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Soleimani MF, Ayubi E, Khosronezhad S, Hasler G, Amiri MR, Beikpour F, Jalilian FA. Human endogenous retroviruses type W (HERV-) activation and schizophrenia: A meta-analysis. Schizophr Res 2024; 271:220-227. [PMID: 39053037 DOI: 10.1016/j.schres.2024.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 07/06/2024] [Accepted: 07/07/2024] [Indexed: 07/27/2024]
Abstract
OBJECTIVE Human endogenous retroviruses (HERV) are the remnants of infections that occurred million years ago. They gradually integrated into the human genome, comprising 8 % of it. There are growing reports suggesting their potential role in various diseases, including schizophrenia. Schizophrenia, a serious psychiatric disorder, is caused by the interaction of genetic and environmental factors. In the present paper, we investigated studies focusing on the association between schizophrenia and HERV-W. METHODS We registered this study at PROSPERO (registration number: CRD42022301122). The entire steps of this study were based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. We searched PubMed, Scopus, Web of Science, and Google Scholar up to 1 August 2022. Heterogeneity was estimated through I2 statistics, and the association was measured using the first estimate and penalization methods. RESULTS Finally, 13 eligible studies were analyzed, including 698 cases and 728 controls. The overall odds ratio indicated a significant association in both the first estimate (OR = 9.34, 95 % CI = 4.92-17.75; P = 0.002) and penalization (OR = 7.38, 95 % CI = 4.15-13.10; P = 0.003) methods. In the subgroup analysis, among HERV-W fragments, the HERV-W envelope protein or RNA (OR = 11.41, 95 % CI: 5.67-22.97; P = 0.03) showed the strongest association with schizophrenia. CONCLUSION Our meta-analysis showed that HERV-W is significantly associated with schizophrenia. More studies are required to determine the pathophysiological mechanism and the diagnostic, prognostic, and therapeutic value of HERV-W in schizophrenia.
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Affiliation(s)
| | - Erfan Ayubi
- Social Determinants of Health Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Saman Khosronezhad
- Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Gregor Hasler
- University of Fribourg, Center for Psychiatric Research, Switzerland
| | - Mohammad Reza Amiri
- Department of Medical Library and Information Sciences, School of Paramedicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Farzad Beikpour
- Department of Pediatrics, School of Medicine, Washington University, St. Louis, MO, 63110, USA
| | - Farid Azizi Jalilian
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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Rangel SC, da Silva MD, Natrielli Filho DG, Santos SN, do Amaral JB, Victor JR, Silva KCN, Tuleta ID, França CN, Shio MT, Neves LM, Bachi ALL, da Silva Nali LH. HERV-W upregulation expression in bipolar disorder and schizophrenia: unraveling potential links to systemic immune/inflammation status. Retrovirology 2024; 21:7. [PMID: 38644495 PMCID: PMC11034070 DOI: 10.1186/s12977-024-00640-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 04/01/2024] [Indexed: 04/23/2024] Open
Abstract
BACKGROUND Bipolar disorder (BD) and schizophrenia (SZ) are the two main mental disorders with unknown etiology that significantly impact individuals' quality of life. The potential pro-inflammatory role in their pathogenesis is postulated and Human Endogenous Retrovirus W (HERV-W) is an emerging candidate to modulate this pathogenic finding. HERVs, ancient retroviruses in the human genome, may play roles in inflammation and disease pathogenesis. Despite HERVs' involvement in autoimmune diseases, their influence on mental disorders remains underexplored. Therefore, the aim of this study was to assess the level of HERV-W-env expression and the systemic inflammatory profile through the concentration of IL-2, IL-4, IL-6, IL-10, TNF-α and INF-γ cytokines in BD and SZ patients. RESULTS All participants showed HERV-W-env expression, but its expression was higher in mental disorder patients (p < 0.01) than in control. When separated, SZ individuals exhibited higher HERV-W expression than the control group (p < 0.01). Higher serum levels of TNF-α and IL-10 were found in BD (p = 0.0001 and p = 0.001, respectively) and SZ (p = 0.01) and p = 0.01, respectively) than in the control group, while SZ showed decreased levels IFN-γ and IL-2 as compared to controls (p = 0.05) and BD patients (p = 0.05), respectively. Higher TNF-α/IL-4 and TNF-α/IL-10 ratios, and lower IFN-γ/IL-10 were observed in BD and SZ patients than controls. Significant negative correlation between HERV-W-env expression and IL-10 (r=-0.47 p < 0.05), as well as positive correlations between HERV-W-env expression and TNF-α/IL-10 or IFN-γ/IL-10 ratios (r = 0.48 p < 0.05 and r = 0.46 p < 0.05, respectively) were found in BD patients. CONCLUSION These findings suggest not only a potential link between HERV-W-env expression both in BD and SZ, but also a possible involvement of systemic inflammatory status in BD patients.
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Affiliation(s)
- Sara Coelho Rangel
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - Michelly Damasceno da Silva
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - Décio Gilberto Natrielli Filho
- Hospital Escola Wladimir Arruda- Departamento de Psiquiatria- Santo Amaro University, Rua Prof. Enéas de Siqueira Neto, 340, São Paulo, Brazil
| | - Samuel Nascimento Santos
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - Jonatas Bussador do Amaral
- Ent Research Lab, Department of Otorhinolaryngology-Head and Neck Surgery, Federal University of Sao Paulo, São Paulo, Brazil
| | - Jefferson Russo Victor
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | | | - Izabela Dorota Tuleta
- Department of Medicine-Cardiology, Albert Einstein College of Medicine, New York, EUA, USA
| | - Carolina Nunes França
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - Marina Tiemi Shio
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - Lucas Melo Neves
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - André Luis Lacerda Bachi
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil
| | - Luiz Henrique da Silva Nali
- Post-graduation Program in Health Sciences, Santo Amaro University, Rua Isabel Schmitt, 540, São Paulo, Brazil.
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Han S, Li Y, Gao J. Peripheral blood MicroRNAs as biomarkers of schizophrenia: expectations from a meta-analysis that combines deep learning methods. World J Biol Psychiatry 2024; 25:65-81. [PMID: 37703215 DOI: 10.1080/15622975.2023.2258975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/13/2023] [Accepted: 09/11/2023] [Indexed: 09/15/2023]
Abstract
OBJECTIVES This study aimed at identifying reliable differentially expressed miRNAs (DEMs) for schizophrenia in blood via meta-analyses combined with deep learning methods. METHODS First, we meta-analysed published DEMs. Then, we enriched the pool of schizophrenia-associated miRNAs by applying two computational learning methods to identify candidate biomarkers and verified the results in external datasets. RESULTS In total, 27 DEMs were found to be statistically significant (p < .05). Ten candidate schizophrenia-associated miRNAs were identified through computational learning methods. The diagnostic efficiency was verified on a blood-miRNA dataset (GSE54578) with a random forest (RF) model and achieved an area under the curve (AUC) of 0.83 ± 0.14. Moreover, 855 experimentally validated target genes for these candidate miRNAs were retrieved, and 11 hub genes were identified. Enrichment analysis revealed that the main functions in which the target genes were enriched were those related to cell signalling, prenatal infections, cancers, cell deaths, oxidative stress, endocrine disorders, transcription regulation, and kinase activities. The diagnostic ability of the hub genes was reflected in a comparably good average AUC of 0.77 ± 0.09 for an external dataset (GSE38484). CONCLUSIONS A meta-analysis that combines computational and mathematical methods provides a reliable tool for identifying candidate biomarkers of schizophrenia.
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Affiliation(s)
- Shiyuan Han
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yongning Li
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- Department of International Medical Service, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jun Gao
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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Katoh H, Honda T. Roles of Human Endogenous Retroviruses and Endogenous Virus-Like Elements in Cancer Development and Innate Immunity. Biomolecules 2023; 13:1706. [PMID: 38136578 PMCID: PMC10741599 DOI: 10.3390/biom13121706] [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: 10/28/2023] [Revised: 11/18/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Human endogenous retroviruses (HERVs) are remnants of ancient retroviral infections in the host genome. Although mutations and silencing mechanisms impair their original role in viral replication, HERVs are believed to play roles in various biological processes. Long interspersed nuclear elements (LINEs) are non-LTR retrotransposons that have a lifecycle resembling that of retroviruses. Although LINE expression is typically silenced in somatic cells, it also contributes to various biological processes. The aberrant expression of HERVs and LINEs is closely associated with the development of cancer and/or immunological diseases, suggesting that they are integrated into various pathways related to the diseases. HERVs/LINEs control gene expression depending on the context as promoter/enhancer elements. Some RNAs and proteins derived from HERVs/LINEs have oncogenic potential, whereas others stimulate innate immunity. Non-retroviral endogenous viral elements (nrEVEs) are a novel type of virus-like element in the genome. nrEVEs may also be involved in host immunity. This article provides a current understanding of how these elements impact cellular physiology in cancer development and innate immunity, and provides perspectives for future studies.
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Affiliation(s)
- Hirokazu Katoh
- Department of Virology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8558, Japan;
| | - Tomoyuki Honda
- Department of Virology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8558, Japan;
- Department of Virology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
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Wu X, Liu L, Xue X, Li X, Zhao K, Zhang J, Li W, Yao W, Ding S, Jia C, Zhu F. Captive ERVWE1 triggers impairment of 5-HT neuronal plasticity in the first-episode schizophrenia by post-transcriptional activation of HTR1B in ALKBH5-m6A dependent epigenetic mechanisms. Cell Biosci 2023; 13:213. [PMID: 37990254 PMCID: PMC10664518 DOI: 10.1186/s13578-023-01167-4] [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: 07/27/2023] [Accepted: 11/07/2023] [Indexed: 11/23/2023] Open
Abstract
BACKGROUND Abnormalities in the 5-HT system and synaptic plasticity are hallmark features of schizophrenia. Previous studies suggest that the human endogenous retrovirus W family envelope (ERVWE1) is an influential risk factor for schizophrenia and inversely correlates with 5-HT4 receptor in schizophrenia. To our knowledge, no data describes the effect of ERVWE1 on 5-HT neuronal plasticity. N6-methyladenosine (m6A) regulates gene expression and impacts synaptic plasticity. Our research aims to systematically investigate the effects of ERVWE1 on 5-HT neuronal plasticity through m6A modification in schizophrenia. RESULTS HTR1B, ALKBH5, and Arc exhibited higher levels in individuals with first-episode schizophrenia compared to the controls and showed a strong positive correlation with ERVWE1. Interestingly, HTR1B was also correlated with ALKBH5 and Arc. Further analyses confirmed that ALKBH5 may be an independent risk factor for schizophrenia. In vitro studies, we discovered that ERVWE1 enhanced HTR1B expression, thereby activating the ERK-ELK1-Arc pathway and reducing the complexity and spine density of 5-HT neurons. Furthermore, ERVWE1 reduced m6A levels through ALKBH5 demethylation. ERVWE1 induced HTR1B upregulation by improving its mRNA stability in ALKBH5-m6A-dependent epigenetic mechanisms. Importantly, ALKBH5 mediated the observed alterations in 5-HT neuronal plasticity induced by ERVWE1. CONCLUSIONS Overall, HTR1B, Arc, and ALKBH5 levels were increased in schizophrenia and positively associated with ERVWE1. Moreover, ALKBH5 was a novel risk gene for schizophrenia. ERVWE1 impaired 5-HT neuronal plasticity in ALKBH5-m6A dependent mechanism by the HTR1B-ERK-ELK1-Arc pathway, which may be an important contributor to aberrant synaptic plasticity in schizophrenia.
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Affiliation(s)
- Xiulin Wu
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | | | - Xing Xue
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Xuhang Li
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Kexin Zhao
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Jiahang Zhang
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Wenshi Li
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Wei Yao
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Shuang Ding
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Chen Jia
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Fan Zhu
- State Key Laboratory of Virology, 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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Chilosi M, Doglioni C, Ravaglia C, Piciucchi S, Dubini A, Stefanizzi L, Poletti V. COVID-19. Biology, pathophysiology, and immunology: a pathologist view. Pathologica 2023; 115:248-256. [PMID: 38054899 DOI: 10.32074/1591-951x-954] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 10/09/2023] [Indexed: 12/07/2023] Open
Abstract
Even if the SARS-CoV-2 pandemic has been declared over, several risks and clinical problems remain to be faced, including long-COVID sequelae and possible outbreaks of pathogenic variants. Intense research on COVID-19 has provided in these few years a striking amount of data covering different fields and disciplines, which can help to provide a knowledge shield against new potential infective spreads, and may also potentially be applied to other fields of medicine, including oncology and neurology. Nevertheless, areas of uncertainty still remain regarding the pathogenic mechanisms that subtend the multifaceted manifestations of the disease. To better clarify the pathogenesis of the disease, a systematic multidisciplinary evaluation of the many mechanisms involved in COVID-19 is mandatory, including clinical, physiological, radiological, immunological and pathological studies. In COVID-19 syndrome the pathological studies have been mainly performed on autopsy cases, and only a few studies are available on biopsies. Nevertheless, these studies have provided relevant information that can substantially contribute to decipher the complex scenario characterizing the different forms of COVID-19 and long-COVID-19. In this review the data provided by pathological investigations are recapitulated and discussed, in the light of different hypothesis and data provided by clinical, physiological and immunological data.
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Affiliation(s)
- Marco Chilosi
- Department of Pathology, Pederzoli Hospital, Peschiera del Garda, Italy
| | - Claudio Doglioni
- Department of Pathology, San Raffaele Scientific Institute. Milan, Italy
| | - Claudia Ravaglia
- Department of Diseases of the Thorax, Ospedale GB Morgagni, Forlì, Italy
| | - Sara Piciucchi
- Department of Diseases of the Thorax, Ospedale GB Morgagni, Forlì, Italy
| | | | | | - Venerino Poletti
- Department of Diseases of the Thorax, Ospedale GB Morgagni, Forlì, Italy
- Department of Pathology, Ospedale GB Morgagni, Forlì, Italy
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Xue X, Wu X, Liu L, Liu L, Zhu F. ERVW-1 Activates ATF6-Mediated Unfolded Protein Response by Decreasing GANAB in Recent-Onset Schizophrenia. Viruses 2023; 15:1298. [PMID: 37376599 DOI: 10.3390/v15061298] [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: 04/28/2023] [Revised: 05/27/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Schizophrenia, a mental disorder, afflicts 1% of the worldwide population. The dysregulation of homeostasis in the endoplasmic reticulum (ER) has been implicated in schizophrenia. Moreover, recent studies indicate that ER stress and the unfolded protein response (UPR) are linked to this mental disorder. Our previous research has verified that endogenous retrovirus group W member 1 envelope (ERVW-1), a risk factor for schizophrenia, is elevated in individuals with schizophrenia. Nevertheless, no literature is available regarding the underlying relationship between ER stress and ERVW-1 in schizophrenia. The aim of our research was to investigate the molecular mechanism connecting ER stress and ERVW-1 in schizophrenia. Here, we employed Gene Differential Expression Analysis to predict differentially expressed genes (DEGs) in the human prefrontal cortex of schizophrenic patients and identified aberrant expression of UPR-related genes. Subsequent research indicated that the UPR gene called XBP1 had a positive correlation with ATF6, BCL-2, and ERVW-1 in individuals with schizophrenia using Spearman correlation analysis. Furthermore, results from the enzyme-linked immunosorbent assay (ELISA) suggested increased serum protein levels of ATF6 and XBP1 in schizophrenic patients compared with healthy controls, exhibiting a strong correlation with ERVW-1 using median analysis and Mann-Whitney U analysis. However, serum GANAB levels were decreased in schizophrenic patients compared with controls and showed a significant negative correlation with ERVW-1, ATF6, and XBP1 in schizophrenic patients. Interestingly, in vitro experiments verified that ERVW-1 indeed increased ATF6 and XBP1 expression while decreasing GANAB expression. Additionally, the confocal microscope experiment suggested that ERVW-1 could impact the shape of the ER, leading to ER stress. GANAB was found to participate in ER stress regulated by ERVW-1. In conclusion, ERVW-1 induced ER stress by suppressing GANAB expression, thereby upregulating the expression of ATF6 and XBP1 and ultimately contributing to the development of schizophrenia.
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Affiliation(s)
- Xing Xue
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071, China
| | - Xiulin Wu
- State Key Laboratory of Virology, Department of Medical Microbiology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071, China
| | - Lijuan Liu
- State Key Laboratory of Virology, 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
| | | | - Fan Zhu
- State Key Laboratory of Virology, 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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Sowa-Kućma M, Stachowicz K. Molecular Research on Mental Disorders. Int J Mol Sci 2023; 24:ijms24087104. [PMID: 37108266 PMCID: PMC10138498 DOI: 10.3390/ijms24087104] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
Mental disorders and substance use disorders affect approximately 13% of the world's population [...].
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Affiliation(s)
- Magdalena Sowa-Kućma
- Department of Human Physiology, Institute of Medical Sciences, Medical College of Rzeszow University, Kopisto Street 2a, 35-310 Rzeszow, Poland
| | - Katarzyna Stachowicz
- Department of Neurobiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, 31-343 Kraków, Poland
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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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