1
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Lama D, Vosselman T, Sahin C, Liaño-Pons J, Cerrato CP, Nilsson L, Teilum K, Lane DP, Landreh M, Arsenian Henriksson M. A druggable conformational switch in the c-MYC transactivation domain. Nat Commun 2024; 15:1865. [PMID: 38424045 PMCID: PMC10904854 DOI: 10.1038/s41467-024-45826-7] [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: 01/12/2023] [Accepted: 02/06/2024] [Indexed: 03/02/2024] Open
Abstract
The c-MYC oncogene is activated in over 70% of all human cancers. The intrinsic disorder of the c-MYC transcription factor facilitates molecular interactions that regulate numerous biological pathways, but severely limits efforts to target its function for cancer therapy. Here, we use a reductionist strategy to characterize the dynamic and structural heterogeneity of the c-MYC protein. Using probe-based Molecular Dynamics (MD) simulations and machine learning, we identify a conformational switch in the c-MYC amino-terminal transactivation domain (termed coreMYC) that cycles between a closed, inactive, and an open, active conformation. Using the polyphenol epigallocatechin gallate (EGCG) to modulate the conformational landscape of coreMYC, we show through biophysical and cellular assays that the induction of a closed conformation impedes its interactions with the transformation/transcription domain-associated protein (TRRAP) and the TATA-box binding protein (TBP) which are essential for the transcriptional and oncogenic activities of c-MYC. Together, these findings provide insights into structure-activity relationships of c-MYC, which open avenues towards the development of shape-shifting compounds to target c-MYC as well as other disordered transcription factors for cancer treatment.
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Affiliation(s)
- Dilraj Lama
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden.
| | - Thibault Vosselman
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden
| | - Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden
- Department of Biology, Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Judit Liaño-Pons
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden
| | - Carmine P Cerrato
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden
| | - Lennart Nilsson
- Department of Biosciences and Nutrition, Karolinska Institutet, SE-14813, Huddinge, Sweden
| | - Kaare Teilum
- Department of Biology, Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - David P Lane
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden.
- Department of Cell- and Molecular Biology, Uppsala University, SE-751 24, Uppsala, Sweden.
| | - Marie Arsenian Henriksson
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, SE-17165, Stockholm, Sweden.
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, SE-221 00, Lund, Sweden.
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2
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Gunasinghe KJ, Rahman T, Chee Wezen X. Unraveling the Behavior of Intrinsically Disordered Protein c-Myc: A Study Utilizing Gaussian-Accelerated Molecular Dynamics. ACS OMEGA 2024; 9:2250-2262. [PMID: 38250404 PMCID: PMC10795134 DOI: 10.1021/acsomega.3c05822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 11/02/2023] [Accepted: 11/21/2023] [Indexed: 01/23/2024]
Abstract
The protein c-Myc is a transcription factor that remains largely intrinsically disordered and is known to be involved in various biological processes and is overexpressed in various cancers, making it an attractive drug target. However, intrinsically disordered proteins such as c-Myc do not show funnel-like basins in their free-energy landscapes; this makes their druggability a challenge. For the first time, we propose a heterodimer model of c-Myc/Max in full length in this work. We used Gaussian-accelerated molecular dynamics (GaMD) simulations to explore the behavior of c-Myc and its various regions, including the transactivation domain (TAD) and the basic helix-loop-helix-leucine-zipper (bHLH-Zipper) motif in three different conformational states: (a) monomeric c-Myc, (b) c-Myc when bound to its partner protein, Max, and (c) when Max was removed after binding. We analyzed the GaMD trajectories using root-mean-square deviation (RMSD), radius of gyration, root-mean-square fluctuation, and free-energy landscape (FEL) calculations to elaborate the behaviors of these regions. The results showed that the monomeric c-Myc structure showed a higher RMSD fluctuation as compared with the c-Myc/Max heterodimer in the bHLH-Zipper motif. This indicated that the bHLH-Zipper motif of c-Myc is more stable when it is bound to Max. The TAD region in both monomeric and Max-bound states showed similar plasticity in terms of RMSD. We also conducted residue decomposition calculations and showed that the c-Myc and Max interaction could be driven mainly by electrostatic interactions and the residues Arg299, Ile403, and Leu420 seemed to play important roles in the interaction. Our work provides insights into the behavior of c-Myc and its regions that could support the development of drugs that target c-Myc and other intrinsically disordered proteins.
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Affiliation(s)
| | - Taufiq Rahman
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Xavier Chee Wezen
- Faculty
of Engineering, Computing and Science, Swinburne
University of Technology Sarawak, Kuching 93350, Malaysia
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3
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Liu F, Liao Z, Zhang Z. MYC in liver cancer: mechanisms and targeted therapy opportunities. Oncogene 2023; 42:3303-3318. [PMID: 37833558 DOI: 10.1038/s41388-023-02861-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 09/28/2023] [Accepted: 10/03/2023] [Indexed: 10/15/2023]
Abstract
MYC, a major oncogenic transcription factor, regulates target genes involved in various pathways such as cell proliferation, metabolism and immune evasion, playing a critical role in the tumor initiation and development in multiple types of cancer. In liver cancer, MYC and its signaling pathways undergo significant changes, exerting a profound impact on liver cancer progression, including tumor proliferation, metastasis, dedifferentiation, metabolism, immune microenvironment, and resistance to comprehensive therapies. This makes MYC an appealing target, despite it being previously considered an undruggable protein. In this review, we discuss the role and mechanisms of MYC in liver physiology, chronic liver diseases, hepatocarcinogenesis, and liver cancer progression, providing a theoretical basis for targeting MYC as an ideal therapeutic target for liver cancer. We also summarize and prospect the strategies for targeting MYC, including direct and indirect approaches to abolish the oncogenic function of MYC in liver cancer.
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Affiliation(s)
- Furong Liu
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, China
- Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Wuhan, Hubei, 430030, China
- Key Laboratory of Organ Transplantation, Ministry of Education; NHC Key Laboratory of Organ Transplantation; Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China
| | - Zhibin Liao
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, China
- Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Wuhan, Hubei, 430030, China
- Key Laboratory of Organ Transplantation, Ministry of Education; NHC Key Laboratory of Organ Transplantation; Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China
| | - Zhanguo Zhang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, China.
- Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Wuhan, Hubei, 430030, China.
- Key Laboratory of Organ Transplantation, Ministry of Education; NHC Key Laboratory of Organ Transplantation; Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, China.
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4
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Altiner P, Çınaroğlu SS, Timucin AC, Timucin E. Computational completion of the Aurora interaction region of N-Myc in the Aurora a kinase complex. Sci Rep 2023; 13:18399. [PMID: 37884585 PMCID: PMC10603048 DOI: 10.1038/s41598-023-45272-3] [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: 07/26/2023] [Accepted: 10/17/2023] [Indexed: 10/28/2023] Open
Abstract
Inhibiting protein-protein interactions of the Myc family is a viable pharmacological strategy for modulation of the levels of Myc oncoproteins in cancer. Aurora A kinase (AurA) and N-Myc interaction is one of the most attractive targets of this strategy because formation of this complex blocks proteasomal degradation of N-Myc in neuroblastoma. Two crystallization studies have captured this complex (PDB IDs: 5g1x, 7ztl), partially resolving the AurA interaction region (AIR) of N-Myc. Prompted by the missing N-Myc fragment in these crystal structures, we modeled the complete structure between AurA and N-Myc, and comprehensively analyzed how the incomplete and complete N-Myc behave in complex by molecular dynamics simulations. Molecular dynamics simulations of the incomplete PDB complex (5g1x) repeatedly showed partial dissociation of the short N-Myc fragment (61-89) from the kinase. The missing N-Myc (19-60) fragment was modeled utilizing the N-terminal lobe of AurA as the protein-protein interaction surface, wherein TPX2, a well-known partner of AurA, also binds. Binding free energy calculations along with flexibility analysis confirmed that the complete AIR of N-Myc stabilizes the complex, accentuating the N-terminal lobe of AurA as a binding site for the missing N-Myc fragment (19-60). We further generated additional models consisting of only the missing N-Myc (19-60), and the fused form of TPX2 (7-43) and N-Myc (61-89). These partners also formed more stable interactions with the N-terminal lobe of AurA than did the incomplete N-Myc fragment (61-89) in the 5g1x complex. Altogether, this study provides structural insights into the involvement of the N-terminus of the AIR of N-Myc and the N-terminal lobe of AurA in formation of a stable complex, reflecting its potential for effective targeting of N-Myc.
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Affiliation(s)
- Pinar Altiner
- Institut de Pharmacologie et de Biologie Structurale (IPBS), CNRS, Université Toulouse III - Paul Sabatier (UT3), 31077, Toulouse, France
| | | | - Ahmet Can Timucin
- Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Sciences, Acibadem University, 34752, Istanbul, Turkey.
| | - Emel Timucin
- Department of Biostatistics and Medical Informatics, School of Medicine, Acibadem University, 34752, Istanbul, Turkey.
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5
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Moyers BA, Partridge EC, Mackiewicz M, Betti MJ, Darji R, Meadows SK, Newberry KM, Brandsmeier LA, Wold BJ, Mendenhall EM, Myers RM. Characterization of human transcription factor function and patterns of gene regulation in HepG2 cells. Genome Res 2023; 33:gr.278205.123. [PMID: 37852782 PMCID: PMC10760452 DOI: 10.1101/gr.278205.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/13/2023] [Indexed: 10/20/2023]
Abstract
Transcription factors (TFs) are trans-acting proteins that bind cis-regulatory elements (CREs) in DNA to control gene expression. Here, we analyzed the genomic localization profiles of 529 sequence-specific TFs and 151 cofactors and chromatin regulators in the human cancer cell line HepG2, for a total of 680 broadly termed DNA-associated proteins (DAPs). We used this deep collection to model each TF's impact on gene expression, and identified a cohort of 26 candidate transcriptional repressors. We examine high occupancy target (HOT) sites in the context of three-dimensional genome organization and show biased motif placement in distal-promoter connections involving HOT sites. We also found a substantial number of closed chromatin regions with multiple DAPs bound, and explored their properties, finding that a MAFF/MAFK TF pair correlates with transcriptional repression. Altogether, these analyses provide novel insights into the regulatory logic of the human cell line HepG2 genome and show the usefulness of large genomic analyses for elucidation of individual TF functions.
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Affiliation(s)
- Belle A Moyers
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, USA
| | | | - Mark Mackiewicz
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, USA
| | - Michael J Betti
- Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
| | - Roshan Darji
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, USA
| | - Sarah K Meadows
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, USA
| | | | | | - Barbara J Wold
- Merkin Institute for Translational Research, California Institute of Technology, Pasadena, California 91125, USA
| | - Eric M Mendenhall
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, USA;
| | - Richard M Myers
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama 35806, USA;
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6
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Ji F, Zhang J, Liu N, Gu Y, Zhang Y, Huang P, Zhang N, Lin S, Pan R, Meng Z, Feng XH, Roessler S, Zheng X, Ji J. Blocking hepatocarcinogenesis by a cytochrome P450 family member with female-preferential expression. Gut 2022; 71:2313-2324. [PMID: 34996827 DOI: 10.1136/gutjnl-2021-326050] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 12/21/2021] [Indexed: 12/13/2022]
Abstract
OBJECTS The incidence of hepatocellular carcinoma (HCC) shows an obvious male dominance in rodents and humans. We aimed to identify the key autosomal liver-specific sex-related genes and investigate their roles in hepatocarcinogenesis. DESIGN Two HCC cohorts (n=551) with available transcriptome and metabolome data were used. Class comparisons of omics data and ingenuity pathway analysis were performed to explore sex-related molecules and their associated functions. Functional assays were employed to investigate roles of the key candidates, including cellular assays, molecular assays and multiple orthotopic HCC mouse models. RESULTS A global comparison of multiple omics data revealed 861 sex-related molecules in non-tumour liver tissues between female and male HCC patients, which denoted a significant suppression of cancer-related diseases and functions in female liver than male. A member of cytochrome P450 family, CYP39A1, was one of the top liver-specific candidates with significantly higher levels in female vs male liver. In HCC tumours, CYP39A1 expression was dramatically reduced in over 90% HCC patients. Exogenous CYP39A1 significantly blocked tumour formation in both female and male mice and partially reduced the sex disparity of hepatocarcinogenesis. The HCC suppressor role of CYP39A1 did not rely on its known P450 enzyme activity but its C-terminal region, by which CYP39A1 impeded the transcriptional activation activity of c-Myc, leading to a significant inhibition of hepatocarcinogenesis. CONCLUSIONS The liver-specific CYP39A1 with female-preferential expression was a strong suppressor of HCC development. Strategies to up-regulate CYP39A1 might be promising methods for HCC treatment in both women and men in future.
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Affiliation(s)
- Fubo Ji
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jianjuan Zhang
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
| | - Niya Liu
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yuanzhuo Gu
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yan Zhang
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
| | - Peipei Huang
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
| | - Nachuan Zhang
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
| | - Shengda Lin
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ran Pan
- Department of Pathology and Pathophysiology, Zhejiang Provincial Key Laboratory of Pancreatic Disease, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zhuoxian Meng
- Department of Pathology and Pathophysiology, Zhejiang Provincial Key Laboratory of Pancreatic Disease, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xin-Hua Feng
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China.,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China.,Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang, China
| | - Stephanie Roessler
- Institute of Pathology, Heidelberg University Hospital, Heidelberg, Germany
| | - Xin Zheng
- Taoharmony Biotech L.L.C, Hangzhou, Zhejiang, China
| | - Junfang Ji
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China .,Cancer Center, Zhejiang University, Hangzhou, Zhejiang, China
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7
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Wei Y, Redel C, Ahlner A, Lemak A, Johansson-Åkhe I, Houliston S, Kenney TMG, Tamachi A, Morad V, Duan S, Andrews DW, Wallner B, Sunnerhagen M, Arrowsmith CH, Penn LZ. The MYC oncoprotein directly interacts with its chromatin cofactor PNUTS to recruit PP1 phosphatase. Nucleic Acids Res 2022; 50:3505-3522. [PMID: 35244724 PMCID: PMC8989513 DOI: 10.1093/nar/gkac138] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 01/11/2022] [Accepted: 02/28/2022] [Indexed: 02/07/2023] Open
Abstract
Despite MYC dysregulation in most human cancers, strategies to target this potent oncogenic driver remain an urgent unmet need. Recent evidence shows the PP1 phosphatase and its regulatory subunit PNUTS control MYC phosphorylation, chromatin occupancy, and stability, however the molecular basis remains unclear. Here we demonstrate that MYC interacts directly with PNUTS through the MYC homology Box 0 (MB0), a highly conserved region recently shown to be important for MYC oncogenic activity. By NMR we identified a distinct peptide motif within MB0 that interacts with PNUTS residues 1–148, a functional unit, here termed PNUTS amino-terminal domain (PAD). Using NMR spectroscopy we determined the solution structure of PAD, and characterised its MYC-binding patch. Point mutations of residues at the MYC-PNUTS interface significantly weaken their interaction both in vitro and in vivo, leading to elevated MYC phosphorylation. These data demonstrate that the MB0 region of MYC directly interacts with the PAD of PNUTS, which provides new insight into the control mechanisms of MYC as a regulator of gene transcription and a pervasive cancer driver.
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Affiliation(s)
- Yong Wei
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada.,Sunnybrook Research Institute, 2075 Bayview Ave. Toronto, ON, M4N 3M5, Canada
| | - Cornelia Redel
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Alexandra Ahlner
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Alexander Lemak
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada
| | - Isak Johansson-Åkhe
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Scott Houliston
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada
| | - Tristan M G Kenney
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Aaliya Tamachi
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada
| | - Vivian Morad
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | | | - David W Andrews
- Sunnybrook Research Institute, 2075 Bayview Ave. Toronto, ON, M4N 3M5, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Björn Wallner
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Maria Sunnerhagen
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Cheryl H Arrowsmith
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Linda Z Penn
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
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8
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PHA-680626 Is an Effective Inhibitor of the Interaction between Aurora-A and N-Myc. Int J Mol Sci 2021; 22:ijms222313122. [PMID: 34884931 PMCID: PMC8658095 DOI: 10.3390/ijms222313122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/26/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022] Open
Abstract
Neuroblastoma is a severe childhood disease, accounting for ~10% of all infant cancers. The amplification of the MYCN gene, coding for the N-Myc transcription factor, is an essential marker correlated with tumor progression and poor prognosis. In neuroblastoma cells, the mitotic kinase Aurora-A (AURKA), also frequently overexpressed in cancer, prevents N-Myc degradation by directly binding to a highly conserved N-Myc region. As a result, elevated levels of N-Myc are observed. During recent years, it has been demonstrated that some ATP competitive inhibitors of AURKA also cause essential conformational changes in the structure of the activation loop of the kinase that prevents N-Myc binding, thus impairing the formation of the AURKA/N-Myc complex. In this study, starting from a screening of crystal structures of AURKA in complexes with known inhibitors, we identified additional compounds affecting the conformation of the kinase activation loop. We assessed the ability of such compounds to disrupt the interaction between AURKA and N-Myc in vitro, using Surface Plasmon Resonance competition assays, and in tumor cell lines overexpressing MYCN, by performing Proximity Ligation Assays. Finally, their effects on N-Myc cellular levels and cell viability were investigated. Our results identify PHA-680626 as an amphosteric inhibitor both in vitro and in MYCN overexpressing cell lines, thus expanding the repertoire of known conformational disrupting inhibitors of the AURKA/N-Myc complex and confirming that altering the conformation of the activation loop of AURKA with a small molecule is an effective strategy to destabilize the AURKA/N-Myc interaction in neuroblastoma cancer cells.
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9
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Target-binding behavior of IDPs via pre-structured motifs. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 183:187-247. [PMID: 34656329 DOI: 10.1016/bs.pmbts.2021.07.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Pre-Structured Motifs (PreSMos) are transient secondary structures observed in many intrinsically disordered proteins (IDPs) and serve as protein target-binding hot spots. The prefix "pre" highlights that PreSMos exist a priori in the target-unbound state of IDPs as the active pockets of globular proteins pre-exist before target binding. Therefore, a PreSMo is an "active site" of an IDP; it is not a spatial pocket, but rather a secondary structural motif. The classical and perhaps the most effective approach to understand the function of a protein has been to determine and investigate its structure. Ironically or by definition IDPs do not possess structure (here structure refers to tertiary structure only). Are IDPs then entirely structureless? The PreSMos provide us with an atomic-resolution answer to this question. For target binding, IDPs do not rely on the spatial pockets afforded by tertiary or higher structures. Instead, they utilize the PreSMos possessing particular conformations that highly presage the target-bound conformations. PreSMos are recognized or captured by targets via conformational selection (CS) before their conformations eventually become stabilized via structural induction into more ordered bound structures. Using PreSMos, a number of, if not all, IDPs can bind targets following a sequential pathway of CS followed by an induced fit (IF). This chapter presents several important PreSMos implicated in cancers, neurodegenerative diseases, and other diseases along with discussions on their conformational details that mediate target binding, a structural rationale for unstructured proteins.
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10
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Ashrafizadeh M, Zarabi A, Hushmandi K, Moghadam ER, Hashemi F, Daneshi S, Hashemi F, Tavakol S, Mohammadinejad R, Najafi M, Dudha N, Garg M. C-Myc Signaling Pathway in Treatment and Prevention of Brain Tumors. Curr Cancer Drug Targets 2021; 21:2-20. [PMID: 33069197 DOI: 10.2174/1568009620666201016121005] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/26/2020] [Accepted: 09/07/2020] [Indexed: 12/16/2022]
Abstract
Brain tumors are responsible for high morbidity and mortality worldwide. Several factors such as the presence of blood-brain barrier (BBB), sensitive location in the brain, and unique biological features challenge the treatment of brain tumors. The conventional drugs are no longer effective in the treatment of brain tumors, and scientists are trying to find novel therapeutics for brain tumors. In this way, identification of molecular pathways can facilitate finding an effective treatment. c-Myc is an oncogene signaling pathway capable of regulation of biological processes such as apoptotic cell death, proliferation, survival, differentiation, and so on. These pleiotropic effects of c-Myc have resulted in much fascination with its role in different cancers, particularly brain tumors. In the present review, we aim to demonstrate the upstream and down-stream mediators of c-Myc in brain tumors such as glioma, glioblastoma, astrocytoma, and medulloblastoma. The capacity of c-Myc as a prognostic factor in brain tumors will be investigated. Our goal is to define an axis in which the c-Myc signaling pathway plays a crucial role and to provide direction for therapeutic targeting in these signaling networks in brain tumors.
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Affiliation(s)
- Milad Ashrafizadeh
- Faculty of Engineering and Natural Sciences, Sabanci University, Orta Mahalle, Universite Caddesi No. 27, Orhanli, Tuzla, 34956 Istanbul, Turkey
| | - Ali Zarabi
- Sabanci University Nanotechnology Research and Application Center (SUNUM), Tuzla, 34956, Istanbul, Turkey
| | - Kiavash Hushmandi
- Department of Food Hygiene and Quality Control, Division of Epidemiology & Zoonoses, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - Ebrahim Rahmani Moghadam
- Department of Anatomical sciences, School of Medicine, Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farid Hashemi
- DVM. Graduated, Young Researcher and Elite Club, Kazerun Branch, Islamic Azad University, Kazeroon, Iran
| | - Salman Daneshi
- Department of Public Health, School of Health, Jiroft University of Medical Sciences, Jiroft, Iran
| | - Fardin Hashemi
- Student Research Committee, Department of physiotherapy, Faculty of rehabilitation, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Shima Tavakol
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran
| | - Reza Mohammadinejad
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman 7619813159, Iran
| | - Masoud Najafi
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Namrata Dudha
- Department of Biotechnology and Microbiology, School of Sciences, Noida International University, Gautam Budh Nagar, Uttar Pradesh, India
| | - Manoj Garg
- Amity of Molecular Medicine and Stem cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida-201313, India
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11
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Liang J, Xia L, Oyang L, Lin J, Tan S, Yi P, Han Y, Luo X, Wang H, Tang L, Pan Q, Tian Y, Rao S, Su M, Shi Y, Cao D, Zhou Y, Liao Q. The functions and mechanisms of prefoldin complex and prefoldin-subunits. Cell Biosci 2020; 10:87. [PMID: 32699605 PMCID: PMC7370476 DOI: 10.1186/s13578-020-00446-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/15/2020] [Indexed: 12/26/2022] Open
Abstract
The correct folding is a key process for a protein to acquire its functional structure and conformation. Prefoldin is a well-known chaperone protein that regulates the correct folding of proteins. Prefoldin plays a crucial role in the pathogenesis of common neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, and Huntington's disease). The important role of prefoldin in emerging fields (such as nanoparticles, biomaterials) and tumors has attracted widespread attention. Also, each of the prefoldin subunits has different and independent functions from the prefoldin complex. It has abnormal expression in different tumors and plays an important role in tumorigenesis and development, especially c-Myc binding protein MM-1. MM-1 can inhibit the activity of c-Myc through various mechanisms to regulate tumor growth. Therefore, an in-depth analysis of the complex functions of prefoldin and their subunits is helpful to understand the mechanisms of protein misfolding and the pathogenesis of diseases caused by misfolded aggregation.
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Affiliation(s)
- Jiaxin Liang
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Longzheng Xia
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Linda Oyang
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Jinguan Lin
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Shiming Tan
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Pin Yi
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Yaqian Han
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Xia Luo
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Hui Wang
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Lu Tang
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
- Department of Medical Microbiology Immunology & Cell Biology, Simmons Cancer Institute, Southern Illinois University School of Medicine, 913 N. Rutledge Street, Springfield, IL 62794 USA
| | - Qing Pan
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
- Department of Medical Microbiology Immunology & Cell Biology, Simmons Cancer Institute, Southern Illinois University School of Medicine, 913 N. Rutledge Street, Springfield, IL 62794 USA
| | - Yutong Tian
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
- Department of Medical Microbiology Immunology & Cell Biology, Simmons Cancer Institute, Southern Illinois University School of Medicine, 913 N. Rutledge Street, Springfield, IL 62794 USA
| | - Shan Rao
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Min Su
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Yingrui Shi
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Deliang Cao
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
- Department of Medical Microbiology Immunology & Cell Biology, Simmons Cancer Institute, Southern Illinois University School of Medicine, 913 N. Rutledge Street, Springfield, IL 62794 USA
| | - Yujuan Zhou
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
| | - Qianjin Liao
- Hunan Key Laboratory of Translational Radiation Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 283 Tongzipo Road, Changsha, 410013 Hunan China
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12
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Multiple direct interactions of TBP with the MYC oncoprotein. Nat Struct Mol Biol 2019; 26:1035-1043. [DOI: 10.1038/s41594-019-0321-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 09/25/2019] [Indexed: 01/07/2023]
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13
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Kumar D, Sharma N, Giri R. Therapeutic Interventions of Cancers Using Intrinsically Disordered Proteins as Drug Targets: c-Myc as Model System. Cancer Inform 2017; 16:1176935117699408. [PMID: 28469390 PMCID: PMC5392011 DOI: 10.1177/1176935117699408] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 02/20/2017] [Indexed: 12/29/2022] Open
Abstract
The concept of protein intrinsic disorder has taken the driving seat to understand regulatory proteins in general. Reports suggest that in mammals nearly 75% of signalling proteins contain long disordered regions with greater than 30 amino acid residues. Therefore, intrinsically disordered proteins (IDPs) have been implicated in several human diseases and should be considered as potential novel drug targets. Moreover, intrinsic disorder provides a huge multifunctional capability to hub proteins such as c-Myc and p53. c-Myc is the hot spot for understanding and developing therapeutics against cancers and cancer stem cells. Our past understanding is mainly based on in vitro and in vivo experiments conducted using c-Myc as whole protein. Using the reductionist approach, c-Myc oncoprotein has been divided into structured and disordered domains. A wealth of data is available dealing with the structured perspectives of c-Myc, but understanding c-Myc in terms of disordered domains has just begun. Disorderness provides enormous flexibility to proteins in general for binding to numerous partners. Here, we have reviewed the current progress on understanding c-Myc using the emerging concept of IDPs.
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Affiliation(s)
- Deepak Kumar
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
| | - Nitin Sharma
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
| | - Rajanish Giri
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
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Richards MW, Burgess SG, Poon E, Carstensen A, Eilers M, Chesler L, Bayliss R. Structural basis of N-Myc binding by Aurora-A and its destabilization by kinase inhibitors. Proc Natl Acad Sci U S A 2016; 113:13726-13731. [PMID: 27837025 PMCID: PMC5137718 DOI: 10.1073/pnas.1610626113] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Myc family proteins promote cancer by inducing widespread changes in gene expression. Their rapid turnover by the ubiquitin-proteasome pathway is regulated through phosphorylation of Myc Box I and ubiquitination by the E3 ubiquitin ligase SCFFbxW7 However, N-Myc protein (the product of the MYCN oncogene) is stabilized in neuroblastoma by the protein kinase Aurora-A in a manner that is sensitive to certain Aurora-A-selective inhibitors. Here we identify a direct interaction between the catalytic domain of Aurora-A and a site flanking Myc Box I that also binds SCFFbxW7 We determined the crystal structure of the complex between Aurora-A and this region of N-Myc to 1.72-Å resolution. The structure indicates that the conformation of Aurora-A induced by compounds such as alisertib and CD532 is not compatible with the binding of N-Myc, explaining the activity of these compounds in neuroblastoma cells and providing a rational basis for the design of cancer therapeutics optimized for destabilization of the complex. We also propose a model for the stabilization mechanism in which binding to Aurora-A alters how N-Myc interacts with SCFFbxW7 to disfavor the generation of Lys48-linked polyubiquitin chains.
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Affiliation(s)
- Mark W Richards
- Astbury Centre for Structural and Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
- Cancer Research UK Leeds Centre, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Selena G Burgess
- Astbury Centre for Structural and Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
- Cancer Research UK Leeds Centre, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Evon Poon
- Division of Clinical Studies and Cancer Therapeutics, The Institute of Cancer Research, The Royal Marsden National Health Service Trust, Belmont, Sutton, Surrey SM2 5NG, United Kingdom
| | - Anne Carstensen
- Theodor Boveri Institute, University of Würzburg, 97074 Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University of Würzburg, 97074 Würzburg, Germany
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Martin Eilers
- Theodor Boveri Institute, University of Würzburg, 97074 Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University of Würzburg, 97074 Würzburg, Germany
- Department of Biochemistry and Molecular Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Louis Chesler
- Division of Clinical Studies and Cancer Therapeutics, The Institute of Cancer Research, The Royal Marsden National Health Service Trust, Belmont, Sutton, Surrey SM2 5NG, United Kingdom
| | - Richard Bayliss
- Astbury Centre for Structural and Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom;
- Cancer Research UK Leeds Centre, University of Leeds, Leeds LS2 9JT, United Kingdom
- Department of Cancer Studies, University of Leicester, Leicester LE1 9HN, United Kingdom
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15
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Yang T, Song B, Zhang J, Yang GS, Zhang H, Yu WF, Wu MC, Lu JH, Shen F. STK33 promotes hepatocellular carcinoma through binding to c-Myc. Gut 2016; 65:124-33. [PMID: 25398772 PMCID: PMC4717356 DOI: 10.1136/gutjnl-2014-307545] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 10/29/2014] [Indexed: 01/28/2023]
Abstract
OBJECTIVE STK33 has been reported to play an important role in cancer cell proliferation. We investigated the role of STK33 in hepatocellular carcinoma (HCC) and its underlying mechanisms. DESIGN 251 patients with HCC were analysed for association between STK33 expression and clinical stage and survival rate. Tamoxifen (TAM)-inducible, hepatocyte-specific STK33 transgenic and knockout mice models were used to study the role of STK33 in liver tumorigenesis. HCC cell lines were used to study the role of STK33 in cell proliferation in vitro and in vivo. RESULTS STK33 expression was found to be frequently upregulated in patients with HCC. Significant associations were found between increased expression of STK33 and advanced HCC staging and shorter disease-free survival of patients. Overexpression of STK33 increased HCC cell proliferation both in vitro and in vivo, whereas suppression of STK33 inhibited this effect. Using a TAM-inducible, hepatocyte-specific STK33 transgenic mouse model, we found that overexpression of STK33 resulted in increased hepatocyte proliferation, leading to tumour cell burst. Using a TAM-inducible, hepatocyte-specific STK33 knockout mouse model, we found that, when subjected to the diethylnitrosamine (DEN) liver cancer bioassay, STK33KO(flox/flox, Alb-ERT2-Cre) mice exhibited a markedly lower incidence of tumour formation compared with control mice. The underlying mechanism may be that STK33 binds directly to c-Myc and increases its transcriptional activity. In particular, the C-terminus of STK33 blocks STK33/c-Myc association, downregulates HCC cell proliferation, and reduces DEN-induced liver tumour cell number and tumour size. CONCLUSIONS STK33 plays an essential role in hepatocellular proliferation and liver tumorigenesis. The C-terminus of STK33 could be a potential therapeutic target in the treatment of patients with STK33-overexpressed HCC.
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Affiliation(s)
- Tian Yang
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Bin Song
- The 3rd Department of General Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Jin Zhang
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Guang-Shun Yang
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Han Zhang
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Wei-Feng Yu
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Meng-Chao Wu
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Jun-Hua Lu
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
| | - Feng Shen
- Department of Hepatic Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai, China
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16
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Myc and its interactors take shape. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:469-83. [PMID: 24933113 DOI: 10.1016/j.bbagrm.2014.06.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 06/03/2014] [Accepted: 06/04/2014] [Indexed: 12/11/2022]
Abstract
The Myc oncoprotein is a key contributor to the development of many human cancers. As such, understanding its molecular activities and biological functions has been a field of active research since its discovery more than three decades ago. Genome-wide studies have revealed Myc to be a global regulator of gene expression. The identification of its DNA-binding partner protein, Max, launched an area of extensive research into both the protein-protein interactions and protein structure of Myc. In this review, we highlight key insights with respect to Myc interactors and protein structure that contribute to the understanding of Myc's roles in transcriptional regulation and cancer. Structural analyses of Myc show many critical regions with transient structures that mediate protein interactions and biological functions. Interactors, such as Max, TRRAP, and PTEF-b, provide mechanistic insight into Myc's transcriptional activities, while others, such as ubiquitin ligases, regulate the Myc protein itself. It is appreciated that Myc possesses a large interactome, yet the functional relevance of many interactors remains unknown. Here, we discuss future research trends that embrace advances in genome-wide and proteome-wide approaches to systematically elucidate mechanisms of Myc action. This article is part of a Special Issue entitled: Myc proteins in cell biology and pathology.
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17
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Pin1 regulates the dynamics of c-Myc DNA binding to facilitate target gene regulation and oncogenesis. Mol Cell Biol 2013; 33:2930-49. [PMID: 23716601 DOI: 10.1128/mcb.01455-12] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The Myc oncoprotein is considered a master regulator of gene transcription by virtue of its ability to modulate the expression of a large percentage of all genes. However, mechanisms that direct Myc's recruitment to DNA and target gene selection to elicit specific cellular functions have not been well elucidated. Here, we report that the Pin1 prolyl isomerase enhances recruitment of serine 62-phosphorylated Myc and its coactivators to select promoters during gene activation, followed by promoting Myc's release associated with its degradation. This facilitates Myc's activation of genes involved in cell growth and metabolism, resulting in enhanced proproliferative activity, even while controlling Myc levels. In cancer cells with impaired Myc degradation, Pin1 still enhances Myc DNA binding, although it no longer facilitates Myc degradation. Thus, we find that Pin1 and Myc are cooverexpressed in cancer, and this drives a gene expression pattern that we show is enriched in poor-outcome breast cancer subtypes. This study provides new insight into mechanisms regulating Myc DNA binding and oncogenic activity, it reveals a novel role for Pin1 in the regulation of transcription factors, and it elucidates a mechanism that can contribute to oncogenic cooperation between Pin1 and Myc.
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18
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Dang CV. MYC on the path to cancer. Cell 2012; 149:22-35. [PMID: 22464321 DOI: 10.1016/j.cell.2012.03.003] [Citation(s) in RCA: 2313] [Impact Index Per Article: 192.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Revised: 01/30/2012] [Accepted: 03/07/2012] [Indexed: 11/30/2022]
Abstract
The MYC oncogene contributes to the genesis of many human cancers. Recent insights into its expression and function have led to therapeutic opportunities. MYC's activation by bromodomain proteins could be inhibited by drug-like molecules, resulting in tumor inhibition in vivo. Tumor growth can also be curbed by pharmacologically uncoupling bioenergetic pathways involving glucose or glutamine metabolism from Myc-induced cellular biomass accumulation. Other approaches to halt Myc on the path to cancer involve targeting Myc-Max dimerization or Myc-induced microRNA expression. Here the richness of our understanding of MYC is reviewed, highlighting new biological insights and opportunities for cancer therapies.
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Affiliation(s)
- Chi V Dang
- Division of Hematology-Oncology, Department of Medicine, Abramson Cancer Center, Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Andresen C, Helander S, Lemak A, Farès C, Csizmok V, Carlsson J, Penn LZ, Forman-Kay JD, Arrowsmith CH, Lundström P, Sunnerhagen M. Transient structure and dynamics in the disordered c-Myc transactivation domain affect Bin1 binding. Nucleic Acids Res 2012; 40:6353-66. [PMID: 22457068 PMCID: PMC3401448 DOI: 10.1093/nar/gks263] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The crucial role of Myc as an oncoprotein and as a key regulator of cell growth makes it essential to understand the molecular basis of Myc function. The N-terminal region of c-Myc coordinates a wealth of protein interactions involved in transformation, differentiation and apoptosis. We have characterized in detail the intrinsically disordered properties of Myc-1–88, where hierarchical phosphorylation of S62 and T58 regulates activation and destruction of the Myc protein. By nuclear magnetic resonance (NMR) chemical shift analysis, relaxation measurements and NOE analysis, we show that although Myc occupies a very heterogeneous conformational space, we find transiently structured regions in residues 22–33 and in the Myc homology box I (MBI; residues 45–65); both these regions are conserved in other members of the Myc family. Binding of Bin1 to Myc-1–88 as assayed by NMR and surface plasmon resonance (SPR) revealed primary binding to the S62 region in a dynamically disordered and multivalent complex, accompanied by population shifts leading to altered intramolecular conformational dynamics. These findings expand the increasingly recognized concept of intrinsically disordered regions mediating transient interactions to Myc, a key transcriptional regulator of major medical importance, and have important implications for further understanding its multifaceted role in gene regulation.
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Affiliation(s)
- Cecilia Andresen
- Division of Molecular Biotechnology, Department of Physics, Chemistry and Biology, Linköping University, SE-58183 Linköping, Sweden
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Effective formation of the segregation-competent complex determines successful partitioning of the bovine papillomavirus genome during cell division. J Virol 2010; 84:11175-88. [PMID: 20810736 DOI: 10.1128/jvi.01366-10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Effective segregation of the bovine papillomavirus type 1 (BPV1), Epstein-Barr virus (EBV), and Kaposi's sarcoma-associated human herpesvirus type 8 (KSHV) genomes into daughter cells is mediated by a single viral protein that tethers viral genomes to host mitotic chromosomes. The linker proteins that mediate BPV1, EBV, and KSHV segregation are E2, LANA1, and EBNA1, respectively. The N-terminal transactivation domain of BPV1 E2 is responsible for chromatin attachment and subsequent viral genome segregation. Because E2 transcriptional activation and chromatin attachment functions are not mutually exclusive, we aimed to determine the requirement of these activities during segregation by analyzing chimeric E2 proteins. This approach allowed us to separate the two activities. Our data showed that attachment of the segregation protein to chromatin is not sufficient for proper segregation. Rather, formation of a segregation-competent complex which carries multiple copies of the segregation protein is required. Complementation studies of E2 functional domains indicated that chromatin attachment and transactivation functions must act in concert to ensure proper plasmid segregation. These data indicate that there are specific interactions between linker molecules and transcription factors/complexes that greatly increase segregation-competent complex formation. We also showed, using hybrid E2 molecules, that restored segregation function does not involve interactions with Brd4.
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Miller M. The importance of being flexible: the case of basic region leucine zipper transcriptional regulators. Curr Protein Pept Sci 2009; 10:244-69. [PMID: 19519454 DOI: 10.2174/138920309788452164] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Large volumes of protein sequence and structure data acquired by proteomic studies led to the development of computational bioinformatic techniques that made possible the functional annotation and structural characterization of proteins based on their primary structure. It has become evident from genome-wide analyses that many proteins in eukaryotic cells are either completely disordered or contain long unstructured regions that are crucial for their biological functions. The content of disorder increases with evolution indicating a possibly important role of disorder in the regulation of cellular systems. Transcription factors are no exception and several proteins of this class have recently been characterized as premolten/molten globules. Yet, mammalian cells rely on these proteins to control expression of their 30,000 or so genes. Basic region:leucine zipper (bZIP) DNA-binding proteins constitute a major class of eukaryotic transcriptional regulators. This review discusses how conformational flexibility "built" into the amino acid sequence allows bZIP proteins to interact with a large number of diverse molecular partners and to accomplish their manifold cellular tasks in a strictly regulated and coordinated manner.
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Affiliation(s)
- Maria Miller
- Macromolecular Crystallography Laboratory, National Cancer Institute at Frederick, Frederick, MD 21702-1201, USA.
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22
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Lascu I. Nm23-H1/NDP kinase folding intermediates and cancer: a hypothesis. J Bioenerg Biomembr 2006; 38:265-8. [PMID: 16944300 DOI: 10.1007/s10863-006-9042-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Accepted: 04/07/2006] [Indexed: 11/28/2022]
Abstract
The Nm23-H1/nucleoside diphosphate (NDP) kinase A is a metastasis suppressor, besides its enzymatic activity. The mutant S120G has been found in high-grade neuroblastomas. The mutant protein, once denatured in urea, is unable to refold in vitro. A size-exclusion chromatography analysis of the folding/association pathway showed that recombinant wild-type and S120G mutant human Nm23-H1/NDP kinase A unfold and refold passing through a molten globule state while typical hexameric NDP kinases unfold without dissociated species and refold through a native monomeric intermediate. A survey of the recent literature showed that several proteins involved in cancer, and their mutants, are marginally stable, like the wild-type Nm23-H1/NDP kinase A, or are misfolded, like its S120G mutant. We therefore suggest that the low thermodynamic stability and the folding intermediate of the Nm23-H1/NDP kinase A may be necessary for its regulatory properties.
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Affiliation(s)
- Ioan Lascu
- Institut de Biochimie et Génétique Cellulaires, UMR 5095 University Victor Segalen Bordeaux2 and CNRS, 1, rue Camille Saint-Saëns, 33077, Bordeaux Cedex, France.
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Abstract
The Myc family proteins are potent oncogenes that can activate and repress a very large number of cellular target genes. The amino terminus of Myc contains a transactivation domain that can recruit a number of nuclear cofactors with diverse activities. Functional studies link transactivation to the ability of Myc to promote normal cell proliferation and for oncogenic transformation. The biochemical mechanism of Myc-mediated transactivation has revealed a wide range of effects on chromatin and basal transcription. This review summarizes recent advances in understanding the function of Myc as a transcriptional activator and the role of this activity in Myc biological activities.
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Affiliation(s)
- Victoria H Cowling
- Department of Pharmacology, Dartmouth Medical School, One Medical Center Drive, Lebanon, NH 03756, USA
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Pattanaik S, Xie CH, Kong Q, Shen KA, Yuan L. Directed evolution of plant basic helix-loop-helix transcription factors for the improvement of transactivational properties. BIOCHIMICA ET BIOPHYSICA ACTA 2006; 1759:308-18. [PMID: 16837081 DOI: 10.1016/j.bbaexp.2006.04.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Revised: 04/09/2006] [Accepted: 04/21/2006] [Indexed: 11/18/2022]
Abstract
Myc-RP from Perilla frutescens and Delila from Antirrhinum majus, two plant basic helix-loop-helix transcription factors (bHLH TFs) involved in the flavonoid biosynthetic pathway, have been used for the improvement of transactivational properties by directed evolution. Through two rounds of DNA shuffling, Myc-RP variants with up to 70-fold increase in transcriptional activities have been identified using a yeast transactivation system. In a tobacco protoplast transient expression assay, one of the most improved variants, M2-1, also shows significant increase of transactivation. The majority of resulting mutations (approximately 53%) are localized in the acidic (activation) domains of the improved Myc-RP variants. In variant M2-1, three of the four mutations (L301P/N354D/S401F) are in the acidic domain. The fourth mutation (K157M) is localized to a helix within the N-terminal interaction domain. Combinatorial site-directed mutagenesis reveals that, while the acidic domain mutations contribute modestly to the increase in activity, the K157M substitution is responsible for 80% of the improvement observed in variant M2-1. The transactivation activity of the K157M/N354D double mutant is equal to that of M2-1. These results suggest that the interaction domain plays a critical role in transactivation of these bHLH TFs. Delila variants have also been screened for increased activities toward the Arabidopsis chalcone synthase (CHS) promoter, a pathway promoter that responds weakly to the bHLH TFs. Variants with increased activity on the CHS promoter, while maintaining wildtype-level activities on the naturally responsive dihydroflavonol reductase promoter, have been obtained. This study demonstrates that functional properties of TFs can be modified by directed evolution.
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Affiliation(s)
- Sitakanta Pattanaik
- Department of Plant and Soil Sciences, University of Kentucky, Cooper and University Drives, Lexington, KY 40546, USA
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Minezaki Y, Homma K, Kinjo AR, Nishikawa K. Human transcription factors contain a high fraction of intrinsically disordered regions essential for transcriptional regulation. J Mol Biol 2006; 359:1137-49. [PMID: 16697407 DOI: 10.1016/j.jmb.2006.04.016] [Citation(s) in RCA: 193] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2006] [Revised: 04/04/2006] [Accepted: 04/05/2006] [Indexed: 12/11/2022]
Abstract
Human transcriptional regulation factors, such as activators, repressors, and enhancer-binding factors are quite different from their prokaryotic counterparts in two respects: the average sequence in human is more than twice as long as that in prokaryotes, while the fraction of sequence aligned to domains of known structure is 31% in human transcription factors (TFs), less than half of that in bacterial TFs (72%). Intrinsically disordered (ID) regions were identified by a disorder-prediction program, and were found to be in good agreement with available experimental data. Analysis of 401 human TFs with experimental evidence from the Swiss-Prot database showed that as high as 49% of the entire sequence of human TFs is occupied by ID regions. More than half of the human TFs consist of a small DNA binding domain (DBD) and long ID regions frequently sandwiching unassigned regions. The remaining TFs have structural domains in addition to DBDs and ID regions. Experimental studies, particularly those with NMR, revealed that the transactivation domains in unbound TFs are usually unstructured, but become structured upon binding to their partners. The sequences of human and mouse TF orthologues are 90.5% identical despite a high incidence of ID regions, probably reflecting important functional roles played by ID regions. In general ID regions occupy a high fraction in TFs of eukaryotes, but not in prokaryotes. Implications of this dichotomy are discussed in connection with their functional roles in transcriptional regulation and evolution.
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Affiliation(s)
- Yoshiaki Minezaki
- Laboratory of Gene-Product Informatics, Center For Information Biology & DNA Data Bank of Japan, National Institute of Genetics, Yata 1111, Mishima, Shizuoka 411-8540, Japan
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Abstract
We identified 1113 articles (103 reviews, 1010 primary research articles) published in 2005 that describe experiments performed using commercially available optical biosensors. While this number of publications is impressive, we find that the quality of the biosensor work in these articles is often pretty poor. It is a little disappointing that there appears to be only a small set of researchers who know how to properly perform, analyze, and present biosensor data. To help focus the field, we spotlight work published by 10 research groups that exemplify the quality of data one should expect to see from a biosensor experiment. Also, in an effort to raise awareness of the common problems in the biosensor field, we provide side-by-side examples of good and bad data sets from the 2005 literature.
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Affiliation(s)
- Rebecca L Rich
- Center for Biomolecular Interaction Analysis, University of Utah, Salt Lake City, UT 84132, USA
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Benassayag C, Montero L, Colombié N, Gallant P, Cribbs D, Morello D. Human c-Myc isoforms differentially regulate cell growth and apoptosis in Drosophila melanogaster. Mol Cell Biol 2005; 25:9897-909. [PMID: 16260605 PMCID: PMC1280252 DOI: 10.1128/mcb.25.22.9897-9909.2005] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The human c-myc proto-oncogene, implicated in the control of many cellular processes including cell growth and apoptosis, encodes three isoforms which differ in their N-terminal region. The functions of these isoforms have never been addressed in vivo. Here, we used Drosophila melanogaster to examine their functions in a fully integrated system. First, we established that the human c-Myc protein can rescue lethal mutations of the Drosophila myc ortholog, dmyc, demonstrating the biological relevance of this model. Then, we characterized a new lethal dmyc insertion allele, which permits expression of human c-Myc in place of dMyc and used it to compare physiological activities of these isoforms in whole-organism rescue, transcription, cell growth, and apoptosis. These isoforms differ both quantitatively and qualitatively. Most remarkably, while the small c-MycS form truncated for much of its N-terminal trans-activation domain efficiently rescued viability and cell growth, it did not induce detectable programmed cell death. Our data indicate that the main functional difference between c-Myc isoforms resides in their apoptotic properties and that the N-terminal region, containing the conserved MbI motif, is decisive in governing the choice between growth and death.
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Affiliation(s)
- C Benassayag
- Centre de Biologie du Développement, CNRS UMR 5547, Université Paul Sabatier, 118 Rte. de Narbonne, 31062 Toulouse Cedex, France
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Ponzielli R, Katz S, Barsyte-Lovejoy D, Penn LZ. Cancer therapeutics: targeting the dark side of Myc. Eur J Cancer 2005; 41:2485-501. [PMID: 16243519 DOI: 10.1016/j.ejca.2005.08.017] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The potent Myc oncoprotein plays a pivotal role as a regulator of tumorigenesis in numerous human cancers of diverse origin. Experimental evidence shows that inhibiting Myc significantly halts tumour cell growth and proliferation. This review summarises recent progress in understanding the function of Myc as a transcription factor, with emphasis on key protein interactions and target gene regulation. In addition, major advances in drug development aimed at eliminating Myc are described, including antisense and triple helix forming oligonucleotides, porphyrins and siRNA. Future anti-Myc strategies are also discussed that inhibit Myc at the level of expression and/or function. Targeting the dark side of Myc with novel therapeutic agents promises to have a profound impact in combating cancer.
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Affiliation(s)
- Romina Ponzielli
- Ontario Cancer Institute/Princess Margaret Hospital, Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, Ont., Canada M5G 2M9
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Barrett JF, Lee LA, Dang CV. Stimulation of Myc transactivation by the TATA binding protein in promoter-reporter assays. BMC BIOCHEMISTRY 2005; 6:7. [PMID: 15876353 PMCID: PMC1145180 DOI: 10.1186/1471-2091-6-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Accepted: 05/05/2005] [Indexed: 12/21/2022]
Abstract
Background The c-Myc oncogenic transcription factor heterodimerizes with Max, binds specific DNA sites and regulates transcription. The role of Myc in transcriptional activation involves its binding to TRRAP and histone acetylases; however, Myc's ability to activate transcription in transient transfection assays is remarkably weak (2 to 5 fold) when compared to other transcription factors. Since a deletion Myc mutant D106-143 and a substitution mutant W135E that weakly binds TRRAP are still fully active in transient transfection reporter assays and the TATA binding protein (TBP) has been reported to directly bind Myc, we sought to determine the effect of TBP on Myc transactivation. Results We report here a potent stimulation of Myc transactivation by TBP, allowing up to 35-fold transactivation of reporter constructs. Although promoters with an initiator (InR) element briskly responded to Myc transactivation, the presence of an InR significantly diminished the response to increasing amounts of TBP. We surmise from these findings that promoters containing both TATA and InR elements may control Myc responsive genes that require brisk increased expression within a narrow window of Myc levels, independent of TBP. In contrast, promoters driven by the TATA element only, may also respond to modulation of TBP activity or levels. Conclusion Our observations not only demonstrate that TBP is limiting for Myc transactivation in transient transfection experiments, but they also suggest that the inclusion of TBP in Myc transactivation assays may further improve the characterization of c-Myc target genes.
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Affiliation(s)
- John F Barrett
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Linda A Lee
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Chi V Dang
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
- The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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