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Liu N, Zhang J, Chen W, Ma W, Wu T. The RNA methyltransferase METTL16 enhances cholangiocarcinoma growth through PRDM15-mediated FGFR4 expression. J Exp Clin Cancer Res 2023; 42:263. [PMID: 37817227 PMCID: PMC10566113 DOI: 10.1186/s13046-023-02844-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/29/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND RNA N6-Methyladenosine (m6A) modification is implicated in the progression of human cancers including cholangiocarcinoma (CCA). METTL16 is recently identified as a new RNA methyltransferase responsible for m6A modification, although the role of METTL16 in CCA has not yet been examined. The current study aims to investigate the effect and mechanism of the RNA methyltransferase METTL16 in CCA. METHODS The expression of METTL16 in CCA was examined by analyzing publicly available datasets or by IHC staining on tumor samples. siRNA or CRISPR/Cas9-mediated loss of function studies were performed in vitro and in vivo to investigate the oncogenic role of METTL16 in CCA. MeRIP-Seq was carried out to identify the downstream target of METTL16. ChIP-qPCR, immunoprecipitation, and immunoblots were used to explore the regulation mechanisms for METTL16 expression in CCA. RESULTS We observed that the expression of METTL16 was noticeably increased in human CCA tissues. Depletion of METTL16 significantly inhibited CCA cell proliferation and decreased tumor progression. PRDM15 was identified as a key target of METTL16 in CCA cells. Mechanistically, our data showed that METTL16 regulated PRDM15 protein expression via YTHDF1-dependent translation. Accordingly, we observed that restoration of PRDM15 expression could rescue the deficiency of CCA cell proliferation/colony formation induced by METTL16 depletion. Our subsequent analyses revealed that METTL16-PRDM15 signaling regulated the expression of FGFR4 in CCA cells. Specifically, we observed that PRDM15 protein was associated with the FGFR4 promoter to regulate its expression. Furthermore, we showed that the histone acetyltransferase p300 cooperated with the transcription factor YY1 to regulate METTL16 gene expression via histone H3 lysine 27 (H3K27) acetylation in CCA cells. CONCLUSIONS This study describes a novel METTL16-PRDM15-FGFR4 signaling axis which is crucial for CCA growth and may have important therapeutic implications. We showed that depletion of METTL16 significantly inhibited CCA cell proliferation and decreased tumor progression.
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Affiliation(s)
- Nianli Liu
- Department of Pathology and Laboratory Medicine, Tulane University, 1430 Tulane Avenue, SL-79, New Orleans, LA, 70112, USA
| | - Jinqiang Zhang
- Department of Pathology and Laboratory Medicine, Tulane University, 1430 Tulane Avenue, SL-79, New Orleans, LA, 70112, USA
| | - Weina Chen
- Department of Pathology and Laboratory Medicine, Tulane University, 1430 Tulane Avenue, SL-79, New Orleans, LA, 70112, USA
| | - Wenbo Ma
- Department of Pathology and Laboratory Medicine, Tulane University, 1430 Tulane Avenue, SL-79, New Orleans, LA, 70112, USA
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University, 1430 Tulane Avenue, SL-79, New Orleans, LA, 70112, USA.
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2
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Harada T, Perez MW, Kalfon J, Braes FD, Batley R, Eagle K, Nabet B, Leifer B, Kruell J, Paralkar VR, Stegmaier K, Koehler AN, Orkin SH, Pimkin M. Rapid-kinetics degron benchmarking reveals off-target activities and mixed agonism-antagonism of MYB inhibitors. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.07.536032. [PMID: 37066194 PMCID: PMC10104119 DOI: 10.1101/2023.04.07.536032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Attenuating aberrant transcriptional circuits holds great promise for the treatment of numerous diseases, including cancer. However, development of transcriptional inhibitors is hampered by the lack of a generally accepted functional cellular readout to characterize their target specificity and on-target activity. We benchmarked the direct gene-regulatory signatures of six agents reported as inhibitors of the oncogenic transcription factor MYB against targeted MYB degradation in a nascent transcriptomics assay. The inhibitors demonstrated partial specificity for MYB target genes but displayed significant off-target activity. Unexpectedly, the inhibitors displayed bimodal on-target effects, acting as mixed agonists-antagonists. Our data uncover unforeseen agonist effects of small molecules originally developed as TF inhibitors and argue that rapid-kinetics benchmarking against degron models should be used for functional characterization of transcriptional modulators.
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Affiliation(s)
- Taku Harada
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
| | - Monika W. Perez
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
| | - Jérémie Kalfon
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02142, USA
| | - Flora Dievenich Braes
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
| | - Rashad Batley
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
| | - Kenneth Eagle
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
- Ken Eagle Consulting, Houston, TX, 77494, USA
| | - Behnam Nabet
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109, USA
| | - Becky Leifer
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Jasmin Kruell
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Vikram R. Paralkar
- Division of Hematology/Oncology, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Kimberly Stegmaier
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02142, USA
| | - Angela N. Koehler
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02142, USA
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Stuart H. Orkin
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
- Howard Hughes Medical Institute, Boston, MA, 02215, USA
| | - Maxim Pimkin
- Cancer and Blood Disorders Center, Dana-Farber Cancer Institute and Boston Children’s Hospital, Harvard Medical School, Boston, MA, 02215, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, 02142, USA
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3
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Klempnauer KH. C/EBPβ cooperates with MYB to maintain the oncogenic program of AML cells. Oncotarget 2023; 14:174-177. [PMID: 36913305 PMCID: PMC10010626 DOI: 10.18632/oncotarget.28377] [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: 02/10/2023] [Indexed: 03/13/2023] Open
Abstract
Studies on the role of transcription factor MYB in acute myeloid leukemia (AML) have identified MYB as a key regulator of a transcriptional program for self-renewal of AML cells. Recent work summarized here has now highlighted the CCAAT-box/enhancer binding protein beta (C/EBPβ) as an essential factor and potential therapeutic target that cooperates with MYB and coactivator p300 in the maintenance of the leukemic cells.
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Affiliation(s)
- Karl-Heinz Klempnauer
- Correspondence to:Karl-Heinz Klempnauer, Institute for Biochemistry, Westfälische-Wilhelms-Universität, Muenster D-48149, Germany email
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4
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Köhler LF, Reich S, Yusenko M, Klempnauer KH, Shaikh AH, Ahmed K, Begemann G, Schobert R, Biersack B. A New Naphthopyran Derivative Combines c-Myb Inhibition, Microtubule-Targeting Effects, and Antiangiogenic Properties. ACS Med Chem Lett 2022; 13:1783-1790. [PMID: 36385941 PMCID: PMC9661705 DOI: 10.1021/acsmedchemlett.2c00403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/28/2022] [Indexed: 11/28/2022] Open
Abstract
Based on the promising c-Myb inhibitor 1b, a series of 2-amino-4-aryl-4H-naphtho[1,2-b]pyran-3-carbonitriles (1a, 2a-q, 3a-g) were repurposed or newly synthesized via a three-component reaction of 1-naphthol, and various aryl aldehydes and malononitrile and screened for their c-Myb inhibitory activities. 1b also served as a lead compound for seven new naphthopyran derivatives (3a-f), which were cytotoxic with nanomolar IC50 values, to inhibit the polymerization of tubulin, and to destabilize microtubules in living cells. Especially, the alkyne 3f, originally made for intracellular localization studies using click chemistry, showed an overall high activity in all assays performed. A strong G2/M cell cycle arrest was detected, which resulted in a distinct increase in sub-G1 cells through the induction of effector caspases 3 and 7. Inhibition of angiogenesis was confirmed in vitro and in vivo. In summary, 3f was found to be a pleiotropic compound with high selectivity for cancer cells, combining c-Myb inhibitory, microtubule destabilizing, and antiangiogenic effects.
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Affiliation(s)
- Leonhard
H. F. Köhler
- Organic
Chemistry Laboratory, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Sebastian Reich
- Organic
Chemistry Laboratory, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Maria Yusenko
- Institute
for Biochemistry, Westfälische-Wilhelms-Universität, Wilhelm-Klemm-Strasse 2, 48149 Münster, Germany
| | - Karl-Heinz Klempnauer
- Institute
for Biochemistry, Westfälische-Wilhelms-Universität, Wilhelm-Klemm-Strasse 2, 48149 Münster, Germany
| | - Amin H. Shaikh
- Department
of Chemistry & Post Graduate Research Center, Abeda Inamdar Senior College, Camp, Pune 411001, India
| | - Khursheed Ahmed
- Department
of Chemistry & Post Graduate Research Center, Abeda Inamdar Senior College, Camp, Pune 411001, India
| | - Gerrit Begemann
- Developmental
Biology, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Rainer Schobert
- Organic
Chemistry Laboratory, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Bernhard Biersack
- Organic
Chemistry Laboratory, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
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5
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Sagulkoo P, Chuntakaruk H, Rungrotmongkol T, Suratanee A, Plaimas K. Multi-Level Biological Network Analysis and Drug Repurposing Based on Leukocyte Transcriptomics in Severe COVID-19: In Silico Systems Biology to Precision Medicine. J Pers Med 2022; 12:jpm12071030. [PMID: 35887528 PMCID: PMC9319133 DOI: 10.3390/jpm12071030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/16/2022] [Accepted: 06/20/2022] [Indexed: 01/08/2023] Open
Abstract
The coronavirus disease 2019 (COVID-19) pandemic causes many morbidity and mortality cases. Despite several developed vaccines and antiviral therapies, some patients experience severe conditions that need intensive care units (ICU); therefore, precision medicine is necessary to predict and treat these patients using novel biomarkers and targeted drugs. In this study, we proposed a multi-level biological network analysis framework to identify key genes via protein–protein interaction (PPI) network analysis as well as survival analysis based on differentially expressed genes (DEGs) in leukocyte transcriptomic profiles, discover novel biomarkers using microRNAs (miRNA) from regulatory network analysis, and provide candidate drugs targeting the key genes using drug–gene interaction network and structural analysis. The results show that upregulated DEGs were mainly enriched in cell division, cell cycle, and innate immune signaling pathways. Downregulated DEGs were primarily concentrated in the cellular response to stress, lysosome, glycosaminoglycan catabolic process, and mature B cell differentiation. Regulatory network analysis revealed that hsa-miR-6792-5p, hsa-let-7b-5p, hsa-miR-34a-5p, hsa-miR-92a-3p, and hsa-miR-146a-5p were predicted biomarkers. CDC25A, GUSB, MYBL2, and SDAD1 were identified as key genes in severe COVID-19. In addition, drug repurposing from drug–gene and drug–protein database searching and molecular docking showed that camptothecin and doxorubicin were candidate drugs interacting with the key genes. In conclusion, multi-level systems biology analysis plays an important role in precision medicine by finding novel biomarkers and targeted drugs based on key gene identification.
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Affiliation(s)
- Pakorn Sagulkoo
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand; (P.S.); (H.C.); (T.R.)
- Center of Biomedical Informatics, Department of Family Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Hathaichanok Chuntakaruk
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand; (P.S.); (H.C.); (T.R.)
- Center of Excellence in Biocatalyst and Sustainable Biotechnology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Thanyada Rungrotmongkol
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand; (P.S.); (H.C.); (T.R.)
- Center of Excellence in Biocatalyst and Sustainable Biotechnology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Apichat Suratanee
- Department of Mathematics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok 10800, Thailand;
- Intelligent and Nonlinear Dynamics Innovations Research Center, Science and Technology Research Institute, King Mongkut’s University of Technology North Bangkok, Bangkok 10800, Thailand
| | - Kitiporn Plaimas
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand; (P.S.); (H.C.); (T.R.)
- Advance Virtual and Intelligent Computing (AVIC) Center, Department of Mathematics and Computer Science, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Omics Science and Bioinformatics Center, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
- Correspondence:
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6
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Src-Family Protein Kinase Inhibitors Suppress MYB Activity in a p300-Dependent Manner. Cells 2022; 11:cells11071162. [PMID: 35406726 PMCID: PMC8997952 DOI: 10.3390/cells11071162] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 02/05/2023] Open
Abstract
Recent studies have disclosed transcription factor MYB as a potential drug target for malignancies that are dependent on deregulated MYB function, including acute myeloid leukemia (AML) and adenoid cystic carcinoma (ACC). Although transcription factors are often regarded as undruggable, successful targeting of MYB by low-molecular-weight compounds has recently been demonstrated. In an attempt to repurpose known drugs as novel MYB-inhibitory agents, we have screened libraries of approved drugs and drug-like compounds for molecules with MYB-inhibitory potential. Here, we present initial evidence for the MYB-inhibitory activity of the protein kinase inhibitors bosutinib, PD180970 and PD161570, that we identified in a recent screen. We show that these compounds interfere with the activity of the MYB transactivation domain, apparently by disturbing the ability of MYB to cooperate with the coactivator p300. We show that treatment of the AML cell line HL60 with these compounds triggers the up-regulation of the myeloid differentiation marker CD11b and induces cell death. Importantly, we show that these effects are significantly dampened by forced expression of an activated version of MYB, confirming that the ability to suppress MYB function is a relevant activity of these compounds. Overall, our work identifies several protein kinase inhibitors as novel MYB-inhibitory agents and suggests that the inhibition of MYB function may play a role in their pharmacological impact on leukemic cells.
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7
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Schmidt TJ, Klempnauer KH. Natural Products with Antitumor Potential Targeting the MYB-C/EBPβ-p300 Transcription Module. Molecules 2022; 27:molecules27072077. [PMID: 35408476 PMCID: PMC9000602 DOI: 10.3390/molecules27072077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 12/15/2022] Open
Abstract
The transcription factor MYB is expressed predominantly in hematopoietic progenitor cells, where it plays an essential role in the development of most lineages of the hematopoietic system. In the myeloid lineage, MYB is known to cooperate with members of the CCAAT box/enhancer binding protein (C/EBP) family of transcription factors. MYB and C/EBPs interact with the co-activator p300 or its paralog CREB-binding protein (CBP), to form a transcriptional module involved in myeloid-specific gene expression. Recent work has demonstrated that MYB is involved in the development of human leukemia, especially in acute T-cell leukemia (T-ALL) and acute myeloid leukemia (AML). Chemical entities that inhibit the transcriptional activity of the MYB-C/EBPβ-p300 transcription module may therefore be of use as potential anti-tumour drugs. In searching for small molecule inhibitors, studies from our group over the last 10 years have identified natural products belonging to different structural classes, including various sesquiterpene lactones, a steroid lactone, quinone methide triterpenes and naphthoquinones that interfere with the activity of this transcriptional module in different ways. This review gives a comprehensive overview on the various classes of inhibitors and the inhibitory mechanisms by which they affect the MYB-C/EBPβ-p300 transcriptional module as a potential anti-tumor target. We also focus on the current knowledge on structure-activity relationships underlying these biological effects and on the potential of these compounds for further development.
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Affiliation(s)
- Thomas J. Schmidt
- Institute of Pharmaceutical Biology and Phytochemistry (IPBP), University of Münster, PharmaCampus-Corrensstraße 48, D-48149 Munster, Germany
- Correspondence: (T.J.S.); (K.-H.K.)
| | - Karl-Heinz Klempnauer
- Institute of Biochemistry, University of Münster, Corrensstraße 36, D-48149 Munster, Germany
- Correspondence: (T.J.S.); (K.-H.K.)
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8
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Klempnauer KH. C/EBPβ sustains the oncogenic program of AML cells by cooperating with MYB and co-activator p300 in a transcriptional module. Exp Hematol 2022; 108:8-15. [PMID: 35032593 DOI: 10.1016/j.exphem.2022.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/02/2022] [Accepted: 01/07/2022] [Indexed: 11/17/2022]
Abstract
Transcription factor MYB is a key regulator of gene expression in hematopoietic cells and has emerged as a novel drug target for acute myeloid leukemia (AML). Studies aiming to identify potential MYB inhibitors have shown that the natural compound helenalin acetate (HA) inhibits viability and induces cell death and differentiation of AML cells by disrupting the MYB-induced gene expression program. Interestingly, CCAAT-box/enhancer binding protein beta (C/EBPβ), a transcription factor known to cooperate with MYB and the co-activator p300 in myeloid cells, rather than MYB itself, was identified as the primary target of HA. This supports a model in which MYB, C/EBPβ and p300 form the core of a transcriptional module that is essential for the maintenance of proliferative potential of AML cells, highlighting a novel role of C/EBPβ as a pro-leukemogenic factor.
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Affiliation(s)
- Karl-Heinz Klempnauer
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany.
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9
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Transcription factor c-Myb: novel prognostic factor in osteosarcoma. Clin Exp Metastasis 2022; 39:375-390. [PMID: 34994868 DOI: 10.1007/s10585-021-10145-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/28/2021] [Indexed: 12/21/2022]
Abstract
The transcription factor c-Myb is an oncoprotein promoting cell proliferation and survival when aberrantly activated/expressed, thus contributing to malignant transformation. Overexpression of c-Myb has been found in leukemias, breast, colon and adenoid cystic carcinoma. Recent studies revealed its expression also in osteosarcoma cell lines and suggested its functional importance during bone development. However, the relevance of c-Myb in control of osteosarcoma progression remains unknown. A retrospective clinical study was carried out to assess a relationship between c-Myb expression in archival osteosarcoma tissues and prognosis in a cohort of high-grade osteosarcoma patients. In addition, MYB was depleted in metastatic osteosarcoma cell lines SAOS-2 LM5 and 143B and their growth, chemosensitivity, migration and metastatic activity were determined. Immunohistochemical analysis revealed that high c-Myb expression was significantly associated with poor overall survival in the cohort and metastatic progression in young patients. Increased level of c-Myb was detected in metastatic osteosarcoma cell lines and its depletion suppressed their growth, colony-forming capacity, migration and chemoresistance in vitro in a cell line-dependent manner. MYB knock-out resulted in reduced metastatic activity of both SAOS-2 LM5 and 143B cell lines in immunodeficient mice. Transcriptomic analysis revealed the c-Myb-driven functional programs enriched for genes involved in the regulation of cell growth, stress response, cell adhesion and cell differentiation/morphogenesis. Wnt signaling pathway was identified as c-Myb target in osteosarcoma cells. Taken together, we identified c-Myb as a negative prognostic factor in osteosarcoma and showed its involvement in the regulation of osteosarcoma cell growth, chemosensitivity, migration and metastatic activity.
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Yusenko MV, Klempnauer KH. Characterization of the MYB-inhibitory potential of the Pan-HDAC inhibitor LAQ824. BBA ADVANCES 2022; 2:100034. [PMID: 37082582 PMCID: PMC10074929 DOI: 10.1016/j.bbadva.2021.100034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/23/2021] [Accepted: 12/13/2021] [Indexed: 12/13/2022] Open
Abstract
A large body of work has shown that MYB acts as a master transcription regulator in hematopoietic cells and has pinpointed MYB as a potential drug target for acute myeloid leukemia (AML). Here, we have examined the MYB-inhibitory potential of the HDAC inhibitor LAQ824, which was identified in a screen for novel MYB inhibitors. We show that nanomolar concentrations of LAQ824 and the related HDAC inhibitors vorinostat and panobinostat interfere with MYB function in two ways, by inducing its degradation and inhibiting its activity. Reporter assays show that the inhibition of MYB activity by LAQ824 involves the MYB transactivation domain and the cooperation of MYB with co-activator p300, a key MYB interaction partner and driver of MYB activity. In AML cells, LAQ824-induced degradation of MYB is accompanied by expression of myeloid differentiation markers and apoptotic and necrotic cell death. The ability of LAQ824 to inhibit MYB activity is supported by the observation that down-regulation of direct MYB target genes MYC and GFI1 occurs without apparent decrease of MYB expression already after 2 h of treatment with LAQ824. Furthermore, ectopic expression of an activated version of MYB In HL60 cells counteracts the induction of myeloid differentiation by LAQ824. Overall, our data identify LAQ824 and related HDAC inhibitors as potent MYB-inhibitory agents that exert dual effects on MYB expression and activity in AML cells.
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11
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Identification of a c-MYB-directed therapeutic for acute myeloid leukemia. Leukemia 2022; 36:1541-1549. [PMID: 35368048 PMCID: PMC9162920 DOI: 10.1038/s41375-022-01554-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 03/07/2022] [Accepted: 03/21/2022] [Indexed: 11/27/2022]
Abstract
A significant proportion of patients suffering from acute myeloid leukemia (AML) cannot be cured by conventional chemotherapy, relapsed disease being a common problem. Molecular targeting of essential oncogenic mediators is an attractive approach to improving outcomes for this disease. The hematopoietic transcription factor c-MYB has been revealed as a central component of complexes maintaining aberrant gene expression programs in AML. We have previously screened the Connectivity Map database to identify mebendazole as an anti-AML therapeutic targeting c-MYB. In the present study we demonstrate that another hit from this screen, the steroidal lactone withaferin A (WFA), induces rapid ablation of c-MYB protein and consequent inhibition of c-MYB target gene expression, loss of leukemia cell viability, reduced colony formation and impaired disease progression. Although WFA has been reported to have pleiotropic anti-cancer effects, we demonstrate that its anti-AML activity depends on c-MYB modulation and can be partially reversed by a stabilized c-MYB mutant. c-MYB ablation results from disrupted HSP/HSC70 chaperone protein homeostasis in leukemia cells following induction of proteotoxicity and the unfolded protein response by WFA. The widespread use of WFA in traditional medicines throughout the world indicates that it represents a promising candidate for repurposing into AML therapy.
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12
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Yusenko MV, Biyanee A, Frank D, Köhler LHF, Andersson MK, Khandanpour C, Schobert R, Stenman G, Biersack B, Klempnauer KH. Bcr-TMP, a Novel Nanomolar-Active Compound That Exhibits Both MYB- and Microtubule-Inhibitory Activity. Cancers (Basel) 2021; 14:cancers14010043. [PMID: 35008207 PMCID: PMC8750090 DOI: 10.3390/cancers14010043] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 11/19/2022] Open
Abstract
Simple Summary Recent work has identified the transcription regulator MYB as an interesting therapeutic target for the treatment of certain leukemias and other cancers that are dependent on deregulated MYB activity, such as acute myeloid leukemia (AML) and adenoid cystic carcinoma (ACC). Here we report the identification and characterization of 2-amino-4-(3,4,5-trimethoxyphenyl)-4H-naphtho[1,2-b]pyran-3-carbonitrile (Bcr-TMP), a novel highly active MYB inhibitory compound. We show that nanomolar concentrations of Bcr-TMP are sufficient to down-regulate the expression of MYB target genes and induce both cell-death and differentiation in AML cell lines. Importantly, Bcr-TMP also and exerts stronger anti-proliferative effects on MYB-addicted primary AML cells and patient-derived ACC cells than on their non-oncogenic counterparts. Preliminary work shows that Bcr-TMP acts through p300, a protein interacting with MYB and stimulating its activity. Interestingly, Bcr-TMP has an additional activity as an anti-microtubule agent. Overall, Bcr-TMP is an interesting compound that warrants further research to understand its mechanism of action and its therapeutic potential for MYB-dependent malignancies. Abstract Studies of the role of MYB in human malignancies have highlighted MYB as a potential drug target for acute myeloid leukemia (AML) and adenoid cystic carcinoma (ACC). Here, we present the initial characterization of 2-amino-4-(3,4,5-trimethoxyphenyl)-4H-naphtho[1,2-b]pyran-3-carbonitrile (Bcr-TMP), a nanomolar-active MYB-inhibitory compound identified in a screen for novel MYB inhibitors. Bcr-TMP affects MYB function in a dual manner by inducing its degradation and suppressing its transactivation potential by disrupting its cooperation with co-activator p300. Bcr-TMP also interferes with the p300-dependent stimulation of C/EBPβ, a transcription factor co-operating with MYB in myeloid cells, indicating that Bcr-TMP is a p300-inhibitor. Bcr-TMP reduces the viability of AML cell lines at nanomolar concentrations and induces cell-death and expression of myeloid differentiation markers. It also down-regulates the expression of MYB target genes and exerts stronger anti-proliferative effects on MYB-addicted primary murine AML cells and patient-derived ACC cells than on their non-oncogenic counterparts. Surprisingly, we observed that Bcr-TMP also has microtubule-disrupting activity, pointing to a possible link between MYB-activity and microtubule stability. Overall, Bcr-TMP is a highly potent multifunctional MYB-inhibitory agent that warrants further investigation of its therapeutic potential and mechanism(s) of action.
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Affiliation(s)
- Maria V. Yusenko
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, 48149 Munster, Germany; (M.V.Y.); (A.B.)
| | - Abhiruchi Biyanee
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, 48149 Munster, Germany; (M.V.Y.); (A.B.)
| | - Daria Frank
- Department of Medicine A, Hematology and Oncology, University Hospital, Westfälische-Wilhelms-Universität, 48149 Munster, Germany; (D.F.); (C.K.)
| | - Leonhard H. F. Köhler
- Organic Chemistry Laboratory, Universität Bayreuth, 95440 Bayreuth, Germany; (L.H.F.K.); (R.S.); (B.B.)
| | - Mattias K. Andersson
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, 41345 Gothenburg, Sweden; (M.K.A.); (G.S.)
| | - Cyrus Khandanpour
- Department of Medicine A, Hematology and Oncology, University Hospital, Westfälische-Wilhelms-Universität, 48149 Munster, Germany; (D.F.); (C.K.)
| | - Rainer Schobert
- Organic Chemistry Laboratory, Universität Bayreuth, 95440 Bayreuth, Germany; (L.H.F.K.); (R.S.); (B.B.)
| | - Göran Stenman
- Sahlgrenska Center for Cancer Research, Department of Pathology, University of Gothenburg, 41345 Gothenburg, Sweden; (M.K.A.); (G.S.)
| | - Bernhard Biersack
- Organic Chemistry Laboratory, Universität Bayreuth, 95440 Bayreuth, Germany; (L.H.F.K.); (R.S.); (B.B.)
| | - Karl-Heinz Klempnauer
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, 48149 Munster, Germany; (M.V.Y.); (A.B.)
- Correspondence: ; Tel.: +49-251-8333203; Fax: +49-251-8333206
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13
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Liu W, Lin LC, Wang PJ, Chen YN, Wang SC, Chuang YT, Tsai IH, Yu SY, Chang FR, Cheng YB, Huang LC, Huang MY, Chang HW. Nepenthes Ethyl Acetate Extract Provides Oxidative Stress-Dependent Anti-Leukemia Effects. Antioxidants (Basel) 2021; 10:antiox10091410. [PMID: 34573042 PMCID: PMC8464713 DOI: 10.3390/antiox10091410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/26/2021] [Accepted: 08/30/2021] [Indexed: 12/13/2022] Open
Abstract
Several kinds of solvents have been applied to Nepenthes extractions exhibiting antioxidant and anticancer effects. However, they were rarely investigated for Nepenthes ethyl acetate extract (EANT), especially leukemia cells. The purpose of the present study was to evaluate the antioxidant properties and explore the antiproliferation impact and mechanism of EANT in leukemia cells. Five standard assays demonstrated that EANT exhibits antioxidant capability. In the cell line model, EANT dose-responsively inhibited cell viabilities of three leukemia cell lines (HL-60, K-562, and MOLT-4) based on 24 h MTS assays, which were reverted by pretreating oxidative stress and apoptosis inhibitors (N-acetylcysteine and Z-VAD-FMK). Due to similar sensitivities among the three cell lines, leukemia HL-60 cells were chosen for exploring antiproliferation mechanisms. EANT caused subG1 and G1 cumulations, triggered annexin V-detected apoptosis, activated apoptotic caspase 3/7 activity, and induced poly ADP-ribose polymerase expression. Moreover, reactive oxygen species, mitochondrial superoxide, and mitochondrial membrane depolarization were generated by EANT, which was reverted by N-acetylcysteine. The antioxidant response to oxidative stress showed that EANT upregulated mRNA expressions for nuclear factor erythroid 2-like 2 (NFE2L2), catalase (CAT), thioredoxin (TXN), heme oxygenase 1 (HMOX1), and NAD(P)H quinone dehydrogenase 1 (NQO1) genes. Moreover, these oxidative stresses led to DNA damage (γH2AX and 8-hydroxy-2-deoxyguanosine) and were alleviated by N-acetylcysteine. Taken together, EANT demonstrated oxidative stress-dependent anti-leukemia ability to HL-60 cells associated with apoptosis and DNA damage.
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Affiliation(s)
- Wangta Liu
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Li-Ching Lin
- Department of Radiation Oncology, Chi-Mei Foundation Medical Center, Tainan 71004, Taiwan;
- School of Medicine, Taipei Medical University, Taipei 11031, Taiwan
- Chung Hwa University Medical Technology, Tainan 71703, Taiwan
| | - Pei-Ju Wang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
| | - Yan-Ning Chen
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
| | - Sheng-Chieh Wang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
| | - Ya-Ting Chuang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
| | - I-Hsuan Tsai
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
| | - Szu-Yin Yu
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-Y.Y.); (F.-R.C.)
| | - Fang-Rong Chang
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-Y.Y.); (F.-R.C.)
| | - Yuan-Bin Cheng
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan;
| | - Li-Chen Huang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
| | - Ming-Yii Huang
- Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
- Department of Radiation Oncology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (M.-Y.H.); (H.-W.C.); Tel.: +886-7-312-1101 (ext. 7158) (M.-Y.H.); +886-7-312-1101 (ext. 2691) (H.-W.C.)
| | - Hsueh-Wei Chang
- Chung Hwa University Medical Technology, Tainan 71703, Taiwan
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Science, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (P.-J.W.); (Y.-N.C.); (S.-C.W.); (Y.-T.C.); (I.-H.T.); (L.-C.H.)
- Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (M.-Y.H.); (H.-W.C.); Tel.: +886-7-312-1101 (ext. 7158) (M.-Y.H.); +886-7-312-1101 (ext. 2691) (H.-W.C.)
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14
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Porazzi P, De Dominici M, Salvino J, Calabretta B. Targeting the CDK6 Dependence of Ph+ Acute Lymphoblastic Leukemia. Genes (Basel) 2021; 12:genes12091355. [PMID: 34573335 PMCID: PMC8467343 DOI: 10.3390/genes12091355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 12/13/2022] Open
Abstract
Ph+ ALL is a poor-prognosis leukemia subtype driven by the BCR-ABL1 oncogene, either the p190- or the p210-BCR/ABL isoform in a 70:30 ratio. Tyrosine Kinase inhibitors (TKIs) are the drugs of choice in the therapy of Ph+ ALL. In combination with standard chemotherapy, TKIs have markedly improved the outcome of Ph+ ALL, in particular if this treatment is followed by bone marrow transplantation. However, resistance to TKIs develops with high frequency, causing leukemia relapse that results in <5-year overall survival. Thus, new therapies are needed to address relapsed/TKI-resistant Ph+ ALL. We have shown that expression of cell cycle regulatory kinase CDK6, but not of the highly related CDK4 kinase, is required for the proliferation and survival of Ph+ ALL cells. Comparison of leukemia suppression induced by treatment with the clinically-approved dual CDK4/6 inhibitor palbociclib versus CDK6 silencing revealed that the latter treatment was markedly more effective, probably reflecting inhibition of CDK6 kinase-independent effects. Thus, we developed CDK4/6-targeted proteolysis-targeting chimeras (PROTACs) that preferentially degrade CDK6 over CDK4. One compound termed PROTAC YX-2-107, which degrades CDK6 by recruiting the Cereblon ubiquitin ligase, markedly suppressed leukemia burden in mice injected with de novo or TKI-resistant Ph+ ALL. The effect of PROTAC YX-2-107 was comparable or superior to that of palbociclib. The development of CDK6-selective PROTACs represents an effective strategy to exploit the “CDK6 dependence” of Ph+ ALL cells while sparing a high proportion of normal hematopoietic progenitors that depend on both CDK6 and CDK6 for their survival. In combination with other agents, CDK6-selective PROTACs may be valuable components of chemotherapy-free protocols for the therapy of Ph+ ALL and other CDK6-dependent hematological malignancies.
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Affiliation(s)
- Patrizia Porazzi
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA;
- Correspondence:
| | - Marco De Dominici
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | | | - Bruno Calabretta
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA;
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15
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Yusenko MV, Biyanee A, Andersson MK, Radetzki S, von Kries JP, Stenman G, Klempnauer KH. Proteasome inhibitors suppress MYB oncogenic activity in a p300-dependent manner. Cancer Lett 2021; 520:132-142. [PMID: 34256093 DOI: 10.1016/j.canlet.2021.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/18/2021] [Accepted: 07/06/2021] [Indexed: 01/18/2023]
Abstract
Studies of the role of MYB in human malignancies have highlighted MYB as a potential drug target for acute myeloid leukemia (AML) and adenoid cystic carcinoma (ACC). Although transcription factors are often considered un-druggable, recent work has demonstrated successful targeting of MYB by low molecular weight compounds. This has fueled the notion that inhibition of MYB has potential as a therapeutic approach against MYB-driven malignancies. Here, we have used a MYB reporter cell line to screen a library of FDA-approved drugs for novel MYB inhibitors. We demonstrate that proteasome inhibitors have significant MYB-inhibitory activity, prompting us to characterize the proteasome inhibitor oprozomib in more detail. Oprozomib was shown to interfere with the ability of the co-activator p300 to stimulate MYB activity and to exert anti-proliferative effects on human AML and ACC cells. Overall, our work demonstrated suppression of oncogenic MYB activity as a novel result of proteasome inhibition.
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Affiliation(s)
- Maria V Yusenko
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Abhiruchi Biyanee
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Mattias K Andersson
- Sahlgrenska Cancer Center, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
| | - Silke Radetzki
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Jens P von Kries
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Göran Stenman
- Sahlgrenska Cancer Center, Department of Pathology, University of Gothenburg, Gothenburg, Sweden
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16
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Rana P, Shrama A, Mandal CC. Molecular insights into phytochemicals-driven break function in tumor microenvironment. J Food Biochem 2021; 45:e13824. [PMID: 34219240 DOI: 10.1111/jfbc.13824] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 05/06/2021] [Accepted: 05/31/2021] [Indexed: 12/13/2022]
Abstract
Advanced knowledge about the role of tumor microenvironment (TME) in cancer progression has opened various ways to target the vast signaling pathways for cancer treatment. Failures of the currently used drugs have raised out the need to look for novel drugs which can target various crucial aspects of cancer progression (e.g., angiogenesis, uncontrolled cell division, and metastasis). Phytochemicals behaving as potent anticancer agents shows promise as therapeutics. Various phytochemicals, such as curcumin, Epigallocatechin Gallate (EGCG), resveratrol, plumbagin, genistein, and others, have been identified with modulatory effect on TME. These phytochemicals often target the molecular pathways that reside in the tumor vicinity associated with endothelial cells, cancer-associated fibroblasts, immune cells, mesenchymal stem cells, other cell types, vascular and lymphatic networks, and extracellular matrix which are important for tumor progression and development. Some phytochemicals also target the internal signaling pathways, including STAT3, NF-қB, ERK-1/2, and PI3K/Akt signaling of noncancer cell, residing in the microenvironment, and thus inhibiting the supportive effect from these cells in tumor development. However, much information needs to be acquired before using these phytochemicals in cancer treatment. The primary objective of this review is to provide a better knowledge about the role of TME in cancer progression and development, focusing on the different targets which can be used for therapeutic approach, and then to give a brief account on some known phytochemicals to date, which have shown remarkable TME modulatory effects. PRACTICAL APPLICATIONS: For the use of phytochemicals as therapeutics, it is highly recommended that their precise target should be known; therefore studies should be encouraged such that the effects of these phytochemicals can be evaluated on the individual cellular level like how the phytochemical is targeting the tumor-associated macrophage, or any other cell residing in the tumor microenvironment (TME), and the compound should target a specific component of TME to avoid off target effects.
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Affiliation(s)
- Priyanshi Rana
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Amarjeet Shrama
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
| | - Chandi C Mandal
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, India
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17
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Keyvani-Ghamsari S, Khorsandi K, Rasul A, Zaman MK. Current understanding of epigenetics mechanism as a novel target in reducing cancer stem cells resistance. Clin Epigenetics 2021; 13:120. [PMID: 34051847 PMCID: PMC8164819 DOI: 10.1186/s13148-021-01107-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 05/19/2021] [Indexed: 12/13/2022] Open
Abstract
At present, after extensive studies in the field of cancer, cancer stem cells (CSCs) have been proposed as a major factor in tumor initiation, progression, metastasis, and recurrence. CSCs are a subpopulation of bulk tumors, with stem cell-like properties and tumorigenic capabilities, having the abilities of self-renewal and differentiation, thereby being able to generate heterogeneous lineages of cancer cells and lead to resistance toward anti-tumor treatments. Highly resistant to conventional chemo- and radiotherapy, CSCs have heterogeneity and can migrate to different organs and metastasize. Recent studies have demonstrated that the population of CSCs and the progression of cancer are increased by the deregulation of different epigenetic pathways having effects on gene expression patterns and key pathways connected with cell proliferation and survival. Further, epigenetic modifications (DNA methylation, histone modifications, and RNA methylations) have been revealed to be key drivers in the formation and maintenance of CSCs. Hence, identifying CSCs and targeting epigenetic pathways therein can offer new insights into the treatment of cancer. In the present review, recent studies are addressed in terms of the characteristics of CSCs, the resistance thereof, and the factors influencing the development thereof, with an emphasis on different types of epigenetic changes in genes and main signaling pathways involved therein. Finally, targeted therapy for CSCs by epigenetic drugs is referred to, which is a new approach in overcoming resistance and recurrence of cancer.
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Affiliation(s)
| | - Khatereh Khorsandi
- Department of Photodynamic, Medical Laser Research Center, Yara Institute, ACECR, Tehran, Iran.
| | - Azhar Rasul
- Department of Zoology, Government College University Faisalabad, Faisalabad, 38000, Pakistan
| | - Muhammad Khatir Zaman
- Department of Biotechnology, Abdul Wali Khan University Mardan (AWKUM), Mardan, 23200, Pakistan
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18
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Smeenk L, Ottema S, Mulet-Lazaro R, Ebert A, Havermans M, Arricibita Varea A, Fellner M, Pastoors D, van Herk S, Erpelinck-Verschueren C, Grob T, Hoogenboezem RM, Kavelaars FG, Matson DR, Bresnick EH, Bindels EM, Kentsis A, Zuber J, Delwel R. Selective requirement of MYB for oncogenic hyperactivation of a translocated enhancer in leukemia. Cancer Discov 2021; 11:2868-2883. [PMID: 33980539 DOI: 10.1158/2159-8290.cd-20-1793] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/26/2021] [Accepted: 05/07/2021] [Indexed: 11/16/2022]
Abstract
In acute myeloid leukemia (AML) with inv(3)(q21;q26) or t(3;3)(q21;q26), a translocated GATA2 enhancer drives oncogenic expression of EVI1. We generated an EVI1-GFP AML model and applied an unbiased CRISPR/Cas9 enhancer scan to uncover sequence motifs essential for EVI1 transcription. Using this approach, we pinpointed a single regulatory element in the translocated GATA2 enhancer that is critically required for aberrant EVI1 expression. This element contained a DNA binding motif for the transcription factor MYB which specifically occupied this site at the translocated allele and was dispensable for GATA2 expression. MYB knockout as well as peptidomimetic blockade of CBP/p300-dependent MYB functions resulted in downregulation of EVI1 but not of GATA2. Targeting MYB or mutating its DNA-binding motif within the GATA2 enhancer resulted in myeloid differentiation and cell death, suggesting that interference with MYB-driven EVI1 transcription provides a potential entry point for therapy of inv(3)/t(3;3) AMLs.
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Affiliation(s)
- Leonie Smeenk
- Hematology, Erasmus MC Cancer Institute and Oncode Institute
| | - Sophie Ottema
- Hematology, Erasmus MC Cancer Institute and Oncode Institute
| | | | - Anja Ebert
- Department of Molecular Biology and Genetics, Aarhus University
| | | | | | - Michaela Fellner
- Immunology and Cancer, Research Institute of Molecular Pathology
| | - Dorien Pastoors
- Hematology, Erasmus MC Cancer Institute and Oncode Institute
| | | | | | - Tim Grob
- Hematology, Erasmus MC Cancer Institute
| | | | | | - Daniel R Matson
- Cell and Regenerative Biology, Paul Carbone Comprehensive Cancer Center, University of Wisconsin School of Medicine and Public Health
| | - Emery H Bresnick
- Cell and Regenerative Biology, Paul Carbone Comprehensive Cancer Center, University of Wisconsin School of Medicine and Public Health
| | | | - Alex Kentsis
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center
| | - Johannes Zuber
- Immunology and Cancer, Research Institute of Molecular Pathology
| | - Ruud Delwel
- Hematology, Erasmus MC Cancer Institute and Oncode Institute
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19
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MYB oncoproteins: emerging players and potential therapeutic targets in human cancer. Oncogenesis 2021; 10:19. [PMID: 33637673 PMCID: PMC7910556 DOI: 10.1038/s41389-021-00309-y] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 02/05/2021] [Accepted: 02/10/2021] [Indexed: 01/31/2023] Open
Abstract
MYB transcription factors are highly conserved from plants to vertebrates, indicating that their functions embrace fundamental mechanisms in the biology of cells and organisms. In humans, the MYB gene family is composed of three members: MYB, MYBL1 and MYBL2, encoding the transcription factors MYB, MYBL1, and MYBL2 (also known as c-MYB, A-MYB, and B-MYB), respectively. A truncated version of MYB, the prototype member of the MYB family, was originally identified as the product of the retroviral oncogene v-myb, which causes leukaemia in birds. This led to the hypothesis that aberrant activation of vertebrate MYB could also cause cancer. Despite more than three decades have elapsed since the isolation of v-myb, only recently investigators were able to detect MYB genes rearrangements and mutations, smoking gun evidence of the involvement of MYB family members in human cancer. In this review, we will highlight studies linking the activity of MYB family members to human malignancies and experimental therapeutic interventions tailored for MYB-expressing cancers.
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20
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Yusenko MV, Trentmann A, Casolari DA, Abdel Ghani L, Lenz M, Horn M, Dörner W, Klempnauer S, Mootz HD, Arteaga MF, Mikesch JH, D’Andrea RJ, Gonda TJ, Müller-Tidow C, Schmidt TJ, Klempnauer KH. C/EBPβ is a MYB- and p300-cooperating pro-leukemogenic factor and promising drug target in acute myeloid leukemia. Oncogene 2021; 40:4746-4758. [PMID: 33958723 PMCID: PMC8298201 DOI: 10.1038/s41388-021-01800-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 03/29/2021] [Accepted: 04/14/2021] [Indexed: 02/05/2023]
Abstract
Transcription factor MYB has recently emerged as a promising drug target for the treatment of acute myeloid leukemia (AML). Here, we have characterized a group of natural sesquiterpene lactones (STLs), previously shown to suppress MYB activity, for their potential to decrease AML cell proliferation. Unlike what was initially thought, these compounds inhibit MYB indirectly via its cooperation partner C/EBPβ. C/EBPβ-inhibitory STLs affect the expression of a large number of MYB-regulated genes, suggesting that the cooperation of MYB and C/EBPβ broadly shapes the transcriptional program of AML cells. We show that expression of GFI1, a direct MYB target gene, is controlled cooperatively by MYB, C/EBPβ, and co-activator p300, and is down-regulated by C/EBPβ-inhibitory STLs, exemplifying that they target the activity of composite MYB-C/EBPβ-p300 transcriptional modules. Ectopic expression of GFI1, a zinc-finger protein that is required for the maintenance of hematopoietic stem and progenitor cells, partially abrogated STL-induced myelomonocytic differentiation, implicating GFI1 as a relevant target of C/EBPβ-inhibitory STLs. Overall, our data identify C/EBPβ as a pro-leukemogenic factor in AML and suggest that targeting of C/EBPβ may have therapeutic potential against AML.
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Affiliation(s)
- Maria V. Yusenko
- grid.5949.10000 0001 2172 9288Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Amke Trentmann
- grid.5949.10000 0001 2172 9288Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Debora A. Casolari
- grid.1026.50000 0000 8994 5086Centre for Cancer Biology, SA Pathology and University of South Australia, Adelaide, SA Australia
| | - Luca Abdel Ghani
- grid.5949.10000 0001 2172 9288Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Mairin Lenz
- grid.5949.10000 0001 2172 9288Institute for Pharmaceutical Biology and Phytochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Melanie Horn
- grid.5253.10000 0001 0328 4908Department of Medicine V, Hematology, Oncology, Rheumatology, University Hospital Heidelberg, Heidelberg, Germany
| | - Wolfgang Dörner
- grid.5949.10000 0001 2172 9288Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Stefan Klempnauer
- grid.5570.70000 0004 0490 981XDepartment of Mathematics, Ruhr-Universität, Bochum, Germany
| | - Henning D. Mootz
- grid.5949.10000 0001 2172 9288Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Maria Francisca Arteaga
- grid.16149.3b0000 0004 0551 4246Department of Medicine A, Hematology and Oncology, University Hospital, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Jan-Henrik Mikesch
- grid.16149.3b0000 0004 0551 4246Department of Medicine A, Hematology and Oncology, University Hospital, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Richard J. D’Andrea
- grid.1026.50000 0000 8994 5086Centre for Cancer Biology, SA Pathology and University of South Australia, Adelaide, SA Australia
| | - Thomas J. Gonda
- grid.1026.50000 0000 8994 5086Cancer Research Institute, University of South Australia, Adelaide, SA Australia
| | - Carsten Müller-Tidow
- grid.5253.10000 0001 0328 4908Department of Medicine V, Hematology, Oncology, Rheumatology, University Hospital Heidelberg, Heidelberg, Germany
| | - Thomas J. Schmidt
- grid.5949.10000 0001 2172 9288Institute for Pharmaceutical Biology and Phytochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
| | - Karl-Heinz Klempnauer
- grid.5949.10000 0001 2172 9288Institute for Biochemistry, Westfälische-Wilhelms-Universität, Münster, Germany
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21
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Mitra P. Targeting transcription factors in cancer drug discovery. EXPLORATION OF TARGETED ANTI-TUMOR THERAPY 2020; 1:401-412. [PMID: 36046384 PMCID: PMC9402400 DOI: 10.37349/etat.2020.00025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/29/2020] [Indexed: 12/11/2022] Open
Abstract
Cancer drug discovery is currently dominated by clinical trials or clinical research. Several potential drug candidates have been brought into the pipeline of drug discovery after showing very promising results at the pre-clinical level and are waiting to be tested in human clinical trials. Interestingly, among the potential drug candidates, a few of them have targeted transcription factors highlighting the fundamental undruggable nature of these molecules. However, using advanced technologies, researchers were recently successful in partly unlocking this undruggable nature, which was considered as a ‘grey area’ in the early days of drug discovery, and as a result, several potential candidates have emerged recently. The purpose of the review is to highlight some of the recently reported studies of targeting transcription factors in cancer and their promising outcomes.
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Affiliation(s)
- Partha Mitra
- Institute of Health and Biomedical Innovation, the Queensland University of Technology, Brisbane 4059, Australia
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22
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Chen A, Koehler AN. Transcription Factor Inhibition: Lessons Learned and Emerging Targets. Trends Mol Med 2020; 26:508-518. [PMID: 32359481 DOI: 10.1016/j.molmed.2020.01.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 01/10/2020] [Accepted: 01/21/2020] [Indexed: 12/15/2022]
Abstract
Transcription factors have roles at focal points in signaling pathways, controlling many normal cellular processes, such as cell growth and proliferation, metabolism, apoptosis, immune responses, and differentiation. Their activity is frequently deregulated in disease and targeting this class of proteins is a major focus of interest. However, the structural disorder and lack of binding pockets have made design of small molecules for transcription factors challenging. Here, we review some of the most recent developments for small molecule inhibitors of transcription factors emphasized in James Darnell's vision 17 years ago. We also discuss the progress so far on transcription factors recently nominated by genome-scale loss-of-function screens from the cancer dependency map project.
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Affiliation(s)
- Andrew Chen
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02142, USA
| | - Angela N Koehler
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, Massachusetts, MA 02142, USA.
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23
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Monensin, a novel potent MYB inhibitor, suppresses proliferation of acute myeloid leukemia and adenoid cystic carcinoma cells. Cancer Lett 2020; 479:61-70. [PMID: 32014461 DOI: 10.1016/j.canlet.2020.01.039] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/24/2020] [Accepted: 01/29/2020] [Indexed: 02/06/2023]
Abstract
The master transcriptional regulator MYB is a key oncogenic driver in several human neoplasms, particularly in acute myeloid leukemia (AML) and adenoid cystic carcinoma (ACC). MYB is therefore an attractive target for drug development in MYB-activated malignancies. Here, we employed a MYB-reporter cell line and identified the polyether ionophores monensin, salinomycin, and nigericin as novel inhibitors of MYB activity. As a proof of principle, we show that monensin affects the expression of a significant number of MYB-regulated genes in AML cells and causes down-regulation of MYB expression, loss of cell viability, and induction of differentiation and apoptosis. Furthermore, monensin significantly inhibits proliferation of primary murine AML cells but not of normal hematopoietic progenitors, reflecting a high MYB-dependence of leukemic cells and underscoring the efficacy of monensin in MYB-activated malignancies. Importantly, monensin also suppressed the viability and non-adherent growth of adenoid cystic carcinoma (ACC) cells expressing MYB-NFIB fusion oncoproteins. Our data show that a single compound with significant MYB-inhibitory activity is effective against malignant cells from two distinct MYB-driven human neoplasms. Hence, monensin and related compounds are promising molecular scaffolds for development of novel MYB inhibitors.
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24
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Barrett CM, McCracken R, Elmer J, Haynes KA. Components from the Human c-myb Transcriptional Regulation System Reactivate Epigenetically Repressed Transgenes. Int J Mol Sci 2020; 21:E530. [PMID: 31947658 PMCID: PMC7014047 DOI: 10.3390/ijms21020530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 01/07/2020] [Accepted: 01/07/2020] [Indexed: 11/16/2022] Open
Abstract
A persistent challenge for mammalian cell engineering is the undesirable epigenetic silencing of transgenes. Foreign DNA can be incorporated into closed chromatin before and after it has been integrated into a host cell's genome. To identify elements that mitigate epigenetic silencing, we tested components from the c-myb and NF-kB transcriptional regulation systems in transiently transfected DNA and at chromosomally integrated transgenes in PC-3 and HEK 293 cells. DNA binding sites for MYB (c-myb) placed upstream of a minimal promoter enhanced expression from transiently transfected plasmid DNA. We targeted p65 and MYB fusion proteins to a chromosomal transgene, UAS-Tk-luciferase, that was silenced by ectopic Polycomb chromatin complexes. Transient expression of Gal4-MYB induced an activated state that resisted complete re-silencing. We used custom guide RNAs and dCas9-MYB to target MYB to different positions relative to the promoter and observed that transgene activation within ectopic Polycomb chromatin required proximity of dCas9-MYB to the transcriptional start site. Our report demonstrates the use of MYB in the context of the CRISPR-activation system, showing that DNA elements and fusion proteins derived from c-myb can mitigate epigenetic silencing to improve transgene expression in engineered cell lines.
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Affiliation(s)
- Cassandra M. Barrett
- School of Biological and Health Systems Engineering, Arizona State University, 501 East Tyler Mall, Tempe, AZ 85287, USA;
| | - Reilly McCracken
- Department of Chemical Engineering, Villanova University, 217 White Hall, 800 East Lancaster Avenue, Villanova, PA 19085, USA; (R.M.); (J.E.)
| | - Jacob Elmer
- Department of Chemical Engineering, Villanova University, 217 White Hall, 800 East Lancaster Avenue, Villanova, PA 19085, USA; (R.M.); (J.E.)
| | - Karmella A. Haynes
- School of Biological and Health Systems Engineering, Arizona State University, 501 East Tyler Mall, Tempe, AZ 85287, USA;
- Wallace H. Coulter Department of Biomedical Engineering, Emory University, Atlanta, GA 30322, USA
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25
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Abstract
The c-Myb gene encodes a transcription factor that regulates cell proliferation, differentiation, and apoptosis through protein-protein interaction and transcriptional regulation of signaling pathways. The protein is frequently overexpressed in human leukemias, breast cancers, and other solid tumors suggesting that it is a bona fide oncogene. c-MYB is often overexpressed by translocation in human tumors with t(6;7)(q23;q34) resulting in c-MYB-TCRβ in T cell ALL, t(X;6)(p11;q23) with c-MYB-GATA1 in acute basophilic leukemia, and t(6;9)(q22-23;p23-24) with c-MYB-NF1B in adenoid cystic carcinoma. Antisense oligonucleotides to c-MYB were developed to purge bone marrow cells to eliminate tumor cells in leukemias. Recently, small molecules that inhibit c-MYB activity have been developed to disrupt its interaction with p300. The Dmp1 (cyclin D binding myb-like protein 1; Dmtf1) gene was isolated through its virtue for binding to cyclin D2. It is a transcription factor that has a Myb-like repeat for DNA binding. The Dmtf1 protein directly binds to the Arf promoter for transactivation and physically interacts with p53 to activate the p53 pathway. The gene is hemizygously deleted in 35-42% of human cancers and is associated with longer survival. The significances of aberrant expression of c-MYB and DMTF1 proteins in human cancers and their clinical significances are discussed.
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Affiliation(s)
- Elizabeth A. Fry
- The Department of Pathology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157 USA
| | - Kazushi Inoue
- The Department of Pathology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157 USA
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26
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Emerging Role of Histone Acetyltransferase in Stem Cells and Cancer. Stem Cells Int 2018; 2018:8908751. [PMID: 30651738 PMCID: PMC6311713 DOI: 10.1155/2018/8908751] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 10/16/2018] [Accepted: 10/29/2018] [Indexed: 01/02/2023] Open
Abstract
Protein acetylation is one of the most important posttranslational modifications catalyzed by acetyltransferases and deacetylases, through the addition and removal of acetyl groups to lysine residues. Lysine acetylation can affect protein-nucleic acid or protein-protein interactions and protein localization, transport, stability, and activity. It regulates the function of a large variety of proteins, including histones, oncoproteins, tumor suppressors, and transcription factors, thus representing a crucial regulator of several biological processes with particular prominent roles in transcription and metabolism. Thus, it is unsurprising that alteration of protein acetylation is involved in human disease, including metabolic disorders and cancers. In this context, different hematological and solid tumors are characterized by deregulation of the protein acetylation pattern as a result of genetic or epigenetic changes. The imbalance between acetylation and deacetylation of histone or nonhistone proteins is also involved in the modulation of the self-renewal and differentiation ability of stem cells, including cancer stem cells. Here, we summarize a combination of in vitro and in vivo studies, undertaken on a set of acetyltransferases, and discuss the physiological and pathological roles of this class of enzymes. We also review the available data on the involvement of acetyltransferases in the regulation of stem cell renewal and differentiation in both normal and cancer cell population.
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27
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Yusenko M, Jakobs A, Klempnauer KH. A novel cell-based screening assay for small-molecule MYB inhibitors identifies podophyllotoxins teniposide and etoposide as inhibitors of MYB activity. Sci Rep 2018; 8:13159. [PMID: 30177851 PMCID: PMC6120916 DOI: 10.1038/s41598-018-31620-1] [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: 03/06/2018] [Accepted: 07/03/2018] [Indexed: 12/15/2022] Open
Abstract
The transcription factor MYB plays key roles in hematopoietic cells and has been implicated the development of leukemia. MYB has therefore emerged as an attractive target for drug development. Recent work has suggested that targeting MYB by small-molecule inhibitors is feasible and that inhibition of MYB has potential as a therapeutic approach against acute myeloid leukemia. To facilitate the identification of small-molecule MYB inhibitors we have re-designed and improved a previously established cell-based screening assay and have employed it to screen a natural product library for potential inhibitors. Our work shows that teniposide and etoposide, chemotherapeutic agents causing DNA-damage by inhibiting topoisomerase II, potently inhibit MYB activity and induce degradation of MYB in AML cell lines. MYB inhibition is suppressed by caffeine, suggesting that MYB is inhibited indirectly via DNA-damage signalling. Importantly, ectopic expression of an activated version of MYB in pro-myelocytic NB4 cells diminished the anti-proliferative effects of teniposide, suggesting that podophyllotoxins disrupt the proliferation of leukemia cells not simply by inducing general DNA-damage but that their anti-proliferative effects are boosted by inhibition of MYB. Teniposide and etoposide therefore act like double-edged swords that might be particularly effective to inhibit tumor cells with deregulated MYB.
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Affiliation(s)
- Maria Yusenko
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149, Münster, Germany
| | - Anke Jakobs
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149, Münster, Germany
| | - Karl-Heinz Klempnauer
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149, Münster, Germany.
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28
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Takei H, Kobayashi SS. Targeting transcription factors in acute myeloid leukemia. Int J Hematol 2018; 109:28-34. [PMID: 29956082 DOI: 10.1007/s12185-018-2488-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 06/12/2018] [Accepted: 06/25/2018] [Indexed: 12/28/2022]
Abstract
Transcription factors recognize and bind to consensus sequence elements that are specific for each transcription factor, and the transcription factors then regulate downstream gene expression. In the bone marrow, transcription factors, such as C/EBPα, PU.1, and RUNX1, control essential genes to maintain the normal hematopoietic system. Dysregulation of transcription factors caused by gene mutations, chromosomal aberrations, or aberrant expression can lead to cancer, including acute myeloid leukemia. In the past, transcription factors were not considered "druggable" targets. However, a better understanding of the pathology of malignant tumors and mechanisms of transcriptional regulation has enabled us to develop novel therapeutic strategies that target transcription factors. In this review, we focus on transcription factors that play important roles in leukemogenesis and current efforts and prospects in the development of transcriptional therapy. We believe that such a therapeutic approach will benefit patients with cancers that involve acute myeloid leukemia in the near future.
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Affiliation(s)
- Hisashi Takei
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, USA
- Department of Hematology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Susumu S Kobayashi
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, USA.
- Division of Translational Genomics, Exploratory Oncology Research and Clinical Trial Center, National Cancer Center, 6-5-1 Kashiwanoha, Kashiwa-shi, Chiba, 277-8577, Japan.
- Harvard Stem Cell Institute, Harvard Medical School, Boston, USA.
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29
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Liu X, Xu Y, Han L, Yi Y. Reassessing the Potential of Myb-targeted Anti-cancer Therapy. J Cancer 2018; 9:1259-1266. [PMID: 29675107 PMCID: PMC5907674 DOI: 10.7150/jca.23992] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/28/2018] [Indexed: 01/27/2023] Open
Abstract
Transcription factor MYB is essential for the tumorigenesis of multiple cancers, especially leukemia, breast cancer, colon cancer, adenoid cystic carcinoma and brain cancer. Thus, MYB has been regarded as an attractive target for tumor therapy. However, pioneer studies of antisense oligodeoxynucleotides against MYB, which were launched three decades ago in leukemia therapy, were discontinued because of their unsatisfactory clinical outcomes. In recent years, the roles of MYB in tumor transformation have become increasingly clear. Moreover, the regulatory mechanisms of MYB, such as the vital effects of MYB co-regulators on MYB activity and of transcriptional elongation on MYB expression, have been unveiled. These observations have underpinned novel approaches in inhibiting MYB. This review discusses the structure, function and regulation of MYB, focusing on recent insights into MYB-associated oncogenesis and how MYB-targeted therapeutics can be explored. Additionally, the main MYB-targeted therapies, including novel genetic therapy, RNA interference, microRNAs and low-molecular-weight compounds, which are especially promising inhibitors that target MYB co-regulators and transcriptional elongation, are described, and their prospects are assessed.
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Affiliation(s)
- Xiaofeng Liu
- Department of Hematology, the Second Xiangya Hospital, Central South University, Changsha, Hunan Province, P.R. China
| | - Yunxiao Xu
- Department of Hematology, the Second Xiangya Hospital, Central South University, Changsha, Hunan Province, P.R. China
| | - Liping Han
- School of Life Science, Changchun Normal University, Changchun, Jilin Province, P.R. China
| | - Yan Yi
- Department of Hematology, the Second Xiangya Hospital, Central South University, Changsha, Hunan Province, P.R. China
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30
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Coulibaly A, Haas A, Steinmann S, Jakobs A, Schmidt TJ, Klempnauer KH. The natural anti-tumor compound Celastrol targets a Myb-C/EBPβ-p300 transcriptional module implicated in myeloid gene expression. PLoS One 2018; 13:e0190934. [PMID: 29394256 PMCID: PMC5796697 DOI: 10.1371/journal.pone.0190934] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 12/22/2017] [Indexed: 12/31/2022] Open
Abstract
Myb is a key regulator of hematopoietic progenitor cell proliferation and differentiation and has emerged as a potential target for the treatment of acute leukemia. Using a myeloid cell line with a stably integrated Myb-inducible reporter gene as a screening tool we have previously identified Celastrol, a natural compound with anti-tumor activity, as a potent Myb inhibitor that disrupts the interaction of Myb with the co-activator p300. We showed that Celastrol inhibits the proliferation of acute myeloid leukemia (AML) cells and prolongs the survival of mice in an in vivo model of AML, demonstrating that targeting Myb with a small-molecule inhibitor is feasible and might have potential as a therapeutic approach against AML. Recently we became aware that the reporter system used for Myb inhibitor screening also responds to inhibition of C/EBPβ, a transcription factor known to cooperate with Myb in myeloid cells. By re-investigating the inhibitory potential of Celastrol we have found that Celastrol also strongly inhibits the activity of C/EBPβ by disrupting its interaction with the Taz2 domain of p300. Together with previous studies our work reveals that Celastrol independently targets Myb and C/EBPβ by disrupting the interaction of both transcription factors with p300. Myb, C/EBPβ and p300 cooperate in myeloid-specific gene expression and, as shown recently, are associated with so-called super-enhancers in AML cells that have been implicated in the maintenance of the leukemia. We hypothesize that the ability of Celastrol to disrupt the activity of a transcriptional Myb-C/EBPβ-p300 module might explain its promising anti-leukemic activity.
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Affiliation(s)
- Anna Coulibaly
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Astrid Haas
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Simone Steinmann
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Anke Jakobs
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Thomas J. Schmidt
- Institute for Pharmaceutical Biology and Phytochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Karl-Heinz Klempnauer
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
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31
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Ramaswamy K, Forbes L, Minuesa G, Gindin T, Brown F, Kharas MG, Krivtsov AV, Armstrong SA, Still E, de Stanchina E, Knoechel B, Koche R, Kentsis A. Peptidomimetic blockade of MYB in acute myeloid leukemia. Nat Commun 2018; 9:110. [PMID: 29317678 PMCID: PMC5760651 DOI: 10.1038/s41467-017-02618-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 12/13/2017] [Indexed: 02/08/2023] Open
Abstract
Aberrant gene expression is a hallmark of acute leukemias. MYB-driven transcriptional coactivation with CREB-binding protein (CBP)/P300 is required for acute lymphoblastic and myeloid leukemias, including refractory MLL-rearranged leukemias. Using structure-guided molecular design, we developed a peptidomimetic inhibitor MYBMIM that interferes with the assembly of the molecular MYB:CBP/P300 complex and rapidly accumulates in the nuclei of AML cells. Treatment of AML cells with MYBMIM led to the dissociation of the MYB:CBP/P300 complex in cells, its displacement from oncogenic enhancers enriched for MYB binding sites, and downregulation of MYB-dependent gene expression, including of MYC and BCL2 oncogenes. AML cells underwent mitochondrial apoptosis in response to MYBMIM, which was partially rescued by ectopic expression of BCL2. MYBMIM impeded leukemia growth and extended survival of immunodeficient mice engrafted with primary patient-derived MLL-rearranged leukemia cells. These findings elucidate the dependence of human AML on aberrant transcriptional coactivation, and establish a pharmacologic approach for its therapeutic blockade.
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Affiliation(s)
- Kavitha Ramaswamy
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, 10065, NY, USA
| | - Lauren Forbes
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA
- Departments of Pediatrics, Pharmacology, and Physiology & Biophysics, Weill Cornell Medical College, Cornell University, New York, NY, 10065, USA
| | - Gerard Minuesa
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Tatyana Gindin
- Department of Pathology and Cell Biology, Columbia University Medical Center and New York Presbyterian Hospital, New York, NY, 10065, USA
| | - Fiona Brown
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Michael G Kharas
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Andrei V Krivtsov
- Center for Epigenetics Research, Sloan Kettering Institute, New York, NY, 10065, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
| | - Scott A Armstrong
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, 10065, NY, USA
- Center for Epigenetics Research, Sloan Kettering Institute, New York, NY, 10065, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
| | - Eric Still
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Elisa de Stanchina
- Antitumor Assessment Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Birgit Knoechel
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
| | - Richard Koche
- Center for Epigenetics Research, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Alex Kentsis
- Molecular Pharmacology Program, Sloan Kettering Institute, New York, NY, 10065, USA.
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, 10065, NY, USA.
- Departments of Pediatrics, Pharmacology, and Physiology & Biophysics, Weill Cornell Medical College, Cornell University, New York, NY, 10065, USA.
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32
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Xu Y, Milazzo JP, Somerville TDD, Tarumoto Y, Huang YH, Ostrander EL, Wilkinson JE, Challen GA, Vakoc CR. A TFIID-SAGA Perturbation that Targets MYB and Suppresses Acute Myeloid Leukemia. Cancer Cell 2018; 33:13-28.e8. [PMID: 29316427 PMCID: PMC5764110 DOI: 10.1016/j.ccell.2017.12.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/22/2017] [Accepted: 12/05/2017] [Indexed: 01/08/2023]
Abstract
Targeting of general coactivators is an emerging strategy to interfere with oncogenic transcription factors (TFs). However, coactivator perturbations often lead to pleiotropic effects by influencing numerous TFs. Here we identify TAF12, a subunit of TFIID and SAGA coactivator complexes, as a selective requirement for acute myeloid leukemia (AML) progression. We trace this dependency to a direct interaction between the TAF12/TAF4 histone-fold heterodimer and the transactivation domain of MYB, a TF with established roles in leukemogenesis. Ectopic expression of the TAF4 histone-fold fragment can efficiently squelch TAF12 in cells, suppress MYB, and regress AML in mice. Our study reveals a strategy for potent MYB inhibition in AML and highlights how an oncogenic TF can be selectively neutralized by targeting a general coactivator complex.
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Affiliation(s)
- Yali Xu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; Molecular and Cellular Biology Program, Stony Brook University, New York, NY 11794, USA
| | - Joseph P Milazzo
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | | | - Yusuke Tarumoto
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Yu-Han Huang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Elizabeth L Ostrander
- Division of Oncology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - John E Wilkinson
- ULAM/Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Grant A Challen
- Division of Oncology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
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33
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Frerich CA, Brayer KJ, Painter BM, Kang H, Mitani Y, El-Naggar AK, Ness SA. Transcriptomes define distinct subgroups of salivary gland adenoid cystic carcinoma with different driver mutations and outcomes. Oncotarget 2017; 9:7341-7358. [PMID: 29484115 PMCID: PMC5800907 DOI: 10.18632/oncotarget.23641] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/08/2017] [Indexed: 12/30/2022] Open
Abstract
The relative rarity of salivary gland adenoid cystic carcinoma (ACC) and its slow growing yet aggressive nature has complicated the development of molecular markers for patient stratification. To analyze molecular differences linked to the protracted disease course of ACC and metastases that form 5 or more years after diagnosis, detailed RNA-sequencing (RNA-seq) analysis was performed on 68 ACC tumor samples, starting with archived, formalin-fixed paraffin-embedded (FFPE) samples up to 25 years old, so that clinical outcomes were available. A statistical peak-finding approach was used to classify the tumors that expressed MYB or MYBL1, which had overlapping gene expression signatures, from a group that expressed neither oncogene and displayed a unique phenotype. Expression of MYB or MYBL1 was closely correlated to the expression of the SOX4 and EN1 genes, suggesting that they are direct targets of Myb proteins in ACC tumors. Unsupervised hierarchical clustering identified a subgroup of approximately 20% of patients with exceptionally poor overall survival (median less than 30 months) and a unique gene expression signature resembling embryonic stem cells. The results provide a strategy for stratifying ACC patients and identifying the high-risk, poor-outcome group that are candidates for personalized therapies.
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Affiliation(s)
- Candace A Frerich
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
| | - Kathryn J Brayer
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.,University of New Mexico Comprehensive Cancer Center, Albuquerque, NM, USA
| | - Brandon M Painter
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
| | - Huining Kang
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
| | - Yoshitsugu Mitani
- Head and Neck Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Adel K El-Naggar
- Head and Neck Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Scott A Ness
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.,University of New Mexico Comprehensive Cancer Center, Albuquerque, NM, USA
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34
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Falkenberg KD, Jakobs A, Matern JC, Dörner W, Uttarkar S, Trentmann A, Steinmann S, Coulibaly A, Schomburg C, Mootz HD, Schmidt TJ, Klempnauer KH. Withaferin A, a natural compound with anti-tumor activity, is a potent inhibitor of transcription factor C/EBPβ. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1349-1358. [PMID: 28476645 DOI: 10.1016/j.bbamcr.2017.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 04/27/2017] [Accepted: 05/01/2017] [Indexed: 02/07/2023]
Abstract
Recent work has shown that deregulation of the transcription factor Myb contributes to the development of leukemia and several other human cancers, making Myb and its cooperation partners attractive targets for drug development. By employing a myeloid Myb-reporter cell line we have identified Withaferin A (WFA), a natural compound that exhibits anti-tumor activities, as an inhibitor of Myb-dependent transcription. Analysis of the inhibitory mechanism of WFA showed that WFA is a significantly more potent inhibitor of C/EBPβ, a transcription factor cooperating with Myb in myeloid cells, than of Myb itself. We show that WFA covalently modifies specific cysteine residues of C/EBPβ, resulting in the disruption of the interaction of C/EBPβ with the co-activator p300. Our work identifies C/EBPβ as a novel direct target of WFA and highlights the role of p300 as a crucial co-activator of C/EBPβ. The finding that WFA is a potent inhibitor of C/EBPβ suggests that inhibition of C/EBPβ might contribute to the biological activities of WFA.
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Affiliation(s)
- Kim D Falkenberg
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Anke Jakobs
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Julian C Matern
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Wolfgang Dörner
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Sagar Uttarkar
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Amke Trentmann
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Simone Steinmann
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Anna Coulibaly
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Caroline Schomburg
- Institute for Pharmaceutical Biology and Phytochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Henning D Mootz
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Thomas J Schmidt
- Institute for Pharmaceutical Biology and Phytochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany
| | - Karl-Heinz Klempnauer
- Institute for Biochemistry, Westfälische-Wilhelms-Universität, D-48149 Münster, Germany.
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Zubair H, Azim S, Ahmad A, Khan MA, Patel GK, Singh S, Singh AP. Cancer Chemoprevention by Phytochemicals: Nature's Healing Touch. Molecules 2017; 22:molecules22030395. [PMID: 28273819 PMCID: PMC6155418 DOI: 10.3390/molecules22030395] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 02/27/2017] [Accepted: 02/28/2017] [Indexed: 12/28/2022] Open
Abstract
Phytochemicals are an important part of traditional medicine and have been investigated in detail for possible inclusion in modern medicine as well. These compounds often serve as the backbone for the synthesis of novel therapeutic agents. For many years, phytochemicals have demonstrated encouraging activity against various human cancer models in pre-clinical assays. Here, we discuss select phytochemicals—curcumin, epigallocatechin-3-gallate (EGCG), resveratrol, plumbagin and honokiol—in the context of their reported effects on the processes of inflammation and oxidative stress, which play a key role in tumorigenesis. We also discuss the emerging evidence on modulation of tumor microenvironment by these phytochemicals which can possibly define their cancer-specific action. Finally, we provide recent updates on how low bioavailability, a major concern with phytochemicals, is being circumvented and the general efficacy being improved, by synthesis of novel chemical analogs and nanoformulations.
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Affiliation(s)
- Haseeb Zubair
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
| | - Shafquat Azim
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
| | - Aamir Ahmad
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
| | - Mohammad Aslam Khan
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
| | - Girijesh Kumar Patel
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
| | - Seema Singh
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
- Department of Molecular Biology and Biochemistry, College of Medicine, University of South Alabama, Mobile, AL 36688, USA.
| | - Ajay Pratap Singh
- Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL 36604, USA.
- Department of Molecular Biology and Biochemistry, College of Medicine, University of South Alabama, Mobile, AL 36688, USA.
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Uttarkar S, Frampton J, Klempnauer KH. Targeting the transcription factor Myb by small-molecule inhibitors. Exp Hematol 2016; 47:31-35. [PMID: 28017646 DOI: 10.1016/j.exphem.2016.12.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 12/10/2016] [Indexed: 11/18/2022]
Abstract
The transcription factor Myb is a key regulator of hematopoietic cell proliferation, differentiation, and survival and has been implicated in the development of leukemia and several other human cancers. Pharmacological inhibition of Myb is therefore emerging as a potential therapeutic strategy. Recently, the first low-molecular-weight compounds that show Myb inhibitory activity have been identified. Characterization of these compounds suggests disruption of the protein-protein-interaction of Myb and the coactivator p300 as a suitable strategy to inhibit Myb.
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Affiliation(s)
| | - Jon Frampton
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
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