1
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Zhang D, Wu X, Xue X, Li W, Zhou P, Lv Z, Zhao K, Zhu F. Ancient dormant virus remnant ERVW-1 drives ferroptosis via degradation of GPX4 and SLC3A2 in schizophrenia. Virol Sin 2024; 39:31-43. [PMID: 37690733 PMCID: PMC10877354 DOI: 10.1016/j.virs.2023.09.001] [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: 05/04/2023] [Accepted: 09/06/2023] [Indexed: 09/12/2023] Open
Abstract
Human endogenous retroviruses (HERVs) are remnants of retroviral infections in human germline cells from millions of years ago. Among these, ERVW-1 (also known as HERV-W-ENV, ERVWE1, or ENVW) encodes the envelope protein of the HERV-W family, which contributes to the pathophysiology of schizophrenia. Additionally, neuropathological studies have revealed cell death and disruption of iron homeostasis in the brains of individuals with schizophrenia. Here, our bioinformatics analysis showed that differentially expressed genes in the human prefrontal cortex RNA microarray dataset (GSE53987) were mainly related to ferroptosis and its associated pathways. Clinical data demonstrated significantly lower expression levels of ferroptosis-related genes, particularly Glutathione peroxidase 4 (GPX4) and solute carrier family 3 member 2 (SLC3A2), in schizophrenia patients compared to normal controls. Further in-depth analyses revealed a significant negative correlation between ERVW-1 expression and the levels of GPX4/SLC3A2 in schizophrenia. Studies indicated that ERVW-1 increased iron levels, malondialdehyde (MDA), and transferrin receptor protein 1 (TFR1) expression while decreasing glutathione (GSH) levels and triggering the loss of mitochondrial membrane potential, suggesting that ERVW-1 can induce ferroptosis. Ongoing research has shown that ERVW-1 reduced the expression of GPX4 and SLC3A2 by inhibiting their promoter activities. Moreover, Ferrostatin-1 (Fer-1), the ferroptosis inhibitor, reversed the iron accumulation and mitochondrial membrane potential loss, as well as restored the expressions of ferroptosis markers GSH, MDA, and TFR1 induced by ERVW-1. In conclusion, ERVW-1 could promote ferroptosis by downregulating the expression of GPX4 and SLC3A2, revealing a novel mechanism by which ERVW-1 contributes to neuronal cell death in schizophrenia.
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Affiliation(s)
- Dongyan Zhang
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Xiulin Wu
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Xing Xue
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Wenshi Li
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Ping Zhou
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Zhao Lv
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Kexin Zhao
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Fan Zhu
- State Key Laboratory of Virology and Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China; Hubei Province Key Laboratory of Allergy & Immunology, Wuhan University, Wuhan, 430071, China.
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2
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Stricker E, Peckham-Gregory EC, Scheurer ME. HERVs and Cancer-A Comprehensive Review of the Relationship of Human Endogenous Retroviruses and Human Cancers. Biomedicines 2023; 11:936. [PMID: 36979914 PMCID: PMC10046157 DOI: 10.3390/biomedicines11030936] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/03/2023] [Accepted: 03/10/2023] [Indexed: 03/30/2023] Open
Abstract
Genomic instability and genetic mutations can lead to exhibition of several cancer hallmarks in affected cells such as sustained proliferative signaling, evasion of growth suppression, activated invasion, deregulation of cellular energetics, and avoidance of immune destruction. Similar biological changes have been observed to be a result of pathogenic viruses and, in some cases, have been linked to virus-induced cancers. Human endogenous retroviruses (HERVs), once external pathogens, now occupy more than 8% of the human genome, representing the merge of genomic and external factors. In this review, we outline all reported effects of HERVs on cancer development and discuss the HERV targets most suitable for cancer treatments as well as ongoing clinical trials for HERV-targeting drugs. We reviewed all currently available reports of the effects of HERVs on human cancers including solid tumors, lymphomas, and leukemias. Our review highlights the central roles of HERV genes, such as gag, env, pol, np9, and rec in immune regulation, checkpoint blockade, cell differentiation, cell fusion, proliferation, metastasis, and cell transformation. In addition, we summarize the involvement of HERV long terminal repeat (LTR) regions in transcriptional regulation, creation of fusion proteins, expression of long non-coding RNAs (lncRNAs), and promotion of genome instability through recombination.
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Affiliation(s)
- Erik Stricker
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77047, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77047, USA
| | | | - Michael E. Scheurer
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77047, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77047, USA
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3
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Sahu S, Singh B, Kumar Rai A. Human endogenous retrovirus regulates the initiation and progression of cancers (Review). Mol Clin Oncol 2022; 17:143. [PMID: 36157315 PMCID: PMC9468830 DOI: 10.3892/mco.2022.2576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/22/2022] [Indexed: 11/05/2022] Open
Abstract
The expression of genes is altered in various diseases and is responsible for the disease's initiation, progression and pathology. Several other genes, predominantly inactivated, may become activated in a given condition and contribute to the initiation and progression of the disease. Similarly, human endogenous viruses (HERVs) are an incomplete, non-productive and inactive viral sequence present in the heterochromatin of the human genome, and are often referred to as junk DNA. HERVs were inserted into the host genome millions of years ago. However, they were silenced due to multiple mutations and recombination that occurred over time. However, their expression is increased in cancers due to either epigenetic or transcriptional dysregulation. Some of the HERVs having intact open reading frames have been reported to express virus-like particles, functional peptides and proteins involved in tumorigenesis. To summarize, there is involvement of different HERVs in the initiation and progression of several cancers. The present review aims to provide concise information on HERV and its involvement in the initiation and progression of multiple types of cancer.
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Affiliation(s)
- Srishti Sahu
- Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh 211004, India
| | - Bharat Singh
- Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh 211004, India
| | - Ambak Kumar Rai
- Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, Uttar Pradesh 211004, India
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4
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Lu X, Xu Q, Tong Y, Zhang Z, Dun G, Feng Y, Tang J, Han D, Mao Y, Deng L, He X, Li Q, Xiang Y, Wang F, Zeng D, Tang B, Mao X. Long non-coding RNA EVADR induced by Fusobacterium nucleatum infection promotes colorectal cancer metastasis. Cell Rep 2022; 40:111127. [PMID: 35858553 DOI: 10.1016/j.celrep.2022.111127] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/10/2022] [Accepted: 06/30/2022] [Indexed: 11/03/2022] Open
Abstract
Both Fusobacterium nucleatum (F. nucleatum) and long non-coding RNA (lncRNA) EVADR are associated with colorectal cancer (CRC), but their relationship with CRC metastasis and the mechanisms by which EVADR promotes CRC metastasis are poorly understood. Here, we report that F. nucleatum promotes colorectal cancer cell metastasis to the liver and lung and that it can be detected in CRC-metastasis colonization in mouse models. Furthermore, F. nucleatum upregulates the expression of EVADR, which can increase the metastatic ability of CRC cells in vivo and in vitro. Mechanistically, elevated EVADR serves as a modular scaffold for the Y-box binding protein 1 (YBX1) to directly enhance the translation of epithelial-mesenchymal transition (EMT)-related factors, such as Snail, Slug, and Zeb1. These findings suggest that EVADR induced by F. nucleatum promotes colorectal cancer metastasis through YBX1-dependent translation. The EVADR-YBX1 axis may be useful for the prevention and treatment of patients with F. nucleatum-associated CRC metastasis.
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Affiliation(s)
- Xiaoxue Lu
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Qiaolin Xu
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Yanan Tong
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Zhujun Zhang
- Department of Hospital Infection Control, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Guodong Dun
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Yuyang Feng
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Jie Tang
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Dan Han
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Yilan Mao
- Class of 2021 Undergraduate, Nursing College of Chongqing Medical University, Chongqing 400016, China
| | - Ling Deng
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Xiaoyi He
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Qian Li
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Yang Xiang
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - FengChao Wang
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Combined Injury, College of Preventive Medicine, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Dongzhu Zeng
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China.
| | - Bin Tang
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China.
| | - Xuhu Mao
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing 400038, China.
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5
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Ruberto S, Santovito A, Simula ER, Noli M, Manca MA, Sechi LA. Bisphenols induce human genomic damage and modulate HERVs/env expression. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2022; 63:275-285. [PMID: 36054626 PMCID: PMC9826028 DOI: 10.1002/em.22499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/01/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
Bisphenol A (BPA), a recognized endocrine-disrupting chemical, is used in the production of epoxy and polycarbonate resins. Since human exposure to BPA has been associated with increased cancer susceptibility, the market has shifted to products often labeled as "BPA free" containing BPA analogs such as bisphenol F (BPF) and bisphenol S (BPS). However, the European legislation on BPF and BPS is still unclear. This study analyzed the effects of BPA, BPF, and BPS exposure on human peripheral blood mononuclear cells by using in vitro micronucleus assay. Furthermore, it investigated the impact of bisphenols exposure on human endogenous retroviruses (HERVs) expression, which is implicated with the pathogenesis of several human diseases. The micronucleus assay revealed a significant genotoxic effect in peripheral blood cells after exposure to BPA and BPF at concentrations of 0.1, 0.05, and 0.025 μg/ml, and to BPS at 0.1 and 0.05 μg/ml. In addition, BPA exposure seems to upregulate the expression of HERVs, while a downregulation was observed after BPF and BPS treatments. Overall, our data showed the toxic effect of BPA and its analogs on circulating cells in the blood and demonstrated that they could modulate the HERVs expression.
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Affiliation(s)
- Stefano Ruberto
- Department of Biomedical SciencesDivision of Microbiology and Virology, University of SassariSassariItaly
| | - Alfredo Santovito
- Department of Life Sciences and Systems BiologyUniversity of TurinTorinoItaly
| | - Elena R. Simula
- Department of Biomedical SciencesDivision of Microbiology and Virology, University of SassariSassariItaly
| | - Marta Noli
- Department of Biomedical SciencesDivision of Microbiology and Virology, University of SassariSassariItaly
| | - Maria A. Manca
- Department of Biomedical SciencesDivision of Microbiology and Virology, University of SassariSassariItaly
| | - Leonardo A. Sechi
- Department of Biomedical SciencesDivision of Microbiology and Virology, University of SassariSassariItaly
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6
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Human Endogenous Retroviruses as Biomedicine Markers. Virol Sin 2021; 36:852-858. [PMID: 33905075 DOI: 10.1007/s12250-021-00387-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 03/15/2021] [Indexed: 11/27/2022] Open
Abstract
Human endogenous retroviruses (HERVs) were formed via ancient integration of exogenous retroviruses into the human genome and are considered to be viral "fossils". The human genome is embedded with a considerable amount of HERVs, witnessing the long-term evolutionary history of the viruses and the host. Most HERVs have lost coding capability during selection but still function in terms of HERV-mediated regulation of host gene expression. In this review, we summarize the roles of HERV activation in response to viral infections and diseases, and emphasize the potential use of HERVs as biomedicine markers in the early diagnosis of diseases such as cancer, which provides a new perspective for the clinical application of HERVs.
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7
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MacDonald KM, Benguerfi S, Harding SM. Alerting the immune system to DNA damage: micronuclei as mediators. Essays Biochem 2020; 64:753-764. [PMID: 32844183 PMCID: PMC7588664 DOI: 10.1042/ebc20200016] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/01/2020] [Accepted: 08/13/2020] [Indexed: 12/18/2022]
Abstract
Healthy cells experience thousands of DNA lesions per day during normal cellular metabolism, and ionizing radiation and chemotherapeutic drugs rely on DNA damage to kill cancer cells. In response to such lesions, the DNA damage response (DDR) activates cell-cycle checkpoints, initiates DNA repair mechanisms, or promotes the clearance of irreparable cells. Work over the past decade has revealed broader influences of the DDR, involving inflammatory gene expression following unresolved DNA damage, and immune surveillance of damaged or mutated cells. Subcellular structures called micronuclei, containing broken fragments of DNA or whole chromosomes that have been isolated away from the rest of the genome, are now recognized as one mediator of DDR-associated immune recognition. Micronuclei can initiate pro-inflammatory signaling cascades, or massively degrade to invoke distinct forms of genomic instability. In this mini-review, we aim to provide an overview of the current evidence linking the DDR to activation of the immune response through micronuclei formation, identifying key areas of interest, open questions, and emerging implications.
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Affiliation(s)
- Kate M MacDonald
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Soraya Benguerfi
- Princess Margaret Cancer Center, University Health Network, Toronto, ON, Canada
| | - Shane M Harding
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Princess Margaret Cancer Center, University Health Network, Toronto, ON, Canada
- Department of Radiation Oncology and Immunology, University of Toronto, Toronto, ON, Canada
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8
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Leruste A, Chauvin C, Pouponnot C, Bourdeaut F, Waterfall JJ, Piaggio E. Immune responses in genomically simple SWI/SNF-deficient cancers. Cancer 2020; 127:172-180. [PMID: 33079397 DOI: 10.1002/cncr.33172] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 06/27/2020] [Accepted: 07/23/2020] [Indexed: 01/09/2023]
Affiliation(s)
- Amaury Leruste
- Translational Research in Pediatric Oncology (RTOP) team, INSERM U830, Curie Institute Research Center, PSL Research University, Paris, France.,SIREDO Pediatric Cancer Center, Curie Institute, Paris, France.,Translational Research Department, Curie Institute Research Center, PSL Research University, Paris, France
| | - Céline Chauvin
- Translational Research in Pediatric Oncology (RTOP) team, INSERM U830, Curie Institute Research Center, PSL Research University, Paris, France.,SIREDO Pediatric Cancer Center, Curie Institute, Paris, France.,Translational Research Department, Curie Institute Research Center, PSL Research University, Paris, France
| | - Celio Pouponnot
- CNRS UMR 3347, INSERM U1021, Curie Institute Research Center, PSL Research University, Orsay, France
| | - Franck Bourdeaut
- Translational Research in Pediatric Oncology (RTOP) team, INSERM U830, Curie Institute Research Center, PSL Research University, Paris, France.,SIREDO Pediatric Cancer Center, Curie Institute, Paris, France.,Translational Research Department, Curie Institute Research Center, PSL Research University, Paris, France
| | - Joshua J Waterfall
- Translational Research Department, Curie Institute Research Center, PSL Research University, Paris, France.,Integrative Functional Genomics of Cancer (IFGC) team, INSERM U830, Curie Institute Research Center, PSL Research University, Paris, France
| | - Eliane Piaggio
- Translational Research Department, Curie Institute Research Center, PSL Research University, Paris, France.,Translational Immunotherapy (TransImm) team, INSERM U932, Curie Institute Research Center, PSL Research University, Paris, France
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9
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Ho AY, Wright JL, Blitzblau RC, Mutter RW, Duda DG, Norton L, Bardia A, Spring L, Isakoff SJ, Chen JH, Grassberger C, Bellon JR, Beriwal S, Khan AJ, Speers C, Dunn SA, Thompson A, Santa-Maria CA, Krop IE, Mittendorf E, King TA, Gupta GP. Optimizing Radiation Therapy to Boost Systemic Immune Responses in Breast Cancer: A Critical Review for Breast Radiation Oncologists. Int J Radiat Oncol Biol Phys 2020; 108:227-241. [PMID: 32417409 PMCID: PMC7646202 DOI: 10.1016/j.ijrobp.2020.05.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/24/2020] [Accepted: 05/07/2020] [Indexed: 12/13/2022]
Abstract
Immunotherapy using immune checkpoint blockade has revolutionized the treatment of many types of cancer. Radiation therapy (RT)-particularly when delivered at high doses using newer techniques-may be capable of generating systemic antitumor effects when combined with immunotherapy in breast cancer. These systemic effects might be due to the local immune-priming effects of RT resulting in the expansion and circulation of effector immune cells to distant sites. Although this concept merits further exploration, several challenges need to be overcome. One is an understanding of how the heterogeneity of breast cancers may relate to tumor immunogenicity. Another concerns the need to develop knowledge and expertise in delivery, sequencing, and timing of RT with immunotherapy. Clinical trials addressing these issues are under way. We here review and discuss the particular opportunities and issues regarding this topic, including the design of informative clinical and translational studies.
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Affiliation(s)
- Alice Y Ho
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
| | - Jean L Wright
- Department of Radiation Oncology, Johns Hopkins Cancer Center, Brooklandville, Maryland
| | - Rachel C Blitzblau
- Department of Radiation Oncology, Duke Cancer Center, Durham, North Carolina
| | - Robert W Mutter
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | - Dan G Duda
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Larry Norton
- Department of Medical Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Aditya Bardia
- Department of Medical Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Laura Spring
- Department of Medical Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Steven J Isakoff
- Department of Medical Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Jonathan H Chen
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Clemens Grassberger
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Jennifer R Bellon
- Department of Radiation Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Sushil Beriwal
- Department of Radiation Oncology, University of Pittsburgh Cancer Center, Pittsburgh, Pennslyvania
| | - Atif J Khan
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Corey Speers
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | - Samantha A Dunn
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - Alastair Thompson
- Department of Surgical Oncology, Baylor College of Medicine Medical Center, Houston, Texas
| | - Cesar A Santa-Maria
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ian E Krop
- Department of Medical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Elizabeth Mittendorf
- Department of Surgical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Tari A King
- Department of Surgical Oncology, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Gaorav P Gupta
- Department of Radiation Oncology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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10
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Lee AK, Pan D, Bao X, Hu M, Li F, Li CY. Endogenous Retrovirus Activation as a Key Mechanism of Anti-Tumor Immune Response in Radiotherapy. Radiat Res 2020; 193:305-317. [PMID: 32074012 DOI: 10.1667/rade-20-00013] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The generation of DNA double-strand breaks has historically been taught as the mechanism through which radiotherapy kills cancer cells. Recently, radiation-induced cytosolic DNA release and activation of the cGAS/STING pathway, with ensuing induction of interferon secretion and immune activation, have been recognized as important mechanisms for radiation-mediated anti-tumor efficacy. Here we demonstrate that radiation-induced activation of endogenous retroviruses (ERVs) also plays a major role in regulating the anti-tumor immune response during irradiation. Radiation-induced ERV-associated dsRNA transcription and subsequent activation of the innate antiviral MDA5/MAVS/TBK1 pathway led to downstream transcription of interferon-stimulated genes. Additionally, genetic knockout of KAP1, a chromatin modulator responsible for suppressing ERV transcription sites within the genome, enhanced the effect of radiation-induced anti-tumor response in vivo in two different tumor models. This anti-tumor response was immune-mediated and required an intact host immune system. Our findings indicate that radiation-induced ERV-dsRNA expression and subsequent immune response play critical roles in clinical radiotherapy, and manipulation of epigenetic regulators and the dsRNA-sensing innate immunity pathway could be promising targets to enhance the efficacy of radiotherapy and cancer immunotherapy.
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Affiliation(s)
- Andrew K Lee
- Department of Pharmacology and Cancer Biology, Duke University Graduate School, Durham, North Carolina
| | | | | | | | | | - Chuan-Yuan Li
- Department of Pharmacology and Cancer Biology, Duke University Graduate School, Durham, North Carolina.,Department of Dermatology.,Department of Duke Cancer Institute, Duke University School of Medicine, Durham, North Carolina
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11
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Zhang M, Liang JQ, Zheng S. Expressional activation and functional roles of human endogenous retroviruses in cancers. Rev Med Virol 2019; 29:e2025. [PMID: 30614117 PMCID: PMC6590502 DOI: 10.1002/rmv.2025] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 10/26/2018] [Accepted: 11/05/2018] [Indexed: 12/26/2022]
Abstract
Human endogenous retroviruses (HERVs) are widely believed to be remnants of ancestral germ line infections by exogenous retroviruses. Although HERVs are deemed as “nonfunctional DNAs” due to loss of most of their viral protein coding capacity during evolution as part of the human genome, cumulative evidences are showing the expressional activation and potential roles of HERVs in diseases especially cancers. Work by other researchers and us has observed the dysregulation of HERVs in cancers, identified new HERV‐related genes, and revealed their potential importance in cancer development. Here, we summarized the current knowledge on the mechanisms of the expressional activation and functional roles of HERVs, with a focus on the H family HERV (HERV‐H), in carcinogenesis. HERV expression is regulated by external chemical or physical substances and exogenous virus infection, as well as host factors such as epigenetic DNA methylation, transcription factors, cytokines, and small RNAs. Diverse roles of HERVs have been proposed by acting in the forms of noncoding RNAs, proteins, and transcriptional regulators during carcinogenesis. However, much remains to be learnt about the contributions of HERVs to human cancers. More investigation is warranted to elucidate the functions of these “fossil remnants” yet important viral DNAs in the human genome.
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Affiliation(s)
- Mengwen Zhang
- The Department of Plastic and Reconstructive Surgery, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.,Cancer Institute, Second Affiliated Hospital, and Ministry of Education Key Laboratory of Cancer Prevention and Intervention, Zhejiang University School of Medicine, Hangzhou, China
| | - Jessie 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, CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong, China
| | - Shu Zheng
- Cancer Institute, Second Affiliated Hospital, and Ministry of Education Key Laboratory of Cancer Prevention and Intervention, Zhejiang University School of Medicine, Hangzhou, China.,The Department of surgical oncology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
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12
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Lhuillier C, Vanpouille-Box C, Galluzzi L, Formenti SC, Demaria S. Emerging biomarkers for the combination of radiotherapy and immune checkpoint blockers. Semin Cancer Biol 2018; 52:125-134. [PMID: 29258856 PMCID: PMC6004231 DOI: 10.1016/j.semcancer.2017.12.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 12/11/2017] [Accepted: 12/13/2017] [Indexed: 12/19/2022]
Abstract
Over the past few years, multiple immune checkpoint blockers (ICBs) have achieved unprecedented clinical success and have been approved by regulatory agencies for the treatment of an increasing number of malignancies. However, only a limited fraction of patients responds to ICBs employed as a standalone intervention, calling for the development of combinatorial regimens. Radiation therapy (RT) stands out as a very promising candidate for this purpose. Indeed, RT mediates antineoplastic effects not only by cytotoxic and cytostatic mechanisms, but also by modulating immunological functions, both locally (within the irradiated field) and systemically. As combinatorial regimens involving RT and ICBs are being developed and clinically tested at an accelerating pace, it is paramount to identify biomarkers that reliably predict the likelihood of individual patients to respond. Here, we discuss emerging biomarkers that may potentially predict the response of cancer patients to RT plus ICBs.
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Affiliation(s)
- Claire Lhuillier
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA
| | | | - Lorenzo Galluzzi
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA; Sandra and Edward Meyer Cancer Center, New York, NY, USA
| | - Silvia Chiara Formenti
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA; Sandra and Edward Meyer Cancer Center, New York, NY, USA
| | - Sandra Demaria
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA; Sandra and Edward Meyer Cancer Center, New York, NY, USA; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA.
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13
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Morris G, Maes M, Murdjeva M, Puri BK. Do Human Endogenous Retroviruses Contribute to Multiple Sclerosis, and if So, How? Mol Neurobiol 2018; 56:2590-2605. [PMID: 30047100 PMCID: PMC6459794 DOI: 10.1007/s12035-018-1255-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 07/17/2018] [Indexed: 12/24/2022]
Abstract
The gammaretroviral human endogenous retrovirus (HERV) families MRSV/HERV-W and HERV-H (including the closely related HERV-Fc1) are associated with an increased risk of multiple sclerosis (MS). Complete HERV sequences betray their endogenous retroviral origin, with open reading frames in gag, pro, pol and env being flanked by two long terminal repeats containing promoter and enhancer sequences with the capacity to regulate HERV transactivation and the activity of host genes in spite of endogenous epigenetic repression mechanisms. HERV virions, RNA, cDNA, Gag and Env, and antibodies to HERV transcriptional products, have variously been found in the blood and/or brain and/or cerebrospinal fluid of MS patients, with the HERV expression level being associated with disease status. Furthermore, some HERV-associated single nucleotide polymorphisms (SNPs), such as rs662139 T/C in a 3-kb region of Xq22.3 containing a HERV-W env locus, and rs391745, upstream of the HERV-Fc1 locus on the X chromosome, are associated with MS susceptibility, while a negative association has been reported with SNPs in the tripartite motif-containing (TRIM) protein-encoding genes TRIM5 and TRIM22. Factors affecting HERV transcription include immune activation and inflammation, since HERV promoter regions possess binding sites for related transcription factors; oxidative stress, with oxidation of guanine to 8-oxoguanine and conversion of cytosine to 5-hydroxymethylcytosine preventing binding of methyl groups transferred by DNA methyltransferases; oxidative stress also inhibits the activity of deacetylases, thereby favouring the acetylation of histone lysine residues favouring gene expression; interferon beta; natalizumab treatment; impaired epigenetic regulation; and the sex of patients.
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Affiliation(s)
- Gerwyn Morris
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, Geelong, Victoria, Australia
| | - Michael Maes
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, Geelong, Victoria, Australia
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Marianna Murdjeva
- Department of Microbiology and Immunology, Medical University, Plovdiv, Bulgaria
| | - Basant K Puri
- Department of Medicine, Hammersmith Hospital, Imperial College London, London, UK.
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14
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Bustamante Rivera YY, Brütting C, Schmidt C, Volkmer I, Staege MS. Endogenous Retrovirus 3 - History, Physiology, and Pathology. Front Microbiol 2018; 8:2691. [PMID: 29379485 PMCID: PMC5775217 DOI: 10.3389/fmicb.2017.02691] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 12/26/2017] [Indexed: 01/05/2023] Open
Abstract
Endogenous viral elements (EVE) seem to be present in all eukaryotic genomes. The composition of EVE varies between different species. The endogenous retrovirus 3 (ERV3) is one of these elements that is present only in humans and other Catarrhini. Conservation of ERV3 in most of the investigated Catarrhini and the expression pattern in normal tissues suggest a putative physiological role of ERV3. On the other hand, ERV3 has been implicated in the pathogenesis of auto-immunity and cancer. In the present review we summarize knowledge about this interesting EVE. We propose the model that expression of ERV3 (and probably other EVE loci) under pathological conditions might be part of a metazoan SOS response.
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Affiliation(s)
| | - Christine Brütting
- Department of Paediatrics I, Martin Luther University Halle-Wittenberg, Halle, Germany.,Department of Neurology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Caroline Schmidt
- Department of Paediatrics I, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Ines Volkmer
- Department of Paediatrics I, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Martin S Staege
- Department of Paediatrics I, Martin Luther University Halle-Wittenberg, Halle, Germany
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15
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Jung YD, Lee HE, Jo A, Hiroo I, Cha HJ, Kim HS. Activity analysis of LTR12C as an effective regulatory element of the RAE1 gene. Gene 2017; 634:22-28. [PMID: 28867566 DOI: 10.1016/j.gene.2017.08.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 08/24/2017] [Indexed: 10/18/2022]
Abstract
Ribonucleic acid export 1 (RAE1) plays an important role in the export of mature mRNAs from the nucleus to the cytoplasm. Long terminal repeats (LTRs) became integrated into the human genome during primate evolution. One such repeat element, LTR12C, lies within a predicted regulatory region located upstream of the RAE1 gene. We examined the transcriptional activity of LTR12C by using the luciferase assay, and showed that the tandem repeat region (TRR) located within LTR12C was required for its regulatory function. A bioinformatics analysis revealed that the LTR12C element had multiple transcription factor binding sites specific for nuclear transcription factor Y (NF-Y), and the promoter activity of LTR12C was significantly decreased after NF-Y knockdown. Additionally, we discovered novel data indicating that LTR12C was initially inserted into the gorilla genome. Taken together, our results reveal that the TRR of LTR12C has powerful regulatory activity due to its NF-Y binding sites, and the integration of the LTR12C element into the primate genome during evolution may have affected RAE1 transcription.
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Affiliation(s)
- Yi-Deun Jung
- Biotherapeutics Translational Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon 34141, Republic of Korea
| | - Hee-Eun Lee
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea; Institute of Systems Biology, Pusan National University, Busan 46241, Republic of Korea
| | - Ara Jo
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea; Institute of Systems Biology, Pusan National University, Busan 46241, Republic of Korea
| | - Imai Hiroo
- Molecular Biology Section, Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Hee-Jae Cha
- Department of Parasitology and Genetics, College of Medicine, Kosin University, Busan, Republic of Korea
| | - Heui-Soo Kim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea; Institute of Systems Biology, Pusan National University, Busan 46241, Republic of Korea.
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16
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Pavlicev M, Hiratsuka K, Swaggart KA, Dunn C, Muglia L. Detecting endogenous retrovirus-driven tissue-specific gene transcription. Genome Biol Evol 2015; 7:1082-97. [PMID: 25767249 PMCID: PMC4419796 DOI: 10.1093/gbe/evv049] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Transposable elements (TEs) comprise approximately half of the human genome, and several independent lines of investigation have demonstrated their role in rewiring gene expression during development, evolution, and oncogenesis. The identification of their regulatory effects has largely been idiosyncratic, by linking activity with isolated genes. Their distribution throughout the genome raises critical questions—do these elements contribute to broad tissue- and lineage-specific regulation? If so, in what manner, as enhancers, promoters, RNAs? Here, we devise a novel approach to systematically dissect the genome-wide consequences of TE insertion on gene expression, and test the hypothesis that classes of endogenous retrovirus long terminal repeats (LTRs) exert tissue-specific regulation of adjacent genes. Using correlation of expression patterns across 18 tissue types, we reveal the tissue-specific uncoupling of gene expression due to 62 different LTR classes. These patterns are specific to the retroviral insertion, as the same genes in species without the LTRs do not exhibit the same effect. Although the LTRs can be transcribed themselves, the most highly transcribed TEs do not have the largest effects on adjacent regulation of coding genes, suggesting they function predominantly as enhancers. Moreover, the tissue-specific patterns of gene expression that are detected by our method arise from a limited number of genes, rather than as a general consequence of LTR integration. These findings identify basic principles of co-opting LTRs for genome evolution, and support the utility of our method for the analysis of TE, or other specific gene sets, in relation to the rest of the genome.
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Affiliation(s)
- Mihaela Pavlicev
- Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine
| | - Kaori Hiratsuka
- Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine
| | - Kayleigh A Swaggart
- Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine
| | - Caitlin Dunn
- Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine
| | - Louis Muglia
- Center for Prevention of Preterm Birth, Perinatal Institute, Cincinnati Children's Hospital Medical Center and Department of Pediatrics, University of Cincinnati College of Medicine
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17
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Emmer A, Staege MS, Kornhuber ME. The retrovirus/superantigen hypothesis of multiple sclerosis. Cell Mol Neurobiol 2014; 34:1087-96. [PMID: 25138639 DOI: 10.1007/s10571-014-0100-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 08/09/2014] [Indexed: 12/21/2022]
Abstract
The pathogenesis of multiple sclerosis (MS) is as yet unknown. Commonly, MS is assumed to be due to an autoimmune inflammation of the central nervous system (CNS). Neurodegeneration is regarded to be a secondary reaction. This concept is increasingly being challenged. Human endogenous retroviruses (HERV) that could be locally activated in the CNS have been proposed as an alternative concept. HERV-encoded envelope proteins (env) can act as strong immune stimulators (superantigens). Thus, slow disease progression following neurodegeneration might be induced by re-activation of HERV expression directly, while relapses in parallel to inflammation might be secondary to the expression of HERV-encoded superantigens. It has been shown previously that T-cell superantigens are capable to induce a cellular inflammatory reaction in the CNS of experimental animals similar to that in MS. Furthermore, B-cell superantigens have been shown to activate blood leucocytes in vitro to produce immunoglobulin in an oligoclonal manner. It remains to be established, whether the outlined hypothesis accords with all known features of MS. Furthermore, anti-HERV agents may be taken into consideration to enrich and improve MS therapy.
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Affiliation(s)
- Alexander Emmer
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany,
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18
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Rhyu DW, Kang YJ, Ock MS, Eo JW, Choi YH, Kim WJ, Leem SH, Yi JM, Kim HS, Cha HJ. Expression of human endogenous retrovirus env genes in the blood of breast cancer patients. Int J Mol Sci 2014; 15:9173-83. [PMID: 24964007 PMCID: PMC4100088 DOI: 10.3390/ijms15069173] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 05/13/2014] [Accepted: 05/13/2014] [Indexed: 11/16/2022] Open
Abstract
Human endogenous retroviruses (HERV) env proteins have been recently reported to be significantly up-regulated in certain cancers. Specifically, mRNA and protein levels of HERV-K (HML-2) are up-regulated in the blood plasma or serum of breast cancer patients. Here, we collected blood samples of 49 breast cancer patients and analyzed mRNA expressions of various HERVs env genes including HERV-R, HERV-H, HERV-K, and HERV-P by real-time PCR. The expression of env genes were significantly increased in the blood of primary breast cancer patients but were decreased in patients undergoing chemotherapy to a similar level with benign patients. When we compared the group currently undergoing chemotherapy and those patients undergoing chemotherapy simultaneously with radiotherapy, HERVs env genes were reduced more in the chemotherapy only group, suggesting that chemotherapy is more effective in reducing HERV env gene expression than is radiotherapy. Among chemotherapy groups, HERV env gene expression was the lowest in the taxotere- or taxol-treated group, suggesting that taxotere and taxol can reduce HERVs env expression. These data suggest the potential to use HERVs env genes as a diagnosis marker for primary breast cancer, and further studies are needed to identify the mechanism and physiological significance of the reduction of HERV env gene expression during chemotherapy.
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Affiliation(s)
- Dong-Won Rhyu
- Department of Surgery, Kosin University College of Medicine, Busan 602-072, Korea.
| | - Yun-Jeong Kang
- Department of Parasitology and Genetics, Kosin University College of Medicine, Busan 602-072, Korea.
| | - Mee-Sun Ock
- Department of Parasitology and Genetics, Kosin University College of Medicine, Busan 602-072, Korea.
| | - Jung-Woo Eo
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Korea.
| | - Yung-Hyun Choi
- Department of Biochemistry, College of Oriental Medicine, Dongeui University, Busan 614-052, Korea.
| | - Wun-Jae Kim
- Department of Urology, College of Medicine, Chungbuk National University, Cheongju 361-763, Korea.
| | - Sun-Hee Leem
- Department of Biological Science, Dong-A University, Busan 604-714, Korea.
| | - Joo-Mi Yi
- Dongnam Institute of Radiological & Medicine Sciences, Busan 619-953, Korea.
| | - Heui-Soo Kim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Korea.
| | - Hee-Jae Cha
- Department of Parasitology and Genetics, Kosin University College of Medicine, Busan 602-072, Korea.
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19
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Yu HL, Zhao ZK, Zhu F. The role of human endogenous retroviral long terminal repeat sequences in human cancer (Review). Int J Mol Med 2013; 32:755-62. [PMID: 23900638 DOI: 10.3892/ijmm.2013.1460] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 05/30/2013] [Indexed: 11/06/2022] Open
Abstract
Human endogenous retrovirus (HERV) and solitary long terminal repeats (LTRs) constitute 8% of the human genome. Although most HERV genes are partially deleted and not intact, HERV LTRs comprise features including promoters, enhancers, selective splicer sites and polyadenylation sites in order to regulate the expression of neighboring genes. Owing to the genetic instability of LTRs, their wide distributions along human chromosomes are not only non-random, but are also correlated with gene density. Considerable evidence indicates that HERV LTRs regulate the expression of their adjacent viral and cellular genes in placental development and tumorigenesis. However, the regulatory mechanism of HERV LTRs on the expression of its neighboring cancer-associated genes in human cancers remains to be elucidated. Insertional mutagenesis, recombination and polymorphism are three principal factors of LTR that contribute to its genetic instability. Moreover, genetic instability, hypomethylation, transactivation and the antisense transcript of LTRs enhance the activity of LTRs and regulate the expression of their adjacent genes in human cancers. Therefore, in the present review, we examined the mechanism of HERV LTRs in tumorigenesis in combination with the structure and function of LTRs.
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Affiliation(s)
- Hong-Lian Yu
- Department of Medical Microbiology, School of Medicine, Wuhan University, Wuhan, Hubei 430071, PR China
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