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Fagnan A, Aid Z, Baille M, Drakul A, Robert E, Lopez CK, Thirant C, Lecluse Y, Rivière J, Ignacimouttou C, Salmoiraghi S, Anguita E, Naimo A, Marzac C, Pflumio F, Malinge S, Wichmann C, Huang Y, Lobry C, Chaumeil J, Soler E, Bourquin J, Nerlov C, Bernard OA, Schwaller J, Mercher T. The ETO2 transcriptional cofactor maintains acute leukemia by driving a MYB/EP300-dependent stemness program. Hemasphere 2024; 8:e90. [PMID: 38903535 PMCID: PMC11187848 DOI: 10.1002/hem3.90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/13/2024] [Accepted: 05/01/2024] [Indexed: 06/22/2024] Open
Abstract
Transcriptional cofactors of the ETO family are recurrent fusion partners in acute leukemia. We characterized the ETO2 regulome by integrating transcriptomic and chromatin binding analyses in human erythroleukemia xenografts and controlled ETO2 depletion models. We demonstrate that beyond its well-established repressive activity, ETO2 directly activates transcription of MYB, among other genes. The ETO2-activated signature is associated with a poorer prognosis in erythroleukemia but also in other acute myeloid and lymphoid leukemia subtypes. Mechanistically, ETO2 colocalizes with EP300 and MYB at enhancers supporting the existence of an ETO2/MYB feedforward transcription activation loop (e.g., on MYB itself). Both small-molecule and PROTAC-mediated inhibition of EP300 acetyltransferases strongly reduced ETO2 protein, chromatin binding, and ETO2-activated transcripts. Taken together, our data show that ETO2 positively enforces a leukemia maintenance program that is mediated in part by the MYB transcription factor and that relies on acetyltransferase cofactors to stabilize ETO2 scaffolding activity.
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Affiliation(s)
- Alexandre Fagnan
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
- MRC Molecular Hematology Unit, MRC Weatherall Institute of Molecular Medicine, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Zakia Aid
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Marie Baille
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Aneta Drakul
- Division of Oncology and Children's Research CentreUniversity Children's Hospital ZurichZurichSwitzerland
| | - Elie Robert
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Cécile K. Lopez
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Cécile Thirant
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Yann Lecluse
- Gustave Roussy, Plateforme Imagerie et Cytométrie, Université Paris‐Saclay, UMS AMMICA, INSERM US23, CNRS UMS 3655VillejuifFrance
| | - Julie Rivière
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Cathy Ignacimouttou
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
| | - Silvia Salmoiraghi
- Department of Oncology and HematologyAzienda Socio Sanitaria Territoriale Papa Giovanni XXIII, FROM Research Foundation, Papa Giovanni XXIII HospitalBergamoItaly
| | - Eduardo Anguita
- Hematology Department, Hospital Clínico San Carlos (HCSC), IML, IdISSC, Department of MedicineUniversidad Complutense de Madrid (UCM)MadridSpain
| | - Audrey Naimo
- Gustave Roussy, Genomic PlatformUniversité Paris‐Saclay, UMS AMMICA, INSERM US23, CNRS UMS 3655VillejuifFrance
| | - Christophe Marzac
- Department of HematologyLeukemia Interception Program, Personalized Cancer Prevention Center, Gustave RoussyVillejuifFrance
| | - Françoise Pflumio
- Equipe Labellisée Ligue Contre le CancerParisFrance
- Unité de Recherche (UMR)‐E008 Stabilité Génétique, Cellules Souches et Radiations, Team Niche and Cancer in Hematopoiesis, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA)Université de Paris‐Université Paris‐SaclayFontenay‐aux‐RosesFrance
- OPALE Carnot Institute, The Organization for Partnerships in LeukemiaParisFrance
| | - Sébastien Malinge
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Telethon Kids Institute, Perth Children's HospitalNedlandsAustralia
| | - Christian Wichmann
- Department of Transfusion Medicine, Cell Therapeutics and HaemostasisLudwig‐Maximilians‐University of MunichMunichGermany
| | - Yun Huang
- Division of Oncology and Children's Research CentreUniversity Children's Hospital ZurichZurichSwitzerland
| | - Camille Lobry
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- INSERM U944, CNRS UMR7212Institut de Recherche Saint Louis and Université de ParisParisFrance
| | - Julie Chaumeil
- Université de Paris, Institut Cochin, INSERM, CNRSParisFrance
| | - Eric Soler
- IGMM, University of Montpellier, CNRS, Montpellier, France & Université de Paris, Laboratory of Excellence GR‐ExParisFrance
| | - Jean‐Pierre Bourquin
- Division of Oncology and Children's Research CentreUniversity Children's Hospital ZurichZurichSwitzerland
| | - Claus Nerlov
- MRC Molecular Hematology Unit, MRC Weatherall Institute of Molecular Medicine, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | | | - Juerg Schwaller
- Department of BiomedicineUniversity Children's Hospital Beider Basel (UKBB), University of BaselBaselSwitzerland
| | - Thomas Mercher
- Gustave Roussy, INSERM U1170Université Paris‐SaclayVillejuifFrance
- Equipe Labellisée Ligue Contre le CancerParisFrance
- OPALE Carnot Institute, The Organization for Partnerships in LeukemiaParisFrance
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Huang J, Fehr A, Jäwert F, Nilsson JA, Morris LGT, Stenman G, Andersson MK. MYB alternative promoter activity is increased in adenoid cystic carcinoma metastases and is associated with a specific gene expression signature. Oral Oncol 2024; 151:106763. [PMID: 38493544 DOI: 10.1016/j.oraloncology.2024.106763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/21/2024] [Accepted: 03/12/2024] [Indexed: 03/19/2024]
Abstract
OBJECTIVE Adenoid cystic carcinoma (ACC) is a head and neck cancer with a poor long-term prognosis that shows frequent local recurrences and distant metastases. The tumors are characterized by MYB oncogene activation and are notoriously unresponsive to systemic therapies. The biological underpinnings behind therapy resistance of disseminated ACC are largely unknown. Here, we have studied the molecular and clinical significance of MYB alternative promoter (TSS2) usage in ACC metastases. MATERIALS AND METHODS MYB TSS2 activity was investigated in primary tumors and metastases from 26 ACC patients using RNA-sequencing and quantitative real-time PCR analysis. Differences in global gene expression between MYB TSS2 high and low cases were studied, and pathway analyses were performed. RESULTS MYB TSS2 activity was significantly higher in ACC metastases than in primary tumors (median activity 15.1 vs 3.0, P = 0.0003). MYB TSS2 high ACC metastases showed a specific gene expression signature, including increased expression of multi-drug resistance genes and canonical MYB target genes, and suppression of the p53 and NOTCH pathways. CONCLUSIONS Collectively, our findings indicate that elevated MYB TSS2 activity is associated with metastases, potential drug resistance, and augmented MYB-driven gene expression in ACC. Our study advocates the need for new therapies that specifically target MYB and drug resistance mechanisms in disseminated ACC.
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Affiliation(s)
- Junchi Huang
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - André Fehr
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - Fredrik Jäwert
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - Jonas A Nilsson
- Harry Perkins Institute of Medical Research, University of Western Australia, Perth, Australia; Sahlgrenska Center for Cancer Research, Department of Surgery, Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Luc G T Morris
- Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Göran Stenman
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - Mattias K Andersson
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden.
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3
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Halblander FN, Meng FW, Murphy PJ. Anp32e protects against accumulation of H2A.Z at Sox motif containing promoters during zebrafish gastrulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.572196. [PMID: 38187710 PMCID: PMC10769258 DOI: 10.1101/2023.12.18.572196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Epigenetic regulation of chromatin states is crucial for proper gene expression programs and progression during development, but precise mechanisms by which epigenetic factors influence differentiation remain poorly understood. Here we find that the histone variant H2A.Z accumulates at Sox motif-containing promoters during zebrafish gastrulation while neighboring genes become transcriptionally active. These changes coincide with reduced expression of anp32e, the H2A.Z histone removal chaperone, suggesting that loss of Anp32e may lead to increases in H2A.Z during differentiation. Remarkably, genetic removal of Anp32e in embryos leads to H2A.Z accumulation prior to gastrulation, and precocious developmental transcription of Sox motif associated genes. Altogether, our results provide compelling evidence for a mechanism in which Anp32e restricts H2A.Z accumulation at Sox motif-containing promoters, and subsequent down-regulation of Anp32e enables temporal up-regulation of Sox motif associated genes.
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Affiliation(s)
- Fabian N. Halblander
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester NY, 14642, USA
| | - Fanju W. Meng
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester NY, 14642, USA
| | - Patrick J. Murphy
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester NY, 14642, USA
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Fehr A, Arvidsson G, Nordlund J, Lönnerholm G, Stenman G, Andersson MK. Increased MYB alternative promoter usage is associated with relapse in acute lymphoblastic leukemia. Genes Chromosomes Cancer 2023; 62:597-606. [PMID: 37218648 DOI: 10.1002/gcc.23151] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 05/09/2023] [Accepted: 05/09/2023] [Indexed: 05/24/2023] Open
Abstract
Therapy-resistant disease is a major cause of death in patients with acute lymphoblastic leukemia (ALL). Activation of the MYB oncogene is associated with ALL and leads to uncontrolled neoplastic cell proliferation and blocked differentiation. Here, we used RNA-seq to study the clinical significance of MYB expression and MYB alternative promoter (TSS2) usage in 133 pediatric ALLs. RNA-seq revealed that all cases analyzed overexpressed MYB and demonstrated MYB TSS2 activity. qPCR analyses confirmed the expression of the alternative MYB promoter also in seven ALL cell lines. Notably, high MYB TSS2 activity was significantly associated with relapse (p = 0.007). Moreover, cases with high MYB TSS2 usage showed evidence of therapy-resistant disease with increased expression of ABC multidrug resistance transporter genes (e.g., ABCA2, ABCB5, and ABCC10) and enzymes catalyzing drug degradation (e.g., CYP1A2, CYP2C9, and CYP3A5). Elevated MYB TSS2 activity was further associated with augmented KRAS signaling (p < 0.05) and decreased methylation of the conventional MYB promoter (p < 0.01). Taken together, our results suggest that MYB alternative promoter usage is a novel potential prognostic biomarker for relapse and therapy resistance in pediatric ALL.
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Affiliation(s)
- André Fehr
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - Gustav Arvidsson
- Department of Medical Sciences and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Jessica Nordlund
- Department of Medical Sciences and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Gudmar Lönnerholm
- Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden
| | - Göran Stenman
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - Mattias K Andersson
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
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5
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Weng J, Yang S, Shen J, Liu H, Xu Y, Hao D, Wang S. Molecular dynamics simulation reveals DNA-specific recognition mechanism via c-Myb in pseudo-palindromic consensus of mim-1 promoter. J Zhejiang Univ Sci B 2023; 24:883-895. [PMID: 37752090 PMCID: PMC10522569 DOI: 10.1631/jzus.b2200634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/07/2023] [Indexed: 09/28/2023]
Abstract
This study aims to gain insight into the DNA-specific recognition mechanism of c-Myb transcription factor during the regulation of cell early differentiation and proliferation. Therefore, we chose the chicken myeloid gene, mitochondrial import protein 1 (mim-1), as a target to study the binding specificity between potential dual-Myb-binding sites. The c-Myb-binding site in mim-1 is a pseudo-palindromic sequence AACGGTT, which contains two AACNG consensuses. Simulation studies in different biological scenarios revealed that c-Myb binding with mim-1 in the forward strand (complex F) ismore stable than that inthereverse strand (complex R). The principal component analysis (PCA) dynamics trajectory analyses suggested an opening motion of the recognition helices of R2 and R3 (R2R3), resulting in the dissociation of DNA from c-Myb in complex R at 330 K, triggered by the reduced electrostatic potential on the surface of R2R3. Furthermore, the DNA confirmation and hydrogen-bond interaction analyses indicated that the major groove width of DNA increased in complex R, which affected on the hydrogen-bond formation ability between R2R3 and DNA, and directly resulted in the dissociation of DNA from R2R3. The steered molecular dynamics (SMD) simulation studies also suggested that the electrostatic potential, major groove width, and hydrogen bonds made major contribution to the DNA-specific recognition. In vitro trials confirmed the simulation results that c-Myb specifically bound to mim-1 in the forward strand. This study indicates that the three-dimensional (3D) structure features play an important role in the DNA-specific recognition mechanism by c-Myb besides the AACNG consensuses, which is beneficial to understanding the cell early differentiation and proliferation regulated by c-Myb, as well as the prediction of novel c-Myb-binding motifs in tumorigenesis.
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Affiliation(s)
- Jinru Weng
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou 310000, China
| | - Shuo Yang
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun 130021, China
| | - Jinkang Shen
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou 310000, China
| | - Hongsen Liu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou 310000, China
| | - Yuzi Xu
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou 310000, China
| | - Dongyun Hao
- Institute of Agricultural Biotechnology, Jilin Academy of Agricultural Sciences (JAAS), Changchun 130033, China.
| | - Shan Wang
- Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Hangzhou 310000, China.
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6
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Lemma RB, Ledsaak M, Fuglerud BM, Rodríguez-Castañeda F, Eskeland R, Gabrielsen OS. MYB regulates the SUMO protease SENP1 and its novel interaction partner UXT, modulating MYB target genes and the SUMO landscape. J Biol Chem 2023; 299:105062. [PMID: 37468105 PMCID: PMC10463205 DOI: 10.1016/j.jbc.2023.105062] [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: 11/18/2022] [Revised: 07/05/2023] [Accepted: 07/07/2023] [Indexed: 07/21/2023] Open
Abstract
SUMOylation is a post-translational modification frequently found on nuclear proteins, including transcription factors (TFs) and coactivators. By controlling the activity of several TFs, SUMOylation may have far-reaching effects. MYB is an example of a developmental TF subjected to SUMO-mediated regulation, through both SUMO conjugation and SUMO binding. How SUMO affects MYB target genes is unknown. Here, we explored the global effect of reduced SUMOylation of MYB on its downstream gene programs. RNA-Seq in K562 cells after MYB knockdown and rescue with mutants having an altered SUMO status revealed a number of differentially regulated genes and distinct gene ontology term enrichments. Clearly, the SUMO status of MYB both quantitatively and qualitatively affects its regulome. The transcriptome data further revealed that MYB upregulates the SUMO protease SENP1, a key enzyme that removes SUMO conjugation from SUMOylated proteins. Given this role of SENP1 in the MYB regulome, we expanded the analysis, mapped interaction partners of SENP1, and identified UXT as a novel player affecting the SUMO system by acting as a repressor of SENP1. MYB inhibits the expression of UXT suggesting that MYB is able not only to control a specific gene program directly but also indirectly by affecting the SUMO landscape through SENP1 and UXT. These findings suggest an autoactivation loop whereby MYB, through enhancing SENP1 and reducing UXT, is itself being activated by a reduced level of repressive SUMOylation. We propose that overexpressed MYB, seen in multiple cancers, may drive this autoactivation loop and contribute to oncogenic activation of MYB.
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Affiliation(s)
- Roza Berhanu Lemma
- Department of Biosciences, University of Oslo, Oslo, Norway; Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway.
| | - Marit Ledsaak
- Department of Biosciences, University of Oslo, Oslo, Norway; Faculty of Medicine, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | | | | | - Ragnhild Eskeland
- Department of Biosciences, University of Oslo, Oslo, Norway; Faculty of Medicine, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Faculty of Medicine, Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
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7
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Clarke ML, Lemma RB, Walton DS, Volpe G, Noyvert B, Gabrielsen OS, Frampton J. MYB insufficiency disrupts proteostasis in hematopoietic stem cells, leading to age-related neoplasia. Blood 2023; 141:1858-1870. [PMID: 36603185 PMCID: PMC10646772 DOI: 10.1182/blood.2022019138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 01/07/2023] Open
Abstract
MYB plays a key role in gene regulation throughout the hematopoietic hierarchy and is critical for the maintenance of normal hematopoietic stem cells (HSC). Acquired genetic dysregulation of MYB is involved in the etiology of a number of leukemias, although inherited noncoding variants of the MYB gene are a susceptibility factor for many hematological conditions, including myeloproliferative neoplasms (MPN). The mechanisms that connect variations in MYB levels to disease predisposition, especially concerning age dependency in disease initiation, are completely unknown. Here, we describe a model of Myb insufficiency in mice that leads to MPN, myelodysplasia, and leukemia in later life, mirroring the age profile of equivalent human diseases. We show that this age dependency is intrinsic to HSC, involving a combination of an initial defective cellular state resulting from small effects on the expression of multiple genes and a progressive accumulation of further subtle changes. Similar to previous studies showing the importance of proteostasis in HSC maintenance, we observed altered proteasomal activity and elevated proliferation indicators, followed by elevated ribosome activity in young Myb-insufficient mice. We propose that these alterations combine to cause an imbalance in proteostasis, potentially creating a cellular milieu favoring disease initiation.
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Affiliation(s)
- Mary L. Clarke
- Institute of Cancer & Genomic Sciences, College of Medical & Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Roza B. Lemma
- Department of Biosciences, University of Oslo, Oslo, Norway
- Centre for Molecular Medicine Norway, Nordic EMBL Partnership, University of Oslo, Oslo, Norway
| | - David S. Walton
- Institute of Cancer & Genomic Sciences, College of Medical & Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Giacomo Volpe
- Institute of Cancer & Genomic Sciences, College of Medical & Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Boris Noyvert
- Institute of Cancer & Genomic Sciences, College of Medical & Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- CRUK Birmingham Centre and Centre for Computational Biology, University of Birmingham, Birmingham, United Kingdom
| | | | - Jon Frampton
- Institute of Cancer & Genomic Sciences, College of Medical & Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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8
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Tejera Nevado P, Tešan Tomić T, Atefyekta A, Fehr A, Stenman G, Andersson MK. Synthetic oleanane triterpenoids suppress MYB oncogene activity and sensitize T-cell acute lymphoblastic leukemia cells to chemotherapy. Front Oncol 2023; 13:1126354. [PMID: 37077825 PMCID: PMC10106619 DOI: 10.3389/fonc.2023.1126354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 03/24/2023] [Indexed: 04/05/2023] Open
Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy with poor prognosis. The MYB oncogene encodes a master transcription factor that is activated in the majority of human T-ALLs. In the present study, we have performed a large-scale screening with small-molecule drugs to find clinically useful inhibitors of MYB gene expression in T-ALL. We identified several pharmacological agents that potentially could be used to treat MYB-driven malignancies. In particular, treatment with the synthetic oleanane triterpenoids (OTs) bardoxolone methyl and omaveloxolone decreased MYB gene activity and expression of MYB downstream target genes in T-ALL cells with constitutive MYB gene activation. Notably, treatment with bardoxolone methyl and omaveloxolone led to a dose-dependent reduction in cell viability and induction of apoptosis at low nanomolar concentrations. In contrast, normal bone marrow-derived cells were unaffected at these concentrations. Bardoxolone methyl and omaveloxolone treatment downregulated the expression of DNA repair genes and sensitized T-ALL cells to doxorubicin, a drug that is part of the standard therapy of T-ALL. OT treatment may thus potentiate DNA-damaging chemotherapy through attenuation of DNA repair. Taken together, our results indicate that synthetic OTs may be useful in the treatment of T-ALL and potentially also in other MYB-driven malignancies.
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9
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Wu YL, Pan LH, Yi ZJ, Zhang WF, Gong JP. c-Myb Dominates TBK1-Mediated Endotoxin Tolerance in Kupffer Cells by Negatively Regulating DTX4. J Immunol Res 2023; 2023:5990156. [PMID: 37032653 PMCID: PMC10081914 DOI: 10.1155/2023/5990156] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 01/11/2023] [Accepted: 02/14/2023] [Indexed: 04/03/2023] Open
Abstract
As a protective mechanism regulating excessive inflammation, endotoxin tolerance plays a vital role in regulating endotoxin shock. Kupffer cells are players in mediating endotoxin tolerance. Nonetheless, the regulatory mechanism regulating endotoxin tolerance is barely known. A nonclassical IKK kinase called TRAF-associated NF-κB activator (TANK)-binding kinase 1 (TBK1) can regulate inflammation. Here, we found that TBK1 is required for endotoxin tolerance in Kupffer cells. TBK1 plays a dominant role in regulating endotoxin tolerance by negatively regulating the induction of p100 processing. Deltex E3 ubiquitin ligase 4 (DTX4), a negative regulator of TBK1, can promote TBK1 K48-mediated ubiquitination and indirectly regulate endotoxin tolerance in Kupffer cells. We demonstrate that the c-Myb transcription factor could negatively regulate DTX4. Overexpression of c-Myb can be used to reduce the ubiquitination of TBK1 by reducing DTX4 transcription and to boost the anti-inflammatory effect of endotoxin tolerance. Thus, this study reveals a novel theory of TBK1-mediated endotoxin tolerance in Kupffer cells.
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Affiliation(s)
- Yi-Lin Wu
- Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China
| | - Le-Han Pan
- Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China
| | - Zhu-Jun Yi
- Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China
- Department of Hepatobiliary Surgery, Chongqing University Three Gorges Hospital, Chongqing 404100, China
| | - Wen-Feng Zhang
- Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China
| | - Jian-Ping Gong
- Department of Hepatobiliary Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China
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10
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Song H, Liu Y, Tan Y, Zhang Y, Jin W, Chen L, Wu S, Yan J, Li J, Chen Z, Chen S, Wang K. Recurrent noncoding somatic and germline WT1 variants converge to disrupt MYB binding in acute promyelocytic leukemia. Blood 2022; 140:1132-1144. [PMID: 35653587 PMCID: PMC9461475 DOI: 10.1182/blood.2021014945] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 05/24/2022] [Indexed: 11/22/2022] Open
Abstract
Genetic alternations can occur at noncoding regions, but how they contribute to cancer pathogenesis is poorly understood. Here, we established a mutational landscape of cis-regulatory regions (CREs) in acute promyelocytic leukemia (APL) based on whole-genome sequencing analysis of paired tumor and germline samples from 24 patients and epigenetic profiling of 16 patients. Mutations occurring in CREs occur preferentially in active enhancers bound by the complex of master transcription factors in APL. Among significantly enriched mutated CREs, we found a recurrently mutated region located within the third intron of WT1, an essential regulator of normal and malignant hematopoiesis. Focusing on noncoding mutations within this WT1 intron, an analysis on 169 APL patients revealed that somatic mutations were clustered into a focal hotspot region, including one site identified as a germline polymorphism contributing to APL risk. Significantly decreased WT1 expression was observed in APL patients bearing somatic and/or germline noncoding WT1 variants. Furthermore, biallelic WT1 inactivation was recurrently found in APL patients with noncoding WT1 variants, which resulted in the complete loss of WT1. The high incidence of biallelic inactivation suggested the tumor suppressor activity of WT1 in APL. Mechanistically, noncoding WT1 variants disrupted MYB binding on chromatin and suppressed the enhancer activity and WT1 expression through destroying the chromatin looping formation. Our study highlights the important role of noncoding variants in the leukemogenesis of APL.
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Affiliation(s)
- Huan Song
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yabin Liu
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yun Tan
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi Zhang
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wen Jin
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Sino-French Research Center for Life Sciences and Genomics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; and
| | - Li Chen
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shishuang Wu
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jinsong Yan
- Department of Hematology, the Second Hospital of Dalian Medical University, Dalian, China
| | - Junmin Li
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhu Chen
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Saijuan Chen
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Kankan Wang
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- Sino-French Research Center for Life Sciences and Genomics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; and
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11
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Fuglerud BM, Drissler S, Lotto J, Stephan TL, Thakur A, Cullum R, Hoodless PA. SOX9 reprograms endothelial cells by altering the chromatin landscape. Nucleic Acids Res 2022; 50:8547-8565. [PMID: 35904801 PMCID: PMC9410909 DOI: 10.1093/nar/gkac652] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 06/15/2022] [Accepted: 07/20/2022] [Indexed: 01/08/2023] Open
Abstract
The transcription factor SOX9 is activated at the onset of endothelial-to-mesenchymal transition (EndMT) during embryonic development and in pathological conditions. Its roles in regulating these processes, however, are not clear. Using human umbilical vein endothelial cells (HUVECs) as an EndMT model, we show that SOX9 expression alone is sufficient to activate mesenchymal genes and steer endothelial cells towards a mesenchymal fate. By genome-wide mapping of the chromatin landscape, we show that SOX9 displays features of a pioneer transcription factor, such as opening of chromatin and leading to deposition of active histone modifications at silent chromatin regions, guided by SOX dimer motifs and H2A.Z enrichment. We further observe highly transient and dynamic SOX9 binding, possibly promoted through its eviction by histone phosphorylation. However, while SOX9 binding is dynamic, changes in the chromatin landscape and cell fate induced by SOX9 are persistent. Finally, our analysis of single-cell chromatin accessibility indicates that SOX9 opens chromatin to drive EndMT in atherosclerotic lesions in vivo. This study provides new insight into key molecular functions of SOX9 and mechanisms of EndMT and highlights the crucial developmental role of SOX9 and relevance to human disease.
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Affiliation(s)
- Bettina M Fuglerud
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6H 3N1, Canada.,Department of Biosciences, University of Oslo, 0316 Oslo, Norway
| | - Sibyl Drissler
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada.,Cell and Developmental Biology Program, University of British Columbia V6T 1Z3, Vancouver, British Columbia, Canada
| | - Jeremy Lotto
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada.,Cell and Developmental Biology Program, University of British Columbia V6T 1Z3, Vancouver, British Columbia, Canada
| | - Tabea L Stephan
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada.,Cell and Developmental Biology Program, University of British Columbia V6T 1Z3, Vancouver, British Columbia, Canada
| | - Avinash Thakur
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6H 3N1, Canada
| | - Rebecca Cullum
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada
| | - Pamela A Hoodless
- Terry Fox Laboratory, BC Cancer, Vancouver, British Columbia V5Z 1L3, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6H 3N1, Canada.,Cell and Developmental Biology Program, University of British Columbia V6T 1Z3, Vancouver, British Columbia, Canada.,School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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12
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Lemma RB, Fleischer T, Martinsen E, Ledsaak M, Kristensen V, Eskeland R, Gabrielsen OS, Mathelier A. Pioneer transcription factors are associated with the modulation of DNA methylation patterns across cancers. Epigenetics Chromatin 2022; 15:13. [PMID: 35440061 PMCID: PMC9016969 DOI: 10.1186/s13072-022-00444-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/14/2022] [Indexed: 12/15/2022] Open
Abstract
Methylation of cytosines on DNA is a prominent modification associated with gene expression regulation. Aberrant DNA methylation patterns have recurrently been linked to dysregulation of the regulatory program in cancer cells. To shed light on the underlying molecular mechanism driving this process, we hypothesised that aberrant methylation patterns could be controlled by the binding of specific transcription factors (TFs) across cancer types. By combining DNA methylation arrays and gene expression data with TF binding sites (TFBSs), we explored the interplay between TF binding and DNA methylation in 19 cancer types. We performed emQTL (expression–methylation quantitative trait loci) analyses independently in each cancer type and identified 13 TFs whose expression levels are correlated with local DNA methylation patterns around their binding sites in at least 2 cancer types. The 13 TFs are mainly associated with local demethylation and are enriched for pioneer function, suggesting a specific role for these TFs in modulating chromatin structure and transcription in cancer patients. Furthermore, we confirmed that de novo methylation is precluded across cancers at CpGs lying in genomic regions enriched for TF binding signatures associated with SP1, CTCF, NRF1, GABPA, KLF9, and/or YY1. The modulation of DNA methylation associated with TF binding was observed at cis-regulatory regions controlling immune- and cancer-associated pathways, corroborating that the emQTL signals were derived from both cancer and tumor-infiltrating cells. As a case example, we experimentally confirmed that FOXA1 knock-down is associated with higher methylation in regions bound by FOXA1 in breast cancer MCF-7 cells. Finally, we reported physical interactions between FOXA1 with TET1 and TET2 both in an in vitro setup and in vivo at physiological levels in MCF-7 cells, adding further support for FOXA1 attracting TET1 and TET2 to induce local demethylation in cancer cells.
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Affiliation(s)
- Roza Berhanu Lemma
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway
| | - Thomas Fleischer
- Department of Cancer Genetics, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Emily Martinsen
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway.,Institute of Basic Medical Sciences, Department of Molecular Medicine, and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Marit Ledsaak
- Institute of Basic Medical Sciences, Department of Molecular Medicine, and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Vessela Kristensen
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Ragnhild Eskeland
- Institute of Basic Medical Sciences, Department of Molecular Medicine, and Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | | | - Anthony Mathelier
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway. .,Department of Medical Genetics, Oslo University Hospital, Oslo, Norway.
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13
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Boontanrart MY, Schröder MS, Stehli GM, Banović M, Wyman SK, Lew RJ, Bordi M, Gowen BG, DeWitt MA, Corn JE. ATF4 Regulates MYB to Increase γ-Globin in Response to Loss of β-Globin. Cell Rep 2021; 32:107993. [PMID: 32755585 DOI: 10.1016/j.celrep.2020.107993] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 05/20/2020] [Accepted: 07/14/2020] [Indexed: 12/26/2022] Open
Abstract
β-Hemoglobinopathies can trigger rapid production of red blood cells in a process known as stress erythropoiesis. Cellular stress prompts differentiating erythroid precursors to express high levels of fetal γ-globin. However, the mechanisms underlying γ-globin production during cellular stress are still poorly defined. Here, we use CRISPR-Cas genome editing to model the stress caused by reduced levels of adult β-globin. We find that decreased β-globin is sufficient to induce robust re-expression of γ-globin, and RNA sequencing (RNA-seq) of differentiating isogenic erythroid precursors implicates ATF4 as a causal regulator of this response. ATF4 binds within the HBS1L-MYB intergenic enhancer and regulates expression of MYB, a known γ-globin regulator. Overall, the reduction of ATF4 upon β-globin knockout decreases the levels of MYB and BCL11A. Identification of ATF4 as a key regulator of globin compensation adds mechanistic insight to the poorly understood phenomenon of stress-induced globin compensation and could inform strategies to treat hemoglobinopathies.
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Affiliation(s)
- Mandy Y Boontanrart
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | | | | | - Marija Banović
- Department of Biology, ETH Zurich, Zurich 8092, Switzerland
| | - Stacia K Wyman
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Rachel J Lew
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Matteo Bordi
- Department of Biology, ETH Zurich, Zurich 8092, Switzerland
| | - Benjamin G Gowen
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Mark A DeWitt
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Jacob E Corn
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Biology, ETH Zurich, Zurich 8092, Switzerland; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
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14
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Lemma RB, Ledsaak M, Fuglerud BM, Sandve GK, Eskeland R, Gabrielsen OS. Chromatin occupancy and target genes of the haematopoietic master transcription factor MYB. Sci Rep 2021; 11:9008. [PMID: 33903675 PMCID: PMC8076236 DOI: 10.1038/s41598-021-88516-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 04/13/2021] [Indexed: 02/02/2023] Open
Abstract
The transcription factor MYB is a master regulator in haematopoietic progenitor cells and a pioneer factor affecting differentiation and proliferation of these cells. Leukaemic transformation may be promoted by high MYB levels. Despite much accumulated molecular knowledge of MYB, we still lack a comprehensive understanding of its target genes and its chromatin action. In the present work, we performed a ChIP-seq analysis of MYB in K562 cells accompanied by detailed bioinformatics analyses. We found that MYB occupies both promoters and enhancers. Five clusters (C1-C5) were found when we classified MYB peaks according to epigenetic profiles. C1 was enriched for promoters and C2 dominated by enhancers. C2-linked genes were connected to hematopoietic specific functions and had GATA factor motifs as second in frequency. C1 had in addition to MYB-motifs a significant frequency of ETS-related motifs. Combining ChIP-seq data with RNA-seq data allowed us to identify direct MYB target genes. We also compared ChIP-seq data with digital genomic footprinting. MYB is occupying nearly a third of the super-enhancers in K562. Finally, we concluded that MYB cooperates with a subset of the other highly expressed TFs in this cell line, as expected for a master regulator.
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Affiliation(s)
- Roza B Lemma
- Department of Biosciences, University of Oslo, Blindern, PO Box 1066, 0316, Oslo, Norway
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, 0318, Oslo, Norway
| | - Marit Ledsaak
- Department of Biosciences, University of Oslo, Blindern, PO Box 1066, 0316, Oslo, Norway
- Institute of Basic Medical Sciences, Department of Molecular Medicine, University of Oslo, Blindern, PO Box 1112, 0317, Oslo, Norway
| | - Bettina M Fuglerud
- Department of Biosciences, University of Oslo, Blindern, PO Box 1066, 0316, Oslo, Norway
- Terry Fox Laboratory, BC Cancer, Vancouver, BC, V5Z 1L3, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Geir Kjetil Sandve
- Department of Informatics, University of Oslo, Blindern, PO Box 1080, 0371, Oslo, Norway
| | - Ragnhild Eskeland
- Department of Biosciences, University of Oslo, Blindern, PO Box 1066, 0316, Oslo, Norway
- Institute of Basic Medical Sciences, Department of Molecular Medicine, University of Oslo, Blindern, PO Box 1112, 0317, Oslo, Norway
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Odd S Gabrielsen
- Department of Biosciences, University of Oslo, Blindern, PO Box 1066, 0316, Oslo, Norway.
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15
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Regulation of MYB by distal enhancer elements in human myeloid leukemia. Cell Death Dis 2021; 12:223. [PMID: 33637692 PMCID: PMC7910426 DOI: 10.1038/s41419-021-03515-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/06/2021] [Accepted: 02/08/2021] [Indexed: 12/31/2022]
Abstract
MYB plays vital roles in regulating proliferation and differentiation of hematopoietic progenitor cells, dysregulation of MYB has been implicated in the pathogenesis of leukemia. Although the transcription of MYB has been well studied, its detailed underlying regulatory mechanisms still remain elusive. Here, we detected the long-range interaction between the upstream regions, −34k and −88k, and the MYB promoter in K562, U937, and HL-60 cells using circularized chromosome conformation capture (4C) assay, which declined when MYB was downregulated during chemical-induced differentiation. The enrichment of enhancer markers, H3K4me1 and H3K27ac, and enhancer activity at the −34k and −88k regions were confirmed by ChIP-qPCR and luciferase assay respectively. ChIP-qPCR showed the dynamic binding of GATA1, TAL1, and CCAAT/enhancer-binding protein (C/EBPβ) at −34k and −88k during differentiation of K562 cells. Epigenome editing by a CRISPR-Cas9-based method showed that H3K27ac at −34k enhanced TF binding and MYB expression, while DNA methylation inhibited MYB expression. Taken together, our data revealed that enhancer elements at −34k are required for MYB expression, TF binding, and epigenetic modification are closely involved in this process in human myeloid leukemia cells.
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16
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Zhao Y, Zhang X, Song Z, Wei D, Wang H, Chen W, Sun G, Ma W, Chen K. Bibliometric Analysis of ATAC-Seq and Its Use in Cancer Biology via Nucleic Acid Detection. Front Med (Lausanne) 2020; 7:584728. [PMID: 33224964 PMCID: PMC7670091 DOI: 10.3389/fmed.2020.584728] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/24/2020] [Indexed: 12/11/2022] Open
Abstract
Assay for transposase-accessible chromatin using sequencing (ATAC-seq) is associated with significant progress in biological research and has attracted increasing attention. However, the impact of ATAC-seq on cancer biology has not been objectively analyzed. We categorized 440 ATAC-seq publications according to the publication date, type, field, and country. R 3.6.2 was used to analyze the distribution of research fields. VOSviewer was used for country co-authorship and author co-authorship analyses, and GraphPad Prism 8 was used for correlation analyses of the factors that may affect the number of articles published in different countries. We found that ATAC-seq plays roles in carcinogenesis, anticancer immunity, targeted therapy, and metastasis risk predictions and is most frequently used in studies of leukemia among all types of cancer. We found a significantly strong correlation between the top 10 countries in terms of the number of publications and the gross expenditure on research and development (R&D), the number of universities, and the number of researchers. At present, ATAC-seq technology is undergoing a period of rapid development, making it inseparable from the emphasis and investment in scientific research by many countries. Collectively, ATAC-seq has advantages in the study of the cancer mechanisms because it can detect nucleic acids and thus has good application prospects in the field of cancer, especially in leukemia studies. As a country's economic strength increases and the emphasis on scientific research deepens, ATAC-seq will definitely play a more significant role in the field of cancer biology.
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Affiliation(s)
- Yu Zhao
- Department of Hematology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Xianwen Zhang
- School of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Zhenhua Song
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Disease, Department of Treatment Center for Traumatic Injuries, The Third Affiliated Hospital of Southern Medical University (Academy of Orthopedics of Guangdong Province), Guangzhou, China
| | - Danian Wei
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Disease, Department of Treatment Center for Traumatic Injuries, The Third Affiliated Hospital of Southern Medical University (Academy of Orthopedics of Guangdong Province), Guangzhou, China
| | - Hong Wang
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Disease, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China.,Academy of Orthopedics of Guangdong Province, Guangzhou, China
| | - Wei Chen
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Disease, Department of Musculoskeletal Oncology, The Third Affiliated Hospital of Southern Medical University (Academy of Orthopedics of Guangdong Province), Guangzhou, China
| | - Guodong Sun
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Weiying Ma
- Department of Anesthesiology, Sun Yat-sen Memorial Hospital, Guangzhou, China
| | - Kebing Chen
- Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Disease, Department of Spine Surgery, The Third Affiliated Hospital of Southern Medical University (Academy of Orthopedics of Guangdong Province), Guangzhou, China
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17
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Næs G, Storesund JO, Udayakumar P, Ledsaak M, Gabrielsen OS. Dissecting the transactivation domain (tAD) of the transcription factor c-Myb to assess recent models of tAD function. FEBS Open Bio 2020; 10:2329-2342. [PMID: 32937031 PMCID: PMC7609802 DOI: 10.1002/2211-5463.12978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/25/2020] [Accepted: 09/10/2020] [Indexed: 11/29/2022] Open
Abstract
Transcription factors use a DNA-binding domain to localize their action and a transactivation domain (tAD) to stimulate activation of the associated gene. Recent work has renewed interest in how tADs activate genes, which remains poorly understood. Key features in the new models are exposure of short linear motifs (SLMs) and liquid-liquid phase separation (LLPS). Inspired by the new models for tAD function, we decided to revisit the tAD of the haematopoietic transcription factor c-Myb by performing a mutational analysis to see how these new models fit and potentially explain the tAD behaviour of this master regulator. We know that c-Myb has an acidic tAD, which contains a well-characterized SLM in the form of a LxxLL motif. By testing 12 alanine-scanning mutants and three mutants with major reorganization of its tAD in two mammalian reporter systems, we found a pattern of effects very close to what would be expected from the SLM-exposure model, with strong effects exerted by both acidic replacements and SLM mutation. When the same mutants were tested in a yeast system, the pattern of effects was dramatically different, with the SLM mutation exerting no effect, and tAD behaviour was much less affected by small alterations, as would be expected from a LLPS model. These observations are discussed in the light of the two new tAD models, and a two-step hypothesis for transactivation, combining both models, is proposed.
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Affiliation(s)
- Guro Næs
- Department of BiosciencesUniversity of OsloNorway
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18
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Werwein E, Biyanee A, Klempnauer KH. Intramolecular interaction of B-MYB is regulated through Ser-577 phosphorylation. FEBS Lett 2020; 594:4266-4279. [PMID: 32979888 DOI: 10.1002/1873-3468.13940] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/11/2020] [Accepted: 09/08/2020] [Indexed: 02/02/2023]
Abstract
The transcription factor B-MYB is an important regulator of cell cycle-related processes that is activated by step-wise phosphorylation of multiple sites by cyclin-dependent kinases (CDKs) and conformational changes induced by the peptidylprolyl cis/trans isomerase Pin1. Here, we show that a conserved amino acid sequence around Ser-577 in the C-terminal part of B-MYB is able to interact with the B-MYB DNA-binding domain. Phosphorylation of Ser-577 disrupts this interaction and is regulated by the interplay of CDKs and the phosphatase CDC14B. Deletion of sequences surrounding Ser-577 hyperactivates the transactivation potential of B-MYB, decreases its proteolytic stability, and causes cell cycle defects. Overall, we show for the first time that B-MYB can undergo an intramolecular interaction that is controlled by the phosphorylation state of Ser-577.
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Affiliation(s)
- Eugen Werwein
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Abhiruchi Biyanee
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
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19
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c-Myb regulates tumorigenic potential of embryonal rhabdomyosarcoma cells. Sci Rep 2019; 9:6342. [PMID: 31004084 PMCID: PMC6474878 DOI: 10.1038/s41598-019-42684-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 04/04/2019] [Indexed: 02/08/2023] Open
Abstract
Rhabdomyosarcomas (RMS) are a heterogeneous group of mesodermal tumors, the most common sub-types are embryonal (eRMS) and alveolar (aRMS) rhabdomyosarcoma. Immunohistochemical analysis revealed c-Myb expression in both eRMS and aRMS. c-Myb has been reported to be often associated with malignant human cancers. We therefore investigated the c-Myb role in RMS using cellular models of RMS. Specific suppression of c-Myb by a lentiviral vector expressing doxycycline (Dox)-inducible c-Myb shRNA inhibited proliferation, colony formation, and migration of the eRMS cell line (RD), but not of the aRMS cell line (RH30). Upon c-Myb knockdown in eRMS cells, cells accumulated in G0/G1 phase, the invasive behaviour of cells was repressed, and elevated levels of myosin heavy chain, marker of muscle differentiation, was detected. Next, we used an RD-based xenograft model to investigate the role of c-Myb in eRMS tumorigenesis in vivo. We found that Dox administration did not result in efficient suppression of c-Myb in growing tumors. However, when c-Myb-deficient RD cells were implanted into SCID mice, we observed inefficient tumor grafting and attenuation of tumor growth during the initial stages of tumor expansion. The presented study suggests that c-Myb could be a therapeutic target in embryonal rhabdomyosarcoma assuming that its expression is ablated.
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20
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Thanjeem Begum ME, Baul HS, Venkatesh K, Sen D. Novel miRNA expression in the delta opioid signaling pathway mediated cell survivability in an in vitro model of ER stress. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2019; 17:150-187. [PMID: 30716419 DOI: 10.1016/j.nano.2019.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/21/2018] [Accepted: 01/11/2019] [Indexed: 10/27/2022]
Abstract
Micro RNAs (miRNAs) are small non-coding RNAs which bind to the 3'-untranslated region of a mature mRNA to induce degradation; thereby regulating gene expression. It is reported that dysregulated miRNAs involved in neurodegenerative diseases including Parkinson's disease, could play a significant role as prognostic markers and therapeutic targets. Neuroprotective effect of delta opioid receptors (DOR) and its known miRNA regulation against endoplasmic reticulum (ER) stress have been reported previously by our lab. Current study focuses on understanding the regulation of novel miRNAs by DOR under ER stress. Novel miRNAs were identified for three different samples; control, tunicamycin (ER stress inducer), and tunicamycin+DADLE (DOR agonist). Differentially regulated miRNAs between the different samples were identified and pathway/target genes analysis was carried out. The results suggest that following DOR activation novel miRNAs like xxx-m0073-3p, xxx-m0225-3p, xxx-m0088-3p, xxx-m0098-5p etc. could regulate cell survival mechanisms in neuronal cells (SH-SY5Y) under ER stress.
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Affiliation(s)
- M Erfath Thanjeem Begum
- Cellular and Molecular Therapeutics Laboratory, Centre for Biomaterials, Cellular and Molecular Theranostics, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Himadri Shekhaar Baul
- Cellular and Molecular Therapeutics Laboratory, Centre for Biomaterials, Cellular and Molecular Theranostics, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Katari Venkatesh
- Cellular and Molecular Therapeutics Laboratory, Centre for Biomaterials, Cellular and Molecular Theranostics, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Dwaipayan Sen
- Cellular and Molecular Therapeutics Laboratory, Centre for Biomaterials, Cellular and Molecular Theranostics, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India..
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21
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Weaver TM, Liu J, Connelly KE, Coble C, Varzavand K, Dykhuizen EC, Musselman CA. The EZH2 SANT1 domain is a histone reader providing sensitivity to the modification state of the H4 tail. Sci Rep 2019; 9:987. [PMID: 30700785 PMCID: PMC6353875 DOI: 10.1038/s41598-018-37699-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 12/12/2018] [Indexed: 01/09/2023] Open
Abstract
SANT domains are found in a number of chromatin regulators. They contain approximately 50 amino acids and have high similarity to the DNA binding domain of Myb related proteins. Though some SANT domains associate with DNA others have been found to bind unmodified histone tails. There are two SANT domains in Enhancer of Zeste 2 (EZH2), the catalytic subunit of the Polycomb Repressive Complex 2 (PRC2), of unknown function. Here we show that the first SANT domain (SANT1) of EZH2 is a histone binding domain with specificity for the histone H4 N-terminal tail. Using NMR spectroscopy, mutagenesis, and molecular modeling we structurally characterize the SANT1 domain and determine the molecular mechanism of binding to the H4 tail. Though not important for histone binding, we find that the adjacent stimulation response motif (SRM) stabilizes SANT1 and transiently samples its active form in solution. Acetylation of H4K16 (H4K16ac) or acetylation or methylation of H4K20 (H4K20ac and H4K20me3) are seen to abrogate binding of SANT1 to H4, which is consistent with these modifications being anti-correlated with H3K27me3 in-vivo. Our results provide significant insight into this important regulatory region of EZH2 and the first characterization of the molecular mechanism of SANT domain histone binding.
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Affiliation(s)
- Tyler M Weaver
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Jiachen Liu
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Katelyn E Connelly
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
| | - Chris Coble
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Katayoun Varzavand
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Emily C Dykhuizen
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
| | - Catherine A Musselman
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA.
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22
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Weaver TM, Morrison EA, Musselman CA. Reading More than Histones: The Prevalence of Nucleic Acid Binding among Reader Domains. Molecules 2018; 23:molecules23102614. [PMID: 30322003 PMCID: PMC6222470 DOI: 10.3390/molecules23102614] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 10/02/2018] [Accepted: 10/07/2018] [Indexed: 01/09/2023] Open
Abstract
The eukaryotic genome is packaged into the cell nucleus in the form of chromatin, a complex of genomic DNA and histone proteins. Chromatin structure regulation is critical for all DNA templated processes and involves, among many things, extensive post-translational modification of the histone proteins. These modifications can be “read out” by histone binding subdomains known as histone reader domains. A large number of reader domains have been identified and found to selectively recognize an array of histone post-translational modifications in order to target, retain, or regulate chromatin-modifying and remodeling complexes at their substrates. Interestingly, an increasing number of these histone reader domains are being identified as also harboring nucleic acid binding activity. In this review, we present a summary of the histone reader domains currently known to bind nucleic acids, with a focus on the molecular mechanisms of binding and the interplay between DNA and histone recognition. Additionally, we highlight the functional implications of nucleic acid binding in chromatin association and regulation. We propose that nucleic acid binding is as functionally important as histone binding, and that a significant portion of the as yet untested reader domains will emerge to have nucleic acid binding capabilities.
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Affiliation(s)
- Tyler M Weaver
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
| | - Emma A Morrison
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
| | - Catherine A Musselman
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
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23
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Rodríguez-Castañeda F, Lemma RB, Cuervo I, Bengtsen M, Moen LM, Ledsaak M, Eskeland R, Gabrielsen OS. The SUMO protease SENP1 and the chromatin remodeler CHD3 interact and jointly affect chromatin accessibility and gene expression. J Biol Chem 2018; 293:15439-15454. [PMID: 30082317 DOI: 10.1074/jbc.ra118.002844] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 07/12/2018] [Indexed: 01/22/2023] Open
Abstract
The small ubiquitin-like modifier (SUMO) post-translationally modifies lysine residues of transcription factors and co-regulators and thereby contributes to an important layer of control of the activities of these transcriptional regulators. Likewise, deSUMOylation of these factors by the sentrin-specific proteases (SENPs) also plays a role in gene regulation, but whether SENPs functionally interact with other regulatory factors that control gene expression is unclear. In the present work, we focused on SENP1, specifically, on its role in activation of gene expression investigated through analysis of the SENP1 interactome, which revealed that SENP1 physically interacts with the chromatin remodeler chromodomain helicase DNA-binding protein 3 (CHD3). Using several additional methods, including GST pulldown and co-immunoprecipitation assays, we validated and mapped this interaction, and using CRISPR-Cas9-generated CHD3- and SENP1-KO cells (in the haploid HAP1 cell line), we investigated whether these two proteins are functionally linked in regulating chromatin remodeling and gene expression. Genome-wide ATAC-Seq analysis of the CHD3- and SENP1-KO cells revealed a large degree of overlap in differential chromatin openness between these two mutant cell lines. Moreover, motif analysis and comparison with ChIP-Seq profiles in K562 cells pointed to an association of CHD3 and SENP1 with CCCTC-binding factor (CTCF) and SUMOylated chromatin-associated factors. Lastly, genome-wide RNA-Seq also indicated that these two proteins co-regulate the expression of several genes. We propose that the functional link between chromatin remodeling by CHD3 and deSUMOylation by SENP1 uncovered here provides another level of control of gene expression.
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Affiliation(s)
| | - Roza Berhanu Lemma
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and
| | - Ignacio Cuervo
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and
| | - Mads Bengtsen
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and
| | - Lisa Marie Moen
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and
| | - Marit Ledsaak
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and
| | - Ragnhild Eskeland
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and.,the Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, University of Oslo, P.O. Box 1112 Blindern, N-0317 Oslo, Norway
| | - Odd Stokke Gabrielsen
- From the Department of Biosciences, University of Oslo, P. O. Box 1066 Blindern, N-0316 Oslo and
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24
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Fuglerud BM, Ledsaak M, Rogne M, Eskeland R, Gabrielsen OS. The pioneer factor activity of c-Myb involves recruitment of p300 and induction of histone acetylation followed by acetylation-induced chromatin dissociation. Epigenetics Chromatin 2018; 11:35. [PMID: 29954426 PMCID: PMC6022509 DOI: 10.1186/s13072-018-0208-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 06/26/2018] [Indexed: 12/17/2022] Open
Abstract
Background The concept of pioneer transcription factors is emerging as an essential part of the epigenetic regulation, taking place during cell development and differentiation. However, the precise molecular mechanism underlying pioneer factor activity remains poorly understood. We recently reported that the transcription factor c-Myb acts as a pioneer factor in haematopoiesis, and a point mutation in its DNA binding domain, D152V, is able to abrogate this function. Results Here, we show that specific histone modifications, including H3K27ac, prevent binding of c-Myb to histone tails, representing a novel effect of histone modifications, namely restricting binding of a pioneer factor to chromatin. Furthermore, we have taken advantage of the pioneer-defect D152V mutant to investigate mechanisms of c-Myb’s pioneer factor activity. We show that c-Myb-dependent transcriptional activation of a gene in inaccessible chromatin relies on c-Myb binding to histones, as well as on c-Myb interacting with the histone acetyltransferase p300. ChIP assays show that both wild type and the D152V mutant of c-Myb bind to a selected target gene at its promoter and enhancer, but only wild-type c-Myb causes opening and activation of the locus. Enhancement of histone acetylation restores activation of the same gene in the absence of c-Myb, suggesting that facilitating histone acetylation is a crucial part of the pioneer factor function of c-Myb. Conclusions We suggest a pioneer factor model in which c-Myb binds to regions of closed chromatin and then recruits histone acetyltransferases. By binding to histones, c-Myb facilitates histone acetylation, acting as a cofactor for p300 at c-Myb bound sites. The resulting H3K27ac leads to chromatin opening and detachment of c-Myb from the acetylated chromatin. We propose that the latter phenomenon, acetylation-induced chromatin dissociation, represents a mechanism for controlling the dynamics of pioneer factor binding to chromatin. Electronic supplementary material The online version of this article (10.1186/s13072-018-0208-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bettina M Fuglerud
- Department of Biosciences, University of Oslo, P.O. Box 1066, 0316, Blindern, Oslo, Norway
| | - Marit Ledsaak
- Department of Biosciences, University of Oslo, P.O. Box 1066, 0316, Blindern, Oslo, Norway
| | - Marie Rogne
- Department of Biosciences, University of Oslo, P.O. Box 1066, 0316, Blindern, Oslo, Norway
| | - Ragnhild Eskeland
- Department of Biosciences, University of Oslo, P.O. Box 1066, 0316, Blindern, Oslo, Norway.,Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, 0379, Norway
| | - Odd S Gabrielsen
- Department of Biosciences, University of Oslo, P.O. Box 1066, 0316, Blindern, Oslo, Norway.
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