1
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Pandkar MR, Shukla S. Epigenetics and alternative splicing in cancer: old enemies, new perspectives. Biochem J 2024; 481:1497-1518. [PMID: 39422322 DOI: 10.1042/bcj20240221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 09/30/2024] [Accepted: 10/07/2024] [Indexed: 10/19/2024]
Abstract
In recent years, significant strides in both conceptual understanding and technological capabilities have bolstered our comprehension of the factors underpinning cancer initiation and progression. While substantial insights have unraveled the molecular mechanisms driving carcinogenesis, there has been an overshadowing of the critical contribution made by epigenetic pathways, which works in concert with genetics. Mounting evidence demonstrates cancer as a complex interplay between genetics and epigenetics. Notably, epigenetic elements play a pivotal role in governing alternative pre-mRNA splicing, a primary contributor to protein diversity. In this review, we have provided detailed insights into the bidirectional communication between epigenetic modifiers and alternative splicing, providing examples of specific genes and isoforms affected. Notably, succinct discussion on targeting epigenetic regulators and the potential of the emerging field of epigenome editing to modulate splicing patterns is also presented. In summary, this review offers valuable insights into the intricate interplay between epigenetics and alternative splicing in cancer, paving the way for novel approaches to understanding and targeting this critical process.
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Affiliation(s)
- Madhura R Pandkar
- Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, Madhya Pradesh 462066, India
| | - Sanjeev Shukla
- Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, Madhya Pradesh 462066, India
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2
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Yu X, Zhang H, Zhang H, Hou C, Wang X, Gu P, Han Y, Yang Z, Zou W. The role of epigenetic methylations in thyroid Cancer. World J Surg Oncol 2024; 22:281. [PMID: 39456011 PMCID: PMC11515417 DOI: 10.1186/s12957-024-03568-2] [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: 04/26/2024] [Accepted: 10/19/2024] [Indexed: 10/28/2024] Open
Abstract
Thyroid cancer (TC) represents one of the most prevalent endocrine malignancies, with a rising incidence worldwide. Epigenetic alterations, which modify gene expression without altering the underlying DNA sequence, have garnered significant attention in recent years. Increasing evidence underscores the pivotal role of epigenetic modifications, including DNA methylation, RNA methylation, and histone methylation, in the pathogenesis of TC. This review provides a comprehensive overview of these reversible and environmentally influenced epigenetic modifications, highlighting their molecular mechanisms and functional roles in TC. Additionally, the clinical implications, challenges associated with studying these epigenetic modifications, and potential future research directions are explored.
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Affiliation(s)
- Xiaojie Yu
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China
| | - Hao Zhang
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China
| | - Haojie Zhang
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China
| | - Changran Hou
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China
| | - Xiaohong Wang
- Department of Breast Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China
| | - Pengfei Gu
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China
| | - Yong Han
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China.
| | - Zhenlin Yang
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China.
| | - Weiwei Zou
- Department of Thyroid Surgery, Binzhou Medical University Hospital, Binzhou, Shandong, 256603, P.R. China.
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3
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Maul-Newby HM, Halene S. Splicing the Difference: Harnessing the Complexity of the Transcriptome in Hematopoiesis. Exp Hematol 2024; 140:104655. [PMID: 39393608 DOI: 10.1016/j.exphem.2024.104655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2024] [Revised: 09/30/2024] [Accepted: 10/02/2024] [Indexed: 10/13/2024]
Abstract
Alternative splicing has long been recognized as a powerful tool to expand the diversity of the transcriptome and the proteome. The study of hematopoiesis, from hematopoietic stem cell maintenance and differentiation into committed progenitors to maturation into functional blood cells, has led the field of stem cell research and cellular differentiation for decades. The importance of aberrant splicing due to mutations in cis has been exemplified in thalassemias, resulting from aberrant expression of β-globin. The simultaneous development of increasingly sophisticated technologies, in particular the combination of multicolor flow cytometric cell sorting with bulk and single-cell sequencing, has provided sophisticated insights into the complex regulation of the blood system. The recognition that mutations in key splicing factors drive myeloid malignancies, in particular myelodysplastic syndromes, has galvanized research into alternative splicing in hematopoiesis and its diseases. In this review, we will update the audience on the exciting novel technologies, highlight alternative splicing events and their regulators with essential functions in hematopoiesis, and provide a high-level overview how splicing factor mutations contribute to hematologic malignancies.
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Affiliation(s)
- Hannah M Maul-Newby
- Section of Hematology, Department of Internal Medicine, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, Connecticut
| | - Stephanie Halene
- Section of Hematology, Department of Internal Medicine, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, Connecticut.
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4
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Li A, Wang R, Zhao Y, Zhao P, Yang J. Crosstalk between Epigenetics and Metabolic Reprogramming in Metabolic Dysfunction-Associated Steatotic Liver Disease-Induced Hepatocellular Carcinoma: A New Sight. Metabolites 2024; 14:325. [PMID: 38921460 PMCID: PMC11205353 DOI: 10.3390/metabo14060325] [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: 04/30/2024] [Revised: 06/01/2024] [Accepted: 06/05/2024] [Indexed: 06/27/2024] Open
Abstract
Epigenetic and metabolic reprogramming alterations are two important features of tumors, and their reversible, spatial, and temporal regulation is a distinctive hallmark of carcinogenesis. Epigenetics, which focuses on gene regulatory mechanisms beyond the DNA sequence, is a new entry point for tumor therapy. Moreover, metabolic reprogramming drives hepatocellular carcinoma (HCC) initiation and progression, highlighting the significance of metabolism in this disease. Exploring the inter-regulatory relationship between tumor metabolic reprogramming and epigenetic modification has become one of the hot directions in current tumor metabolism research. As viral etiologies have given way to metabolic dysfunction-associated steatotic liver disease (MASLD)-induced HCC, it is urgent that complex molecular pathways linking them and hepatocarcinogenesis be explored. However, how aberrant crosstalk between epigenetic modifications and metabolic reprogramming affects MASLD-induced HCC lacks comprehensive understanding. A better understanding of their linkages is necessary and urgent to improve HCC treatment strategies. For this reason, this review examines the interwoven landscape of molecular carcinogenesis in the context of MASLD-induced HCC, focusing on mechanisms regulating aberrant epigenetic alterations and metabolic reprogramming in the development of MASLD-induced HCC and interactions between them while also updating the current advances in metabolism and epigenetic modification-based therapeutic drugs in HCC.
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Affiliation(s)
- Anqi Li
- College of Basic Medical Science, Heilongjiang University of Chinese Medicine, Harbin 150040, China; (A.L.); (Y.Z.); (P.Z.)
| | - Rui Wang
- College of Pharmacy, Heilongjiang University of Chinese Medicine, Harbin 150040, China;
- Key Laboratory of Basic and Application Research of Beiyao, Heilongjiang University of Chinese Medicine, Ministry of Education, Harbin 150040, China
| | - Yuqiang Zhao
- College of Basic Medical Science, Heilongjiang University of Chinese Medicine, Harbin 150040, China; (A.L.); (Y.Z.); (P.Z.)
| | - Peiran Zhao
- College of Basic Medical Science, Heilongjiang University of Chinese Medicine, Harbin 150040, China; (A.L.); (Y.Z.); (P.Z.)
| | - Jing Yang
- College of Basic Medical Science, Heilongjiang University of Chinese Medicine, Harbin 150040, China; (A.L.); (Y.Z.); (P.Z.)
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5
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Gimeno-Valiente F, López-Rodas G, Castillo J, Franco L. The Many Roads from Alternative Splicing to Cancer: Molecular Mechanisms Involving Driver Genes. Cancers (Basel) 2024; 16:2123. [PMID: 38893242 PMCID: PMC11171328 DOI: 10.3390/cancers16112123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 05/29/2024] [Accepted: 05/31/2024] [Indexed: 06/21/2024] Open
Abstract
Cancer driver genes are either oncogenes or tumour suppressor genes that are classically activated or inactivated, respectively, by driver mutations. Alternative splicing-which produces various mature mRNAs and, eventually, protein variants from a single gene-may also result in driving neoplastic transformation because of the different and often opposed functions of the variants of driver genes. The present review analyses the different alternative splicing events that result in driving neoplastic transformation, with an emphasis on their molecular mechanisms. To do this, we collected a list of 568 gene drivers of cancer and revised the literature to select those involved in the alternative splicing of other genes as well as those in which its pre-mRNA is subject to alternative splicing, with the result, in both cases, of producing an oncogenic isoform. Thirty-one genes fall into the first category, which includes splicing factors and components of the spliceosome and splicing regulators. In the second category, namely that comprising driver genes in which alternative splicing produces the oncogenic isoform, 168 genes were found. Then, we grouped them according to the molecular mechanisms responsible for alternative splicing yielding oncogenic isoforms, namely, mutations in cis splicing-determining elements, other causes involving non-mutated cis elements, changes in splicing factors, and epigenetic and chromatin-related changes. The data given in the present review substantiate the idea that aberrant splicing may regulate the activation of proto-oncogenes or inactivation of tumour suppressor genes and details on the mechanisms involved are given for more than 40 driver genes.
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Affiliation(s)
- Francisco Gimeno-Valiente
- Cancer Evolution and Genome Instability Laboratory, University College London Cancer Institute, London WC1E 6DD, UK;
| | - Gerardo López-Rodas
- Department of Oncology, Institute of Health Research INCLIVA, 46010 Valencia, Spain; (G.L.-R.); (J.C.)
- Department of Biochemistry and Molecular Biology, Universitat de València, 46010 Valencia, Spain
| | - Josefa Castillo
- Department of Oncology, Institute of Health Research INCLIVA, 46010 Valencia, Spain; (G.L.-R.); (J.C.)
- Department of Biochemistry and Molecular Biology, Universitat de València, 46010 Valencia, Spain
- Centro de Investigación Biomédica en Red en Cáncer (CIBERONC), 28029 Madrid, Spain
| | - Luis Franco
- Department of Oncology, Institute of Health Research INCLIVA, 46010 Valencia, Spain; (G.L.-R.); (J.C.)
- Department of Biochemistry and Molecular Biology, Universitat de València, 46010 Valencia, Spain
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6
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Miano M, Bertola N, Grossi A, Dell’Orso G, Regis S, Rusmini M, Uva P, Vozzi D, Fioredda F, Palmisani E, Lupia M, Lanciotti M, Grilli F, Corsolini F, Arcuri L, Giarratana MC, Ceccherini I, Dufour C, Cappelli E, Ravera S. Impaired Mitochondrial Function and Marrow Failure in Patients Carrying a Variant of the SRSF4 Gene. Int J Mol Sci 2024; 25:2083. [PMID: 38396760 PMCID: PMC10888539 DOI: 10.3390/ijms25042083] [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: 12/12/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
Serine/arginine-rich splicing factors (SRSFs) are a family of proteins involved in RNA metabolism, including pre-mRNA constitutive and alternative splicing. The role of SRSF proteins in regulating mitochondrial activity has already been shown for SRSF6, but SRSF4 altered expression has never been reported as a cause of bone marrow failure. An 8-year-old patient admitted to the hematology unit because of leukopenia, lymphopenia, and neutropenia showed a missense variant of unknown significance of the SRSF4 gene (p.R235W) found via whole genome sequencing analysis and inherited from the mother who suffered from mild leuko-neutropenia. Both patients showed lower SRSF4 protein expression and altered mitochondrial function and energetic metabolism in primary lymphocytes and Epstein-Barr-virus (EBV)-immortalized lymphoblasts compared to healthy donor (HD) cells, which appeared associated with low mTOR phosphorylation and an imbalance in the proteins regulating mitochondrial biogenesis (i.e., CLUH) and dynamics (i.e., DRP1 and OPA1). Transfection with the wtSRSF4 gene restored mitochondrial function. In conclusion, this study shows that the described variant of the SRSF4 gene is pathogenetic and causes reduced SRSF4 protein expression, which leads to mitochondrial dysfunction. Since mitochondrial function is crucial for hematopoietic stem cell maintenance and some genetic bone marrow failure syndromes display mitochondrial defects, the SRSF4 mutation could have substantially contributed to the clinical phenotype of our patient.
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Affiliation(s)
- Maurizio Miano
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Nadia Bertola
- Molecular Pathology Unit, IRCCS Ospedale Policlinico San Martino, 16132 Genoa, Italy;
| | - Alice Grossi
- Laboratory of Genetics and Genomics of Rare Diseases, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (A.G.); (M.R.); (I.C.)
| | - Gianluca Dell’Orso
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Stefano Regis
- Laboratory of Clinical and Experimental Immunology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy;
| | - Marta Rusmini
- Laboratory of Genetics and Genomics of Rare Diseases, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (A.G.); (M.R.); (I.C.)
| | - Paolo Uva
- Clinical Bioinformatics Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy;
| | - Diego Vozzi
- Genomics Facility, Istituto Italiano di Tecnologia (IIT), 16163 Genoa, Italy;
| | - Francesca Fioredda
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Elena Palmisani
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Michela Lupia
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Marina Lanciotti
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Federica Grilli
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Fabio Corsolini
- Laboratory for the Study of Inborn Errors of Metabolism (LABSIEM), Pediatric Clinic and Endocrinology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy;
| | - Luca Arcuri
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Maria Carla Giarratana
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Isabella Ceccherini
- Laboratory of Genetics and Genomics of Rare Diseases, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (A.G.); (M.R.); (I.C.)
| | - Carlo Dufour
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Enrico Cappelli
- Haematology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy; (M.M.); (G.D.); (F.F.); (E.P.); (M.L.); (M.L.); (F.G.); (L.A.); (M.C.G.); (C.D.)
| | - Silvia Ravera
- Department of Experimental Medicine, University of Genoa, 16132 Genoa, Italy;
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Xu K, Wu T, Xia P, Chen X, Yuan Y. Alternative splicing: a bridge connecting NAFLD and HCC. Trends Mol Med 2023; 29:859-872. [PMID: 37487782 DOI: 10.1016/j.molmed.2023.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/26/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is becoming the most important risk factor for hepatocellular carcinoma (HCC). Understanding the progression of benign diseases to HCC is crucial for early prevention and reversal of malignant transformation. Alternative splicing (AS) of RNA plays a role in the pathogenicity, initiation, and transformation of liver disease. We summarize the changes or mutations in the activity of splicing factors in NAFLD and HCC, as well as the impact of AS mediated by epigenetic modifications such as DNA methylation, RNA methylation, histone modification, and protein phosphorylation on liver cell fate. We also summarize therapeutic methods and drugs that are helpful for treating NAFLD, HCC, and the early stages of NAFLD progression to HCC.
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Affiliation(s)
- Kequan Xu
- Department of Hepatobiliary and Pancreatic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, PR China; Clinical Medicine Research Center for Minimally Invasive Procedure of Hepatobiliary and Pancreatic Diseases of Hubei Province, Hubei, PR China
| | - Tiangen Wu
- Department of Hepatobiliary and Pancreatic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, PR China; Clinical Medicine Research Center for Minimally Invasive Procedure of Hepatobiliary and Pancreatic Diseases of Hubei Province, Hubei, PR China
| | - Peng Xia
- Department of Hepatobiliary and Pancreatic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, PR China; Clinical Medicine Research Center for Minimally Invasive Procedure of Hepatobiliary and Pancreatic Diseases of Hubei Province, Hubei, PR China
| | - Xi Chen
- Department of Hepatobiliary and Pancreatic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, PR China; Clinical Medicine Research Center for Minimally Invasive Procedure of Hepatobiliary and Pancreatic Diseases of Hubei Province, Hubei, PR China.
| | - Yufeng Yuan
- Department of Hepatobiliary and Pancreatic Surgery, Zhongnan Hospital of Wuhan University, Wuhan, 430071, PR China; Clinical Medicine Research Center for Minimally Invasive Procedure of Hepatobiliary and Pancreatic Diseases of Hubei Province, Hubei, PR China; TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan 430071, PR China.
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8
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Manabile MA, Hull R, Khanyile R, Molefi T, Damane BP, Mongan NP, Bates DO, Dlamini Z. Alternative Splicing Events and Their Clinical Significance in Colorectal Cancer: Targeted Therapeutic Opportunities. Cancers (Basel) 2023; 15:3999. [PMID: 37568815 PMCID: PMC10417810 DOI: 10.3390/cancers15153999] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/28/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2023] Open
Abstract
Colorectal cancer (CRC) ranks as one of the top causes of cancer mortality worldwide and its incidence is on the rise, particularly in low-middle-income countries (LMICs). There are several factors that contribute to the development and progression of CRC. Alternative splicing (AS) was found to be one of the molecular mechanisms underlying the development and progression of CRC. With the advent of genome/transcriptome sequencing and large patient databases, the broad role of aberrant AS in cancer development and progression has become clear. AS affects cancer initiation, proliferation, invasion, and migration. These splicing changes activate oncogenes or deactivate tumor suppressor genes by producing altered amounts of normally functional or new proteins with different, even opposing, functions. Thus, identifying and characterizing CRC-specific alternative splicing events and variants might help in designing new therapeutic splicing disrupter drugs. CRC-specific splicing events can be used as diagnostic and prognostic biomarkers. In this review, alternatively spliced events and their role in CRC development will be discussed. The paper also reviews recent research on alternatively spliced events that might be exploited as prognostic, diagnostic, and targeted therapeutic indicators. Of particular interest is the targeting of protein arginine methyltransferase (PMRT) isoforms for the development of new treatments and diagnostic tools. The potential challenges and limitations in translating these discoveries into clinical practice will also be addressed.
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Affiliation(s)
- Mosebo Armstrong Manabile
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Pretoria 0028, South Africa; (M.A.M.); (R.H.); (R.K.); (T.M.); (D.O.B.)
- Department of Medical Oncology, Faculty of Health Sciences, Steve Biko Academic Hospital, University of Pretoria, Pretoria 0028, South Africa
| | - Rodney Hull
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Pretoria 0028, South Africa; (M.A.M.); (R.H.); (R.K.); (T.M.); (D.O.B.)
| | - Richard Khanyile
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Pretoria 0028, South Africa; (M.A.M.); (R.H.); (R.K.); (T.M.); (D.O.B.)
- Department of Medical Oncology, Faculty of Health Sciences, Steve Biko Academic Hospital, University of Pretoria, Pretoria 0028, South Africa
| | - Thulo Molefi
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Pretoria 0028, South Africa; (M.A.M.); (R.H.); (R.K.); (T.M.); (D.O.B.)
- Department of Medical Oncology, Faculty of Health Sciences, Steve Biko Academic Hospital, University of Pretoria, Pretoria 0028, South Africa
| | - Botle Precious Damane
- Department of Surgery, Steve Biko Academic Hospital, University of Pretoria, Pretoria 0028, South Africa;
| | - Nigel Patrick Mongan
- School of Veterinary Medicine and Science, University of Nottingham, Nottingham NG7 2QL, UK;
| | - David Owen Bates
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Pretoria 0028, South Africa; (M.A.M.); (R.H.); (R.K.); (T.M.); (D.O.B.)
- Centre for Cancer Sciences, Division of Cancer and Stem Cells, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, UK
| | - Zodwa Dlamini
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Pretoria 0028, South Africa; (M.A.M.); (R.H.); (R.K.); (T.M.); (D.O.B.)
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9
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Segal D, Dostie J. The Talented LncRNAs: Meshing into Transcriptional Regulatory Networks in Cancer. Cancers (Basel) 2023; 15:3433. [PMID: 37444543 DOI: 10.3390/cancers15133433] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 07/15/2023] Open
Abstract
As a group of diseases characterized by uncontrollable cell growth, cancer is highly multifaceted in how it overrides checkpoints controlling proliferation. Amongst the regulators of these checkpoints, long non-coding RNAs (lncRNAs) can have key roles in why natural biological processes go haywire. LncRNAs represent a large class of regulatory transcripts that can localize anywhere in cells. They were found to affect gene expression on many levels from transcription to mRNA translation and even protein stability. LncRNA participation in such control mechanisms can depend on cell context, with given transcripts sometimes acting as oncogenes or tumor suppressors. Importantly, the tissue-specificity and low expression levels of lncRNAs make them attractive therapeutic targets or biomarkers. Here, we review the various cellular processes affected by lncRNAs and outline molecular strategies they use to control gene expression, particularly in cancer and in relation to transcription factors.
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Affiliation(s)
- Dana Segal
- Department of Biochemistry, McGill University, Montréal, QC H3G 1Y6, Canada
- Rosalind and Morris Goodman Cancer Institute, McGill University, Montréal, QC H3A 1A3, Canada
| | - Josée Dostie
- Department of Biochemistry, McGill University, Montréal, QC H3G 1Y6, Canada
- Rosalind and Morris Goodman Cancer Institute, McGill University, Montréal, QC H3A 1A3, Canada
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10
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Zappe K, Kopic A, Scheichel A, Schier AK, Schmidt LE, Borutzki Y, Miedl H, Schreiber M, Mendrina T, Pirker C, Pfeiler G, Hacker S, Haslik W, Pils D, Bileck A, Gerner C, Meier-Menches S, Heffeter P, Cichna-Markl M. Aberrant DNA Methylation, Expression, and Occurrence of Transcript Variants of the ABC Transporter ABCA7 in Breast Cancer. Cells 2023; 12:1462. [PMID: 37296582 PMCID: PMC10252461 DOI: 10.3390/cells12111462] [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: 02/28/2023] [Revised: 05/09/2023] [Accepted: 05/16/2023] [Indexed: 06/12/2023] Open
Abstract
The ABC transporter ABCA7 has been found to be aberrantly expressed in a variety of cancer types, including breast cancer. We searched for specific epigenetic and genetic alterations and alternative splicing variants of ABCA7 in breast cancer and investigated whether these alterations are associated with ABCA7 expression. By analyzing tumor tissues from breast cancer patients, we found CpGs at the exon 5-intron 5 boundary aberrantly methylated in a molecular subtype-specific manner. The detection of altered DNA methylation in tumor-adjacent tissues suggests epigenetic field cancerization. In breast cancer cell lines, DNA methylation levels of CpGs in promoter-exon 1, intron 1, and at the exon 5-intron 5 boundary were not correlated with ABCA7 mRNA levels. By qPCR involving intron-specific and intron-flanking primers, we identified intron-containing ABCA7 mRNA transcripts. The occurrence of intron-containing transcripts was neither molecular subtype-specific nor directly correlated with DNA methylation at the respective exon-intron boundaries. Treatment of breast cancer cell lines MCF-7, BT-474, SK-BR3, and MDA-MB-231 with doxorubicin or paclitaxel for 72 h resulted in altered ABCA7 intron levels. Shotgun proteomics revealed that an increase in intron-containing transcripts was associated with significant dysregulation of splicing factors linked to alternative splicing.
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Affiliation(s)
- Katja Zappe
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Antonio Kopic
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Alexandra Scheichel
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Ann-Katrin Schier
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Lukas Emanuel Schmidt
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Yasmin Borutzki
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Heidi Miedl
- Department of Obstetrics and Gynecology and Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Martin Schreiber
- Department of Obstetrics and Gynecology and Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Theresa Mendrina
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Christine Pirker
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Georg Pfeiler
- Division of Gynecology and Gynecological Oncology, Department of Obstetrics and Gynecology, Medical University of Vienna, 1090 Vienna, Austria
| | - Stefan Hacker
- Department of Plastic and Reconstructive Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Werner Haslik
- Department of Plastic and Reconstructive Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Dietmar Pils
- Division of Visceral Surgery, Department of General Surgery and Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
- Joint Metabolome Facility, University of Vienna and Medical University of Vienna, 1090 Vienna, Austria
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
- Joint Metabolome Facility, University of Vienna and Medical University of Vienna, 1090 Vienna, Austria
| | - Samuel Meier-Menches
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
- Joint Metabolome Facility, University of Vienna and Medical University of Vienna, 1090 Vienna, Austria
| | - Petra Heffeter
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Margit Cichna-Markl
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
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11
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Oreper D, Klaeger S, Jhunjhunwala S, Delamarre L. The peptide woods are lovely, dark and deep: Hunting for novel cancer antigens. Semin Immunol 2023; 67:101758. [PMID: 37027981 DOI: 10.1016/j.smim.2023.101758] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/22/2023] [Accepted: 03/22/2023] [Indexed: 04/08/2023]
Abstract
Harnessing the patient's immune system to control a tumor is a proven avenue for cancer therapy. T cell therapies as well as therapeutic vaccines, which target specific antigens of interest, are being explored as treatments in conjunction with immune checkpoint blockade. For these therapies, selecting the best suited antigens is crucial. Most of the focus has thus far been on neoantigens that arise from tumor-specific somatic mutations. Although there is clear evidence that T-cell responses against mutated neoantigens are protective, the large majority of these mutations are not immunogenic. In addition, most somatic mutations are unique to each individual patient and their targeting requires the development of individualized approaches. Therefore, novel antigen types are needed to broaden the scope of such treatments. We review high throughput approaches for discovering novel tumor antigens and some of the key challenges associated with their detection, and discuss considerations when selecting tumor antigens to target in the clinic.
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Affiliation(s)
- Daniel Oreper
- Genentech, 1 DNA way, South San Francisco, 94080 CA, USA.
| | - Susan Klaeger
- Genentech, 1 DNA way, South San Francisco, 94080 CA, USA.
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12
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Jiang T, Zhu J, Jiang S, Chen Z, Xu P, Gong R, Zhong C, Cheng Y, Sun X, Yi W, Yang J, Zhou W, Cheng Y. Targeting lncRNA DDIT4-AS1 Sensitizes Triple Negative Breast Cancer to Chemotherapy via Suppressing of Autophagy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023:e2207257. [PMID: 37096846 DOI: 10.1002/advs.202207257] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 04/06/2023] [Indexed: 05/03/2023]
Abstract
In this study, it is found that the lncRNA, DNA damage inducible transcript 4 antisense RNA1 (DDIT4-AS1), is highly expressed in triple-negative breast cancer (TNBC) cell lines and tissues due to H3K27 acetylation in the promoter region, and promotes the proliferation, migration, and invasion of TNBC cells via activating autophagy. Mechanistically, it is shown that DDIT4-AS1 induces autophagy by stabilizing DDIT4 mRNA via recruiting the RNA binding protein AUF1 and promoting the interaction between DDIT4 mRNA and AUF1, thereby inhibiting mTOR signaling pathway. Furthermore, silencing of DDIT4-AS1 enhances the sensitivity of TNBC cells to chemotherapeutic agents such as paclitaxel both in vitro and in vivo. Using a self-activatable siRNA/drug core-shell nanoparticle system, which effectively deliver both DDIT4-AS1 siRNA and paclitaxel to the tumor-bearing mice, a significantly enhanced antitumor activity is achieved. Importantly, the codelivery nanoparticles exert a stronger antitumor effect on breast cancer patient-derived organoids. These findings indicate that lncRNA DDIT4-AS1-mediated activation of autophagy promotes progression and chemoresistance of TNBC, and targeting of DDIT4-AS1 may be exploited as a new therapeutic approach to enhancing the efficacy of chemotherapy against TNBC.
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Affiliation(s)
- Ting Jiang
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410008, China
- Hunan Provincial Engineering Research Centre of Translational Medicine and Innovative Drug, Changsha, 410011, China
| | - Jiaojiao Zhu
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410008, China
| | - Shilong Jiang
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Zonglin Chen
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Ping Xu
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Rong Gong
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Changxin Zhong
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Yueying Cheng
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Xinyuan Sun
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410008, China
- Hunan Provincial Engineering Research Centre of Translational Medicine and Innovative Drug, Changsha, 410011, China
| | - Wenjun Yi
- Department of General Surgery, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
| | - Jinming Yang
- Department of Cancer Biology and Toxicology, Department of Pharmacology, College of Medicine and Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Wenhu Zhou
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410008, China
| | - Yan Cheng
- Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, China
- Hunan Provincial Engineering Research Centre of Translational Medicine and Innovative Drug, Changsha, 410011, China
- Key Laboratory of Diabetes Immunology (Central South University), Ministry of Education, Changsha, 410011, China
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13
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Splicing-Disrupting Mutations in Inherited Predisposition to Solid Pediatric Cancer. Cancers (Basel) 2022; 14:cancers14235967. [PMID: 36497448 PMCID: PMC9739414 DOI: 10.3390/cancers14235967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 12/09/2022] Open
Abstract
The prevalence of hereditary cancer in children was estimated to be very low until recent studies suggested that at least 10% of pediatric cancer patients carry a germline mutation in a cancer predisposition gene. A significant proportion of pathogenic variants associated with an increased risk of hereditary cancer are variants affecting splicing. RNA splicing is an essential process involved in different cellular processes such as proliferation, survival, and differentiation, and alterations in this pathway have been implicated in many human cancers. Hereditary cancer genes are highly susceptible to splicing mutations, and among them there are several genes that may contribute to pediatric solid tumors when mutated in the germline. In this review, we have focused on the analysis of germline splicing-disrupting mutations found in pediatric solid tumors, as the discovery of pathogenic splice variants in pediatric cancer is a growing field for the development of personalized therapies. Therapies developed to correct aberrant splicing in cancer are also discussed as well as the options to improve the diagnostic yield based on the increase in the knowledge in splicing.
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14
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Curcumin: An epigenetic regulator and its application in cancer. Biomed Pharmacother 2022; 156:113956. [DOI: 10.1016/j.biopha.2022.113956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
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15
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Setlai BP, Mkhize-Kwitshana ZL, Mehrotra R, Mulaudzi TV, Dlamini Z. Microbiomes, Epigenomics, Immune Response, and Splicing Signatures Interplay: Potential Use of Combination of Regulatory Pathways as Targets for Malignant Mesothelioma. Int J Mol Sci 2022; 23:8991. [PMID: 36012262 PMCID: PMC9409175 DOI: 10.3390/ijms23168991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 07/30/2022] [Accepted: 08/03/2022] [Indexed: 11/16/2022] Open
Abstract
Malignant mesotheliomas (MM) are hard to treat malignancies with poor prognosis and high mortality rates. This cancer is highly misdiagnosed in Sub-Saharan African countries. According to literature, the incidence of MM is likely to increase particularly in low-middle-income countries (LMICs). The burden of asbestos-induced diseases was estimated to be about 231,000 per annum. Lack of awareness and implementation of regulatory frameworks to control exposure to asbestos fibers contributes to the expected increase. Exposure to asbestos fibers can lead to cancer initiation by several mechanisms. Asbestos-induced epigenetic modifications of gene expression machinery and non-coding RNAs promote cancer initiation and progression. Furthermore, microbiome-epigenetic interactions control the innate and adaptive immunity causing exacerbation of cancer progression and therapeutic resistance. This review discusses epigenetic mechanisms with more focus on miRNAs and their interaction with the microbiome. The potential use of epigenetic alterations and microbiota as specific biomarkers to aid in the early detection and/or development of therapeutic targets is explored. The advancement of combinatorial therapies to prolong overall patient survival or possible eradication of MM especially if it is detected early is discussed.
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Affiliation(s)
- Botle Precious Setlai
- Department of Surgery, Level 7, Bridge E, Steve Biko Academic Hospital, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0007, South Africa
- Department of Medical Microbiology, School of Laboratory Medicine & Medical Sciences, Medical School Campus, College of Health Sciences, University of KwaZulu-Natal-Natal, Durban 4041, South Africa
| | - Zilungile Lynette Mkhize-Kwitshana
- Department of Medical Microbiology, School of Laboratory Medicine & Medical Sciences, Medical School Campus, College of Health Sciences, University of KwaZulu-Natal-Natal, Durban 4041, South Africa
| | - Ravi Mehrotra
- India Cancer Research Consortium (ICMR-DHR), Department of Health Research, Red Cross Road, New Delhi 110001, India
| | - Thanyani Victor Mulaudzi
- Department of Surgery, Level 7, Bridge E, Steve Biko Academic Hospital, Faculty of Health Sciences, University of Pretoria, Private Bag X323, Pretoria 0007, South Africa
| | - Zodwa Dlamini
- SAMRC Precision Oncology Research Unit (PORU), DSI/NRF SARChI Chair in Precision Oncology and Cancer Prevention (POCP), Pan African Cancer Research Institute (PACRI), University of Pretoria, Hatfield 0028, South Africa
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16
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De Kesel J, Fijalkowski I, Taylor J, Ntziachristos P. Splicing dysregulation in human hematologic malignancies: beyond splicing mutations. Trends Immunol 2022; 43:674-686. [PMID: 35850914 DOI: 10.1016/j.it.2022.06.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/09/2022] [Accepted: 06/14/2022] [Indexed: 11/16/2022]
Abstract
Splicing is a fundamental process in pre-mRNA maturation. Whereas alternative splicing (AS) enriches the diversity of the proteome, its aberrant regulation can drive oncogenesis. So far, most attention has been given to spliceosome mutations (SMs) in the context of splicing dysregulation in hematologic diseases. However, in recent years, post-translational modifications (PTMs) and transcriptional alterations of splicing factors (SFs), just as epigenetic signatures, have all been shown to contribute to global splicing dysregulation as well. In addition, the contribution of aberrant splicing to the neoantigen repertoire of cancers has been recognized. With the pressing need for novel therapeutics to combat blood cancers, this article provides an overview of emerging mechanisms that contribute to aberrant splicing, as well as their clinical potential.
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Affiliation(s)
- Jonas De Kesel
- Department of Biomolecular Medicine, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent, Ghent, Belgium; Center for Medical Genetics Ghent, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - Igor Fijalkowski
- Department of Biomolecular Medicine, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent, Ghent, Belgium; Center for Medical Genetics Ghent, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - Justin Taylor
- Division of Hematology, Department of Medicine, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Panagiotis Ntziachristos
- Department of Biomolecular Medicine, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent, Ghent, Belgium; Center for Medical Genetics Ghent, Ghent University and Ghent University Hospital, Ghent, Belgium.
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17
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Imbriano C, Belluti S. Histone Marks-Dependent Effect on Alternative Splicing: New Perspectives for Targeted Splicing Modulation in Cancer? Int J Mol Sci 2022; 23:ijms23158304. [PMID: 35955433 PMCID: PMC9368390 DOI: 10.3390/ijms23158304] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/23/2022] [Accepted: 07/25/2022] [Indexed: 11/16/2022] Open
Abstract
Alternative splicing (AS) is a tightly regulated mechanism that generates the complex human proteome from a small number of genes. Cis-regulatory RNA motifs in exons and introns control AS, recruiting positive and negative trans-acting splicing regulators. At a higher level, chromatin affects splicing events. Growing evidence indicates that the popular histone code hypothesis can be extended to RNA-level processes, such as AS. In addition to nucleosome positioning, which can generate transcriptional barriers to shape the final splicing outcome, histone post-translational modifications can contribute to the detailed regulation of single exon inclusion/exclusion. A histone-based system can identify alternatively spliced chromatin stretches, affecting RNAPII elongation locally or recruiting splicing components via adaptor complexes. In tumor cells, several mechanisms trigger misregulated AS events and produce cancer-associated transcripts. On a genome-wide level, aberrant AS can be the consequence of dysfunctional epigenetic splicing code, including altered enrichment in histone post-translational modifications. This review describes the main findings related to the effect of histone modifications and variants on splicing outcome and how a dysfunctional epigenetic splicing code triggers aberrant AS in cancer. In addition, it highlights recent advances in programmable DNA-targeting technologies and their possible application for AS targeted epigenetic modulation.
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