51
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Hamoud N, Tran V, Aimi T, Kakegawa W, Lahaie S, Thibault MP, Pelletier A, Wong GW, Kim IS, Kania A, Yuzaki M, Bouvier M, Côté JF. Spatiotemporal regulation of the GPCR activity of BAI3 by C1qL4 and Stabilin-2 controls myoblast fusion. Nat Commun 2018; 9:4470. [PMID: 30367035 PMCID: PMC6203814 DOI: 10.1038/s41467-018-06897-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 10/05/2018] [Indexed: 11/09/2022] Open
Abstract
Myoblast fusion is tightly regulated during development and regeneration of muscle fibers. BAI3 is a receptor that orchestrates myoblast fusion via Elmo/Dock1 signaling, but the mechanisms regulating its activity remain elusive. Here we report that mice lacking BAI3 display small muscle fibers and inefficient muscle regeneration after cardiotoxin-induced injury. We describe two proteins that repress or activate BAI3 in muscle progenitors. We find that the secreted C1q-like1-4 proteins repress fusion by specifically interacting with BAI3. Using a proteomic approach, we identify Stabilin-2 as a protein that interacts with BAI3 and stimulates its fusion promoting activity. We demonstrate that Stabilin-2 activates the GPCR activity of BAI3. The resulting activated heterotrimeric G-proteins contribute to the initial recruitment of Elmo proteins to the membrane, which are then stabilized on BAI3 through a direct interaction. Collectively, our results demonstrate that the activity of BAI3 is spatiotemporally regulated by C1qL4 and Stabilin-2 during myoblast fusion.
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Affiliation(s)
- Noumeira Hamoud
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Département de Médecine (Programmes de Biologie Moléculaire), Université de Montréal, Montréal, QC, H3T 1J4, Canada
| | - Viviane Tran
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Département de Biochimie, Université de Montréal, Montréal, QC, H3T 1J4, Canada
| | - Takahiro Aimi
- Department of Physiology, Keio University School of Medicine, Tokyo, 160-8582, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JT), Tokyo, 102-0075, Japan
| | - Wataru Kakegawa
- Department of Physiology, Keio University School of Medicine, Tokyo, 160-8582, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JT), Tokyo, 102-0075, Japan
| | - Sylvie Lahaie
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Integrated Program in Neuroscience, McGill University, Montréal, QC, H3A 2B4, Canada
| | - Marie-Pier Thibault
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada
| | - Ariane Pelletier
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada
| | - G William Wong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Center for Metabolism and Obesity Research, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - In-San Kim
- Biomedical Research Institute, Korea Institute Science and Technology, Seoul, 136-791, Republic of Korea.,KU-KIST school, Korea University, Seoul, 136-701, Republic of Korea
| | - Artur Kania
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Integrated Program in Neuroscience, McGill University, Montréal, QC, H3A 2B4, Canada.,Department of Anatomy and Cell Biology, McGill University, Montréal, QC, H3A 1A3, Canada
| | - Michisuke Yuzaki
- Department of Physiology, Keio University School of Medicine, Tokyo, 160-8582, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JT), Tokyo, 102-0075, Japan
| | - Michel Bouvier
- Département de Biochimie, Université de Montréal, Montréal, QC, H3T 1J4, Canada.,Institut de Recherches en Immunologie et Cancérologie (IRIC), Université de Montréal, Montréal, QC, Canada, H3C 3J7
| | - Jean-François Côté
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada. .,Département de Médecine (Programmes de Biologie Moléculaire), Université de Montréal, Montréal, QC, H3T 1J4, Canada. .,Département de Biochimie, Université de Montréal, Montréal, QC, H3T 1J4, Canada. .,Department of Anatomy and Cell Biology, McGill University, Montréal, QC, H3A 1A3, Canada.
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52
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Silencing ELMO3 Inhibits the Growth, Invasion, and Metastasis of Gastric Cancer. BIOMED RESEARCH INTERNATIONAL 2018; 2018:3764032. [PMID: 30345300 PMCID: PMC6174816 DOI: 10.1155/2018/3764032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 09/03/2018] [Indexed: 12/19/2022]
Abstract
ELMO3 is a member of the engulfment and cell motility (ELMO) protein family, which plays a vital role in the process of chemotaxis and metastasis of tumor cells. However, remarkably little is known about the role of ELMO3 in cancer. The present study was conducted to investigate the function and role of ELMO3 in gastric cancer (GC) progression. The expression level of ELMO3 in gastric cancer tissues and cell lines was measured by means of real-time quantitative PCR (qPCR) and Western blot analysis. RNA interference was used to inhibit ELMO3 expression in gastric cancer cells. Then, wound-healing assays, Transwell assays, MTS assays, flow cytometry, and fluorescence microscopy were applied to detect cancer cell migration, cell invasion, cell proliferation, the cell cycle, and F-actin polymerization, respectively. The results revealed that ELMO3 expression in GC tumor tissues was significantly higher than in the paired adjacent tissues. Moreover, knockdown of ELMO3 by a specific siRNA significantly inhibited the processes of cell proliferation, invasion, metastasis, regulation of the cell cycle, and F-actin polymerization. Collectively, the results indicate that ELMO3 participates in the processes of cell growth, invasion, and migration, and ELMO3 is expected to be a potential diagnostic and prognostic marker for GC.
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53
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Caggia S, Chunduri H, Millena AC, Perkins JN, Venugopal SV, Vo BT, Li C, Tu Y, Khan SA. Novel role of Giα2 in cell migration: Downstream of PI3-kinase-AKT and Rac1 in prostate cancer cells. J Cell Physiol 2018; 234:802-815. [PMID: 30078221 DOI: 10.1002/jcp.26894] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 06/13/2018] [Indexed: 12/20/2022]
Abstract
Tumor cell motility is the essential step in cancer metastasis. Previously, we showed that oxytocin and epidermal growth factor (EGF) effects on cell migration in prostate cancer cells require Giα2 protein. In the current study, we investigated the interactions among G-protein coupled receptor (GPCR), Giα2, PI3-kinase, and Rac1 activation in the induction of migratory and invasive behavior by diverse stimuli. Knockdown and knockout of endogenous Giα2 in PC3 cells resulted in attenuation of transforming growth factor β1 (TGFβ1), oxytocin, SDF-1α, and EGF effects on cell migration and invasion. In addition, knockdown of Giα2 in E006AA cells attenuated cell migration and overexpression of Giα2 in LNCaP cells caused significant increase in basal and EGF-stimulated cell migration. Pretreatment of PC3 cells with Pertussis toxin resulted in attenuation of TGFβ1- and oxytocin-induced migratory behavior and PI3-kinase activation without affecting EGF-induced PI3-kinase activation and cell migration. Basal- and EGF-induced activation of Rac1 in PC3 and DU145 cells were not affected in cells after Giα2 knockdown. On the other hand, Giα2 knockdown abolished the migratory capability of PC3 cells overexpressing constitutively active Rac1. The knockdown or knockout of Giα2 resulted in impaired formation of lamellipodia at the leading edge of the migrating cells. We conclude that Giα2 protein acts at two different levels which are both dependent and independent of GPCR signaling to induce cell migration and invasion in prostate cancer cells and its action is downstream of PI3-kinase-AKT-Rac1 axis.
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Affiliation(s)
- Silvia Caggia
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, Georgia
| | - HimaBindu Chunduri
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, Georgia
| | - Ana C Millena
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, Georgia
| | - Jonathan N Perkins
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, Georgia
| | - Smrruthi V Venugopal
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, Georgia
| | - BaoHan T Vo
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Chunliang Li
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Yaping Tu
- Department of Pharmacology, Creighton University School of Medicine, Omaha, Nebraska
| | - Shafiq A Khan
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, Georgia
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54
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Polarized Dock Activity Drives Shh-Mediated Axon Guidance. Dev Cell 2018; 46:410-425.e7. [PMID: 30078728 DOI: 10.1016/j.devcel.2018.07.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 05/18/2018] [Accepted: 07/06/2018] [Indexed: 11/23/2022]
Abstract
In the developing spinal cord, Sonic hedgehog (Shh) attracts commissural axons toward the floorplate. How Shh regulates the cytoskeletal remodeling that underlies growth cone turning is unknown. We found that Shh-mediated growth cone turning requires the activity of Docks, which are unconventional GEFs. Knockdown of Dock3 and 4, or their binding partner ELMO1 and 2, abolished commissural axon attraction by Shh in vitro. Dock3/4 and ELMO1/2 were also required for correct commissural axon guidance in vivo. Polarized Dock activity was sufficient to induce axon turning, indicating that Docks are instructive for axon guidance. Mechanistically, we show that Dock and ELMO interact with Boc, the Shh receptor, and that this interaction is reduced upon Shh stimulation. Furthermore, Shh stimulation translocates ELMO to the growth cone periphery and activates Rac1. This identifies Dock/ELMO as an effector complex of non-canonical Shh signaling and demonstrates the instructive role of GEFs in axon guidance.
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55
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Li W, Tam KMV, Chan WWR, Koon AC, Ngo JCK, Chan HYE, Lau KF. Neuronal adaptor FE65 stimulates Rac1-mediated neurite outgrowth by recruiting and activating ELMO1. J Biol Chem 2018; 293:7674-7688. [PMID: 29615491 DOI: 10.1074/jbc.ra117.000505] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 03/12/2018] [Indexed: 12/25/2022] Open
Abstract
Neurite outgrowth is a crucial process in developing neurons for neural network formation. Understanding the regulatory mechanisms of neurite outgrowth is essential for developing strategies to stimulate neurite regeneration after nerve injury and in neurodegenerative disorders. FE65 is a brain-enriched adaptor that stimulates Rac1-mediated neurite elongation. However, the precise mechanism by which FE65 promotes the process remains elusive. Here, we show that ELMO1, a subunit of ELMO1-DOCK180 bipartite Rac1 guanine nucleotide exchange factor (GEF), interacts with the FE65 N-terminal region. Overexpression of FE65 and/or ELMO1 enhances, whereas knockdown of FE65 or ELMO1 inhibits, neurite outgrowth and Rac1 activation. The effect of FE65 alone or together with ELMO1 is attenuated by an FE65 double mutation that disrupts FE65-ELMO1 interaction. Notably, FE65 is found to activate ELMO1 by diminishing ELMO1 intramolecular autoinhibitory interaction and to promote the targeting of ELMO1 to the plasma membrane, where Rac1 is activated. We also show that FE65, ELMO1, and DOCK180 form a tripartite complex. Knockdown of DOCK180 reduces the stimulatory effect of FE65-ELMO1 on Rac1 activation and neurite outgrowth. Thus, we identify a novel mechanism by which FE65 stimulates Rac1-mediated neurite outgrowth by recruiting and activating ELMO1.
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Affiliation(s)
- Wen Li
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
| | - Ka Ming Vincent Tam
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
| | - Wai Wa Ray Chan
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
| | - Alex Chun Koon
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
| | - Jacky Chi Ki Ngo
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
| | - Ho Yin Edwin Chan
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
| | - Kwok-Fai Lau
- From the School of Life Sciences, Faculty of Science, Chinese University of Hong Kong, Shatin New Territories, Hong Kong
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56
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DNA Methylation Levels of the ELMO Gene Promoter CpG Islands in Human Glioblastomas. Int J Mol Sci 2018; 19:ijms19030679. [PMID: 29495584 PMCID: PMC5877540 DOI: 10.3390/ijms19030679] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/13/2018] [Accepted: 02/23/2018] [Indexed: 02/07/2023] Open
Abstract
Complete surgical resection of glioblastoma is difficult due to the invasive nature of this primary brain tumor, for which the molecular mechanisms behind remain poorly understood. The three human ELMO genes play key roles in cellular motility, and have been linked to metastasis and poor prognosis in other cancer types. The aim of this study was to investigate methylation levels of the ELMO genes and their correlation to clinical characteristics and outcome in patients diagnosed with glioblastoma. To measure DNA methylation levels we designed pyrosequencing assays targeting the promoter CpG island of each the ELMO genes. These were applied to diagnostic tumor specimens from a well-characterized cohort of 121 patients who received standard treatment consisting of surgery, radiation therapy, plus concomitant and adjuvant chemotherapy. The promoter methylation levels of ELMO1 and ELMO2 were generally low, whereas ELMO3 methylation levels were high, in the tumor biopsies. Thirteen, six, and 18 biopsies were defined as aberrantly methylated for ELMO1, ELMO2, and ELMO3, respectively. There were no significant associations between the methylation status of any of the ELMO gene promoter CpG islands and overall survival, progression-free survival, and clinical characteristics of the patients including intracranial tumor location. Therefore, the methylation status of the ELMO gene promoter CpG islands is unlikely to have prognostic value in glioblastoma.
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57
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Acevedo A, González-Billault C. Crosstalk between Rac1-mediated actin regulation and ROS production. Free Radic Biol Med 2018; 116:101-113. [PMID: 29330095 DOI: 10.1016/j.freeradbiomed.2018.01.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 01/03/2018] [Accepted: 01/05/2018] [Indexed: 02/08/2023]
Abstract
The small RhoGTPase Rac1 is implicated in a variety of events related to actin cytoskeleton rearrangement. Remarkably, another event that is completely different from those related to actin regulation has the same relevance; the Rac1-mediated production of reactive oxygen species (ROS) through NADPH oxidases (NOX). Each outcome involves different Rac1 downstream effectors; on one hand, events related to the actin cytoskeleton require Rac1 to bind to WAVEs proteins and PAKs that ultimately promote actin branching and turnover, on the other, NOX-derived ROS production demands active Rac1 to be bound to a cytosolic activator of NOX. How Rac1-mediated signaling ends up promoting actin-related events, NOX-derived ROS, or both is poorly understood. Rac1 regulators, including scaffold proteins, are known to exert tight control over its functions. Hence, evidence of Rac1 regulatory events leading to both actin remodeling and NOX-mediated ROS generation are discussed. Moreover, cellular functions linked to physiological and pathological conditions that exhibit crosstalk between Rac1 outcomes are analyzed, while plausible roles in neuronal functions (and dysfunctions) are highlighted. Together, discussed evidence shed light on cellular mechanisms which requires Rac1 to direct either actin- and/or ROS-related events, helping to understand crucial roles of Rac1 dual functionality.
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Affiliation(s)
- Alejandro Acevedo
- FONDAP Geroscience Center for Brain Health and Metabolism, Santiago, Chile.
| | - Christian González-Billault
- FONDAP Geroscience Center for Brain Health and Metabolism, Santiago, Chile; Department of Biology, Faculty of Sciences, Universidad de Chile, 7800024, Chile; The Buck Institute for Research on Aging, Novato, USA.
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58
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Lawson CD, Ridley AJ. Rho GTPase signaling complexes in cell migration and invasion. J Cell Biol 2018; 217:447-457. [PMID: 29233866 PMCID: PMC5800797 DOI: 10.1083/jcb.201612069] [Citation(s) in RCA: 329] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/23/2017] [Accepted: 11/17/2017] [Indexed: 12/02/2022] Open
Abstract
Cell migration is dependent on the dynamic formation and disassembly of actin filament-based structures, including lamellipodia, filopodia, invadopodia, and membrane blebs, as well as on cell-cell and cell-extracellular matrix adhesions. These processes all involve Rho family small guanosine triphosphatases (GTPases), which are regulated by the opposing actions of guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Rho GTPase activity needs to be precisely tuned at distinct cellular locations to enable cells to move in response to different environments and stimuli. In this review, we focus on the ability of RhoGEFs and RhoGAPs to form complexes with diverse binding partners, and describe how this influences their ability to control localized GTPase activity in the context of migration and invasion.
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Affiliation(s)
- Campbell D Lawson
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, England, UK
| | - Anne J Ridley
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, England, UK
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59
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Liu Y, Zhang X, Yang B, Zhuang H, Guo H, Wei W, Li Y, Chen R, Li Y, Zhang N. Demethylation-Induced Overexpression of Shc3 Drives c-Raf-Independent Activation of MEK/ERK in HCC. Cancer Res 2018; 78:2219-2232. [PMID: 29330146 DOI: 10.1158/0008-5472.can-17-2432] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Revised: 12/14/2017] [Accepted: 01/08/2018] [Indexed: 11/16/2022]
Abstract
Invasion and intrahepatic metastasis are major factors of poor prognosis in patients with hepatocellular carcinoma (HCC). In this study, we show that increased Src homolog and collagen homolog 3 (Shc3) expression in malignant HCC cell lines associate with HCC invasion and metastasis. Shc3 (N-Shc) was significantly upregulated in tumors of 33 HCC patient samples as compared with adjacent normal tissues. Further analysis of 52 HCC patient samples showed that Shc3 expression correlated with microvascular invasion, cancer staging, and poor prognosis. Shc3 interacted with major vault protein, resulting in activation of MEK1/2 and ERK1/2 independently of Shc1 and c-Raf; this interaction consequently induced epithelial-mesenchymal transition and promoted HCC cell proliferation and metastasis. The observed increase in Shc3 levels was due to demethylation of its upstream promoter, which allowed c-Jun binding. In turn, Shc3 expression promoted c-Jun phosphorylation in a positive feedback loop. Analysis of metastasis using a tumor xenograft mouse model further confirmed the role of Shc3 in vivo Taken together, our results indicate the importance of Shc3 in HCC progression and identify Shc3 as a novel biomarker and potential therapeutic target in HCC.Significance: Ectopic expression of Shc3 forms a complex with MVP/MEK/ERK to potentiate ERK activation and plays an important role in sorafinib resistance in HCC. Cancer Res; 78(9); 2219-32. ©2018 AACR.
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Affiliation(s)
- Yun Liu
- Key Laboratory of Breast Cancer Prevention and Therapy, Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China
| | - Xinran Zhang
- Key Laboratory of Breast Cancer Prevention and Therapy, Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China
| | - Baicai Yang
- Key Laboratory of Breast Cancer Prevention and Therapy, Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China
| | - Hao Zhuang
- Key Laboratory of Breast Cancer Prevention and Therapy, Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China.,Department of Hepatic Biliary Pancreatic Surgery, Cancer Hospital Affiliated to Zhengzhou University, Zhengzhou, Henan Province, China
| | - Hua Guo
- Key Laboratory of Breast Cancer Prevention and Therapy, Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China
| | - Wen Wei
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Yuan Li
- Department of Laboratory Animal Sciences, Tianjin Medical University, Tianjin, China
| | - Ruibing Chen
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Yongmei Li
- Department of Pathogen Biology, Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China.
| | - Ning Zhang
- Key Laboratory of Breast Cancer Prevention and Therapy, Laboratory of Cancer Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China.
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60
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Rac1 plays a role in CXCL12 but not CCL3-induced chemotaxis and Rac1 GEF inhibitor NSC23766 has off target effects on CXCR4. Cell Signal 2018; 42:88-96. [DOI: 10.1016/j.cellsig.2017.10.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/11/2017] [Accepted: 10/13/2017] [Indexed: 12/17/2022]
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61
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Cao X, Yan J. Identification of Associated Proteins by Immunoprecipitation and Mass Spectrometry Analysis. Methods Mol Biol 2017; 1407:131-9. [PMID: 27271899 DOI: 10.1007/978-1-4939-3480-5_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Protein-protein interactions play central roles in intercellular and intracellular signal transduction. Impairment of protein-protein interactions causes many diseases such as cancer, cardiomyopathies, diabetes, microbial infections, and genetic and neurodegenerative disorders. Immunoprecipitation is a technique in which a target protein of interest bound by an antibody is used to pull down the protein complex out of cell lysates, which can be identified by mass spectrometry. Here, we describe the protocol to immunoprecipitate and identify the components of the protein complexes of ElmoE in Dictyostelium discoideum cells.
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Affiliation(s)
- Xiumei Cao
- Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, South Chongqing Road No. 280, Shanghai, 200025, China
| | - Jianshe Yan
- Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, South Chongqing Road No. 280, Shanghai, 200025, China.
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62
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Zhang B, Feng L, Guo H, Li H, Wang Y, Zhang K, Yu X, Cheng S. Villi-specific Gene Expression Reveals Novel Prognostic Biomarkers in Multiple Human Cancers. J Cancer 2017; 8:2793-2801. [PMID: 28928868 PMCID: PMC5604211 DOI: 10.7150/jca.19787] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/07/2017] [Indexed: 11/26/2022] Open
Abstract
Despite many striking connections, the biological similarities between embryonic development and tumorigenesis have not been well explored. Development of the placental villi is a crucial process involving many cellular activities, including immunity, proliferation, and cell adhesion. In this study, we designed a strategy to identify the gene expression pattern of villi development and to explore the corresponding features in tumors. We discovered villi-specific genes that are highly expressed in the villus as opposed to the mature placenta and then measured the expression levels of these genes in tumors. We found large changes in the expression of villi-specific genes in multiple types of cancer. These villi-specific genes showed distinct expression patterns and were primarily involved in three biological processes: immune-related (5), proliferation-related (6), and focal adhesion-related (8); these genes were extracted from the corresponding enriched Gene Ontology (GO) terms. We observed that these genes were also dysregulated at the transcriptional level across several tumor types. Moreover, the expression of these three gene groups was associated with poor prognosis in a subset of tumors. Based on villi-specific gene expression, this correlation study indicated the existence of common gene expression patterns between embryonic development and tumorigenesis. Therefore, a systematic analysis of villi-specific gene aberrations in various tumors could serve as an indicator for identifying novel prognostic biomarkers.
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Affiliation(s)
- Botao Zhang
- State Key Laboratory of Molecular Oncology, Department of Etiology and Carcinogenesis, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China
| | - Lin Feng
- State Key Laboratory of Molecular Oncology, Department of Etiology and Carcinogenesis, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China
| | - Honglin Guo
- State Key Laboratory of Molecular Oncology, Department of Etiology and Carcinogenesis, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China
| | - Hongxia Li
- Department of Obstetrics and Gynecology, Beijing Shijitan Hospital, Capital Medical University, Beijing, 100038, China
| | - Yuanjing Wang
- Department of Obstetrics and Gynecology, Beijing Shijitan Hospital, Capital Medical University, Beijing, 100038, China
| | - Kaitai Zhang
- State Key Laboratory of Molecular Oncology, Department of Etiology and Carcinogenesis, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China
| | - Xuexin Yu
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin, 150081, China
| | - Shujun Cheng
- State Key Laboratory of Molecular Oncology, Department of Etiology and Carcinogenesis, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China
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63
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Xu X, Jin T. ELMO proteins transduce G protein-coupled receptor signal to control reorganization of actin cytoskeleton in chemotaxis of eukaryotic cells. Small GTPases 2017. [PMID: 28641070 PMCID: PMC6548286 DOI: 10.1080/21541248.2017.1318816] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Chemotaxis, which is chemoattractant-guided directional cell migration, plays major roles in recruitment of neutrophils, the metastasis of cancer cells, and the development of the model organism Dictyostelium discoideum. These cells share remarkable similarities in the signaling pathways by which they control chemotaxis. They all use a G protein-coupled receptor (GPCR)-mediated signal transduction pathway to sense the chemotactic gradient to guide cell migration. Diverse chemokines activate Rac through conserved GPCR signaling pathways. ELMO proteins are an evolutionarily conserved, essential component of the ELMO/Dock complex, which functions as a guanine nucleotide exchange factor (GEF) for small G protein Rac activation. The linkages between the GPCR-initiated gradient sensing compass and the Rac-mediated migrating machinery have long been missing. Here, we summarize recent findings on ELMO proteins that directly interact with G protein and transduce GPCR signaling to control the reorganization of actin-based cytoskeleton through regulating Rac activation during chemotaxis, first in D. discoideum and then in mammalian cancer cells. This represents an evolutionarily conserved signaling shortcut from GPCR to the actin cytoskeleton.
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Affiliation(s)
- Xuehua Xu
- a Chemotaxis Signal Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases , National Institutes of Health , Rockville , MD , USA
| | - Tian Jin
- a Chemotaxis Signal Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases , National Institutes of Health , Rockville , MD , USA
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64
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Fond AM, Ravichandran KS. Clearance of Dying Cells by Phagocytes: Mechanisms and Implications for Disease Pathogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 930:25-49. [PMID: 27558816 PMCID: PMC6721615 DOI: 10.1007/978-3-319-39406-0_2] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The efficient clearance of apoptotic cells is an evolutionarily conserved process crucial for homeostasis in multicellular organisms. The clearance involves a series of steps that ultimately facilitates the recognition of the apoptotic cell by the phagocytes and the subsequent uptake and processing of the corpse. These steps include the phagocyte sensing of "find-me" signals released by the apoptotic cell, recognizing "eat-me" signals displayed on the apoptotic cell surface, and then intracellular signaling within the phagocyte to mediate phagocytic cup formation around the corpse and corpse internalization, and the processing of the ingested contents. The engulfment of apoptotic cells by phagocytes not only eliminates debris from tissues but also produces an anti-inflammatory response that suppresses local tissue inflammation. Conversely, impaired corpse clearance can result in loss of immune tolerance and the development of various inflammation-associated disorders such as autoimmunity, atherosclerosis, and airway inflammation but can also affect cancer progression. Recent studies suggest that the clearance process can also influence antitumor immune responses. In this review, we will discuss how apoptotic cells interact with their engulfing phagocytes to generate important immune responses, and how modulation of such responses can influence pathology.
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Affiliation(s)
- Aaron M Fond
- Center for Cell Clearance, and the Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, 22908, USA
| | - Kodi S Ravichandran
- Center for Cell Clearance, and the Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, 22908, USA.
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Gámez-Pozo A, Trilla-Fuertes L, Prado-Vázquez G, Chiva C, López-Vacas R, Nanni P, Berges-Soria J, Grossmann J, Díaz-Almirón M, Ciruelos E, Sabidó E, Espinosa E, Fresno Vara JÁ. Prediction of adjuvant chemotherapy response in triple negative breast cancer with discovery and targeted proteomics. PLoS One 2017; 12:e0178296. [PMID: 28594844 PMCID: PMC5464546 DOI: 10.1371/journal.pone.0178296] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/10/2017] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Triple-negative breast cancer (TNBC) accounts for 15-20% of all breast cancers and usually requires the administration of adjuvant chemotherapy after surgery but even with this treatment many patients still suffer from a relapse. The main objective of this study was to identify proteomics-based biomarkers that predict the response to standard adjuvant chemotherapy, so that patients at are not going to benefit from it can be offered therapeutic alternatives. METHODS We analyzed the proteome of a retrospective series of formalin-fixed, paraffin-embedded TNBC tissue applying high-throughput label-free quantitative proteomics. We identified several protein signatures with predictive value, which were validated with quantitative targeted proteomics in an independent cohort of patients and further evaluated in publicly available transcriptomics data. RESULTS Using univariate Cox analysis, a panel of 18 proteins was significantly associated with distant metastasis-free survival of patients (p<0.01). A reduced 5-protein profile with prognostic value was identified and its prediction performance was assessed in an independent targeted proteomics experiment and a publicly available transcriptomics dataset. Predictor P5 including peptides from proteins RAC2, RAB6A, BIEA and IPYR was the best performance protein combination in predicting relapse after adjuvant chemotherapy in TNBC patients. CONCLUSIONS This study identified a protein combination signature that complements histopathological prognostic factors in TNBC treated with adjuvant chemotherapy. The protein signature can be used in paraffin-embedded samples, and after a prospective validation in independent series, it could be used as predictive clinical test in order to recommend participation in clinical trials or a more exhaustive follow-up.
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Affiliation(s)
- Angelo Gámez-Pozo
- Molecular Oncology & Pathology Lab, Instituto de Genética Médica y Molecular-INGEMM, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
- Biomedica Molecular Medicine SL, Madrid, Spain
| | | | - Guillermo Prado-Vázquez
- Molecular Oncology & Pathology Lab, Instituto de Genética Médica y Molecular-INGEMM, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
| | - Cristina Chiva
- Proteomics Unit, Center of Genomics Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Proteomics Unit, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Rocío López-Vacas
- Molecular Oncology & Pathology Lab, Instituto de Genética Médica y Molecular-INGEMM, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
| | - Paolo Nanni
- Functional Genomics Centre Zurich, University of Zurich/ETH Zurich, Zurich, Switzerland
| | - Julia Berges-Soria
- Molecular Oncology & Pathology Lab, Instituto de Genética Médica y Molecular-INGEMM, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
| | - Jonas Grossmann
- Functional Genomics Centre Zurich, University of Zurich/ETH Zurich, Zurich, Switzerland
| | | | - Eva Ciruelos
- Medical Oncology Service, Instituto de Investigación Hospital Universitario Doce de Octubre-i+12, Madrid, Spain
| | - Eduard Sabidó
- Proteomics Unit, Center of Genomics Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Proteomics Unit, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Enrique Espinosa
- Medical Oncology Service, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
- CIBERONC. Instituto de Salud Carlos III, Madrid, Spain
| | - Juan Ángel Fresno Vara
- Molecular Oncology & Pathology Lab, Instituto de Genética Médica y Molecular-INGEMM, Hospital Universitario La Paz-IdiPAZ, Madrid, Spain
- Biomedica Molecular Medicine SL, Madrid, Spain
- CIBERONC. Instituto de Salud Carlos III, Madrid, Spain
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66
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Winge MCG, Marinkovich MP. Epidermal activation of the small GTPase Rac1 in psoriasis pathogenesis. Small GTPases 2017; 10:163-168. [PMID: 28055293 DOI: 10.1080/21541248.2016.1273861] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The small GTPase Ras-related C3 botulinum toxin substrate 1 (RAC1) plays a central role in skin homeostasis, including barrier function, wound healing and inflammatory responses. Psoriasis is a common skin disease characterized by deregulation of these functions, and affected skin exhibit keratinocyte hyperproliferation, inflammation and immune cell infiltration. Although psoriasis is often triggered by environmental stimulus, there is a strong genetic association with genes expressed in both immune cells and keratinocytes, of which several are linked to Rac1 signaling. Rac1 is highly active in human psoriatic lesional skin and keratinocytes, and keratinocyte-specific overexpression of an activated mutant of Rac1, Rac1V12, in a transgenic mouse model closely mimics the presentation of human psoriasis. Both Rac1 activation in keratinocytes and immune derived stimulus are required to drive psoriasiform signaling in transgenic mouse and human xenograft models of psoriasis. Therefore, understanding how increased Rac1 activation in psoriatic epidermis is regulated is central to understanding how the abnormal crosstalk between keratinocytes and immune cells is maintained.
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Affiliation(s)
- Mårten C G Winge
- a Program in Epithelial Biology , Stanford University School of Medicine , Stanford , CA , USA
| | - M Peter Marinkovich
- a Program in Epithelial Biology , Stanford University School of Medicine , Stanford , CA , USA.,b Dermatology Service , Veterans Affairs Medical Center , Palo Alto , CA , USA
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67
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McCauley HA, Chevrier V, Birnbaum D, Guasch G. De-repression of the RAC activator ELMO1 in cancer stem cells drives progression of TGFβ-deficient squamous cell carcinoma from transition zones. eLife 2017; 6:e22914. [PMID: 28219480 PMCID: PMC5319840 DOI: 10.7554/elife.22914] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 01/27/2017] [Indexed: 01/18/2023] Open
Abstract
Squamous cell carcinomas occurring at transition zones are highly malignant tumors with poor prognosis. The identity of the cell population and the signaling pathways involved in the progression of transition zone squamous cell carcinoma are poorly understood, hence representing limited options for targeted therapies. Here, we identify a highly tumorigenic cancer stem cell population in a mouse model of transitional epithelial carcinoma and uncover a novel mechanism by which loss of TGFβ receptor II (Tgfbr2) mediates invasion and metastasis through de-repression of ELMO1, a RAC-activating guanine exchange factor, specifically in cancer stem cells of transition zone tumors. We identify ELMO1 as a novel target of TGFβ signaling and show that restoration of Tgfbr2 results in a complete block of ELMO1 in vivo. Knocking down Elmo1 impairs metastasis of carcinoma cells to the lung, thereby providing insights into the mechanisms of progression of Tgfbr2-deficient invasive transition zone squamous cell carcinoma.
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Affiliation(s)
- Heather A McCauley
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, United States
| | - Véronique Chevrier
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068, F-13009, CNRS, UMR7258, F-13009, Institut Paoli-Calmettes, F-13009, Aix-Marseille University, UM 105, F-13284, Marseille, France
| | - Daniel Birnbaum
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068, F-13009, CNRS, UMR7258, F-13009, Institut Paoli-Calmettes, F-13009, Aix-Marseille University, UM 105, F-13284, Marseille, France
| | - Géraldine Guasch
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, United States
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068, F-13009, CNRS, UMR7258, F-13009, Institut Paoli-Calmettes, F-13009, Aix-Marseille University, UM 105, F-13284, Marseille, France
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68
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Knockdown of ELMO3 Suppresses Growth, Invasion and Metastasis of Colorectal Cancer. Int J Mol Sci 2016; 17:ijms17122119. [PMID: 27999268 PMCID: PMC5187919 DOI: 10.3390/ijms17122119] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/05/2016] [Accepted: 12/12/2016] [Indexed: 01/08/2023] Open
Abstract
The engulfment and cell motility (ELMOs) family of proteins plays a crucial role in tumor cell migration and invasion. However, the function of ELMO3 is poorly defined. To elucidate its role in the development and progression of colorectal cancer (CRC), we examined the expression of ELMO3 in 45 cases of paired CRC tumor tissues and adjacent normal tissues. Furthermore, we assessed the effect of the knockdown of ELMO3 on cell proliferation, cell cycle, migration, invasion and F-actin polymerization in HCT116 cells. The result shows that the expression of ELMO3 in CRC tissues was significantly increased in comparison to the adjacent normal colorectal tissues. Moreover, this overexpression was associated with tumor size (p = 0.007), tumor differentiation (p = 0.001), depth of invasion (p = 0.009), lymph node metastasis (p = 0.003), distant metastasis (p = 0.013) and tumor, node, metastasis (TNM)-based classification (p = 0.000). In in vitro experiments, the silencing of ELMO3 inhibited cell proliferation, invasion, metastasis, and F-actin polymerization, and induced Gap 1 (G1) phase cell cycle arrest. Our study demonstrates that ELMO3 is involved in the processes of growth, invasion and metastasis of CRC, and could be used a potential molecular diagnostic tool or therapy target of CRC.
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69
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Worsham MJ, Chen KM, Datta I, Stephen JK, Chitale D, Gothard A, Divine G. The biological significance of methylome differences in human papilloma virus associated head and neck cancer. Oncol Lett 2016; 12:4949-4956. [PMID: 28101231 PMCID: PMC5228097 DOI: 10.3892/ol.2016.5303] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 08/26/2016] [Indexed: 01/02/2023] Open
Abstract
In recent years, studies have suggested that promoter methylation in human papilloma virus (HPV) positive head and neck squamous cell carcinoma (HNSCC) has a mechanistic role and has the potential to improve patient survival. The present study aimed to replicate key molecular findings from previous analyses of the methylomes of HPV positive and HPV negative HNSCC in an independent cohort, to assess the reliability of differentially methylated markers in HPV-associated tumors. HPV was measured using real-time quantitative PCR and the biological significance of methylation differences was assessed by Ingenuity Pathway Analysis (IPA). Using an identical experimental design of a 450K methylation platform, 7 of the 11 genes were detected to be significantly differentially methylated and all 11 genes were either hypo- or hypermethylated, which was in agreement with the results of a previous study. IPA's enriched networks analysis identified one network with msh homeobox 2 (MSX2) as a central node. Locally dense interactions between genes in networks tend to reflect significant biology; therefore MSX2 was selected as an important gene. Sequestration in the top four canonical pathways was noted for 5-hydroxytryptamine receptor 1E (serotonin signaling), collapsin response mediator protein 1 (semaphorin signaling) and paired like homeodomain 2 (bone morphogenic protein and transforming growth factor-β signaling). Placement of 9 of the 11 genes in highly ranked pathways and bionetworks identified key biological processes to further emphasize differences between HNSCC HPV positive and negative pathogenesis.
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Affiliation(s)
- Maria J Worsham
- Department of Otolaryngology/Head and Neck Research, Henry Ford Hospital, Detroit, MI 48202, USA
| | - Kang Mei Chen
- Department of Otolaryngology/Head and Neck Research, Henry Ford Hospital, Detroit, MI 48202, USA
| | - Indrani Datta
- Department of Public Health Sciences, Henry Ford Hospital, Detroit, MI 48202, USA
| | - Josena K Stephen
- Department of Otolaryngology/Head and Neck Research, Henry Ford Hospital, Detroit, MI 48202, USA
| | - Dhananjay Chitale
- Department of Pathology, Henry Ford Hospital, Detroit, MI 48202, USA
| | | | - George Divine
- Department of Public Health Sciences, Henry Ford Hospital, Detroit, MI 48202, USA
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70
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Liu Y, Lacal J, Firtel RA, Kortholt A. Connecting G protein signaling to chemoattractant-mediated cell polarity and cytoskeletal reorganization. Small GTPases 2016; 9:360-364. [PMID: 27715492 PMCID: PMC5997169 DOI: 10.1080/21541248.2016.1235390] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The directional movement toward extracellular chemical gradients, a process called chemotaxis, is an important property of cells. Central to eukaryotic chemotaxis is the molecular mechanism by which chemoattractant-mediated activation of G-protein coupled receptors (GPCRs) induces symmetry breaking in the activated downstream signaling pathways. Studies with mainly Dictyostelium and mammalian neutrophils as experimental systems have shown that chemotaxis is mediated by a complex network of signaling pathways. Recently, several labs have used extensive and efficient proteomic approaches to further unravel this dynamic signaling network. Together these studies showed the critical role of the interplay between heterotrimeric G-protein subunits and monomeric G proteins in regulating cytoskeletal rearrangements during chemotaxis. Here we highlight how these proteomic studies have provided greater insight into the mechanisms by which the heterotrimeric G protein cycle is regulated, how heterotrimeric G proteins-induced symmetry breaking is mediated through small G protein signaling, and how symmetry breaking in G protein signaling subsequently induces cytoskeleton rearrangements and cell migration.
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Affiliation(s)
- Youtao Liu
- a Department of Cell Biochemistry , University of Groningen , Groningen , The Netherlands
| | - Jesus Lacal
- b Section of Cell and Developmental Biology, Division of Biological Sciences, University of California , San Diego, La Jolla , CA , USA
| | - Richard A Firtel
- b Section of Cell and Developmental Biology, Division of Biological Sciences, University of California , San Diego, La Jolla , CA , USA
| | - Arjan Kortholt
- a Department of Cell Biochemistry , University of Groningen , Groningen , The Netherlands
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71
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Noubissi FK, Ogle BM. Cancer Cell Fusion: Mechanisms Slowly Unravel. Int J Mol Sci 2016; 17:ijms17091587. [PMID: 27657058 PMCID: PMC5037852 DOI: 10.3390/ijms17091587] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/26/2016] [Accepted: 09/12/2016] [Indexed: 01/15/2023] Open
Abstract
Although molecular mechanisms and signaling pathways driving invasion and metastasis have been studied for many years, the origin of the population of metastatic cells within the primary tumor is still not well understood. About a century ago, Aichel proposed that cancer cell fusion was a mechanism of cancer metastasis. This hypothesis gained some support over the years, and recently became the focus of many studies that revealed increasing evidence pointing to the possibility that cancer cell fusion probably gives rise to the metastatic phenotype by generating widespread genetic and epigenetic diversity, leading to the emergence of critical populations needed to evolve resistance to the treatment and development of metastasis. In this review, we will discuss the clinical relevance of cancer cell fusion, describe emerging mechanisms of cancer cell fusion, address why inhibiting cancer cell fusion could represent a critical line of attack to limit drug resistance and to prevent metastasis, and suggest one new modality for doing so.
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Affiliation(s)
| | - Brenda M Ogle
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
- Stem Cell Institute, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
- Masonic Cancer Center, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
- Lillehei Heart Institute, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
- Institute for Engineering and Medicine, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
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72
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Vázquez-Prado J, Bracho-Valdés I, Cervantes-Villagrana RD, Reyes-Cruz G. Gβγ Pathways in Cell Polarity and Migration Linked to Oncogenic GPCR Signaling: Potential Relevance in Tumor Microenvironment. Mol Pharmacol 2016; 90:573-586. [DOI: 10.1124/mol.116.105338] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 09/14/2016] [Indexed: 12/16/2022] Open
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73
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Jing X, Wu H, Ji X, Wu H, Shi M, Zhao R. Cortactin promotes cell migration and invasion through upregulation of the dedicator of cytokinesis 1 expression in human colorectal cancer. Oncol Rep 2016; 36:1946-1952. [PMID: 27633051 DOI: 10.3892/or.2016.5058] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 08/16/2016] [Indexed: 11/06/2022] Open
Abstract
Cortactin (CTTN), a major substrate of the Src tyrosine kinase, has been implicated in cell proliferation, motility and invasion in various types of cancer. However, the molecular mechanisms of CTTN-driven malignant behavior remain unclear. In the current study, we determined the expression of CTTN in colorectal cancer and investigated its underlying mechanism in the metastasis of colorectal cancer. We confirmed increased CTTN expression in lymph node-positive CRC specimens and highly invasive CRC cell lines. Further study has shown that overexpression of CTTN promoted CRC cell migration and invasion, whereas CTTN silencing inhibited CRC cell migratory and invasive capacities in vitro. Mechanistically, CTTN increases expression of dedicator of cytokinesis 1 (DOCK1) and gene silencing of DOCK1 partially abolishes the migration and invasion capacity by CTTN. Our findings indicate that CTTN promotes metastasis of CRC cells by increasing DOCK1 expression and this could offer a promising therapeutic target for colorectal cancer treatment.
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Affiliation(s)
- Xiaoqian Jing
- Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Huo Wu
- Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Xiaopin Ji
- Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Haoxuan Wu
- Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Minmin Shi
- Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Ren Zhao
- Department of Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
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74
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Phosphoproteomic profiling of mouse primary HSPCs reveals new regulators of HSPC mobilization. Blood 2016; 128:1465-74. [PMID: 27365422 DOI: 10.1182/blood-2016-05-711424] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 06/28/2016] [Indexed: 12/14/2022] Open
Abstract
Protein phosphorylation is a central mechanism of signal transduction that both positively and negatively regulates protein function. Large-scale studies of the dynamic phosphorylation states of cell signaling systems have been applied extensively in cell lines and whole tissues to reveal critical regulatory networks, and candidate-based evaluations of phosphorylation in rare cell populations have also been informative. However, application of comprehensive profiling technologies to adult stem cell and progenitor populations has been challenging, due in large part to the scarcity of such cells in adult tissues. Here, we combine multicolor flow cytometry with highly efficient 3-dimensional high performance liquid chromatography/mass spectrometry to enable quantitative phosphoproteomic analysis from 200 000 highly purified primary mouse hematopoietic stem and progenitor cells (HSPCs). Using this platform, we identify ARHGAP25 as a novel regulator of HSPC mobilization and demonstrate that ARHGAP25 phosphorylation at serine 363 is an important modulator of its function. Our approach provides a robust platform for large-scale phosphoproteomic analyses performed with limited numbers of rare progenitor cells. Data from our study comprises a new resource for understanding the molecular signaling networks that underlie hematopoietic stem cell mobilization.
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75
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A Gα-Stimulated RapGEF Is a Receptor-Proximal Regulator of Dictyostelium Chemotaxis. Dev Cell 2016; 37:458-72. [PMID: 27237792 DOI: 10.1016/j.devcel.2016.05.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 02/15/2016] [Accepted: 04/29/2016] [Indexed: 12/19/2022]
Abstract
Chemotaxis, or directional movement toward extracellular chemical gradients, is an important property of cells that is mediated through G-protein-coupled receptors (GPCRs). Although many chemotaxis pathways downstream of Gβγ have been identified, few Gα effectors are known. Gα effectors are of particular importance because they allow the cell to distinguish signals downstream of distinct chemoattractant GPCRs. Here we identify GflB, a Gα2 binding partner that directly couples the Dictyostelium cyclic AMP GPCR to Rap1. GflB localizes to the leading edge and functions as a Gα-stimulated, Rap1-specific guanine nucleotide exchange factor required to balance Ras and Rap signaling. The kinetics of GflB translocation are fine-tuned by GSK-3 phosphorylation. Cells lacking GflB display impaired Rap1/Ras signaling and actin and myosin dynamics, resulting in defective chemotaxis. Our observations demonstrate that GflB is an essential upstream regulator of chemoattractant-mediated cell polarity and cytoskeletal reorganization functioning to directly link Gα activation to monomeric G-protein signaling.
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76
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Sun Y, Côté JF, Du K. Elmo2 Is a Regulator of Insulin-dependent Glut4 Membrane Translocation. J Biol Chem 2016; 291:16150-61. [PMID: 27226625 DOI: 10.1074/jbc.m116.731521] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Indexed: 11/06/2022] Open
Abstract
Elmo2, a member of the Elmo protein family, has been implicated in the regulation of Rac1 and Akt activation. Recently, we found that Elmo2 specifically interacts with ClipR-59. Because Akt and Rac1 have been implicated in insulin dependent Glut4 membrane translocation, we hypothesize here that Elmo2 may play a role in insulin-dependent Glut4 membrane translocation. Accordingly, we found that overexpression of Elmo2 enhanced, whereas its knockdown suppressed, insulin-dependent Glut4 membrane translocation in both 3T3-L1 adipocytes and L6 skeletal muscle cells. We also examined whether Elmo2 contributes to the insulin-mediated activation of Rac1 and Akt. We found that Elmo2 is required for insulin-induced Rac1 GTP loading, but not AKT activation, in L6 cells induced by insulin. Instead, Elmo2 is required to promote the insulin-induced membrane association of Akt. Together, our studies demonstrate that Elmo2 is a new regulator of insulin-dependent Glut4 membrane translocation through modulating Rac1 activity and Akt membrane compartmentalization.
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Affiliation(s)
- Yingmin Sun
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111 and
| | - Jean-François Côté
- the Institut de Recherches Cliniques de Montréal, Université de Montréal, Montréal, Québec H2W 1R7, Canada
| | - Keyong Du
- From the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111 and
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77
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Wang Y, Xu X, Pan M, Jin T. ELMO1 Directly Interacts with Gβγ Subunit to Transduce GPCR Signaling to Rac1 Activation in Chemotaxis. J Cancer 2016; 7:973-83. [PMID: 27313788 PMCID: PMC4910590 DOI: 10.7150/jca.15118] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/14/2016] [Indexed: 01/13/2023] Open
Abstract
Diverse chemokines bind to G protein-coupled receptors (GPCRs) to activate the small GTPase Rac to regulate F-actin dynamics during chemotaxis. ELMO and Dock proteins form complexes that function as guanine nucleotide exchange factors (GEFs) for Rac activation. However, the linkage between GPCR activation and the ELMO/Dock-mediated Rac activation is not fully understood. In the present study, we show that chemoattractants induce dynamic membrane translocation of ELMO1 in mammalian cells. ELMO1 plays an important role in GPCR-mediated chemotaxis. We also reveal that ELMO1 and Dock1 form a stable complex. Importantly, activation of chemokine GPCR promotes the interaction between ELMO1 and Gβγ. The ELMO1-Gβγ interaction is through the N-terminus of ELMO1 protein and is important for the membrane translocation of ELMO1. ELMO1 is required for Rac1 activation upon chemoattractant stimulation. Our results suggest that chemokine GPCR-mediated interaction between Gβγ and ELMO1/Dock1 complex might serve as an evolutionarily conserved mechanism for Rac activation to regulate actin cytoskeleton for chemotaxis of human cells.
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Affiliation(s)
- Youhong Wang
- Chemotaxis Signaling Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Rockville, MD 20852, USA
| | - Xuehua Xu
- Chemotaxis Signaling Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Rockville, MD 20852, USA
| | - Miao Pan
- Chemotaxis Signaling Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Rockville, MD 20852, USA
| | - Tian Jin
- Chemotaxis Signaling Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Rockville, MD 20852, USA
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78
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Zhang B, Li H, Yin C, Sun X, Zheng S, Zhang C, Shi L, Liu Y, Lu S. Dock1 promotes the mesenchymal transition of glioma and is modulated by MiR‐31. Neuropathol Appl Neurobiol 2016; 43:419-432. [PMID: 26946516 DOI: 10.1111/nan.12321] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 02/25/2016] [Accepted: 03/04/2016] [Indexed: 12/26/2022]
Affiliation(s)
- Baogang Zhang
- Department of Pathology Weifang Medical University Weifang China
| | - Hongli Li
- Medicine Research Center Weifang Medical University Weifang China
| | - Chonggao Yin
- College of Nursing Weifang Medical University Weifang China
| | - Xuemei Sun
- Department of Pathology Weifang Medical University Weifang China
| | - Shuxian Zheng
- Department of Pathology Weifang Medical University Weifang China
| | - Changjie Zhang
- Department of Pathology Weifang Medical University Weifang China
| | - Lihong Shi
- Department of Pharmacology Weifang Medical University Weifang China
| | - Yuqing Liu
- Department of Pathology Weifang Medical University Weifang China
| | - Shijun Lu
- Department of Pathology Weifang Medical University Weifang China
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Kamp ME, Liu Y, Kortholt A. Function and Regulation of Heterotrimeric G Proteins during Chemotaxis. Int J Mol Sci 2016; 17:ijms17010090. [PMID: 26784171 PMCID: PMC4730333 DOI: 10.3390/ijms17010090] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 12/22/2015] [Accepted: 12/31/2015] [Indexed: 01/10/2023] Open
Abstract
Chemotaxis, or directional movement towards an extracellular gradient of chemicals, is necessary for processes as diverse as finding nutrients, the immune response, metastasis and wound healing. Activation of G-protein coupled receptors (GPCRs) is at the very base of the chemotactic signaling pathway. Chemotaxis starts with binding of the chemoattractant to GPCRs at the cell-surface, which finally leads to major changes in the cytoskeleton and directional cell movement towards the chemoattractant. Many chemotaxis pathways that are directly regulated by Gβγ have been identified and studied extensively; however, whether Gα is just a handle that regulates the release of Gβγ or whether Gα has its own set of distinct chemotactic effectors, is only beginning to be understood. In this review, we will discuss the different levels of regulation in GPCR signaling and the downstream pathways that are essential for proper chemotaxis.
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Affiliation(s)
- Marjon E Kamp
- Department of Cell Biochemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Youtao Liu
- Department of Cell Biochemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Arjan Kortholt
- Department of Cell Biochemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
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80
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Shi Q, Liu X, Zeng T, Wang W, Chen L. Detecting disease genes of non-small lung cancer based on consistently differential interactions. Cancer Metastasis Rev 2015; 34:195-208. [DOI: 10.1007/s10555-015-9561-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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81
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LASP-1: a nuclear hub for the UHRF1-DNMT1-G9a-Snail1 complex. Oncogene 2015; 35:1122-33. [PMID: 25982273 PMCID: PMC4651668 DOI: 10.1038/onc.2015.166] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 04/09/2015] [Accepted: 04/12/2015] [Indexed: 12/30/2022]
Abstract
Nuclear LASP-1 has a direct correlation with overall survival of breast cancer patients. In this study, immunohistochemical analysis of a human breast TMA showed that LASP-1 is absent in normal human breast epithelium but the expression increases with malignancy and is highly nuclear in aggressive breast cancer. We investigated whether the chemokines and growth factors present in the tumor microenvironment could trigger nuclear translocation of LASP-1.Treatment of human breast cancer cells with CXCL12, EGF and Heregulin and HMEC-CXCR2 cells with CXCL8 facilitated nuclear shuttling of LASP-1. Data from the biochemical analysis of the nuclear and cytosolic fractions further confirmed the nuclear translocation of LASP-1 upon chemokine and growth factor treatment. CXCL12-dependent nuclear import of LASP-1 could be blocked by CXCR4 antagonist, AMD-3100. Knock down of LASP-1 resulted in alterations in gene expression leading to an increased level of cell junction and extracellular matrix proteins and an altered cytokine secretory profile. Three dimensional cultures of human breast cancer cells on Matrigel revealed an altered colony growth, morphology and arborization pattern in LASP-1 knock down cells. Functional analysis of the LASP-1 knock down cells revealed increased adhesion to collagen IV and decreased invasion through the Matrigel. Proteomics analysis of immunoprecipitates of LASP-1 and subsequent validation approaches revealed that LASP-1associated with the epigenetic machinery especially UHRF1, DNMT1, G9a and the transcription factor Snail1. Interestingly, LASP-1 associated with UHRF1, G9a, Snail1 and di- and tri-methylated histoneH3 in a CXCL12-dependent manner based on immunoprecipitation and proximity ligation assays. LASP-1 also directly bound to Snail1 which may stabilize Snail1. Thus, nuclear LASP-1 appears to functionally serve as a hub for the epigenetic machinery.
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82
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Wu J, Pipathsouk A, Keizer-Gunnink A, Fusetti F, Alkema W, Liu S, Altschuler S, Wu L, Kortholt A, Weiner OD. Homer3 regulates the establishment of neutrophil polarity. Mol Biol Cell 2015; 26:1629-39. [PMID: 25739453 PMCID: PMC4436775 DOI: 10.1091/mbc.e14-07-1197] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 01/10/2023] Open
Abstract
Most chemoattractants rely on activation of the heterotrimeric G-protein Gαi to regulate directional cell migration, but few links from Gαi to chemotactic effectors are known. Through affinity chromatography using primary neutrophil lysate, we identify Homer3 as a novel Gαi2-binding protein. RNA interference-mediated knockdown of Homer3 in neutrophil-like HL-60 cells impairs chemotaxis and the establishment of polarity of phosphatidylinositol 3,4,5-triphosphate (PIP3) and the actin cytoskeleton, as well as the persistence of the WAVE2 complex. Most previously characterized proteins that are required for cell polarity are needed for actin assembly or activation of core chemotactic effectors such as the Rac GTPase. In contrast, Homer3-knockdown cells show normal magnitude and kinetics of chemoattractant-induced activation of phosphoinositide 3-kinase and Rac effectors. Chemoattractant-stimulated Homer3-knockdown cells also exhibit a normal initial magnitude of actin polymerization but fail to polarize actin assembly and intracellular PIP3 and are defective in the initiation of cell polarity and motility. Our data suggest that Homer3 acts as a scaffold that spatially organizes actin assembly to support neutrophil polarity and motility downstream of GPCR activation.
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Affiliation(s)
- Julie Wu
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158
| | - Anne Pipathsouk
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158
| | - A Keizer-Gunnink
- Department of Cell Biochemistry, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, 9700 AB Groningen, Netherlands
| | - F Fusetti
- Department of Biochemistry and Netherlands Proteomics Centre, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, 9700 AB Groningen, Netherlands
| | - W Alkema
- NIZO Food Research, 6718 ZB Ede, Netherlands Centre for Molecular and Biomolecular Informatics, Radboud University Medical Center, Nijmegen, 6525 GA Nijmegen, Netherlands
| | - Shanshan Liu
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Steven Altschuler
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Lani Wu
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Arjan Kortholt
- Department of Cell Biochemistry, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, 9700 AB Groningen, Netherlands
| | - Orion D Weiner
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158
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83
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Whitaker JW, Boyle DL, Bartok B, Ball ST, Gay S, Wang W, Firestein GS. Integrative omics analysis of rheumatoid arthritis identifies non-obvious therapeutic targets. PLoS One 2015; 10:e0124254. [PMID: 25901943 PMCID: PMC4406750 DOI: 10.1371/journal.pone.0124254] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 03/12/2015] [Indexed: 11/19/2022] Open
Abstract
Identifying novel therapeutic targets for the treatment of disease is challenging. To this end, we developed a genome-wide approach of candidate gene prioritization. We independently collocated sets of genes that were implicated in rheumatoid arthritis (RA) pathogenicity through three genome-wide assays: (i) genome-wide association studies (GWAS), (ii) differentially expression in RA fibroblast-like synoviocytes (FLS), and (iii) differentially methylation in RA FLS. Integrated analysis of these complementary data sets identified a significant enrichment of multi-evidence genes (MEGs) within pathways relating to RA pathogenicity. One MEG is Engulfment and Cell Motility Protein-1 (ELMO1), a gene not previously considered as a therapeutic target in RA FLS. We demonstrated in RA FLS that ELMO1 is: (i) expressed, (ii) promotes cell migration and invasion, and (iii) regulates Rac1 activity. Thus, we created links between ELMO1 and RA pathogenicity, which in turn validates ELMO1 as a potential RA therapeutic target. This study illustrated the power of MEG-based approaches for therapeutic target identification.
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Affiliation(s)
- John W. Whitaker
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, United States of America
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
| | - David L. Boyle
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, California, United States of America
| | - Beatrix Bartok
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, California, United States of America
| | - Scott T. Ball
- Department of Orthopaedics, University of California San Diego School of Medicine, La Jolla, California, United States of America
| | - Steffen Gay
- Department of Rheumatology, University Hospital Zürich, CH-8091, Zurich, Switzerland
| | - Wei Wang
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, United States of America
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (WW); (GSF)
| | - Gary S. Firestein
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (WW); (GSF)
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84
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Sun Y, Ren W, Côté JF, Hinds PW, Hu X, Du K. ClipR-59 interacts with Elmo2 and modulates myoblast fusion. J Biol Chem 2015; 290:6130-40. [PMID: 25572395 PMCID: PMC4358253 DOI: 10.1074/jbc.m114.616680] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 01/06/2015] [Indexed: 11/06/2022] Open
Abstract
Recent studies using ClipR-59 knock-out mice implicated this protein in the regulation of muscle function. In this report, we have examined the role of ClipR-59 in muscle differentiation and found that ClipR-59 knockdown in C2C12 cells suppressed myoblast fusion. To elucidate the molecular mechanism whereby ClipR-59 regulates myoblast fusion, we carried out a yeast two-hybrid screen using ClipR-59 as the bait and identified Elmo2, a member of the Engulfment and cell motility protein family, as a novel ClipR-59-associated protein. We showed that the interaction between ClipR-59 and Elmo2 was mediated by the atypical PH domain of Elmo2 and the Glu-Pro-rich domain of ClipR-59 and regulated by Rho-GTPase. We have examined the impact of ClipR-59 on Elmo2 downstream signaling and found that interaction of ClipR-59 with Elmo2 enhanced Rac1 activation. Collectively, our studies demonstrate that formation of an Elmo2·ClipR-59 complex plays an important role in myoblast fusion.
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Affiliation(s)
- Yingmin Sun
- From the State Key Laboratory for Agro-biotechnology, College of Biological Science, China Agricultural University, 10083 Beijing, China, the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111, and
| | - Wenying Ren
- the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111, and
| | - Jean-François Côté
- the Institut de Recherches Cliniques de Montréal, Montréal, Université de Montréal, Québec H2W 1R7, Canada
| | - Philip W Hinds
- the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111, and
| | - Xiaoxiang Hu
- From the State Key Laboratory for Agro-biotechnology, College of Biological Science, China Agricultural University, 10083 Beijing, China
| | - Keyong Du
- the Molecular Oncology Research Institute, Tufts Medical Center, Boston, Massachusetts 02111, and
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85
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Axl phosphorylates Elmo scaffold proteins to promote Rac activation and cell invasion. Mol Cell Biol 2015; 35:76-87. [PMID: 25332238 PMCID: PMC4295393 DOI: 10.1128/mcb.00764-14] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The receptor tyrosine kinase Axl contributes to cell migration and invasion. Expression of Axl correlates with metastatic progression in cancer patients, yet the specific signaling events promoting invasion downstream of Axl are poorly defined. Herein, we report Elmo scaffolds to be direct substrates and binding partners of Axl. Elmo proteins are established to interact with Dock family guanine nucleotide exchange factors to control Rac-mediated cytoskeletal dynamics. Proteomics and mutagenesis studies reveal that Axl phosphorylates Elmo1/2 on a conserved carboxyl-terminal tyrosine residue. Upon Gas6-dependent activation of Axl, endogenous Elmo2 becomes phosphorylated on Tyr-713 and enters into a physical complex with Axl in breast cancer cells. Interfering with Elmo2 expression prevented Gas6-induced Rac1 activation in breast cancer cells. Similarly to blocking of Axl, Elmo2 knockdown or pharmacological inhibition of Dock1 abolishes breast cancer cell invasion. Interestingly, Axl or Elmo2 knockdown diminishes breast cancer cell proliferation. Rescue of Elmo2 knockdown cells with the wild-type protein but not with Elmo2 harboring Tyr-713-Phe mutations restores cell invasion and cell proliferation. These results define a new mechanism by which Axl promotes cell proliferation and invasion and identifies inhibition of the Elmo-Dock pathway as a potential therapeutic target to stop Axl-induced metastases.
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86
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Lu TL, Han CK, Chang YS, Lu TJ, Huang HC, Bao BY, Wu HY, Huang CH, Li CY, Wu TS. Denbinobin, a Phenanthrene from Dendrobium nobile, Impairs Prostate Cancer Migration by Inhibiting Rac1 Activity. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2014; 42:1539-54. [DOI: 10.1142/s0192415x14500967] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Prostate cancer is the most prevalent type of cancer in the United States. The most common site of prostate cancer metastasis is bone. CXCL12 is preferentially expressed in bone and is targeted by prostate cancer cells, which over-express the receptor for CXCL12, CXCR4. In response to CXCL12 stimulation, Rac1, a GTPase, along with its effectors, regulates actin polymerization to form lamellipodia, which is a critical event for cell migration. Cortactin, an actin-binding protein, is recruited to the lamellipodia and is phosphorylated at tyrosine residues. The phosphorylated cortactin is also involved in cell migration. The inhibition of Rac1 activity using a dominant negative Rac1 impairs lamellipodial protrusion as well as cortactin translocation and cortactin phosphorylation. Denbinobin, a substance extracted from Dendrobium nobile, has anticancer effects in many cancer cell lines. Whether denbinobin can inhibit prostate cancer cell migration is not clear. Here, we report that denbinobin inhibited Rac1 activity. The inhibition of Rac1 activity prevented lamellipodial formation. Cortactin phosphorylation and translocation to the lamellipodia were also impaired, and PC3 cells were unable to migrate. These results indicate that denbinobin prevents CXCL12-induced PC3 cell migration by inhibiting Rac1 activity.
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Affiliation(s)
- Te-Ling Lu
- School of Pharmacy, China Medical University, Taichung, Taiwan, ROC
- Tsuzuki Institute for Traditional Medicine, China Medical University, Taichung, Taiwan, ROC
| | - Chien-Kuo Han
- Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Yuan-Shiun Chang
- Department of Chinese Pharmaceutical Science and Chinese Medicine Resources, China Medical University, Taichung, Taiwan, ROC
| | - Te-Jung Lu
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, Tainan, Taiwan
| | - Hui-Chi Huang
- Department of Chinese Pharmaceutical Science and Chinese Medicine Resources, China Medical University, Taichung, Taiwan, ROC
| | - Bo-Ying Bao
- School of Pharmacy, China Medical University, Taichung, Taiwan, ROC
| | - Hsing-Yu Wu
- School of Pharmacy, China Medical University, Taichung, Taiwan, ROC
| | - Chieh-Hung Huang
- Department of Chemical Biology, National Pingtung University of Education, Pingtung, Taiwan
| | - Chia-Yen Li
- Department of Chemical Biology, National Pingtung University of Education, Pingtung, Taiwan
| | - Tian-Shung Wu
- School of Pharmacy, National Cheng Kung University, Tainan, Taiwan, ROC
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87
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Dirat B, Ader I, Golzio M, Massa F, Mettouchi A, Laurent K, Larbret F, Malavaud B, Cormont M, Lemichez E, Cuvillier O, Tanti JF, Bost F. Inhibition of the GTPase Rac1 mediates the antimigratory effects of metformin in prostate cancer cells. Mol Cancer Ther 2014; 14:586-96. [PMID: 25527635 DOI: 10.1158/1535-7163.mct-14-0102] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cell migration is a critical step in the progression of prostate cancer to the metastatic state, the lethal form of the disease. The antidiabetic drug metformin has been shown to display antitumoral properties in prostate cancer cell and animal models; however, its role in the formation of metastases remains poorly documented. Here, we show that metformin reduces the formation of metastases to fewer solid organs in an orthotopic metastatic prostate cancer cell model established in nude mice. As predicted, metformin hampers cell motility in PC3 and DU145 prostate cancer cells and triggers a radical reorganization of the cell cytoskeleton. The small GTPase Rac1 is a master regulator of cytoskeleton organization and cell migration. We report that metformin leads to a major inhibition of Rac1 GTPase activity by interfering with some of its multiple upstream signaling pathways, namely P-Rex1 (a Guanine nucleotide exchange factor and activator of Rac1), cAMP, and CXCL12/CXCR4, resulting in decreased migration of prostate cancer cells. Importantly, overexpression of a constitutively active form of Rac1, or P-Rex, as well as the inhibition of the adenylate cyclase, was able to reverse the antimigratory effects of metformin. These results establish a novel mechanism of action for metformin and highlight its potential antimetastatic properties in prostate cancer.
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Affiliation(s)
- Béatrice Dirat
- INSERM, C3M, U1065, Team Cellular and Molecular Physiopathology of Obesity and Diabetes, Nice, France. Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France
| | - Isabelle Ader
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France. Université de Toulouse, UPS, IPBS, Toulouse, France
| | - Muriel Golzio
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France. Université de Toulouse, UPS, IPBS, Toulouse, France
| | - Fabienne Massa
- INSERM, C3M, U1065, Team Cellular and Molecular Physiopathology of Obesity and Diabetes, Nice, France. Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France
| | - Amel Mettouchi
- Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France. INSERM, C3M, U1065, Equipe Labellisée Ligue Contre le Cancer, Team Microtoxins in Host Pathogens Interactions, Nice, France
| | - Kathiane Laurent
- INSERM, C3M, U1065, Team Cellular and Molecular Physiopathology of Obesity and Diabetes, Nice, France. Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France
| | - Frédéric Larbret
- University of Nice Sophia Antipolis, EA6302, Flow Cytometry Facility, Hôpital l'Archet 1, Nice, France
| | - Bernard Malavaud
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France. Université de Toulouse, UPS, IPBS, Toulouse, France. Hôpital Rangueil, Service d'Urologie et de Transplantation Rénale, Toulouse, France
| | - Mireille Cormont
- INSERM, C3M, U1065, Team Cellular and Molecular Physiopathology of Obesity and Diabetes, Nice, France. Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France
| | - Emmanuel Lemichez
- Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France. INSERM, C3M, U1065, Equipe Labellisée Ligue Contre le Cancer, Team Microtoxins in Host Pathogens Interactions, Nice, France
| | - Olivier Cuvillier
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France. Université de Toulouse, UPS, IPBS, Toulouse, France
| | - Jean François Tanti
- INSERM, C3M, U1065, Team Cellular and Molecular Physiopathology of Obesity and Diabetes, Nice, France. Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France
| | - Frédéric Bost
- INSERM, C3M, U1065, Team Cellular and Molecular Physiopathology of Obesity and Diabetes, Nice, France. Univ. Nice Sophia Antipolis, C3M, U1065, Nice, France.
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Pan Y, Li X, Duan J, Yuan L, Fan S, Fan J, Xiaokaiti Y, Yang H, Wang Y, Li X. Enoxaparin sensitizes human non-small-cell lung carcinomas to gefitinib by inhibiting DOCK1 expression, vimentin phosphorylation, and Akt activation. Mol Pharmacol 2014; 87:378-90. [PMID: 25488183 DOI: 10.1124/mol.114.094425] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Gefitinib is widely used for the treatment of lung cancer in patients with sensitizing epidermal growth factor receptor mutations, but patients tend to develop resistance after an average of 10 months. Low molecular weight heparins, such as enoxaparin, potently inhibit experimental metastasis. This study aimed to determine the potential of combined enoxaparin and gefitinib (enoxaparin + gefitinib) treatment to inhibit tumor resistance to gefitinib both in vitro and in vivo. A549 and H1975 cell migration was analyzed in wound closure and Transwell assays. Akt and extracellular signal-related kinase 1/2 signaling pathways were identified, and a proteomics analysis was conducted using SDS-PAGE/liquid chromatography-tandem mass spectrometry analysis. Molecular interaction networks were visualized using the Cytoscape bioinformatics platform. Protein expression of dedicator of cytokinesis 1 (DOCK1) and cytoskeleton intermediate filament vimentin were identified using an enzyme-linked immunosorbent assay, Western blot, and small interfering RNA transfection of A549 cells. In xenograft A549-luc-C8 tumors in nude mice, enoxaparin + gefitinib inhibited tumor growth and reduced lung colony formation compared with gefitinib alone. Furthermore, the combination had stronger inhibitory effects on cell migration than either agent used individually. Additional enoxaparin administration resulted in better effective inhibition of Akt activity compared with gefitinib alone. Proteomics and network analysis implicated DOCK1 as the key node molecule. Western blot verified the effective inhibition of the expression of DOCK1 and vimentin phosphorylation by enoxaparin + gefitinib compared with gefitinib alone. DOCK1 knockdown confirmed its role in cell migration, Akt expression, and vimentin phosphorylation. Our data indicate that enoxaparin sensitizes gefitinib antitumor and antimigration activity in lung cancer by suppressing DOCK1 expression, Akt activity, and vimentin phosphorylation.
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Affiliation(s)
- Yan Pan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Xin Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Jianhui Duan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Lan Yuan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Shengjun Fan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Jingpu Fan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Yilixiati Xiaokaiti
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Haopeng Yang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Yefan Wang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
| | - Xuejun Li
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Health Science Center and Beijing Key Laboratory of Tumor Systems Biology, Peking University, Beijing, People's Republic of China (Y.P., X.L., J.D., S.F., J.F., Y.X., H.Y., Y.W., X.L.); and Medical and Healthy Analytical Center, Peking University Health Science Center, Beijing, People's Republic of China (L.Y.)
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Goicoechea SM, Awadia S, Garcia-Mata R. I'm coming to GEF you: Regulation of RhoGEFs during cell migration. Cell Adh Migr 2014; 8:535-49. [PMID: 25482524 PMCID: PMC4594598 DOI: 10.4161/cam.28721] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cell migration is a highly regulated multistep process that requires the coordinated regulation of cell adhesion, protrusion, and contraction. These processes require numerous protein–protein interactions and the activation of specific signaling pathways. The Rho family of GTPases plays a key role in virtually every aspect of the cell migration cycle. The activation of Rho GTPases is mediated by a large and diverse family of proteins; the guanine nucleotide exchange factors (RhoGEFs). GEFs work immediately upstream of Rho proteins to provide a direct link between Rho activation and cell–surface receptors for various cytokines, growth factors, adhesion molecules, and G protein-coupled receptors. The regulated targeting and activation of RhoGEFs is essential to coordinate the migratory process. In this review, we summarize the recent advances in our understanding of the role of RhoGEFs in the regulation of cell migration.
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Key Words
- DH, Dbl-homology
- DHR, DOCK homology region
- DOCK, dedicator of cytokinesis
- ECM, extracellular matrix
- EGF, epidermal growth factor
- FA, focal adhesion
- FN, fibronectin
- GAP, GTPase activating protein
- GDI, guanine nucleotide dissociation inhibitor
- GEF, guanine nucleotide exchange factor
- GPCR, G protein-coupled receptor
- HGF, hepatocyte growth factor
- LPA, lysophosphatidic acid
- MII, myosin II
- PA, phosphatidic acid
- PDGF, platelet-derived growth factor
- PH, pleckstrin-homology
- PIP2, phosphatidylinositol 4, 5-bisphosphate
- PIP3, phosphatidylinositol (3, 4, 5)-trisphosphate.
- Rho GEFs
- Rho GTPases
- bFGF, basic fibroblast growth factor
- cell migration
- cell polarization
- focal adhesions
- guanine nucleotide exchange factors
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Affiliation(s)
- Silvia M Goicoechea
- a Department of Biological Sciences ; University of Toledo ; Toledo , OH USA
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90
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ELMO1 is upregulated in AML CD34+ stem/progenitor cells, mediates chemotaxis and predicts poor prognosis in normal karyotype AML. PLoS One 2014; 9:e111568. [PMID: 25360637 PMCID: PMC4216115 DOI: 10.1371/journal.pone.0111568] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 10/03/2014] [Indexed: 12/27/2022] Open
Abstract
Both normal as well leukemic hematopoietic stem cells critically depend on their microenvironment in the bone marrow for processes such as self-renewal, survival and differentiation, although the exact pathways that are involved remain poorly understood. We performed transcriptome analysis on primitive CD34+ acute myeloid leukemia (AML) cells (n = 46), their more differentiated CD34- leukemic progeny, and normal CD34+ bone marrow cells (n = 31) and focused on differentially expressed genes involved in adhesion and migration. Thus, Engulfment and Motility protein 1 (ELMO1) was identified amongst the top 50 most differentially expressed genes. ELMO1 is a crucial link in the signaling cascade that leads to activation of RAC GTPases and cytoskeleton rearrangements. We confirmed increased ELMO1 expression at the mRNA and protein level in a panel of AML samples and showed that high ELMO1 expression is an independent negative prognostic factor in normal karyotype (NK) AML in three large independent patient cohorts. Downmodulation of ELMO1 in human CB CD34+ cells did not significantly alter expansion, progenitor frequency or differentiation in stromal co-cultures, but did result in a decreased frequency of stem cells in LTC-IC assays. In BCR-ABL-transduced human CB CD34+ cells depletion of ELMO1 resulted in a mild decrease in proliferation, but replating capacity of progenitors was severely impaired. Downregulation of ELMO1 in a panel of primary CD34+ AML cells also resulted in reduced long-term growth in stromal co-cultures in two out of three cases. Pharmacological inhibition of the ELMO1 downstream target RAC resulted in a severely impaired proliferation and survival of leukemic cells. Finally, ELMO1 depletion caused a marked decrease in SDF1-induced chemotaxis of leukemic cells. Taken together, these data show that inhibiting the ELMO1-RAC axis might be an alternative way to target leukemic cells.
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91
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Canonical and noncanonical g-protein signaling helps coordinate actin dynamics to promote macrophage phagocytosis of zymosan. Mol Cell Biol 2014; 34:4186-99. [PMID: 25225330 DOI: 10.1128/mcb.00325-14] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Both chemotaxis and phagocytosis depend upon actin-driven cell protrusions and cell membrane remodeling. While chemoattractant receptors rely upon canonical G-protein signaling to activate downstream effectors, whether such signaling pathways affect phagocytosis is contentious. Here, we report that Gαi nucleotide exchange and signaling helps macrophages coordinate the recognition, capture, and engulfment of zymosan bioparticles. We show that zymosan exposure recruits F-actin, Gαi proteins, and Elmo1 to phagocytic cups and early phagosomes. Zymosan triggered an increase in intracellular Ca(2+) that was partially sensitive to Gαi nucleotide exchange inhibition and expression of GTP-bound Gαi recruited Elmo1 to the plasma membrane. Reducing GDP-Gαi nucleotide exchange, decreasing Gαi expression, pharmacologically interrupting Gβγ signaling, or reducing Elmo1 expression all impaired phagocytosis, while favoring the duration that Gαi remained GTP bound promoted it. Our studies demonstrate that targeting heterotrimeric G-protein signaling offers opportunities to enhance or retard macrophage engulfment of phagocytic targets such as zymosan.
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92
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Lee J, Park B, Kim G, Kim K, Pak J, Kim K, Ye MB, Park SG, Park D. Arhgef16, a novel Elmo1 binding partner, promotes clearance of apoptotic cells via RhoG-dependent Rac1 activation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:2438-47. [PMID: 25063526 DOI: 10.1016/j.bbamcr.2014.07.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 07/11/2014] [Accepted: 07/15/2014] [Indexed: 12/21/2022]
Abstract
Elmo is an evolutionarily conserved mammalian ortholog of Caenorhabditis elegans CED-12 with proposed roles during the removal of apoptotic cells, cell migration, neurite outgrowth, and myoblast fusion (Katoh and Negishi (2003) [1], Park and Tosello (2007) [2], Grimsley et al. (2004) [3], Hamoud et al. (2014) [4]). Elmo mediates these cellular processes by interacting with various proteins located in the plasma membrane, cytoplasm and nucleus, and by modulating their activities although it has no intrinsic catalytic activity (Park and Tosello (2007) [2], Hamoud et al. (2014) [4], Li et al. (2013) [5], Margaron, Fradet and Cote (2013) [6], and Mauldin et al. (2013)[7]). Because there are a limited number of proteins known to interact with Elmo, we performed a yeast two-hybrid screen using Elmo1 as bait to identify Elmo1-interacting proteins and to evaluate their mode of regulation. Arhgef16 was one of the proteins identified through the screen and subsequent analyses revealed that Arhgef16 interacted with Elmo1 in mammalian cells as well. Expression of Arhgef16 in phagocytes promoted engulfment of apoptotic cells, and engulfment mediated by Arhgef16 increased synergistically in the presence of Elmo1 but was abrogated in the absence of Elmo1. In addition, Arhgef16-mediated removal of apoptotic cells was dependent on RhoG, but independent of Dock1. Taken together, this study suggests that the newly identified Elmo1-interacting protein, Arhgef16, functions synergistically with Elmo1 to promote clearance of apoptotic cells in a RhoG-dependent and Dock1-independent manner.
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Affiliation(s)
- Juyeon Lee
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Boyeon Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Gayoung Kim
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Kwangwoo Kim
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Jeongjun Pak
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Kwanhyeong Kim
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Michael B Ye
- School of Liberal Arts and Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea
| | - Sung-Gyoo Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea
| | - Daeho Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea.
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93
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Namekata K, Kimura A, Kawamura K, Harada C, Harada T. Dock GEFs and their therapeutic potential: neuroprotection and axon regeneration. Prog Retin Eye Res 2014; 43:1-16. [PMID: 25016980 DOI: 10.1016/j.preteyeres.2014.06.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/26/2014] [Accepted: 06/30/2014] [Indexed: 12/17/2022]
Abstract
The dedicator of cytokinesis (Dock) family is composed of atypical guanine exchange factors (GEFs) that activate the Rho GTPases Rac1 and Cdc42. Rho GTPases are best documented for their roles in actin polymerization and they regulate important cellular functions, including morphogenesis, migration, neuronal development, and cell division and adhesion. To date, 11 Dock family members have been identified and their roles have been reported in diverse contexts. There has been increasing interest in elucidating the roles of Dock proteins in recent years and studies have revealed that they are potential therapeutic targets for various diseases, including glaucoma, Alzheimer's disease, cancer, attention deficit hyperactivity disorder and combined immunodeficiency. Among the Dock proteins, Dock3 is predominantly expressed in the central nervous system and recent studies have revealed that Dock3 plays a role in protecting retinal ganglion cells from neurotoxicity and oxidative stress as well as in promoting optic nerve regeneration. In this review, we discuss the current understanding of the 11 Dock GEFs and their therapeutic potential, with a particular focus on Dock3 as a novel target for the treatment of glaucoma and other neurodegenerative diseases.
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Affiliation(s)
- Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Kazuto Kawamura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
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94
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Gadea G, Blangy A. Dock-family exchange factors in cell migration and disease. Eur J Cell Biol 2014; 93:466-77. [PMID: 25022758 DOI: 10.1016/j.ejcb.2014.06.003] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/10/2014] [Accepted: 06/17/2014] [Indexed: 02/06/2023] Open
Abstract
Dock family proteins are evolutionary conserved exchange factors for the Rho GTPases Rac and Cdc42. There are 11 Dock proteins in mammals, named Dock1 (or Dock180) to Dock11 that play different cellular functions. In particular, Dock proteins regulate actin cytoskeleton, cell adhesion and migration. Not surprisingly, members of the Dock family have been involved in various pathologies, including cancer and defects in the central nervous and immune systems. This review proposes an update of the recent findings regarding the function of Dock proteins, focusing on their role in the control of cell migration and invasion and the consequences in human diseases.
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Affiliation(s)
- Gilles Gadea
- CNRS UMR 5237, Centre de Recherche de Biochimie Macromoléculaire, France; Montpellier University, France
| | - Anne Blangy
- CNRS UMR 5237, Centre de Recherche de Biochimie Macromoléculaire, France; Montpellier University, France.
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95
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O'Neill PR, Gautam N. Subcellular optogenetic inhibition of G proteins generates signaling gradients and cell migration. Mol Biol Cell 2014; 25:2305-14. [PMID: 24920824 PMCID: PMC4116304 DOI: 10.1091/mbc.e14-04-0870] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cells sense gradients of extracellular cues and generate polarized responses such as cell migration and neurite initiation. There is static information on the intracellular signaling molecules involved in these responses, but how they dynamically orchestrate polarized cell behaviors is not well understood. A limitation has been the lack of methods to exert spatial and temporal control over specific signaling molecules inside a living cell. Here we introduce optogenetic tools that act downstream of native G protein-coupled receptor (GPCRs) and provide direct control over the activity of endogenous heterotrimeric G protein subunits. Light-triggered recruitment of a truncated regulator of G protein signaling (RGS) protein or a Gβγ-sequestering domain to a selected region on the plasma membrane results in localized inhibition of G protein signaling. In immune cells exposed to spatially uniform chemoattractants, these optogenetic tools allow us to create reversible gradients of signaling activity. Migratory responses generated by this approach show that a gradient of active G protein αi and βγ subunits is sufficient to generate directed cell migration. They also provide the most direct evidence so for a global inhibition pathway triggered by Gi signaling in directional sensing and adaptation. These optogenetic tools can be applied to interrogate the mechanistic basis of other GPCR-modulated cellular functions.
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Affiliation(s)
- Patrick R O'Neill
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | - N Gautam
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
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96
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Rainero E, Cianflone C, Porporato PE, Chianale F, Malacarne V, Bettio V, Ruffo E, Ferrara M, Benecchia F, Capello D, Paster W, Locatelli I, Bertoni A, Filigheddu N, Sinigaglia F, Norman JC, Baldanzi G, Graziani A. The diacylglycerol kinase α/atypical PKC/β1 integrin pathway in SDF-1α mammary carcinoma invasiveness. PLoS One 2014; 9:e97144. [PMID: 24887021 PMCID: PMC4041662 DOI: 10.1371/journal.pone.0097144] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 04/15/2014] [Indexed: 12/11/2022] Open
Abstract
Diacylglycerol kinase α (DGKα), by phosphorylating diacylglycerol into phosphatidic acid, provides a key signal driving cell migration and matrix invasion. We previously demonstrated that in epithelial cells activation of DGKα activity promotes cytoskeletal remodeling and matrix invasion by recruiting atypical PKC at ruffling sites and by promoting RCP-mediated recycling of α5β1 integrin to the tip of pseudopods. In here we investigate the signaling pathway by which DGKα mediates SDF-1α-induced matrix invasion of MDA-MB-231 invasive breast carcinoma cells. Indeed we showed that, following SDF-1α stimulation, DGKα is activated and localized at cell protrusion, thus promoting their elongation and mediating SDF-1α induced MMP-9 metalloproteinase secretion and matrix invasion. Phosphatidic acid generated by DGKα promotes localization at cell protrusions of atypical PKCs which play an essential role downstream of DGKα by promoting Rac-mediated protrusion elongation and localized recruitment of β1 integrin and MMP-9. We finally demonstrate that activation of DGKα, atypical PKCs signaling and β1 integrin are all essential for MDA-MB-231 invasiveness. These data indicates the existence of a SDF-1α induced DGKα - atypical PKC - β1 integrin signaling pathway, which is essential for matrix invasion of carcinoma cells.
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Affiliation(s)
- Elena Rainero
- Integrin Biology Laboratory, Beatson Institute for Cancer Research, Glasgow, Scotland, United Kingdom
| | - Cristina Cianflone
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | | | - Federica Chianale
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Valeria Malacarne
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Valentina Bettio
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Elisa Ruffo
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Michele Ferrara
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Fabio Benecchia
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Daniela Capello
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Wolfgang Paster
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Irene Locatelli
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Alessandra Bertoni
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Nicoletta Filigheddu
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Fabiola Sinigaglia
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Jim C. Norman
- Integrin Biology Laboratory, Beatson Institute for Cancer Research, Glasgow, Scotland, United Kingdom
| | - Gianluca Baldanzi
- Integrin Biology Laboratory, Beatson Institute for Cancer Research, Glasgow, Scotland, United Kingdom
| | - Andrea Graziani
- Integrin Biology Laboratory, Beatson Institute for Cancer Research, Glasgow, Scotland, United Kingdom
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97
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Stevenson C, de la Rosa G, Anderson CS, Murphy PS, Capece T, Kim M, Elliott MR. Essential role of Elmo1 in Dock2-dependent lymphocyte migration. THE JOURNAL OF IMMUNOLOGY 2014; 192:6062-70. [PMID: 24821968 DOI: 10.4049/jimmunol.1303348] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Elmo1 and Elmo2 are highly homologous cytoplasmic adaptor proteins that interact with Dock family guanine nucleotide exchange factors to promote activation of the small GTPase Rac. In T lymphocytes, Dock2 is essential for CCR7- and CXCR4-dependent Rac activation and chemotaxis, but the role of Elmo proteins in regulating Dock2 function in primary T cells is not known. In this article, we show that endogenous Elmo1, but not Elmo2, interacts constitutively with Dock2 in mouse and human primary T cells. CD4(+) T cells from Elmo1(-/-) mice were profoundly impaired in polarization, Rac activation, and chemotaxis in response to CCR7 and CXCR4 stimulation. Transfection of full-length Elmo1, but not Elmo2 or a Dock2-binding mutant of Elmo1, rescued defective migration of Elmo1(-/-) T cells. Interestingly, Dock2 protein levels were reduced by 4-fold in Elmo1(-/-) lymphocytes despite normal levels of Dock2 mRNA. Dock2 polyubiquitination was increased in Elmo1(-/-) T cells, and treatment with proteasome inhibitors partially restored Dock2 levels in Elmo1(-/-) T cells. Finally, we show that Dock2 is directly ubiquitinated in CD4(+) T cells and that Elmo1 expression in heterologous cells inhibits ubiquitination of Dock2. Taken together, these findings reveal a previously unknown, nonredundant role for Elmo1 in controlling Dock2 levels and Dock2-dependent T cell migration in primary lymphocytes. Inhibition of Dock2 has therapeutic potential as a means to control recruitment of pathogenic lymphocytes in diseased tissues. This work provides valuable insights into the molecular regulation of Dock2 by Elmo1 that can be used to design improved inhibitors that target the Elmo-Dock-Rac signaling complex.
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Affiliation(s)
- Catherine Stevenson
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
| | - Gonzalo de la Rosa
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
| | - Christopher S Anderson
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
| | - Patrick S Murphy
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
| | - Tara Capece
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
| | - Minsoo Kim
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
| | - Michael R Elliott
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642; and David H. Smith Center for Vaccine Biology and Imunology, University of Rochester Medical Center, Rochester, NY 14642
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98
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Abstract
Rho GTPases regulate many essential processes during development, yet the full impact of their upstream regulation through guanine nucleotide exchange factors (GEFs) is only beginning to be appreciated. In this review, Laurin and Côté focus on emerging biological functions of the mammalian Dock family of GEFs in development and disease and discuss how recent discoveries might be exploited for novel therapeutic strategies. Rho GTPases play key regulatory roles in many aspects of embryonic development, regulating processes such as differentiation, proliferation, morphogenesis, and migration. Two families of guanine nucleotide exchange factors (GEFs) found in metazoans, Dbl and Dock, are responsible for the spatiotemporal activation of Rac and Cdc42 proteins and their downstream signaling pathways. This review focuses on the emerging roles of the mammalian DOCK family in development and disease. We also discuss, when possible, how recent discoveries concerning the biological functions of these GEFs might be exploited for the development of novel therapeutic strategies.
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Affiliation(s)
- Mélanie Laurin
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, Quebec H2W 1R7, Canada
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99
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Kristensen LS, Søes S, Hansen LL. ELMO3: a direct driver of cancer metastasis? Cell Cycle 2014; 13:2483-4. [PMID: 25486185 PMCID: PMC4614988 DOI: 10.4161/15384101.2014.947228] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 06/30/2014] [Accepted: 07/02/2014] [Indexed: 12/31/2022] Open
Affiliation(s)
| | - Signe Søes
- Department of Biomedicine; University of Aarhus; Aarhus C, Denmark
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100
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Jin T. Gradient sensing during chemotaxis. Curr Opin Cell Biol 2013; 25:532-7. [PMID: 23880435 DOI: 10.1016/j.ceb.2013.06.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 06/18/2013] [Accepted: 06/19/2013] [Indexed: 11/17/2022]
Abstract
Eukaryotic cells have the ability to sense chemoattractant gradients and to migrate toward the sources of attractants. The chemical gradient-guided cell movement is referred to as chemotaxis. Chemoattractants are detected by members of G-protein-coupled receptors (GPCRs) that link to heterotrimeric G-proteins. The GPCR/G-protein sensing machinery is able to translate external chemoattractants fields into intercellular cues, which direct reorganization of the actin cytoskeleton that drives cell movement. Here, I review our current understanding of the formation of chemoattractant gradients in vivo, the GPCR-mediated gradient sensing, and the sophisticated signaling network that guides the function of the actin cytoskeleton.
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Affiliation(s)
- Tian Jin
- Chemotaxis Signal Section, Laboratory of Immunogenetics, NIAID, NIH, Twinbrook II Facility, 12441 Parklawn Drive, Rockville, MD 20852, United States.
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