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Hu Z, Guo X, Li Z, Meng Z, Huang S. The neoantigens derived from transposable elements - A hidden treasure for cancer immunotherapy. Biochim Biophys Acta Rev Cancer 2024; 1879:189126. [PMID: 38849060 DOI: 10.1016/j.bbcan.2024.189126] [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: 01/16/2024] [Revised: 05/26/2024] [Accepted: 06/02/2024] [Indexed: 06/09/2024]
Abstract
Neoantigen-based therapy is a promising approach that selectively activates the immune system of the host to recognize and eradicate cancer cells. Preliminary clinical trials have validated the feasibility, safety, and immunogenicity of personalized neoantigen-directed vaccines, enhancing their effectiveness and broad applicability in immunotherapy. While many ongoing oncological trials concentrate on neoantigens derived from mutations, these targets do not consistently provoke an immune response in all patients harboring the mutations. Additionally, tumors like ovarian cancer, which have a low tumor mutational burden (TMB), may be less amenable to mutation-based neoantigen therapies. Recent advancements in next-generation sequencing and bioinformatics have uncovered a rich source of neoantigens from non-canonical RNAs associated with transposable elements (TEs). Considering the substantial presence of TEs in the human genome and the proven immunogenicity of TE-derived neoantigens in various tumor types, this review investigates the latest findings on TE-derived neoantigens, examining their clinical implications, challenges, and unique advantages in enhancing tumor immunotherapy.
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Affiliation(s)
- Zhixiang Hu
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xinyi Guo
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Ziteng Li
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhiqiang Meng
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
| | - Shenglin Huang
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
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2
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Lee AV, Nestler KA, Chiappinelli KB. Therapeutic targeting of DNA methylation alterations in cancer. Pharmacol Ther 2024; 258:108640. [PMID: 38570075 DOI: 10.1016/j.pharmthera.2024.108640] [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: 12/13/2023] [Revised: 03/13/2024] [Accepted: 03/22/2024] [Indexed: 04/05/2024]
Abstract
DNA methylation is a critical component of gene regulation and plays an important role in the development of cancer. Hypermethylation of tumor suppressor genes and silencing of DNA repair pathways facilitate uncontrolled cell growth and synergize with oncogenic mutations to perpetuate cancer phenotypes. Additionally, aberrant DNA methylation hinders immune responses crucial for antitumor immunity. Thus, inhibiting dysregulated DNA methylation is a promising cancer therapy. Pharmacologic inhibition of DNA methylation reactivates silenced tumor suppressors and bolster immune responses through induction of viral mimicry. Now, with the advent of immunotherapies and discovery of the immune-modulatory effects of DNA methylation inhibitors, there is great interest in understanding how targeting DNA methylation in combination with other therapies can enhance antitumor immunity. Here, we describe the role of aberrant DNA methylation in cancer and mechanisms by which it promotes tumorigenesis and modulates immune responses. Finally, we review the initial discoveries and ongoing efforts to target DNA methylation as a cancer therapeutic.
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Affiliation(s)
- Abigail V Lee
- Department of Microbiology, Immunology, & Tropical Medicine, The George Washington University, Washington, DC, USA
| | - Kevin A Nestler
- Department of Microbiology, Immunology, & Tropical Medicine, The George Washington University, Washington, DC, USA
| | - Katherine B Chiappinelli
- Department of Microbiology, Immunology, & Tropical Medicine, The George Washington University, Washington, DC, USA.
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3
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Yoon B, Kim H, Jung SW, Park J. Single-cell lineage tracing approaches to track kidney cell development and maintenance. Kidney Int 2024; 105:1186-1199. [PMID: 38554991 DOI: 10.1016/j.kint.2024.01.045] [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: 09/08/2023] [Revised: 12/06/2023] [Accepted: 01/09/2024] [Indexed: 04/02/2024]
Abstract
The kidney is a complex organ consisting of various cell types. Previous studies have aimed to elucidate the cellular relationships among these cell types in developing and mature kidneys using Cre-loxP-based lineage tracing. However, this methodology falls short of fully capturing the heterogeneous nature of the kidney, making it less than ideal for comprehensively tracing cellular progression during kidney development and maintenance. Recent technological advancements in single-cell genomics have revolutionized lineage tracing methods. Single-cell lineage tracing enables the simultaneous tracing of multiple cell types within complex tissues and their transcriptomic profiles, thereby allowing the reconstruction of their lineage tree with cell state information. Although single-cell lineage tracing has been successfully applied to investigate cellular hierarchies in various organs and tissues, its application in kidney research is currently lacking. This review comprehensively consolidates the single-cell lineage tracing methods, divided into 4 categories (clustered regularly interspaced short palindromic repeat [CRISPR]/CRISPR-associated protein 9 [Cas9]-based, transposon-based, Polylox-based, and native barcoding methods), and outlines their technical advantages and disadvantages. Furthermore, we propose potential future research topics in kidney research that could benefit from single-cell lineage tracing and suggest suitable technical strategies to apply to these topics.
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Affiliation(s)
- Baul Yoon
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Hayoung Kim
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Su Woong Jung
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Kyung Hee University, Seoul, Republic of Korea; Division of Nephrology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea.
| | - Jihwan Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea.
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4
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Kojima S. Investigating mobile element variations by statistical genetics. Hum Genome Var 2024; 11:23. [PMID: 38816353 PMCID: PMC11140006 DOI: 10.1038/s41439-024-00280-1] [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: 01/31/2024] [Revised: 04/17/2024] [Accepted: 04/24/2024] [Indexed: 06/01/2024] Open
Abstract
The integration of structural variations (SVs) in statistical genetics provides an opportunity to understand the genetic factors influencing complex human traits and disease. Recent advances in long-read technology and variant calling methods for short reads have improved the accurate discovery and genotyping of SVs, enabling their use in expression quantitative trait loci (eQTL) analysis and genome-wide association studies (GWAS). Mobile elements are DNA sequences that insert themselves into various genome locations. Insertional polymorphisms of mobile elements between humans, called mobile element variations (MEVs), contribute to approximately 25% of human SVs. We recently developed a variant caller that can accurately identify and genotype MEVs from biobank-scale short-read whole-genome sequencing (WGS) datasets and integrate them into statistical genetics. The use of MEVs in eQTL analysis and GWAS has a minimal impact on the discovery of genome loci associated with gene expression and disease; most disease-associated haplotypes can be identified by single nucleotide variations (SNVs). On the other hand, it helps make hypotheses about causal variants or effector variants. Focusing on MEVs, we identified multiple MEVs that contribute to differential gene expression and one of them is a potential cause of skin disease, emphasizing the importance of the integration of MEVs in medical genetics. Here, I will provide an overview of MEVs, MEV calling from WGS, and the integration of MEVs in statistical genetics. Finally, I will discuss the unanswered questions about MEVs, such as rare variants.
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Affiliation(s)
- Shohei Kojima
- Genome Immunobiology RIKEN Hakubi Research Team, RIKEN Center for Integrative Medical Sciences, Yokohama, 230-0045, Japan.
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5
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Lee KH, Kim J, Kim JH. 3D epigenomics and 3D epigenopathies. BMB Rep 2024; 57:216-231. [PMID: 38627948 PMCID: PMC11139681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/15/2024] [Accepted: 03/18/2024] [Indexed: 05/25/2024] Open
Abstract
Mammalian genomes are intricately compacted to form sophisticated 3-dimensional structures within the tiny nucleus, so called 3D genome folding. Despite their shapes reminiscent of an entangled yarn, the rapid development of molecular and next-generation sequencing technologies (NGS) has revealed that mammalian genomes are highly organized in a hierarchical order that delicately affects transcription activities. An increasing amount of evidence suggests that 3D genome folding is implicated in diseases, giving us a clue on how to identify novel therapeutic approaches. In this review, we will study what 3D genome folding means in epigenetics, what types of 3D genome structures there are, how they are formed, and how the technologies have developed to explore them. We will also discuss the pathological implications of 3D genome folding. Finally, we will discuss how to leverage 3D genome folding and engineering for future studies. [BMB Reports 2024; 57(5): 216-231].
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Affiliation(s)
- Kyung-Hwan Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Jungyu Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Ji Hun Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
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6
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Li Y, Shen S, Guo H, Li H, Zhang L, Zhang B, Yu XF, Wei W. Pharmacological inhibition of neddylation impairs long interspersed element 1 retrotransposition. Cell Rep 2024; 43:113749. [PMID: 38329876 DOI: 10.1016/j.celrep.2024.113749] [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: 06/14/2023] [Revised: 09/25/2023] [Accepted: 01/23/2024] [Indexed: 02/10/2024] Open
Abstract
Aberrant long interspersed element 1 (LINE-1 or L1) activity can cause insertional mutagenesis and chromosomal rearrangements and has been detected in several types of cancers. Here, we show that neddylation, a post-translational modification process, is essential for L1 transposition. The antineoplastic drug MLN4924 is an L1 inhibitor that suppresses NEDD8-activating enzyme activity. Neddylation inhibition by MLN4924 selectively impairs ORF2p-mediated L1 reverse transcription and blocks the generation of L1 cDNA. Consistent with these results, MLN4924 treatment suppresses the retrotransposition activity of the non-autonomous retrotransposons short interspersed nuclear element R/variable number of tandem repeat/Alu and Alu, which rely on the reverse transcription activity of L1 ORF2p. The E2 enzyme UBE2M in the neddylation pathway, rather than UBE2F, is required for L1 ORF2p and retrotransposition. Interference with the functions of certain neddylation-dependent Cullin-really interesting new gene E3 ligases disrupts L1 reverse transcription and transposition activity. Our findings provide insights into the regulation of L1 retrotransposition and the identification of therapeutic targets for L1 dysfunctions.
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Affiliation(s)
- Yan Li
- Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education, Institute of Translational Medicine, First Hospital, Jilin University, Changchun, Jilin 130021, China; Department of Pathology, The First Bethune Hospital of Jilin University, Changchun, China
| | - Siyu Shen
- Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education, Institute of Translational Medicine, First Hospital, Jilin University, Changchun, Jilin 130021, China
| | - Haoran Guo
- Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education, Institute of Translational Medicine, First Hospital, Jilin University, Changchun, Jilin 130021, China
| | - Huili Li
- Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education, Institute of Translational Medicine, First Hospital, Jilin University, Changchun, Jilin 130021, China
| | - Lili Zhang
- Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education, Institute of Translational Medicine, First Hospital, Jilin University, Changchun, Jilin 130021, China
| | - Boyin Zhang
- Department of Orthopedics Surgery, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - Xiao-Fang Yu
- Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, China National Ministry of Education), The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310000, China; Cancer Center, Zhejiang University, Hangzhou, Zhejiang 310000, China
| | - Wei Wei
- Key Laboratory of Organ Regeneration and Transplantation of Ministry of Education, Institute of Translational Medicine, First Hospital, Jilin University, Changchun, Jilin 130021, China; Institute of Virology and AIDS Research, First Hospital, Jilin University, Changchun, Jilin 130021, China.
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7
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Perkiö A, Pradhan B, Genc F, Pirttikoski A, Pikkusaari S, Erkan EP, Falco MM, Huhtinen K, Narva S, Hynninen J, Kauppi L, Vähärautio A. Locus-specific LINE-1 expression in clinical ovarian cancer specimens at the single-cell level. Sci Rep 2024; 14:4322. [PMID: 38383551 PMCID: PMC10881972 DOI: 10.1038/s41598-024-54113-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 02/08/2024] [Indexed: 02/23/2024] Open
Abstract
Long interspersed nuclear elements (LINE-1s/L1s) are a group of retrotransposons that can copy themselves within a genome. In humans, it is the most successful transposon in nucleotide content. L1 expression is generally mild in normal human tissues, but the activity has been shown to increase significantly in many cancers. Few studies have examined L1 expression at single-cell resolution, thus it is undetermined whether L1 reactivation occurs solely in malignant cells within tumors. One of the cancer types with frequent L1 activity is high-grade serous ovarian carcinoma (HGSOC). Here, we identified locus-specific L1 expression with 3' single-cell RNA sequencing in pre- and post-chemotherapy HGSOC sample pairs from 11 patients, and in fallopian tube samples from five healthy women. Although L1 expression quantification with the chosen technique was challenging due to the repetitive nature of the element, we found evidence of L1 expression primarily in cancer cells, but also in other cell types, e.g. cancer-associated fibroblasts. The expression levels were similar in samples taken before and after neoadjuvant chemotherapy, indicating that L1 transcriptional activity was unaffected by clinical platinum-taxane treatment. Furthermore, L1 activity was negatively associated with the expression of MYC target genes, a finding that supports earlier literature of MYC being an L1 suppressor.
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Affiliation(s)
- Anna Perkiö
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
| | - Barun Pradhan
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
- New York Genome Center, New York, NY, USA
| | - Fatih Genc
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
| | - Anna Pirttikoski
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
| | - Sanna Pikkusaari
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
| | - Erdogan Pekcan Erkan
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Matias Marin Falco
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
| | - Kaisa Huhtinen
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
- Institute of Biomedicine and FICAN West Cancer Centre, University of Turku and Turku University Hospital, 20521, Turku, Finland
| | - Sara Narva
- Department of Obstetrics and Gynecology, University of Turku and Turku University Hospital, 20521, Turku, Finland
| | - Johanna Hynninen
- Department of Obstetrics and Gynecology, University of Turku and Turku University Hospital, 20521, Turku, Finland
| | - Liisa Kauppi
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland.
| | - Anna Vähärautio
- Research Program in Systems Oncology, Research Programs Unit, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland.
- Foundation for the Finnish Cancer Institute (FCI), Helsinki, Finland.
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8
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Lanciano S, Philippe C, Sarkar A, Pratella D, Domrane C, Doucet AJ, van Essen D, Saccani S, Ferry L, Defossez PA, Cristofari G. Locus-level L1 DNA methylation profiling reveals the epigenetic and transcriptional interplay between L1s and their integration sites. CELL GENOMICS 2024; 4:100498. [PMID: 38309261 PMCID: PMC10879037 DOI: 10.1016/j.xgen.2024.100498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/20/2023] [Accepted: 01/09/2024] [Indexed: 02/05/2024]
Abstract
Long interspersed element 1 (L1) retrotransposons are implicated in human disease and evolution. Their global activity is repressed by DNA methylation, but deciphering the regulation of individual copies has been challenging. Here, we combine short- and long-read sequencing to unveil L1 methylation heterogeneity across cell types, families, and individual loci and elucidate key principles involved. We find that the youngest primate L1 families are specifically hypomethylated in pluripotent stem cells and the placenta but not in most tumors. Locally, intronic L1 methylation is intimately associated with gene transcription. Conversely, the L1 methylation state can propagate to the proximal region up to 300 bp. This phenomenon is accompanied by the binding of specific transcription factors, which drive the expression of L1 and chimeric transcripts. Finally, L1 hypomethylation alone is typically insufficient to trigger L1 expression due to redundant silencing pathways. Our results illuminate the epigenetic and transcriptional interplay between retrotransposons and their host genome.
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Affiliation(s)
- Sophie Lanciano
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - Claude Philippe
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - Arpita Sarkar
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - David Pratella
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - Cécilia Domrane
- University Paris Cité, CNRS, Epigenetics and Cell Fate, Paris, France
| | - Aurélien J Doucet
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - Dominic van Essen
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - Simona Saccani
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - Laure Ferry
- University Paris Cité, CNRS, Epigenetics and Cell Fate, Paris, France
| | | | - Gael Cristofari
- University Cote d'Azur, INSERM, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France.
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9
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Ramirez P, Sun W, Kazempour Dehkordi S, Zare H, Fongang B, Bieniek KF, Frost B. Nanopore-based DNA long-read sequencing analysis of the aged human brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.01.578450. [PMID: 38370753 PMCID: PMC10871260 DOI: 10.1101/2024.02.01.578450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Aging disrupts cellular processes such as DNA repair and epigenetic control, leading to a gradual buildup of genomic alterations that can have detrimental effects in post-mitotic cells. Genomic alterations in regions of the genome that are rich in repetitive sequences, often termed "dark loci," are difficult to resolve using traditional sequencing approaches. New long-read technologies offer promising avenues for exploration of previously inaccessible regions of the genome. Using nanopore-based long-read whole-genome sequencing of DNA extracted from aged 18 human brains, we identify previously unreported structural variants and methylation patterns within repetitive DNA, focusing on transposable elements ("jumping genes") as crucial sources of variation, particularly in dark loci. Our analyses reveal potential somatic insertion variants and provides DNA methylation frequencies for many retrotransposon families. We further demonstrate the utility of this technology for the study of these challenging genomic regions in brains affected by Alzheimer's disease and identify significant differences in DNA methylation in pathologically normal brains versus those affected by Alzheimer's disease. Highlighting the power of this approach, we discover specific polymorphic retrotransposons with altered DNA methylation patterns. These retrotransposon loci have the potential to contribute to pathology, warranting further investigation in Alzheimer's disease research. Taken together, our study provides the first long-read DNA sequencing-based analysis of retrotransposon sequences, structural variants, and DNA methylation in the aging brain affected with Alzheimer's disease neuropathology.
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Affiliation(s)
- Paulino Ramirez
- Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio, San Antonio, Texas
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas
| | - Wenyan Sun
- Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio, San Antonio, Texas
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas
- School of Pharmacy, University of Missouri-Kansas City, Kansas City, Missouri
| | - Shiva Kazempour Dehkordi
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas
| | - Habil Zare
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas
| | - Bernard Fongang
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Biochemistry & Structural Biology, University of Texas Health San Antonio, San Antonio, Texas
| | - Kevin F. Bieniek
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Pathology, University of Texas Health San Antonio, San Antonio, Texas
| | - Bess Frost
- Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio, San Antonio, Texas
- Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, Texas
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas
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10
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Lu X, Liu L. Genome stability from the perspective of telomere length. Trends Genet 2024; 40:175-186. [PMID: 37957036 DOI: 10.1016/j.tig.2023.10.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023]
Abstract
Telomeres and their associated proteins protect the ends of chromosomes to maintain genome stability. Telomeres undergo progressive shortening with each cell division in mammalian somatic cells without telomerase, resulting in genome instability. When telomeres reach a critically short length or are recognized as a damage signal, cells enter a state of senescence, followed by cell cycle arrest, programmed cell death, or immortalization. This review provides an overview of recent advances in the intricate relationship between telomeres and genome instability. Alongside well-established mechanisms such as chromosomal fusion and telomere fusion, we will delve into the perspective on genome stability by examining the role of retrotransposons. Retrotransposons represent an emerging pathway to regulate genome stability through their interactions with telomeres.
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Affiliation(s)
- Xinyi Lu
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, Tianjin 300350, China.
| | - Lin Liu
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, Tianjin 300350, China; Frontiers Science Center for Cell Responses, College of Life Science, Nankai University, Tianjin, Tianjin 300071, China; Haihe Laboratory of Cell Ecosystem, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, China; Institute of Translational Medicine, Tianjin Union Medical Center, Nankai University, Tianjin 300000, China.
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11
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Liang Y, Qu X, Shah NM, Wang T. Towards targeting transposable elements for cancer therapy. Nat Rev Cancer 2024; 24:123-140. [PMID: 38228901 DOI: 10.1038/s41568-023-00653-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/04/2023] [Indexed: 01/18/2024]
Abstract
Transposable elements (TEs) represent almost half of the human genome. Historically deemed 'junk DNA', recent technological advancements have stimulated a wave of research into the functional impact of TEs on gene-regulatory networks in evolution and development, as well as in diseases including cancer. The genetic and epigenetic evolution of cancer involves the exploitation of TEs, whereby TEs contribute directly to cancer-specific gene activities. This Review provides a perspective on the role of TEs in cancer as being a 'double-edged sword', both promoting cancer evolution and representing a vulnerability that could be exploited in cancer therapy. We discuss how TEs affect transcriptome regulation and other cellular processes in cancer. We highlight the potential of TEs as therapeutic targets for cancer. We also summarize technical hurdles in the characterization of TEs with genomic assays. Last, we outline open questions and exciting future research avenues.
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Affiliation(s)
- Yonghao Liang
- Department of Genetics, Washington University School of Medicine, Saint Louis, MO, USA
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Xuan Qu
- Department of Genetics, Washington University School of Medicine, Saint Louis, MO, USA
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Nakul M Shah
- Division of Cancer Medicine, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ting Wang
- Department of Genetics, Washington University School of Medicine, Saint Louis, MO, USA.
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, Saint Louis, MO, USA.
- McDonnell Genome Institute, Washington University School of Medicine, Saint Louis, MO, USA.
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12
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Mendez-Dorantes C, Burns KH. LINE-1 retrotransposition and its deregulation in cancers: implications for therapeutic opportunities. Genes Dev 2023; 37:948-967. [PMID: 38092519 PMCID: PMC10760644 DOI: 10.1101/gad.351051.123] [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] [Indexed: 12/28/2023]
Abstract
Long interspersed element 1 (LINE-1) is the only protein-coding transposon that is active in humans. LINE-1 propagates in the genome using RNA intermediates via retrotransposition. This activity has resulted in LINE-1 sequences occupying approximately one-fifth of our genome. Although most copies of LINE-1 are immobile, ∼100 copies are retrotransposition-competent. Retrotransposition is normally limited via epigenetic silencing, DNA repair, and other host defense mechanisms. In contrast, LINE-1 overexpression and retrotransposition are hallmarks of cancers. Here, we review mechanisms of LINE-1 regulation and how LINE-1 may promote genetic heterogeneity in tumors. Finally, we discuss therapeutic strategies to exploit LINE-1 biology in cancers.
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Affiliation(s)
- Carlos Mendez-Dorantes
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA;
- Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142, USA
| | - Kathleen H Burns
- Department of Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA;
- Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142, USA
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13
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Rybacki K, Xia M, Ahsan MU, Xing J, Wang K. Assessing the Expression of Long INterspersed Elements (LINEs) via Long-Read Sequencing in Diverse Human Tissues and Cell Lines. Genes (Basel) 2023; 14:1893. [PMID: 37895242 PMCID: PMC10606529 DOI: 10.3390/genes14101893] [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: 09/04/2023] [Revised: 09/21/2023] [Accepted: 09/27/2023] [Indexed: 10/29/2023] Open
Abstract
Transposable elements, such as Long INterspersed Elements (LINEs), are DNA sequences that can replicate within genomes. LINEs replicate using an RNA intermediate followed by reverse transcription and are typically a few kilobases in length. LINE activity creates genomic structural variants in human populations and leads to somatic alterations in cancer genomes. Long-read RNA sequencing technologies, including Oxford Nanopore and PacBio, can directly sequence relatively long transcripts, thus providing the opportunity to examine full-length LINE transcripts. This study focuses on the development of a new bioinformatics pipeline for the identification and quantification of active, full-length LINE transcripts in diverse human tissues and cell lines. In our pipeline, we utilized RepeatMasker to identify LINE-1 (L1) transcripts from long-read transcriptome data and incorporated several criteria, such as transcript start position, divergence, and length, to remove likely false positives. Comparisons between cancerous and normal cell lines, as well as human tissue samples, revealed elevated expression levels of young LINEs in cancer, particularly at intact L1 loci. By employing bioinformatics methodologies on long-read transcriptome data, this study demonstrates the landscape of L1 expression in tissues and cell lines.
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Affiliation(s)
- Karleena Rybacki
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA; (K.R.); (M.X.)
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
| | - Mingyi Xia
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA; (K.R.); (M.X.)
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
| | - Mian Umair Ahsan
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
| | - Jinchuan Xing
- Department of Genetics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
- Human Genetics Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Kai Wang
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA; (K.R.); (M.X.)
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
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14
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Gerdes P, Chan D, Lundberg M, Sanchez-Luque FJ, Bodea GO, Ewing AD, Faulkner GJ, Richardson SR. Locus-resolution analysis of L1 regulation and retrotransposition potential in mouse embryonic development. Genome Res 2023; 33:1465-1481. [PMID: 37798118 PMCID: PMC10620060 DOI: 10.1101/gr.278003.123] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/21/2023] [Indexed: 10/07/2023]
Abstract
Mice harbor ∼2800 intact copies of the retrotransposon Long Interspersed Element 1 (L1). The in vivo retrotransposition capacity of an L1 copy is defined by both its sequence integrity and epigenetic status, including DNA methylation of the monomeric units constituting young mouse L1 promoters. Locus-specific L1 methylation dynamics during development may therefore elucidate and explain spatiotemporal niches of endogenous retrotransposition but remain unresolved. Here, we interrogate the retrotransposition efficiency and epigenetic fate of source (donor) L1s, identified as mobile in vivo. We show that promoter monomer loss consistently attenuates the relative retrotransposition potential of their offspring (daughter) L1 insertions. We also observe that most donor/daughter L1 pairs are efficiently methylated upon differentiation in vivo and in vitro. We use Oxford Nanopore Technologies (ONT) long-read sequencing to resolve L1 methylation genome-wide and at individual L1 loci, revealing a distinctive "smile" pattern in methylation levels across the L1 promoter region. Using Pacific Biosciences (PacBio) SMRT sequencing of L1 5' RACE products, we then examine DNA methylation dynamics at the mouse L1 promoter in parallel with transcription start site (TSS) distribution at locus-specific resolution. Together, our results offer a novel perspective on the interplay between epigenetic repression, L1 evolution, and genome stability.
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Affiliation(s)
- Patricia Gerdes
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia
| | - Dorothy Chan
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia
| | - Mischa Lundberg
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, Queensland 4102, Australia
- Translational Bioinformatics, Commonwealth Scientific and Industrial Research Organisation, Sydney, New South Wales 2113, Australia
| | - Francisco J Sanchez-Luque
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia
- GENYO. Centre for Genomics and Oncological Research (Pfizer-University of Granada-Andalusian Regional Government), PTS Granada, 18016, Spain
- MRC Human Genetics Unit, Institute of Genetics and Cancer (IGC), University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom
| | - Gabriela O Bodea
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Adam D Ewing
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia
| | - Geoffrey J Faulkner
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia;
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Sandra R Richardson
- Mater Research Institute - University of Queensland, TRI Building, Woolloongabba, Queensland 4102, Australia;
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15
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Bergin CJ, Mendes da Silva A, Benoit YD. Where to Draw the LINE-Are Retrotransposable Elements Here to Stay? Cancers (Basel) 2023; 15:4119. [PMID: 37627147 PMCID: PMC10452504 DOI: 10.3390/cancers15164119] [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: 07/19/2023] [Revised: 08/13/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
The frequency of somatic retrotranspositions of Long Interspersed Nuclear Elements 1 (LINE1) over a lifetime in healthy colonic epithelium and colorectal tumors has recently been reported. Indicative of a cell type-specific effect, LINE1 sequences in colonic epithelium showed lower levels of DNA methylation compared to other cell types examined in the study. Consistent with a role for DNA methylation in transposon silencing, the decreases in DNA methylation observed at LINE1 elements in colonic epithelium were accompanied by increases in LINE1 mRNA levels. In human primary colorectal tumors, LINE1 retrotransposition frequency was tenfold higher than in normal colonic tissues, with insertions potentially altering genomic stability and cellular functions. Here, we discuss the discoveries made by Nam and colleagues, emphasizing the intestinal-specific methylation signature regulating the LINE1 lifecycle and how this new information could shape future drug discovery endeavors against colorectal cancer.
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Affiliation(s)
- Christopher J. Bergin
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; (C.J.B.); (A.M.d.S.)
| | - Amanda Mendes da Silva
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; (C.J.B.); (A.M.d.S.)
| | - Yannick D. Benoit
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; (C.J.B.); (A.M.d.S.)
- School of Pharmaceutical Sciences, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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Sun S, Hong J, You E, Tsanov KM, Chacon-Barahona J, Gioacchino AD, Hoyos D, Li H, Jiang H, Ly H, Marhon S, Murali R, Chanda P, Karacay A, Vabret N, De Carvalho DD, LaCava J, Lowe SW, Ting DT, Iacobuzio-Donahue CA, Solovyov A, Greenbaum BD. Cancer cells co-evolve with retrotransposons to mitigate viral mimicry. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.19.541456. [PMID: 37292765 PMCID: PMC10245669 DOI: 10.1101/2023.05.19.541456] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Overexpression of repetitive elements is an emerging hallmark of human cancers 1 . Diverse repeats can mimic viruses by replicating within the cancer genome through retrotransposition, or presenting pathogen-associated molecular patterns (PAMPs) to the pattern recognition receptors (PRRs) of the innate immune system 2-5 . Yet, how specific repeats affect tumor evolution and shape the tumor immune microenvironment (TME) in a pro- or anti-tumorigenic manner remains poorly defined. Here, we integrate whole genome and total transcriptome data from a unique autopsy cohort of multiregional samples collected in pancreatic ductal adenocarcinoma (PDAC) patients, into a comprehensive evolutionary analysis. We find that more recently evolved S hort I nterspersed N uclear E lements (SINE), a family of retrotransposable repeats, are more likely to form immunostimulatory double-strand RNAs (dsRNAs). Consequently, younger SINEs are strongly co-regulated with RIG-I like receptor associated type-I interferon genes but anti-correlated with pro-tumorigenic macrophage infiltration. We discover that immunostimulatory SINE expression in tumors is regulated by either L ong I nterspersed N uclear E lements 1 (LINE1/L1) mobility or ADAR1 activity in a TP53 mutation dependent manner. Moreover, L1 retrotransposition activity tracks with tumor evolution and is associated with TP53 mutation status. Altogether, our results suggest pancreatic tumors actively evolve to modulate immunogenic SINE stress and induce pro-tumorigenic inflammation. Our integrative, evolutionary analysis therefore illustrates, for the first time, how dark matter genomic repeats enable tumors to co-evolve with the TME by actively regulating viral mimicry to their selective advantage.
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