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Giaimo BD, Friedrich T, Ferrante F, Bartkuhn M, Borggrefe T. Comprehensive genomic features indicative for Notch responsiveness. Nucleic Acids Res 2024:gkae292. [PMID: 38647081 DOI: 10.1093/nar/gkae292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/21/2024] [Accepted: 04/05/2024] [Indexed: 04/25/2024] Open
Abstract
Transcription factor RBPJ is the central component in Notch signal transduction and directly forms a coactivator complex together with the Notch intracellular domain (NICD). While RBPJ protein levels remain constant in most tissues, dynamic expression of Notch target genes varies depending on the given cell-type and the Notch activity state. To elucidate dynamic RBPJ binding genome-wide, we investigated RBPJ occupancy by ChIP-Seq. Surprisingly, only a small set of the total RBPJ sites show a dynamic binding behavior in response to Notch signaling. Compared to static RBPJ sites, dynamic sites differ in regard to their chromatin state, binding strength and enhancer positioning. Dynamic RBPJ sites are predominantly located distal to transcriptional start sites (TSSs), while most static sites are found in promoter-proximal regions. Importantly, gene responsiveness is preferentially associated with dynamic RBPJ binding sites and this static and dynamic binding behavior is repeatedly observed across different cell types and species. Based on the above findings we used a machine-learning algorithm to predict Notch responsiveness with high confidence in different cellular contexts. Our results strongly support the notion that the combination of binding strength and enhancer positioning are indicative of Notch responsiveness.
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Affiliation(s)
- Benedetto Daniele Giaimo
- Institute of Biochemistry, Justus-Liebig-University Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
| | - Tobias Friedrich
- Institute of Biochemistry, Justus-Liebig-University Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
- Biomedical Informatics and Systems Medicine, Justus-Liebig-University Giessen, Aulweg 128, 35392 Giessen, Germany
| | - Francesca Ferrante
- Institute of Biochemistry, Justus-Liebig-University Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
| | - Marek Bartkuhn
- Biomedical Informatics and Systems Medicine, Justus-Liebig-University Giessen, Aulweg 128, 35392 Giessen, Germany
- Institute for Lung Health, Aulweg 132, 35392 Giessen, Germany
| | - Tilman Borggrefe
- Institute of Biochemistry, Justus-Liebig-University Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
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Braune EB, Geist F, Tang X, Kalari K, Boughey J, Wang L, Leon-Ferre RA, D'Assoro AB, Ingle JN, Goetz MP, Kreis J, Wang K, Foukakis T, Seshire A, Wienke D, Lendahl U. Identification of a Notch transcriptomic signature for breast cancer. Breast Cancer Res 2024; 26:4. [PMID: 38172915 PMCID: PMC10765899 DOI: 10.1186/s13058-023-01757-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Dysregulated Notch signalling contributes to breast cancer development and progression, but validated tools to measure the level of Notch signalling in breast cancer subtypes and in response to systemic therapy are largely lacking. A transcriptomic signature of Notch signalling would be warranted, for example to monitor the effects of future Notch-targeting therapies and to learn whether altered Notch signalling is an off-target effect of current breast cancer therapies. In this report, we have established such a classifier. METHODS To generate the signature, we first identified Notch-regulated genes from six basal-like breast cancer cell lines subjected to elevated or reduced Notch signalling by culturing on immobilized Notch ligand Jagged1 or blockade of Notch by γ-secretase inhibitors, respectively. From this cadre of Notch-regulated genes, we developed candidate transcriptomic signatures that were trained on a breast cancer patient dataset (the TCGA-BRCA cohort) and a broader breast cancer cell line cohort and sought to validate in independent datasets. RESULTS An optimal 20-gene transcriptomic signature was selected. We validated the signature on two independent patient datasets (METABRIC and Oslo2), and it showed an improved coherence score and tumour specificity compared with previously published signatures. Furthermore, the signature score was particularly high for basal-like breast cancer, indicating an enhanced level of Notch signalling in this subtype. The signature score was increased after neoadjuvant treatment in the PROMIX and BEAUTY patient cohorts, and a lower signature score generally correlated with better clinical outcome. CONCLUSIONS The 20-gene transcriptional signature will be a valuable tool to evaluate the response of future Notch-targeting therapies for breast cancer, to learn about potential effects on Notch signalling from conventional breast cancer therapies and to better stratify patients for therapy considerations.
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Affiliation(s)
- Eike-Benjamin Braune
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | | | - Xiaojia Tang
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Krishna Kalari
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Judy Boughey
- Department of Surgery, Mayo Clinic, Rochester, MN, USA
| | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
| | | | | | - James N Ingle
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | - Matthew P Goetz
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, USA
| | | | - Kang Wang
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Theodoros Foukakis
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Urban Lendahl
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
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Cao R, Jones DTD, Pan L, Wang S, Rawson S, Aster JC, Blacklow SC. Molecular Mechanism of PP2A/B55α Inhibition by IER5. bioRxiv 2023:2023.08.29.555174. [PMID: 37693604 PMCID: PMC10491241 DOI: 10.1101/2023.08.29.555174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
PP2A serine/threonine protein phosphatases are heterotrimeric complexes that have a wide range of essential physiologic functions. The B55α form of PP2A has critical roles in cell cycle regulation, mitotic exit, and the DNA damage response1-6. Its activity is modulated by additional regulatory proteins, such as ARPP197, FAM122A8, and IER59. However, the precise mechanisms underlying the modulation of PP2A activity by these proteins remain elusive. Here, we show that IER5 inhibits pTau dephosphorylation by PP2A/B55α in biochemical assays and report a cryoelectron microscopy structure of the PP2A/B55α-IER5 complex, which reveals that IER5 occludes a surface on B55α used for substrate recruitment10-12. Mutation of interface residues on IER5 interferes with recovery of B55α in co-immunoprecipitation assays and suppresses events in squamous carcinoma cells, such as KRT1 expression, that depend on inhibition of PP2A/B55α by IER59. These studies define the molecular basis for PP2A inhibition by IER5 and suggest a roadmap for selective pharmacologic modulation of PP2A/B55α complexes.
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Affiliation(s)
- Ruili Cao
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA USA
| | - Daniel TD Jones
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA USA
| | - Li Pan
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA USA
| | - Shumei Wang
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA USA
| | - Shaun Rawson
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA USA
| | - Jon C Aster
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA USA
| | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA USA
- Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA USA
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Su B, Lim D, Qi C, Zhang Z, Wang J, Zhang F, Dong C, Feng Z. VPA mediates bidirectional regulation of cell cycle progression through the PPP2R2A-Chk1 signaling axis in response to HU. Cell Death Dis 2023; 14:114. [PMID: 36781846 PMCID: PMC9925808 DOI: 10.1038/s41419-023-05649-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/15/2023]
Abstract
Cell cycle checkpoint kinases play a pivotal role in protecting against replicative stress. In this study, valproic acid (VPA), a histone deacetylase inhibitor (HDACi), was found to promote breast cancer MCF-7 cells to traverse into G2/M phase for catastrophic injury by promoting PPP2R2A (the B-regulatory subunit of Phosphatase PP2A) to facilitate the dephosphorylation of Chk1 at Ser317 and Ser345. By contrast, VPA protected normal 16HBE cells from HU toxicity through decreasing PPP2R2A expression and increasing Chk1 phosphorylation. The effect of VPA on PPP2R2A was at the post-transcription level through HDAC1/2. The in vitro results were affirmed in vivo. Patients with lower PPP2R2A expression and higher pChk1 expression showed significantly worse survival. PPP2R2A D197 and N181 are essential for PPP2R2A-Chk1 signaling and VPA-mediated bidirectional effect on augmenting HU-induced tumor cell death and protecting normal cells.
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Affiliation(s)
- Benyu Su
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - David Lim
- Translational Health Research Institute, School of Health Sciences, Western Sydney University, Campbelltown, NSW, Australia
- College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
| | - Chenyang Qi
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Zhongwei Zhang
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Junxiao Wang
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Fengmei Zhang
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Chao Dong
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.
| | - Zhihui Feng
- Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.
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Doi K, Takeuchi H, Sakurai H. PP2A-B55 and its adapter proteins IER2 and IER5 regulate the activity of RB family proteins and the expression of cell cycle-related genes. FEBS J 2023; 290:745-762. [PMID: 36047562 DOI: 10.1111/febs.16612] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 08/05/2022] [Accepted: 08/30/2022] [Indexed: 02/04/2023]
Abstract
The retinoblastoma (RB) tumour suppressor protein regulates cell proliferation, motility, differentiation and apoptosis. The phosphorylation state of RB is modulated by kinases and phosphatases, and RB exhibits phosphorylation-sensitive interactions with E2F family transcription factors. Here, we characterize RB dephosphorylation by protein phosphatase 2A (PP2A). The growth factor-inducible immediate early response (IER) proteins IER2 and IER5 possess an adapter-like function in which IER proteins bind to both PP2A and its target proteins and enhance PP2A activity towards the proteins. IER2 interacts with RB and facilitates dephosphorylation of RB at T821/T826 by PP2A. In IER2 knockdown cells, elevated phosphorylation of RB resulted in reduced binding of RB to the promoters and derepression of cyclin D1 and p21. IER5 binds to both RB and RB-like 1 (p107/RBL1), enhances dephosphorylation of these proteins by PP2A and represses the expression of various cell cycle-related genes. However, IER2-regulated dephosphorylation at T821/T826 is not necessary for the repression function of RB in cell mobility-related gene expression. Our data identify PP2A adapter proteins as critical regulators of RB family proteins and suggest that the phosphorylation status of RB differentially affects gene expression.
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Affiliation(s)
- Kuriko Doi
- Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, Japan
| | - Hiroto Takeuchi
- Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, Japan
| | - Hiroshi Sakurai
- Division of Health Sciences, Graduate School of Medical Science, Kanazawa University, Japan
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Ferrante F, Giaimo BD, Friedrich T, Sugino T, Mertens D, Kugler S, Gahr BM, Just S, Pan L, Bartkuhn M, Potente M, Oswald F, Borggrefe T. Hydroxylation of the NOTCH1 intracellular domain regulates Notch signaling dynamics. Cell Death Dis 2022; 13:600. [PMID: 35821235 PMCID: PMC9276811 DOI: 10.1038/s41419-022-05052-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/22/2022] [Accepted: 06/28/2022] [Indexed: 01/21/2023]
Abstract
Notch signaling plays a pivotal role in the development and, when dysregulated, it contributes to tumorigenesis. The amplitude and duration of the Notch response depend on the posttranslational modifications (PTMs) of the activated NOTCH receptor - the NOTCH intracellular domain (NICD). In normoxic conditions, the hydroxylase FIH (factor inhibiting HIF) catalyzes the hydroxylation of two asparagine residues of the NICD. Here, we investigate how Notch-dependent gene transcription is regulated by hypoxia in progenitor T cells. We show that the majority of Notch target genes are downregulated upon hypoxia. Using a hydroxyl-specific NOTCH1 antibody we demonstrate that FIH-mediated NICD1 hydroxylation is reduced upon hypoxia or treatment with the hydroxylase inhibitor dimethyloxalylglycine (DMOG). We find that a hydroxylation-resistant NICD1 mutant is functionally impaired and more ubiquitinated. Interestingly, we also observe that the NICD1-deubiquitinating enzyme USP10 is downregulated upon hypoxia. Moreover, the interaction between the hydroxylation-defective NICD1 mutant and USP10 is significantly reduced compared to the NICD1 wild-type counterpart. Together, our data suggest that FIH hydroxylates NICD1 in normoxic conditions, leading to the recruitment of USP10 and subsequent NICD1 deubiquitination and stabilization. In hypoxia, this regulatory loop is disrupted, causing a dampened Notch response.
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Affiliation(s)
- Francesca Ferrante
- grid.8664.c0000 0001 2165 8627Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
| | - Benedetto Daniele Giaimo
- grid.8664.c0000 0001 2165 8627Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
| | - Tobias Friedrich
- grid.8664.c0000 0001 2165 8627Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392 Giessen, Germany ,Biomedical Informatics and Systems Medicine, Science Unit for Basic and Clinical Medicine, Aulweg 128, 35392 Giessen, Germany
| | - Toshiya Sugino
- grid.418032.c0000 0004 0491 220XMax Planck Institute for Heart and Lung Research, Angiogenesis and Metabolism Laboratory, Ludwigstr. 43, 61231 Bad Nauheim, Germany
| | - Daniel Mertens
- grid.410712.10000 0004 0473 882XUniversity Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine III, Albert-Einstein-Allee 23, 89081 Ulm, Germany ,grid.7497.d0000 0004 0492 0584German Cancer Research Center (DKFZ), Bridging Group Mechanisms of Leukemogenesis, B061, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Sabrina Kugler
- grid.410712.10000 0004 0473 882XUniversity Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine III, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Bernd Martin Gahr
- grid.410712.10000 0004 0473 882XUniversity Medical Center Ulm, Center for Internal Medicine, Molecular Cardiology, Department of Internal Medicine II, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Steffen Just
- grid.410712.10000 0004 0473 882XUniversity Medical Center Ulm, Center for Internal Medicine, Molecular Cardiology, Department of Internal Medicine II, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Leiling Pan
- grid.410712.10000 0004 0473 882XUniversity Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine I, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Marek Bartkuhn
- Biomedical Informatics and Systems Medicine, Science Unit for Basic and Clinical Medicine, Aulweg 128, 35392 Giessen, Germany ,Institute for Lung Health (ILH), Aulweg 132, 35392 Giessen, Germany
| | - Michael Potente
- grid.418032.c0000 0004 0491 220XMax Planck Institute for Heart and Lung Research, Angiogenesis and Metabolism Laboratory, Ludwigstr. 43, 61231 Bad Nauheim, Germany ,grid.484013.a0000 0004 6879 971XBerlin Institute of Health (BIH) at Charité-Universitätsmedizin Berlin, Berlin, Germany ,grid.419491.00000 0001 1014 0849Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13125 Berlin, Germany
| | - Franz Oswald
- grid.410712.10000 0004 0473 882XUniversity Medical Center Ulm, Center for Internal Medicine, Department of Internal Medicine I, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Tilman Borggrefe
- grid.8664.c0000 0001 2165 8627Institute of Biochemistry, University of Giessen, Friedrichstrasse 24, 35392 Giessen, Germany
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Abstract
ABSTRACT
Cellular stress is known to function in synergistic cooperation with oncogenic mutations during tumorigenesis to drive cancer progression. Oncogenic RAS is a strong inducer of a variety of pro-tumorigenic cellular stresses, and also enhances the ability of cells to tolerate these stresses through multiple mechanisms. Many of these oncogenic, RAS-driven, stress-adaptive mechanisms have also been implicated in tolerance and resistance to chemotherapy and to therapies that target the RAS pathway. Understanding how oncogenic RAS shapes cellular stress adaptation and how this functions in drug resistance is of vital importance for identifying new therapeutic targets and therapeutic combinations to treat RAS-driven cancers.
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Affiliation(s)
- Alexandra Redding
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Andrew E. Aplin
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Elda Grabocka
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Abstract
Nearly two million cases of cutaneous squamous cell carcinoma (cSCC) are diagnosed every year in the United States alone. cSCC is notable for both its prevalence and its propensity for invasion and metastasis. For many patients, surgery is curative. However, patients experiencing immunosuppression or recurrent, advanced, and metastatic disease still face limited therapeutic options and significant mortality. cSCC forms after decades of sun exposure and possesses the highest known mutation rate of all cancers. This mutational burden complicates efforts to identify the primary factors driving cSCC initiation and progression, which in turn hinders the development of targeted therapeutics. In this review, we summarize the mutations and alterations that have been observed in patients’ cSCC tumors, affecting signaling pathways, transcriptional regulators, and the microenvironment. We also highlight novel therapeutic opportunities in development and clinical trials.
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Affiliation(s)
- Stephenie Droll
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
| | - Xiaomin Bao
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA, .,Department of Dermatology, Northwestern University, Chicago, IL, USA.,Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL, USA
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Ding L, Zhao X, Xiong Q, Jiang X, Liu X, Ding K, Zhou P. Cdc25B is transcriptionally inhibited by IER5 through the NF-YB transcription factor in irradiation-treated HeLa cells. Toxicol Res (Camb) 2021; 10:875-884. [PMID: 34484679 DOI: 10.1093/toxres/tfab069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/28/2021] [Accepted: 07/05/2021] [Indexed: 12/09/2022] Open
Abstract
Cervical cancer (CC) is a type of pelvic malignant tumor that severely threatens women's health. Current evidence suggests that IER5, as a potential radiosensitizer, promotes irradiation-induced apoptosis in CC tissues in patients undergoing chemoradiotherapy. IER5 has been shown to be involved in the G2/M-phase transition. In the present study, we used Cdc25B as the breakthrough point to explore the underlying mechanism of IER5 in the cell cycle regulation of radiation-damaged HeLa cells. IER5 was evidently upregulated after irradiation, but Cdc25B was significantly downregulated. In monoclonal IER5-silenced HeLa cells, irradiation-induced downregulation of Cdc25B was attenuated. The effect of irradiation on Cdc25B promoter activity was determined by dual-luciferase reporter assays. The response elements on the Cdc25B promoter related to irradiation were predicted by JASPAR. These conserved sequences were mutated individually or in combination by splicing-by-overlap extension PCR, and their function was confirmed by dual-luciferase reporter assays. The enrichment efficiency of transcription factors after irradiation was determined by chromatin immunoprecipitation (ChIP) assay. Both Sp1/Sp3 and NF-YB binding sites were involved in irradiation-mediated regulation of Cdc25B. IER5 was involved in irradiation-mediated regulation of Cdc25B through the NF-YB binding site. Furthermore, ChIP assays showed that IER5 bound to the Cdc25B promoter, and the binding of IER5 to the Cdc25B promoter region in irradiation-induced HeLa cells induced the release of the coactivator p300 through interaction with NF-YB. Taken together, these findings indicate that IER5 is the transcriptional repressor that accelerates the downregulation of Cdc25B expression after irradiation.
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Affiliation(s)
- Lixin Ding
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Xianzhe Zhao
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Qiang Xiong
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Xiaoyan Jiang
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Xiaodan Liu
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Haidian District, Beijing 100850, P. R. China
| | - Kuke Ding
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Pingkun Zhou
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Haidian District, Beijing 100850, P. R. China
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Wang L, Li S, Qi L, Ling L. Long Noncoding RNA HCG9 Promotes Osteosarcoma Progression through RAD51 by Acting as a ceRNA of miR-34b-3p. Mediators Inflamm 2021; 2021:9978882. [PMID: 34456631 DOI: 10.1155/2021/9978882] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/20/2021] [Indexed: 01/01/2023] Open
Abstract
Background Long noncoding RNAs (lncRNAs) have critical regulatory functions in biological and pathological activities during osteosarcoma progression. It is important to elucidate the expression pattern and reveal the underlying mechanisms of the newly identified lncRNAs. Methods Herein, we screened the differentially expressed lncRNAs in osteosarcoma tumors and cell lines using lncRNA microarray. The candidate lncRNA was further verified by qRT-PCR, and the association of gene expression with clinicopathological features was evaluated by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The targeting miRNA was identified using starBase analysis, and the competing endogenous RNA (ceRNA) network was established by STRING. Overexpression and silence of RNA were detected by qRT-PCR. Osteosarcoma cell proliferation was measured with CCK-8 assay, and the migration and invasion were evaluated with Transwell assay. Colony formation assay was observed. Flow cytometry evaluated the cell cycle. Western blot was performed to detect the mitotic markers and apoptosis-related proteins. A nude mouse tumor formation experiment was used to evaluate osteosarcoma progression in vivo. Cooverexpressing miR-34b-3p with RAD51 reversed the miR-34b-3p-induced changes in proliferation, the cell cycle, the expression of H2A.X, and that of apoptosis-related proteins. Results HCG9 was identified as osteosarcoma-associated lncRNA. Osteosarcoma tissues and cell lines expressed higher levels of HCG9 as compared to normal tissues and osteoblasts, and high expression of HCG9 was further proved to be related to metastasis and the grade of osteosarcoma in clinical cases. Knockdown of HCG9 inhibited the proliferation, migration, and invasion of osteosarcoma cells. miR-34b-3p was identified as the target of HCG9, and RAD51 acted as a potential target of miR-34b-3p. Cooverexpressing miR-34b-3p with HCG9 partially suppressed the HCG9-stimulated proliferation, migration, and invasion of osteosarcoma cells in vitro and delayed the tumor progression in vivo. Conclusion We discovered that lncRNA HCG9 promoted the proliferation of osteosarcoma cells via suppressing miR-34b-3p. Our study provides novel biomarkers and potential therapeutic targets for osteosarcoma treatment.
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Momeny M, Arsiola T, Westermarck J. Cancer stem cell phosphatases. Biochem J 2021; 478:2899-920. [PMID: 34319405 DOI: 10.1042/BCJ20210254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 12/15/2022]
Abstract
Cancer stem cells (CSCs) are involved in the initiation and progression of human malignancies by enabling cancer tissue self-renewal capacity and constituting the therapy-resistant population of tumor cells. However, despite the exhausting characterization of CSC genetics, epigenetics, and kinase signaling, eradication of CSCs remains an unattainable goal in most human malignancies. While phosphatases contribute equally with kinases to cellular phosphoregulation, our understanding of phosphatases in CSCs lags severely behind our knowledge about other CSC signaling mechanisms. Many cancer-relevant phosphatases have recently become druggable, indicating that further understanding of the CSC phosphatases might provide novel therapeutic opportunities. This review summarizes the current knowledge about fundamental, but yet poorly understood involvement of phosphatases in the regulation of major CSC signaling pathways. We also review the functional roles of phosphatases in CSC self-renewal, cancer progression, and therapy resistance; focusing particularly on hematological cancers and glioblastoma. We further discuss the small molecule targeting of CSC phosphatases and their therapeutic potential in cancer combination therapies.
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12
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Ferreira A, Aster JC. Notch signaling in cancer: Complexity and challenges on the path to clinical translation. Semin Cancer Biol 2021; 85:95-106. [PMID: 33862222 DOI: 10.1016/j.semcancer.2021.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/29/2021] [Accepted: 04/11/2021] [Indexed: 12/22/2022]
Abstract
Notch receptors participate in a conserved pathway in which ligands expressed on neighboring cells trigger a series of proteolytic cleavages that allow the intracellular portion of the receptor to travel to the nucleus and form a short-lived transcription complex that turns on target gene expression. The directness and seeming simplicity of this signaling mechanism belies the complexity of the outcomes of Notch signaling in normal cells, which are highly context and dosage dependent. This complexity is reflected in the diverse roles of Notch in cancers of various types, in which Notch may be oncogenic or tumor suppressive and may have a wide spectrum of effects on tumor cells and stromal elements. This review provides an overview of the roles of Notch in cancer and discusses challenges to clinical translation of Notch targeting agents as well as approaches that may overcome these hurdles.
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Affiliation(s)
- Antonio Ferreira
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA, 02115, United States
| | - Jon C Aster
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA, 02115, United States.
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Misiorek JO, Przybyszewska-Podstawka A, Kałafut J, Paziewska B, Rolle K, Rivero-Müller A, Nees M. Context Matters: NOTCH Signatures and Pathway in Cancer Progression and Metastasis. Cells 2021; 10:E94. [PMID: 33430387 DOI: 10.3390/cells10010094] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/23/2020] [Accepted: 12/30/2020] [Indexed: 02/06/2023] Open
Abstract
The Notch signaling pathway is a critical player in embryogenesis but also plays various roles in tumorigenesis, with both tumor suppressor and oncogenic activities. Mutations, deletions, amplifications, or over-expression of Notch receptors, ligands, and a growing list of downstream Notch-activated genes have by now been described for most human cancer types. Yet, it often remains unclear what may be the functional impact of these changes for tumor biology, initiation, and progression, for cancer therapy, and for personalized medicine. Emerging data indicate that Notch signaling can also contribute to increased aggressive properties such as invasion, tumor heterogeneity, angiogenesis, or tumor cell dormancy within solid cancer tissues; especially in epithelial cancers, which are in the center of this review. Notch further supports the “stemness” of cancer cells and helps define the stem cell niche for their long-term survival, by integrating the interaction between cancer cells and the cells of the tumor microenvironment (TME). The complexity of Notch crosstalk with other signaling pathways and its roles in cell fate and trans-differentiation processes such as epithelial-to-mesenchymal transition (EMT) point to this pathway as a decisive player that may tip the balance between tumor suppression and promotion, differentiation and invasion. Here we not only review the literature, but also explore genomic databases with a specific focus on Notch signatures, and how they relate to different stages in tumor development. Altered Notch signaling hereby plays a key role for tumor cell survival and coping with a broad spectrum of vital issues, contributing to failed therapies, poor patient outcome, and loss of lives.
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