Xiao H, Luo B. Epstein-Barr Virus Regulates Endothelin-1 Expression through the ERK/FOXO1 Pathway in EBV-Associated Gastric Cancer. Microbiol Spectr 2023; 11:e0089822. [PMID: 36475746 PMCID: PMC9927292 DOI: 10.1128/spectrum.00898-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 11/11/2022] [Indexed: 12/13/2022] Open
Abstract
Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is one of the four subtypes of gastric carcinoma and its unique clinicopathological mechanism is unclear. Herein, the expression of endothelin-1 (ET-1) in EBVaGC was lower than of Epstein-Barr virus-negative gastric carcinoma (EBVnGC) and associated with a low frequency of lymph node metastasis of EBVaGC. Functional studies showed that the activation of ET-1/endothelin receptor type A (ETAR) axis could promote cell growth, migration, and antiapoptosis. The expression of the ET-1 gene was unrelated to methylation of its promoter region and miRNAs (-1, -125a, -125b). After being treated with MEK1/2 inhibitor (PD0325901), the inactivation of ERK1/2 pathway resulted in downregulation of ET-1 and forkhead box O1 (FOXO1) expression. Further, FOXO1 knockdown decreased the ET-1 expression. These findings indicated that ET-1 could be involved in development of gastric cancer and EBV could suppress the expression of ET-1 via the regulation of the transcription factor FOXO1 through the MAPK/ERK pathway. IMPORTANCE The relationship between Epstein-Barr virus and gastric cancer has been relatively clear. However, there are still many unresolved mechanisms of the virus in tumorigenesis. In recent years, activation of the endothelin-1 signaling axis has been found to play an important role in tumorigenesis, which is involved in tumor angiogenesis and epithelial-mesenchymal transition. EBV genes. In our study, we found that ET-1 was low-expressed in EBV-positive gastric cancer cells, which was due to the inhibition of ERK signaling by EBNA1 through the repression of FOXO1 expression. The low expression of ET-1 limits the proliferation, migration, and anti-apoptotic ability of tumor cells. These findings contribute to further understanding of the role of EBV in EBV-associated gastric cancer.
Collapse
Affiliation(s)
- Wen Liu
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Qianqian Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Yan Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
- Department of Clinical Laboratory, Central Hospital of Zibo, Zibo, China
| | - Lingling Sun
- Department of Pathology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Hua Xiao
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Bing Luo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, Qingdao, China
| |
Collapse
|
3
|
The Isolation and Full-Length Transcriptome Sequencing of a Novel Nidovirus and Response of Its Infection in Japanese Flounder (Paralichthys olivaceus). Viruses 2022; 14:v14061216. [PMID: 35746687 PMCID: PMC9230003 DOI: 10.3390/v14061216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/26/2022] [Accepted: 05/31/2022] [Indexed: 02/01/2023] Open
Abstract
A novel nidovirus, CSBV Bces-Po19, was isolated from the marine fish, Japanese flounder (Paralichthys olivaceus). The viral genome was 26,597 nucleotides long and shared 98.62% nucleotide identity with CSBV WHQSR4345. PacBio Sequel and Illumina sequencing were used to perform full-length transcriptome sequencing on CSBV Bces-Po19-sensitive (S) and -resistant (R) Japanese flounder. The results of negative staining revealed bacilliform and spherical virions. There were in total 1444 different genes between CSBV Bces-Po19 S and R groups, with 935 being up-regulated and 513 being down-regulated. Metabolism-, immune-, and RNA-related pathways were significantly enriched. Furthermore, CSBV Bces-Po19 infection induced alternative splicing (AS) events in Japanese flounder; the S group had a higher numbers of AS events (12,352) than the R group (11,452). The number of long non-coding RNA (lncRNA) in the S group, on the other hand, was significantly lower than in the R group. In addition to providing valuable information that sheds more light on CSBV Bces-Po19 infection, these research findings provide further clues for CSBV Bces-Po19 prevention and treatment.
Collapse
|
4
|
Wen Y, Xu H, Han J, Jin R, Chen H. How Does Epstein–Barr Virus Interact With Other Microbiomes in EBV-Driven Cancers? Front Cell Infect Microbiol 2022; 12:852066. [PMID: 35281433 PMCID: PMC8904896 DOI: 10.3389/fcimb.2022.852066] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 01/28/2022] [Indexed: 12/12/2022] Open
Abstract
The commensal microbiome refers to a large spectrum of microorganisms which mainly consists of viruses and bacteria, as well as some other components such as protozoa and fungi. Epstein–Barr virus (EBV) is considered as a common component of the human commensal microbiome due to its spread worldwide in about 95% of the adult population. As the first oncogenic virus recognized in human, numerous studies have reported the involvement of other components of the commensal microbiome in the increasing incidence of EBV-driven cancers. Additionally, recent advances have also defined the involvement of host–microbiota interactions in the regulation of the host immune system in EBV-driven cancers as well as other circumstances. The regulation of the host immune system by the commensal microbiome coinfects with EBV could be the implications for how we understand the persistence and reactivation of EBV, as well as the progression of EBV-associated cancers, since majority of the EBV persist as asymptomatic carrier. In this review, we attempt to summarize the possible mechanisms for EBV latency, reactivation, and EBV-driven tumorigenesis, as well as casting light on the role of other components of the microbiome in EBV infection and reactivation. Besides, whether novel microbiome targeting strategies could be applied for curing of EBV-driven cancer is discussed as well.
Collapse
Affiliation(s)
| | | | | | - Runming Jin
- *Correspondence: Hongbo Chen, ; Runming Jin,
| | - Hongbo Chen
- *Correspondence: Hongbo Chen, ; Runming Jin,
| |
Collapse
|
5
|
The Central Role of the Ubiquitin-Proteasome System in EBV-Mediated Oncogenesis. Cancers (Basel) 2022; 14:cancers14030611. [PMID: 35158879 PMCID: PMC8833352 DOI: 10.3390/cancers14030611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/19/2022] [Accepted: 01/24/2022] [Indexed: 12/30/2022] Open
Abstract
Simple Summary Epstein–Barr virus (EBV) is the first discovered human tumor virus, which contributes to the oncogenesis of many human cancers. The ubiquitin–proteasome system is a key player during EBV-mediated oncogenesis and has been developed as a crucial therapeutic target for treatment. In this review, we briefly describe how EBV antigens can modulate the ubiquitin–proteasome system for targeted protein degradation and how they are regulated in the EBV life cycle to mediate oncogenesis. Additionally, the developed proteasome inhibitors are discussed for the treatment of EBV-associated cancers. Abstract Deregulation of the ubiquitin–proteasome system (UPS) plays a critical role in the development of numerous human cancers. Epstein–Barr virus (EBV), the first known human tumor virus, has evolved distinct molecular mechanisms to manipulate the ubiquitin–proteasome system, facilitate its successful infection, and drive opportunistic cancers. The interactions of EBV antigens with the ubiquitin–proteasome system can lead to oncogenesis through the targeting of cellular factors involved in proliferation. Recent studies highlight the central role of the ubiquitin–proteasome system in EBV infection. This review will summarize the versatile strategies in EBV-mediated oncogenesis that contribute to the development of specific therapeutic approaches to treat EBV-associated malignancies.
Collapse
|
6
|
Kato I, Zhang J, Sun J. Bacterial-Viral Interactions in Human Orodigestive and Female Genital Tract Cancers: A Summary of Epidemiologic and Laboratory Evidence. Cancers (Basel) 2022; 14:425. [PMID: 35053587 PMCID: PMC8773491 DOI: 10.3390/cancers14020425] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 02/04/2023] Open
Abstract
Infectious agents, including viruses, bacteria, fungi, and parasites, have been linked to pathogenesis of human cancers, whereas viruses and bacteria account for more than 99% of infection associated cancers. The human microbiome consists of not only bacteria, but also viruses and fungi. The microbiome co-residing in specific anatomic niches may modulate oncologic potentials of infectious agents in carcinogenesis. In this review, we focused on interactions between viruses and bacteria for cancers arising from the orodigestive tract and the female genital tract. We examined the interactions of these two different biological entities in the context of human carcinogenesis in the following three fashions: (1) direct interactions, (2) indirect interactions, and (3) no interaction between the two groups, but both acting on the same host carcinogenic pathways, yielding synergistic or additive effects in human cancers, e.g., head and neck cancer, liver cancer, colon cancer, gastric cancer, and cervical cancer. We discuss the progress in the current literature and summarize the mechanisms of host-viral-bacterial interactions in various human cancers. Our goal was to evaluate existing evidence and identify gaps in the knowledge for future directions in infection and cancer.
Collapse
Affiliation(s)
- Ikuko Kato
- Department of Oncology and Pathology, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Jilei Zhang
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, IL 60612, USA;
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Jun Sun
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Illinois at Chicago, Chicago, IL 60612, USA;
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612, USA
- UIC Cancer Center, University of Illinois at Chicago, Chicago, IL 60612, USA
- Jesse Brown VA Medical Center, Chicago, IL 60612, USA
| |
Collapse
|
7
|
Ose N, Kawagishi S, Funaki S, Kanou T, Fukui E, Kimura K, Minami M, Shintani Y. Thymic Lymphoepithelial Carcinoma Associated with Epstein-Barr Virus: Experiences and Literature Review. Cancers (Basel) 2021; 13:4794. [PMID: 34638279 PMCID: PMC8507618 DOI: 10.3390/cancers13194794] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/07/2021] [Accepted: 09/23/2021] [Indexed: 12/13/2022] Open
Abstract
Thymic lymphoepithelial carcinoma (TLEC) is a primary thymic carcinoma that accounts for about 14% of all thymic epithelial tumors and is classified into 14 types. The histological morphology is similar to lymphoepithelioma, a type of undifferentiated nasopharyngeal carcinoma. It has been reported that squamous carcinoma accounts for approximately 80% of thymic carcinoma, followed by TLEC, which accounts for 6%. TLEC has been reported to be associated with Epstein-Barr virus (EBV), with EBV infection in TLEC tumor cells first noted by Lyvraz et al. in 1985. Tumors shown to be EBV-positive are classified as TLEC if lymphoplasmacytic infiltration is lacking. However, only about 50% of the cases are positive for EBV, which is lower compared to nasopharyngeal lymphoepithelioma. Instances of EBV infection in other types of thymic epithelial tumor have been reported at lower rates, which suggests that EBV infection may have an important influence on the carcinogenesis of TLEC, though the etiology is unknown. TLEC is a highly malignant tumor with poor prognosis, as affected patients have a median survival time of 22 months, according to 58 cases from the literature, while the 5-year survival rate is 34.4%. Presently, prognosis is not considered to be affected by the presence or absence of EBV positivity.
Collapse
Affiliation(s)
- Naoko Ose
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| | - Sachi Kawagishi
- Department of General Thoracic Surgery, Osaka International Cancer Institute, Chuo-ku, Osaka-shi 541-8567, Osaka, Japan;
| | - Soichiro Funaki
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| | - Takashi Kanou
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| | - Eriko Fukui
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| | - Kenji Kimura
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| | - Masato Minami
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| | - Yasushi Shintani
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Suita-shi 565-0871, Osaka, Japan; (S.F.); (T.K.); (E.F.); (K.K.); (M.M.); (Y.S.)
| |
Collapse
|
8
|
Jiang Y, Xiao H, Sun L, Zhang Y, Liu S, Luo B. LMP2A suppresses the role of AHR pathway through ERK signal pathway in EBV-associated gastric cancer. Virus Res 2021; 297:198399. [PMID: 33753181 DOI: 10.1016/j.virusres.2021.198399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 03/12/2021] [Accepted: 03/16/2021] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To investigate the function of the aryl hydrocarbon receptor (AHR) pathway in Epstein-Barr Virus (EBV)-associated gastric cancer (EBVaGC) and to explore the relationship between EBV and AHR expression. METHODS The expression of AHR in EBVaGC and EBV negative GC (EBVnGC) tissues was detected by immunohistochemistry (IHC). Real-time qPCR (RT-qPCR) and Western blot analysis were used to examine the expression of AHR, cytochrome P450 1A1 (CYP1A1), and cytochrome P450 1B1 (CYP1B1) in gastric cancer cells. The cell proliferation and migration assay were tested by CCK8 and transwell analysis. EBV-encoded latent membrane protein 2A (LMP2A) was over-expressed in SGC7901 cells and silenced in AGS-EBV cells to further identify its role in EBV positive GC cells. RESULTS It was found that EBV infection inhibited the expression of AHR in gastric cancer tissues and cell lines. We also found that the activation of AHR pathway can promote cell proliferation and migration. However, the function was restricted in EBVaGC cell lines compared with EBVnGC. LMP2A can suppress AHR expression and pathway activation by activating phosphorylation of extracellular signal-regulated kinase (ERK) in EBV positive GC cell lines. CONCLUSION EBV-encoded LMP2A regulated the function of the AHR pathway by activating the ERK signal pathway in EBV positive GC cell lines.
Collapse
Affiliation(s)
- Yuanyuan Jiang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, 308 Ningxia Road, Qingdao, 266021, China; Department of Medical Affairs of the Affiliated Hospital of Qingdao University, No. 1677 Wutaishan Road, Qingdao, 266000, China
| | - Hua Xiao
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, 308 Ningxia Road, Qingdao, 266021, China
| | - Lingling Sun
- Department of Pathology, The Affiliated Hospital of Qingdao University, 16 Jiangsu Road, Qingdao, 266003, China
| | - Yan Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, 308 Ningxia Road, Qingdao, 266021, China; Department of Clinical Laboratory, Central Hospital of Zibo, 19 Gongqingtuan Road, ZiBo, 255036, China
| | - Shuzhen Liu
- Department of Medical Affairs of the Affiliated Hospital of Qingdao University, No. 1677 Wutaishan Road, Qingdao, 266000, China.
| | - Bing Luo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, 308 Ningxia Road, Qingdao, 266021, China
| |
Collapse
|
9
|
Role of Epstein-Barr Virus C Promoter Deletion in Diffuse Large B Cell Lymphoma. Cancers (Basel) 2021; 13:cancers13030561. [PMID: 33535665 PMCID: PMC7867172 DOI: 10.3390/cancers13030561] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/19/2021] [Accepted: 01/27/2021] [Indexed: 12/14/2022] Open
Abstract
Simple Summary The C promoter of Epstein–Barr virus is assumed to be important for B cell growth and transformation. However, we present evidence that promoter activity is not only unneeded for transformation but also that absence of the promoter increased the transformation activity of the virus. We found that the C promoter was lost in some Epstein–Barr virus-associated lymphoma specimens. Therefore, deletion of the promoter could partially account for the tumorigenesis of Epstein–Barr virus-associated lymphomas. Abstract The Epstein–Barr virus (EBV) is the cause of several malignancies, including diffuse large B cell lymphoma (DLBCL). We recently found that EBV genomes in EBV-positive cancer specimens have various deletions (Okuno et al. Nat Microbiol. 2019). Here, we focus on the deletion of C promoter (Cp), which transcribes EBV nuclear antigen (EBNA) genes in type III latency. The Cp deletion found in a DLBCL patient (332 bp) was introduced into EBV-BAC of the B95-8 strain. Interestingly, the dCp virus transformed B cells more efficiently than WT and revertant strains. Deletion of Cp also promoted tumor formation and severe pathogenicity in a mouse xenograft model. RNA sequencing and qRT–PCR analyses revealed that Cp transcription was undetectable in the dCp cells. Instead, transcription from the W promoter (Wp), an alternative promoter for EBNA, was activated in the dCp mutant. We also found that the expression of latent membrane protein 2A (LMP2A) was somehow induced in the dCp mutant. Double knockout of Cp and LMP2A indicated that LMP2A is crucial for B cell transformation, but the increased transformation induced by Cp deletion cannot be explained by LMP2A alone. We also tested the effect of an anti-apoptotic viral BCL2 homolog, BHRF1, because its expression was reportedly induced more efficiently by that of Wp. However, increased growth transformation via Cp deletion was not due to the BHRF1 gene. Taken together, the results indicated that deletion of a specific region in Cp increased in vitro transformation and the rate of progression of EBV-positive lymphoproliferative disorders in vivo. Our data suggest that genomic alteration not only of the host but also the virus promotes EBV-positive tumor generation and expansion, although the molecular mechanism underlying this phenomenon is still unclear. However, LMP2A and BHRF1 are not involved.
Collapse
|
10
|
Miliotis CN, Slack FJ. Multi-layered control of PD-L1 expression in Epstein-Barr virus-associated gastric cancer. ACTA ACUST UNITED AC 2020; 6. [PMID: 34212113 PMCID: PMC8244904 DOI: 10.20517/2394-4722.2020.12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gastric cancer (GC) is the fifth most common cancer worldwide. In approximately 10% of GC cases, cancer cells show ubiquitous and monoclonal Epstein-Barr virus (EBV) infection. A significant feature of EBV-associated GC (EBVaGC) is high lymphocytic infiltration and high expression of immune checkpoint proteins, including programmed death-ligand 1 (PD-L1). This highlights EBVaGC as a strong candidate for immune checkpoint blockade therapy. Indeed, several recent studies have shown that EBV positivity in GC correlates with positive response to programmed cell death protein 1 (PD-1)/PD-L1 blockade therapy. Understanding the mechanisms that control PD-L1 expression in EBVaGC can indicate new predictive biomarkers for immunotherapy, as well as therapeutic targets for combination therapy. Various mechanisms have been implicated in PD-L1 expression regulation, including structural variations, post-transcriptional control, oncogenic activation of intrinsic signaling pathways, and increased sensitivity to extrinsic signals. This review provides the most recent updates on the multilayered control of PD-L1 expression in EBVaGC.
Collapse
Affiliation(s)
- Christos N Miliotis
- HMS Initiative for RNA Medicine, Department of Pathology, Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Frank J Slack
- HMS Initiative for RNA Medicine, Department of Pathology, Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
11
|
Buehler J, Carpenter E, Zeltzer S, Igarashi S, Rak M, Mikell I, Nelson JA, Goodrum F. Host signaling and EGR1 transcriptional control of human cytomegalovirus replication and latency. PLoS Pathog 2019; 15:e1008037. [PMID: 31725811 PMCID: PMC6855412 DOI: 10.1371/journal.ppat.1008037] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 08/21/2019] [Indexed: 12/15/2022] Open
Abstract
Sustained phosphotinositide3-kinase (PI3K) signaling is critical to the maintenance of alpha and beta herpesvirus latency. We have previously shown that the beta-herpesvirus, human cytomegalovirus (CMV), regulates epidermal growth factor receptor (EGFR), upstream of PI3K, to control states of latency and reactivation. How signaling downstream of EGFR is regulated and how this impacts CMV infection and latency is not fully understood. We demonstrate that CMV downregulates EGFR early in the productive infection, which blunts the activation of EGFR and its downstream pathways in response to stimuli. However, CMV infection sustains basal levels of EGFR and downstream pathway activity in the context of latency in CD34+ hematopoietic progenitor cells (HPCs). Inhibition of MEK/ERK, STAT or PI3K/AKT pathways downstream of EGFR increases viral reactivation from latently infected CD34+ HPCs, defining a role for these pathways in latency. We hypothesized that CMV modulation of EGFR signaling might impact viral transcription important to latency. Indeed, EGF-stimulation increased expression of the UL138 latency gene, but not immediate early or early viral genes, suggesting that EGFR signaling promotes latent gene expression. The early growth response-1 (EGR1) transcription factor is induced downstream of EGFR signaling through the MEK/ERK pathway and is important for the maintenance of hematopoietic stemness. We demonstrate that EGR1 binds the viral genome upstream of UL138 and is sufficient to promote UL138 expression. Further, disruption of EGR1 binding upstream of UL138 prevents the establishment of latency in CD34+ HPCs. Our results indicate a model whereby UL138 modulation of EGFR signaling feeds back to promote UL138 gene expression and suppression of replication for latency. By this mechanism, the virus has hardwired itself into host cell biology to sense and respond to changes in homeostatic host cell signaling. Host signaling is important for regulating states of cytomegalovirus (CMV) replication and latency. We have shown that human cytomegalovirus regulates EGFR levels and trafficking and that sustained EGFR or downstream PI3K signaling is a requirement for viral latency. Changes in host signaling have the ability to alter viral and host gene expression to impact the outcome of infection. Here we show that EGFR signaling through MEK/ERK pathway induces the host EGR1 transcription factor that is highly expressed in hematopoietic stem cells and necessary for the maintenance of hematopoietic stemness. Downregulation of EGR1 promotes stem cell mobilization and differentiation, known stimuli for CMV reactivation. We identified functional EGR1 binding sites upstream of the UL138 CMV latency gene and EGR1 stimulated UL138 expression to reinforce the latent infection. Mutant viruses where the regulation of UL138 by EGR1 is disrupted are unable to establish latency in CD34+ HPCs. This study advances our understanding of how host signaling impacts decisions to enter into or exit from latency. The regulation of viral gene expression by host signaling allows the virus to sense and respond to changes in host stress or differentiation.
Collapse
Affiliation(s)
- Jason Buehler
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Ethan Carpenter
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Sebastian Zeltzer
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Suzu Igarashi
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Michael Rak
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Iliyana Mikell
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, United States of America
| | - Jay A. Nelson
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, United States of America
| | - Felicia Goodrum
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
- * E-mail:
| |
Collapse
|
12
|
LMP2A induces DNA methylation and expression repression of AQP3 in EBV-associated gastric carcinoma. Virology 2019; 534:87-95. [PMID: 31220652 DOI: 10.1016/j.virol.2019.06.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 05/14/2019] [Accepted: 06/11/2019] [Indexed: 12/27/2022]
Abstract
Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) is a unique type of gastric carcinomas that promoter hypermethylation of tumor-related genes is extremely frequent to be found. Aquaporin 3 (AQP3) is a small membrane transport protein that plays a crucial role in cancer progression and metastasis. However, there is no experimental study on the expression of AQP3 in EBVaGC and the regulation mechanism of EBV on AQP3. In this study, the loss of AQP3 was contributed by the hypermethylation status of AQP3 promoter in EBVaGC which was caused by elevated expression of DNMT3a. In addition, stable and transient transfection system in SGC7901 showed that viral latent membrane protein 2A (LMP2A) activated phosphorylated ERK and up-regulated DNMT3a. Taken together, LMP2A induced the phosphorylation of ERK, which activated DNMT3a transcription and caused AQP3 expression loss through CpG island methylation of AQP3 promoter in EBVaGC.
Collapse
|
13
|
Modified Anoikis Assay That Functionally Segregates Epstein-Barr Virus LMP1 Strains into Two Groups. J Virol 2018; 92:JVI.00557-18. [PMID: 29950426 DOI: 10.1128/jvi.00557-18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/21/2018] [Indexed: 12/28/2022] Open
Abstract
Nasopharyngeal carcinoma (NPC) is a metastatic Epstein-Barr virus (EBV)-associated cancer that expresses the viral oncogenic protein, latent membrane protein 1 (LMP1). During epithelial metastasis, detached cells must overcome anoikis-induced cell death and gain the ability to reattach and restore growth potential. Anoikis assays have revealed cell survival mechanisms during suspension, but few studies have tracked the fate of cells surviving anoikis-inducing conditions. In this study, a modified anoikis assay was used to examine if the expression of LMP1 confers the recovery of epithelial cells from anoikis. Cells expressing LMP1 mutants and strains were evaluated for distinguishing properties in survival during suspension, reattachment, and outgrowth potential. Expression of LMP1 promoted the outgrowth of the NPC cell line HK1 following anoikis induction that was not attributed to enhanced cell survival in suspension or reattachment. The mechanism of LMP1-induced outgrowth required Akt signaling and the conserved PXQXT motif on LMP1, which activates Akt. Deletion of any of the three LMP1 C-terminal activation regions (CTAR) abrogated anoikis recovery, suggesting that additional LMP1-regulated signaling pathways are likely involved. Of the seven LMP1 strains, only B958, China1, and Med+ promoted HK1 outgrowth from anoikis. This distinguishing biological property segregates LMP1 strains into two categories (anoikis recovering and nonrecovering) and suggests that LMP1 strain-specific sequences may be important in determining metastatic outgrowth potential in NPC tumors.IMPORTANCE LMP1 is one of the most divergent sequences in the EBV genome and phylogenetically segregates into seven LMP1 strains. The LMP1 strains differ in geographical distribution and NPC tumor prevalence, but the molecular basis for this potential selection is not clear. While there are signaling motifs conserved in all LMP1 sequences from circulating EBV isolates, phylogenetic studies of NPC also suggest that there may be sequence selection for tumor-associated LMP1 strains and polymorphisms. The present study describes a modified anoikis assay that can distinguish LMP1 strains into two groups by biological properties. The pleiotropic LMP1 signaling properties and sequence diversity may offer a unique opportunity to illuminate the complex mechanisms of metastasis. Although the host genomic landscape is variable between NPC tumors, the present functional-mapping studies on LMP1 support the notion that viral proteins could serve as molecular tool kits and potentially reveal sequence-associated risk factors in NPC metastatic progression.
Collapse
|
14
|
Romero-Masters JC, Ohashi M, Djavadian R, Eichelberg MR, Hayes M, Bristol JA, Ma S, Ranheim EA, Gumperz J, Johannsen EC, Kenney SC. An EBNA3C-deleted Epstein-Barr virus (EBV) mutant causes B-cell lymphomas with delayed onset in a cord blood-humanized mouse model. PLoS Pathog 2018; 14:e1007221. [PMID: 30125329 PMCID: PMC6117096 DOI: 10.1371/journal.ppat.1007221] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 08/30/2018] [Accepted: 07/16/2018] [Indexed: 12/15/2022] Open
Abstract
EBV causes human B-cell lymphomas and transforms B cells in vitro. EBNA3C, an EBV protein expressed in latently-infected cells, is required for EBV transformation of B cells in vitro. While EBNA3C undoubtedly plays a key role in allowing EBV to successfully infect B cells, many EBV+ lymphomas do not express this protein, suggesting that cellular mutations and/or signaling pathways may obviate the need for EBNA3C in vivo under certain conditions. EBNA3C collaborates with EBNA3A to repress expression of the CDKN2A-encoded tumor suppressors, p16 and p14, and EBNA3C-deleted EBV transforms B cells containing a p16 germline mutation in vitro. Here we have examined the phenotype of an EBNAC-deleted virus (Δ3C EBV) in a cord blood-humanized mouse model (CBH). We found that the Δ3C virus induced fewer lymphomas (occurring with a delayed onset) in comparison to the wild-type (WT) control virus, although a subset (10/26) of Δ3C-infected CBH mice eventually developed invasive diffuse large B cell lymphomas with type III latency. Both WT and Δ3C viruses induced B-cell lymphomas with restricted B-cell populations and heterogeneous T-cell infiltration. In comparison to WT-infected tumors, Δ3C-infected tumors had greatly increased p16 levels, and RNA-seq analysis revealed a decrease in E2F target gene expression. However, we found that Δ3C-infected tumors expressed c-Myc and cyclin E at similar levels compared to WT-infected tumors, allowing cells to at least partially bypass p16-mediated cell cycle inhibition. The anti-apoptotic proteins, BCL2 and IRF4, were expressed in Δ3C-infected tumors, likely helping cells avoid c-Myc-induced apoptosis. Unexpectedly, Δ3C-infected tumors had increased T-cell infiltration, increased expression of T-cell chemokines (CCL5, CCL20 and CCL22) and enhanced type I interferon response in comparison to WT tumors. Together, these results reveal that EBNA3C contributes to, but is not essential for, EBV-induced lymphomagenesis in CBH mice, and suggest potentially important immunologic roles of EBNA3C in vivo.
Collapse
MESH Headings
- Animals
- Cell Transformation, Viral/genetics
- Cells, Cultured
- Disease Models, Animal
- Epstein-Barr Virus Infections/complications
- Epstein-Barr Virus Infections/genetics
- Epstein-Barr Virus Nuclear Antigens/genetics
- Fetal Blood/immunology
- HEK293 Cells
- Herpesvirus 4, Human/genetics
- Herpesvirus 4, Human/physiology
- Humans
- Lymphoma, B-Cell/immunology
- Lymphoma, B-Cell/pathology
- Lymphoma, B-Cell/virology
- Mice
- Mice, Inbred NOD
- Mice, Transgenic
- Virus Latency/genetics
Collapse
Affiliation(s)
- James C. Romero-Masters
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Makoto Ohashi
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Reza Djavadian
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Mark R. Eichelberg
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Mitch Hayes
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jillian A. Bristol
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Shidong Ma
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Erik A. Ranheim
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Jenny Gumperz
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Eric C. Johannsen
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Shannon C. Kenney
- Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| |
Collapse
|
15
|
Jin S, Cheng T, Guo Y, Lin P, Zhao P, Liu C, Kusakabe T, Xia Q. Bombyx mori epidermal growth factor receptor is required for nucleopolyhedrovirus replication. INSECT MOLECULAR BIOLOGY 2018; 27:464-477. [PMID: 29603500 DOI: 10.1111/imb.12386] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Baculovirus-host interactions are important models for studying the biological control of lepidopteran pests. Research on baculovirus-host interactions has focussed on baculovirus manipulation of cellular signalling pathways, including the extracellular signal-regulated kinase (ERK) and phosphatidylinositol-3-kinases/protein kinase B (PI3K/Akt) signalling pathways. However, the mechanism underlying ERK and PI3K/Akt activation and function in response to baculovirus infection remains poorly understood. Here, we demonstrated that baculovirus activated the Bombyx mori ERK and PI3K/Akt signalling pathways via the B. mori epidermal growth factor receptor (BmEGFR). To further characterize the function of the BmEGFR/ERK signalling pathway in baculovirus replication, we calculated genome-wide changes in kinase-chromatin interactions for ERK after baculovirus infection using chromatin immunoprecipitation followed by high-throughput sequencing. A Gene Ontology analysis showed that virus infection had effects on the biological regulation, cellular process and metabolic process pathways. Moreover, ERK was shown to regulate the transcription of late viral genes. Taken together, our results suggest that baculoviruses manipulate components of the host cell machinery for replication via modulation of the BmEGFR signalling pathway.
Collapse
Affiliation(s)
- S Jin
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - T Cheng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Y Guo
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - P Lin
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - P Zhao
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - C Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing, China
| | - T Kusakabe
- Laboratory of Silkworm Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Hakozaki, Fukuoka, Japan
| | - Q Xia
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Chongqing Engineering and Technology Research Center for Novel Silk Materials, Chongqing, China
| |
Collapse
|
16
|
Tsao SW, Tsang CM, Lo KW. Epstein-Barr virus infection and nasopharyngeal carcinoma. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0270. [PMID: 28893937 DOI: 10.1098/rstb.2016.0270] [Citation(s) in RCA: 350] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2017] [Indexed: 12/24/2022] Open
Abstract
Epstein-Barr virus (EBV) is associated with multiple types of human cancer, including lymphoid and epithelial cancers. The closest association with EBV infection is seen in undifferentiated nasopharyngeal carcinoma (NPC), which is endemic in the southern Chinese population. A strong association between NPC risk and the HLA locus at chromosome 6p has been identified, indicating a link between the presentation of EBV antigens to host immune cells and NPC risk. EBV infection in NPC is clonal in origin, strongly suggesting that NPC develops from the clonal expansion of a single EBV-infected cell. In epithelial cells, the default program of EBV infection is lytic replication. However, latent infection is the predominant mode of EBV infection in NPC. The establishment of latent EBV infection in pre-invasive nasopharyngeal epithelium is believed to be an early stage of NPC pathogenesis. Recent genomic study of NPC has identified multiple somatic mutations in the upstream negative regulators of NF-κB signalling. Dysregulated NF-κB signalling may contribute to the establishment of latent EBV infection in NPC. Stable EBV infection and the expression of latent EBV genes are postulated to drive the transformation of pre-invasive nasopharyngeal epithelial cells to cancer cells through multiple pathways.This article is part of the themed issue 'Human oncogenic viruses'.
Collapse
Affiliation(s)
- Sai Wah Tsao
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Chi Man Tsang
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Kwok Wai Lo
- Department of Anatomical and Cellular Pathology and State Key Laboratory in Oncology in South China, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR
| |
Collapse
|
17
|
Lussignol M, Esclatine A. Herpesvirus and Autophagy: "All Right, Everybody Be Cool, This Is a Robbery!". Viruses 2017; 9:v9120372. [PMID: 29207540 PMCID: PMC5744147 DOI: 10.3390/v9120372] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/26/2017] [Accepted: 11/27/2017] [Indexed: 12/20/2022] Open
Abstract
Autophagy is an essential vacuolar process of the cell, leading to lysosomal degradation and recycling of proteins and organelles, which is extremely important in maintaining homeostasis. Multiple roles have been now associated with autophagy, in particular a pro-survival role in nutrient starvation or in stressful environments, a role in life span extension, in development, or in innate and adaptive immunity. This cellular process can also take over microorganisms or viral proteins inside autophagosomes and degrade them directly in autolysosomes and is then called xenophagy and virophagy, respectively. Several Herpesviruses have developed strategies to escape this degradation, by expression of specific anti-autophagic proteins. However, we are increasingly discovering that Herpesviruses hijack autophagy, rather than just fight it. This beneficial effect is obvious since inhibition of autophagy will lead to decreased viral titers for human cytomegalovirus (HCMV), Epstein-Barr virus (EBV) or Varicella-Zoster virus (VZV), for example. Conversely, autophagy stimulation will improve viral multiplication. The autophagic machinery can be used in whole or in part, and can optimize viral propagation or persistence. Some viruses block maturation of autophagosomes to avoid the degradation step, then autophagosomal membranes are used to contribute to the envelopment and/or the egress of viral particles. On the other hand, VZV stimulates the whole process of autophagy to subvert it in order to use vesicles containing ATG (autophagy-related) proteins and resembling amphisomes for their transport in the cytoplasm. During latency, autophagy can also be activated by latent proteins encoded by different oncogenic Herpesviruses to promote cell survival and achieve long term viral persistence in vivo. Finally, reactivation of gammaherpesvirus Murid Herpesvirus 68 (MHV68) in mice appears to be positively modulated by autophagy, in order to control the level of inflammation. Therefore, Herpesviruses appear to behave more like thieves than fugitives.
Collapse
Affiliation(s)
- Marion Lussignol
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
| | - Audrey Esclatine
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
| |
Collapse
|
18
|
Kakavandi E, Shahbahrami R, Goudarzi H, Eslami G, Faghihloo E. Anoikis resistance and oncoviruses. J Cell Biochem 2017; 119:2484-2491. [DOI: 10.1002/jcb.26363] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 08/15/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Ehsan Kakavandi
- Department of VirologySchool of Public HealthTehran University of Medical SciencesTehranIran
- Students’ Scientific Research CenterTehran University of Medical SciencesTehranIran
| | - Ramin Shahbahrami
- Department of VirologySchool of Public HealthTehran University of Medical SciencesTehranIran
| | - Hossein Goudarzi
- Department of MicrobiologySchool of MedicineShahid Beheshti University of Medical SciencesTehranIran
| | - Gita Eslami
- Department of MicrobiologySchool of MedicineShahid Beheshti University of Medical SciencesTehranIran
| | - Ebrahim Faghihloo
- Department of MicrobiologySchool of MedicineShahid Beheshti University of Medical SciencesTehranIran
| |
Collapse
|
19
|
Shahani T, Makvandi M, Samarbafzadeh A, Teimoori A, Ranjbar N, saki N, Nikakhlagh S, Neisi N, Hosseini Z, Pourrezaei S, Shabani A, Radmehr H, Mehravaran H, Kiani H, Haghi A. Frequency of Epstein Barr Virus Type 1 Among Nasopharyngeal Carcinomas in Iranian Patients. Asian Pac J Cancer Prev 2017; 18:327-331. [PMID: 28345327 PMCID: PMC5454723 DOI: 10.22034/apjcp.2017.18.2.327] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Background: Around 95% of the world’s population are infected with the Epstein-Barr virus (EBV), which can persist latent in B lymphocytes and epithelial cells life-long. EBV has been linked with lymphoid and epithelial cancers and persistence of EBV infection in lymphoid or epithelial cells may result in virus-associated B-cell tumors or nasopharyngeal carcinomas (NPC). This study was conducted to determine the frequency of EBV DNA in nasopharyngeal carcinoma tissue of Iranian patients. Materials and methods: A total of 50 blocks of formalin-fixed paraffin-embedded tissue of NPCs from 38 (76 %) male and 12 (24%) female patients were collected from archives of Ahvaz hospitals. Sections were cut at 5 μm and DNA was extracted for detection of EBV DNA and EBV typing by mested PCR. DNA sequencing was performed to confirm PCR results. The distribution of EBV DNA was compared among WHO histological subtypes of NPC. Results: Some 3 female and 11 (22%) male NPC samples showed positive for EBV DNA type 1, 2/14(22.2%)WHO histological type II and 12/41(29.3%) WHO histological type III. Conclusions: The frequency of EBV DNA among NPCs in Iranian patients was found to be 28%, EBV type I predominating. Both WHO histological type II and III NPC subtypes demonstrated approximately the same detection prevalence.
Collapse
Affiliation(s)
- Toran Shahani
- Health Research Institute, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Abstract
Latent Epstein–Barr virus (EBV) infection has a substantial role in causing many human disorders. The persistence of these viral genomes in all malignant cells, yet with the expression of limited latent genes, is consistent with the notion that EBV latent genes are important for malignant cell growth. While the EBV-encoded nuclear antigen-1 (EBNA-1) and latent membrane protein-2A (LMP-2A) are critical, the EBNA-leader proteins, EBNA-2, EBNA-3A, EBNA-3C and LMP-1, are individually essential for in vitro transformation of primary B cells to lymphoblastoid cell lines. EBV-encoded RNAs and EBNA-3Bs are dispensable. In this review, the roles of EBV latent genes are summarized.
Collapse
Affiliation(s)
- Myung-Soo Kang
- 1] Samsung Advanced Institute for Health Sciences and Technology (SAIHST), Samsung Medical Center, Sungkyunkwan University, Seoul, Korea [2] Samsung Biomedical Research Institute (SBRI), Samsung Medical Center, Sungkyunkwan University, Seoul, Korea
| | - Elliott Kieff
- Department of Medicine, Brigham and Women's Hospital, Program in Virology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
21
|
Higuchi M, Takahashi M, Tanaka Y, Fujii M. Downregulation of proapoptotic Bim augments IL-2-independent T-cell transformation by human T-cell leukemia virus type-1 Tax. Cancer Med 2014; 3:1605-14. [PMID: 25175936 PMCID: PMC4298387 DOI: 10.1002/cam4.329] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 07/26/2014] [Accepted: 08/05/2014] [Indexed: 12/18/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1), an etiological agent of adult T-cell leukemia, immortalizes and transforms primary human T cells in vitro in both an interleukin (IL)-2-dependent and IL-2-independent manner. Expression of the HTLV-1 oncoprotein Tax transforms the growth of the mouse T-cell line CTLL-2 from being IL-2-dependent to IL-2-independent. Withdrawal of IL-2 from normal activated T cells induces apoptosis, which is mediated through the inducible expression of several proapoptotic proteins, including Bim. In this study, we found that Tax protects IL-2-depleted T cells against Bim-induced apoptosis. Withdrawal of IL-2 from CTLL-2 cells induced a prominent increase in the level of Bim protein in CTLL-2 cells, but not in Tax-transformed CTLL-2 cells. This inhibition of Bim in Tax-transformed CTLL-2 cells was mediated by two mechanisms: downregulation of Bim mRNA and posttranscriptional reduction of Bim protein. Transient expression of Tax in CTLL-2 cells also inhibited IL-2 depletion–induced expression of Bim, however, this decrease in Bim protein expression was not due to downregulation of Bim mRNA, thus indicating that Bim mRNA downregulation in Tax-transformed CTLL-2 occurs only after long-term expression of Tax. Transient expression of Tax in CTLL-2 cells also induced Erk activation, however, this was not involved in the reduction of Bim protein. Knockdown of Bim expression in CTLL-2 cells augmented Tax-induced IL-2-independent transformation. HTLV-1 infection of human T cells also reduced their levels of Bim protein, and restoring Bim expression in HTLV-1-infected cells reduced their proliferation by inducing apoptosis. Taken together, these results indicate that Tax-induced downregulation of Bim in HTLV-1-infected T cells promotes their IL-2-independent growth, thereby supporting the persistence of HTLV-1 infection in vivo.
Collapse
Affiliation(s)
- Masaya Higuchi
- Division of Virology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | | | | | | |
Collapse
|
22
|
Brown CW, Brodsky AS, Freiman RN. Notch3 overexpression promotes anoikis resistance in epithelial ovarian cancer via upregulation of COL4A2. Mol Cancer Res 2014; 13:78-85. [PMID: 25169943 DOI: 10.1158/1541-7786.mcr-14-0334] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
UNLABELLED Ovarian cancer is a lethal disease with the majority of diagnosed women having distant metastases. Interestingly, although Notch3 overexpression has been correlated with poor survival in epithelial ovarian cancer (EOC), little is known about its mechanism of action. Data show that Notch3 specifically promotes anoikis resistance. In addition, data indicate a positive role for focal adhesion kinase (FAK) as well as downstream signaling kinases such as Akt and Erk 1/2 in promoting anchorage-independent growth. Mechanistically, both mRNA transcript and protein levels of type IV collagen (COL4A2) are reduced when Notch3 levels are decreased and exogenous collagen IV supplementation reverses the anoikis sensitivity. Reduction of COL4A2 expression by RNAI-mediated knockdown induces cell death. Finally, elevated Notch3 expression levels correlate with higher COL4A2 expression in human ovarian tumor specimens. IMPLICATIONS These data highlight type IV collagen as a novel therapeutic target for metastatic EOC. Visual Overview: http://mcr.aacrjournals.org/content/early/2014/11/25/1541-7786.MCR-14-0334/F1.large.jpg
Collapse
Affiliation(s)
- Caitlin W Brown
- Graduate Program in Pathobiology, Brown University, Providence, Rhode Island
| | - Alexander S Brodsky
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - Richard N Freiman
- Graduate Program in Pathobiology, Brown University, Providence, Rhode Island. Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island.
| |
Collapse
|
23
|
Abstract
Epstein-Barr virus (EBV), a ubiquitous human double stranded DNA virus, is associated with a variety of malignancies including Burkitt's lymphoma, Hodgkin's lymphoma, nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC). These EBV-associated cancers are characterized by the proliferation of monoclonal EBV-infected cells, and viral gene expression in these cells is limited to a subset of latent genes, indicating that EBV latent genes contribute to carcinogenesis. Here I describe the mechanisms of carcinogenesis by EBV, focusing on the function of two EBV latent gens, latent membrane protein 2A (LMP2A) and EBV-encoded small RNA (EBER). LMP2A, which is known to mimic the B cell receptor (BCR) signaling, has been reported to contribute to malignant lymphoma development through the modulation of immune signals. Also, it has been demonstrated that LMP2A-mediated intracellular signaling plays significant roles in epithelial carcinogenesis. On the other hand, it has been demonstrated that EBER, which is expected to form double stranded RNA (dsRNA) structure, triggers a signal transduction from host viral RNA sensors RIG-I and TLR3. Activation of innate immune signals by EBER has been reported to contribute to the pathogenesis of EBV-associated diseases, including cancers.
Collapse
Affiliation(s)
- Dai Iwakiri
- Institute for Genetic Medicine Hokkaido University
| |
Collapse
|
24
|
An ITAM in a nonenveloped virus regulates activation of NF-κB, induction of beta interferon, and viral spread. J Virol 2013; 88:2572-83. [PMID: 24352448 DOI: 10.1128/jvi.02573-13] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Immunoreceptor tyrosine-based activation motifs (ITAMs) are signaling domains located within the cytoplasmic tails of many transmembrane receptors and associated adaptor proteins that mediate immune cell activation. ITAMs also have been identified in the cytoplasmic tails of some enveloped virus glycoproteins. Here, we identified ITAM sequences in three mammalian reovirus proteins: μ2, σ2, and λ2. We demonstrate for the first time that μ2 is phosphorylated, contains a functional ITAM, and activates NF-κB. Specifically, μ2 and μNS recruit the ITAM-signaling intermediate Syk to cytoplasmic viral factories and this recruitment requires the μ2 ITAM. Moreover, both the μ2 ITAM and Syk are required for maximal μ2 activation of NF-κB. A mutant virus lacking the μ2 ITAM activates NF-κB less efficiently and induces lower levels of the downstream antiviral cytokine beta interferon (IFN-β) than does wild-type virus despite similar replication. Notably, the consequences of these μ2 ITAM effects are cell type specific. In fibroblasts where NF-κB is required for reovirus-induced apoptosis, the μ2 ITAM is advantageous for viral spread and enhances viral fitness. Conversely, in cardiac myocytes where the IFN response is critical for antiviral protection and NF-κB is not required for apoptosis, the μ2 ITAM stimulates cellular defense mechanisms and diminishes viral fitness. Together, these results suggest that the cell type-specific effect of the μ2 ITAM on viral spread reflects the cell type-specific effects of NF-κB and IFN-β. This first demonstration of a functional ITAM in a nonenveloped virus presents a new mechanism for viral ITAM-mediated signaling with likely organ-specific consequences in the host.
Collapse
|
25
|
Inhibition of Bim enhances replication of varicella-zoster virus and delays plaque formation in virus-infected cells. J Virol 2013; 88:1381-8. [PMID: 24227856 DOI: 10.1128/jvi.01695-13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Programmed cell death (apoptosis) is an important host defense mechanism against intracellular pathogens, such as viruses. Accordingly, viruses have evolved multiple mechanisms to modulate apoptosis to enhance replication. Varicella-zoster virus (VZV) induces apoptosis in human fibroblasts and melanoma cells. We found that VZV triggered the phosphorylation of the proapoptotic proteins Bim and BAD but had little or no effect on other Bcl-2 family members. Since phosphorylation of Bim and BAD reduces their proapoptotic activity, this may prevent or delay apoptosis in VZV-infected cells. Phosphorylation of Bim but not BAD in VZV-infected cells was dependent on activation of the MEK/extracellular signal-regulated kinase (ERK) pathway. Cells knocked down for Bim showed delayed VZV plaque formation, resulting in longer survival of VZV-infected cells and increased replication of virus, compared with wild-type cells infected with virus. Conversely, overexpression of Bim resulted in earlier plaque formation, smaller plaques, reduced virus replication, and increased caspase 3 activity. Inhibition of caspase activity in VZV-infected cells overexpressing Bim restored levels of virus production similar to those seen with virus-infected wild-type cells. Previously we showed that VZV ORF12 activates ERK and inhibits apoptosis in virus-infected cells. Here we found that VZV ORF12 contributes to Bim and BAD phosphorylation. In summary, VZV triggers Bim phosphorylation; reduction of Bim levels results in longer survival of VZV-infected cells and increased VZV replication.
Collapse
|