1
|
Solovyeva AI, Afanasev RV, Popova MA, Enukashvily NI. Dysregulation of Transposon Transcription Profiles in Cancer Cells Resembles That of Embryonic Stem Cells. Curr Issues Mol Biol 2024; 46:8576-8599. [PMID: 39194722 DOI: 10.3390/cimb46080505] [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: 07/16/2024] [Revised: 07/30/2024] [Accepted: 08/01/2024] [Indexed: 08/29/2024] Open
Abstract
Transposable elements (TEs) comprise a substantial portion of the mammalian genome, with potential implications for both embryonic development and cancer. This study aimed to characterize the expression profiles of TEs in embryonic stem cells (ESCs), cancer cell lines, tumor tissues, and the tumor microenvironment (TME). We observed similarities in TE expression profiles between cancer cells and ESCs, suggesting potential parallels in regulatory mechanisms. Notably, four TE RNAs (HERVH, LTR7, HERV-Fc1, HERV-Fc2) exhibited significant downregulation across cancer cell lines and tumor tissues compared to ESCs, highlighting potential roles in pluripotency regulation. The strong up-regulation of the latter two TEs (HERV-Fc1, HERV-Fc2) in ESCs has not been previously demonstrated and may be a first indication of their role in the regulation of pluripotency. Conversely, tandemly repeated sequences (MSR1, CER, ALR) showed up-regulation in cancer contexts. Moreover, a difference in TE expression was observed between the TME and the tumor bulk transcriptome, with distinct dysregulated TE profiles. Some TME-specific TEs were absent in normal tissues, predominantly belonging to LTR and L1 retrotransposon families. These findings not only shed light on the regulatory roles of TEs in both embryonic development and cancer but also suggest novel targets for anti-cancer therapy. Understanding the interplay between cancer cells and the TME at the TE level may pave the way for further research into therapeutic interventions.
Collapse
Affiliation(s)
- Anna I Solovyeva
- Lab of the Non-Coding DNA Studies, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
- Zoological Institute of Russian Academy of Sciences, 199034 St. Petersburg, Russia
| | - Roman V Afanasev
- Lab of the Non-Coding DNA Studies, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | - Marina A Popova
- Lab of the Non-Coding DNA Studies, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
- Applied Genomics Laboratory, SCAMT Institute, ITMO University, 191002 St. Petersburg, Russia
| | - Natella I Enukashvily
- Lab of the Non-Coding DNA Studies, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
- Department of Cytology and Histology, St. Petersburg State University, 199034 St. Petersburg, Russia
| |
Collapse
|
2
|
Kassiotis G, Stoye JP. Making a virtue of necessity: the pleiotropic role of human endogenous retroviruses in cancer. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0277. [PMID: 28893944 PMCID: PMC5597744 DOI: 10.1098/rstb.2016.0277] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2017] [Indexed: 12/18/2022] Open
Abstract
Like all other mammals, humans harbour an astonishing number of endogenous retroviruses (ERVs), as well as other retroelements, embedded in their genome. These remnants of ancestral germline infection with distinct exogenous retroviruses display various degrees of open reading frame integrity and replication capability. Modern day exogenous retroviruses, as well as the infectious predecessors of ERVs, are demonstrably oncogenic. Further, replication-competent ERVs continue to cause cancers in many other species of mammal. Moreover, human cancers are characterized by transcriptional activation of human endogenous retroviruses (HERVs). These observations conspire to incriminate HERVs as causative agents of human cancer. However, exhaustive investigation of cancer genomes suggests that HERVs have entirely lost the ability for re-infection and thus the potential for insertional mutagenic activity. Although there may be non-insertional mechanisms by which HERVs contribute to cancer development, recent evidence also uncovers potent anti-tumour activities exerted by HERV replication intermediates or protein products. On balance, it appears that HERVs, despite their oncogenic past, now represent potential targets for immune-mediated anti-tumour mechanisms. This article is part of the themed issue ‘Human oncogenic viruses’.
Collapse
Affiliation(s)
- George Kassiotis
- Retroviral Immunology, The Francis Crick Institute, London, UK .,Department of Medicine, Faculty of Medicine, Imperial College London, London, UK
| | - Jonathan P Stoye
- Retrovirus-Host Interactions, The Francis Crick Institute, London, UK .,Department of Medicine, Faculty of Medicine, Imperial College London, London, UK
| |
Collapse
|
3
|
Lee HE, Ayarpadikannan S, Kim HS. Role of transposable elements in genomic rearrangement, evolution, gene regulation and epigenetics in primates. Genes Genet Syst 2015; 90:245-57. [DOI: 10.1266/ggs.15-00016] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Hee-Eun Lee
- Department of Biological Sciences, College of Natural Sciences, Pusan National University
- Genetic Engineering Institute, Pusan National University
| | - Selvam Ayarpadikannan
- Department of Biological Sciences, College of Natural Sciences, Pusan National University
| | - Heui-Soo Kim
- Department of Biological Sciences, College of Natural Sciences, Pusan National University
- Genetic Engineering Institute, Pusan National University
| |
Collapse
|
4
|
Li L, Lorzadeh A, Hirst M. Regulatory variation: an emerging vantage point for cancer biology. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2013; 6:37-59. [DOI: 10.1002/wsbm.1250] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Luolan Li
- Centre for High-Throughput Biology, Department of Microbiology & Immunology; University of British Columbia; Vancouver, British Columbia Canada
| | - Alireza Lorzadeh
- Centre for High-Throughput Biology, Department of Microbiology & Immunology; University of British Columbia; Vancouver, British Columbia Canada
| | - Martin Hirst
- Centre for High-Throughput Biology, Department of Microbiology & Immunology; University of British Columbia; Vancouver, British Columbia Canada
- Canada's Michael Smith Genome Sciences Centre; BC Cancer Agency; Vancouver, British Columbia Canada
| |
Collapse
|
5
|
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.
Collapse
Affiliation(s)
- Hong-Lian Yu
- Department of Medical Microbiology, School of Medicine, Wuhan University, Wuhan, Hubei 430071, PR China
| | | | | |
Collapse
|
6
|
Jung YD, Ahn K, Kim YJ, Bae JH, Lee JR, Kim HS. Retroelements: molecular features and implications for disease. Genes Genet Syst 2013; 88:31-43. [PMID: 23676708 DOI: 10.1266/ggs.88.31] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Eukaryotic genomes comprise numerous retroelements that have a major impact on the structure and regulation of gene function. Retroelements are regulated by epigenetic controls, and they generate multiple miRNAs that are involved in the induction and progression of genomic instability. Elucidation of the biological roles of retroelements deserves continuous investigation to better understand their evolutionary features and implications for disease.
Collapse
Affiliation(s)
- Yi-Deun Jung
- Department of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea
| | | | | | | | | | | |
Collapse
|
7
|
HERV-E-mediated modulation of PLA2G4A transcription in urothelial carcinoma. PLoS One 2012; 7:e49341. [PMID: 23145155 PMCID: PMC3492278 DOI: 10.1371/journal.pone.0049341] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 10/09/2012] [Indexed: 12/30/2022] Open
Abstract
Human endogenous retroviruses (HERV) and related elements account for more than 8% of the human genome and significantly contribute to the human transcriptome by long terminal repeat (LTR) promoter activity. In this context, HERVs are thought to intervene in the expression of adjacent genes by providing regulatory sequences (cis-effect) or via noncoding RNA including natural antisense transcripts. To address the potential impact of HERV activity in urothelial carcinoma, we comparatively analyzed the HERV transcription profiles in paired samples of non-malignant urothelium and urothelial carcinoma derived from 13 patients with bladder cancer by means of a retrovirus-specific microarray (RetroArray). We established a characteristic HERV signature consisting of six ubiquitously active HERV subgroups (E4-1, HERV-Rb, ERV9, HERV-K-T47D, NMWV3, HERV-KC4). The transcription pattern is largely identical in human urothelial carcinoma, non-malignant urothelial tissue, four tumor-derived cell lines and in a non-malignant urothelial cell line (UROtsa). Quantitative reverse transcriptase PCR (qRT-PCR) of HERV-E4-1, HERV-K(HML-6) and HERV-T(S71-TK1) revealed a bias to lower HERV activity in carcinoma samples compared to non-malignant tissue. Determination of active HERV-E4-1 loci by cloning and sequencing revealed six HERV-E4-1 proviral loci that are differentially regulated in urothelial carcinoma cells and normal tissue. Two full-length HERV-E4-1 proviruses, HERV-Ec1 and HERV-Ec6, are located in antisense orientation in introns of the genes PLA2G4A and RNGTT, respectively. PLA2G4A encodes a cytosolic phospholipase A2 (cPLA2) that is dysregulated in many human tumors. PLA2G4A and HERV-Ec1 displayed reciprocal transcript levels in 7 of 11 urothelial carcinoma patients. Moreover, reciprocal shifts were observed after treatment of UROtsa cells with HERV-Ec1 and PLA2G4A-directed siRNAs or 5-aza-2′-deoxycytidine (aza-dC) pointing to an antagonistic regulation of PLA2G4A and HERV-Ec1 transcription in human urothelial cells. We suggest that transcription of HERV-Ec1 contributes to fine tuning of cPLA2 expression, thereby facilitating tumorigenesis.
Collapse
|
8
|
Kines KJ, Belancio VP. Expressing genes do not forget their LINEs: transposable elements and gene expression. FRONT BIOSCI-LANDMRK 2012; 17:1329-44. [PMID: 22201807 DOI: 10.2741/3990] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Historically the accumulated mass of mammalian transposable elements (TEs), particularly those located within gene boundaries, was viewed as a genetic burden potentially detrimental to the genomic landscape. This notion has been strengthened by the discovery that transposable sequences can alter the architecture of the transcriptome, not only through insertion, but also long after the integration process is completed. Insertions previously considered harmless are now known to impact the expression of host genes via modification of the transcript quality or quantity, transcriptional interference, or by the control of pathways that affect the mRNA life-cycle. Conversely, several examples of the evolutionary advantageous impact of TEs on the host gene structure that diversified the cellular transcriptome are reported. TE-induced changes in gene expression can be tissue- or disease-specific, raising the possibility that the impact of TE sequences may vary during development, among normal cell types, and between normal and disease-affected tissues. The understanding of the rules and abundance of TE-interference with gene expression is in its infancy, and its contribution to human disease and/or evolution remains largely unexplored.
Collapse
Affiliation(s)
- Kristine J Kines
- Department of Structural and Cellular Biology, Tulane University School of Medicine, Tulane University Cancer Center and Tulane Center for Aging
| | | |
Collapse
|
9
|
Sin HS, Koh E, Kim DS, Murayama M, Sugimoto K, Maeda Y, Yoshida A, Namiki M. Human endogenous retrovirus K14C drove genomic diversification of the Y chromosome during primate evolution. J Hum Genet 2010; 55:717-25. [DOI: 10.1038/jhg.2010.94] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
10
|
Romanish MT, Cohen CJ, Mager DL. Potential mechanisms of endogenous retroviral-mediated genomic instability in human cancer. Semin Cancer Biol 2010; 20:246-53. [PMID: 20685251 DOI: 10.1016/j.semcancer.2010.05.005] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 05/12/2010] [Accepted: 05/19/2010] [Indexed: 01/13/2023]
Abstract
Malignancy results from a complex combination of genetic and epigenetic changes, the full effects of which are still largely unknown. Here we summarize current knowledge of the origin, retrotranspositional activity, epigenetic state, and transcription of human endogenous retroviruses (HERVs), and then discuss the potential effects of their deregulation in cancer. Evidence suggests that cancer-associated epigenetic changes most likely underlie potential HERV-mediated effects on genome and transcriptome instability and may play a role in malignancy. Despite our currently limited understanding of the importance of HERVs or other transposable elements in cancer development, we believe that the emerging era of high-throughput sequencing of cancer genomes, epigenomes, and transcriptomes will provide unprecedented opportunities to investigate these roles in the future.
Collapse
Affiliation(s)
- M T Romanish
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, BC, Canada.
| | | | | |
Collapse
|
11
|
Cooperative exonization of MaLR and AluJo elements contributed an alternative promoter and novel splice variants of RNF19. Gene 2008; 424:63-70. [PMID: 18721867 DOI: 10.1016/j.gene.2008.07.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 07/01/2008] [Accepted: 07/28/2008] [Indexed: 11/22/2022]
Abstract
The RNF19 protein, which contains RING-finger and IBR motifs, acts as an E3 ubiquitin ligase localized to Lewy bodies. RNF19 is located on human chromosome 8q22.2, has a 4.4-kb transcript, and is ubiquitously expressed in various tissues. Here, we identified an alternative RNF19 promoter region and alternative RNF19 transcripts derived from MaLR (mammalian apparent LTR-retrotransposon) and AluJo elements. Comparative analyses indicated human-specific expression of the MaLR- and AluJo-related transcripts. From the expression analysis of 72 tissue samples including human normal, tumor, and primate tissues, three different isoforms (V1, V2, and V3) of MaLR-derived transcripts were identified. Quantitative RT-PCR analysis showed a dominant expression pattern of the V2 MaLR-derived transcript. A reporter gene assay for MaLR element promoter activity indicated that pGL2-RNF19/MaLR in the forward orientation is capable of driving luciferase gene expression in Cos7 and HCT116 cells. These findings suggest that RNF19 has acquired a new promoter and alternative exons via continuous retrotransposition events of MaLR and AluJo elements during mammalian and primate evolution, respectively.
Collapse
|
12
|
Kim YJ, Huh JW, Kim DS, Bae MI, Lee JR, Ha HS, Ahn K, Kim TO, Song GA, Kim HS. Molecular characterization of the DYX1C1 gene and its application as a cancer biomarker. J Cancer Res Clin Oncol 2008; 135:265-70. [PMID: 18618141 DOI: 10.1007/s00432-008-0445-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 06/25/2008] [Indexed: 12/19/2022]
Abstract
PURPOSE DYX1C1 has three alternatively spliced transcripts. Therefore, we expect that alternative transcripts of DYX1C1 are used as a biomarker to detect specific cancer. METHODS RT-PCR analysis is conducted in order to detect expression of the DYX1C1 gene and the PCR products were analyzed using the Image J program to compare the expression levels of each transcript. RESULTS We found one of the transcripts was directly associated with an HERV-H LTR element that could be translated into protein sequence. Four new alternative transcripts were identified by RT-PCR analysis with various human tissue samples including 10 normal and adjacent tumor tissue sets. Semi-quantitative RT-PCR analysis showed the transcriptional activity of V3 and V2 was higher in tumor than in normal tissue samples, especially in the colorectal tissue samples. CONCLUSION Our results indicated that alternatively spliced transcript variants of the DYX1C1 gene could be used as cancer biomarkers to detect colorectal cancer.
Collapse
Affiliation(s)
- Yun-Ji Kim
- Division of Biological Sciences, College of Natural Sciences, Pusan National University, Busan, 609-735, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|