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Abstract
The epigenetic control of gene expression could be affected by addition and/or removal of post-translational modifications such as phosphorylation, acetylation and methylation of histone proteins, as well as methylation of DNA (5-methylation on cytosines). Misregulation of these modifications is associated with altered gene expression, resulting in various disease conditions. G9a belongs to the protein lysine methyltransferases that specifically methylates the K9 residue of histone H3, leading to suppression of several tumor suppressor genes. In this review, G9a functions, role in various diseases, structural biology aspects for inhibitor design, structure-activity relationship among the reported inhibitors are discussed which could aid in the design and development of potent G9a inhibitors for cancer treatment in the future.
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Ramya Chandar Charles M, Hsieh HP, Selvaraj Coumar M. Delineating the active site architecture of G9a lysine methyltransferase through substrate and inhibitor binding mode analysis: a molecular dynamics study. J Biomol Struct Dyn 2018; 37:2581-2592. [PMID: 30047835 DOI: 10.1080/07391102.2018.1491422] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mono- and di-methylation of the H3K9 residue in the histone tail by G9a lysine methyltransferase is associated with transcriptional suppression of genes. Here, we use molecular dynamics simulation and free energy calculations of five different modified/mutated G9a substrate peptides to elucidate the rationale behind the substrate binding to G9a. We also investigated the binding energy contribution based architecture of the active site of G9a to understand substrate and inhibitor binding. Wild-type peptide (H3K9) shows better binding affinity than mono- and di-methylated lysine (K9) and other modified peptides (K9A and R8A). Arg8 of the substrate peptide is crucial for determining the degree of conformational freedom/stability of the wild-type substrate peptide, as well as binding to G9a. Our results also suggest that the G9a active site is segregated into energy rich and low regions, and the energy rich region alone is used by the inhibitors for binding. These insights into the active site architecture should be taken into consideration in virtual screening experiments designed to discover novel inhibitors for G9a. In particular, compounds that could interact with the six residues of G9a - Asp1074, Asp1083, Leu1086, Asp1088, Tyr1154 and Phe1158 - should be preferentially tested in G9a inhibition biological assays. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | - Hsing-Pang Hsieh
- b Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhunan , Taiwan , ROC
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Prachayasittikul V, Prathipati P, Pratiwi R, Phanus-Umporn C, Malik AA, Schaduangrat N, Seenprachawong K, Wongchitrat P, Supokawej A, Prachayasittikul V, Wikberg JES, Nantasenamat C. Exploring the epigenetic drug discovery landscape. Expert Opin Drug Discov 2017; 12:345-362. [PMID: 28276705 DOI: 10.1080/17460441.2017.1295954] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
INTRODUCTION Epigenetic modification has been implicated in a wide range of diseases and the ability to modulate such systems is a lucrative therapeutic strategy in drug discovery. Areas covered: This article focuses on the concepts and drug discovery aspects of epigenomics. This is achieved by providing a survey of the following concepts: (i) factors influencing epigenetics, (ii) diseases arising from epigenetics, (iii) epigenetic enzymes as druggable targets along with coverage of existing FDA-approved drugs and pharmacological agents, and (iv) drug repurposing/repositioning as a means for rapid discovery of pharmacological agents targeting epigenetics. Expert opinion: Despite significant interests in targeting epigenetic modifiers as a therapeutic route, certain classes of target proteins are heavily studied while some are less characterized. Thus, such orphan target proteins are not yet druggable with limited report of active modulators. Current research points towards a great future with novel drugs directed to the many complex multifactorial diseases of humans, which are still often poorly understood and difficult to treat.
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Affiliation(s)
- Veda Prachayasittikul
- a Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Philip Prathipati
- b National Institutes of Biomedical Innovation, Health and Nutrition , Osaka , Japan
| | - Reny Pratiwi
- a Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Chuleeporn Phanus-Umporn
- a Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Aijaz Ahmad Malik
- a Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Nalini Schaduangrat
- a Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Kanokwan Seenprachawong
- c Department of Clinical Microscopy, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Prapimpun Wongchitrat
- d Center for Research and Innovation, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Aungkura Supokawej
- c Department of Clinical Microscopy, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Virapong Prachayasittikul
- e Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
| | - Jarl E S Wikberg
- f Department of Pharmaceutical Biosciences , Uppsala University , Uppsala , Sweden
| | - Chanin Nantasenamat
- a Center of Data Mining and Biomedical Informatics, Faculty of Medical Technology , Mahidol University , Bangkok , Thailand
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Maegley KA, Krivacic C, Bingham P, Liu W, Brooun A. Comparison of a High-Throughput Mass Spectrometry Method and Radioactive Filter Binding to Assay the Protein Methyltransferase PRMT5. Assay Drug Dev Technol 2016; 13:235-40. [PMID: 26065559 DOI: 10.1089/adt.2015.640] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Conformational remodeling of chromatin in cells is known to alter gene expression. The histone code hypothesis postulates that multiple modifications present on histone tails can regulate gene expression both through direct effects on chromatin compaction as well as through recruitment of unique complexes that signal specific downstream functions. Histone methylation is an important component of the histone code, and the dysregulation of histone methylation in disease makes methyltransferases and demethylases viable targets for drug discovery. We developed a biochemical assay platform, which takes advantage of the fact that protein methyltransferases (PMTs) all utilize the cofactor S-Adenosyl-L-methionine (SAM) as the methyl donor. The platform utilizes the High-throughput Mass Spectrometry (MS) technology to measure SAM and the S-Adenosyl-L-homocysteine product in a label-free manner. The platform has all the advantages of a label-free system coupled with the benefit of substrate agnostic measurements making it an ideal setup for PMT biochemical studies and drug discovery. In addition, MS is ideally suited for detecting multiple modification events within the same substrate. The ability to adjust the detection to monitor the methyl acceptor product allows for real-time measurements of multiple product species simultaneously, a distinct advantage over other commonly used assay formats.
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Affiliation(s)
- Karen A Maegley
- 1 Oncology Research Unit, Pfizer World Wide Research and Development , San Diego, California
| | - Cody Krivacic
- 1 Oncology Research Unit, Pfizer World Wide Research and Development , San Diego, California
| | - Patrick Bingham
- 1 Oncology Research Unit, Pfizer World Wide Research and Development , San Diego, California
| | - Wei Liu
- 2 Oncology Medicinal Chemistry, Pfizer World Wide Research and Development , San Diego, California
| | - Alexei Brooun
- 2 Oncology Medicinal Chemistry, Pfizer World Wide Research and Development , San Diego, California
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Chen S, Li L, Chen Y, Hu J, Liu J, Liu YC, Liu R, Zhang Y, Meng F, Zhu K, Lu J, Zheng M, Chen K, Zhang J, Jiang H, Yao Z, Luo C. Identification of Novel Disruptor of Telomeric Silencing 1-like (DOT1L) Inhibitors through Structure-Based Virtual Screening and Biological Assays. J Chem Inf Model 2016; 56:527-34. [PMID: 26914852 DOI: 10.1021/acs.jcim.5b00738] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Histone methyltransferases are involved in many important biological processes, and abnormalities in these enzymes are associated with tumorigenesis and progression. Disruptor of telomeric silencing 1-like (DOT1L), a key hub in histone lysine methyltransferases, has been reported to play an important role in the processes of mixed-lineage leukemia (MLL)-rearranged leukemias and validated to be a potential therapeutic target. In this study, we identified a novel DOT1L inhibitor, DC_L115 (CAS no. 1163729-79-0), by combining structure-based virtual screening with biochemical analyses. This potent inhibitor DC_L115 shows high inhibitory activity toward DOT1L (IC50 = 1.5 μM). Through a process of surface plasmon resonance-based binding assays, DC_L115 was founded to bind to DOT1L with a binding affinity of 0.6 μM in vitro. Moreover, this compound selectively inhibits MLL-rearranged cell proliferation with an IC50 value of 37.1 μM. We further predicted the binding modes of DC_L115 through molecular docking analysis and found that the inhibitor competitively occupies the binding site of S-adenosylmethionine. Overall, this study demonstrates the development of potent DOT1L inhibitors with novel scaffolds.
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Affiliation(s)
- Shijie Chen
- School of Life Science and Technology, Shanghai Tech University , Shanghai 200031, China.,Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Linjuan Li
- School of Life Science and Technology, Shanghai Tech University , Shanghai 200031, China.,Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Yantao Chen
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Junchi Hu
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Jingqiu Liu
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Yu-Chih Liu
- In Vitro Biology, Shanghai ChemPartner LifeScience Co., Ltd. , #5 Building, 998 Halei Road, Shanghai 201203, China
| | - Rongfeng Liu
- In Vitro Biology, Shanghai ChemPartner LifeScience Co., Ltd. , #5 Building, 998 Halei Road, Shanghai 201203, China
| | - Yuanyuan Zhang
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Fanwang Meng
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Kongkai Zhu
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Junyan Lu
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Mingyue Zheng
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Kaixian Chen
- School of Life Science and Technology, Shanghai Tech University , Shanghai 200031, China.,Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Jin Zhang
- Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai 200127, China
| | - Hualiang Jiang
- School of Life Science and Technology, Shanghai Tech University , Shanghai 200031, China.,Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
| | - Zhiyi Yao
- College of Chemical and Environmental Engineering, Shanghai Institute of Technology , Shanghai 210032, China
| | - Cheng Luo
- Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chongzhi Road, Shanghai 201203, China
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Hu H, Qian K, Ho MC, Zheng YG. Small Molecule Inhibitors of Protein Arginine Methyltransferases. Expert Opin Investig Drugs 2016; 25:335-58. [PMID: 26789238 DOI: 10.1517/13543784.2016.1144747] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Arginine methylation is an abundant posttranslational modification occurring in mammalian cells and catalyzed by protein arginine methyltransferases (PRMTs). Misregulation and aberrant expression of PRMTs are associated with various disease states, notably cancer. PRMTs are prominent therapeutic targets in drug discovery. AREAS COVERED The authors provide an updated review of the research on the development of chemical modulators for PRMTs. Great efforts are seen in screening and designing potent and selective PRMT inhibitors, and a number of micromolar and submicromolar inhibitors have been obtained for key PRMT enzymes such as PRMT1, CARM1, and PRMT5. The authors provide a focus on their chemical structures, mechanism of action, and pharmacological activities. Pros and cons of each type of inhibitors are also discussed. EXPERT OPINION Several key challenging issues exist in PRMT inhibitor discovery. Structural mechanisms of many PRMT inhibitors remain unclear. There lacks consistency in potency data due to divergence of assay methods and conditions. Physiologically relevant cellular assays are warranted. Substantial engagements are needed to investigate pharmacodynamics and pharmacokinetics of the new PRMT inhibitors in pertinent disease models. Discovery and evaluation of potent, isoform-selective, cell-permeable and in vivo-active PRMT modulators will continue to be an active arena of research in years ahead.
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Affiliation(s)
- Hao Hu
- a Department of Pharmaceutical and Biomedical Sciences , The University of Georgia , Athens , GA , USA
| | - Kun Qian
- a Department of Pharmaceutical and Biomedical Sciences , The University of Georgia , Athens , GA , USA
| | - Meng-Chiao Ho
- b Institute of Biological Chemistry , Academia Sinica , Nankang , Taipei , Taiwan
| | - Y George Zheng
- a Department of Pharmaceutical and Biomedical Sciences , The University of Georgia , Athens , GA , USA
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Andreoli F, Del Rio A. Computer-aided Molecular Design of Compounds Targeting Histone Modifying Enzymes. Comput Struct Biotechnol J 2015; 13:358-65. [PMID: 26082827 PMCID: PMC4459771 DOI: 10.1016/j.csbj.2015.04.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 04/24/2015] [Accepted: 04/30/2015] [Indexed: 02/06/2023] Open
Abstract
Growing evidences show that epigenetic mechanisms play crucial roles in the genesis and progression of many physiopathological processes. As a result, research in epigenetic grew at a fast pace in the last decade. In particular, the study of histone post-translational modifications encountered an extraordinary progression and many modifications have been characterized and associated to fundamental biological processes and pathological conditions. Histone modifications are the catalytic result of a large set of enzyme families that operate covalent modifications on specific residues at the histone tails. Taken together, these modifications elicit a complex and concerted processing that greatly contribute to the chromatin remodeling and may drive different pathological conditions, especially cancer. For this reason, several epigenetic targets are currently under validation for drug discovery purposes and different academic and industrial programs have been already launched to produce the first pre-clinical and clinical outcomes. In this scenario, computer-aided molecular design techniques are offering important tools, mainly as a consequence of the increasing structural information available for these targets. In this mini-review we will briefly discuss the most common types of known histone modifications and the corresponding operating enzymes by emphasizing the computer-aided molecular design approaches that can be of use to speed-up the efforts to generate new pharmaceutically relevant compounds.
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Affiliation(s)
- Federico Andreoli
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Alma Mater Studiorum, University of Bologna, Via S. Giacomo 14, 40126 Bologna, Italy
| | - Alberto Del Rio
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), Alma Mater Studiorum, University of Bologna, Via S. Giacomo 14, 40126 Bologna, Italy
- Institute of Organic Synthesis and Photoreactivity, National Research Council, Via P. Gobetti, 101 40129 Bologna, Italy
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Grech G, Zhan X, Yoo BC, Bubnov R, Hagan S, Danesi R, Vittadini G, Desiderio DM. EPMA position paper in cancer: current overview and future perspectives. EPMA J 2015; 6:9. [PMID: 25908947 PMCID: PMC4407842 DOI: 10.1186/s13167-015-0030-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 02/26/2015] [Indexed: 12/31/2022]
Abstract
At present, a radical shift in cancer treatment is occurring in terms of predictive, preventive, and personalized medicine (PPPM). Individual patients will participate in more aspects of their healthcare. During the development of PPPM, many rapid, specific, and sensitive new methods for earlier detection of cancer will result in more efficient management of the patient and hence a better quality of life. Coordination of the various activities among different healthcare professionals in primary, secondary, and tertiary care requires well-defined competencies, implementation of training and educational programs, sharing of data, and harmonized guidelines. In this position paper, the current knowledge to understand cancer predisposition and risk factors, the cellular biology of cancer, predictive markers and treatment outcome, the improvement in technologies in screening and diagnosis, and provision of better drug development solutions are discussed in the context of a better implementation of personalized medicine. Recognition of the major risk factors for cancer initiation is the key for preventive strategies (EPMA J. 4(1):6, 2013). Of interest, cancer predisposing syndromes in particular the monogenic subtypes that lead to cancer progression are well defined and one should focus on implementation strategies to identify individuals at risk to allow preventive measures and early screening/diagnosis. Implementation of such measures is disturbed by improper use of the data, with breach of data protection as one of the risks to be heavily controlled. Population screening requires in depth cost-benefit analysis to justify healthcare costs, and the parameters screened should provide information that allow an actionable and deliverable solution, for better healthcare provision.
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Affiliation(s)
- Godfrey Grech
- Department of Pathology, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Xianquan Zhan
- Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, China
| | - Byong Chul Yoo
- Colorectal Cancer Branch, Division of Translational and Clinical Research I, Research Institute, National Cancer Center, Gyeonggi, 410-769 Republic of Korea
| | - Rostyslav Bubnov
- Clinical Hospital 'Pheophania' of State Management of Affairs Department, Kyiv, Ukraine ; Zabolotny Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Suzanne Hagan
- Dept of Life Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Romano Danesi
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | | | - Dominic M Desiderio
- Department of Neurology, University of Tennessee Center for Health Science, Memphis, USA
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Knapp S, Weinmann H. Small-molecule modulators for epigenetics targets. ChemMedChem 2013; 8:1885-91. [PMID: 24127276 DOI: 10.1002/cmdc.201300344] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Indexed: 01/08/2023]
Abstract
A capital conference: Influencing epigenetic mechanisms may be highly relevant for future therapies of various diseases such as cancer, inflammation, and metabolic disorders. Leading experts in the field gathered in Berlin on June 5-6, 2013 at a Bayer HealthCare Life Science Workshop to share recent success stories and to discuss future trends.
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Affiliation(s)
- Stefan Knapp
- Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus Research Building and Target Discovery Institute, Roosevelt Drive, Headington, Oxford, OX3 7FZ (UK)
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Abstract
The protein methyltransferases (PMT) constitute a large and important class of enzymes that catalyze site-specific methylation of lysine or arginine residues on histones and other proteins. Site-specific histone methylation is a critical component of chromatin regulation of gene transcription-a pathway that is often genetically altered in human cancers. Oncogenic alterations (e.g., mutations, chromosomal translocations, and others) of PMTs, or of associated proteins, have been found to confer unique dependencies of cancer cells on the activity of specific PMTs. Examples of potent, selective small-molecule inhibitors of specific PMTs are reviewed that have been shown to kill cancers cells bearing such oncogenic alterations, while having minimal effect on proliferation of nonaltered cells. Selective inhibitors of the PMTs, DOT1L and EZH2, have entered phase I clinical studies and additional examples of selective PMT inhibitors are likely to enter the clinic soon. The current state of efforts toward clinical testing of selective PMT inhibitors as personalized cancer therapeutics is reviewed here.
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Basavapathruni A, Jin L, Daigle SR, Majer CRA, Therkelsen CA, Wigle TJ, Kuntz KW, Chesworth R, Pollock RM, Scott MP, Moyer MP, Richon VM, Copeland RA, Olhava EJ. Conformational adaptation drives potent, selective and durable inhibition of the human protein methyltransferase DOT1L. Chem Biol Drug Des 2012; 80:971-80. [PMID: 22978415 DOI: 10.1111/cbdd.12050] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
DOT1L is the human protein methyltransferase responsible for catalyzing the methylation of histone H3 on lysine 79 (H3K79). The ectopic activity of DOT1L, associated with the chromosomal translocation that is a universal hallmark of MLL-rearranged leukemia, is a required driver of leukemogenesis in this malignancy. Here, we present studies on the structure-activity relationship of aminonucleoside-based DOT1L inhibitors. Within this series, we find that improvements in target enzyme affinity and selectivity are driven entirely by diminution of the dissociation rate constant for the enzyme-inhibitor complex, leading to long residence times for the binary complex. The biochemical K(i) and residence times measured for these inhibitors correlate well with their effects on intracellular H3K79 methylation and MLL-rearranged leukemic cell killing. Crystallographic studies reveal a conformational adaptation mechanism associated with high-affinity inhibitor binding and prolonged residence time; these studies also suggest that conformational adaptation likewise plays a critical role in natural ligand interactions with the enzyme, hence, facilitating enzyme turnover. These results provide critical insights into the role of conformational adaptation in the enzymatic mechanism of catalysis and in pharmacologic intervention for DOT1L and other members of this enzyme class.
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Knutson SK, Wigle TJ, Warholic NM, Sneeringer CJ, Allain CJ, Klaus CR, Sacks JD, Raimondi A, Majer CR, Song J, Scott MP, Jin L, Smith JJ, Olhava EJ, Chesworth R, Moyer MP, Richon VM, Copeland RA, Keilhack H, Pollock RM, Kuntz KW. A selective inhibitor of EZH2 blocks H3K27 methylation and kills mutant lymphoma cells. Nat Chem Biol 2012; 8:890-6. [PMID: 23023262 DOI: 10.1038/nchembio.1084] [Citation(s) in RCA: 609] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Accepted: 07/13/2012] [Indexed: 12/24/2022]
Abstract
EZH2 catalyzes trimethylation of histone H3 lysine 27 (H3K27). Point mutations of EZH2 at Tyr641 and Ala677 occur in subpopulations of non-Hodgkin's lymphoma, where they drive H3K27 hypertrimethylation. Here we report the discovery of EPZ005687, a potent inhibitor of EZH2 (K(i) of 24 nM). EPZ005687 has greater than 500-fold selectivity against 15 other protein methyltransferases and has 50-fold selectivity against the closely related enzyme EZH1. The compound reduces H3K27 methylation in various lymphoma cells; this translates into apoptotic cell killing in heterozygous Tyr641 or Ala677 mutant cells, with minimal effects on the proliferation of wild-type cells. These data suggest that genetic alteration of EZH2 (for example, mutations at Tyr641 or Ala677) results in a critical dependency on enzymatic activity for proliferation (that is, the equivalent of oncogene addiction), thus portending the clinical use of EZH2 inhibitors for cancers in which EZH2 is genetically altered.
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