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Prashanth S, Radha Maniswami R, Rajajeyabalachandran G, Jegatheesan SK. SETDB1, an H3K9-specific methyltransferase: An attractive epigenetic target to combat cancer. Drug Discov Today 2024; 29:103982. [PMID: 38614159 DOI: 10.1016/j.drudis.2024.103982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 03/28/2024] [Accepted: 04/08/2024] [Indexed: 04/15/2024]
Abstract
SET domain bifurcated histone lysine methyltransferase 1 (SETDB1) is an important epigenetic regulator catalyzing histone H3 lysine 9 (H3K9) methylation, specifically di-/tri-methylation. This regulation promotes gene silencing through heterochromatin formation. Aberrant SETDB1 expression, and its oncogenic role is evident in many cancers. Thus, SETDB1 is a valid target with novel therapeutic benefits. In this review, we explore the structural and biochemical features of SETDB1, its regulatory mechanisms, and its role in various cancers. We also discuss recent discoveries in small molecules targeting SETDB1 and provide suggestions for future research.
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Affiliation(s)
- Seema Prashanth
- Informatics, AI & ML, Jubilant Biosys Ltd., Bangalore, India
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2
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Huang X, Chen Y, Xiao Q, Shang X, Liu Y. Chemical inhibitors targeting histone methylation readers. Pharmacol Ther 2024; 256:108614. [PMID: 38401773 DOI: 10.1016/j.pharmthera.2024.108614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/01/2024] [Accepted: 02/15/2024] [Indexed: 02/26/2024]
Abstract
Histone methylation reader domains are protein modules that recognize specific histone methylation marks, such as methylated or unmethylated lysine or arginine residues on histones. These reader proteins play crucial roles in the epigenetic regulation of gene expression, chromatin structure, and DNA damage repair. Dysregulation of these proteins has been linked to various diseases, including cancer, neurodegenerative diseases, and developmental disorders. Therefore, targeting these proteins with chemical inhibitors has emerged as an attractive approach for therapeutic intervention, and significant progress has been made in this area. In this review, we will summarize the development of inhibitors targeting histone methylation readers, including MBT domains, chromodomains, Tudor domains, PWWP domains, PHD fingers, and WD40 repeat domains. For each domain, we will briefly discuss its identification and biological/biochemical functions, and then focus on the discovery of inhibitors tailored to target this domain, summarizing the property and potential application of most inhibitors. We will also discuss the structural basis for the potency and selectivity of these inhibitors, which will aid in further lead generation and optimization. Finally, we will also address the challenges and strategies involved in the development of these inhibitors. It should facilitate the rational design and development of novel chemical scaffolds and new targeting strategies for histone methylation reader domains with the help of this body of data.
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Affiliation(s)
- Xiaolei Huang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, PR China
| | - Yichang Chen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, PR China
| | - Qin Xiao
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, PR China
| | - Xinci Shang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, PR China
| | - Yanli Liu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, PR China.
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3
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Ma T, Xu F, Hou Y, Shu Y, Zhao Z, Zhang Y, Bai L, Feng L, Zhong L. SETDB1: Progress and prospects in cancer treatment potential and inhibitor research. Bioorg Chem 2024; 145:107219. [PMID: 38377821 DOI: 10.1016/j.bioorg.2024.107219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 02/03/2024] [Accepted: 02/14/2024] [Indexed: 02/22/2024]
Abstract
SET domain bifurcated methyltransferase 1 (SETDB1) serves as a histone lysine methyltransferase, catalyzing the di- and tri-methylation of histone H3K9. Mounting evidence indicates that the abnormal expression or activity of SETDB1, either through amplification or mutation, plays a crucial role in tumorigenesis and progression. This is particularly evident in the context of tumor immune evasion and resistance to immune checkpoint blockade therapy. Furthermore, there is a robust association between SETDB1 dysregulation and an unfavorable prognosis across various types of tumors. The oncogenic role of SETDB1 primarily arises from its methyltransferase function, which contributes to the establishment of a condensed and transcriptionally inactive heterochromatin state. This results in the inactivation of genes that typically hinder cancer development and silencing of retrotransposons that could potentially trigger an immune response. These findings underscore the substantial potential for SETDB1 as an anti-tumor therapeutic target. Nevertheless, despite significant strides in recent years in tumor biology research, challenges persist in SETDB1-targeted therapy. To better facilitate the development of anti-tumor therapy targeting SETDB1, we have conducted a comprehensive review of SETDB1 in this account. We present the structure and function of SETDB1, its role in various tumors and immune regulation, as well as the advancements made in SETDB1 antagonists. Furthermore, we discuss the challenges encountered and provide perspectives for the development of SETDB1-targeted anti-tumor therapy.
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Affiliation(s)
- Tingnan Ma
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China
| | - Feifei Xu
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China; State Key Laboratory of Southwestern Chinese Medicine Resources; Key Laboratory of Standardization of Chinese Herbal Medicines of Ministry of Education, Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, China
| | - Yingying Hou
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China
| | - Yongquan Shu
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China
| | - Zhipeng Zhao
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China
| | - Yaru Zhang
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China
| | - Lan Bai
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China.
| | - Lu Feng
- Department of Emergency, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 610041, China.
| | - Lei Zhong
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China.
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Gold S, Shilatifard A. Therapeutic targeting of BET bromodomain and other epigenetic acetylrecognition domain-containing factors. Curr Opin Genet Dev 2024; 86:102181. [PMID: 38564841 DOI: 10.1016/j.gde.2024.102181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/03/2024] [Accepted: 03/04/2024] [Indexed: 04/04/2024]
Abstract
Development of cancer therapies targeting chromatin modifiers and transcriptional regulatory factors is rapidly expanding to include new targets and novel targeting strategies. At the same time, basic molecular research continues to refine our understanding of the epigenetic mechanisms regulating transcription, gene expression, and oncogenesis. This mini-review focuses on cancer therapies targeting the chromatin-associated factors that recognize histone lysine acetylation. Recently reported safety and efficacy are discussed for inhibitors targeting the bromodomains of bromodomain and extraterminal domain (BET) family proteins. In light of recent results indicating that the transcriptional regulator BRD4-PTEFb can function independently of BRD4's bromodomains, the clinical trial performance of these BET inhibitors is placed in a broader context of existing and potential strategies for targeting BRD4-PTEFb. Recently developed therapies targeting bromodomain-containing factors within the SWI/SNF (BAF) family of chromatin remodeling complexes are discussed, as is the potential for targeting the bromodomain-containing transcription factor TAF1 and the YEATS acetylrecognition domain-containing factor GAS41. Recent findings regarding the selectivity and combinatorial specificity of acetylrecognition are highlighted. In conclusion, the potential for further development is discussed with a focus on proximity-based therapies targeting this class of epigenetic factors.
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Affiliation(s)
- Sarah Gold
- Department of Biochemistry and Molecular Genetics, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA. https://twitter.com/@rwx_life
| | - Ali Shilatifard
- Department of Biochemistry and Molecular Genetics, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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Luo F, Zhang M, Sun B, Xu C, Yang Y, Zhang Y, Li S, Chen G, Chen C, Li Y, Feng H. LINC00115 promotes chemoresistant breast cancer stem-like cell stemness and metastasis through SETDB1/PLK3/HIF1α signaling. Mol Cancer 2024; 23:60. [PMID: 38520019 PMCID: PMC10958889 DOI: 10.1186/s12943-024-01975-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 02/28/2024] [Indexed: 03/25/2024] Open
Abstract
BACKGROUND Cancer stem-like cell is a key barrier for therapeutic resistance and metastasis in various cancers, including breast cancer, yet the underlying mechanisms are still elusive. Through a genome-wide lncRNA expression profiling, we identified that LINC00115 is robustly upregulated in chemoresistant breast cancer stem-like cells (BCSCs). METHODS LncRNA microarray assay was performed to document abundance changes of lncRNAs in paclitaxel (PTX)-resistant MDA-MB-231 BCSC (ALDH+) and non-BCSC (ALDH-). RNA pull-down and RNA immunoprecipitation (RIP) assays were performed to determine the binding proteins of LINC00115. The clinical significance of the LINC00115 pathway was examined in TNBC metastatic lymph node tissues. The biological function of LINC00115 was investigated through gain- and loss-of-function studies. The molecular mechanism was explored through RNA sequencing, mass spectrometry, and the CRISPR/Cas9-knockout system. The therapeutic potential of LINC00115 was examined through xenograft animal models. RESULTS LINC00115 functions as a scaffold lncRNA to link SETDB1 and PLK3, leading to enhanced SETDB1 methylation of PLK3 at both K106 and K200 in drug-resistant BCSC. PLK3 methylation decreases PLK3 phosphorylation of HIF1α and thereby increases HIF1α stability. HIF1α, in turn, upregulates ALKBH5 to reduce m6A modification of LINC00115, resulting in attenuated degradation of YTHDF2-dependent m6A-modified RNA and enhanced LINC00115 stability. Thus, this positive feedback loop provokes BCSC phenotypes and enhances chemoresistance and metastasis in triple-negative breast cancer. SETDB1 inhibitor TTD-IN with LINC00115 ASO sensitizes PTX-resistant cell response to chemotherapy in a xenograft animal model. Correlative expression of LINC00115, methylation PLK3, SETDB1, and HIF1α are prognostic for clinical triple-negative breast cancers. CONCLUSIONS Our findings uncover LINC00115 as a critical regulator of BCSC and highlight targeting LINC00115 and SETDB1 as a potential therapeutic strategy for chemotherapeutic resistant breast cancer.
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Affiliation(s)
- Fei Luo
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Mingda Zhang
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Bowen Sun
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Chenxin Xu
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Yi Yang
- Pediatric Translational Medicine Institute, Department of Hematology & Oncology, Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, National Health Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai, 200127, China
| | - Yingwen Zhang
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Shanshan Li
- Pediatric Translational Medicine Institute, Department of Hematology & Oncology, Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, National Health Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai, 200127, China
| | - Guoyu Chen
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Ceshi Chen
- Academy of Biomedical Engineering, the Third Affiliated Hospital, Kunming Medical University, Kunming, 650500, China.
| | - Yanxin Li
- Pediatric Translational Medicine Institute, Department of Hematology & Oncology, Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, National Health Committee Key Laboratory of Pediatric Hematology & Oncology, Shanghai, 200127, China.
| | - Haizhong Feng
- State Key Laboratory of Systems Medicine for Cancer, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China.
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de Groot AP, de Haan G. How CBX proteins regulate normal and leukemic blood cells. FEBS Lett 2024. [PMID: 38426219 DOI: 10.1002/1873-3468.14839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/26/2024] [Accepted: 02/09/2024] [Indexed: 03/02/2024]
Abstract
Hematopoietic stem cell (HSC) fate decisions are dictated by epigenetic landscapes. The Polycomb Repressive Complex 1 (PRC1) represses genes that induce differentiation, thereby maintaining HSC self-renewal. Depending on which chromobox (CBX) protein (CBX2, CBX4, CBX6, CBX7, or CBX8) is part of the PRC1 complex, HSC fate decisions differ. Here, we review how this occurs. We describe how CBX proteins dictate age-related changes in HSCs and stimulate oncogenic HSC fate decisions, either as canonical PRC1 members or by alternative interactions, including non-epigenetic regulation. CBX2, CBX7, and CBX8 enhance leukemia progression. To target, reprogram, and kill leukemic cells, we suggest and describe multiple therapeutic strategies to interfere with the epigenetic functions of oncogenic CBX proteins. Future studies should clarify to what extent the non-epigenetic function of cytoplasmic CBX proteins is important for normal, aged, and leukemic blood cells.
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Affiliation(s)
- Anne P de Groot
- European Research Institute for Biology of Ageing (ERIBA), University Medical Center Groningen (UMCG), The Netherlands
- Sanquin Research, Landsteiner Laboratory, Sanquin Blood Supply, Amsterdam, The Netherlands
| | - Gerald de Haan
- European Research Institute for Biology of Ageing (ERIBA), University Medical Center Groningen (UMCG), The Netherlands
- Sanquin Research, Landsteiner Laboratory, Sanquin Blood Supply, Amsterdam, The Netherlands
- Department of Hematology, Amsterdam UMC, University of Amsterdam, The Netherlands
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Noberini R, Bonaldi T. Proteomics contributions to epigenetic drug discovery. Proteomics 2023; 23:e2200435. [PMID: 37727062 DOI: 10.1002/pmic.202200435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/21/2023]
Abstract
The combined activity of epigenetic features, which include histone post-translational modifications, DNA methylation, and nucleosome positioning, regulates gene expression independently from changes in the DNA sequence, defining how the shared genetic information of an organism is used to generate different cell phenotypes. Alterations in epigenetic processes have been linked with a multitude of diseases, including cancer, fueling interest in the discovery of drugs targeting the proteins responsible for writing, erasing, or reading histone and DNA modifications. Mass spectrometry (MS)-based proteomics has emerged as a versatile tool that can assist drug discovery pipelines from target validation, through target deconvolution, to monitoring drug efficacy in vivo. Here, we provide an overview of the contributions of MS-based proteomics to epigenetic drug discovery, describing the main approaches that can be used to support different drug discovery pipelines and highlighting how they contributed to the development and characterization of epigenetic drugs.
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Affiliation(s)
- Roberta Noberini
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Tiziana Bonaldi
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
- Department of Oncology and Hematology-Oncology, University of Milan, Milan, Italy
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Uguen M, Deng Y, Li F, Shell DJ, Norris-Drouin JL, Stashko MA, Ackloo S, Arrowsmith CH, James LI, Liu P, Pearce KH, Frye SV. SETDB1 Triple Tudor Domain Ligand, ( R, R)-59, Promotes Methylation of Akt1 in Cells. ACS Chem Biol 2023; 18:1846-1853. [PMID: 37556795 PMCID: PMC10718286 DOI: 10.1021/acschembio.3c00280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Increased expression and hyperactivation of the methyltransferase SET domain bifurcated 1 (SETDB1) are commonly observed in cancer and central nervous system disorders. However, there are currently no reported SETDB1-specific methyltransferase inhibitors in the literature, suggesting that this is a challenging target. Here, we disclose that the previously reported small-molecule ligand for SETDB1's triple tudor domain, (R,R)-59, is unexpectedly able to increase SETDB1 methyltransferase activity both in vitro and in cells. Specifically, (R,R)-59 promotes in vitro SETDB1-mediated methylation of lysine 64 of the protein kinase Akt1. Treatment with (R,R)-59 also increased Akt1 threonine 308 phosphorylation and activation, a known consequence of Akt1 methylation, resulting in stimulated cell proliferation in a dose-dependent manner. (R,R)-59 is the first SETDB1 small-molecule positive activator for the methyltransferase activity of this protein. Mechanism of action studies show that full-length SETDB1 is required for significant in vitro methylation of an Akt1-K64 peptide and that this activity is stimulated by (R,R)-59 primarily through an increase in catalytic activity rather than a change in S-adenosyl methionine binding.
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Affiliation(s)
- Mélanie Uguen
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Yu Deng
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Fengling Li
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Devan J Shell
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Jacqueline L Norris-Drouin
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Michael A Stashko
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Suzanne Ackloo
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Cheryl H Arrowsmith
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Lindsey I James
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Pengda Liu
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Kenneth H Pearce
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Stephen V Frye
- UNC Eshelman School of Pharmacy, Center for Integrative Chemical Biology and Drug Discovery, Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
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Liu R, Wu J, Guo H, Yao W, Li S, Lu Y, Jia Y, Liang X, Tang J, Zhang H. Post-translational modifications of histones: Mechanisms, biological functions, and therapeutic targets. MedComm (Beijing) 2023; 4:e292. [PMID: 37220590 PMCID: PMC10200003 DOI: 10.1002/mco2.292] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 05/25/2023] Open
Abstract
Histones are DNA-binding basic proteins found in chromosomes. After the histone translation, its amino tail undergoes various modifications, such as methylation, acetylation, phosphorylation, ubiquitination, malonylation, propionylation, butyrylation, crotonylation, and lactylation, which together constitute the "histone code." The relationship between their combination and biological function can be used as an important epigenetic marker. Methylation and demethylation of the same histone residue, acetylation and deacetylation, phosphorylation and dephosphorylation, and even methylation and acetylation between different histone residues cooperate or antagonize with each other, forming a complex network. Histone-modifying enzymes, which cause numerous histone codes, have become a hot topic in the research on cancer therapeutic targets. Therefore, a thorough understanding of the role of histone post-translational modifications (PTMs) in cell life activities is very important for preventing and treating human diseases. In this review, several most thoroughly studied and newly discovered histone PTMs are introduced. Furthermore, we focus on the histone-modifying enzymes with carcinogenic potential, their abnormal modification sites in various tumors, and multiple essential molecular regulation mechanism. Finally, we summarize the missing areas of the current research and point out the direction of future research. We hope to provide a comprehensive understanding and promote further research in this field.
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Affiliation(s)
- Ruiqi Liu
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
- Graduate DepartmentBengbu Medical College, BengbuAnhuiChina
| | - Jiajun Wu
- Graduate DepartmentBengbu Medical College, BengbuAnhuiChina
- Otolaryngology & Head and Neck CenterCancer CenterDepartment of Head and Neck SurgeryZhejiang Provincial People's HospitalAffiliated People's Hospital, Hangzhou Medical CollegeHangzhouZhejiangChina
| | - Haiwei Guo
- Otolaryngology & Head and Neck CenterCancer CenterDepartment of Head and Neck SurgeryZhejiang Provincial People's HospitalAffiliated People's Hospital, Hangzhou Medical CollegeHangzhouZhejiangChina
| | - Weiping Yao
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
- Graduate DepartmentBengbu Medical College, BengbuAnhuiChina
| | - Shuang Li
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
- Graduate DepartmentJinzhou Medical UniversityJinzhouLiaoningChina
| | - Yanwei Lu
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
| | - Yongshi Jia
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
| | - Xiaodong Liang
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
- Graduate DepartmentBengbu Medical College, BengbuAnhuiChina
| | - Jianming Tang
- Department of Radiation OncologyThe First Hospital of Lanzhou UniversityLanzhou UniversityLanzhouGansuChina
| | - Haibo Zhang
- Cancer CenterDepartment of Radiation OncologyZhejiang Provincial People's HospitalAffiliated People's HospitalHangzhou Medical CollegeHangzhouZhejiangChina
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Ortiz G, Kutateladze TG, Fujimori DG. Chemical tools targeting readers of lysine methylation. Curr Opin Chem Biol 2023; 74:102286. [PMID: 36948085 PMCID: PMC10264141 DOI: 10.1016/j.cbpa.2023.102286] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 02/01/2023] [Accepted: 02/20/2023] [Indexed: 03/22/2023]
Abstract
Reader domains that recognize methylated lysine and arginine residues on histones play a role in the recruitment, stabilization, and regulation of chromatin regulatory proteins. Targeting reader proteins with small molecule and peptidomimetic inhibitors has enabled the elucidation of the structure and function of specific domains and uncovered their role in diseases. Recent progress towards chemical probes that target readers of lysine methylation, including the Royal family and plant homeodomains (PHD), is discussed here. We highlight recently developed covalent cyclic peptide inhibitors of a plant homeodomain. Additionally, inhibitors targeting previously untargeted Tudor domains and chromodomains are discussed.
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Affiliation(s)
- Gloria Ortiz
- Department of Cellular and Molecular Pharmacology, University of California San Francisco San Francisco, CA 94158, USA
| | - Tatiana G Kutateladze
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
| | - Danica Galonic Fujimori
- Department of Cellular and Molecular Pharmacology, University of California San Francisco San Francisco, CA 94158, USA; Department of Pharmaceutical Chemistry, University of California San Francisco San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California San Francisco San Francisco, CA 94158, USA.
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Uguen M, Deng Y, Li F, Shell DJ, Norris-Drouin JL, Stashko MA, Ackloo S, Arrowsmith CH, James LI, Liu P, Pearce KH, Frye SV. SETDB1 Triple Tudor Domain Ligand, ( R,R )-59, Promotes Methylation of Akt1 in Cells. bioRxiv 2023:2023.05.10.539986. [PMID: 37214894 PMCID: PMC10197638 DOI: 10.1101/2023.05.10.539986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Increased expression and hyperactivation of the methyltransferase SETDB1 are commonly observed in cancer and central nervous system disorders. However, there are currently no reported SETDB1-specific methyltransferase inhibitors in the literature, suggesting this is a challenging target. Here, we disclose that the previously reported small-molecule ligand for SETDB1's Triple Tudor Domain, ( R,R )-59, is unexpectedly able to increase SETDB1 methyltransferase activity both in vitro and in cells. Specifically, ( R,R )-59 promotes in vitro SETDB1-mediated methylation of lysine 64 of the protein kinase Akt1. Treatment with ( R,R )-59 also increased Akt1 threonine 308 phosphorylation and activation, a known consequence of Akt1 methylation, resulting in stimulated cell proliferation in a dose-dependent manner. ( R,R )-59 is the first SETDB1 small-molecule positive activator for the methyltransferase activity of this protein. Mechanism of action studies show that full-length SETDB1 is required for significant in vitro methylation of an Akt1-K64 peptide, and that this activity is stimulated by ( R,R )-59 primarily through an increase in catalytic activity rather than a change in SAM binding. Abstract Figure
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Fisher ML, Balinth S, Mills AA. ΔNp63α in cancer: importance and therapeutic opportunities. Trends Cell Biol 2023; 33:280-292. [PMID: 36115734 PMCID: PMC10011024 DOI: 10.1016/j.tcb.2022.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/09/2022] [Accepted: 08/22/2022] [Indexed: 10/14/2022]
Abstract
Our understanding of cancer and the key pathways that drive cancer survival has expanded rapidly over the past several decades. However, there are still important challenges that continue to impair patient survival, including our inability to target cancer stem cells (CSCs), metastasis, and drug resistance. The transcription factor p63 is a p53 family member with multiple isoforms that carry out a wide array of functions. Here, we discuss the critical importance of the ΔNp63α isoform in cancer and potential therapeutic strategies to target ΔNp63α expression to impair the CSC population, as well as to prevent metastasis and drug resistance to improve patient survival.
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Affiliation(s)
- Matthew L Fisher
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Seamus Balinth
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, NY 11794, USA
| | - Alea A Mills
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
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Hu G, Shi X, Qu X, Han C, Hu A, Jia Z, Yang J, Liu H, Wu Y. Atf7ip Inhibits Osteoblast Differentiation via Negative Regulation of the Sp7 Transcription Factor. Int J Mol Sci 2023; 24. [PMID: 36901736 DOI: 10.3390/ijms24054305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 02/03/2023] [Accepted: 02/15/2023] [Indexed: 02/24/2023] Open
Abstract
Epigenetic modifications are critical for cell differentiation and growth. As a regulator of H3K9 methylation, Setdb1 is implicated in osteoblast proliferation and differentiation. The activity and nucleus localization of Setdb1 are regulated by its binding partner, Atf7ip. However, whether Atf7ip is involved in the regulation of osteoblast differentiation remains largely unclear. In the present study, we found that Atf7ip expression was upregulated during the osteogenesis of primary bone marrow stromal cells and MC3T3-E1 cells, and was induced in PTH-treated cells. The overexpression of Atf7ip impaired osteoblast differentiation in MC3T3-E1 cells regardless of PTH treatment, as measured by the expression of osteoblast differentiation markers, Alp-positive cells, Alp activity, and calcium deposition. Conversely, the depletion of Atf7ip in MC3T3-E1 cells promoted osteoblast differentiation. Compared with the control mice, animals with Atf7ip deletion in the osteoblasts (Oc-Cre;Atf7ipf/f) showed more bone formation and a significant increase in the bone trabeculae microarchitecture, as reflected by μ-CT and bone histomorphometry. Mechanistically, Atf7ip contributed to the nucleus localization of Setdb1 in MC3T3-E1, but did not affect Setdb1 expression. Atf7ip negatively regulated Sp7 expression, and through specific siRNA, Sp7 knockdown attenuated the enhancing role of Atf7ip deletion in osteoblast differentiation. Through these data, we identified Atf7ip as a novel negative regulator of osteogenesis, possibly via its epigenetic regulation of Sp7 expression, and demonstrated that Atf7ip inhibition is a potential therapeutic measure for enhancing bone formation.
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Kumar A, Emdad L, Fisher PB, Das SK. Targeting epigenetic regulation for cancer therapy using small molecule inhibitors. Adv Cancer Res 2023; 158:73-161. [PMID: 36990539 DOI: 10.1016/bs.acr.2023.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Cancer cells display pervasive changes in DNA methylation, disrupted patterns of histone posttranslational modification, chromatin composition or organization and regulatory element activities that alter normal programs of gene expression. It is becoming increasingly clear that disturbances in the epigenome are hallmarks of cancer, which are targetable and represent attractive starting points for drug creation. Remarkable progress has been made in the past decades in discovering and developing epigenetic-based small molecule inhibitors. Recently, epigenetic-targeted agents in hematologic malignancies and solid tumors have been identified and these agents are either in current clinical trials or approved for treatment. However, epigenetic drug applications face many challenges, including low selectivity, poor bioavailability, instability and acquired drug resistance. New multidisciplinary approaches are being designed to overcome these limitations, e.g., applications of machine learning, drug repurposing, high throughput virtual screening technologies, to identify selective compounds with improved stability and better bioavailability. We provide an overview of the key proteins that mediate epigenetic regulation that encompass histone and DNA modifications and discuss effector proteins that affect the organization of chromatin structure and function as well as presently available inhibitors as potential drugs. Current anticancer small-molecule inhibitors targeting epigenetic modified enzymes that have been approved by therapeutic regulatory authorities across the world are highlighted. Many of these are in different stages of clinical evaluation. We also assess emerging strategies for combinatorial approaches of epigenetic drugs with immunotherapy, standard chemotherapy or other classes of agents and advances in the design of novel epigenetic therapies.
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Zhao Z, Feng L, Peng X, Ma T, Tong R, Zhong L. Role of histone methyltransferase SETDB1 in regulation of tumourigenesis and immune response. Front Pharmacol 2022; 13:1073713. [PMID: 36582533 PMCID: PMC9793902 DOI: 10.3389/fphar.2022.1073713] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/29/2022] [Indexed: 12/15/2022] Open
Abstract
Epigenetic alterations are implicated in tumour immune evasion and immune checkpoint blockade (ICB) resistance. SET domain bifurcated histone methyltransferase 1 (SETDB1) is a histone lysine methyltransferase that catalyses histone H3K9 di- and tri-methylation on euchromatin, and growing evidence indicates that SETDB1 amplification and abnormal activation are significantly correlated with the unfavourable prognosis of multiple malignant tumours and contribute to tumourigenesis and progression, immune evasion and ICB resistance. The main underlying mechanism is H3K9me3 deposition by SETDB1 on tumour-suppressive genes, retrotransposons, and immune genes. SETDB1 targeting is a promising approach to cancer therapy, particularly immunotherapy, because of its regulatory effects on endogenous retroviruses. However, SETDB1-targeted therapy remains challenging due to potential side effects and the lack of antagonists with high selectivity and potency. Here, we review the role of SETDB1 in tumourigenesis and immune regulation and present the current challenges and future perspectives of SETDB1 targeted therapy.
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Affiliation(s)
- Zhipeng Zhao
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lu Feng
- Department of Emergency, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu, China
| | - Xuerun Peng
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Tingnan Ma
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Rongsheng Tong
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lei Zhong
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China,*Correspondence: Lei Zhong,
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Rovers E, Liu L, Schapira M. ProxyBind: a Compendium of Binding Sites for Proximity-Induced Pharmacology. Comput Struct Biotechnol J 2022; 20:6163-6171. [PMID: 36420167 PMCID: PMC9674861 DOI: 10.1016/j.csbj.2022.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/04/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
Proximity-induced pharmacology (ProxPharm) is a novel paradigm in drug discovery where a small molecule brings two proteins in close proximity to elicit a signal, generally from one protein onto another. The potential of ProxPharm compounds as a new therapeutic modality is firmly established by proteolysis targeting chimeras (PROTACs) that bring an E3 ubiquitin ligase in proximity to a target protein to induce ubiquitination and subsequent degradation of the target. The concept can be expanded to induce other post-translational modifications via the recruitment of different types of protein-modifying enzymes. To survey the human proteome for opportunities in proximity pharmacology, we systematically mapped non-catalytic drug binding pockets on the structure of protein-modifying enzymes available from the Protein Databank. In addition to binding sites exploited by previously reported ProxPharm compounds, we identified putative ligandable non-catalytic pockets in 236 kinases, 45 phosphatases, 37 deubiquitinases, 14 methyltransferases, 11 acetyltransferases, 13 glycosyltransferases, 4 deacetylases, 7 demethylases and 2 glycosidases, including cavities occupied by chemical matter that may serve as starting points for future ProxPharm compounds. This systematic survey confirms that proximity pharmacology is a versatile modality with largely unexplored and promising potential and reveals novel opportunities to pharmacologically rewire molecular circuitries. All data is available from the ProxyBind database at https://polymorph.sgc.utoronto.ca/proxybind/index.php.
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Lin X, Xiao M, Chen Z, Ding C, Zhang T, Li Q, Xu Y. Pancancer Analyses Reveal Genomics and Clinical Characteristics of the SETDB1 in Human Tumors. Journal of Oncology 2022; 2022:1-40. [PMID: 35656340 PMCID: PMC9152430 DOI: 10.1155/2022/6115878] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/17/2022] [Indexed: 12/03/2022]
Abstract
Background. Malignant tumor is one of the most common diseases that seriously affect human health. The prior literature has reported the biological function and potential therapeutic targets of SET domain bifurcated histone lysine methyltransferase 1 (SETDB1) as an oncogene. However, SETDB1 has rarely been analyzed from a pan-cancer perspective. Methods. Bioinformatics analysis tools and databases, including GeneCards, National Center for Biotechnology Information (NCBI), UniProt, Illustrator for Biological Sequences (IBS), Human Protein Atlas (HPA), GEPIA, TIMER2, Sangerbox 3.0, UALCAN, Kaplan-Meier (K-M) plotter, cBioPortal, Catalogue Of Somatic Mutations In Cancer (COSMIC), PhosphoSitePlus, TISIDB, STRING, and GeneMANIA, were utilized to clarify the biological functions and clinical significance of SETDB1 from a pan-cancer perspective. Results. In this study, the pan-cancer analysis demonstrated that SETDB1 showed significantly differential expression in most tumor tissues and paracancerous tissues, and SETDB1 expression was associated with clinicopathological features and clinical prognosis. We also found that SETDB1 mutations occurred in most tumors and were related to tumorigenesis. In addition, DNA methylation of SETDB1 primarily occurred at the cg10444928 site and was associated with prognosis in several human tumors. The predicted phosphorylation site of SETDB1 was Ser1006. We found that SETDB1 was significantly related to the specific tumor-infiltrating immune cell populations and expression of clinically targetable immune checkpoints and may be a promising immunotherapy target. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses also indicated that SETDB1 may function as crucial regulator in carcinogenesis of human cancers. Conclusions. SETDB1 is an important oncogene involved in tumorigenesis and tumor progression through different biological mechanisms. Furthermore, SETDB1 may be a potential therapeutic target for cancer treatment.
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Chen R, Ishak CA, De Carvalho DD. Endogenous Retroelements and the Viral Mimicry Response in Cancer Therapy and Cellular Homeostasis. Cancer Discov 2021; 11:2707-2725. [PMID: 34649957 DOI: 10.1158/2159-8290.cd-21-0506] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/14/2021] [Accepted: 07/08/2021] [Indexed: 11/16/2022]
Abstract
Features of the cancer epigenome distinguish cancers from their respective cell of origin and establish therapeutic vulnerabilities that can be exploited through pharmacologic inhibition of DNA- or histone-modifying enzymes. Epigenetic therapies converge with cancer immunotherapies through "viral mimicry," a cellular state of active antiviral response triggered by endogenous nucleic acids often derived from aberrantly transcribed endogenous retrotransposons. This review describes the initial characterization and expansion of viral mimicry-inducing approaches as well as features that "prime" cancers for viral mimicry induction. Increased understanding of viral mimicry in therapeutic contexts suggests potential physiologic roles in cellular homeostasis. SIGNIFICANCE: Recent literature establishes elevated cytosolic double strand RNA (dsRNA) levels as a cancer-specific therapeutic vulnerability that can be elevated by viral mimicry-inducing therapies beyond tolerable thresholds to induce antiviral signaling and increase dependence on dsRNA stress responses mediated by ADAR1. Improved understanding of viral mimicry signaling and tolerance mechanisms reveals synergistic treatment combinations with epigenetic therapies that include inhibition of BCL2, ADAR1, and immune checkpoint blockade. Further characterization of viral mimicry tolerance may identify contexts that maximize efficacy of conventional cancer therapies.
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Affiliation(s)
- Raymond Chen
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.,Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Charles A Ishak
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Daniel D De Carvalho
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada. .,Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
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