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Truong T, Martin K, Salemi M, Ray A, Phinney BS, Penn BH. The balance between antiviral and antibacterial responses during M. tuberculosis infection is regulated by the ubiquitin ligase CBL. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.15.594178. [PMID: 38798543 PMCID: PMC11118416 DOI: 10.1101/2024.05.15.594178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
As a first line of host defense, macrophages must be able to effectively sense and respond to diverse types of pathogens, and while a particular type of immune response may be beneficial in some circumstances, it can be detrimental in others. Upon infecting a macrophage, M. tuberculosis (Mtb) induces proinflammatory cytokines that activate antibacterial responses. Surprisingly, Mtb also triggers antiviral responses that actually hinder the ability of macrophages to control Mtb infection. The ubiquitin ligase CBL suppresses these antiviral responses and shifts macrophages toward a more antibacterial state during Mtb infection, however, the mechanisms by which CBL regulates immune signaling are unknown. We found that CBL controls responses to multiple stimuli and broadly suppresses the expression of antiviral effector genes. We then used mass-spectrometry to investigate potential CBL substrates and identified over 46,000 ubiquitylated peptides in Mtb-infected macrophages, as well as roughly 400 peptides with CBL-dependent ubiquitylation. We then performed genetic interaction analysis of CBL and its putative substrates, and identified the Fas associated factor 2 (FAF2) adapter protein as a key signaling molecule protein downstream of CBL. Together, these analyses identify thousands of new ubiquitin-mediated signaling events during the innate immune response and reveal an important new regulatory hub in this response.
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Affiliation(s)
- Tina Truong
- Department of Internal Medicine, University of California, Davis, Davis, California, United States of America
- Graduate Group in Immunology, University of California, Davis, Davis, California, United States of America
| | - Kelsey Martin
- Department of Internal Medicine, University of California, Davis, Davis, California, United States of America
| | - Michelle Salemi
- Proteomics Core Facility, University of California, Davis, Davis, California, United States of America
| | - Abigail Ray
- Department of Internal Medicine, University of California, Davis, Davis, California, United States of America
- Microbiology Graduate Group, University of California, Davis, Davis, California, United States of America
| | - Brett S Phinney
- Proteomics Core Facility, University of California, Davis, Davis, California, United States of America
| | - Bennett H Penn
- Department of Internal Medicine, University of California, Davis, Davis, California, United States of America
- Department of Medical Microbiology and Immunology, University of California, Davis, Davis, California, United States of America
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2
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Zhang S, Jia X, Dai H, Zhu X, Song W, Bian S, Wu H, Chen S, Tang Y, Chen J, Jin C, Zhou M, Xie H, Zheng S, Song P. SERPINE2 promotes liver cancer metastasis by inhibiting c-Cbl-mediated EGFR ubiquitination and degradation. Cancer Commun (Lond) 2024; 44:384-407. [PMID: 38407942 PMCID: PMC10958675 DOI: 10.1002/cac2.12527] [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: 08/07/2023] [Revised: 02/03/2024] [Accepted: 02/08/2024] [Indexed: 02/27/2024] Open
Abstract
BACKGROUND Liver cancer is a malignancy with high morbidity and mortality rates. Serpin family E member 2 (SERPINE2) has been reported to play a key role in the metastasis of many tumors. In this study, we aimed to investigate the potential mechanism of SERPINE2 in liver cancer metastasis. METHODS The Cancer Genome Atlas database (TCGA), including DNA methylation and transcriptome sequencing data, was utilized to identify the crucial oncogene associated with DNA methylation and cancer progression in liver cancer. Data from the TCGA and RNA sequencing for 94 pairs of liver cancer tissues were used to explore the correlation between SERPINE2 expression and clinical parameters of patients. DNA methylation sequencing was used to detect the DNA methylation levels in liver cancer tissues and cells. RNA sequencing, cytokine assays, immunoprecipitation (IP) and mass spectrometry (MS) assays, protein stability assays, and ubiquitination assays were performed to explore the regulatory mechanism of SERPINE2 in liver cancer metastasis. Patient-derived xenografts and tumor organoid models were established to determine the role of SERPINE2 in the treatment of liver cancer using sorafenib. RESULTS Based on the public database screening, SERPINE2 was identified as a tumor promoter regulated by DNA methylation. SERPINE2 expression was significantly higher in liver cancer tissues and was associated with the dismal prognosis in patients with liver cancer. SERPINE2 promoted liver cancer metastasis by enhancing cell pseudopodia formation, cell adhesion, cancer-associated fibroblast activation, extracellular matrix remodeling, and angiogenesis. IP/MS assays confirmed that SERPINE2 activated epidermal growth factor receptor (EGFR) and its downstream signaling pathways by interacting with EGFR. Mechanistically, SERPINE2 inhibited EGFR ubiquitination and maintained its protein stability by competing with the E3 ubiquitin ligase, c-Cbl. Additionally, EGFR was activated in liver cancer cells after sorafenib treatment, and SERPINE2 knockdown-induced EGFR downregulation significantly enhanced the therapeutic efficacy of sorafenib against liver cancer. Furthermore, we found that SERPINE2 knockdown also had a sensitizing effect on lenvatinib treatment. CONCLUSIONS SERPINE2 promoted liver cancer metastasis by preventing EGFR degradation via c-Cbl-mediated ubiquitination, suggesting that inhibition of the SERPINE2-EGFR axis may be a potential target for liver cancer treatment.
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3
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Ren JG, Xing B, Lv K, O’Keefe RA, Wu M, Wang R, Bauer KM, Ghazaryan A, Burslem GM, Zhang J, O’Connell RM, Pillai V, Hexner EO, Philips MR, Tong W. RAB27B controls palmitoylation-dependent NRAS trafficking and signaling in myeloid leukemia. J Clin Invest 2023; 133:e165510. [PMID: 37317963 PMCID: PMC10266782 DOI: 10.1172/jci165510] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 03/24/2023] [Indexed: 06/16/2023] Open
Abstract
RAS mutations are among the most prevalent oncogenic drivers in cancers. RAS proteins propagate signals only when associated with cellular membranes as a consequence of lipid modifications that impact their trafficking. Here, we discovered that RAB27B, a RAB family small GTPase, controlled NRAS palmitoylation and trafficking to the plasma membrane, a localization required for activation. Our proteomic studies revealed RAB27B upregulation in CBL- or JAK2-mutated myeloid malignancies, and its expression correlated with poor prognosis in acute myeloid leukemias (AMLs). RAB27B depletion inhibited the growth of CBL-deficient or NRAS-mutant cell lines. Strikingly, Rab27b deficiency in mice abrogated mutant but not WT NRAS-mediated progenitor cell growth, ERK signaling, and NRAS palmitoylation. Further, Rab27b deficiency significantly reduced myelomonocytic leukemia development in vivo. Mechanistically, RAB27B interacted with ZDHHC9, a palmitoyl acyltransferase that modifies NRAS. By regulating palmitoylation, RAB27B controlled c-RAF/MEK/ERK signaling and affected leukemia development. Importantly, RAB27B depletion in primary human AMLs inhibited oncogenic NRAS signaling and leukemic growth. We further revealed a significant correlation between RAB27B expression and sensitivity to MEK inhibitors in AMLs. Thus, our studies presented a link between RAB proteins and fundamental aspects of RAS posttranslational modification and trafficking, highlighting future therapeutic strategies for RAS-driven cancers.
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Affiliation(s)
- Jian-Gang Ren
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Bowen Xing
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kaosheng Lv
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Biochemistry, School of Medicine at the Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Rachel A. O’Keefe
- Department of Medicine and Perlmutter Cancer Center, New York University Grossman School of Medicine, New York, New York, USA
| | - Mengfang Wu
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ruoxing Wang
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kaylyn M. Bauer
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - Arevik Ghazaryan
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - George M. Burslem
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jing Zhang
- McArdle Laboratory for Cancer Research, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Ryan M. O’Connell
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - Vinodh Pillai
- Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Elizabeth O. Hexner
- Division of Hematology and Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Mark R. Philips
- Department of Medicine and Perlmutter Cancer Center, New York University Grossman School of Medicine, New York, New York, USA
| | - Wei Tong
- Division of Hematology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
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4
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Martinez-Val A, Bekker-Jensen DB, Steigerwald S, Koenig C, Østergaard O, Mehta A, Tran T, Sikorski K, Torres-Vega E, Kwasniewicz E, Brynjólfsdóttir SH, Frankel LB, Kjøbsted R, Krogh N, Lundby A, Bekker-Jensen S, Lund-Johansen F, Olsen JV. Spatial-proteomics reveals phospho-signaling dynamics at subcellular resolution. Nat Commun 2021; 12:7113. [PMID: 34876567 PMCID: PMC8651693 DOI: 10.1038/s41467-021-27398-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 11/12/2021] [Indexed: 12/12/2022] Open
Abstract
Dynamic change in subcellular localization of signaling proteins is a general concept that eukaryotic cells evolved for eliciting a coordinated response to stimuli. Mass spectrometry-based proteomics in combination with subcellular fractionation can provide comprehensive maps of spatio-temporal regulation of protein networks in cells, but involves laborious workflows that does not cover the phospho-proteome level. Here we present a high-throughput workflow based on sequential cell fractionation to profile the global proteome and phospho-proteome dynamics across six distinct subcellular fractions. We benchmark the workflow by studying spatio-temporal EGFR phospho-signaling dynamics in vitro in HeLa cells and in vivo in mouse tissues. Finally, we investigate the spatio-temporal stress signaling, revealing cellular relocation of ribosomal proteins in response to hypertonicity and muscle contraction. Proteomics data generated in this study can be explored through https://SpatialProteoDynamics.github.io .
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Affiliation(s)
- Ana Martinez-Val
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Dorte B Bekker-Jensen
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Evosep Systems, Odense, Denmark
| | - Sophia Steigerwald
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Max Planck Institute of Biochemistry, Department of Proteomics and Signal Transduction, Martinsried, Germany
| | - Claire Koenig
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ole Østergaard
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Adi Mehta
- Department of Immunology, Oslo University Hospital, Rikshospitalet, Postboks 4950, Nydalen, 0424, Oslo, Norway
| | - Trung Tran
- Department of Immunology, Oslo University Hospital, Rikshospitalet, Postboks 4950, Nydalen, 0424, Oslo, Norway
| | - Krzysztof Sikorski
- Department of Immunology, Oslo University Hospital, Rikshospitalet, Postboks 4950, Nydalen, 0424, Oslo, Norway
| | - Estefanía Torres-Vega
- Cardiac Proteomics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ewa Kwasniewicz
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | | | - Lisa B Frankel
- Danish Cancer Society, Copenhagen, Denmark
- Danish Cancer Society Research Center, Copenhagen, Denmark
- Biotech Research and Innovation Centre, University of Copenhagen, Copenhagen, Denmark
| | - Rasmus Kjøbsted
- The August Krogh Section for Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai Krogh
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Alicia Lundby
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Cardiac Proteomics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Simon Bekker-Jensen
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Fridtjof Lund-Johansen
- Department of Immunology, Oslo University Hospital, Rikshospitalet, Postboks 4950, Nydalen, 0424, Oslo, Norway.
| | - Jesper V Olsen
- Novo Nordisk Foundation Center for Protein Research, Proteomics Program, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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5
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Crotchett BLM, Ceresa BP. Knockout of c-Cbl slows EGFR endocytic trafficking and enhances EGFR signaling despite incompletely blocking receptor ubiquitylation. Pharmacol Res Perspect 2021; 9:e00756. [PMID: 33811466 PMCID: PMC8019067 DOI: 10.1002/prp2.756] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 12/17/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) activity is necessary and sufficient for corneal epithelial homeostasis. However, the addition of exogenous Epidermal Growth Factor (EGF) does not reliably restore the corneal epithelium when wounded. This is likely due to high levels of endogenous EGF in tear fluid as well as desensitization of the EGFR following ligand stimulation. We hypothesize that preventing receptor downregulation is an alternative mechanism to enhance EGFR signaling and promote the restoration of compromised corneas. Ligand-dependent EGFR ubiquitylation is associated with the targeted degradation of the receptor. In this manuscript, we determine whether knockout of c-Cbl, an E3 ubiquitin ligase that ubiquitylates the EGFR, is sufficient to prolong EGFR phosphorylation and sustain signaling. Using CRISPR/Cas9 gene editing, we generated immortalized human corneal epithelial (hTCEpi) cells lacking c-Cbl. Knockout (KO) cells expressed the other E3 ligases at the same levels as the control cells, indicating other E3 ligases were not up-regulated. As compared to the control cells, EGF-stimulated EGFR ubiquitylation was reduced in KO cells, but not completely abolished. Similarly, EGF:EGFR trafficking was slowed, with a 35% decrease in the rate of endocytosis and a twofold increase in the receptor half-life. This resulted in a twofold increase in the magnitude of EGFR phosphorylation, with no change in duration. Conversely, Mitogen Activating Protein Kinase (MAPK) phosphorylation did not increase in magnitude but was sustained for 2-3 h as compared to control cells. We propose antagonizing c-Cbl will partially alter receptor ubiquitylation and endocytic trafficking but this is sufficient to enhance downstream signaling.
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Affiliation(s)
- Brandon L M Crotchett
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA
| | - Brian P Ceresa
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA.,Department of Visual Science, University of Louisville, Louisville, KY, USA
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6
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Ahmed SF, Buetow L, Gabrielsen M, Lilla S, Sibbet GJ, Sumpton D, Zanivan S, Hedley A, Clark W, Huang DT. E3 ligase-inactivation rewires CBL interactome to elicit oncogenesis by hijacking RTK-CBL-CIN85 axis. Oncogene 2021; 40:2149-2164. [PMID: 33627783 PMCID: PMC7994203 DOI: 10.1038/s41388-021-01684-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 01/20/2021] [Accepted: 01/26/2021] [Indexed: 01/31/2023]
Abstract
Casitas B-lineage lymphoma (CBL) is a ubiquitin ligase (E3) that becomes activated upon Tyr371-phosphorylation and targets receptor protein tyrosine kinases for ubiquitin-mediated degradation. Deregulation of CBL and its E3 activity is observed in myeloproliferative neoplasms and other cancers, including breast, colon, and prostate cancer. Here, we explore the oncogenic mechanism of E3-inactive CBL mutants identified in myeloproliferative neoplasms. We show that these mutants bind strongly to CIN85 under normal growth conditions and alter the CBL interactome. Lack of E3 activity deregulates CIN85 endosomal trafficking, leading to an altered transcriptome that amplifies signaling events to promote oncogenesis. Disruption of CBL mutant interactions with EGFR or CIN85 reduces oncogenic transformation. Given the importance of the CBL-CIN85 interaction in breast cancers, we examined the expression levels of CIN85, CBL, and the status of Tyr371-phosphorylated CBL (pCBL) in human breast cancer tissue microarrays. Interestingly, pCBL shows an inverse correlation with both CIN85 and CBL, suggesting that high expression of inactivated CBL could coordinate with CIN85 for breast cancer progression. Inhibition of the CBL-CIN85 interaction with a proline-rich peptide of CBL that binds CIN85 reduced the proliferation of MDA-MB-231 cells. Together, these results provide a rationale for exploring the potential of targeting the EGFR-CBL-CIN85 axis in CBL-inactivated mutant cancers.
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Affiliation(s)
- Syed Feroj Ahmed
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - Lori Buetow
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - Mads Gabrielsen
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - Sergio Lilla
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - Gary J Sibbet
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - David Sumpton
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - Sara Zanivan
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Ann Hedley
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - William Clark
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK
| | - Danny T Huang
- Cancer Research UK Beatson Institute, Garscube Estate, Glasgow, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
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7
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Liu J, Yao R, Lu S, Xu R, Zhang H, Wei J, Zhao C, Tang Y, Li C, Liu H, Zhao X, Wei Q, Ma B. Synergistic effect between LH and estrogen in the acceleration of cumulus expansion via GPR30 and EGFR pathways. Aging (Albany NY) 2020; 12:20801-20816. [PMID: 33113510 PMCID: PMC7655205 DOI: 10.18632/aging.104029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Accepted: 07/25/2020] [Indexed: 12/15/2022]
Abstract
The estrogen membrane receptor GPR30 (also known as G-protein coupled receptor 30) has recently been shown to be involved in the regulation of oocyte maturation and cumulus expansion. However, whether GPR30 expression is regulated by gonadotropin stimulation and how it participates in the regulation of the maturation process is still not clear. In this study, we explored the mechanism underlying the synergy between luteinizing hormone and 17β-estradiol (17β-E2) to improve the epidermal growth factor (EGF) response in cumulus oocyte complexes (COCs) during oocyte maturation in mice. The expression and distribution of GPR30, EGFR, and EGF-like growth factors were examined by real-time quantitative PCR, western blot, and immunofluorescence staining. Lyso-Tracker Red labeling was performed to detect the lysosomal activity in follicle granular cells (FGCs). Cumulus expansion of COCs was evaluated after in vitro maturation for 16 h. We found that EGF-like growth factors transmit LH signals to increase GRP30 levels by inhibiting protein degradation in lysosomes. Meanwhile, 17β-E2 stimulates the GPR30 signaling pathway to increase EGF receptor levels, enhancing the response ability of EGF signaling in COCs and thus promoting cumulus expansion. In conclusion, our study reveals the synergistic mechanism between LH and estrogen in the regulation of cumulus expansion during oocyte maturation process.
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Affiliation(s)
- Jie Liu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Ru Yao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Sihai Lu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Rui Xu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Hui Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Juncai Wei
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Chunrui Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Yaju Tang
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Chan Li
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Haokun Liu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Xiaoe Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Qiang Wei
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
| | - Baohua Ma
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100 Shaanxi, China.,Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling 712100, Shaanxi, China
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8
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Hong Y, Keylock A, Jensen B, Jacques TS, Ogunbiyi O, Omoyinmi E, Saunders D, Mallick AA, Tooley M, Newbury-Ecob R, Rankin J, Williams HJ, Ganesan V, Brogan PA, Eleftheriou D. Cerebral arteriopathy associated with heterozygous variants in the casitas B-lineage lymphoma gene. NEUROLOGY-GENETICS 2020; 6:e448. [PMID: 32637631 PMCID: PMC7323481 DOI: 10.1212/nxg.0000000000000448] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 04/28/2020] [Indexed: 11/18/2022]
Abstract
Objective To report a series of patients with cerebral arteriopathy associated with heterozygous variants in the casitas B-lineage lymphoma (CBL) gene and examine the functional role of the identified mutant Cbl protein. We hypothesized that mutated Cbl fails to act as a negative regulator of the RAS-mitogen-activated protein kinases (MAPK) signaling pathway, resulting in enhanced vascular fibroblast proliferation and migration and enhanced angiogenesis and collateral vessel formation. Methods We performed whole-exome sequencing in 11 separate families referred to Great Ormond Street Hospital, London, with suspected genetic cause for clinical presentation with severe progressive cerebral arteriopathy. Results We identified heterozygous variants in the CBL gene in 5 affected cases from 3 families. We show that impaired CBL-mediated degradation of cell surface tyrosine kinase receptors and dysregulated intracellular signaling through the RAS-MAPK pathway contribute to the pathogenesis of the observed arteriopathy. Mutated CBL failed to control the angiogenic signal relay of vascular endothelial growth factor receptor 2, leading to prolonged tyrosine kinase signaling, thus driving angiogenesis and collateral vessel formation. Mutant Cbl promoted myofibroblast migration and proliferation contributing to vascular occlusive disease; these effects were abrogated following treatment with a RAF-RAS-MAPK pathway inhibitor. Conclusions We provide a possible mechanism for the arteriopathy associated with heterozygous CBL variants. Identification of the key role for the RAS-MAPK pathway in CBL-mediated cerebral arteriopathy could facilitate identification of novel or repurposed druggable targets for treating these patients and may also provide therapeutic clues for other cerebral arteriopathies.
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Affiliation(s)
- Ying Hong
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Annette Keylock
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Barbara Jensen
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Thomas S Jacques
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Olumide Ogunbiyi
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Ebun Omoyinmi
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Dawn Saunders
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Andrew A Mallick
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Madeleine Tooley
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Ruth Newbury-Ecob
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Julia Rankin
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Hywel J Williams
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Vijeya Ganesan
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Paul A Brogan
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
| | - Despina Eleftheriou
- UCL Great Ormond Street Institute of Child Health (Y.H., A.K., B.J., T.S.J., E.O., D.S., V.G., P.A.B., D.E.); Histopathology Department (O.O.), Great Ormond Street Hospital, London; Paediatric Neurology Department (A.A.M.), and Genetics Department (M.T., R.N.-E.), Bristol Royal Hospital for Children; Genetics Department (J.R.), Royal Devon and Exeter NHS Foundation Trust, Exeter; Centre for Translational Omics-GOSgene (H.J.W.), UCL GOS Institute of Child Health; and Centre for Adolescent Rheumatology Versus Arthritis (D.E.), London, United Kingdom
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9
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Systematic identification of CDC34 that functions to stabilize EGFR and promote lung carcinogenesis. EBioMedicine 2020; 53:102689. [PMID: 32114396 PMCID: PMC7047192 DOI: 10.1016/j.ebiom.2020.102689] [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: 11/11/2019] [Revised: 02/08/2020] [Accepted: 02/10/2020] [Indexed: 12/24/2022] Open
Abstract
Background How the oncoprotein epidermal growth factor receptor (EGFR) evades proteolytic degradation and accumulates in non-small cell lung cancer (NSCLC) remains unclear, and ubiquitin pathway genes (UPGs) that are critical to NSCLC needs to be systematically identified. Methods A total of 696 UPGs (including E1, E2, E3, and deubiquitinases) were silenced by small interfering RNA (siRNA) library in NSCLC cells, the candidates were verified, and their significance was evaluated in patients with NSCLC. The effects of a candidate gene on EGFR were investigated in vitro and in vivo. Findings We report 31 candidates that are required for cell proliferation, with the E2 ubiquitin conjugase CDC34 as the most significant one. CDC34 is elevated in tumor tissues in 76 of 114 (66.7%) NSCLCs and inversely associated with prognosis, is higher in smoker patients than nonsmoker patients, and is induced by tobacco carcinogens in normal human lung epithelial cells. Forced expression of CDC34 promotes, whereas knockdown of CDC34 inhibits, NSCLC cell proliferation in vitro and in vivo. CDC34 competes with c-Cbl to bind Y1045 to inhibit polyubiquitination and degradation of EGFR. In EGFR-L858R and EGFR-T790M/Del (exon 19)-driven lung tumor growth in mouse models, knockdown of CDC34 significantly inhibits tumor formation. Interpretation These results demonstrate that an E2 enzyme is capable of competing with E3 ligase to stabilize substrates, and CDC34 represents an attractive therapeutic target for NSCLCs. Funding National Key Research and Development Program of China, National Natural Science Foundation of China, and the CAMS Innovation Fund for Medical Sciences.
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10
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Borlak J, Länger F, Chatterji B. Serum proteome mapping of EGF transgenic mice reveal mechanistic biomarkers of lung cancer precursor lesions with clinical significance for human adenocarcinomas. Biochim Biophys Acta Mol Basis Dis 2018; 1864:3122-3144. [PMID: 29960043 DOI: 10.1016/j.bbadis.2018.06.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 06/12/2018] [Accepted: 06/25/2018] [Indexed: 12/18/2022]
Abstract
Atypical adenomatous hyperplasia (AAH) of the lung is a pre-invasive lesion (PL) with high risk of progression to lung cancer (LC). However, the pathways involved are uncertain. We searched for novel mechanistic biomarkers of AAH in an EGF transgenic disease model of lung cancer. Disease regulated proteins were validated by Western immunoblotting and immunohistochemistry (IHC) of control and morphologically altered respiratory epithelium. Translational work involved clinical resection material. Collectively, 68 unique serum proteins were identified by 2DE-MALDI-TOF mass spectrometry and 13 reached statistical significance (p < 0.05). EGF, amphiregulin and the EGFR endosomal sorting protein VPS28 were induced up to 5-fold while IHC confirmed strong induction of these proteins. Furthermore, ApoA1, α-2-macroglobulin, and vitamin-D binding protein were nearly 6- and 2-fold upregulated in AAH; however, ApoA1 was oppositely regulated in LC to evidence disease stage dependent regulation of this tumour suppressor. Conversely, plasminogen and transthyretin were highly significantly repressed by 3- and 20-fold. IHC confirmed induced ApoA1, Fetuin-B and transthyretin expression to influence calcification, inflammation and tumour-infiltrating macrophages. Moreover, serum ApoA4, ApoH and ApoM were 2-, 2- and 6-fold repressed; however tissue ApoM and sphingosine-1-phosphate receptor expression was markedly induced to suggest a critical role of sphingosine-1-phosphate signalling in PL and malignant transformation. Finally, a comparison of three different LC models revealed common and unique serum biomarkers mechanistically linked to EGFR, cMyc and cRaf signalling. Their validation by IHC on clinical resection material established relevance for distinct human lung pathologies. In conclusion, we identified mechanistic biomarker candidates recommended for in-depth clinical evaluation.
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Affiliation(s)
- Jürgen Borlak
- Hannover Medical School, Centre for Pharmacology and Toxicology, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - Florian Länger
- Hannover Medical School, Institute of Pathology, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Bijon Chatterji
- Hannover Medical School, Centre for Pharmacology and Toxicology, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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11
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Critchley WR, Pellet-Many C, Ringham-Terry B, Harrison MA, Zachary IC, Ponnambalam S. Receptor Tyrosine Kinase Ubiquitination and De-Ubiquitination in Signal Transduction and Receptor Trafficking. Cells 2018; 7:E22. [PMID: 29543760 PMCID: PMC5870354 DOI: 10.3390/cells7030022] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 03/09/2018] [Accepted: 03/13/2018] [Indexed: 12/13/2022] Open
Abstract
Receptor tyrosine kinases (RTKs) are membrane-based sensors that enable rapid communication between cells and their environment. Evidence is now emerging that interdependent regulatory mechanisms, such as membrane trafficking, ubiquitination, proteolysis and gene expression, have substantial effects on RTK signal transduction and cellular responses. Different RTKs exhibit both basal and ligand-stimulated ubiquitination, linked to trafficking through different intracellular compartments including the secretory pathway, plasma membrane, endosomes and lysosomes. The ubiquitin ligase superfamily comprising the E1, E2 and E3 enzymes are increasingly implicated in this post-translational modification by adding mono- and polyubiquitin tags to RTKs. Conversely, removal of these ubiquitin tags by proteases called de-ubiquitinases (DUBs) enables RTK recycling for another round of ligand sensing and signal transduction. The endocytosis of basal and activated RTKs from the plasma membrane is closely linked to controlled proteolysis after trafficking and delivery to late endosomes and lysosomes. Proteolytic RTK fragments can also have the capacity to move to compartments such as the nucleus and regulate gene expression. Such mechanistic diversity now provides new opportunities for modulating RTK-regulated cellular responses in health and disease states.
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Affiliation(s)
- William R Critchley
- Endothelial Cell Biology Unit, School of Molecular & Cellular Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Caroline Pellet-Many
- Centre for Cardiovascular Biology & Medicine, Rayne Building, University College London, London WC1E 6PT, UK.
| | - Benjamin Ringham-Terry
- Centre for Cardiovascular Biology & Medicine, Rayne Building, University College London, London WC1E 6PT, UK.
| | | | - Ian C Zachary
- Centre for Cardiovascular Biology & Medicine, Rayne Building, University College London, London WC1E 6PT, UK.
| | - Sreenivasan Ponnambalam
- Endothelial Cell Biology Unit, School of Molecular & Cellular Biology, University of Leeds, Leeds LS2 9JT, UK.
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12
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Cheng CC, Chou KF, Wu CW, Su NW, Peng CL, Su YW, Chang J, Ho AS, Lin HC, Chen CGS, Yang BL, Chang YC, Chiang YW, Lim KH, Chang YF. EGFR-mediated interleukin enhancer-binding factor 3 contributes to formation and survival of cancer stem-like tumorspheres as a therapeutic target against EGFR-positive non-small cell lung cancer. Lung Cancer 2017; 116:80-89. [PMID: 29413056 DOI: 10.1016/j.lungcan.2017.12.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 12/26/2017] [Accepted: 12/28/2017] [Indexed: 12/19/2022]
Abstract
OBJECTIVES YM155, an inhibitor of interleukin enhancer-binding factor 3 (ILF3), significantly suppresses cancer stemness property, implying that ILF3 contributes to cell survival of cancer stem cells. However, the molecular function of ILF3 inhibiting cancer stemness remains unclear. This study aimed to uncover the potential function of ILF3 involving in cell survival of epidermal growth factor receptor (EGFR)-positive lung stem-like cancer, and to investigate the potential role to improve the efficacy of anti-EGFR therapeutics. MATERIALS AND METHODS The association of EGFR and ILF3 in expression and regulations was first investigated in this study. Lung cancer A549 cells with deprivation of ILF3 were created by the gene-knockdown method and then RNAseq was applied to identify the putative genes regulated by ILF3. Meanwhile, HCC827- and A549-derived cancer stem-like cells were used to investigate the role of ILF3 in the formation of cancer stem-like tumorspheres. RESULTS We found that EGFR induced ILF3 expression, and YM155 reduced EGFR expression. The knockdown of ILF3 reduced not only EGFR expression in mRNA and protein levels, but also cell proliferation in vitro and in vivo, demonstrating that ILF3 may play an important role in contributing to cancer cell survival. Moreover, the knockdown and inhibition of ILF3 by shRNA and YM155, respectively, reduced the formation and survival of HCC827- and A549-derived tumorspheres through inhibiting ErbB3 (HER3) expression, and synergized the therapeutic efficacy of afatinib, a tyrosine kinase inhibitor, against EGFR-positive A549 lung cells. CONCLUSION This study demonstrated that ILF3 plays an oncogenic like role in maintaining the EGFR-mediated cellular pathway, and can be a therapeutic target to improve the therapeutic efficacy of afatinib. Our results suggested that YM155, an ILF3 inhibitor, has the potential for utilization in cancer therapy against EGFR-positive lung cancers.
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Affiliation(s)
- Chun-Chia Cheng
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan
| | - Kuei-Fang Chou
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan
| | - Cheng-Wen Wu
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Nai-Wen Su
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan
| | - Cheng-Liang Peng
- Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan
| | - Ying-Wen Su
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan
| | - Jungshan Chang
- Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ai-Sheng Ho
- Division of Gastroenterology, Cheng Hsin General Hospital, Taipei, Taiwan
| | - Huan-Chau Lin
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan
| | - Caleb Gon-Shen Chen
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan
| | - Bi-Ling Yang
- Division of Gastroenterology, Cheng Hsin General Hospital, Taipei, Taiwan
| | - Yu-Cheng Chang
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan
| | - Ya-Wen Chiang
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan
| | - Ken-Hong Lim
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan.
| | - Yi-Fang Chang
- Division of Hematology and Oncology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Laboratory of Good Clinical Research Center, Department of Medical Research, MacKay Memorial Hospital, Tamsui District, New Taipei City, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan.
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13
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Buehler J, Zeltzer S, Reitsma J, Petrucelli A, Umashankar M, Rak M, Zagallo P, Schroeder J, Terhune S, Goodrum F. Opposing Regulation of the EGF Receptor: A Molecular Switch Controlling Cytomegalovirus Latency and Replication. PLoS Pathog 2016; 12:e1005655. [PMID: 27218650 PMCID: PMC4878804 DOI: 10.1371/journal.ppat.1005655] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 05/02/2016] [Indexed: 12/15/2022] Open
Abstract
Herpesviruses persist indefinitely in their host through complex and poorly defined interactions that mediate latent, chronic or productive states of infection. Human cytomegalovirus (CMV or HCMV), a ubiquitous β-herpesvirus, coordinates the expression of two viral genes, UL135 and UL138, which have opposing roles in regulating viral replication. UL135 promotes reactivation from latency and virus replication, in part, by overcoming replication-suppressive effects of UL138. The mechanism by which UL135 and UL138 oppose one another is not known. We identified viral and host proteins interacting with UL138 protein (pUL138) to begin to define the mechanisms by which pUL135 and pUL138 function. We show that pUL135 and pUL138 regulate the viral cycle by targeting that same receptor tyrosine kinase (RTK) epidermal growth factor receptor (EGFR). EGFR is a major homeostatic regulator involved in cellular proliferation, differentiation, and survival, making it an ideal target for viral manipulation during infection. pUL135 promotes internalization and turnover of EGFR from the cell surface, whereas pUL138 preserves surface expression and activation of EGFR. We show that activated EGFR is sequestered within the infection-induced, juxtanuclear viral assembly compartment and is unresponsive to stress. Intriguingly, these findings suggest that CMV insulates active EGFR in the cell and that pUL135 and pUL138 function to fine-tune EGFR levels at the cell surface to allow the infected cell to respond to extracellular cues. Consistent with the role of pUL135 in promoting replication, inhibition of EGFR or the downstream phosphoinositide 3-kinase (PI3K) favors reactivation from latency and replication. We propose a model whereby pUL135 and pUL138 together with EGFR comprise a molecular switch that regulates states of latency and replication in HCMV infection by regulating EGFR trafficking to fine tune EGFR signaling. Cytomegalovirus, a herpesvirus, persists in its host through complex interactions that mediate latent, chronic or productive states of infection. Defining the mechanistic basis viral persistence is important for defining the costs and possible benefits of viral persistence and to mitigate pathologies associated with reactivation. We have identified two genes, UL135 and UL138, with opposing roles in regulating states of latency and replication. UL135 promotes replication and reactivation from latency, in part, by overcoming suppressive effects of UL138. Intriguingly, pUL135 and pUL138 regulate the viral cycle by targeting the same receptor tyrosine kinase, epidermal growth factor receptor (EGFR). EGFR is a major homeostatic regulator controlling cellular proliferation, differentiation, and survival, making it an ideal target for viruses to manipulate during infection. We show that CMV insulates and regulates EGFR levels and activity by modulating its trafficking. This work defines a molecular switch that regulates latent and replicative states of infection through the modulation of host trafficking and signaling pathways. The regulation of EGFR at the cell surface provides a novel means by which the virus may sense and respond to changes in the host environment to enter into or exit the latent state.
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Affiliation(s)
- Jason Buehler
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
| | - Sebastian Zeltzer
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, United States of America
| | - Justin Reitsma
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Alex Petrucelli
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
| | | | - Mike Rak
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, United States of America
| | - Patricia Zagallo
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
| | - Joyce Schroeder
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, United States of America
- University of Arizona Cancer Center, University of Arizona, Tucson, Arizona, United States of America
| | - Scott Terhune
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Felicia Goodrum
- BIO5 Institute, University of Arizona, Tucson, Arizona, United States of America
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, United States of America
- Department of Immunobiology, University of Arizona, Tucson, Arizona, United States of America
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, United States of America
- University of Arizona Cancer Center, University of Arizona, Tucson, Arizona, United States of America
- * E-mail:
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14
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Martin-Blanco N, Jiménez Teja D, Bretones G, Borroto A, Caraballo M, Screpanti I, León J, Alarcón B, Canelles M. CD3ε recruits Numb to promote TCR degradation. Int Immunol 2015; 28:127-37. [PMID: 26507128 DOI: 10.1093/intimm/dxv060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 10/15/2015] [Indexed: 01/05/2023] Open
Abstract
Modulation of TCR signaling upon ligand binding is achieved by changes in the equilibrium between TCR degradation, recycling and synthesis; surprisingly, the molecular mechanism of such an important process is not fully understood. Here, we describe the role of a new player in the mediation of TCR degradation: the endocytic adaptor Numb. Our data show that Numb inhibition leads to abnormal intracellular distribution and defective TCR degradation in mature T lymphocytes. In addition, we find that Numb simultaneously binds to both Cbl and a site within CD3ε that overlaps with the Nck binding site. As a result, Cbl couples specifically to the CD3ε chain to mediate TCR degradation. The present study unveils a novel role of Numb that lies at the heart of TCR signaling initiation and termination.
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Affiliation(s)
- Nadia Martin-Blanco
- Instituto de Parasitología y Biomedicina, CSIC, P. T. Ciencias de la Salud, 18100 Granada, Spain Centro de Biología Molecular Severo Ochoa, CSIC, Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Daniel Jiménez Teja
- Instituto de Parasitología y Biomedicina, CSIC, P. T. Ciencias de la Salud, 18100 Granada, Spain
| | - Gabriel Bretones
- Departamento de Biología Molecular, Instituto de Biomedicina y Biotecnología de Cantabria, Universidad de Cantabria-CSIC-SODERCAN, Santander, Spain
| | - Aldo Borroto
- Centro de Biología Molecular Severo Ochoa, CSIC, Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Michael Caraballo
- Instituto de Parasitología y Biomedicina, CSIC, P. T. Ciencias de la Salud, 18100 Granada, Spain
| | - Isabella Screpanti
- Laboratory of Molecular Pathology, Department of Experimental Medicine, Sapienza University of Rome, Viale Regina Elena, 324, 00161 Rome, Italy
| | - Javier León
- Departamento de Biología Molecular, Instituto de Biomedicina y Biotecnología de Cantabria, Universidad de Cantabria-CSIC-SODERCAN, Santander, Spain
| | - Balbino Alarcón
- Centro de Biología Molecular Severo Ochoa, CSIC, Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Matilde Canelles
- Instituto de Parasitología y Biomedicina, CSIC, P. T. Ciencias de la Salud, 18100 Granada, Spain
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15
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Anděl M, Kléma J, Krejčík Z. Network-constrained forest for regularized classification of omics data. Methods 2015; 83:88-97. [PMID: 25872185 DOI: 10.1016/j.ymeth.2015.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 12/28/2022] Open
Abstract
Contemporary molecular biology deals with wide and heterogeneous sets of measurements to model and understand underlying biological processes including complex diseases. Machine learning provides a frequent approach to build such models. However, the models built solely from measured data often suffer from overfitting, as the sample size is typically much smaller than the number of measured features. In this paper, we propose a random forest-based classifier that reduces this overfitting with the aid of prior knowledge in the form of a feature interaction network. We illustrate the proposed method in the task of disease classification based on measured mRNA and miRNA profiles complemented by the interaction network composed of the miRNA-mRNA target relations and mRNA-mRNA interactions corresponding to the interactions between their encoded proteins. We demonstrate that the proposed network-constrained forest employs prior knowledge to increase learning bias and consequently to improve classification accuracy, stability and comprehensibility of the resulting model. The experiments are carried out in the domain of myelodysplastic syndrome that we are concerned about in the long term. We validate our approach in the public domain of ovarian carcinoma, with the same data form. We believe that the idea of a network-constrained forest can straightforwardly be generalized towards arbitrary omics data with an available and non-trivial feature interaction network. The proposed method is publicly available in terms of miXGENE system (http://mixgene.felk.cvut.cz), the workflow that implements the myelodysplastic syndrome experiments is presented as a dedicated case study.
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Affiliation(s)
- Michael Anděl
- Department of Computer Science, Czech Technical University, Technická 2, Prague, Czech Republic.
| | - Jiří Kléma
- Department of Computer Science, Czech Technical University, Technická 2, Prague, Czech Republic.
| | - Zdeněk Krejčík
- Department of Molecular Genetics, Institute of Hematology and Blood Transfusion, U Nemocnice 1, Prague, Czech Republic.
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Parks EE, Ceresa BP. Cell surface epidermal growth factor receptors increase Src and c-Cbl activity and receptor ubiquitylation. J Biol Chem 2014; 289:25537-45. [PMID: 25074934 PMCID: PMC4162159 DOI: 10.1074/jbc.m114.579581] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/07/2014] [Indexed: 11/06/2022] Open
Abstract
There is an established role for the endocytic pathway in regulation of epidermal growth factor receptor (EGFR) signaling to downstream effectors. However, because ligand-mediated EGFR endocytosis utilizes multiple "moving parts," dissecting the spatial versus temporal contributions has been challenging. Blocking all endocytic trafficking can have unintended effects on other receptors as well as give rise to compensatory mechanisms, both of which impact interpretation of EGFR signaling. To overcome these limitations, we used epidermal growth factor (EGF) conjugated to polystyrene beads (EGF beads). EGF beads simultaneously activate the EGFR while blocking its endocytosis and allow analysis of EGFR signaling from the plasma membrane. Human telomerase immortalized corneal epithelial (hTCEpi) cells were used to model normal epithelial cell biology. In hTCEpi cells, both cell surface and intracellular EGFRs exhibited dose-dependent increases in effector activity after 15 min of ligand stimulation, but only the serine phosphorylation of signal transducer and activator of transcription 3 (STAT3) was statistically significant when accounting for receptor phosphorylation. However, over time with physiological levels of receptor phosphorylation, cell surface receptors produced either enhanced or sustained mitogen-activated protein kinase kinase (MEK), Casitas B-lineage lymphoma (c-Cbl), and the pro-oncogene Src activity. These increases in effector communication by cell surface receptors resulted in an increase in EGFR ubiquitylation with sustained ligand incubation. Together, these data indicate that spatial regulation of EGFR signaling may be an important regulatory mechanism in receptor down-regulation.
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Affiliation(s)
- Eileen E Parks
- From the Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
| | - Brian P Ceresa
- From the Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
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17
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Rush JS, Boeving MA, Berry WL, Ceresa BP. Antagonizing c-Cbl enhances EGFR-dependent corneal epithelial homeostasis. Invest Ophthalmol Vis Sci 2014; 55:4691-9. [PMID: 24985478 DOI: 10.1167/iovs.14-14133] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
PURPOSE In many cell types, the E3 ubiquitin ligase, c-Cbl, induces ligand-dependent ubiquitylation of the epidermal growth factor receptor (EGFR) and targets the receptor for lysosomal degradation. The goal of this study was to determine whether c-Cbl is a negative regulator of EGFR in the corneal epithelium and if it can be inhibited to promote corneal epithelial homeostasis. METHODS Expression and activity of c-Cbl were blocked in immortalized human corneal epithelial cells (hTCEpi) using RNAi and pharmacological agents ([4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo-d-3,4-pyrimidine] or PP1). Following c-Cbl inhibition, cells were assessed for ligand-dependent receptor ubiquitylation, receptor phosphorylation, and in vitro wound healing. Subsequent experiments used PP1 in hTCEpi cells and monitored in vivo murine corneal epithelial wound healing. RESULTS Knockdown and inhibition of c-Cbl decreased ligand-dependent ubiquitylation of the EGFR and prolonged receptor activity as measured by tyrosine phosphorylation. Further, these treatments also increased the extent of ligand-dependent corneal epithelial wound healing in vitro and in vivo. CONCLUSION Manipulating the duration of EGFR activity can enhance the rate of restoration of the corneal epithelial layer. Based on our findings, c-Cbl is a new therapeutic target to enhance EGFR-mediated corneal epithelial homeostasis that bypasses the limitations of previous approaches.
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Affiliation(s)
- Jamie S Rush
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, United States
| | - Michael A Boeving
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma, United States
| | - William L Berry
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma, United States
| | - Brian P Ceresa
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, United States Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma, United States
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18
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Magi S, Saeki Y, Kasamatsu M, Tashiro E, Imoto M. Chemical genomic-based pathway analyses for epidermal growth factor-mediated signaling in migrating cancer cells. PLoS One 2014; 9:e96776. [PMID: 24820097 PMCID: PMC4018296 DOI: 10.1371/journal.pone.0096776] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 04/11/2014] [Indexed: 12/20/2022] Open
Abstract
To explore the diversity and consistency of the signaling pathways that regulate tumor cell migration, we chose three human tumor cell lines that migrated after treatment with EGF. We then quantified the effect of fifteen inhibitors on the levels of expression or the phosphorylation levels of nine proteins that were induced by EGF stimulation in each of these cell lines. Based on the data obtained in this study and chemical-biological assumptions, we deduced cell migration pathways in each tumor cell line, and then compared them. As a result, we found that both the MEK/ERK and JNK/c-Jun pathways were activated in all three migrating cell lines. Moreover, GSK-3 and p38 were found to regulate PI3K/Akt pathway in only EC109 cells, and JNK was found to crosstalk with p38 and Fos related pathway in only TT cells. Taken together, our analytical system could easily distinguish between the common and cell type-specific pathways responsible for tumor cell migration.
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Affiliation(s)
- Shigeyuki Magi
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa Japan
| | - Yuya Saeki
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa Japan
| | - Masato Kasamatsu
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa Japan
| | - Etsu Tashiro
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa Japan
| | - Masaya Imoto
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa Japan
- * E-mail:
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Veselits M, Tanaka A, Lipkowitz S, O'Neill S, Sciammas R, Finnegan A, Zhang J, Clark MR. Recruitment of Cbl-b to B cell antigen receptor couples antigen recognition to Toll-like receptor 9 activation in late endosomes. PLoS One 2014; 9:e89792. [PMID: 24651487 PMCID: PMC3961229 DOI: 10.1371/journal.pone.0089792] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 01/27/2014] [Indexed: 12/21/2022] Open
Abstract
Casitas B-lineage lymphoma-b (Cbl-b) is a ubiquitin ligase (E3) that modulates signaling by tagging molecules for degradation. It is a complex protein with multiple domains and binding partners that are not involved in ubiquitinating substrates. Herein, we demonstrate that Cbl-b, but not c-Cbl, is recruited to the clustered B cell antigen receptor (BCR) and that Cbl-b is required for entry of endocytosed BCRs into late endosomes. The E3 activity of Cbl-b is not necessary for BCR endocytic trafficking. Rather, the ubiquitin associated (UBA) domain is required. Furthermore, the Cbl-b UBA domain is sufficient to confer the receptor trafficking functions of Cbl-b on c-Cbl. Cbl-b is also required for entry of the Toll-like receptor 9 (TLR9) into late endosomes and for the in vitro activation of TLR9 by BCR-captured ligands. These data indicate that Cbl-b acts as a scaffolding molecule to coordinate the delivery of the BCR and TLR9 into subcellular compartments required for productively delivering BCR-captured ligands to TLR9.
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Affiliation(s)
- Margaret Veselits
- Section of Rheumatology, Department of Medicine and Knapp Center for Lupus and Immunological Research, University of Chicago, Chicago, Illinois, United States of America
| | - Azusa Tanaka
- Section of Rheumatology, Department of Medicine and Knapp Center for Lupus and Immunological Research, University of Chicago, Chicago, Illinois, United States of America
| | - Stanley Lipkowitz
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Shannon O'Neill
- Integrated Department of Immunology, National Jewish Medical and Research Center and University of Colorado and Health Sciences Center, Denver, Colorado, United States of America
| | - Roger Sciammas
- Section of Rheumatology, Department of Medicine and Knapp Center for Lupus and Immunological Research, University of Chicago, Chicago, Illinois, United States of America
| | - Alison Finnegan
- Department of Immunology and Microbiology, and Department of Internal Medicine, Section of Rheumatology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Jian Zhang
- Section of Nephrology, Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Marcus R. Clark
- Section of Rheumatology, Department of Medicine and Knapp Center for Lupus and Immunological Research, University of Chicago, Chicago, Illinois, United States of America
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Dutta D, Chakraborty S, Bandyopadhyay C, Valiya Veettil M, Ansari MA, Singh VV, Chandran B. EphrinA2 regulates clathrin mediated KSHV endocytosis in fibroblast cells by coordinating integrin-associated signaling and c-Cbl directed polyubiquitination. PLoS Pathog 2013; 9:e1003510. [PMID: 23874206 PMCID: PMC3715429 DOI: 10.1371/journal.ppat.1003510] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 06/06/2013] [Indexed: 12/22/2022] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) interacts with human dermal endothelial cell surface tyrosine kinase EphrinA2 (EphA2) and integrins (α3β1 and αVβ3) in the lipid raft (LR) region, and EphA2 regulates macropinocytic virus entry by coordinating integrin-c-Cbl associated signaling. In contrast, KSHV enters human foreskin fibroblast (HFF) cells by LR-independent clathrin mediated endocytosis. The present studies conducted to identify the key molecules regulating KSHV entry in HFF cells showed that KSHV induces association with integrins (αVβ5, αVβ3 and α3β1) and EphA2 in non-LR regions early during infection and activates EphA2, which in turn associates with phosphorylated c-Cbl, myosin IIA, FAK, Src, and PI3-K, as well as clathrin and its adaptor AP2 and effector Epsin-15 proteins. EphA2 knockdown significantly reduced these signal inductions, virus internalization and gene expression. c-Cbl knockdown ablated the c-Cbl mediated K63 type polyubiquitination of EphA2 and clathrin association with EphA2 and KSHV. Mutations in EphA2's tyrosine kinase domain (TKD) or sterile alpha motif (SAM) abolished its interaction with c-Cbl. Mutations in tyrosine kinase binding (TKB) or RING finger (RF) domains of c-Cbl resulted in very poor association of c-Cbl with EphA2 and decreased EphA2 polyubiquitination. These studies demonstrated the contributions of these domains in EphA2 and c-Cbl association, EphA2 polyubiquitination and virus-EphA2 internalization. Collectively, these results revealed for the first time that EphA2 influences the tyrosine phosphorylation of clathrin, the role of EphA2 in clathrin mediated endocytosis of a virus, and c-Cbl mediated EphA2 polyubiquitination directing KSHV entry in HFF cells via coordinated signal induction and progression of endocytic events, all of which suggest that targeting EphA2 and c-Cbl could block KSHV entry and infection.
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Affiliation(s)
- Dipanjan Dutta
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Sayan Chakraborty
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Chirosree Bandyopadhyay
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Mohanan Valiya Veettil
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Mairaj Ahmed Ansari
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Vivek Vikram Singh
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
| | - Bala Chandran
- H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, United States of America
- * E-mail:
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21
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Melone MA, Calarco A, Petillo O, Margarucci S, Colucci-D'Amato L, Galderisi U, Koverech G, Peluso G. Mutant huntingtin regulates EGF receptor fate in non-neuronal cells lacking wild-type protein. Biochim Biophys Acta Mol Basis Dis 2013; 1832:105-13. [DOI: 10.1016/j.bbadis.2012.09.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 08/10/2012] [Accepted: 09/04/2012] [Indexed: 12/30/2022]
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Abstract
Excessive signaling by receptor tyrosine kinases (RTKs) can cause cancer. What molecular mechanisms normally control RTK signaling? Are they defective in tumors? If so, should therapeutics be developed to restore particular regulatory pathways to cancer cells? These questions have been approached through mechanistic studies of a prototypical RTK, the epidermal growth factor receptor (EGFR). EGFR signaling is mediated and regulated by both signaling and trafficking effectors. The amplitude of receptor-proximal signals changes as EGFRs move along the degradative trafficking pathway from the cell surface, to endosomes, and into lysosomes. To optimize therapeutic suppression of receptor oncogenicity, it may be crucial to target EGFRs that are signaling from a specific site in the trafficking pathway. Research suggests that EGFRs at the plasma membrane produce the bulk of the global transcriptional response to EGF. EGFRs localized between the internalization and early endosome fusion stages of the pathway enrich the expression of transcripts associated with cancer. EGFRs at later trafficking checkpoints controlled by the endosomal sorting complex required for transport (ESCRT) complexes II and III do not contribute substantially to the EGFR-mediated transcriptional response. These results suggest that therapeutics targeting the receptors at the earliest stages of degradative trafficking might be most effective.
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Affiliation(s)
- Nancy L Lill
- Department of Pathology and the OSU Comprehensive Cancer Center, Ohio State University, Columbus, OH 43210, USA.
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Schroeder B, Srivatsan S, Shaw A, Billadeau D, McNiven MA. CIN85 phosphorylation is essential for EGFR ubiquitination and sorting into multivesicular bodies. Mol Biol Cell 2012; 23:3602-11. [PMID: 22833562 PMCID: PMC3442408 DOI: 10.1091/mbc.e11-08-0666] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
This study provides new insights into the mechanisms by which CIN85 regulates targeting of the EGF receptor for degradation. It is the first to demonstrate that CIN85 is phosphorylated by src, phosphorylation of CIN85 is essential for ubiquitinylation of the EGFR, and CIN85 mediates EGFR sequestration into intraluminal vesicles. Ubiquitination of the epidermal growth factor receptor (EGFR) by cbl and its cognate adaptor cbl-interacting protein of 85 kDa (CIN85) is known to play an essential role in directing this receptor to the lysosome for degradation. The mechanisms by which this ubiquitin modification is regulated are not fully defined, nor is it clear where this process occurs. In this study we show that EGFR activation leads to a pronounced src-mediated tyrosine phosphorylation of CIN85 that subsequently influences EGFR ubiquitination. Of importance, phospho-CIN85 interacts with the Rab5-positive endosome, where it mediates the sequestration of the ubiquitinated receptor into multivesicular bodies (MVBs) for subsequent degradation. These findings provide novel insights into how src- kinase–based regulation of a cbl adaptor regulates the fate of the EGFR.
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Affiliation(s)
- Barbara Schroeder
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
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Gui A, Kobayashi A, Motoyama H, Kitazawa M, Takeoka M, Miyagawa S. Impaired degradation followed by enhanced recycling of epidermal growth factor receptor caused by hypo-phosphorylation of tyrosine 1045 in RBE cells. BMC Cancer 2012; 12:179. [PMID: 22591401 PMCID: PMC3476963 DOI: 10.1186/1471-2407-12-179] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 04/25/2012] [Indexed: 02/01/2023] Open
Abstract
Background Since cholangiocarcinoma has a poor prognosis, several epidermal growth factor receptor (EGFR)-targeted therapies with antibody or small molecule inhibitor treatment have been proposed. However, their effect remains limited. The present study sought to understand the molecular genetic characteristics of cholangiocarcinoma related to EGFR, with emphasis on its degradation and recycling. Methods We evaluated EGFR expression and colocalization by immunoblotting and immunofluorescence, cell surface EGFR expression by fluorescence-activated cell sorting (FACS), and EGFR ubiquitination and protein binding by immunoprecipitation in the human cholangiocarcinoma RBE and immortalized cholangiocyte MMNK-1 cell lines. Monensin treatment and Rab11a depletion by siRNA were adopted for inhibition of EGFR recycling. Results Upon stimulation with EGF, ligand-induced EGFR degradation was impaired and the expression of phospho-tyrosine 1068 and phospho-p44/42 MAPK was sustained in RBE cells as compared with MMNK-1 cells. In RBE cells, the process of EGFR sorting for lysosomal degradation was blocked at the early endosome stage, and non-degradated EGFR was recycled to the cell surface. A disrupted association between EGFR and the E3 ubiquitin ligase c-Cbl, as well as hypo-phosphorylation of EGFR at tyrosine 1045 (Tyr1045), were also observed in RBE cells. Conclusion In RBE cells, up-regulation of EGFR Tyr1045 phosphorylation is a potentially useful molecular alteration in EGFR-targeted therapy. The combination of molecular-targeted therapy determined by the characteristics of individual EGFR phosphorylation events and EGFR recycling inhibition show promise in future treatments of cholangiocarcinoma.
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Affiliation(s)
- Anping Gui
- First Department of Surgery, Shinshu University School of Medicine, Asahi, Matsumoto, Nagano, Japan
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25
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Suppression of EGFR endocytosis by dynamin depletion reveals that EGFR signaling occurs primarily at the plasma membrane. Proc Natl Acad Sci U S A 2012; 109:4419-24. [PMID: 22371560 DOI: 10.1073/pnas.1200164109] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The role of endocytosis in the control of EGF receptor (EGFR) activation and cell signaling was explored by using mouse fibroblasts in which dynamin was conditionally depleted. Dynamin is a GTPase shown to play an important role in the control clathrin mediated endocytosis of EGFR and other cell surface receptors. In this report, we demonstrate that EGF binding activity and the display of high and low affinity EGFRs on the cell surface are not affected by dynamin depletion. By contrast, dynamin depletion leads to a strong inhibition of EGFR endocytosis, robust enhancement of EGFR autophosphorylation and ubiquitination, and slower kinetics of EGFR degradation. Surprisingly, MAPK stimulation induced by either low or high EGF concentrations is not affected by dynamin depletion. While a similar initial Akt response is detected in control or dynamin depleted fibroblasts, a somewhat more sustained Akt stimulation is detected in the dynamin depleted cells. These experiments demonstrate that dynamin-mediated endocytosis leads to attenuation of EGFR activation and degradation and that stimulation of the MAPK response and Akt activation are primarily mediated by activated EGFR located in the plasma membrane.
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Abstract
Hepatitis C virus (HCV) leads to progressive liver disease and hepatocellular carcinoma. Current treatments are only partially effective, and new therapies targeting viral and host pathways are required. Virus entry into a host cell provides a conserved target for therapeutic intervention. Tetraspanin CD81, scavenger receptor class B member I, and the tight-junction proteins claudin-1 and occludin have been identified as essential entry receptors. Limited information is available on the role of receptor trafficking in HCV entry. We demonstrate here that anti-CD81 antibodies inhibit HCV infection at late times after virus internalization, suggesting a role for intracellular CD81 in HCV infection. Several tetraspanins have been reported to internalize via motifs in their C-terminal cytoplasmic domains; however, CD81 lacks such motifs, leading several laboratories to suggest a limited role for CD81 endocytosis in HCV entry. We demonstrate CD81 internalization via a clathrin- and dynamin-dependent process, independent of its cytoplasmic domain, suggesting a role for associated partner proteins in regulating CD81 trafficking. Live cell imaging demonstrates CD81 and claudin-1 coendocytosis and fusion with Rab5 expressing endosomes, supporting a role for this receptor complex in HCV internalization. Receptor-specific antibodies and HCV particles increase CD81 and claudin-1 endocytosis, supporting a model wherein HCV stimulates receptor trafficking to promote particle internalization.
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Dou H, Buetow L, Hock A, Sibbet GJ, Vousden KH, Huang DT. Structural basis for autoinhibition and phosphorylation-dependent activation of c-Cbl. Nat Struct Mol Biol 2012; 19:184-92. [PMID: 22266821 PMCID: PMC3880865 DOI: 10.1038/nsmb.2231] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Accepted: 12/19/2011] [Indexed: 12/12/2022]
Abstract
Cbls are RING ubiquitin ligases that attenuate receptor tyrosine kinase (RTK) signal transduction. Cbl ubiquitination activity is stimulated by phosphorylation of a linker helix region (LHR) tyrosine residue. To elucidate the mechanism of activation, we determined the structures of human CBL, a CBL-substrate peptide complex and a phosphorylated-Tyr371-CBL-E2-substrate peptide complex, and we compared them with the known structure of a CBL-E2-substrate peptide complex. Structural and biochemical analyses show that CBL adopts an autoinhibited RING conformation, where the RING's E2-binding surface associates with CBL to reduce E2 affinity. Tyr371 phosphorylation activates CBL by inducing LHR conformational changes that eliminate autoinhibition, flip the RING domain and E2 into proximity of the substrate-binding site and transform the RING domain into an enhanced E2-binding module. This activation is required for RTK ubiquitination. Our results present a mechanism for regulation of c-Cbl's activity by autoinhibition and phosphorylation-induced activation.
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Affiliation(s)
- Hao Dou
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, United Kingdom
| | - Lori Buetow
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, United Kingdom
| | - Andreas Hock
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, United Kingdom
| | - Gary J Sibbet
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, United Kingdom
| | - Karen H Vousden
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, United Kingdom
| | - Danny T Huang
- The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Glasgow, G61 1BD, United Kingdom
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Gailite I, Egger-Adam D, Wodarz A. The phosphoinositide-associated protein Rush hour regulates endosomal trafficking in Drosophila. Mol Biol Cell 2011; 23:433-47. [PMID: 22160599 PMCID: PMC3268723 DOI: 10.1091/mbc.e11-02-0154] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Endocytosis regulates multiple cellular processes, including the protein composition of the plasma membrane, intercellular signaling, and cell polarity. We have identified the highly conserved protein Rush hour (Rush) and show that it participates in the regulation of endocytosis. Rush localizes to endosomes via direct binding of its FYVE (Fab1p, YOTB, Vac1p, EEA1) domain to phosphatidylinositol 3-phosphate. Rush also directly binds to Rab GDP dissociation inhibitor (Gdi), which is involved in the activation of Rab proteins. Homozygous rush mutant flies are viable but show genetic interactions with mutations in Gdi, Rab5, hrs, and carnation, the fly homologue of Vps33. Overexpression of Rush disrupts progression of endocytosed cargo and increases late endosome size. Lysosomal marker staining is decreased in Rush-overexpressing cells, pointing to a defect in the transition between late endosomes and lysosomes. Rush also causes formation of endosome clusters, possibly by affecting fusion of endosomes via an interaction with the class C Vps/homotypic fusion and vacuole protein-sorting (HOPS) complex. These results indicate that Rush controls trafficking from early to late endosomes and from late endosomes to lysosomes by modulating the activity of Rab proteins.
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Affiliation(s)
- Ieva Gailite
- Stammzellbiologie, Abteilung Anatomie und Zellbiologie, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
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Malerød L, Pedersen NM, Sem Wegner CE, Lobert VH, Leithe E, Brech A, Rivedal E, Liestøl K, Stenmark H. Cargo-dependent degradation of ESCRT-I as a feedback mechanism to modulate endosomal sorting. Traffic 2011; 12:1211-26. [PMID: 21564451 DOI: 10.1111/j.1600-0854.2011.01220.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ligand-mediated lysosomal degradation of growth factor receptors, mediated by the endosomal sorting complex required for transport (ESCRT) machinery, is a mechanism that attenuates the cellular response to growth factors. In this article, we present a novel regulatory mechanism that involves ligand-mediated degradation of a key component of the sorting machinery itself. We have investigated the endosomal localization of subunits of the four ESCRTs-Hrs (ESCRT-0), Tsg101 (ESCRT-I), EAP30/Vps22 (ESCRT-II) and charged multivesicular body protein 3/Vps24 (ESCRT-III). All the components were detected on the limiting membrane of multivesicular endosomes (MVEs). Surprisingly, however, Tsg101 and other ESCRT-I subunits were also detected within intraluminal vesicles (ILVs) of MVEs. Tsg101 was sequestered along with cargo during endosomal sorting into ILVs and further degraded in lysosomes. Importantly, ESCRT-mediated downregulation of two distinct cargoes, epidermal growth factor receptor (EGFR) and connexin43, mutually made cells refractory to degradation of the other cargo. Our observations indicate that the degradation of a key ESCRT component along with cargo represents a novel feedback control of endosomal sorting by preventing collateral degradation of cell surface receptors following stimulation of one specific pathway.
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Affiliation(s)
- Lene Malerød
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Montebello, Oslo, Norway
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30
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Sévère N, Miraoui H, Marie PJ. The Casitas B lineage lymphoma (Cbl) mutant G306E enhances osteogenic differentiation in human mesenchymal stromal cells in part by decreased Cbl-mediated platelet-derived growth factor receptor alpha and fibroblast growth factor receptor 2 ubiquitination. J Biol Chem 2011; 286:24443-50. [PMID: 21596750 DOI: 10.1074/jbc.m110.197525] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Human bone marrow-derived mesenchymal stromal cells (hMSCs) have the capacity to differentiate into several cell types including osteoblasts and are therefore an important cell source for bone tissue regeneration. A crucial issue is to identify mechanisms that trigger hMSC osteoblast differentiation to promote osteogenic potential. Casitas B lineage lymphoma (Cbl) is an E3 ubiquitin ligase that ubiquitinates and targets several molecules for degradation. We hypothesized that attenuation of Cbl-mediated degradation of receptor tyrosine kinases (RTKs) may promote osteogenic differentiation in hMSCs. We show here that specific inhibition of Cbl interaction with RTKs using a Cbl mutant (G306E) promotes expression of osteoblast markers (Runx2, alkaline phosphatase, type 1 collagen, osteocalcin) and increases osteogenic differentiation in clonal bone marrow-derived hMSCs and primary hMSCs. Analysis of molecular mechanisms revealed that the Cbl mutant increased PDGF receptor α and FGF receptor 2 but not EGF receptor expression in hMSCs, resulting in increased ERK1/2 and PI3K signaling. Pharmacological inhibition of FGFR or PDGFR abrogated in vitro osteogenesis induced by the Cbl mutant. The data reveal that specific inhibition of Cbl interaction with RTKs promotes the osteogenic differentiation program in hMSCs in part by decreased Cbl-mediated PDGFRα and FGFR2 ubiquitination, providing a novel mechanistic approach targeting Cbl to promote the osteogenic capacity of hMSCs.
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Affiliation(s)
- Nicolas Sévère
- Laboratory of Osteoblast Biology and Pathology, INSERM, U606, Paris F-75475, France
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The human papillomavirus type 16 E5 oncoprotein inhibits epidermal growth factor trafficking independently of endosome acidification. J Virol 2010; 84:10619-29. [PMID: 20686024 DOI: 10.1128/jvi.00831-10] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The human papillomavirus type 16 E5 oncoprotein (16E5) enhances acute, ligand-dependent activation of the epidermal growth factor receptor (EGFR) and concomitantly alkalinizes endosomes, presumably by binding to the 16-kDa "c" subunit of the V-ATPase proton pump (16K) and inhibiting V-ATPase function. However, the relationship between 16K binding, endosome alkalinization, and altered EGFR signaling remains unclear. Using an antibody that we generated against 16K, we found that 16E5 associated with only a small fraction of endogenous 16K in keratinocytes, suggesting that it was unlikely that E5 could significantly affect V-ATPase function by direct inhibition. Nevertheless, E5 inhibited the acidification of endosomes, as determined by a new assay using a biologically active, pH-sensitive fluorescent EGF conjugate. Since we also found that 16E5 did not alter cell surface EGF binding, the number of EGFRs on the cell surface, or the endocytosis of prebound EGF, we postulated that it might be blocking the fusion of early endosomes with acidified vesicles. Our studies with pH-sensitive and -insensitive fluorescent EGF conjugates and fluorescent dextran confirmed that E5 prevented endosome maturation (acidification and enlargement) by inhibiting endosome fusion. The E5-dependent defect in vesicle fusion was not due to detectable disruption of actin, tubulin, vimentin, or cytokeratin filaments, suggesting that membrane fusion was being directly affected rather than vesicle transport. Perhaps most importantly, while bafilomycin A(1) (like E5) binds to 16K and inhibits endosome acidification, it did not mimic the ability of E5 to inhibit endosome enlargement or the trafficking of EGF. Thus, 16E5 alters EGF endocytic trafficking via a pH-independent inhibition of vesicle fusion.
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