1
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Guo M, Li X, Tao W, Teng F, Li C. Vibrio splendidus infection promotes circRNA-FGL1-regulated coelomocyte apoptosis via competitive binding to Myc with the deubiquitinase OTUB1 in Apostichopus japonicus. PLoS Pathog 2024; 20:e1012463. [PMID: 39146353 PMCID: PMC11349225 DOI: 10.1371/journal.ppat.1012463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 08/27/2024] [Accepted: 07/30/2024] [Indexed: 08/17/2024] Open
Abstract
Circular RNAs (circRNAs) are involved in various physiological and pathological processes in both vertebrates and invertebrates. However, most studies on circRNAs have focused on their roles as endogenous competitive RNAs. Here, we report a novel function of circRNA derived from the Fibrinogen-like protein 1 gene (circ-FGL1) that inhibits coelomocyte apoptosis via competing with the deubiquitinase AjOTUB1 to bind AjMyc in Apostichopus japonicus during Vibrio splendidus infection. The results showed that circ-FGL1 is significantly downregulated in coelomocytes of V. splendidus-induced A. japonicus and negatively regulates coelomocyte apoptosis through the AjBax-AjCyt c pathway. Mechanistically, the deubiquitinase AjOTUB1 and circ-FGL1 could interact with the transcription factor protein AjMyc in the same region with circ-FGL1/AjMyc having greater affinity. Under normal conditions, high levels of circ-FGL1 bind directly to AjMyc, inhibiting the deubiquitylation of AjMyc by AjOTUB1 and leading to the degradation of AjMyc. After V. splendidus infection, AjMyc disassociates from the depressed expression of circ-FGL1, promoting its deubiquitylation by binding to the induced deubiquitinase AjOTUB1 to inhibit its degradation. AjMyc is then transferred to the nucleus and promotes the transcription of AjCyt c and AjBax to induce coelomocyte apoptosis. The new finding will expand our present outstanding on the functional role of circRNAs and suggest new therapeutic targets for the treatment of echinoderms during bacterial invasion.
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Affiliation(s)
- Ming Guo
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Marine Sciences, Ningbo University, Ningbo, China
| | - Xin Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Marine Sciences, Ningbo University, Ningbo, China
| | - Wenjun Tao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Marine Sciences, Ningbo University, Ningbo, China
| | - Fei Teng
- College of Mathematics and Computer, Jilin Normal University, Siping, Jilin, China
| | - Chenghua Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, School of Marine Sciences, Ningbo University, Ningbo, China
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2
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Solta A, Ernhofer B, Boettiger K, Megyesfalvi Z, Heeke S, Hoda MA, Lang C, Aigner C, Hirsch FR, Schelch K, Döme B. Small cells - big issues: biological implications and preclinical advancements in small cell lung cancer. Mol Cancer 2024; 23:41. [PMID: 38395864 PMCID: PMC10893629 DOI: 10.1186/s12943-024-01953-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 01/31/2024] [Indexed: 02/25/2024] Open
Abstract
Current treatment guidelines refer to small cell lung cancer (SCLC), one of the deadliest human malignancies, as a homogeneous disease. Accordingly, SCLC therapy comprises chemoradiation with or without immunotherapy. Meanwhile, recent studies have made significant advances in subclassifying SCLC based on the elevated expression of the transcription factors ASCL1, NEUROD1, and POU2F3, as well as on certain inflammatory characteristics. The role of the transcription regulator YAP1 in defining a unique SCLC subset remains to be established. Although preclinical analyses have described numerous subtype-specific characteristics and vulnerabilities, the so far non-existing clinical subtype distinction may be a contributor to negative clinical trial outcomes. This comprehensive review aims to provide a framework for the development of novel personalized therapeutic approaches by compiling the most recent discoveries achieved by preclinical SCLC research. We highlight the challenges faced due to limited access to patient material as well as the advances accomplished by implementing state-of-the-art models and methodologies.
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Affiliation(s)
- Anna Solta
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Büsra Ernhofer
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Kristiina Boettiger
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Zsolt Megyesfalvi
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary
- National Koranyi Institute of Pulmonology, Budapest, Hungary
| | - Simon Heeke
- Department of Thoracic Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Mir Alireza Hoda
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Christian Lang
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Division of Pulmonology, Department of Medicine II, Medical University of Vienna, Vienna, Austria
| | - Clemens Aigner
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Fred R Hirsch
- Division of Medical Oncology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
- Center for Thoracic Oncology, Mount Sinai Health System, Tisch Cancer Institute, New York, NY, USA.
| | - Karin Schelch
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
- Center for Cancer Research, Medical University of Vienna, Vienna, Austria
| | - Balazs Döme
- Department of Thoracic Surgery, Comprehensive Cancer Center, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
- Department of Thoracic Surgery, Semmelweis University and National Institute of Oncology, Budapest, Hungary.
- National Koranyi Institute of Pulmonology, Budapest, Hungary.
- Department of Translational Medicine, Lund University, Lund, Sweden.
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3
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Chen M, Li S, Jiang L. Clinicopathological molecular characterizations of sinonasal NUT carcinoma: a report of two cases and a literature review. Front Oncol 2024; 13:1296862. [PMID: 38239638 PMCID: PMC10794637 DOI: 10.3389/fonc.2023.1296862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 12/01/2023] [Indexed: 01/22/2024] Open
Abstract
Background Nuclear protein in testis (NUT) carcinoma (NC) is a rare, aggressive tumor with a typical NUTM1 gene rearrangement. Methods Herein, we report a series of 2 cases of sinonasal NC: one in a 16-year-old woman and one in a 37-year-old man. Immunohistochemistry (IHC) staining for NUT (C52B1), fluorescence in situ hybridization (FISH), and next generation sequencing (NGS) sequencing were performed to investigate the morphological and genetic features of sinonasal NC. Results The two cases presented similar pathological features and IHC markers, and typical morphological changes, including undifferentiated cells and abrupt keratinization, were observed, with numerous mitotic figures and widespread tumor necrosis. Diffuse expression of NUT, CK, p63, and p40 was noted, while the tumors were negative for synaptophysin, chromogranin A, S-100, EBV-ISH, and PD-L1. Both tumors harbored a NUTM1 rearrangement. Subsequent sequencing revealed a rare BRD3::NUTM1 fusion and a classic BRD4::NUTM1 fusion. In addition, MCL1 copy number gain (2.1), low tumor mutation burden and stable microsatellites, were also confirmed. Case 1 received surgery and chemoradiotherapy but died 13 months after local recurrence and subsequent lung and bone metastasis. Case 2 underwent chemoradiotherapy and unfortunately died from the disease 6 months later. A review of all previously reported cases of sinonasal NCs (n=55) revealed that these tumors occur more frequently in female pediatric patients (n=11, male: female =3:8), whereas this sex difference is not observed in adult patients (n=44, male: female =23:21). The median survival times of pediatric and adult patients were 17 and 13.8 months, respectively. Conclusion Sinonasal NC presents typical undifferentiated or poorly differentiated cells, abrupt keratinization features and heterogeneous genotypes, including BRD4::NUTM1 and BRD3::NUTM1 fusions, with low tumor mutation burden and stable microsatellites.
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Affiliation(s)
| | | | - Lili Jiang
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
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4
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Harris EL, Roy V, Montagne M, Rose AMS, Livesey H, Reijnders MRF, Hobson E, Sansbury FH, Willemsen MH, Pfundt R, Warren D, Long V, Carr IM, Brunner HG, Sheridan EG, Firth HV, Lavigne P, Poulter JA. A recurrent de novo MAX p.Arg60Gln variant causes a syndromic overgrowth disorder through differential expression of c-Myc target genes. Am J Hum Genet 2024; 111:119-132. [PMID: 38141607 PMCID: PMC10806738 DOI: 10.1016/j.ajhg.2023.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 11/23/2023] [Accepted: 11/29/2023] [Indexed: 12/25/2023] Open
Abstract
Cyclin D2 (CCND2) stabilization underpins a range of macrocephaly-associated disorders through mutation of CCND2 or activating mutations in upstream genes encoding PI3K-AKT pathway components. Here, we describe three individuals with overlapping macrocephaly-associated phenotypes who carry the same recurrent de novo c.179G>A (p.Arg60Gln) variant in Myc-associated factor X (MAX). The mutation, located in the b-HLH-LZ domain, causes increased intracellular CCND2 through increased transcription but it does not cause stabilization of CCND2. We show that the purified b-HLH-LZ domain of MAXArg60Gln (Max∗Arg60Gln) binds its target E-box sequence with a lower apparent affinity. This leads to a more efficient heterodimerization with c-Myc resulting in an increase in transcriptional activity of c-Myc in individuals carrying this mutation. The recent development of Omomyc-CPP, a cell-penetrating b-HLH-LZ-domain c-Myc inhibitor, provides a possible therapeutic option for MAXArg60Gln individuals, and others carrying similar germline mutations resulting in dysregulated transcriptional c-Myc activity.
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Affiliation(s)
- Erica L Harris
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, UK
| | - Vincent Roy
- Département de Biochimie et Génomique Fonctionnelle, PROTÉO et Institut de Pharmacologie de Sherbrooke. University of Sherbrooke, Sherbrooke, QC, Canada
| | - Martin Montagne
- Département de Biochimie et Génomique Fonctionnelle, PROTÉO et Institut de Pharmacologie de Sherbrooke. University of Sherbrooke, Sherbrooke, QC, Canada
| | - Ailsa M S Rose
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, UK
| | - Helen Livesey
- Leeds Teaching Hospitals NHS Trust, Leeds, UK; All Wales Medical Genomics Service, NHS Wales Cardiff and Vale University Health Board, Cardiff, UK
| | - Margot R F Reijnders
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Emma Hobson
- Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Francis H Sansbury
- All Wales Medical Genomics Service, NHS Wales Cardiff and Vale University Health Board, Cardiff, UK
| | - Marjolein H Willemsen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Rolph Pfundt
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | | | - Vernon Long
- Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Ian M Carr
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, UK
| | - Han G Brunner
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Eamonn G Sheridan
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, UK; Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Helen V Firth
- Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK; Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - Pierre Lavigne
- Département de Biochimie et Génomique Fonctionnelle, PROTÉO et Institut de Pharmacologie de Sherbrooke. University of Sherbrooke, Sherbrooke, QC, Canada.
| | - James A Poulter
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, UK.
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5
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Wangsiricharoen S, Wakely PE, Prieto VG, Yu W. Sarcoma with MGA::NUTM1 fusion: a report of three cases and literature review. Histopathology 2023; 83:712-721. [PMID: 37442637 DOI: 10.1111/his.15004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/19/2023] [Accepted: 06/24/2023] [Indexed: 07/15/2023]
Abstract
AIMS NUTM1-rearranged sarcoma is an emerging entity that differs from NUT carcinoma at the molecular level, with most of the former tumours harbouring fusions involving genes in the MYC-associated factor X dimerization (MAD) transcription family (MXD1, MXD4, MXI1 [or MXD2], and MGA). MGA::NUTM1 is one of the most recently described novel gene fusions associated with NUTM1-rearranged sarcoma. Herein we describe the clinicopathologic features of three sarcomas with an MGA::NUTM1 fusion. METHODS AND RESULTS The three study patients were male, with an age range of 10-28 years. The tumour sites were deep soft tissue of the thigh, the chest wall, and the pelvis. All three tumours were aggressive, with multiple recurrences and metastases. Histologically, the tumours were composed of monotonous spindle, round, or epithelioid cells in variably hyalinized stroma and prominent aggregates of amianthoid fibre-like collagen or collagen rosettes. Mitotic activity was relatively low (5-12 mitotic figures per 10 hhpf). All tumours tested expressed NUT, with one tumour having S100 protein expression and two tumours having CD99 and CD56 expression. The genetic breakpoints were MGA exon 21, MGA exon 22, and NUTM1 exon 3. CONCLUSION MGA::NUTM1 sarcoma often exhibits hyalinized stroma with amianthoid fibre-like collagen or collagen rosettes in the presence of monotonous round, epithelioid, or spindle cell morphology. NUT immunohistochemistry and molecular testing can help confirm the diagnosis.
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Affiliation(s)
| | - Paul E Wakely
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Victor G Prieto
- Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Wendong Yu
- Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
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6
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Georgantzoglou N, Aghighi M, Cote G, Hung YP, Kerr DA, Pettus J, Linos K. Primary Spindle Cell Sarcoma of the Lung with MGA::NUTM1 Fusion: An Extremely Rare Case of a Potentially Emerging Entity and Review of the Literature. Int J Surg Pathol 2022; 30:931-938. [PMID: 35388715 DOI: 10.1177/10668969221092125] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Originally described in a rare subset of poorly differentiated squamous cell carcinomas termed NUT carcinomas, NUTM1 rearrangements are now known to characterize a wide spectrum of neoplasms including sarcomas, poromas/porocarcinomas, unclassified adnexal carcinomas and pediatric acute lymphoblastic leukemia. The advent of next-generation sequencing (NGS) has led to the identification of a multitude of novel fusion partners in addition to BRD4, which was initially reported in the majority of NUT carcinomas. NUTM1-rearranged sarcomas usually harbor fusions with the MAD gene family (MXD1, MXD4, MGA) and present as spindle cell proliferations in diverse locations in patients of all ages. Herein, we present a very rare case of spindle cell sarcoma of the lung, which harbored a NUTM1::MGA fusion and offer a comprehensive update of the recent data.
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Affiliation(s)
- Natalia Georgantzoglou
- Department of Pathology and Laboratory Medicine, 22916Dartmouth Hitchcock Medical Center, Lebanon, NH, USA
| | - Maryam Aghighi
- Department of Pathology, 21640Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Gregory Cote
- Department of Hematology/Oncology, 2348Massachusetts General Hospital, Boston, MA, USA
| | - Yin P Hung
- Department of Pathology, 2348Massachusetts General Hospital, Boston, MA, USA
| | - Darcy A Kerr
- Department of Pathology and Laboratory Medicine, 22916Dartmouth Hitchcock Medical Center, Lebanon, NH, USA.,Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Jason Pettus
- Department of Pathology and Laboratory Medicine, 22916Dartmouth Hitchcock Medical Center, Lebanon, NH, USA.,Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Konstantinos Linos
- Department of Pathology and Laboratory Medicine, 22916Dartmouth Hitchcock Medical Center, Lebanon, NH, USA.,Geisel School of Medicine at Dartmouth, Hanover, NH, USA
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7
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Wei Y, Redel C, Ahlner A, Lemak A, Johansson-Åkhe I, Houliston S, Kenney TMG, Tamachi A, Morad V, Duan S, Andrews DW, Wallner B, Sunnerhagen M, Arrowsmith CH, Penn LZ. The MYC oncoprotein directly interacts with its chromatin cofactor PNUTS to recruit PP1 phosphatase. Nucleic Acids Res 2022; 50:3505-3522. [PMID: 35244724 PMCID: PMC8989513 DOI: 10.1093/nar/gkac138] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 01/11/2022] [Accepted: 02/28/2022] [Indexed: 02/07/2023] Open
Abstract
Despite MYC dysregulation in most human cancers, strategies to target this potent oncogenic driver remain an urgent unmet need. Recent evidence shows the PP1 phosphatase and its regulatory subunit PNUTS control MYC phosphorylation, chromatin occupancy, and stability, however the molecular basis remains unclear. Here we demonstrate that MYC interacts directly with PNUTS through the MYC homology Box 0 (MB0), a highly conserved region recently shown to be important for MYC oncogenic activity. By NMR we identified a distinct peptide motif within MB0 that interacts with PNUTS residues 1–148, a functional unit, here termed PNUTS amino-terminal domain (PAD). Using NMR spectroscopy we determined the solution structure of PAD, and characterised its MYC-binding patch. Point mutations of residues at the MYC-PNUTS interface significantly weaken their interaction both in vitro and in vivo, leading to elevated MYC phosphorylation. These data demonstrate that the MB0 region of MYC directly interacts with the PAD of PNUTS, which provides new insight into the control mechanisms of MYC as a regulator of gene transcription and a pervasive cancer driver.
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Affiliation(s)
- Yong Wei
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada.,Sunnybrook Research Institute, 2075 Bayview Ave. Toronto, ON, M4N 3M5, Canada
| | - Cornelia Redel
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Alexandra Ahlner
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Alexander Lemak
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada
| | - Isak Johansson-Åkhe
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Scott Houliston
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada
| | - Tristan M G Kenney
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Aaliya Tamachi
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada
| | - Vivian Morad
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | | | - David W Andrews
- Sunnybrook Research Institute, 2075 Bayview Ave. Toronto, ON, M4N 3M5, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Björn Wallner
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Maria Sunnerhagen
- Department of Physics, Chemistry, and Biology, Linköping University, SE-581 83 Linköping, Sweden
| | - Cheryl H Arrowsmith
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Structural Genomics Consortium (SGC), University of Toronto, 101 College St., Suite 700, Toronto, ON, M5G 1L7, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
| | - Linda Z Penn
- Princess Margaret Cancer Centre, University Health Network, 101 College St, Toronto, ON M5G 0A3, Canada.,Department of Medical Biophysics, University of Toronto, 101 College St, Toronto, ON M5G 1L7, Canada
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8
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Nagasaka M, Inoue Y, Yoshida M, Miyajima C, Morishita D, Tokugawa M, Nakamoto H, Sugano M, Ohoka N, Hayashi H. The deubiquitinating enzyme USP17 regulates c‐Myc levels and controls cell proliferation and glycolysis. FEBS Lett 2022; 596:465-478. [DOI: 10.1002/1873-3468.14296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/09/2022] [Accepted: 01/12/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Mai Nagasaka
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Yasumichi Inoue
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
- Department of Innovative Therapeutics Sciences Cooperative Major in Nanopharmaceutical Sciences Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Manaka Yoshida
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Chiharu Miyajima
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
- Department of Innovative Therapeutics Sciences Cooperative Major in Nanopharmaceutical Sciences Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Daisuke Morishita
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
- Chordia Therapeutics Inc 251‐0012 Kanagawa Japan
| | - Muneshige Tokugawa
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Haruna Nakamoto
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Mayumi Sugano
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
| | - Nobumichi Ohoka
- Division of Molecular Target and Gene Therapy Products National Institute of Health Sciences 210‐9501 Kanagawa Japan
| | - Hidetoshi Hayashi
- Department of Cell Signaling Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
- Department of Innovative Therapeutics Sciences Cooperative Major in Nanopharmaceutical Sciences Graduate School of Pharmaceutical Sciences Nagoya City University 467‐8603 Nagoya Japan
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9
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Prasad RR, Mishra DK, Kumar M, Yadava PK. Human telomerase reverse transcriptase promotes the epithelial to mesenchymal transition in lung cancer cells by enhancing c-MET upregulation. Heliyon 2022; 8:e08673. [PMID: 35024489 PMCID: PMC8732784 DOI: 10.1016/j.heliyon.2021.e08673] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/01/2021] [Accepted: 12/21/2021] [Indexed: 10/25/2022] Open
Abstract
Human telomerase reverse transcriptase (hTERT), the essential catalytic subunit of telomerase, is associated with telomere homeostasis to prevent replicative senescence and cellular aging. However, hTERT reactivation also has been linked to the acquisition of several hallmarks of cancer, although the underlying mechanism beyond telomere extension remains elusive. This study demonstrated that hTERT overexpression promotes, whereas its inhibition by shRNA suppresses, epithelial-mesenchymal transition (EMT) in lung cancer cells (A549 and H1299). We found that hTERT modulates the expression of EMT markers E-cadherin, vimentin, and cytokeratin-18a through upregulation of the c-MET. Ectopic expression of hTERT induces expression of c-MET, while hTERT-shRNA treatment significantly decreases the c-MET level in A549 and H1299 through differential expression of p53 and c-Myc. Reporter assay suggests the regulation of c-MET expression by hTERT to be at the promoter level. An increase in c-MET level significantly promotes the expression of mesenchymal markers, including vimentin and N-cadherin, while a notable increase in epithelial markers E-cadherin and cytokeratin-18a is observed after the c-MET knockdown in A549.
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Affiliation(s)
- Ram Raj Prasad
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Deepak Kumar Mishra
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Manoj Kumar
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Pramod Kumar Yadava
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.,Department of Biological Sciences, Indian Institute for Science Education and Research, Berhampur 760010, Odisha, India
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10
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Shen H, Ye F, Xu D, Fang L, Zhang X, Zhu J. The MYEOV-MYC association promotes oncogenic miR-17/93-5p expression in pancreatic ductal adenocarcinoma. Cell Death Dis 2021; 13:15. [PMID: 34930894 PMCID: PMC8688437 DOI: 10.1038/s41419-021-04387-z] [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: 05/19/2021] [Revised: 10/18/2021] [Accepted: 10/29/2021] [Indexed: 12/21/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy worldwide. As metastasis and malignant progression are primarily responsible for the poor clinical outcomes of PDAC, identifying key genes involved in these processes and the underlying molecular mechanisms of PDAC is vital. In this study, by analyzing TCGA PDAC data and matched GTEx data, we found that MYEOV expression is associated with poor survival in PDAC patients and higher in carcinoma tissues than in healthy tissues. Elevated levels of MYEOV led to enhanced cell proliferation, invasion and migration in vitro and in vivo. Transcriptome analysis results revealed that MYEOV mediates global alterations in gene expression profiles in PDAC cells. MiRNA-seq analysis showed that MYEOV regulates the expression levels of miR-17-5p and miR-93-5p, and its depletion resulted in reduced cell proliferation, invasion and migration, as observed in MYEOV-knockdown PDAC cells. These effects are likely due to the ability of MYEOV to regulate enrichment of the transcription factor MYC at the gene promoter regions of the two miRNAs. Furthermore, we identified a complex containing MYEOV and MYC in the nucleus, providing additional evidence for the association of MYEOV with MYC. Taken together, our results suggest that MYEOV promotes oncogenic miR-17/93-5p expression by associating with MYC, contributing to PDAC progression.
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Affiliation(s)
- Hongzhang Shen
- Department of Gastroenterology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Fuqiang Ye
- Huadong Research Institute for Medicine and Biotechniques, Nanjing, China
| | - Dongchao Xu
- Department of Gastroenterology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Liangliang Fang
- The First School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Xiaofeng Zhang
- Department of Gastroenterology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Juanjuan Zhu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China.
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11
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Wu G, Suo C, Yang Y, Shen S, Sun L, Li ST, Zhou Y, Yang D, Wang Y, Cai Y, Wang N, Zhang H, Yang YG, Cao J, Gao P. MYC promotes cancer progression by modulating m 6 A modifications to suppress target gene translation. EMBO Rep 2021; 22:e51519. [PMID: 33426808 DOI: 10.15252/embr.202051519] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 12/07/2020] [Accepted: 12/10/2020] [Indexed: 11/09/2022] Open
Abstract
The MYC oncoprotein activates and represses gene expression in a transcription-dependent or transcription-independent manner. Modification of mRNA emerges as a key gene expression regulatory nexus. We sought to determine whether MYC alters mRNA modifications and report here that MYC promotes cancer progression by down-regulating N6-methyladenosine (m6 A) preferentially in transcripts of a subset of MYC-repressed genes (MRGs). We find that MYC activates the expression of ALKBH5 and reduces m6 A levels in the mRNA of the selected MRGs SPI1 and PHF12. We also show that MYC-regulated m6 A controls the translation of MRG mRNA via the specific m6 A reader YTHDF3. Finally, we find that inhibition of ALKBH5, or overexpression of SPI1 or PHF12, effectively suppresses the growth of MYC-deregulated B-cell lymphomas, both in vitro and in vivo. Our findings uncover a novel mechanism by which MYC suppresses gene expression by altering m6 A modifications in selected MRG transcripts promotes cancer progression.
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Affiliation(s)
- Gongwei Wu
- Guangzhou First People's Hospital, School of Medicine, Institutes for Life Sciences, South China University of Technology, Guangzhou, China.,CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Caixia Suo
- Guangzhou First People's Hospital, School of Medicine, Institutes for Life Sciences, South China University of Technology, Guangzhou, China.,School of Biomedical Sciences and Engineering, Guangzhou International Campus, South China University of Technology, Guangzhou, China
| | - Ying Yang
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, CAS Center for Excellence in Molecular Cell Science, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Shengqi Shen
- CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Linchong Sun
- Guangzhou First People's Hospital, School of Medicine, Institutes for Life Sciences, South China University of Technology, Guangzhou, China.,School of Biomedical Sciences and Engineering, Guangzhou International Campus, South China University of Technology, Guangzhou, China
| | - Shi-Ting Li
- CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Yingli Zhou
- CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Dongdong Yang
- CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Yan Wang
- CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Yongping Cai
- Department of Pathology, School of Medicine, Anhui Medical University, Hefei, Anhui, China
| | - Nana Wang
- Department of Pathology, School of Medicine, Anhui Medical University, Hefei, Anhui, China
| | - Huafeng Zhang
- CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Yun-Gui Yang
- Key Laboratory of Genomic and Precision Medicine, Collaborative Innovation Center of Genetics and Development, CAS Center for Excellence in Molecular Cell Science, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,China National Center for Bioinformation, Beijing, China.,Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
| | - Jie Cao
- Guangzhou First People's Hospital, School of Medicine, Institutes for Life Sciences, South China University of Technology, Guangzhou, China.,School of Biomedical Sciences and Engineering, Guangzhou International Campus, South China University of Technology, Guangzhou, China
| | - Ping Gao
- Guangzhou First People's Hospital, School of Medicine, Institutes for Life Sciences, South China University of Technology, Guangzhou, China.,CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, China.,School of Biomedical Sciences and Engineering, Guangzhou International Campus, South China University of Technology, Guangzhou, China.,Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
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12
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Fuchs O, Bokorova R. Preclinical Studies of PROTACs in Hematological Malignancies. Cardiovasc Hematol Disord Drug Targets 2021; 21:7-22. [PMID: 33687890 DOI: 10.2174/1871529x21666210308111546] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 01/01/2021] [Accepted: 01/23/2021] [Indexed: 06/12/2023]
Abstract
Incorrectly expressed or mutated proteins associated with hematologic malignancies have been generally targeted by chemotherapy using small-molecule inhibitors or monoclonal antibodies. But the majority of these intracellular proteins are without active sites and antigens. PROTACs, proteolysis targeting chimeras, are bifunctional molecules designed to polyubiquitinate and degrade specific pathological proteins of interest (POIs) by hijacking the activity of E3-ubiquitin ligases for POI polyubiquitination and subsequent degradation by the proteasome. This strategy utilizes the ubiquitin-proteasome system for the degradation of specific proteins in the cell. In many cases, including hematologic malignancies, inducing protein degradation as a therapeutic strategy offers therapeutic benefits over classical enzyme inhibition connected with resistance to inhibitors. Limitations of small-molecule inhibitors are shown. PROTACs can polyubiquitinate and mark for degradation of "undruggable"proteins, e.g. transcription factor STAT3 and scaffold proteins. Today, this technology is used in preclinical studies in various hematologic malignancies, mainly for targeting drug-resistant bromodomain and extraterminal proteins and Bruton tyrosine kinase. Several mechanisms limiting selectivity and safety of PROTAC molecules function are also discussed.
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Affiliation(s)
- Ota Fuchs
- Department of Genomics, Institute of Hematology and Blood Transfusion, Prague, Czech Republic
| | - Radka Bokorova
- Department of Genomics, Institute of Hematology and Blood Transfusion, Prague, Czech Republic
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13
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McEvoy CR, Holliday H, Thio N, Mitchell C, Choong DY, Yellapu B, Leong HS, Xu H, Lade S, Browning J, Takano EA, Byrne DJ, Gill AJ, Duong CP, Li J, Fellowes AP, Fox SB, Swarbrick A, Prall OWJ. A MXI1-NUTM1 fusion protein with MYC-like activity suggests a novel oncogenic mechanism in a subset of NUTM1-rearranged tumors. J Transl Med 2021; 101:26-37. [PMID: 32873880 DOI: 10.1038/s41374-020-00484-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/10/2020] [Accepted: 08/17/2020] [Indexed: 12/21/2022] Open
Abstract
Most NUTM1-rearranged neoplasms (NRNs) have fusions between NUTM1 and BRD (bromodomain-containing) family members and are termed NUT carcinomas (NCs) because they show some squamous differentiation. However, some NRNs are associated with fusions between NUTM1 and members of the MAD (MAX dimerization) gene family of MYC antagonists. Here we describe a small round cell malignancy from the gastro-esophageal junction with a previously unreported fusion between NUTM1 and the MAD family member MXI1. In contrast to NCs, the MXI1-NUTM1 tumor did not show squamous differentiation and did not express MYC, TP63 or SOX2, genes known to be targets of BRD-NUTM1 proteins and critical for NC oncogenesis. Transcriptome analysis showed paradoxical enrichment of MYC target genes in the MXI1-NUTM1 tumor despite the lack of MYC expression. When expressed in vitro MXI1-NUTM1 partially phenocopied MYC, enhancing cell proliferation and cooperating with oncogenic HRAS to produce anchorage-independent cell growth. These data provide evidence that MAD family members, which are normally repressors of MYC activity, can be converted into MYC-like mimics by fusion to NUTM1. The pathological features and novel oncogenic mechanism of the MXI1-NUTM1 tumor show that identification of NUTM1 fusion partners can be important for accurate diagnostic classification of some NRN subtypes, and potentially may guide therapeutic options.
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Affiliation(s)
- Christopher R McEvoy
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Holly Holliday
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW, 2010, Australia
- Faculty of Medicine, St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, 2010, Australia
| | - Niko Thio
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Catherine Mitchell
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - David Y Choong
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Bhargavi Yellapu
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
- Epworth Healthcare, Melbourne, VIC, Australia
| | - Hui San Leong
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Huiling Xu
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Stephen Lade
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Judy Browning
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Elena A Takano
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - David J Byrne
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Anthony J Gill
- Cancer Diagnosis and Pathology Group, Kolling Institute of Medical Research, Royal North Shore Hospital, St Leonards, NSW, 2065, Australia
- NSW Health Pathology, Department of Anatomical Pathology, Royal North Shore Hospital, Sydney, NSW, 2065, Australia
- University of Sydney, Sydney, NSW, 2065, Australia
| | - Cuong P Duong
- Division of Cancer Surgery, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Jason Li
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Andrew P Fellowes
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
| | - Stephen B Fox
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia
- University of Melbourne, Parkville, VIC, 3010, Australia
| | - Alexander Swarbrick
- The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW, 2010, Australia
- Faculty of Medicine, St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, 2010, Australia
| | - Owen W J Prall
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, 3000, Australia.
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14
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The Molecular 'Myc-anisms' Behind Myc-Driven Tumorigenesis and the Relevant Myc-Directed Therapeutics. Int J Mol Sci 2020; 21:ijms21249486. [PMID: 33322239 PMCID: PMC7764474 DOI: 10.3390/ijms21249486] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/09/2020] [Accepted: 12/11/2020] [Indexed: 02/07/2023] Open
Abstract
MYC, a well-studied proto-oncogene that is overexpressed in >20% of tumors across all cancers, is classically known as “undruggable” due to its crucial roles in cell processes and its lack of a drug binding pocket. Four decades of research and creativity led to the discovery of a myriad of indirect (and now some direct!) therapeutic strategies targeting Myc. This review explores the various mechanisms in which Myc promotes cancer and highlights five key therapeutic approaches to disrupt Myc, including transcription, Myc-Max dimerization, protein stability, cell cycle regulation, and metabolism, in order to develop more specific Myc-directed therapies.
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15
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TRIB3 promotes MYC-associated lymphoma development through suppression of UBE3B-mediated MYC degradation. Nat Commun 2020; 11:6316. [PMID: 33298911 PMCID: PMC7725785 DOI: 10.1038/s41467-020-20107-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 11/10/2020] [Indexed: 12/31/2022] Open
Abstract
The transcription factor MYC is deregulated in almost all human cancers, especially in aggressive lymphomas, through chromosomal translocation, amplification, and transcription hyperactivation. Here, we report that high expression of tribbles homologue 3 (TRIB3) positively correlates with elevated MYC expression in lymphoma specimens; TRIB3 deletion attenuates the initiation and progression of MYC-driven lymphoma by reducing MYC expression. Mechanistically, TRIB3 interacts with MYC to suppress E3 ubiquitin ligase UBE3B-mediated MYC ubiquitination and degradation, which enhances MYC transcriptional activity, causing high proliferation and self-renewal of lymphoma cells. Use of a peptide to disturb the TRIB3-MYC interaction together with doxorubicin reduces the tumor burden in MycEμ mice and patient-derived xenografts. The pathophysiological relevance of UBE3B, TRIB3 and MYC is further demonstrated in human lymphoma. Our study highlights a key mechanism for controlling MYC expression and a potential therapeutic option for treating lymphomas with high TRIB3-MYC expression. c-MYC is often deregulated in human cancers including lymphomas. Here, the authors show that a member of the pseudokinase family, tribbles homologue 3 (TRIB3), interacts with c-MYC to suppress c-MYC ubiquitination and degradation, leading to increased proliferation and self-renewal of lymphoma cells.
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16
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Feng W, Dean DC, Hornicek FJ, Spentzos D, Hoffman RM, Shi H, Duan Z. Myc is a prognostic biomarker and potential therapeutic target in osteosarcoma. Ther Adv Med Oncol 2020; 12:1758835920922055. [PMID: 32426053 PMCID: PMC7222246 DOI: 10.1177/1758835920922055] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 04/03/2020] [Indexed: 12/14/2022] Open
Abstract
Background Over the past four decades, outcomes for osteosarcoma patients have plateaued as there have been few emerging therapies showing clinical results. Thus, the identification of novel biomarkers and therapeutic strategies are urgently needed to address these primary obstacles in patient care. Although the Myc-oncogene has known roles in oncogenesis and cancer cell growth, its expression and function in osteosarcoma are largely unknown. Methods Expression of Myc was determined by Western blotting of osteosarcoma cell lines and patient tissues, and by immunohistochemistry of a unique osteosarcoma tissue microarray (TMA) constructed from 70 patient samples with extensive follow-up data. Myc specific siRNA and inhibitor 10058-F4 were applied to examine the effect of Myc inhibition on osteosarcoma cell proliferation. The clonogenicity and migration activity was determined by clonogenic and wound-healing assays. A mimic in vivo assay, three-dimensional (3D) cell culture model, was performed to further validate the effect of Myc inhibition on osteosarcoma cell tumorigenic markers. Results Myc was significantly overexpressed in human osteosarcoma cell lines compared with normal human osteoblasts, and also highly expressed in fresh osteosarcoma tissues. Higher Myc expression correlated significantly with metastasis and poor prognosis. Through the addition of Myc specific siRNA and inhibitor, we significantly reduced Myc protein expression, resulting in decreased osteosarcoma cell proliferation. Inhibition of Myc also suppressed the migration, clonogenicity, and spheroid growth of osteosarcoma cells. Conclusion Our results support Myc as an emerging prognostic biomarker and therapeutic target in osteosarcoma therapy.
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Affiliation(s)
- Wenlong Feng
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Dylan C Dean
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Francis J Hornicek
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Dimitrios Spentzos
- Department of Orthopaedic Surgery, Musculoskeletal Oncology Service, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Robert M Hoffman
- AntiCancer Inc., San Diego, CA, USA Department of Surgery, University of California, San Diego, CA, USA
| | - Huirong Shi
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, 1 Jianshe East Road, Zhengzhou, Henan 450052, China
| | - Zhenfeng Duan
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, 615 Charles, E. Young. Dr. South, Los Angeles, CA 90095, USA
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17
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Hao D, Thomsen B, Bai J, Peng S, Lan X, Huang Y, Wang X, Chen H. Expression profiles of the MXD3 gene and association of sequence variants with growth traits in Xianan and Qinchuan cattle. Vet Med Sci 2020; 6:399-409. [PMID: 32141244 PMCID: PMC7397896 DOI: 10.1002/vms3.251] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 01/07/2020] [Accepted: 01/24/2020] [Indexed: 01/17/2023] Open
Abstract
Max dimerization protein 3 (MXD3) belongs to the MYC superfamily of basic helix‐loop‐helix leucine zipper transcription factors, and MXD3‐MAX heterodimers can bind to promoters of target genes to modulate their expression. The aim of this study was to determine the MXD3 mRNA expression levels in various cattle tissues comprising heart, liver, spleen, lung, kidney, Longissimus dorsi muscle and subcutaneous fat in Chinese Qinchuan and Xianan cattle breeds. The RT‐qPCR data showed that the MXD3 gene was variably expressed between all tissues and at levels that were significantly different between two breeds (p < .05). We used the polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) method to investigate the possible association between single‐nucleotide polymorphisms (SNP) within the MXD3 gene and five different growth traits in cattle. We found two intronic SNPs (g.2694 C>T and g.3801 T>C) and one SNP in 3′untranslated region (3′UTR) (g.6263 G>A) of MXD3 gene. Association analysis revealed strong associations between pairwise and triple SNP combinations and the growth traits. Based on these results, we suggest that MXD3 polymorphisms could be useful as molecular markers in the Chinese beef cattle breeding program.
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Affiliation(s)
- Dan Hao
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Animal Genetics, Breeding and Reproduction, Yangling, Shaanxi, China.,Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Bo Thomsen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Jiangsong Bai
- College of Veterinary Medicine, China Agricultural University, Beijing, China.,Beijing Zhongnongtongchuang (ZNTC) Biotechnology Co., Ltd, Beijing, China
| | - Shujun Peng
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Animal Genetics, Breeding and Reproduction, Yangling, Shaanxi, China
| | - Xianyong Lan
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Animal Genetics, Breeding and Reproduction, Yangling, Shaanxi, China
| | - Yongzhen Huang
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Animal Genetics, Breeding and Reproduction, Yangling, Shaanxi, China
| | - Xiao Wang
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Hong Chen
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Animal Genetics, Breeding and Reproduction, Yangling, Shaanxi, China
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18
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Kurbegovic A, Trudel M. The master regulators Myc and p53 cellular signaling and functions in polycystic kidney disease. Cell Signal 2020; 71:109594. [PMID: 32145315 DOI: 10.1016/j.cellsig.2020.109594] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 01/08/2023]
Abstract
The transcription factors Myc and p53 associated with oncogenesis play determinant roles in a human genetic disorder, autosomal dominant polycystic kidney disease (ADPKD), that was coined early in ADPKD etiology a «neoplasia in disguise ». These factors are interdependent master cell regulators of major biological processes including proliferation, apoptosis, cell growth, metabolism, inflammation, fibrosis and differentiation that are all modulated in ADPKD. Myc and p53 proteins evolved to respond and carry out overlapping functions via opposing mechanisms of action. Studies in human ADPKD kidneys, caused by mutations in the PKD1 or PKD2 genes, reveal reduced p53 expression and high expression of Myc in the cystic tubular epithelium. Myc and p53 via direct interaction act respectively, as transcriptional activator and repressor of PKD1 gene expression, consistent with increased renal PKD1 levels in ADPKD. Mouse models generated by Pkd1 and Pkd2 gene dosage dysregulation reproduce renal cystogenesis with activation of Myc expression and numerous signaling pathways, strikingly similar to those determined in human ADPKD. In fact, upregulation of renal Myc expression is also detected in virtually all non-orthologous animal models of PKD. A definitive causal connection of Myc with cystogenesis was established by renal overexpression of Myc in transgenic mice that phenocopies human ADPKD. The network of activated signaling pathways in human and mouse cystogenesis individually or in combination can target Myc as a central node of PKD pathogenesis. One or many of the multiple functions of Myc upon activation can play a role in every phases of ADPKD development and lend credence to the notion of "Myc addiction" for cystogenesis. We propose that the residual p53 levels are conducive to an ADPKD biological program without cancerogenesis while a "p53 dependent annihilation" mechanism would be permissive to oncogenesis. Of major importance, Myc ablation in orthologous mouse models or direct inhibition in non-orthologous mouse model significantly delays cystogenesis consistent with pharmacologic or genetic inhibition of Myc upstream regulator or downstream targets in the mouse. Together, these studies on PKD proteins upon dysregulation not only converged on Myc as a focal point but also attribute to Myc upregulation a causal and « driver » role in pathogenesis. This review will present and discuss our current knowledge on Myc and p53, focused on PKD mouse models and ADPKD.
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Affiliation(s)
- Almira Kurbegovic
- Institut de Recherches Cliniques de Montréal, Molecular Genetics and Development, Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Marie Trudel
- Institut de Recherches Cliniques de Montréal, Molecular Genetics and Development, Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada.
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19
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McEvoy CR, Fox SB, Prall OWJ. Emerging entities in NUTM1-rearranged neoplasms. Genes Chromosomes Cancer 2020; 59:375-385. [PMID: 32060986 DOI: 10.1002/gcc.22838] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 02/03/2020] [Accepted: 02/07/2020] [Indexed: 12/11/2022] Open
Abstract
Structural alterations of NUTM1 were originally thought to be restricted to poorly differentiated carcinomas with variable squamous differentiation originating in the midline organs of children and adolescents. Termed NUT carcinomas (NCs), they were defined by a t(15;19) chromosomal rearrangement that was found to result in a BRD4-NUTM1 gene fusion. However, the use of DNA and RNA-based next-generation sequencing has recently revealed a multitude of new NUTM1 fusion partners in a diverse array of neoplasms including sarcoma-like tumors, poromas, and acute lymphoblastic leukemias (ALLs) that we propose to call NUTM1-rearranged neoplasms (NRNs). Intriguingly, the nosology of NRNs often correlates with the functional classification of the fusion partner, suggesting different oncogenic mechanisms within each NRN division. Indeed, whereas NCs are characterized by their aggressiveness and intransigence to standard therapeutic measures, the more positive clinical outcomes seen in some sarcoma and ALL NRNs may reflect these mechanistic differences. Here we provide a broad overview of the molecular, nosological, and clinical features in these newly discovered neoplastic entities. We describe how aberrant expression of NUTM1 due to fusion with an N-terminal DNA/chromatin-binding protein can generate a potentially powerful chromatin modifier that can give rise to oncogenic transformation in numerous cellular contexts. We also conclude that classification, clinical behavior, and therapeutic options may be best defined by the NUTM1 fusion partner rather than by tumor morphology or immunohistochemical profile.
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Affiliation(s)
- Christopher R McEvoy
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Stephen B Fox
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Owen W J Prall
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
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20
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Momozane T, Fukui E, Funaki S, Fujii M, Kinehara Y, Ito E, Miyagawa S, Ohno Y, Sawa Y, Okumura M, Shintani Y. Efficient Differentiation of Mouse Induced Pluripotent Stem Cells into Alveolar Epithelium Type II with a BRD4 Inhibitor. Stem Cells Int 2019; 2019:1271682. [PMID: 31949433 PMCID: PMC6948319 DOI: 10.1155/2019/1271682] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 11/05/2019] [Accepted: 11/19/2019] [Indexed: 01/10/2023] Open
Abstract
Regenerative medicine has continued to progress for lung biology and lung diseases. Efforts have focused on a variety of different applications for pluripotent stem cells. Several groups have reported successful methods for inducing differentiation of induced pluripotent stem cells (iPSCs) into the airway epithelium such as alveolar epithelium type II (ATII). However, differentiation efficiency varies among reports and improvements are needed. In the present paper, we propose a novel method for elimination of residual undifferentiated murine iPSCs using JQ1, a potent inhibitor of bromodomain (BRD) and extraterminal domain (BET) family proteins, for efficient differentiation into ATII. First, the murine iPSC line 20D-17 was induced to differentiate into ATII over a period of 26 days (days 0-26) using previously reported embryoid body seeding and stepwise differentiation methods. mRNA expressions of differentiation markers including surfactant protein C (Sftpc) were confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR) results, and 17% of the cells were shown positive for prosurfactant protein C (proSPC) in flow cytometry analysis. Next, those cells were cultured three-dimensionally in Matrigel for an additional 14 days (days 26-40), during which JQ1 was added for 4 days (days 28-32) to remove residual undifferentiated iPSCs. As a result, on day 40, the mRNA expression level of Sftpc in the three-dimensional culture was maintained at the same level as on day 26 and shown to be further increased by the addition of JQ1, with 39% of the cells found to express proSPC, showing that differentiation efficiency could be further increased. Three-dimensional culture with BRD4 inhibition by JQ1 improved the differentiation induction efficiency to ATII by removing residual undifferentiated murine iPSCs during the differentiation induction process.
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Affiliation(s)
- Toru Momozane
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Eriko Fukui
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Soichiro Funaki
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Makoto Fujii
- Department of Mathematical Health Science, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yuhei Kinehara
- Department of Respiratory Medicine and Clinical Immunology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Emiko Ito
- Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shigeru Miyagawa
- Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yuko Ohno
- Department of Mathematical Health Science, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yoshiki Sawa
- Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Meinoshin Okumura
- Department of General Thoracic Surgery, National Hospital Organization Toneyama Hospital, Osaka, Japan
| | - Yasushi Shintani
- Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
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21
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Na HY, Choe JY, Shin SA, Kim HJ, Han JH, Kim HK, Oh SH, Kim JE. Characteristics of CD5-positive diffuse large B-cell lymphoma among Koreans: High incidence of BCL2 and MYC double-expressors. PLoS One 2019; 14:e0224247. [PMID: 31644584 PMCID: PMC6808439 DOI: 10.1371/journal.pone.0224247] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 10/08/2019] [Indexed: 12/14/2022] Open
Abstract
Aberrant expression of CD5 has been reported in 5-10% of diffuse large B-cell lymphomas (DLBCLs). CD5+ DLBCL had been recognized as an aggressive immunophenotypic subgroup of DLBCL in the 2008 WHO classification of haematolymphoid neoplasm; however, it was eliminated from the list of subgroups of DLBCLs in the revised 2016 classification. Nevertheless, there is much controversy regarding the clinical significance of CD5 expression, and many researchers still assert that this subgroup exhibits an extremely unfavorable prognosis with frequent treatment failure. We retrospectively investigated 405 DLBCLs recruited from three university hospitals in Korea from 1997 to 2013. The clinical profile, immunophenotype, and chromosomal structural alterations of the BCL2 and MYC genes were compared according to CD5 expression. A total of 29 cases of de novo CD5+ DLBCL were identified out of 405 in our series (7.4%). Clinicopathologic correlation was performed in all 29 CD5+ DLBCLs and 166 CD5- DLBCLs which were eligible for full clinical review and further pathologic examination. Compared with CD5- counterparts, CD5+ DLBCLs showed female preponderance, frequent bone marrow involvement, higher lactate dehydrogenase level, advanced Ann Arbor stages and poorer prognosis (all p<0.05). Pathologically, the expression of CD5 positively correlated with that of BCL2, MYC and Ki-67 (all p<0.05). Coexpression of BCL2 and MYC, which is referred to as a double-expressor, was relatively more common in CD5+ DLBCL, whereas translocation or amplification of these genes was very rare. in conclusion, the expression of CD5 is an independent poor prognostic factor of DLBCLs, and this subgroup displays unique clinicopathologic features. Although the exact mechanism remains uncertain, consistent activation of BCL2 and MYC by alternative pathways other than chromosomal translocation may contribute to the pathogenesis.
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MESH Headings
- Aged
- CD5 Antigens/metabolism
- Female
- Gene Amplification
- Gene Expression Regulation, Neoplastic
- Humans
- Lymphoma, Large B-Cell, Diffuse/epidemiology
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/metabolism
- Lymphoma, Large B-Cell, Diffuse/pathology
- Male
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-myc/genetics
- Republic of Korea/epidemiology
- Retrospective Studies
- Translocation, Genetic
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Affiliation(s)
- Hee Young Na
- Department of Pathology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
- Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ji-Young Choe
- Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Pathology, Hallym University Sacred Heart Hospital, Anyang, Gyeonggi, Republic of Korea
| | - Sun Ah Shin
- Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Pathology, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hyun-Jung Kim
- Department of Pathology, Inje University Sanggye Paik Hospital, Seoul, Republic of Korea
| | - Jae Ho Han
- Department of Pathology, Ajou University School of Medicine, Suwon, Geonggi, Republic of Korea
| | - Hee Kyung Kim
- Department of Pathology, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea
| | - So Hee Oh
- Department of Biostatistics, Seoul National University Seoul Metropolitan Government Boramae Medical Center, Seoul, Republic of Korea
| | - Ji Eun Kim
- Department of Pathology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Pathology, Seoul National University Seoul Metropolitan Government Boramae Medical Center, Seoul, Republic of Korea
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22
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Zhernovkov V, Santra T, Cassidy H, Rukhlenko O, Matallanas D, Krstic A, Kolch W, Lobaskin V, Kholodenko BN. An integrative computational approach for a prioritization of key transcription regulators associated with nanomaterial-induced toxicity. Toxicol Sci 2019; 171:303-314. [PMID: 31271423 DOI: 10.1093/toxsci/kfz151] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 06/27/2019] [Accepted: 06/28/2019] [Indexed: 12/19/2022] Open
Abstract
A rapid increase of new nanomaterial products poses new challenges for their risk assessment. Current traditional methods for estimating potential adverse health effect of nanomaterials (NMs) are complex, time consuming and expensive. In order to develop new prediction tests for nanotoxicity evaluation, a systems biology approach and data from high-throughput omics experiments can be used. We present a computational approach that combines reverse engineering techniques, network analysis and pathway enrichment analysis for inferring the transcriptional regulation landscape and its functional interpretation. To illustrate this approach, we used published transcriptomic data derived from mice lung tissue exposed to carbon nanotubes (NM-401 and NRCWE-26). Because fibrosis is the most common adverse effect of these NMs, we included in our analysis the data for bleomycin (BLM) treatment, which is a well-known fibrosis inducer. We inferred gene regulatory networks for each NM and BLM to capture functional hierarchical regulatory structures between genes and their regulators. Despite the different nature of the lung injury caused by nanoparticles and BLM, we identified several conserved core regulators for all agents. We reason that these regulators can be considered as early predictors of toxic responses after NMs exposure. This integrative approach, which refines traditional methods of transcriptomic analysis, can be useful for prioritization of potential core regulators and generation of new hypothesis about mechanisms of nanoparticles toxicity.
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Affiliation(s)
- Vadim Zhernovkov
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland
| | - Tapesh Santra
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland
| | - Hilary Cassidy
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland
| | - Oleksii Rukhlenko
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland
| | - David Matallanas
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland.,School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Aleksandar Krstic
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland
| | - Walter Kolch
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland.,School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland.,Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Ireland
| | | | - Boris N Kholodenko
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland.,School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland.,Conway Institute of Biomolecular & Biomedical Research, University College Dublin, Ireland.,Department of Pharmacology, Yale University School of Medicine, New Haven CT, USA
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23
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Hematopoietic stem and progenitor cell proliferation and differentiation requires the trithorax protein Ash2l. Sci Rep 2019; 9:8262. [PMID: 31164666 PMCID: PMC6547667 DOI: 10.1038/s41598-019-44720-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 05/20/2019] [Indexed: 12/18/2022] Open
Abstract
Post-translational modifications of core histones participate in controlling the expression of genes. Methylation of lysine 4 of histone H3 (H3K4), together with acetylation of H3K27, is closely associated with open chromatin and gene transcription. H3K4 methylation is catalyzed by KMT2 lysine methyltransferases that include the mixed-lineage leukemia 1–4 (MLL1-4) and SET1A and B enzymes. For efficient catalysis, all six require a core complex of four proteins, WDR5, RBBP5, ASH2L, and DPY30. We report that targeted disruption of Ash2l in the murine hematopoietic system results in the death of the mice due to a rapid loss of mature hematopoietic cells. However, lin−Sca1+Kit+ (LSK) cells, which are highly enriched in hematopoietic stem and multi-potent progenitor cells, accumulated in the bone marrow. The loss of Ash2l resulted in global reduction of H3K4 methylation and deregulated gene expression, including down-regulation of many mitosis-associated genes. As a consequence, LSK cells accumulated in the G2-phase of the cell cycle and were unable to proliferate and differentiate. In conclusion, Ash2l is essential for balanced gene expression and for hematopoietic stem and multi-potent progenitor cell physiology.
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24
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García-Gutiérrez L, Delgado MD, León J. MYC Oncogene Contributions to Release of Cell Cycle Brakes. Genes (Basel) 2019; 10:E244. [PMID: 30909496 PMCID: PMC6470592 DOI: 10.3390/genes10030244] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 03/16/2019] [Accepted: 03/18/2019] [Indexed: 12/12/2022] Open
Abstract
Promotion of the cell cycle is a major oncogenic mechanism of the oncogene c-MYC (MYC). MYC promotes the cell cycle by not only activating or inducing cyclins and CDKs but also through the downregulation or the impairment of the activity of a set of proteins that act as cell-cycle brakes. This review is focused on the role of MYC as a cell-cycle brake releaser i.e., how MYC stimulates the cell cycle mainly through the functional inactivation of cell cycle inhibitors. MYC antagonizes the activities and/or the expression levels of p15, ARF, p21, and p27. The mechanism involved differs for each protein. p15 (encoded by CDKN2B) and p21 (CDKN1A) are repressed by MYC at the transcriptional level. In contrast, MYC activates ARF, which contributes to the apoptosis induced by high MYC levels. At least in some cells types, MYC inhibits the transcription of the p27 gene (CDKN1B) but also enhances p27's degradation through the upregulation of components of ubiquitin ligases complexes. The effect of MYC on cell-cycle brakes also opens the possibility of antitumoral therapies based on synthetic lethal interactions involving MYC and CDKs, for which a series of inhibitors are being developed and tested in clinical trials.
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Affiliation(s)
- Lucía García-Gutiérrez
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC) CSIC-Universidad de Cantabria and Department of Biología Molecular, Universidad de Cantabria, 39011 Santander, Spain.
- Current address: Systems Biology Ireland, University College Dublin, Belfield, Dublin 4, Ireland.
| | - María Dolores Delgado
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC) CSIC-Universidad de Cantabria and Department of Biología Molecular, Universidad de Cantabria, 39011 Santander, Spain.
| | - Javier León
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC) CSIC-Universidad de Cantabria and Department of Biología Molecular, Universidad de Cantabria, 39011 Santander, Spain.
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25
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Liu Y, Liu D, Wan W. MYCN-induced E2F5 promotes neuroblastoma cell proliferation through regulating cell cycle progression. Biochem Biophys Res Commun 2019; 511:35-40. [DOI: 10.1016/j.bbrc.2019.01.087] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 01/19/2019] [Indexed: 01/06/2023]
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26
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Ohanian M, Rozovski U, Kanagal-Shamanna R, Abruzzo LV, Loghavi S, Kadia T, Futreal A, Bhalla K, Zuo Z, Huh YO, Post SM, Ruvolo P, Garcia-Manero G, Andreeff M, Kornblau S, Borthakur G, Hu P, Medeiros LJ, Takahashi K, Hornbaker MJ, Zhang J, Nogueras-González GM, Huang X, Verstovsek S, Estrov Z, Pierce S, Ravandi F, Kantarjian HM, Bueso-Ramos CE, Cortes JE. MYC protein expression is an important prognostic factor in acute myeloid leukemia. Leuk Lymphoma 2019; 60:37-48. [PMID: 29741984 PMCID: PMC6226369 DOI: 10.1080/10428194.2018.1464158] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
As new drugs targeting MYC show clinical activity in acute myeloid leukemia (AML), understanding MYC expression in AML is of critical importance. We assessed MYC protein expression by immunohistochemistry in bone marrow of patients with untreated AML (n = 265). Overall, 90% of patients demonstrated MYC overexpression and MYC immunopositivity ≤6% was associated with superior complete remission (CR) duration of 23 months versus 12 months for MYC immunopositivity >6% (p = .028). Among 241 patients at higher risk for relapse, including those ≥55 years of age and patients with intermediate- and high-risk AML, MYC immunopositivity ≤6% conferred significantly superior median overall survival (OS) (24 versus 13 months; p = .042), event-free survival (EFS) (14 versus 6 months; p = .048), and relapse-free survival (RFS) (25 versus 12 months; p = .024). The prognostic impact of MYC-immunopositivity was retained on multivariate analysis of OS, EFS, and RFS. We conclude that MYC immunopositivity is an important prognostic factor in patients with untreated AML, particularly those at higher risk for relapse.
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Affiliation(s)
- Maro Ohanian
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Uri Rozovski
- Department of Hematology, Davidoff Cancer Center at Rabin Medical Center, Sackler School of Medicine, Tel Aviv University, Israel
| | - Rashmi Kanagal-Shamanna
- Department of Hematopathology, The University of Texas at MD Anderson Cancer Center Houston, Texas
| | - Lynne V. Abruzzo
- Department of Pathology, Ohio State University, Columbus, OH 43202
| | - Sanam Loghavi
- Department of Hematopathology, The University of Texas at MD Anderson Cancer Center Houston, Texas
| | - Tapan Kadia
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Andrew Futreal
- Department of Genomic Medicine, The University of Texas at MD Anderson Cancer Center, Houston, TX
| | - Kapil Bhalla
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Zhuang Zuo
- Department of Hematopathology, The University of Texas at MD Anderson Cancer Center Houston, Texas
| | - Yang O. Huh
- Department of Hematopathology, The University of Texas at MD Anderson Cancer Center Houston, Texas
| | - Sean M. Post
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Peter Ruvolo
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Guillermo Garcia-Manero
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Michael Andreeff
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Steven Kornblau
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Gautam Borthakur
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Peter Hu
- School of Health Professions, The University of Texas at MD Anderson Cancer Center, Houston, TX
| | - L. Jeffrey Medeiros
- Department of Hematopathology, The University of Texas at MD Anderson Cancer Center Houston, Texas
| | - Koichi Takahashi
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Marisa J. Hornbaker
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Jianhua Zhang
- Department of Genomic Medicine, The University of Texas at MD Anderson Cancer Center, Houston, TX
| | | | - Xuelin Huang
- Department of Biostatistics, The University of Texas at MD Anderson Cancer Center, Houston, TX
| | - Srdan Verstovsek
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Zeev Estrov
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Sherry Pierce
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Farhad Ravandi
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Hagop M. Kantarjian
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
| | - Carlos E. Bueso-Ramos
- Department of Hematopathology, The University of Texas at MD Anderson Cancer Center Houston, Texas
| | - Jorge E. Cortes
- Department of Leukemia, The University of Texas at MD Anderson Cancer Center, Houston, Texas
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27
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Nakagawa T, Yoneda M, Higashi M, Ohkuma Y, Ito T. Enhancer function regulated by combinations of transcription factors and cofactors. Genes Cells 2018; 23:808-821. [PMID: 30092612 DOI: 10.1111/gtc.12634] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 12/11/2022]
Abstract
Regulation of the expression of diverse genes is essential for making possible the complexity of higher organisms, and the temporal and spatial regulation of gene expression allows for the alteration of cell types and growth patterns. A critical component of this regulation is the DNA sequence-specific binding of transcription factors (TFs). However, most TFs do not independently participate in gene transcriptional regulation, because they lack an effector function. Instead, TFs are thought to work by recruiting cofactors, including Mediator complex (Mediator), chromatin-remodeling complexes (CRCs), and histone-modifying complexes (HMCs). Mediator associates with the majority of transcribed genes and acts as an integrator of multiple signals. On the other hand, CRCs and HMCs are selectively recruited by TFs. Although all the pairings between TFs and CRCs or HMCs are not fully known, there are a growing number of established TF-CRC and TF-HMC combinations. In this review, we focused on the most important of these pairings and discuss how they control gene expression.
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Affiliation(s)
- Takeya Nakagawa
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, Japan
| | - Mitsuhiro Yoneda
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, Japan
| | - Miki Higashi
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, Japan
| | - Yoshiaki Ohkuma
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, Japan
| | - Takashi Ito
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, Japan
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28
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Dingar D, Tu WB, Resetca D, Lourenco C, Tamachi A, De Melo J, Houlahan KE, Kalkat M, Chan PK, Boutros PC, Raught B, Penn LZ. MYC dephosphorylation by the PP1/PNUTS phosphatase complex regulates chromatin binding and protein stability. Nat Commun 2018; 9:3502. [PMID: 30158517 PMCID: PMC6115416 DOI: 10.1038/s41467-018-05660-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 07/06/2018] [Indexed: 01/08/2023] Open
Abstract
The c-MYC (MYC) oncoprotein is deregulated in over 50% of cancers, yet regulatory mechanisms controlling MYC remain unclear. To this end, we interrogated the MYC interactome using BioID mass spectrometry (MS) and identified PP1 (protein phosphatase 1) and its regulatory subunit PNUTS (protein phosphatase-1 nuclear-targeting subunit) as MYC interactors. We demonstrate that endogenous MYC and PNUTS interact across multiple cell types and that they co-occupy MYC target gene promoters. Inhibiting PP1 by RNAi or pharmacological inhibition results in MYC hyperphosphorylation at multiple serine and threonine residues, leading to a decrease in MYC protein levels due to proteasomal degradation through the canonical SCFFBXW7 pathway. MYC hyperphosphorylation can be rescued specifically with exogenous PP1, but not other phosphatases. Hyperphosphorylated MYC retained interaction with its transcriptional partner MAX, but binding to chromatin is significantly compromised. Our work demonstrates that PP1/PNUTS stabilizes chromatin-bound MYC in proliferating cells. Deregulated MYC activity is oncogenic and is deregulated in a large fraction of human cancers. Here the authors find that protein phosphatase 1 and its regulatory subunit PNUTS controls MYC stability and its interaction with chromatin.
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Affiliation(s)
- Dharmendra Dingar
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada
| | - William B Tu
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada
| | - Diana Resetca
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada
| | - Corey Lourenco
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada
| | - Aaliya Tamachi
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada
| | - Jason De Melo
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada
| | - Kathleen E Houlahan
- Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada.,Ontario Institute for Cancer Research, Toronto, ON Canada M5G 0A3, Canada
| | - Manpreet Kalkat
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada
| | - Pak-Kei Chan
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada
| | - Paul C Boutros
- Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada.,Ontario Institute for Cancer Research, Toronto, ON Canada M5G 0A3, Canada.,Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada M5S 1A8, Canada
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada
| | - Linda Z Penn
- Princess Margaret Cancer Centre, University Health Network, Toronto, M5G 1L7, ON, Canada. .,Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, Canada.
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29
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Schaub FX, Dhankani V, Berger AC, Trivedi M, Richardson AB, Shaw R, Zhao W, Zhang X, Ventura A, Liu Y, Ayer DE, Hurlin PJ, Cherniack AD, Eisenman RN, Bernard B, Grandori C. Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas. Cell Syst 2018; 6:282-300.e2. [PMID: 29596783 PMCID: PMC5892207 DOI: 10.1016/j.cels.2018.03.003] [Citation(s) in RCA: 233] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 02/06/2018] [Accepted: 03/02/2018] [Indexed: 12/19/2022]
Abstract
Although the MYC oncogene has been implicated in cancer, a systematic assessment of alterations of MYC, related transcription factors, and co-regulatory proteins, forming the proximal MYC network (PMN), across human cancers is lacking. Using computational approaches, we define genomic and proteomic features associated with MYC and the PMN across the 33 cancers of The Cancer Genome Atlas. Pan-cancer, 28% of all samples had at least one of the MYC paralogs amplified. In contrast, the MYC antagonists MGA and MNT were the most frequently mutated or deleted members, proposing a role as tumor suppressors. MYC alterations were mutually exclusive with PIK3CA, PTEN, APC, or BRAF alterations, suggesting that MYC is a distinct oncogenic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such as immune response and growth factor signaling; chromatin, translation, and DNA replication/repair were conserved pan-cancer. This analysis reveals insights into MYC biology and is a reference for biomarkers and therapeutics for cancers with alterations of MYC or the PMN.
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Affiliation(s)
- Franz X Schaub
- Cure First, Seattle, WA, USA; SEngine Precision Medicine, Seattle, WA, USA
| | | | - Ashton C Berger
- The Eli and Edythe L. Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
| | | | | | - Reid Shaw
- SEngine Precision Medicine, Seattle, WA, USA
| | - Wei Zhao
- Department of Systems Biology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Xiaoyang Zhang
- Dana-Farber Cancer Institute, the Broad Institute of Harvard and MIT, and Harvard Medical School, Boston, MA, USA
| | - Andrea Ventura
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Yuexin Liu
- Department of Systems Biology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Donald E Ayer
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Peter J Hurlin
- Shriners Hospitals for Children Research Center, Department of Cell, Developmental and Cancer Biology, Oregon Health & Science University, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, USA
| | - Andrew D Cherniack
- Dana-Farber Cancer Institute, the Broad Institute of Harvard and MIT, and Harvard Medical School, Boston, MA, USA
| | - Robert N Eisenman
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Brady Bernard
- Institute for Systems Biology, Seattle, WA, USA; Providence Health and Services, Portland, OR, USA.
| | - Carla Grandori
- Cure First, Seattle, WA, USA; SEngine Precision Medicine, Seattle, WA, USA.
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30
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He D, Guo X, Zhang E, Zi F, Chen J, Chen Q, Lin X, Yang L, Li Y, Wu W, Yang Y, He J, Cai Z. Quercetin induces cell apoptosis of myeloma and displays a synergistic effect with dexamethasone in vitro and in vivo xenograft models. Oncotarget 2018; 7:45489-45499. [PMID: 27329589 PMCID: PMC5216736 DOI: 10.18632/oncotarget.9993] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 05/28/2016] [Indexed: 12/01/2022] Open
Abstract
Quercetin, a kind of dietary flavonoid, has shown its anticancer activity in many kinds of cancers including hematological malignancies (acute myelogenous leukemia, chronic myelogenous leukemia, chronic lymphocytic leukemia, and MM) in vitro and in vivo. However, its effects on MM need further investigation. In this study, MM cell lines were treated with quercetin alone or in combination with dexamethasone. In order to observe the effects in vivo, a xenograft model of human myeloma was established. Quercetin inhibited proliferation of MM cells (RPMI8226, ARP-1, and MM.1R) by inducing cell cycle arrest in the G2/M phase and apoptosis. Western blot showed that quercetin downregulated c-myc expression and upregulated p21 expression. Quercetin also activated caspase-3, caspase-9, and poly(ADP-ribose)polymerase 1. Caspase inhibitors partially blocked apoptosis induced by quercetin. Furthermore, quercetin combined with dexamethasone significantly increased MM cell apoptosis. In vivo xenograft models, quercetin obviously inhibited tumor growth. Caspase-3 was activated to a greater extent when quercetin was combined with dexamethasone. In conclusion, quercetin alone or in combination with dexamethasone may be an effective therapy for MM.
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Affiliation(s)
- Donghua He
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xing Guo
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Enfan Zhang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Fuming Zi
- Department of Hematology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Jing Chen
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Qingxiao Chen
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xuanru Lin
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Li Yang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yi Li
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Wenjun Wu
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yang Yang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jingsong He
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhen Cai
- Bone Marrow Transplantation Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
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31
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Yu Z, Li T, Wang C, Deng S, Zhang B, Huo X, Zhang B, Wang X, Zhong Y, Ma X. Gamabufotalin triggers c-Myc degradation via induction of WWP2 in multiple myeloma cells. Oncotarget 2017; 7:15725-37. [PMID: 26894970 PMCID: PMC4941272 DOI: 10.18632/oncotarget.7398] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/05/2016] [Indexed: 12/14/2022] Open
Abstract
Deciding appropriate therapy for multiple myeloma (MM) is challenging because of the occurrence of multiple chromosomal changes and the fatal nature of the disease. In the current study, gamabufotalin (GBT) was isolated from toad venom, and its tumor-specific cytotoxicity was investigated in human MM cells. We found GBT inhibited cell growth and induced apoptosis with the IC50 values <50 nM. Mechanistic studies using functional approaches identified GBT as an inhibitor of c-Myc. Further analysis showed that GBT especially evoked the ubiquitination and degradation of c-Myc protein, thereby globally repressing the expression of c-Myc target genes. GBT treatment inhibited ERK and AKT signals, while stimulating the activation of JNK cascade. An E3 ubiquitin-protein ligase, WWP2, was upregulated following JNK activation and played an important role in c-Myc ubiquitination and degradation through direct protein-protein interaction. The antitumor effect of GBT was validated in a xenograft mouse model and the suppression of MM-induced osteolysis was verified in a SCID-hu model in vivo. Taken together, our study identified the potential of GBT as a promising therapeutic agent in the treatment of MM.
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Affiliation(s)
- Zhenlong Yu
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Tao Li
- Department of Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Zhejiang, China
| | - Chao Wang
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Sa Deng
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Baojing Zhang
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Xiaokui Huo
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Bo Zhang
- Department of Neurosurgery, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Xiaobo Wang
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Yuping Zhong
- Department of Hematology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Xiaochi Ma
- College of Pharmacy, Academy of Integrative Medicine, Dalian Medical University, Dalian, China
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32
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Yoshida M, Murata T, Ashio K, Narita Y, Watanabe T, Masud HMAA, Sato Y, Goshima F, Kimura H. Characterization of a Suppressive Cis-acting Element in the Epstein-Barr Virus LMP1 Promoter. Front Microbiol 2017; 8:2302. [PMID: 29213259 PMCID: PMC5702780 DOI: 10.3389/fmicb.2017.02302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/08/2017] [Indexed: 01/08/2023] Open
Abstract
Latent membrane protein 1 (LMP1) is a major oncogene encoded by Epstein–Barr virus (EBV) and is essential for immortalization of B cells by the virus. Previous studies suggested that several transcription factors, such as PU.1, RBP-Jκ, NFκB, EBF1, AP-2 and STAT, are involved in LMP1 induction; however, the means by which the oncogene is negatively regulated remains unclear. Here, we introduced short mutations into the proximal LMP1 promoter that includes recognition sites for the E-box and Ikaros transcription factors in the context of EBV-bacterial artificial chromosome. Upon infection, the mutant exhibited increased LMP1 expression and EBV-mediated immortalization of B cells. However, single mutations of either the E-box or Ikaros sites had limited effects on LMP1 expression and transformation. Our results suggest that this region contains a suppressive cis-regulatory element, but other transcriptional repressors (apart from the E-box and Ikaros transcription factors) may remain to be discovered.
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Affiliation(s)
- Masahiro Yoshida
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Takayuki Murata
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Japan
| | - Keiji Ashio
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yohei Narita
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Takahiro Watanabe
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - H M Abdullah Al Masud
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yoshitaka Sato
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Fumi Goshima
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroshi Kimura
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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33
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Human telomerase reverse transcriptase (hTERT) promotes gastric cancer invasion through cooperating with c-Myc to upregulate heparanase expression. Oncotarget 2017; 7:11364-79. [PMID: 26689987 PMCID: PMC4905479 DOI: 10.18632/oncotarget.6575] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 11/25/2015] [Indexed: 02/07/2023] Open
Abstract
Human telomerase reverse transcriptase (hTERT) is a central regulator of multiple hallmarks of tumors. However, the potential roles of hTERT in tumor invasion and metastasis and the underlying molecular mechanisms remain poorly understood. Here, we found that the expression of hTERT in gastric cancer (GC) was significantly associated with an advanced TNM stage, lymphatic metastasis. Survival analysis identified hTERT as an independent prognostic factor for survival of GC patients. hTERT promoted the invasion and metastasis of GC cells by binding to c-Myc and recruiting the complex to heparanase promoter to upregulate heparanase expression. In addition, our data demonstrated that hTERT activated Wnt/β-catenin signaling to promote c-Myc expression which could in turn activate hTERT transcription and expression, suggesting a positive feedback regulation in GC progression. Consistently, c-Myc and heparanase expression was positively correlated with hTERT levels, and was also an independent predictor of metastasis and survival. Collectively, our data provide a novel molecular mechanism for hTERT in promotion of GC invasion and metastasis, and highlight the molecular etiology and clinical significance of hTERT in GC progression. Targeting hTERT may represent a new therapeutic strategy to improve therapy and survival of GC patients.
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34
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Lüscher B, Bütepage M, Eckei L, Krieg S, Verheugd P, Shilton BH. ADP-Ribosylation, a Multifaceted Posttranslational Modification Involved in the Control of Cell Physiology in Health and Disease. Chem Rev 2017; 118:1092-1136. [PMID: 29172462 DOI: 10.1021/acs.chemrev.7b00122] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Posttranslational modifications (PTMs) regulate protein functions and interactions. ADP-ribosylation is a PTM, in which ADP-ribosyltransferases use nicotinamide adenine dinucleotide (NAD+) to modify target proteins with ADP-ribose. This modification can occur as mono- or poly-ADP-ribosylation. The latter involves the synthesis of long ADP-ribose chains that have specific properties due to the nature of the polymer. ADP-Ribosylation is reversed by hydrolases that cleave the glycosidic bonds either between ADP-ribose units or between the protein proximal ADP-ribose and a given amino acid side chain. Here we discuss the properties of the different enzymes associated with ADP-ribosylation and the consequences of this PTM on substrates. Furthermore, the different domains that interpret either mono- or poly-ADP-ribosylation and the implications for cellular processes are described.
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Affiliation(s)
- Bernhard Lüscher
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University , 52057 Aachen, Germany
| | - Mareike Bütepage
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University , 52057 Aachen, Germany
| | - Laura Eckei
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University , 52057 Aachen, Germany
| | - Sarah Krieg
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University , 52057 Aachen, Germany
| | - Patricia Verheugd
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University , 52057 Aachen, Germany
| | - Brian H Shilton
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University , 52057 Aachen, Germany.,Department of Biochemistry, Schulich School of Medicine & Dentistry, The University of Western Ontario , Medical Sciences Building Room 332, London, Ontario Canada N6A 5C1
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35
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Maldonado LY, Arsene D, Mato JM, Lu SC. Methionine adenosyltransferases in cancers: Mechanisms of dysregulation and implications for therapy. Exp Biol Med (Maywood) 2017; 243:107-117. [PMID: 29141455 DOI: 10.1177/1535370217740860] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Methionine adenosyltransferase genes encode enzymes responsible for the biosynthesis of S-adenosylmethionine, the principal biological methyl donor and precursor of polyamines and glutathione. Mammalian cells express three genes - MAT1A, MAT2A, and MAT2B - with distinct expression and functions. MAT1A is mainly expressed in the liver and maintains the differentiated states of both hepatocytes and bile duct epithelial cells. Conversely, MAT2A and MAT2B are widely distributed in non-parenchymal cells of the liver and extrahepatic tissues. Increasing evidence suggests that methionine adenosyltransferases play significant roles in the development of cancers. Liver cancers, namely hepatocellular carcinoma and cholangiocarcinoma, involve dysregulation of all three methionine adenosyltransferase genes. MAT1A reduction is associated with increased oxidative stress, progenitor cell expansion, genomic instability, and other mechanisms implicated in tumorigenesis. MAT2A/MAT2B induction confers growth and survival advantage to cancerous cells, enhancing tumor migration. Highlighted examples from colon, gastric, breast, pancreas and prostate cancer studies further underscore methionine adenosyltransferase genes' role beyond the liver in cancer development. In this subset of extra-hepatic cancers, MAT2A and MAT2B are induced via different regulatory mechanisms. Understanding the role of methionine adenosyltransferase genes in tumorigenesis helps identify attributes of these genes that may serve as valuable targets for therapy. While S-adenosylmethionine, and its metabolite, methylthioadenosine, have been largely explored as therapeutic interventions, targets aimed at regulation of MAT gene expression and methionine adenosyltransferase protein-protein interactions are now surfacing as potential effective strategies for treatment and chemoprevention of cancers. Impact statement This review examines the role of methionine adenosyltransferases (MATs) in human cancer development, with a particular focus on liver cancers in which all three MAT genes are implicated in tumorigenesis. An overview of MAT genes, isoenzymes and their regulation provide context for understanding consequences of dysregulation. Highlighting examples from liver, colon, gastric, breast, pancreas and prostate cancers underscore the importance of understanding MAT's tumorigenic role in identifying future targets for cancer therapy.
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Affiliation(s)
- Lauren Y Maldonado
- 1 Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Diana Arsene
- 2 Division of Gastroenterology and Hepatology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - José M Mato
- 3 CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (Ciberehd), Technology, Derio, Bizkaia 48160, Spain
| | - Shelly C Lu
- 4 Division of Digestive and Liver Diseases, 22494 Cedars-Sinai Medical Center , Cedars-Sinai Medical Center, LA, CA 90048, USA
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36
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The MXL-3/SBP-1 Axis Is Responsible for Glucose-Dependent Fat Accumulation in C. elegans. Genes (Basel) 2017; 8:genes8110307. [PMID: 29113111 PMCID: PMC5704220 DOI: 10.3390/genes8110307] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 10/31/2017] [Accepted: 10/31/2017] [Indexed: 12/26/2022] Open
Abstract
Chronic exposure to elevated glucose levels leads to fatty acid accumulation, which promotes the development of metabolic diseases such as obesity and type 2 diabetes. MXL-3 is a conserved transcriptional factor that modulates the inhibition of lipolysis in Caenorhabditis elegans. However, the role of MXL-3 in lipid metabolism during nutrient excess remains unknown. We hypothesized that inhibition of MXL-3 prevents glucose-dependent fat accumulation. Nematodes from wild-type N2, MXL-3::GFP and sbp-1 or mxl-3 null strains were grown on standard, high glucose or high glucose plus metformin plates for 24 h. Using laser-scanning confocal microscopy, we monitored the glucose-induced activation of MXL-3 labeled with GFP (MXL-3::GFP). Lipid levels were determined by Oil Red O (ORO) staining and gas chromatography/mass spectrometry, and gene expression was assessed by qRT-PCR. We found that high glucose activated MXL-3 by increasing its rate of nuclear entry, which in turn increased lipid levels via sterol regulatory element-binding protein (SBP-1). This activated critical genes that synthesize long chain unsaturated fatty acids (MUFAs and PUFAs) and repress lipolytic genes. Interestingly, the anti-diabetic drug metformin inhibited MXL-3 activation and subsequently prevented glucose-dependent fat accumulation. These findings highlight the importance of the MXL-3/SBP-1 axis in the regulation of lipid metabolism during nutritional excess and provide new insight into the mechanism by which metformin prevents lipid accumulation. This study also suggests that inhibition of MXL-3 may serve as a potential target for the treatment of chronic metabolic diseases, including obesity, type 2 diabetes, and cardiovascular disease.
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37
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PAF1 complex component Leo1 helps recruit Drosophila Myc to promoters. Proc Natl Acad Sci U S A 2017; 114:E9224-E9232. [PMID: 29078288 DOI: 10.1073/pnas.1705816114] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Myc oncogene is a transcription factor with a powerful grip on cellular growth and proliferation. The physical interaction of Myc with the E-box DNA motif has been extensively characterized, but it is less clear whether this sequence-specific interaction is sufficient for Myc's binding to its transcriptional targets. Here we identify the PAF1 complex, and specifically its component Leo1, as a factor that helps recruit Myc to target genes. Since the PAF1 complex is typically associated with active genes, this interaction with Leo1 contributes to Myc targeting to open promoters.
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38
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Myc target gene, long intergenic noncoding RNA, Linc00176 in hepatocellular carcinoma regulates cell cycle and cell survival by titrating tumor suppressor microRNAs. Oncogene 2017; 37:75-85. [DOI: 10.1038/onc.2017.312] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 07/25/2017] [Accepted: 07/28/2017] [Indexed: 12/12/2022]
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39
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Hypoxia-induced suppression of c-Myc by HIF-2α in human pulmonary endothelial cells attenuates TFAM expression. Cell Signal 2017; 38:230-237. [PMID: 28709643 DOI: 10.1016/j.cellsig.2017.07.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 07/03/2017] [Accepted: 07/10/2017] [Indexed: 01/26/2023]
Abstract
The adaptive response to hypoxia is mediated in large part by stabilization of the hypoxia-inducible factors, HIF-1α and HIF-2α. A hallmark of this response is the metabolic shift to decreased oxidative phosphorylation and increased glycolysis. We hypothesized that hypoxic responses would include a suppression of mitochondrial gene expression. We determined the effects of hypoxia on TFAM, a key mitochondrial transcription factor, in normal pulmonary artery endothelial cells. Hypoxia decreased gene expression of TFAM and that of its upstream regulator, the transcriptional co-activator PGC1β. Although HIF-1α and HIF-2α pathways both contributed to hypoxia-mediated PGC1β suppression, TFAM suppression was regulated solely by HIF-2α-dependent mechanisms. We found that HIF-2α suppresses TFAM by decreasing c-Myc expression. In addition, we show a role for c-Jun in this pathway, linking HIF-2α with attenuation of c-Jun activation. Taken together, these findings establish a new link between HIF-2α and MAPK-signaling that mediates the adaptive regulation of mitochondrial gene expression under low oxygen tension.
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40
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Upregulation of LYAR induces neuroblastoma cell proliferation and survival. Cell Death Differ 2017; 24:1645-1654. [PMID: 28686580 DOI: 10.1038/cdd.2017.98] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 04/24/2017] [Accepted: 05/12/2017] [Indexed: 12/19/2022] Open
Abstract
The N-Myc oncoprotein induces neuroblastoma by regulating gene transcription and consequently causing cell proliferation. Paradoxically, N-Myc is well known to induce apoptosis by upregulating pro-apoptosis genes, and it is not clear how N-Myc overexpressing neuroblastoma cells escape N-Myc-mediated apoptosis. The nuclear zinc finger protein LYAR has recently been shown to modulate gene expression by forming a protein complex with the protein arginine methyltransferase PRMT5. Here we showed that N-Myc upregulated LYAR gene expression by binding to its gene promoter. Genome-wide differential gene expression studies revealed that knocking down LYAR considerably upregulated the expression of oxidative stress genes including CHAC1, which depletes intracellular glutathione and induces oxidative stress. Although knocking down LYAR expression with siRNAs induced oxidative stress, neuroblastoma cell growth inhibition and apoptosis, co-treatment with the glutathione supplement N-acetyl-l-cysteine or co-transfection with CHAC1 siRNAs blocked the effect of LYAR siRNAs. Importantly, high levels of LYAR gene expression in human neuroblastoma tissues predicted poor event-free and overall survival in neuroblastoma patients, independent of the best current markers for poor prognosis. Taken together, our data suggest that LYAR induces proliferation and promotes survival of neuroblastoma cells by repressing the expression of oxidative stress genes such as CHAC1 and suppressing oxidative stress, and identify LYAR as a novel co-factor in N-Myc oncogenesis.
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41
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MYC Modulation around the CDK2/p27/SKP2 Axis. Genes (Basel) 2017; 8:genes8070174. [PMID: 28665315 PMCID: PMC5541307 DOI: 10.3390/genes8070174] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 06/23/2017] [Accepted: 06/24/2017] [Indexed: 12/20/2022] Open
Abstract
MYC is a pleiotropic transcription factor that controls a number of fundamental cellular processes required for the proliferation and survival of normal and malignant cells, including the cell cycle. MYC interacts with several central cell cycle regulators that control the balance between cell cycle progression and temporary or permanent cell cycle arrest (cellular senescence). Among these are the cyclin E/A/cyclin-dependent kinase 2 (CDK2) complexes, the CDK inhibitor p27KIP1 (p27) and the E3 ubiquitin ligase component S-phase kinase-associated protein 2 (SKP2), which control each other by forming a triangular network. MYC is engaged in bidirectional crosstalk with each of these players; while MYC regulates their expression and/or activity, these factors in turn modulate MYC through protein interactions and post-translational modifications including phosphorylation and ubiquitylation, impacting on MYC's transcriptional output on genes involved in cell cycle progression and senescence. Here we elaborate on these network interactions with MYC and their impact on transcription, cell cycle, replication and stress signaling, and on the role of other players interconnected to this network, such as CDK1, the retinoblastoma protein (pRB), protein phosphatase 2A (PP2A), the F-box proteins FBXW7 and FBXO28, the RAS oncoprotein and the ubiquitin/proteasome system. Finally, we describe how the MYC/CDK2/p27/SKP2 axis impacts on tumor development and discuss possible ways to interfere therapeutically with this system to improve cancer treatment.
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42
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Frank SB, Berger PL, Ljungman M, Miranti CK. Human prostate luminal cell differentiation requires NOTCH3 induction by p38-MAPK and MYC. J Cell Sci 2017; 130:1952-1964. [PMID: 28446540 DOI: 10.1242/jcs.197152] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 04/17/2017] [Indexed: 12/14/2022] Open
Abstract
Many pathways dysregulated in prostate cancer are also involved in epithelial differentiation. To better understand prostate tumor initiation, we sought to investigate specific genes and mechanisms required for normal basal to luminal cell differentiation. Utilizing human prostate basal epithelial cells and an in vitro differentiation model, we tested the hypothesis that regulation of NOTCH3 by the p38 MAPK family (hereafter p38-MAPK), via MYC, is required for luminal differentiation. Inhibition (SB202190 and BIRB796) or knockdown of p38α (also known as MAPK14) and/or p38δ (also known as MAPK13) prevented proper differentiation. Additionally, treatment with a γ-secretase inhibitor (RO4929097) or knockdown of NOTCH1 and/or NOTCH3 greatly impaired differentiation and caused luminal cell death. Constitutive p38-MAPK activation through MKK6(CA) increased NOTCH3 (but not NOTCH1) mRNA and protein levels, which was diminished upon MYC inhibition (10058-F4 and JQ1) or knockdown. Furthermore, we validated two NOTCH3 enhancer elements through a combination of enhancer (e)RNA detection (BruUV-seq) and luciferase reporter assays. Finally, we found that the NOTCH3 mRNA half-life increased during differentiation or upon acute p38-MAPK activation. These results reveal a new connection between p38-MAPK, MYC and NOTCH signaling, demonstrate two mechanisms of NOTCH3 regulation and provide evidence for NOTCH3 involvement in prostate luminal cell differentiation.
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Affiliation(s)
- Sander B Frank
- Laboratory of Integrin Signaling and Tumorigenesis, Van Andel Research Institute, Grand Rapids, MI 49503, USA.,Genetics Program, Michigan State University, East Lansing, MI 48824, USA.,Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, Tucson, AZ 85724, USA
| | - Penny L Berger
- Laboratory of Integrin Signaling and Tumorigenesis, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Mats Ljungman
- Translational Oncology Program, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Cindy K Miranti
- Laboratory of Integrin Signaling and Tumorigenesis, Van Andel Research Institute, Grand Rapids, MI 49503, USA .,Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, Tucson, AZ 85724, USA
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43
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Fan W, Yang H, Liu T, Wang J, Li TWH, Mavila N, Tang Y, Yang J, Peng H, Tu J, Annamalai A, Noureddin M, Krishnan A, Gores GJ, Martínez-Chantar ML, Mato JM, Lu SC. Prohibitin 1 suppresses liver cancer tumorigenesis in mice and human hepatocellular and cholangiocarcinoma cells. Hepatology 2017; 65:1249-1266. [PMID: 27981602 PMCID: PMC5360526 DOI: 10.1002/hep.28964] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 11/04/2016] [Accepted: 11/30/2016] [Indexed: 12/11/2022]
Abstract
UNLABELLED Prohibitin 1 (PHB1) is best known as a mitochondrial chaperone, and its role in cancer is conflicting. Mice lacking methionine adenosyltransferase α1 (MATα1) have lower PHB1 expression, and we reported that c-MYC interacts directly with both proteins. Furthermore, c-MYC and MATα1 exert opposing effects on liver cancer growth, prompting us to examine the interplay between PHB1, MATα1, and c-MYC and PHB1's role in liver tumorigenesis. We found that PHB1 is highly expressed in normal hepatocytes and bile duct epithelial cells and down-regulated in most human hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). In HCC and CCA cells, PHB1 expression correlates inversely with growth. PHB1 and MAT1A positively regulate each other's expression, whereas PHB1 negatively regulates the expression of c-MYC, MAFG, and c-MAF. Both PHB1 and MATα1 heterodimerize with MAX, bind to the E-box element, and repress E-box promoter activity. PHB1 promoter contains a repressive E-box element and is occupied mainly by MAX, MNT, and MATα1 in nonmalignant cholangiocytes and noncancerous tissues that switched to c-MYC, c-MAF, and MAFG in cancer cells and human HCC/CCA. All 8-month-old liver-specific Phb1 knockout mice developed HCC, and one developed CCA. Five-month-old Phb1 heterozygotes, but not Phb1 flox mice, developed aberrant bile duct proliferation; and one developed CCA 3.5 months after left and median bile duct ligation. Phb1 heterozygotes had a more profound fall in the expression of glutathione synthetic enzymes and higher hepatic oxidative stress following left and median bile duct ligation. CONCLUSION We have identified that PHB1, down-regulated in most human HCC and CCA, heterodimerizes with MAX to repress the E-box and positively regulates MAT1A while suppressing c-MYC, MAFG, and c-MAF expression; in mice, reduced PHB1 expression predisposes to the development of cholestasis-induced CCA. (Hepatology 2017;65:1249-1266).
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Affiliation(s)
- Wei Fan
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
- Department of Geriatrics, Guangzhou First People's Hospital, Guangzhou, China
- State Key Laboratory of Respiratory Diseases, First Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Heping Yang
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Ting Liu
- Department of Gastroenterology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jiaohong Wang
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Tony W H Li
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Nirmala Mavila
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Yuanyuan Tang
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
- Department of Oncology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - JinWon Yang
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Hui Peng
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Jian Tu
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
- Institute of Pharmacy & Pharmacology, University of South China, Hengyang, China
| | - Alagappan Annamalai
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Mazen Noureddin
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Anuradha Krishnan
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN
| | - Gregory J Gores
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN
| | - Maria L Martínez-Chantar
- CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (Ciberehd), Technology, Park of Bizkaia, Bizkaia, Spain
| | - José M Mato
- CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (Ciberehd), Technology, Park of Bizkaia, Bizkaia, Spain
| | - Shelly C Lu
- Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center, Los Angeles, CA
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Maltais L, Montagne M, Bédard M, Tremblay C, Soucek L, Lavigne P. Biophysical characterization of the b-HLH-LZ of ΔMax, an alternatively spliced isoform of Max found in tumor cells: Towards the validation of a tumor suppressor role for the Max homodimers. PLoS One 2017; 12:e0174413. [PMID: 28350847 PMCID: PMC5370111 DOI: 10.1371/journal.pone.0174413] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/08/2017] [Indexed: 11/19/2022] Open
Abstract
It is classically recognized that the physiological and oncogenic functions of Myc proteins depend on specific DNA binding enabled by the dimerization of its C-terminal basic-region-Helix-Loop-Helix-Leucine Zipper (b-HLH-LZ) domain with that of Max. However, a new paradigm is emerging, where the binding of the c-Myc/Max heterodimer to non-specific sequences in enhancers and promoters drives the transcription of genes involved in diverse oncogenic programs. Importantly, Max can form a stable homodimer even in the presence of c-Myc and bind DNA (specific and non-specific) with comparable affinity to the c-Myc/Max heterodimer. Intriguingly, alterations in the Max gene by germline and somatic mutations or changes in the gene product by alternative splicing (e.g. ΔMax) were recently associated with pheochromocytoma and glioblastoma, respectively. This has led to the proposition that Max is, by itself, a tumor suppressor. However, the actual mechanism through which it exerts such an activity remains to be elucidated. Here, we show that contrary to the WT motif, the b-HLH-LZ of ΔMax does not homodimerize in the absence of DNA. In addition, although ΔMax can still bind the E-box sequence as a homodimer, it cannot bind non-specific DNA in that form, while it can heterodimerize with c-Myc and bind E-box and non-specific DNA as a heterodimer with high affinity. Taken together, our results suggest that the WT Max homodimer is important for attenuating the binding of c-Myc to specific and non-specific DNA, whereas ΔMax is unable to do so. Conversely, the splicing of Max into ΔMax could provoke an increase in overall chromatin bound c-Myc. According to the new emerging paradigm, the splicing event and the stark reduction in homodimer stability and DNA binding should promote tumorigenesis impairing the tumor suppressor activity of the WT homodimer of Max.
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Affiliation(s)
- Loïka Maltais
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
- PROTÉO; Regroupement Stratégique sur la Fonction, la Structure et l'Ingénierie des Protéines, Université Laval, Québec, Canada
| | - Martin Montagne
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
- PROTÉO; Regroupement Stratégique sur la Fonction, la Structure et l'Ingénierie des Protéines, Université Laval, Québec, Canada
| | - Mikaël Bédard
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
- PROTÉO; Regroupement Stratégique sur la Fonction, la Structure et l'Ingénierie des Protéines, Université Laval, Québec, Canada
| | - Cynthia Tremblay
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
- PROTÉO; Regroupement Stratégique sur la Fonction, la Structure et l'Ingénierie des Protéines, Université Laval, Québec, Canada
| | - Laura Soucek
- Vall d’Hebron Institute of Oncology (VHIO), Hospital Vall d’Hebron, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Pierre Lavigne
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
- PROTÉO; Regroupement Stratégique sur la Fonction, la Structure et l'Ingénierie des Protéines, Université Laval, Québec, Canada
- * E-mail:
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Kumar D, Sharma N, Giri R. Therapeutic Interventions of Cancers Using Intrinsically Disordered Proteins as Drug Targets: c-Myc as Model System. Cancer Inform 2017; 16:1176935117699408. [PMID: 28469390 PMCID: PMC5392011 DOI: 10.1177/1176935117699408] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 02/20/2017] [Indexed: 12/29/2022] Open
Abstract
The concept of protein intrinsic disorder has taken the driving seat to understand regulatory proteins in general. Reports suggest that in mammals nearly 75% of signalling proteins contain long disordered regions with greater than 30 amino acid residues. Therefore, intrinsically disordered proteins (IDPs) have been implicated in several human diseases and should be considered as potential novel drug targets. Moreover, intrinsic disorder provides a huge multifunctional capability to hub proteins such as c-Myc and p53. c-Myc is the hot spot for understanding and developing therapeutics against cancers and cancer stem cells. Our past understanding is mainly based on in vitro and in vivo experiments conducted using c-Myc as whole protein. Using the reductionist approach, c-Myc oncoprotein has been divided into structured and disordered domains. A wealth of data is available dealing with the structured perspectives of c-Myc, but understanding c-Myc in terms of disordered domains has just begun. Disorderness provides enormous flexibility to proteins in general for binding to numerous partners. Here, we have reviewed the current progress on understanding c-Myc using the emerging concept of IDPs.
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Affiliation(s)
- Deepak Kumar
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
| | - Nitin Sharma
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
| | - Rajanish Giri
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, India
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Reduction of Ether-Type Glycerophospholipids, Plasmalogens, by NF-κB Signal Leading to Microglial Activation. J Neurosci 2017; 37:4074-4092. [PMID: 28292831 DOI: 10.1523/jneurosci.3941-15.2017] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 01/08/2023] Open
Abstract
Neuroinflammation characterized by activation of glial cells is observed in various neurodegenerative diseases including Alzheimer's disease (AD). Although the reduction of ether-type glycerophospholipids, plasmalogens (Pls), in the brain is reported in AD patients, the mechanism of the reduction and its impact on neuroinflammation remained elusive. In the present study, we found for the first time that various inflammatory stimuli reduced Pls levels in murine glial cells via NF-κB activation, which then downregulated a Pls-synthesizing enzyme, glycerone phosphate O-acyltransferase (Gnpat) through increased c-Myc recruitment onto the Gnpat promoter. We also found that systemic injection of lipopolysaccharide, aging, and chronic restraint stress reduced brain Pls contents that were associated with glial NF-κB activation, an increase in c-Myc expression, and downregulation of Gnpat in the mouse cortex and hippocampus. More interestingly, the reduction of Pls contents in the murine cortex itself could increase the activated phenotype of microglial cells and the expression of proinflammatory cytokines, suggesting further acceleration of neuroinflammation by reduction of brain Pls. A similar mechanism of Gnpat reduction was also found in human cell lines, triple-transgenic AD mouse brain, and postmortem human AD brain tissues. These findings suggest a novel mechanism of neuroinflammation that may explain prolonged progression of AD and help us to explore preventive and therapeutic strategies to treat neurodegenerative diseases.SIGNIFICANCE STATEMENT Ether-type glycerophospholipids, plasmalogens (Pls), are reduced in the brain of Alzheimer disease (AD) patients. We found that inflammatory stimuli reduced Pls contents by downregulation of the Pls-synthesizing enzyme glycerone phosphate O-acyltransferase (Gnpat) through NF-κB-mediated recruitment of c-Myc onto the Gnpat promoter in both murine and human cell lines. Murine brains after systemic lipopolysaccharide, chronic stress, and aging, as well as triple-transgenic AD mice and postmortem human AD brain tissues all showed increased c-Myc and reduced Gnpat expression. Interestingly, knockdown of Gnpat itself activated NF-κB in glial cell lines and microglia in mouse cortex. Our findings provide a new insight into the mechanism of neuroinflammation and may help to develop a novel therapeutic approach for neurodegenerative diseases such as AD.
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Lorentzen A, Mitchelmore C. NDRG2 gene copy number is not altered in colorectal carcinoma. World J Clin Oncol 2017; 8:67-74. [PMID: 28246586 PMCID: PMC5309715 DOI: 10.5306/wjco.v8.i1.67] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 09/12/2016] [Accepted: 12/28/2016] [Indexed: 02/06/2023] Open
Abstract
AIM To investigate if the down-regulation of N-myc Downstream Regulated Gene 2 (NDRG2) expression in colorectal carcinoma (CRC) is due to loss of the NDRG2 allele(s).
METHODS The following were investigated in the human colorectal cancer cell lines DLD-1, LoVo and SW-480: NDRG2 mRNA expression levels using quantitative reverse transcription-polymerase chain reaction (qRT-PCR); interaction of the MYC gene-regulatory protein with the NDRG2 promoter using chromatin immunoprecipitation; and NDRG2 promoter methylation using bisulfite sequencing. Furthermore, we performed qPCR to analyse the copy numbers of NDRG2 and MYC genes in the above three cell lines, 8 normal colorectal tissue samples and 40 CRC tissue samples.
RESULTS As expected, NDRG2 mRNA levels were low in the three colorectal cancer cell lines, compared to normal colon. Endogenous MYC protein interacted with the NDRG2 core promoter in all three cell lines. In addition, the NDRG2 promoter was heavily methylated in these cell lines, suggesting an epigenetic regulatory mechanism. Unaltered gene copy numbers of NDRG2 were observed in the three cell lines. In the colorectal tissues, one normal and three CRC samples showed partial or complete loss of one NDRG2 allele. In contrast, the MYC gene was amplified in one cell line and in more than 40% of the CRC cases.
CONCLUSION Our study suggests that the reduction in NDRG2 expression observed in CRC is due to transcriptional repression by MYC and promoter methylation, and is not due to allelic loss.
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Kobayashi T. Expression and Regulation of Tal2 during Neuronal Differentiation in P19 Cells. YAKUGAKU ZASSHI 2017; 137:61-71. [PMID: 28049897 DOI: 10.1248/yakushi.16-00176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
T-cell acute lymphocytic leukemia 2 (Tal2) is a gene encoding a member of the basic helix-loop-helix transcription factor family, which is essential for the normal development of the mouse brain. We found that Tal2 was induced during neural differentiation in P19 cells, which are pluripotent mouse embryonal carcinoma cells that differentiate into the neural lineage upon both exposure to all-trans retinoic acid (atRA) and the formation of cell aggregation. Tal2 expression during neural differentiation in P19 cells was detected within 3 h after induction with atRA and retinoic acid receptor α (RARα). The atRA-RARα complex is known to bind to a characteristic retinoic acid response element (RARE) located in the promoter of target genes. We found a RARE-like element in the intron of Tal2. We also found a TATA-box-like element in the 5' region. The TATA-box-like element functioned as a core promoter, and TATA- box binding protein bound to this element upstream of Tal2 in P19 cells. The RARE-like element responded to atRA signaling that activated the transcription, and RARα was bound to this element in the intron of Tal2 in P19 cells. Furthermore, the interaction between these elements on Tal2 was confirmed in a chromatin immunoprecipitation assay. Because the neural differentiation of P19 cells mimics in part the development of the nervous system, P19 cells are useful for studying the mechanism underlying the role of Tal2 in neural differentiation. Further work is underway to clarify the function of Tal2 in neural differentiation using the differentiation system of P19 cells.
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Resende LS, Amaral CE, Soares RBS, Alves AS, Alves-dos-Santos L, Britto LRG, Chiavegatto S. Social stress in adolescents induces depression and brain-region-specific modulation of the transcription factor MAX. Transl Psychiatry 2016; 6:e914. [PMID: 27727240 PMCID: PMC5315556 DOI: 10.1038/tp.2016.202] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 08/18/2016] [Accepted: 08/24/2016] [Indexed: 11/17/2022] Open
Abstract
MAX is a conserved constitutive small phosphoprotein from a network of transcription factors that are extensively studied in tumorigenesis and whose functions affect cell proliferation, differentiation and death. Inspired by its higher expression during development and in regions involved in emotional behaviors, we hypothesized its involvement in cerebral changes caused by early-life stress. We studied the effects of repeated social stress during adolescence on behaviors and on MAX and its putative partner MYC. Thirty-day-old C57BL/6 male mice underwent brief daily social defeat stress from an adult aggressor for 21 days. Following social stress episodes and housing in social groups after each defeat, adolescent mice exhibit depressive-like, but not anxiety-like behaviors and show higher MAX nuclear immunoreactivity in hippocampal (HC) but not prefrontal cortical (PFC) neurons. Conversely, MAX immunoreactivity is lower in the striatum (ST) of defeated adolescents. The positive correlation between MAX and MYC levels in the PFC revealed disruptions in both the HC and ST. The changes in MAX protein levels are not due to differential gene expression or protein degradation in those regions, suggesting that posttranscriptional modifications occurred. These findings indicate that repeated, brief social defeat in adolescent male mice, combined with group housing, is a useful protocol to study a subtype of depression that is dissociated from generalized (non-social) anxiety. To our knowledge, this is the first report of an association between dysregulation of the MAX-MYC network in the brain and a behavior, suggesting a novel approach for exploiting the neuroplasticity associated with depression.
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Affiliation(s)
- L S Resende
- Department of Pharmacology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil,National Institute for Developmental Psychiatry (INCT-CNPq), Department of Psychiatry, Institute of Psychiatry, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - C E Amaral
- Department of Pharmacology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil,National Institute for Developmental Psychiatry (INCT-CNPq), Department of Psychiatry, Institute of Psychiatry, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - R B S Soares
- National Institute for Developmental Psychiatry (INCT-CNPq), Department of Psychiatry, Institute of Psychiatry, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - A S Alves
- Department of Physiology and Biophysics, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil
| | - L Alves-dos-Santos
- Department of Pharmacology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil,National Institute for Developmental Psychiatry (INCT-CNPq), Department of Psychiatry, Institute of Psychiatry, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - L R G Britto
- Department of Physiology and Biophysics, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil
| | - S Chiavegatto
- Department of Pharmacology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil,National Institute for Developmental Psychiatry (INCT-CNPq), Department of Psychiatry, Institute of Psychiatry, University of Sao Paulo Medical School, Sao Paulo, Brazil,Department of Pharmacology, Laboratory of Behavioral and Molecular Neurosciences, Biomedical Sciences Institute, University of Sao Paulo, 1524, Prof. Lineu Prestes Avenue, 3rd floor, 325, Sao Paulo 05508-000, SP, Brazil. E-mail
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50
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Gao R, Wang L, Cai H, Zhu J, Yu L. E3 Ubiquitin Ligase RLIM Negatively Regulates c-Myc Transcriptional Activity and Restrains Cell Proliferation. PLoS One 2016; 11:e0164086. [PMID: 27684546 PMCID: PMC5042457 DOI: 10.1371/journal.pone.0164086] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 09/19/2016] [Indexed: 11/19/2022] Open
Abstract
RNF12/RLIM is a RING domain-containing E3 ubiquitin ligase whose function has only begun to be elucidated recently. Although RLIM was reported to play important roles in some biological processes such as imprinted X-chromosome inactivation and regulation of TGF-β pathway etc., other functions of RLIM are largely unknown. Here, we identified RLIM as a novel E3 ubiquitin ligase for c-Myc, one of the most frequently deregulated oncoproteins in human cancers. RLIM associates with c-Myc in vivo and in vitro independently of the E3 ligase activity of RLIM. Moreover, RLIM promotes the polyubiquitination of c-Myc protein independently of Ser62 and Thr58 phosphorylation of c-Myc. However, RLIM-mediated ubiquitination does not affect c-Myc stability. Instead, RLIM inhibits the transcriptional activity of c-Myc through which RLIM restrains cell proliferation. Our results suggest that RLIM may function as a tumor suppressor by controlling the activity of c-Myc oncoprotein.
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Affiliation(s)
- Rui Gao
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, P.R. China
- * E-mail:
| | - Lan Wang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, P.R. China
- Shanghai Center for Systems Biomedicine, Key Laboratory of Systems Biomedicine Ministry of Education, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Hao Cai
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, P.R. China
| | - Jingjing Zhu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, P.R. China
| | - Long Yu
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, P.R. China
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