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Liang B, Yan T, Wei H, Zhang D, Li L, Liu Z, Li W, Zhang Y, Jiang N, Meng Q, Jiang G, Hu Y, Leng J. HERVK-mediated regulation of neighboring genes: implications for breast cancer prognosis. Retrovirology 2024; 21:4. [PMID: 38388382 PMCID: PMC10885364 DOI: 10.1186/s12977-024-00636-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 02/18/2024] [Indexed: 02/24/2024] Open
Abstract
Human endogenous retroviruses (HERVs) are the remnants of ancient retroviral infections integrated into the human genome. Although most HERVs are silenced or rendered inactive by various regulatory mechanisms, they retain the potential to influence the nearby genes. We analyzed the regulatory map of 91 HERV-Ks on neighboring genes in human breast cancer and investigated the impact of HERV-Ks on the tumor microenvironment (TME) and prognosis of breast cancer. Nine RNA-seq datasets were obtained from GEO and NCBI SRA. Differentially expressed genes and HERV-Ks were analyzed using DESeq2. Validation of high-risk prognostic candidate genes using TCGA data. These included Overall survival (multivariate Cox regression model), immune infiltration analysis (TIMER), tumor mutation burden (maftools), and drug sensitivity analysis (GSCA). A total of 88 candidate genes related to breast cancer prognosis were screened, of which CD48, SLAMF7, SLAMF1, IGLL1, IGHA1, and LRRC8A were key genes. Functionally, these six key genes were significantly enriched in some immune function-related pathways, which may be associated with poor prognosis for breast cancer (p = 0.00016), and the expression levels of these genes were significantly correlated with the sensitivity of breast cancer treatment-related drugs. Mechanistically, they may influence breast cancer development by modulating the infiltration of various immune cells into the TME. We further experimentally validated these genes to confirm the results obtained from bioinformatics analysis. This study represents the first report on the regulatory potential of HERV-K in the neighboring breast cancer genome. We identified three key HERV-Ks and five neighboring genes that hold promise as novel targets for future interventions and treatments for breast cancer.
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Affiliation(s)
- Boying Liang
- Department of Immunology, School of Basic Medical Sciences, Guangxi Medical University, Nanning, 530021, Guangxi, China
- Guangxi Key Laboratory of Translational Medicine for Treating High-Incidence Infectious Diseases with Integrative Medicine, Nanning, China
| | - Tengyue Yan
- Collaborative Innovation Centre of Regenerative Medicine and Medical Bioresource Development and Application Co-Constructed by the Province and Ministry, Guangxi Medical University, Nanning, China
| | - Huilin Wei
- School of Institute of Life Sciences, Guangxi Medical University, Nanning, China
| | - Die Zhang
- Collaborative Innovation Centre of Regenerative Medicine and Medical Bioresource Development and Application Co-Constructed by the Province and Ministry, Guangxi Medical University, Nanning, China
| | - Lanxiang Li
- Department of Immunology, School of Basic Medical Sciences, Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Zengjing Liu
- Genomic Experimental Center, Guangxi Medical University, Nanning, China
| | - Wen Li
- Genomic Experimental Center, Guangxi Medical University, Nanning, China
| | - Yuluan Zhang
- Genomic Experimental Center, Guangxi Medical University, Nanning, China
| | - Nili Jiang
- School of Institute of Life Sciences, Guangxi Medical University, Nanning, China
| | - Qiuxia Meng
- Genomic Experimental Center, Guangxi Medical University, Nanning, China
| | - Guiyang Jiang
- Genomic Experimental Center, Guangxi Medical University, Nanning, China
| | - Yanling Hu
- Department of Immunology, School of Basic Medical Sciences, Guangxi Medical University, Nanning, 530021, Guangxi, China.
- Collaborative Innovation Centre of Regenerative Medicine and Medical Bioresource Development and Application Co-Constructed by the Province and Ministry, Guangxi Medical University, Nanning, China.
- School of Institute of Life Sciences, Guangxi Medical University, Nanning, China.
- Genomic Experimental Center, Guangxi Medical University, Nanning, China.
| | - Jing Leng
- Department of Immunology, School of Basic Medical Sciences, Guangxi Medical University, Nanning, 530021, Guangxi, China.
- Guangxi Key Laboratory of Translational Medicine for Treating High-Incidence Infectious Diseases with Integrative Medicine, Nanning, China.
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DeMarino C, Nath A, Zhuang Z, Doucet-O’Hare TT. Does the interplay between human endogenous retrovirus K and extracellular vesicles contribute to aging? EXTRACELLULAR VESICLES AND CIRCULATING NUCLEIC ACIDS 2023; 4:548-56. [PMID: 38606283 PMCID: PMC11007738 DOI: 10.20517/evcna.2023.45] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
The role of extracellular vesicles (EVs), including retroviral-like particles (RVLPs), in pathogenic processes is currently a subject of active investigation. Several studies have identified mechanistic links between the increased presence of EVs and the process of senescence. A recent study reveals that the reverse transcribed complementary DNA (cDNA) of a human endogenous retroviral sequence can activate the innate immune system and result in tissue damage and/or the spread of cellular senescence to distant tissues. Several studies have linked EVs to age-related diseases, such as Alzheimer's disease and Parkinson's disease, and have included isolation of EVs from individuals with these diseases. Loss of epigenetic regulation, immune activation, and environmental stimuli can all lead to the expression of endogenous retroviruses and the incorporation of their proteins and transcripts into EVs. In addition, EVs disseminating these endogenous retroviral components have now been shown to act in a paracrine manner in multiple human diseases. Further investigation of the connection between EVs containing endogenous retroviral protein products or nucleotides should be pursued in models of age-related diseases.
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Affiliation(s)
- Catherine DeMarino
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Zhengping Zhuang
- Neuro-Oncology Branch, National Cancer Institute, Bethesda, MD 20892, USA
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Wei R, Zhang X, Li X, Wen J, Liu H, Fu J, Li L, Zhang W, Liu Z, Yang Y, Zou K. A rapid and stable spontaneous reprogramming system of Spermatogonial stem cells to Pluripotent State. Cell Biosci 2023; 13:222. [PMID: 38041111 PMCID: PMC10693117 DOI: 10.1186/s13578-023-01150-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 10/20/2023] [Indexed: 12/03/2023] Open
Abstract
BACKGROUND The scarcity of pluripotent stem cells poses a major challenge to the clinical application, given ethical and biosafety considerations. While germline stem cells commit to gamete differentiation throughout life, studies demonstrated the spontaneous acquisition of pluripotency by spermatogonial stem cells (SSCs) from neonatal testes at a low frequency (1 in 1.5 × 107). Notably, this process occurs without exogenous oncogenes or chemical supplementation. However, while knockout of the p53 gene accelerates the transformation of SSCs, it also increases risk and hampers their clinical use. RESULTS We report a transformation system that efficiently and stably convert SSCs into pluripotent stem cells around 10 passages with the morphology similar to that of epiblast stem cells, which convert to embryonic stem (ES) cell-like colonies after change with ES medium. Epidermal growth factor (EGF), leukemia inhibitory factor (LIF) and fresh mouse embryonic fibroblast feeder (MEF) are essential for transformation, and addition of 2i (CHIR99021 and PD0325901) further enhanced the pluripotency. Transcriptome analysis revealed that EGF activated the RAS signaling pathway and inhibited p38 to initiate transformation, and synergically cooperated with LIF to promote the transformation. CONCLUSION This system established an efficient and safe resource of pluripotent cells from autologous germline, and provide new avenues for regenerative medicine and animal cloning.
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Affiliation(s)
- Rui Wei
- Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
- Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaoyu Zhang
- Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
- Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaoxiao Li
- Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
- Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jian Wen
- Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
- Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hongyang Liu
- Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
- Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jiqiang Fu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science & Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai, 200031, China
| | - Li Li
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science & Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai, 200031, China
| | - Wenyi Zhang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, 211166, China
| | - Zhen Liu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science & Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai, 200031, China
| | - Yang Yang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing, 211166, China.
| | - Kang Zou
- Germline Stem Cells and Microenvironment Lab, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
- Stem Cell Research and Translation Center, Nanjing Agricultural University, Nanjing, 210095, China.
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4
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Shah AH, Rivas SR, Doucet-O'Hare TT, Govindarajan V, DeMarino C, Wang T, Ampie L, Zhang Y, Banasavadi-Siddegowda YK, Walbridge S, Maric D, Garcia-Montojo M, Suter RK, Lee MH, Zaghloul KA, Steiner J, Elkahloun AG, Chandar J, Seetharam D, Desgraves J, Li W, Johnson K, Ivan ME, Komotar RJ, Gilbert MR, Heiss JD, Nath A. Human endogenous retrovirus K contributes to a stem cell niche in glioblastoma. J Clin Invest 2023; 133:e167929. [PMID: 37395282 DOI: 10.1172/jci167929] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 05/19/2023] [Indexed: 07/04/2023] Open
Abstract
Human endogenous retroviruses (HERVs) are ancestral viral relics that constitute nearly 8% of the human genome. Although normally silenced, the most recently integrated provirus HERV-K (HML-2) can be reactivated in certain cancers. Here, we report pathological expression of HML-2 in malignant gliomas in both cerebrospinal fluid and tumor tissue that was associated with a cancer stem cell phenotype and poor outcomes. Using single-cell RNA-Seq, we identified glioblastoma cellular populations with elevated HML-2 transcripts in neural progenitor-like cells (NPC-like) that drive cellular plasticity. Using CRISPR interference, we demonstrate that HML-2 critically maintained glioblastoma stemness and tumorigenesis in both glioblastoma neurospheres and intracranial orthotopic murine models. Additionally, we demonstrate that HML-2 critically regulated embryonic stem cell programs in NPC-derived astroglia and altered their 3D cellular morphology by activating the nuclear transcription factor OCT4, which binds to an HML-2-specific long-terminal repeat (LTR5Hs). Moreover, we discovered that some glioblastoma cells formed immature retroviral virions, and inhibiting HML-2 expression with antiretroviral drugs reduced reverse transcriptase activity in the extracellular compartment, tumor viability, and pluripotency. Our results suggest that HML-2 fundamentally contributes to the glioblastoma stem cell niche. Because persistence of glioblastoma stem cells is considered responsible for treatment resistance and recurrence, HML-2 may serve as a unique therapeutic target.
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Affiliation(s)
- Ashish H Shah
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Sarah R Rivas
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Tara T Doucet-O'Hare
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Vaidya Govindarajan
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Catherine DeMarino
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Tongguang Wang
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Leonel Ampie
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Yong Zhang
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | | | - Stuart Walbridge
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Dragan Maric
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Marta Garcia-Montojo
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Robert K Suter
- Georgetown University, Bioinformatics Section, Washington, DC, USA
| | - Myoung-Hwa Lee
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Kareem A Zaghloul
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Joseph Steiner
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Abdel G Elkahloun
- Cancer Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, Maryland, USA
| | - Jay Chandar
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Deepa Seetharam
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Jelisah Desgraves
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Wenxue Li
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Kory Johnson
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Michael E Ivan
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Ricardo J Komotar
- University of Miami School of Medicine, Department of Neurosurgery, Miami, Florida, USA
| | - Mark R Gilbert
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - John D Heiss
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Avindra Nath
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
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5
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Dang DD, Rosenblum JS, Shah AH, Zhuang Z, Doucet-O’Hare TT. Epigenetic Regulation in Primary CNS Tumors: An Opportunity to Bridge Old and New WHO Classifications. Cancers (Basel) 2023; 15:2511. [PMID: 37173979 PMCID: PMC10177493 DOI: 10.3390/cancers15092511] [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: 02/17/2023] [Revised: 04/22/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
Originally approved in 1979, a specific grading classification for central nervous system (CNS) tumors was devised by the World Health Organization (WHO) in an effort to guide cancer treatment and better understand prognosis. These "blue books" have since undergone several iterations based on tumor location, advancements in histopathology, and most recently, diagnostic molecular pathology in its fifth edition. As new research methods have evolved to elucidate complex molecular mechanisms of tumorigenesis, a need to update and integrate these findings into the WHO grading scheme has become apparent. Epigenetic tools represent an area of burgeoning interest that encompasses all non-Mendelian inherited genetic features affecting gene expression, including but not limited to chromatin remodeling complexes, DNA methylation, and histone regulating enzymes. The SWItch/Sucrose non-fermenting (SWI/SNF) chromatin remodeling complex is the largest mammalian family of chromatin remodeling proteins and is estimated to be altered in 20-25% of all human malignancies; however, the ways in which it contributes to tumorigenesis are not fully understood. We recently discovered that CNS tumors with SWI/SNF mutations have revealed an oncogenic role for endogenous retroviruses (ERVs), remnants of exogenous retroviruses that integrated into the germline and are inherited like Mendelian genes, several of which retain open reading frames for proteins whose expression putatively contributes to tumor formation. Herein, we analyzed the latest WHO classification scheme for all CNS tumors with documented SWI/SNF mutations and/or aberrant ERV expression, and we summarize this information to highlight potential research opportunities that could be integrated into the grading scheme to better delineate diagnostic criteria and therapeutic targets.
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Affiliation(s)
- Danielle D. Dang
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jared S. Rosenblum
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ashish H. Shah
- Section of Virology and Immunotherapy, Department of Neurosurgery, Leonard M. Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Zhengping Zhuang
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tara T. Doucet-O’Hare
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Hosseiniporgham S, Sechi LA. Anti-HERV-K Drugs and Vaccines, Possible Therapies against Tumors. Vaccines (Basel) 2023; 11:vaccines11040751. [PMID: 37112663 PMCID: PMC10144246 DOI: 10.3390/vaccines11040751] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 03/31/2023] Open
Abstract
The footprint of human endogenous retroviruses (HERV), specifically HERV-K, has been found in malignancies, such as melanoma, teratocarcinoma, osteosarcoma, breast cancer, lymphoma, and ovary and prostate cancers. HERV-K is characterized as the most biologically active HERV due to possession of open reading frames (ORF) for all Gag, Pol, and Env genes, which enables it to be more infective and obstructive towards specific cell lines and other exogenous viruses, respectively. Some factors might contribute to carcinogenicity and at least one of them has been recognized in various tumors, including overexpression/methylation of long interspersed nuclear element 1 (LINE-1), HERV-K Gag, and Env genes themselves plus their transcripts and protein products, and HERV-K reverse transcriptase (RT). Therapies effective for HERV-K-associated tumors mostly target invasive autoimmune responses or growth of tumors through suppression of HERV-K Gag or Env protein and RT. To design new therapeutic options, more studies are needed to better understand whether HERV-K and its products (Gag/Env transcripts and HERV-K proteins/RT) are the initiators of tumor formation or just the disorder’s developers. Accordingly, this review aims to present evidence that highlights the association between HERV-K and tumorigenicity and introduces some of the available or potential therapies against HERV-K-induced tumors.
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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: 9] [Impact Index Per Article: 9.0] [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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8
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Rivas SR, Valdez MJM, Govindarajan V, Seetharam D, Doucet-O’Hare TT, Heiss JD, Shah AH. The Role of HERV-K in Cancer Stemness. Viruses 2022; 14:v14092019. [PMID: 36146825 PMCID: PMC9504571 DOI: 10.3390/v14092019] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/29/2022] [Accepted: 09/05/2022] [Indexed: 12/15/2022] Open
Abstract
Human endogenous retrovirus-K (HERV-K) is the most recently integrated retrovirus in the human genome, with implications for multiple disorders, including cancer. Although typically transcriptionally silenced in normal adult cells, dysregulation of HERV-K (HML-2) elements has been observed in cancer, including breast, germ cell tumors, pancreatic, melanoma, and brain cancer. While multiple methods of carcinogenesis have been proposed, here we discuss the role of HERV-K (HML-2) in the promotion and maintenance of the stem-cell in cancer. Aberrant expression of HERV-K has been shown to promote expression of stem cell markers and promote dedifferentiation. In this review, we discuss HERV-K (HML-2) as a potential therapeutic target based on evidence that some tumors depend on the expression of its proteins for survival.
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Affiliation(s)
- Sarah R. Rivas
- Surgical Neurology Branch, National Institute of Neurological Diseases and Stroke, Bethesda, MD 20892, USA
- Correspondence: (S.R.R.); (A.H.S.)
| | - Mynor J. Mendez Valdez
- Section of Virology and Immunotherapy, Department of Neurosurgery, Leonard M. Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Vaidya Govindarajan
- Section of Virology and Immunotherapy, Department of Neurosurgery, Leonard M. Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Deepa Seetharam
- Section of Virology and Immunotherapy, Department of Neurosurgery, Leonard M. Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Tara T. Doucet-O’Hare
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - John D. Heiss
- Surgical Neurology Branch, National Institute of Neurological Diseases and Stroke, Bethesda, MD 20892, USA
| | - Ashish H. Shah
- Section of Virology and Immunotherapy, Department of Neurosurgery, Leonard M. Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Correspondence: (S.R.R.); (A.H.S.)
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Li W, Pandya D, Pasternack N, Garcia-Montojo M, Henderson L, Kozak CA, Nath A. Retroviral Elements in Pathophysiology and as Therapeutic Targets for Amyotrophic Lateral Sclerosis. Neurotherapeutics 2022; 19:1085-1101. [PMID: 35415778 PMCID: PMC9587200 DOI: 10.1007/s13311-022-01233-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2022] [Indexed: 10/18/2022] Open
Abstract
The study of the role of retroviruses in amyotrophic lateral sclerosis (ALS) dates back to the 1960s shortly after transposable elements themselves were first discovered. It was quickly realized that in wild mice both horizontal and vertical transmissions of retroviral elements were key to the development of an ALS-like syndrome leading to the postulate that endogenous retroviruses (ERVs) contribute significantly to the pathogenicity of this disease. Subsequent studies identified retroviral reverse transcriptase activity in brains of individuals with ALS from Guam. However, except for a single study from the former Soviet Union, ALS could not be transmitted to rhesus macaques. The discovery of an ALS-like syndrome in human immunodeficiency virus (HIV) and human T cell leukemia virus infected individuals led to renewed interest in the field and reverse transcriptase activity was found in the blood and cerebrospinal fluid of individuals with sporadic ALS. However, exogenous retroviruses could not be found in individuals with ALS which further reinforced the possibility of involvement of a human ERV (HERV). The first demonstration of the involvement of a HERV was the discovery of the activation of human endogenous retrovirus-K subtype HML-2 in the brains of individuals with ALS. The envelope protein of HML-2 is neurotoxic and transgenic animals expressing the envelope protein develop an ALS-like syndrome. Activation of HML-2 occurs in the context of generalized transposable element activation and is not specific for ALS. Individuals with HIV-associated ALS show a remarkable response to antiretroviral therapy; however, antiretroviral trials in ALS down-regulate HML-2 without ameliorating the disease. This highlights the need for specific drugs to be developed against HML-2 as a novel therapeutic target for ALS. Other approaches might include antisense oligonucleotides, shRNA targeted against the envelope gene or antibodies that can target the extracellular envelope protein. Future clinical trials in ALS should consider combination therapies to control these ERVs.
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Affiliation(s)
- Wenxue Li
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Darshan Pandya
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Nicholas Pasternack
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Marta Garcia-Montojo
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Lisa Henderson
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Christine A Kozak
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA.
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10
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Zhang C, Li H. Molecular targeted therapies for pediatric atypical teratoid/rhabdoid tumors. Pediatr Investig 2022; 6:111-122. [PMID: 35774526 PMCID: PMC9218972 DOI: 10.1002/ped4.12325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 04/26/2022] [Indexed: 01/01/2023] Open
Affiliation(s)
- Chang Zhang
- Department of Neurosurgery Children's Hospital of Fudan University Shanghai China
| | - Hao Li
- Department of Neurosurgery Children's Hospital of Fudan University Shanghai China
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Shah AH, Govindarajan V, Doucet-O'Hare TT, Rivas S, Ampie L, DeMarino C, Banasavadi-Siddegowda YK, Zhang Y, Johnson KR, Almsned F, Gilbert MR, Heiss JD, Nath A. Differential expression of an endogenous retroviral element [HERV-K(HML-6)] is associated with reduced survival in glioblastoma patients. Sci Rep 2022; 12:6902. [PMID: 35477752 PMCID: PMC9046263 DOI: 10.1038/s41598-022-10914-5] [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: 12/26/2021] [Accepted: 04/04/2022] [Indexed: 11/09/2022] Open
Abstract
Comprising approximately 8% of our genome, Human Endogenous RetroViruses (HERVs) represent a class of germline retroviral infections that are regulated through epigenetic modifications. In cancer cells, which often have epigenetic dysregulation, HERVs have been implicated as potential oncogenic drivers. However, their role in gliomas is not known. Given the link between HERV expression in cancer cell lines and the distinct epigenetic dysregulation in gliomas, we utilized a tailored bioinformatic pipeline to characterize and validate the glioma retrotranscriptome and correlate HERV expression with locus-specific epigenetic modifications. We identified robust overexpression of multiple HERVs in our cell lines, including a retroviral transcript, HML-6, at 19q13.43b in glioblastoma cells. HERV expression inversely correlated with loci-specific DNA methylation. HML-6 contains an intact open reading frame encoding a small envelope protein, ERVK3-1. Increased expression of ERVK3-1 in GBM patients is associated with a poor prognosis independent of IDH-mutational status. Our results suggest that not only is HML-6 uniquely overexpressed in highly invasive cell lines and tissue samples, but also its gene product, ERVK3-1, may be associated with reduced survival in GBM patients. These results may have implications for both the tumor biology of GBM and the role of ERVK3-1 as a potential therapeutic target.
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Affiliation(s)
- Ashish H Shah
- Surgical Neurology Branch, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA.
| | - Vaidya Govindarajan
- Department of Neurosurgery, University of Miami School of Medicine, Miami, FL, USA
| | - Tara T Doucet-O'Hare
- Center for Cancer Research (CCR), National Institutes of Health, National Cancer Institute (NCI), Neuro-Oncology Branch (NOB), Bethesda, MD, USA
| | - Sarah Rivas
- Surgical Neurology Branch, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Leo Ampie
- Surgical Neurology Branch, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Catherine DeMarino
- Surgical Neurology Branch, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | | | - Yong Zhang
- Bioinformatics Section, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Kory R Johnson
- Bioinformatics Section, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Fahad Almsned
- Bioinformatics Section, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Mark R Gilbert
- Center for Cancer Research (CCR), National Institutes of Health, National Cancer Institute (NCI), Neuro-Oncology Branch (NOB), Bethesda, MD, USA
| | - John D Heiss
- Surgical Neurology Branch, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Avindra Nath
- Surgical Neurology Branch, National Institutes of Health, National Institute of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
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12
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Müller MD, Holst PJ, Nielsen KN. A Systematic Review of Expression and Immunogenicity of Human Endogenous Retroviral Proteins in Cancer and Discussion of Therapeutic Approaches. Int J Mol Sci 2022; 23:ijms23031330. [PMID: 35163254 PMCID: PMC8836156 DOI: 10.3390/ijms23031330] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 02/06/2023] Open
Abstract
Human endogenous retroviruses (HERVs) are remnants of ancient retroviral infections that have become fixed in the human genome. While HERV genes are typically silenced in healthy somatic cells, there are numerous reports of HERV transcription and translation across a wide spectrum of cancers, while T and B cell responses against HERV proteins have been detected in cancer patients. This review systematically categorizes the published evidence on the expression of and adaptive immune response against specific HERVs in distinct cancer types. A systematic literature search was performed using Medical Search Headings (MeSH) in the PubMed/Medline database. Papers were included if they described the translational activity of HERVs. We present multiple tables that pair the protein expression of specific HERVs and cancer types with information on the quality of the evidence. We find that HERV-K is the most investigated HERV. HERV-W (syncytin-1) is the second-most investigated, while other HERVs have received less attention. From a therapeutic perspective, HERV-K and HERV-E are the only HERVs with experimental demonstration of effective targeted therapies, but unspecific approaches using antiviral and demethylating agents in combination with chemo- and immunotherapies have also been investigated.
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Affiliation(s)
- Mikkel Dons Müller
- Institute of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen N, Denmark;
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Durnaoglu S, Lee SK, Ahnn J. Human Endogenous Retroviruses as Gene Expression Regulators: Insights from Animal Models into Human Diseases. Mol Cells 2021; 44:861-878. [PMID: 34963103 PMCID: PMC8718366 DOI: 10.14348/molcells.2021.5016] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 11/27/2022] Open
Abstract
The human genome contains many retroviral elements called human endogenous retroviruses (HERVs), resulting from the integration of retroviruses throughout evolution. HERVs once were considered inactive junk because they are not replication-competent, primarily localized in the heterochromatin, and silenced by methylation. But HERVs are now clearly shown to actively regulate gene expression in various physiological and pathological conditions such as developmental processes, immune regulation, cancers, autoimmune diseases, and neurological disorders. Recent studies report that HERVs are activated in patients suffering from coronavirus disease 2019 (COVID-19), the current pandemic caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. In this review, we describe internal and external factors that influence HERV activities. We also present evidence showing the gene regulatory activity of HERV LTRs (long terminal repeats) in model organisms such as mice, rats, zebrafish, and invertebrate models of worms and flies. Finally, we discuss several molecular and cellular pathways involving various transcription factors and receptors, through which HERVs affect downstream cellular and physiological events such as epigenetic modifications, calcium influx, protein phosphorylation, and cytokine release. Understanding how HERVs participate in various physiological and pathological processes will help develop a strategy to generate effective therapeutic approaches targeting HERVs.
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Affiliation(s)
- Serpen Durnaoglu
- Department of Life Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
| | - Sun-Kyung Lee
- Department of Life Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
| | - Joohong Ahnn
- Department of Life Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
- Research Institute for Natural Sciences, College of Natural Sciences, Hanyang University, Seoul 04763, Korea
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14
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Endogenous Retroviral Elements in Human Development and Central Nervous System Embryonal Tumors. J Pers Med 2021; 11:jpm11121332. [PMID: 34945804 PMCID: PMC8708524 DOI: 10.3390/jpm11121332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 01/21/2023] Open
Abstract
Human endogenous retroviruses (HERVs), which are critical to normal embryologic development and downregulated during normal maturation, have been implicated in a variety of cancers. Abnormal persistent production of HERVs has been suggested to play a role in oncogenesis and to confer stem cell properties to cells. We recently demonstrated that the most recently incorporated HERV element (HERV-K HML-2) has been associated with the pathogenesis of the embryonal atypical teratoid rhabdoid tumor (AT/RT), shifting our understanding of embryonal tumor development. HML-2 expression is vital for proper human development and its expression is suppressed via methylation or chromatin remodeling as cells differentiate. We previously found that dysfunctional chromatin remodeling due to loss of SMARCB1 expression induces HML-2 envelope (env) expression, impairing cellular differentiation and migration, and facilitating tumor growth in AT/RT. Epigenetic dysregulation in other embryonal tumors with concomitant expression of stem-cell markers may facilitate HML-2 expression. Future studies could utilize HML-2 as potential diagnostic criteria, use its expression as a treatment biomarker, and investigate the efficacy of therapies targeting cells with high HML-2 expression.
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