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Glogowska A, Stetefeld J, Weber E, Ghavami S, Hoang-Vu C, Klonisch T. Epidermal growth factor cytoplasmic domain affects ErbB protein degradation by the lysosomal and ubiquitin-proteasome pathway in human cancer cells. Neoplasia 2012; 14:396-409. [PMID: 22745586 DOI: 10.1596/neo.111514] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 04/15/2012] [Accepted: 04/16/2012] [Indexed: 12/19/2022]
Abstract
The cytoplasmic domains of EGF-like ligands, including EGF cytoplasmic domain (EGFcyt), have important biological functions. Using specific constructs and peptides of human EGF cytoplasmic domain, we demonstrate that EGFcyt facilitates lysosomal and proteasomal protein degradation, and this coincided with growth inhibition of human thyroid and glioma carcinoma cells. EGFcyt and exon 22-23-encoded peptide (EGF22.23) enhanced procathepsin B (procathB) expression and procathB-mediated lysosomal degradation of EGFR/ErbB1 as determined by inhibitors for procathB and the lysosomal ATPase inhibitor BafA1. Presence of mbEGFctF, EGFcyt, EGF22.23, and exon 23-encoded peptides suppressed the expression of the deubiqitinating enzyme ubiquitin C-terminal hydrolase-L1 (UCH-L1). This coincided with hyperubiquitination of total cellular proteins and ErbB1/2 and reduced proteasome activity. Upon small interfering RNA-mediated silencing of endogenously expressed UCH-L1, a similar hyperubiquitinylation phenotype, reduced ErbB1/2 content, and attenuated growth was observed. The exon 23-encoded peptide region of EGFcyt was important for these biologic actions. Structural homology modeling of human EGFcyt showed that this molecular region formed an exposed surface loop. Peptides derived from this EGFcyt loop structure may aid in the design of novel peptide therapeutics aimed at inhibiting growth of cancer cells.
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Affiliation(s)
- Aleksandra Glogowska
- Department of Human Anatomy and Cell Science, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
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52
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Dynamics of receptor trafficking in tumorigenicity. Trends Cell Biol 2012; 22:231-40. [DOI: 10.1016/j.tcb.2012.02.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 02/01/2012] [Accepted: 02/07/2012] [Indexed: 02/07/2023]
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53
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Polanovski OL, Lebedenko EN, Deyev SM. ERBB oncogene proteins as targets for monoclonal antibodies. BIOCHEMISTRY (MOSCOW) 2012; 77:227-45. [DOI: 10.1134/s0006297912030029] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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54
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Ahmad I, Iwata T, Leung HY. Mechanisms of FGFR-mediated carcinogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:850-60. [PMID: 22273505 DOI: 10.1016/j.bbamcr.2012.01.004] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 01/09/2012] [Accepted: 01/10/2012] [Indexed: 12/11/2022]
Abstract
In this review, the evidence for a role of fibroblast growth factor receptor (FGFR) mediated signalling in carcinogenesis are considered and relevant underlying mechanisms highlighted. FGF signalling mediated by FGFR follows a classic receptor tyrosine kinase signalling pathway and its deregulation at various points of its cascade could result in malignancy. Here we review the accumulating reports that revealed the association of FGF/FGFRs to various types of cancer at a genetic level, along with in vitro and in vivo evidences available so far, which indicates the functional involvement of FGF signalling in tumour formation and progression. An increasing number of drugs against the FGF pathways is currently in clinical testing. We will discuss the strategies for future FGF research in cancer and translational approaches.
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Affiliation(s)
- Imran Ahmad
- Beatson Institute for Cancer Research, Bearsden, Glasgow G61 1BD, UK
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55
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Lefebvre J, Ancot F, Leroy C, Muharram G, Lemière A, Tulasne D. Met degradation: more than one stone to shoot a receptor down. FASEB J 2012; 26:1387-99. [PMID: 22223753 DOI: 10.1096/fj.11-197723] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The receptor tyrosine kinase Met and its high-affinity ligand, the hepatocyte growth factor/scatter factor (HGF/SF), are essential to embryonic development. Deregulation of their signaling is associated with tumorigenesis and metastasis, notably through receptor overexpression. It is thus important to understand the mechanisms controlling Met expression. The ligand-dependent internalization of Met and its subsequent degradation in the lysosomal compartment are well described. This process is known to attenuate downstream Met signaling pathways. Yet internalized Met takes part directly in intracellular signaling by chaperoning signaling factors in the course of its trafficking. Furthermore, recent studies describe various new degradation mechanisms of membrane-anchored Met, involving proteolytic cleavages or association with novel partners. Although all these degradations are ligand-independent, they share, to different extents, some common features with canonical HGF/SF-dependent degradation. Interestingly, activated Met variants display resistance to degradation, suggesting defective degradation is involved in tumorigenesis. Conversely, forced degradation of Met through reinduction of one or more degradation pathways is a promising therapeutic strategy.
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Affiliation(s)
- Jonathan Lefebvre
- CNRS UMR 8161, Institut de Biologie de Lille, Institut Pasteur de Lille, B.P.447, 59021 Lille, France
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56
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Multiple roles for the p85α isoform in the regulation and function of PI3K signalling and receptor trafficking. Biochem J 2011; 441:23-37. [DOI: 10.1042/bj20111164] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The p85α protein is best known as the regulatory subunit of class 1A PI3Ks (phosphoinositide 3-kinases) through its interaction, stabilization and repression of p110-PI3K catalytic subunits. PI3Ks play multiple roles in the regulation of cell survival, signalling, proliferation, migration and vesicle trafficking. The present review will focus on p85α, with special emphasis on its important roles in the regulation of PTEN (phosphatase and tensin homologue deleted on chromosome 10) and Rab5 functions. The phosphatidylinositol-3-phosphatase PTEN directly counteracts PI3K signalling through dephosphorylation of PI3K lipid products. Thus the balance of p85α–p110 and p85α–PTEN complexes determines the signalling output of the PI3K/PTEN pathway, and under conditions of reduced p85α levels, the p85α–PTEN complex is selectively reduced, promoting PI3K signalling. Rab5 GTPases are important during the endocytosis, intracellular trafficking and degradation of activated receptor complexes. The p85α protein helps switch off Rab5, and if defective in this p85α function, results in sustained activated receptor tyrosine kinase signalling and cell transformation through disrupted receptor trafficking. The central role for p85α in the regulation of PTEN and Rab5 has widened the scope of p85α functions to include integration of PI3K activation (p110-mediated), deactivation (PTEN-mediated) and receptor trafficking/signalling (Rab5-mediated) functions, all with key roles in maintaining cellular homoeostasis.
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57
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Sangwan V, Abella J, Lai A, Bertos N, Stuible M, Tremblay ML, Park M. Protein-tyrosine phosphatase 1B modulates early endosome fusion and trafficking of Met and epidermal growth factor receptors. J Biol Chem 2011; 286:45000-13. [PMID: 22045810 DOI: 10.1074/jbc.m111.270934] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The endoplasmic reticulum-localized non-receptor protein-tyrosine phosphatase 1B (PTP1B) is associated with oncogenic, metabolic, and cytokine-related signaling and functionally targets multiple receptor tyrosine kinases (RTKs) for dephosphorylation. Loss of PTP1B activity leads to enhanced ligand-dependent biological activity of the Met RTK among others. Here, we demonstrate that knockdown of PTP1B or expression of a PTP1B trapping aspartic acid-to-alanine substitution (D/A) mutant delayed ligand-induced degradation of the Met and EGF RTKs. Loss of PTP1B function abrogated trafficking of Met and EGF receptor to Rab5- and phosphatidylinositol 3-phosphate (Pl3P)-positive early endosomes and subsequent trafficking through the degradative pathway. Under these conditions, internalization of the Met and EGF receptors was unaltered, suggesting a block at the level of early endosome formation. We show that the N-ethylmaleimide-sensitive factor (NSF), an essential component of the vesicle fusion machinery, was hyperphosphorylated in PTP1B knockdown or PTP1B D/A-expressing cells and was a target for PTP1B. NSF knockdown phenocopied PTP1B knockdown, demonstrating a mechanism through which PTP1B regulates endocytic trafficking. Finally, we show that PTP1B dephosphorylated NSF and that this interaction was required for physiological RTK trafficking and appropriate attenuation of downstream signaling.
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Affiliation(s)
- Veena Sangwan
- Department of Biochemistry, McGill University, Montréal, Québec H3A 1A1, Canada
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58
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Abstract
FGFs (fibroblast growth factors) and their receptors (FGFRs) play essential roles in tightly regulating cell proliferation, survival, migration and differentiation during development and adult life. Deregulation of FGFR signalling, on the other hand, has been associated with many developmental syndromes, and with human cancer. In cancer, FGFRs have been found to become overactivated by several mechanisms, including gene amplification, chromosomal translocation and mutations. FGFR alterations are detected in a variety of human cancers, such as breast, bladder, prostate, endometrial and lung cancers, as well as haematological malignancies. Accumulating evidence indicates that FGFs and FGFRs may act in an oncogenic fashion to promote multiple steps of cancer progression by inducing mitogenic and survival signals, as well as promoting epithelial-mesenchymal transition, invasion and tumour angiogenesis. Therapeutic strategies targeting FGFs and FGFRs in human cancer are therefore currently being explored. In the present review we will give an overview of FGF signalling, the main FGFR alterations found in human cancer to date, how they may contribute to specific cancer types and strategies for therapeutic intervention.
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59
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Avraham R, Yarden Y. Feedback regulation of EGFR signalling: decision making by early and delayed loops. Nat Rev Mol Cell Biol 2011; 12:104-17. [PMID: 21252999 DOI: 10.1038/nrm3048] [Citation(s) in RCA: 494] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human-made information relay systems invariably incorporate central regulatory components, which are mirrored in biological systems by dense feedback and feedforward loops. This type of system control is exemplified by positive and negative feedback loops (for example, receptor endocytosis and dephosphorylation) that enable growth factors and receptor Tyr kinases of the epidermal growth factor receptor (EGFR)/ERBB family to regulate cellular function. Recent studies show that the collection of feedback regulatory loops can perform computational tasks - such as decoding ligand specificity, transforming graded input signals into a digital output and regulating response kinetics. Aberrant signal processing and feedback regulation can lead to defects associated with pathologies such as cancer.
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Affiliation(s)
- Roi Avraham
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 76100, Israel
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60
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Stuible M, Tremblay ML. In control at the ER: PTP1B and the down-regulation of RTKs by dephosphorylation and endocytosis. Trends Cell Biol 2010; 20:672-9. [DOI: 10.1016/j.tcb.2010.08.013] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Revised: 08/10/2010] [Accepted: 08/25/2010] [Indexed: 01/26/2023]
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61
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Haugsten EM, Wiedlocha A, Olsnes S, Wesche J. Roles of fibroblast growth factor receptors in carcinogenesis. Mol Cancer Res 2010; 8:1439-52. [PMID: 21047773 DOI: 10.1158/1541-7786.mcr-10-0168] [Citation(s) in RCA: 229] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The fibroblast growth factor receptors (FGFR) play essential roles both during development and in the adult. Upon ligand binding, FGFRs induce intracellular signaling networks that tightly regulate key biological processes, such as cell proliferation, survival, migration, and differentiation. Deregulation of FGFR signaling can thus alter tissue homeostasis and has been associated with several developmental syndromes as well as with many types of cancer. In human cancer, FGFRs have been found to be deregulated by multiple mechanisms, including aberrant expression, mutations, chromosomal rearrangements, and amplifications. In this review, we will give an overview of the main FGFR alterations described in human cancer to date and discuss their contribution to cancer progression.
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Affiliation(s)
- Ellen Margrethe Haugsten
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, 0310 Oslo, Norway.
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62
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Combination antibody treatment down-regulates epidermal growth factor receptor by inhibiting endosomal recycling. Proc Natl Acad Sci U S A 2010; 107:13252-7. [PMID: 20616078 DOI: 10.1073/pnas.0913476107] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Due to its common dysregulation in epithelial-based cancers and extensive characterization of its role in tumor growth, epidermal growth factor receptor (EGFR) is a highly validated target for anticancer therapies. There has been particular interest in the development of monoclonal antibodies (mAbs) targeting EGFR, resulting in two approved mAb-based drugs and several others in clinical trials. It has recently been reported that treatment with combinations of noncompetitive mAbs can induce receptor clustering, leading to synergistic receptor down-regulation. We elucidate three key aspects of this phenomenon. First, we show that highly potent combinations consisting of two noncompetitive mAbs that target EGFR domain 3 reduce surface receptor levels by up to 80% with a halftime of 0.5-5 h in both normal and transformed human cell lines to an extent inversely proportional to receptor density. Second, we find the mechanism underlying down-regulation to be consistent with recycling inhibition. Third, in contrast to the agonism associated with ligand-induced down-regulation, we demonstrate that mAb-induced down-regulation does not activate EGFR or its downstream effectors and it leads to synergistic reduction in migration and proliferation of cells that secrete autocrine ligand. These new insights will aid in ongoing rational design of EGFR-targeted antibody therapeutics.
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63
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Abella JV, Parachoniak CA, Sangwan V, Park M. Dorsal ruffle microdomains potentiate Met receptor tyrosine kinase signaling and down-regulation. J Biol Chem 2010; 285:24956-67. [PMID: 20529867 DOI: 10.1074/jbc.m110.127985] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dorsal ruffles are apical protrusions induced in response to many growth factors, yet their function is poorly understood. Here we report that downstream from the hepatocyte growth factor (HGF) receptor tyrosine kinase (RTK), Met, dorsal ruffles function as both a localized signaling microdomain as well as a platform from which the Met RTK internalizes and traffics to a degradative compartment. In response to HGF, colonies of epithelial Madin-Darby canine kidney cells form dorsal ruffles for up to 20 min. Met is transcytosed from the basolateral membrane on Rab4 endosomes, to the apical surface where Met, as well as a Met substrate and scaffold protein, Gab1, localize to the dorsal ruffle membrane. This results in activation of downstream signaling proteins, as evidenced by localization of phospho-ERK1/2 to dorsal ruffles. As dorsal ruffles collapse, Met is internalized into EEA1- and Rab5-positive endosomes and is targeted for degradation through delivery to an Hrs-positive sorting compartment. Enhancing HGF-dependent dorsal ruffle formation, through overexpression of Gab1 or activated Pak1 kinase, promotes more efficient degradation of the Met RTK. Conversely, the ablation of dorsal ruffle formation, by pre-treatment with SITS (4-acetamido-4'-isothiocyabatostilbene-2',2-disulfonic acid) or expression of a Gab1 mutant, impairs Met degradation. Taken together, these data support a function for dorsal ruffles as a biologically relevant signaling microenvironment and a mechanism for Met receptor internalization and degradation.
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Affiliation(s)
- Jasmine V Abella
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montréal, Québec H3A 1A1, Canada
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64
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Chamberlain MD, Oberg JC, Furber LA, Poland SF, Hawrysh AD, Knafelc SM, McBride HM, Anderson DH. Deregulation of Rab5 and Rab4 proteins in p85R274A-expressing cells alters PDGFR trafficking. Cell Signal 2010; 22:1562-75. [PMID: 20570729 DOI: 10.1016/j.cellsig.2010.05.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 05/27/2010] [Accepted: 05/30/2010] [Indexed: 01/30/2023]
Abstract
Activated receptor tyrosine kinases recruit many signaling proteins to activate downstream cell proliferation and survival pathways, including phosphatidylinositol 3-kinase (PI3K) consisting of a p85 regulatory protein and a p110 catalytic protein. We have recently shown the p85alpha protein also has in vitro GTPase activating protein (GAP) activity towards Rab5 and Rab4, small GTPases that regulate vesicle trafficking events for activated receptors. Expression of a GAP-defective mutant, p85R274A, resulted in sustained levels of activated platelet-derived growth factor receptors (PDGFRs) and enhanced downstream signaling. In this report we have characterized Rab5- and Rab4-mediated PDGFR trafficking in cells expressing wild type p85 and GAP-defective mutant p85R274A. Wild type p85 overexpressing cells had slower PDGFR trafficking consistent with enhanced GAP activity deactivating Rab5 and Rab4 to block their vesicle trafficking functions. Mutant p85R274A expression increased the internalization rate of PDGFRs, a Rab5-dependent process, without preventing PDGFR ubiquitination. Immunofluorescence studies further demonstrated that p85R274A-expressing cells showed Rab5 accumulation at intracellular locations. Pull-down and FRAP (fluorescence recovery after photobleaching) experiments indicate this is likely membrane-associated Rab5-GTP, sustained due to decreased p85 GAP activity for the p85R274A mutant. These cells also had substantial amounts of activated PDGFRs in Rab4-positive recycling endosomes, a compartment that usually contains primarily deactivated/dephosphorylated receptors. Our results suggest that the PDGFR-associated GAP activity of p85 regulates both Rab5 and Rab4 functions in cells to influence the movement of activated PDGFR through endosomal compartments. Disruption of this regulation by p85R274A expression impacts PDGFR phosphorylation/dephosphorylation, degradation kinetics and downstream signaling by altering the time receptors spend in specific intracellular endosomal compartments. These results demonstrate that the p85alpha protein is an important regulator of Rab-mediated PDGFR trafficking, which significantly impacts receptor signaling and degradation.
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Affiliation(s)
- M Dean Chamberlain
- Cancer Research Unit, Research Division, Saskatchewan Cancer Agency, 20 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 4H4
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65
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Stuible M, Abella JV, Feldhammer M, Nossov M, Sangwan V, Blagoev B, Park M, Tremblay ML. PTP1B targets the endosomal sorting machinery: dephosphorylation of regulatory sites on the endosomal sorting complex required for transport component STAM2. J Biol Chem 2010; 285:23899-907. [PMID: 20504764 DOI: 10.1074/jbc.m110.115295] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dephosphorylation and endocytic down-regulation are distinct processes that together control the signaling output of a variety of receptor tyrosine kinases (RTKs). PTP1B can directly dephosphorylate several RTKs, but it can also promote activation of downstream pathways through largely unknown mechanisms. These positive signaling functions likely contribute to the tumor-promoting effect of PTP1B in mouse cancer models. Here, we have identified STAM2, an endosomal protein involved in sorting activated RTKs for lysosomal degradation, as a substrate of PTP1B. PTP1B interacts with STAM2 at defined phosphotyrosine sites, and knockdown of PTP1B expression augments STAM2 phosphorylation. Intriguingly, manipulating the expression and phosphorylation state of STAM2 did not have a general effect on epidermal growth factor (EGF)-induced EGF receptor trafficking, degradation, or signaling. Instead, phosphorylated STAM2 specifically suppressed Akt activation, and a phosphorylation-deficient STAM2 mutant displayed prolonged localization on endosomes following EGF stimulation. These results reveal a novel link between the dephosphorylation and endocytic machinery and suggest that PTP1B can affect RTK signaling in a previously unrecognized manner.
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Affiliation(s)
- Matthew Stuible
- Rosalind and Morris Goodman Cancer Centre and Departments of Biochemistry and Oncology, McGill University, Montreal, Quebec H3A 1A3, Canada
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66
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Marx C, Held JM, Gibson BW, Benz CC. ErbB2 trafficking and degradation associated with K48 and K63 polyubiquitination. Cancer Res 2010; 70:3709-17. [PMID: 20406983 DOI: 10.1158/0008-5472.can-09-3768] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The overexpressed ErbB2/HER2 receptor is a clinically validated cancer target whose surface localization and internalization mechanisms remain poorly understood. Downregulation of the overexpressed 185-kDa ErbB2 receptor is rapidly (2-6 hours) induced by the HSP90 chaperone inhibitor geldanamycin (GA), whereas its downregulation and lysosomal degradation are more slowly (24 hours) induced by the proteasome inhibitor bortezomib/PS341. In PS341-treated SK-BR-3 cells, overexpressed ErbB2 coprecipitates with the E3 ubiquitin ligase c-Cbl and also with the deubiquitinating enzyme USP9x; moreover, siRNA downregulation of USP9x enhances PS341-induced ErbB2 downregulation. Because polyubiquitin linkages via lysine 48 (K48) or 63 (K63) can differentially address proteins for 26S proteasomal degradation or endosome trafficking to the lysosome, multiple reaction monitoring (MRM)/mass spectrometry (MS) and polyubiquitin linkage-specific antibodies were used to quantitatively track K48-linked and K63-linked ErbB2 polyubiquitination following either GA or PS341 treatment of SK-BR-3 cells. MRM/MS revealed that unlike the rapid, modest (4-fold to 8-fold), and synchronous GA induction of K48 and K63 polyubiquitinated ErbB2, PS341 produces a dramatic (20-fold to 40-fold) sequential increase in polyubiquitinated ErbB2 consistent with K48 polyubiquitination followed by K63 editing. Fluorescence microscopic imaging confirmed that PS341, but not GA, induces colocalization of K48-linked and K63-linked polyubiquitin with perinuclear lysosome-sequestered ErbB2. Thus, ErbB2 surface overexpression and recycling seem to depend on its polyubiquitination and deubiquitination; as well, the contrasting effects of PS341 and GA on ErbB2 receptor localization, polyubiquitination, and degradation point to alternate cytoplasmic trafficking likely regulated by different K48 and K63 polyubiquitin editing mechanisms.
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Affiliation(s)
- Corina Marx
- Buck Institute for Age Research, Novato, California 94945, USA
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67
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Lai AZ, Abella JV, Park M. Crosstalk in Met receptor oncogenesis. Trends Cell Biol 2009; 19:542-51. [PMID: 19758803 DOI: 10.1016/j.tcb.2009.07.002] [Citation(s) in RCA: 159] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 07/16/2009] [Accepted: 07/17/2009] [Indexed: 11/25/2022]
Abstract
The Met receptor tyrosine kinase (RTK) regulates several distinct biological processes, including cell scatter, cell invasion, cell survival and epithelial remodeling. MET is genetically altered through several mechanisms in multiple human cancers; these events are causally related to cancer initiation and progression, identifying Met as a potential therapeutic target. Recent evidence highlights additional roles for Met in cancer through crosstalk with other receptors and cell surface proteins. In this review, we discuss recent progress in our understanding of mechanisms of interaction between Met, the epidermal growth factor receptor family and other cell surface protein families, and how these contribute to signal crosstalk, oncogenesis and drug resistance.
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Affiliation(s)
- Andrea Z Lai
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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