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Duchatel RJ, Jackson ER, Parackal SG, Kiltschewskij D, Findlay IJ, Mannan A, Staudt DE, Thomas BC, Germon ZP, Laternser S, Kearney PS, Jamaluddin MFB, Douglas AM, Beitaki T, McEwen HP, Persson ML, Hocke EA, Jain V, Aksu M, Manning EE, Murray HC, Verrills NM, Sun CX, Daniel P, Vilain RE, Skerrett-Byrne DA, Nixon B, Hua S, de Bock CE, Colino-Sanguino Y, Valdes-Mora F, Tsoli M, Ziegler DS, Cairns MJ, Raabe EH, Vitanza NA, Hulleman E, Phoenix TN, Koschmann C, Alvaro F, Dayas CV, Tinkle CL, Wheeler H, Whittle JR, Eisenstat DD, Firestein R, Mueller S, Valvi S, Hansford JR, Ashley DM, Gregory SG, Kilburn LB, Nazarian J, Cain JE, Dun MD. PI3K/mTOR is a therapeutically targetable genetic dependency in diffuse intrinsic pontine glioma. J Clin Invest 2024; 134:e170329. [PMID: 38319732 PMCID: PMC10940093 DOI: 10.1172/jci170329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 01/11/2024] [Indexed: 02/08/2024] Open
Abstract
Diffuse midline glioma (DMG), including tumors diagnosed in the brainstem (diffuse intrinsic pontine glioma; DIPG), are uniformly fatal brain tumors that lack effective treatment. Analysis of CRISPR/Cas9 loss-of-function gene deletion screens identified PIK3CA and MTOR as targetable molecular dependencies across patient derived models of DIPG, highlighting the therapeutic potential of the blood-brain barrier-penetrant PI3K/Akt/mTOR inhibitor, paxalisib. At the human-equivalent maximum tolerated dose, mice treated with paxalisib experienced systemic glucose feedback and increased insulin levels commensurate with patients using PI3K inhibitors. To exploit genetic dependence and overcome resistance while maintaining compliance and therapeutic benefit, we combined paxalisib with the antihyperglycemic drug metformin. Metformin restored glucose homeostasis and decreased phosphorylation of the insulin receptor in vivo, a common mechanism of PI3K-inhibitor resistance, extending survival of orthotopic models. DIPG models treated with paxalisib increased calcium-activated PKC signaling. The brain penetrant PKC inhibitor enzastaurin, in combination with paxalisib, synergistically extended the survival of multiple orthotopic patient-derived and immunocompetent syngeneic allograft models; benefits potentiated in combination with metformin and standard-of-care radiotherapy. Therapeutic adaptation was assessed using spatial transcriptomics and ATAC-Seq, identifying changes in myelination and tumor immune microenvironment crosstalk. Collectively, this study has identified what we believe to be a clinically relevant DIPG therapeutic combinational strategy.
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Affiliation(s)
- Ryan J. Duchatel
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
| | - Evangeline R. Jackson
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
| | - Sarah G. Parackal
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Dylan Kiltschewskij
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Izac J. Findlay
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
| | - Abdul Mannan
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Dilana E. Staudt
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
| | - Bryce C. Thomas
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
| | - Zacary P. Germon
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Sandra Laternser
- DIPG/DMG Research Center Zurich, Children’s Research Center, Department of Pediatrics, University Children’s Hospital Zürich, Zurich, Switzerland
| | - Padraic S. Kearney
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - M. Fairuz B. Jamaluddin
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Alicia M. Douglas
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Tyrone Beitaki
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Holly P. McEwen
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Mika L. Persson
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
| | - Emily A. Hocke
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Vaibhav Jain
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Michael Aksu
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Elizabeth E. Manning
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Heather C. Murray
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Nicole M. Verrills
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Claire Xin Sun
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Paul Daniel
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Ricardo E. Vilain
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - David A. Skerrett-Byrne
- Infertility and Reproduction Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Brett Nixon
- Infertility and Reproduction Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Susan Hua
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Charles E. de Bock
- Children’s Cancer Institute, University of New South Wales (UNSW) Sydney, Kensington, New South Wales, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, New South Wales, Australia
| | - Yolanda Colino-Sanguino
- Children’s Cancer Institute, University of New South Wales (UNSW) Sydney, Kensington, New South Wales, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, New South Wales, Australia
| | - Fatima Valdes-Mora
- Children’s Cancer Institute, University of New South Wales (UNSW) Sydney, Kensington, New South Wales, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, New South Wales, Australia
| | - Maria Tsoli
- Children’s Cancer Institute, University of New South Wales (UNSW) Sydney, Kensington, New South Wales, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, New South Wales, Australia
| | - David S. Ziegler
- Children’s Cancer Institute, University of New South Wales (UNSW) Sydney, Kensington, New South Wales, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, New South Wales, Australia
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, New South Wales, Australia
| | - Murray J. Cairns
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Eric H. Raabe
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nicholas A. Vitanza
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, Seattle, Washington, USA
- Department of Pediatrics, Seattle Children’s Hospital, University of Washington, Seattle, Washington, USA
| | - Esther Hulleman
- Princess Máxima Center for Pediatric Oncology, Utrecht, Netherlands
| | - Timothy N. Phoenix
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of Cincinnati, Cincinnati, Ohio, USA
| | - Carl Koschmann
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, University of Michigan, Ann Arbor, Michigan, USA
| | - Frank Alvaro
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- John Hunter Children’s Hospital, New Lambton Heights, New South Wales, Australia
| | - Christopher V. Dayas
- School of Biomedical Science and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
| | - Christopher L. Tinkle
- Department of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Helen Wheeler
- Department of Radiation Oncology Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, New South Wales, Australia
- The Brain Cancer group, St Leonards, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, Australia
| | - James R. Whittle
- Department of Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
- Personalised Oncology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - David D. Eisenstat
- Children’s Cancer Centre, The Royal Children’s Hospital Melbourne, Parkville, Victoria, Australia
- Neuro-Oncology Laboratory, Murdoch Children’s Research Institute, Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - Ron Firestein
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Sabine Mueller
- DIPG/DMG Research Center Zurich, Children’s Research Center, Department of Pediatrics, University Children’s Hospital Zürich, Zurich, Switzerland
- Department of Neurology, Neurosurgery, and Pediatrics, University of California, San Francisco, California, USA
| | - Santosh Valvi
- Department of Paediatric and Adolescent Oncology/Haematology, Perth Children’s Hospital, Nedlands, Washington, Australia
- Brain Tumour Research Laboratory, Telethon Kids Institute, Nedlands, Washington, Australia
- Division of Paediatrics, University of Western Australia Medical School, Nedlands, Western Australia, Australia
| | - Jordan R. Hansford
- Michael Rice Centre for Hematology and Oncology, Women’s and Children’s Hospital, North Adelaide, South Australia, Australia
- South Australia Health and Medical Research Institute, Adelaide, South Australia, Australia
- South Australian Immunogenomics Cancer Institute, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - David M. Ashley
- The Preston Robert Tisch Brain Tumor Center at Duke, Department of Neurosurgery, Duke University, Durham, North Carolina, USA
| | - Simon G. Gregory
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, North Carolina, USA
- The Preston Robert Tisch Brain Tumor Center at Duke, Department of Neurosurgery, Duke University, Durham, North Carolina, USA
| | - Lindsay B. Kilburn
- Center for Genetic Medicine Research, Children’s National Hospital, Washington, DC, USA
- The George Washington University, School of Medicine and Health Sciences, Washington, DC, USA
| | - Javad Nazarian
- DIPG/DMG Research Center Zurich, Children’s Research Center, Department of Pediatrics, University Children’s Hospital Zürich, Zurich, Switzerland
- Center for Genetic Medicine Research, Children’s National Hospital, Washington, DC, USA
- The George Washington University, School of Medicine and Health Sciences, Washington, DC, USA
| | - Jason E. Cain
- Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Matthew D. Dun
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, New South Wales, Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Paediatric Stream, Mark Hughes Foundation Centre for Brain Cancer Research, College of Health, Medicine, and Wellbeing, Callaghan, New South Wales, Australia
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Krajnik A, Brazzo JA, Vaidyanathan K, Das T, Redondo-Muñoz J, Bae Y. Phosphoinositide Signaling and Mechanotransduction in Cardiovascular Biology and Disease. Front Cell Dev Biol 2020; 8:595849. [PMID: 33381504 PMCID: PMC7767973 DOI: 10.3389/fcell.2020.595849] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/25/2020] [Indexed: 12/14/2022] Open
Abstract
Phosphoinositides, which are membrane-bound phospholipids, are critical signaling molecules located at the interface between the extracellular matrix, cell membrane, and cytoskeleton. Phosphoinositides are essential regulators of many biological and cellular processes, including but not limited to cell migration, proliferation, survival, and differentiation, as well as cytoskeletal rearrangements and actin dynamics. Over the years, a multitude of studies have uniquely implicated phosphoinositide signaling as being crucial in cardiovascular biology and a dominant force in the development of cardiovascular disease and its progression. Independently, the cellular transduction of mechanical forces or mechanotransduction in cardiovascular cells is widely accepted to be critical to their homeostasis and can drive aberrant cellular phenotypes and resultant cardiovascular disease. Given the versatility and diversity of phosphoinositide signaling in the cardiovascular system and the dominant regulation of cardiovascular cell functions by mechanotransduction, the molecular mechanistic overlap and extent to which these two major signaling modalities converge in cardiovascular cells remain unclear. In this review, we discuss and synthesize recent findings that rightfully connect phosphoinositide signaling to cellular mechanotransduction in the context of cardiovascular biology and disease, and we specifically focus on phosphatidylinositol-4,5-phosphate, phosphatidylinositol-4-phosphate 5-kinase, phosphatidylinositol-3,4,5-phosphate, and phosphatidylinositol 3-kinase. Throughout the review, we discuss how specific phosphoinositide subspecies have been shown to mediate biomechanically sensitive cytoskeletal remodeling in cardiovascular cells. Additionally, we discuss the direct interaction of phosphoinositides with mechanically sensitive membrane-bound ion channels in response to mechanical stimuli. Furthermore, we explore the role of phosphoinositide subspecies in association with critical downstream effectors of mechanical signaling in cardiovascular biology and disease.
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Affiliation(s)
- Amanda Krajnik
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Joseph A Brazzo
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Kalyanaraman Vaidyanathan
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Tuhin Das
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Javier Redondo-Muñoz
- Department of Molecular Biomedicine, Centro de Investigaciones Biológicas Margarita Salas, Madrid, Spain.,Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Yongho Bae
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
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Restoration of MARCKS enhances chemosensitivity in cancer. J Cancer Res Clin Oncol 2020; 146:843-858. [PMID: 32056006 PMCID: PMC7085482 DOI: 10.1007/s00432-020-03149-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/04/2020] [Indexed: 11/23/2022]
Abstract
Purpose Increased ATP-binding-cassette (ABC) transporter activity is a major cause of chemotherapy resistance in cancer. The ABC transporter family member ABCB1 is often overexpressed in colorectal cancer (CRC). Phosphatidylinositol-4,5-bisphosphat (PI(4,5)P2)-dependent pathways are involved in the regulation of ABCB1 function. The protein Myristoylated Alanine-Rich C-Kinase Substrate (MARCKS) is a pivotal regulator of PI(4,5)P2 and inactivated in many CRC cancers via genetic deletion or hyperphosphorylation. Therefore, MARCKS may critically impact ABCB1. Methods CRC samples as well as CRC cell lines were tested for a connection between MARCKS and ABCB1 via immunofluorescence and Western-blot analysis. ABCB1 function was studied via calcein influx assay under treatment with known ABCB1 inhibitors (verapamil, tariquidar) as well as the kinase inhibitor bosutinib. ABCB1 internalization and MARCKS translocation was analyzed via confocal microscopy exploiting the endocytosis inhibitors chlorpromazine and dynasore. Abundance of PI(4,5)P2 was monitored by intramolecular fluorescence resonance energy transfer (FRET). Reproductive cell survival was studied via colorimetric WST-1 and clonogenic assays in combination with exposure to the chemotherapeutics doxorubicin and 5-fuorouracil (5-FU). Results We found increased ABCB1 expression in MARCKS negative CRC patient tumor samples and established CRC cell lines. Mechanistically, the reconstitution of MARCKS function via recombinant expression or the pharmacological inhibition of MARCKS phosphorylation led to a substantial decrease in ABCB1 activity. In CRC cells, bosutinib treatment resulted in a MARCKS translocation from the cytosol to the plasma membrane, while simultaneously, ABCB1 was relocated to intracellular compartments. Inhibition of MARCKS phosphorylation via bosutinib rendered cells more sensitive to the chemotherapeutics doxorubicin and 5-FU. Conclusions Cells devoid of MARCKS function showed incomplete ABCB1 internalization, leading to higher ABCB1 activity enhancing chemoresistance. Vice versa our data suggest the prevention of MARCKS inhibition by reversing hyperphosphorylation or genomic restoration after deletion as two promising approaches to overcome tumor cell resistance towards chemotherapeutic ABCB1 substrates.
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Liang W, Gao R, Yang M, Wang X, Cheng K, Shi X, He C, Li Y, Wu Y, Shi L, Chen J, Yu X. MARCKSL1 promotes the proliferation, migration and invasion of lung adenocarcinoma cells. Oncol Lett 2020; 19:2272-2280. [PMID: 32194726 PMCID: PMC7039154 DOI: 10.3892/ol.2020.11313] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 08/06/2019] [Indexed: 12/24/2022] Open
Abstract
Lung cancer is the most common cancer in males and females and ~40% of lung cancer cases are adenocarcinomas. Previous studies have demonstrated that myristoylated alanine rich protein kinase C substrate (MARCKS) is upregulated in several types of cancer and is associated with poor prognosis in patients with breast cancer. However, its expression level and role in lung adenocarcinoma remain unknown. Therefore, the aim of the present study was to investigate the expression level and biological functions of MARCKS like 1 (MARCKSL1), a member of the MARCKS family, in lung adenocarcinoma. The expression level of MARCKSL1 was examined in human lung adenocarcinoma tissues and cell lines. MARCKSL1-specific small interfering RNAs effectively suppressed its expression level and significantly inhibited the proliferation, migration and invasion of lung adenocarcinoma cells. Additionally, the role of MARCKSLI in the regulation of metastasis was examined. Silencing MARCKSL1 decreased the expression of the epithelial-mesenchymal transition (EMT)-associated proteins E-cadherin, N-cadherin, vimentin and snail family transcriptional repressor 2, and decreased the phosphorylation level of AKT. The results obtained in the current study suggested that MARCKSL1 promoted the progression of lung adenocarcinoma by regulating EMT. MARCKSLI may have prognostic value and serve as a novel therapeutic target in lung adenocarcinoma.
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Affiliation(s)
- Wenjun Liang
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Ruichen Gao
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Mingxia Yang
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Xiaohua Wang
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Kewei Cheng
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Xuejun Shi
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Chen He
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Yemei Li
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Yuying Wu
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Lei Shi
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Jingtao Chen
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
| | - Xiaowei Yu
- Department of Respiratory Medicine, Affiliated Changzhou Second Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China
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Sheats MK, Yin Q, Fang S, Park J, Crews AL, Parikh I, Dickson B, Adler KB. MARCKS and Lung Disease. Am J Respir Cell Mol Biol 2019; 60:16-27. [PMID: 30339463 DOI: 10.1165/rcmb.2018-0285tr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
MARCKS (myristoylated alanine-rich C kinase substrate) is a prominent PKC substrate expressed in all eukaryotic cells. It is known to bind to and cross-link actin filaments, to serve as a bridge between Ca2+/calmodulin and PKC signaling, and to sequester the signaling molecule phosphatidylinositol 4,5-bisphosphate in the plasma membrane. Since the mid-1980s, this evolutionarily conserved and ubiquitously expressed protein has been associated with regulating cellular events that require dynamic actin reorganization, including cellular adhesion, migration, and exocytosis. More recently, translational studies have implicated MARCKS in the pathophysiology of a number of airway diseases, including chronic obstructive pulmonary disease, asthma, lung cancer, and acute lung injury/acute respiratory distress syndrome. This article summarizes the structure and cellular function of MARCKS (also including MARCKS family proteins and MARCKSL1 [MARCKS-like protein 1]). Evidence for MARCKS's role in several lung diseases is discussed, as are the technological innovations that took MARCKS-targeting strategies from theoretical to therapeutic. Descriptions and updates derived from ongoing clinical trials that are investigating inhalation of a MARCKS-targeting peptide as therapy for patients with chronic bronchitis, lung cancer, and ARDS are provided.
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Affiliation(s)
| | - Qi Yin
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Shijing Fang
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Joungjoa Park
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Anne L Crews
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Indu Parikh
- 3 BioMarck Pharmaceuticals, Durham, North Carolina
| | | | - Kenneth B Adler
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
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El Amri M, Fitzgerald U, Schlosser G. MARCKS and MARCKS-like proteins in development and regeneration. J Biomed Sci 2018; 25:43. [PMID: 29788979 PMCID: PMC5964646 DOI: 10.1186/s12929-018-0445-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/07/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Myristoylated Alanine-Rich C-kinase Substrate (MARCKS) and MARCKS-like protein 1 (MARCKSL1) have a wide range of functions, ranging from roles in embryonic development to adult brain plasticity and the inflammatory response. Recently, both proteins have also been identified as important players in regeneration. Upon phosphorylation by protein kinase C (PKC) or calcium-dependent calmodulin-binding, MARCKS and MARCKSL1 translocate from the membrane into the cytosol, modulating cytoskeletal actin dynamics and vesicular trafficking and activating various signal transduction pathways. As a consequence, the two proteins are involved in the regulation of cell migration, secretion, proliferation and differentiation in many different tissues. MAIN BODY Throughout vertebrate development, MARCKS and MARCKSL1 are widely expressed in tissues derived from all germ layers, with particularly strong expression in the nervous system. They have been implicated in the regulation of gastrulation, myogenesis, brain development, and other developmental processes. Mice carrying loss of function mutations in either Marcks or Marcksl1 genes die shortly after birth due to multiple deficiencies including detrimental neural tube closure defects. In adult vertebrates, MARCKS and MARCKL1 continue to be important for multiple regenerative processes including peripheral nerve, appendage, and tail regeneration, making them promising targets for regenerative medicine. CONCLUSION This review briefly summarizes the molecular interactions and cellular functions of MARCKS and MARCKSL1 proteins and outlines their vital roles in development and regeneration.
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Affiliation(s)
- Mohamed El Amri
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Biomedical Sciences Building, Newcastle Road, Galway, Ireland
| | - Una Fitzgerald
- Galway Neuroscience Centre, School of Natural Sciences, Biomedical Sciences Building, National University of Ireland, Newcastle Road, Galway, Ireland
| | - Gerhard Schlosser
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Biomedical Sciences Building, Newcastle Road, Galway, Ireland. .,School of Natural Sciences and Regenerative Medicine Institute (REMEDI), National University of Ireland, Galway, Biomedical Sciences Building, Newcastle Road, Galway, Ireland.
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Failla CM, Carbo M, Morea V. Positive and Negative Regulation of Angiogenesis by Soluble Vascular Endothelial Growth Factor Receptor-1. Int J Mol Sci 2018; 19:ijms19051306. [PMID: 29702562 PMCID: PMC5983705 DOI: 10.3390/ijms19051306] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 04/23/2018] [Accepted: 04/24/2018] [Indexed: 12/20/2022] Open
Abstract
Vascular endothelial growth factor receptor (VEGFR)-1 exists in different forms, derived from alternative splicing of the same gene. In addition to the transmembrane form, endothelial cells produce a soluble VEGFR-1 (sVEGFR-1) isoform, whereas non-endothelial cells produce both sVEGFR-1 and a different soluble molecule, known as soluble fms-like tyrosine kinase (sFlt)1-14. By binding members of the vascular endothelial growth factor (VEGF) family, the soluble forms reduce the amounts of VEGFs available for the interaction with their transmembrane receptors, thereby negatively regulating VEGFR-mediated signaling. In agreement with this activity, high levels of circulating sVEGFR-1 or sFlt1-14 are associated with different pathological conditions involving vascular dysfunction. Moreover, sVEGFR-1 and sFlt1-14 have an additional role in angiogenesis: they are deposited in the endothelial cell and pericyte extracellular matrix, and interact with cell membrane components. Interaction of sVEGFR-1 with α5β1 integrin on endothelial cell membranes regulates vessel growth, triggering a dynamic, pro-angiogenic phenotype. Interaction of sVEGFR-1/sFlt1-14 with cell membrane glycosphingolipids in lipid rafts controls kidney cell morphology and glomerular barrier functions. These cell⁻matrix contacts represent attractive novel targets for pharmacological intervention in addition to those addressing interactions between VEGFs and their receptors.
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Affiliation(s)
| | - Miriam Carbo
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University, 00185 Rome, Italy.
| | - Veronica Morea
- National Research Council of Italy (CNR), Department of Biochemical Sciences "A. Rossi Fanelli", Institute of Molecular Biology and Pathology c/o, Sapienza University, 00185 Rome, Italy.
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8
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Nordquist E, LaHaye S, Nagel C, Lincoln J. Postnatal and Adult Aortic Heart Valves Have Distinctive Transcriptional Profiles Associated With Valve Tissue Growth and Maintenance Respectively. Front Cardiovasc Med 2018; 5:30. [PMID: 29740591 PMCID: PMC5928323 DOI: 10.3389/fcvm.2018.00030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 03/15/2018] [Indexed: 12/16/2022] Open
Abstract
Heart valves are organized connective tissues of high mechanical demand. They open and close over 100,000 times a day to preserve unidirectional blood flow by maintaining structure-function relationships throughout life. In affected individuals, structural failure compromises function and often leads to regurgitant blood flow and progressive heart failure. This is most common in degenerative valve disease due to age-related wear and tear, or congenital malformations. At present, the only effective treatment of valve disease is surgical repair or replacement and this is often impermanent and requires anti-coagulation therapy throughout life. Therefore, there is a critical need to discover new alternatives. A promising therapeutic area is tissue regeneration and in non-valvular tissues this requires a tightly regulated genetic “growth program” involving cell proliferation. To explore this in heart valves, we performed RNA-seq analysis to compare transcriptional profiles of aortic valve tissue isolated from mice during stages of growth (postnatal day (PND) 2) and adult maintenance (4 months). Data analysis reveals distinct mRNA profiles at each time point and pathway ontology identifies associated changes in biological functions. The PND2 aortic valve is characterized by extensive cell proliferation and expression of mRNAs related to the extracellular matrix (ECM). At 4 months, proliferation is not significant and a differential set of ECM-related genes are expressed. Interestingly there is enrichment of the defense response biological process at this later time point. Together, these data highlight the unique transcriptome of the postnatal valve during stages of growth and maturation, as well as biological functions associated with adult homeostatic valves. These studies create a platform for future work exploring the molecular programs altered in the onset of heart valve disease after birth and provide insights for the development of mechanistic-based therapies.
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Affiliation(s)
- Emily Nordquist
- Molecular Cellular and Developmental Biology Graduate Program, The Ohio State University, Columbus, OH, United States.,Center for Cardiovascular Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,The Heart Center, Nationwide Children's Hospital, Columbus, OH, United States
| | - Stephanie LaHaye
- The Institute for Genomic Medicine at Nationwide Children's Hospital, Columbus, OH, United States
| | - Casey Nagel
- Ocean Ridge Biosciences, Deerfield Beach, FL, United States
| | - Joy Lincoln
- Center for Cardiovascular Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,The Heart Center, Nationwide Children's Hospital, Columbus, OH, United States.,Department of Pediatrics, The Ohio State University, Columbus, OH, United States
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9
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Fong LWR, Yang DC, Chen CH. Myristoylated alanine-rich C kinase substrate (MARCKS): a multirole signaling protein in cancers. Cancer Metastasis Rev 2018; 36:737-747. [PMID: 29039083 DOI: 10.1007/s10555-017-9709-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Emerging evidence implicates myristoylated alanine-rich C-kinase substrate (MARCKS), a major substrate of protein kinase C (PKC), in a critical role for cancer development and progression. MARCKS is tethered to the plasma membrane but can shuttle between the cytosol and plasma membrane via the myristoyl-electrostatic switch. Phosphorylation of MARCKS by PKC leads to its translocation from the plasma membrane to the cytosol where it functions in actin cytoskeletal remodeling, Ca2+ signaling through binding to calmodulin, and regulation of exocytic vesicle release in secretory cells such as neurons and airway goblet cells. Although the contribution of MARCKS to various cellular processes has been extensively studied, its roles in neoplastic disease have been conflicting. This review highlights the molecular and functional differences of MARCKS that exist between normal and tumor cells. We also discuss the recent advances in the potential roles of MARCKS in tumorigenesis, metastasis, and resistance to anti-cancer therapies, with a focus on addressing the inconsistent results regarding the function of MARCKS as a promoter or inhibitor of oncogenesis.
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Affiliation(s)
- Lon Wolf R Fong
- Department of Experimental Therapeutics, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - David C Yang
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, CA, USA.,Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, 95616, USA
| | - Ching-Hsien Chen
- Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, 95616, USA. .,Comprehensive Cancer Center, University of California Davis, Davis, CA, USA.
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10
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Dao CV, Shiraishi M, Miyamoto A. The MARCKS protein amount is differently regulated by calpain during toxic effects of methylmercury between SH-SY5Y and EA.hy926 cells. J Vet Med Sci 2017; 79:1931-1938. [PMID: 29046508 PMCID: PMC5745167 DOI: 10.1292/jvms.17-0473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Methylmercury (MeHg) is an environmental pollutant that shows severe toxicity to humans and animals. However, the molecular mechanisms mediating MeHg toxicity are not completely understood. We have previously reported that the MARCKS protein is involved in the MeHg toxicity to SH-SY5Y neuroblastoma and EA.hy926 vascular endothelial cell lines. In addition, calpain, a Ca2+-dependent protease, is suggested to be associated with the MeHg toxicity. Because MARCKS is known as a substrate of calpain, we studied the relation between calpain activation and cleavage of MARCKS and its role in MeHg toxicity. In SH-SY5Y cells, MeHg decreased cell viability along with increased calcium mobilization, calpain activation and a decrease in MARCKS amounts. However, pretreatment with calpain inhibitors attenuated the decrease in cell viability and MARCKS amount induced only by 1 µM but not by 3 µM MeHg. In cells with a MARCKS knockdown, calpain inhibitors failed to attenuate the decrease in cell viability caused by MeHg. In EA.hy926 cells, although MeHg caused calcium mobilization and a decrease in MARCKS levels, calpain activation was not observed. These results indicate that the participation of calpain in the regulation of MARCKS amounts is dependent on the cell type and concentration of MeHg. In SH-SY5Y cells, calpain-mediated proteolysis of MARCKS is involved in cytotoxicity induced by a low concentration of MeHg.
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Affiliation(s)
- Cuong Van Dao
- Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.,Department of Veterinary Pharmacology, Faculty of Animal Husbandry and Veterinary Medicine, Thai Nguyen University of Agriculture and Forestry, Group 10, Quyet Thang Commune, Thai Nguyen City, Thai Nguyen, Vietnam
| | - Mitsuya Shiraishi
- Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
| | - Atsushi Miyamoto
- Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
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11
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Dorris E, O'Neill A, Hanrahan K, Treacy A, Watson RW. MARCKS promotes invasion and is associated with biochemical recurrence in prostate cancer. Oncotarget 2017; 8:72021-72030. [PMID: 29069765 PMCID: PMC5641108 DOI: 10.18632/oncotarget.18894] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/31/2017] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Overtreatment of low-grade prostate cancer is a recognised problem for clinicians and patients. However, under-treatment runs the risk of missing the opportunity for cure in those who could benefit. Identification of new biomarkers of disease progression, including metastases, is required to better stratify and appropriately treat these patients. The ability to predict if prostate cancer will recur is an important clinical question that would impact treatment options for patients. Studies in other cancers have associated MARCKS with metastasis. METHODS Tissue microarrays of local prostatectomy samples from a cohort of biochemical recurrent and non-biochemical recurrent tumours were assayed for MARCKS protein expression. Prostate cancer cell lines were transfected with siRNA targeting MARCKS or a control and functional endpoints of migration, invasion, proliferation, viability and apoptosis were measured. Actin was visualised by fluorescent microscopy and evidence of a cadherin switch and activation of the AKT pathway were assayed. RESULTS MARCKS was upregulated in biochemical recurrent patients compared to non-biochemical recurrent. Knockdown of MARCKS reduced migration and invasion of prostate cancer cells, reduced MMP9 mRNA expression, as well as decreasing cell spreading and increased cell:cell adhesion in prostate cancer cell colonies. Knockdown of MARCKS had no effect on proliferation, viability or apoptosis of the prostate cancer cells. CONCLUSIONS In conclusion, MARCKS promotes migration and invasion and is associated with biochemical recurrence in localised prostate cancer tumours. The mechanisms by which this occurs have yet to be fully elucidated but lack of a cadherin switch indicates it is not via epithelial-to-mesenchymal transition. Actin rearrangement indicates that MARCKS promotes invasion through regulating the architecture of the cell.
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Affiliation(s)
- Emma Dorris
- UCD School of Medicine, Conway Institute for Biomedical and Biomolecular Sciences, University College Dublin, Belfield, Dublin 4, Ireland
| | - Amanda O'Neill
- UCD School of Medicine, Conway Institute for Biomedical and Biomolecular Sciences, University College Dublin, Belfield, Dublin 4, Ireland
| | - Karen Hanrahan
- UCD School of Medicine, Conway Institute for Biomedical and Biomolecular Sciences, University College Dublin, Belfield, Dublin 4, Ireland
| | - Ann Treacy
- Pathology Department, Mater Private Hospital, Dublin 7, Ireland
| | - R William Watson
- UCD School of Medicine, Conway Institute for Biomedical and Biomolecular Sciences, University College Dublin, Belfield, Dublin 4, Ireland
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12
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Chen CH, Fong LWR, Yu E, Wu R, Trott JF, Weiss RH. Upregulation of MARCKS in kidney cancer and its potential as a therapeutic target. Oncogene 2017; 36:3588-3598. [PMID: 28166200 PMCID: PMC5926797 DOI: 10.1038/onc.2016.510] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 02/07/2023]
Abstract
Targeted therapeutics, such as those abrogating hypoxia inducible factor (HIF)/vascular endothelial growth factor signaling, are initially effective against kidney cancer (or renal cell carcinoma, RCC); however, drug resistance frequently occurs via subsequent activation of alternative pathways. Through genome-scale integrated analysis of the HIF-α network, we identified the major protein kinase C substrate MARCKS (myristoylated alanine-rich C kinase substrate) as a potential target molecule for kidney cancer. In a screen of nephrectomy samples from 56 patients with RCC, we found that MARCKS expression and its phosphorylation are increased and positively correlate with tumor grade. Genetic and pharmacologic suppression of MARCKS in high-grade RCC cell lines in vitro led to a decrease in cell proliferation and migration. We further demonstrated that higher MARCKS expression promotes growth and angiogenesis in vivo in an RCC xenograft tumor. MARCKS acted upstream of the AKT/mTOR pathway, activating HIF-target genes, notably vascular endothelial growth factor-A. Following knockdown of MARCKS in RCC cells, the IC50 of the multikinase inhibitor regorafenib was reduced. Surprisingly, attenuation of MARCKS using the MPS (MARCKS phosphorylation site domain) peptide synergistically interacted with regorafenib treatment and decreased survival of kidney cancer cells through inactivation of AKT and mTOR. Our data suggest a major contribution of MARCKS to kidney cancer growth and provide an alternative therapeutic strategy of improving the efficacy of multikinase inhibitors.
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Affiliation(s)
- C-H Chen
- Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, USA
- Comprehensive Cancer Center, University of California Davis, Davis, CA, USA
| | - LWR Fong
- Department of Immunology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - E Yu
- Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, USA
- Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, Department of Internal Medicine, University of California Davis, Davis, CA, USA
| | - R Wu
- Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, Department of Internal Medicine, University of California Davis, Davis, CA, USA
| | - JF Trott
- Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, USA
| | - RH Weiss
- Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, USA
- Comprehensive Cancer Center, University of California Davis, Davis, CA, USA
- Medical Service, Department of Veterans’ Affairs Northern California Health Care System Center, Sacramento, CA, USA
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13
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Regulation of PI3K by PKC and MARCKS: Single-Molecule Analysis of a Reconstituted Signaling Pathway. Biophys J 2017; 110:1811-1825. [PMID: 27119641 DOI: 10.1016/j.bpj.2016.03.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/09/2016] [Accepted: 03/07/2016] [Indexed: 12/19/2022] Open
Abstract
In chemotaxing ameboid cells, a complex leading-edge signaling circuit forms on the cytoplasmic leaflet of the plasma membrane and directs both actin and membrane remodeling to propel the leading edge up an attractant gradient. This leading-edge circuit includes a putative amplification module in which Ca(2+)-protein kinase C (Ca(2+)-PKC) is hypothesized to phosphorylate myristoylated alanine-rich C kinase substrate (MARCKS) and release phosphatidylinositol-4,5-bisphosphate (PIP2), thereby stimulating production of the signaling lipid phosphatidylinositol-3,4,5-trisphosphate (PIP3) by the lipid kinase phosphoinositide-3-kinase (PI3K). We investigated this hypothesized Ca(2+)-PKC-MARCKS-PIP2-PI3K-PIP3 amplification module and tested its key predictions using single-molecule fluorescence to measure the surface densities and activities of its protein components. Our findings demonstrate that together Ca(2+)-PKC and the PIP2-binding peptide of MARCKS modulate the level of free PIP2, which serves as both a docking target and substrate lipid for PI3K. In the off state of the amplification module, the MARCKS peptide sequesters PIP2 and thereby inhibits PI3K binding to the membrane. In the on state, Ca(2+)-PKC phosphorylation of the MARCKS peptide reverses the PIP2 sequestration, thereby releasing multiple PIP2 molecules that recruit multiple active PI3K molecules to the membrane surface. These findings 1) show that the Ca(2+)-PKC-MARCKS-PIP2-PI3K-PIP3 system functions as an activation module in vitro, 2) reveal the molecular mechanism of activation, 3) are consistent with available in vivo data, and 4) yield additional predictions that are testable in live cells. More broadly, the Ca(2+)-PKC-stimulated release of free PIP2 may well regulate the membrane association of other PIP2-binding proteins, and the findings illustrate the power of single-molecule analysis to elucidate key dynamic and mechanistic features of multiprotein signaling pathways on membrane surfaces.
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14
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VAN Dao C, Islam MZ, Sudo K, Shiraishi M, Miyamoto A. MARCKS is involved in methylmercury-induced decrease in cell viability and nitric oxide production in EA.hy926 cells. J Vet Med Sci 2016; 78:1569-1576. [PMID: 27349763 PMCID: PMC5095626 DOI: 10.1292/jvms.16-0249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Methylmercury (MeHg) is a persistent environmental contaminant that has been reported worldwide. MeHg exposure has been reported to lead to increased risk of cardiovascular diseases; however, the mechanisms underlying the toxic effects of MeHg on the cardiovascular system have not been well elucidated. We have previously reported that mice exposed to MeHg had increased blood pressure along with impaired endothelium-dependent vasodilation. In this study, we investigated the toxic effects of MeHg on a human endothelial cell line, EA.hy926. In addition, we have tried to elucidate the role of myristoylated alanine-rich C kinase substrate (MARCKS) in the MeHg toxicity mechanism in EA.hy926 cells. Cells exposed to MeHg (0.1-10 µM) for 24 hr showed decreased cell viability in a dose-dependent manner. Treatment with submaximal concentrations of MeHg decreased cell migration in the wound healing assay, tube formation on Matrigel and spontaneous nitric oxide (NO) production of EA.hy926 cells. MeHg exposure also elicited a decrease in MARCKS expression and an increase in MARCKS phosphorylation. MARCKS knockdown or MARCKS overexpression in EA.hy926 cells altered not only cell functions, such as migration, tube formation and NO production, but also MeHg-induced decrease in cell viability and NO production. These results suggest the broad role played by MARCKS in endothelial cell functions and the involvement of MARCKS in MeHg-induced toxicity.
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Affiliation(s)
- Cuong VAN Dao
- Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
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15
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Elevated MARCKS phosphorylation contributes to unresponsiveness of breast cancer to paclitaxel treatment. Oncotarget 2016; 6:15194-208. [PMID: 26015406 PMCID: PMC4558145 DOI: 10.18632/oncotarget.3827] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 03/26/2015] [Indexed: 12/12/2022] Open
Abstract
Accumulating evidence has suggested that myristoylated alanine-rich C-kinase substrate (MARCKS) is critical for regulating multiple pathophysiological processes. However, the molecular mechanism underlying increased phosphorylation of MARCKS at Ser159/163 (phospho-MARCKS) and its functional consequence in neoplastic disease remain to be established. Herein, we investigated how phospho-MARCKS is regulated in breast carcinoma, and its role in the context of chemotherapy. In a screen of patients with breast tumors, we find that the abundance of phospho-MARCKS, not MARCKS protein per se, increased in breast cancers and positively correlated with tumor grade and metastatic status. Among chemotherapeutic agents, mitotic inhibitors, including paclitaxel, vincristine or eribulin, notably promoted phospho-MARCKS accumulation in multiple breast cancer cells. We further show that phospho-MARCKS acted upstream of Src activation upon paclitaxel exposure. Reduction of phospho-MARCKS by knockdown of MARCKS or pharmacological agents increased paclitaxel sensitivity. Particularly, a known phospho-MARCKS inhibitor, MANS peptide, was demonstrated to increase paclitaxel efficacy and attenuate angiogenesis/metastasis of xenografted breast cancer cells by decreasing abundance of phospho-MARCKS and messages of inflammatory mediators. Our data suggest that unresponsiveness of breast cancer to paclitaxel treatment is, at least in part, mediated by phospho-MARCKS and also provide an alternative therapeutic strategy against breast cancer by improving taxanes sensitivity.
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16
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In Vitro Neutrophil Migration Requires Protein Kinase C-Delta (δ-PKC)-Mediated Myristoylated Alanine-Rich C-Kinase Substrate (MARCKS) Phosphorylation. Inflammation 2016; 38:1126-41. [PMID: 25515270 DOI: 10.1007/s10753-014-0078-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dysregulated release of neutrophil reactive oxygen species and proteolytic enzymes contributes to both acute and chronic inflammatory diseases. Therefore, molecular regulators of these processes are potential targets for new anti-inflammatory therapies. We have shown previously that myristoylated alanine-rich C-kinase substrate (MARCKS), a well-known actin binding protein and protein kinase C (PKC) substrate, is a key regulator of neutrophil functions. In the current study, we investigate the role of PKC-mediated MARCKS phosphorylation in neutrophil migration and adhesion in vitro. We report that treatment of human neutrophils with the δ-PKC inhibitor rottlerin significantly attenuates f-Met-Leu-Phe (fMLF)-induced MARCKS phosphorylation (IC50=5.709 μM), adhesion (IC50=8.4 μM), and migration (IC50=6.7 μM), while α-, β-, and ζ-PKC inhibitors had no significant effect. We conclude that δ-PKC-mediated MARCKS phosphorylation is essential for human neutrophil migration and adhesion in vitro. These results implicate δ-PKC-mediated MARCKS phosphorylation as a key step in the inflammatory response of neutrophils.
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17
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Synthesis and dephosphorylation of MARCKS in the late stages of megakaryocyte maturation drive proplatelet formation. Blood 2016; 127:1468-80. [PMID: 26744461 DOI: 10.1182/blood-2015-08-663146] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/23/2015] [Indexed: 12/12/2022] Open
Abstract
Platelets are essential for hemostasis, and thrombocytopenia is a major clinical problem. Megakaryocytes (MKs) generate platelets by extending long processes, proplatelets, into sinusoidal blood vessels. However, very little is known about what regulates proplatelet formation. To uncover which proteins were dynamically changing during this process, we compared the proteome and transcriptome of round vs proplatelet-producing MKs by 2D difference gel electrophoresis (DIGE) and polysome profiling, respectively. Our data revealed a significant increase in a poorly-characterized MK protein, myristoylated alanine-rich C-kinase substrate (MARCKS), which was upregulated 3.4- and 5.7-fold in proplatelet-producing MKs in 2D DIGE and polysome profiling analyses, respectively. MARCKS is a protein kinase C (PKC) substrate that binds PIP2. In MKs, it localized to both the plasma and demarcation membranes. MARCKS inhibition by peptide significantly decreased proplatelet formation 53%. To examine the role of MARCKS in the PKC pathway, we treated MKs with polymethacrylate (PMA), which markedly increased MARCKS phosphorylation while significantly inhibiting proplatelet formation 84%, suggesting that MARCKS phosphorylation reduces proplatelet formation. We hypothesized that MARCKS phosphorylation promotes Arp2/3 phosphorylation, which subsequently downregulates proplatelet formation; both MARCKS and Arp2 were dephosphorylated in MKs making proplatelets, and Arp2 inhibition enhanced proplatelet formation. Finally, we used MARCKS knockout (KO) mice to probe the direct role of MARCKS in proplatelet formation; MARCKS KO MKs displayed significantly decreased proplatelet levels. MARCKS expression and signaling in primary MKs is a novel finding. We propose that MARCKS acts as a "molecular switch," binding to and regulating PIP2 signaling to regulate processes like proplatelet extension (microtubule-driven) vs proplatelet branching (Arp2/3 and actin polymerization-driven).
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18
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Kim BR, Lee SH, Park MS, Seo SH, Park YM, Kwon YJ, Rho SB. MARCKSL1 exhibits anti-angiogenic effects through suppression of VEGFR-2-dependent Akt/PDK-1/mTOR phosphorylation. Oncol Rep 2015; 35:1041-8. [PMID: 26555156 DOI: 10.3892/or.2015.4408] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 08/10/2015] [Indexed: 11/06/2022] Open
Abstract
Myristoylated alanine-rich C kinase substrate-like 1 (MARCKSL1) plays a pivotal role in the regulation of apoptosis and has been shown to maintain antitumor and metastasis-suppressive properties. In the present study, we examined the effects of MARCKSL1 as a novel anti-angiogenic agent on the inhibition of angiogenesis-mediated cell migration. MARCKSL1 also reduced vascular endothelial growth factor (VEGF)-induced human umbilical vein endothelial cell (HUVEC) proliferation, as well as capillary-like tubular structure formation in vitro. MARCKSL1 disrupted phosphorylation of vascular endothelial growth factor receptor-2 (VEGFR-2) in ovarian tumorigenesis. In addition, MARCKSL1 showed potent anti-angiogenic activity and reduced the levels of VEGF and hypoxia-inducible factor 1α (HIF-1α) expression, an essential regulator of angiogenesis. Consistently, MARCKSL1 decreased VEGF‑induced phosphorylation of the PI3K/Akt signaling pathway components, including phosphoinositide-dependent protein kinase 1 (PDK-1), mammalian target of rapamycin (mTOR), tuberous sclerosis complex 2 (TSC-2), p70 ribosomal protein S6 kinase (p70S6K), and glycogen synthase kinase 3β (GSK-3β) protein. Collectively, our results provide evidence for the physiological/biological function of an endothelial cell system involved in angiogenesis through suppression of Akt/PDK-1/mTOR phosphorylation by interaction with VEGFR-2.
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Affiliation(s)
- Boh-Ram Kim
- Research Institute, National Cancer Center, Ilsandong-gu, Goyang-si, Gyeonggi-do 410‑769, Republic of Korea
| | - Seung-Hoon Lee
- Department of Life Science, Yong In University, Cheoin-gu, Yongin-si, Gyeonggi‑do 449‑714, Republic of Korea
| | - Mi-Sun Park
- Research Institute, National Cancer Center, Ilsandong-gu, Goyang-si, Gyeonggi-do 410‑769, Republic of Korea
| | - Seung-Hee Seo
- Research Institute, National Cancer Center, Ilsandong-gu, Goyang-si, Gyeonggi-do 410‑769, Republic of Korea
| | - Young-Min Park
- Department of Biological Sciences, Sung Kyun Kwan University, Jangan-gu, Suwon‑si, Gyeonggi‑do 440‑746, Republic of Korea
| | - Young-Joo Kwon
- College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top 5 Program, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Seung-Bae Rho
- Research Institute, National Cancer Center, Ilsandong-gu, Goyang-si, Gyeonggi-do 410‑769, Republic of Korea
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19
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The Effector Domain of MARCKS Is a Nuclear Localization Signal that Regulates Cellular PIP2 Levels and Nuclear PIP2 Localization. PLoS One 2015; 10:e0140870. [PMID: 26470026 PMCID: PMC4607481 DOI: 10.1371/journal.pone.0140870] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 10/01/2015] [Indexed: 01/01/2023] Open
Abstract
Translocation to the nucleus of diacylglycerol kinase (DGK)– ζ is dependent on a sequence homologous to the effector domain of Myristoylated Alanine Rich C-Kinase Substrate (MARCKS). These data would suggest that MARCKS could also localize to the nucleus. A single report demonstrated immunofluorescence staining of MARCKS in the nucleus; however, further experimental evidence confirming the specific domain responsible for this localization has not been reported. Here, we report that MARCKS is present in the nucleus in GBM cell lines. We then over-expressed wild-type MARCKS (WT) and MARCKS with the effector domain deleted (ΔED), both tagged with V5-epitope in a GBM cell line with low endogenous MARCKS expression (U87). We found that MARCKS-WT localized to the nucleus, while the MARCKS construct without the effector domain remained in the cytoplasm. We also found that over-expression of MARCKS-WT resulted in a significant increase in total cellular phosphatidyl-inositol (4,5) bisphosphate (PIP2) levels, consistent with prior evidence that MARCKS can regulate PIP2 levels. We also found increased staining for PIP2 in the nucleus with MARCKS-WT over-expression compared to MARCKS ΔED by immunofluorescence. Interestingly, we observed MARCKS and PIP2 co-localization in the nucleus. Lastly, we found changes in gene expression when MARCKS was not present in the nucleus (MARCKS ΔED). These data indicate that the MARCKS effector domain can function as a nuclear localization signal and that this sequence is critical for the ability of MARCKS to regulate PIP2 levels, nuclear localization, and gene expression. These data suggests a novel role for MARCKS in regulating nuclear functions such as gene expression.
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Frazer S, Otomo K, Dayer A. Early-life serotonin dysregulation affects the migration and positioning of cortical interneuron subtypes. Transl Psychiatry 2015; 5:e644. [PMID: 26393490 PMCID: PMC5068808 DOI: 10.1038/tp.2015.147] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 07/22/2015] [Accepted: 08/11/2015] [Indexed: 12/21/2022] Open
Abstract
Early-life deficiency of the serotonin transporter (SERT) gives rise to a wide range of psychiatric-relevant phenotypes; however, the molecular and cellular targets of serotonin dyregulation during neural circuit formation remain to be identified. Interestingly, migrating cortical interneurons (INs) derived from the caudal ganglionic eminence (CGE) have been shown to be more responsive to serotonin-mediated signalling compared with INs derived from the medial ganglionic eminence (MGE). Here we investigated the impact of early-life SERT deficiency on the migration and positioning of CGE-derived cortical INs in SERT-ko mice and in mice exposed to the SERT inhibitor fluoxetine during the late embryonic period. Using confocal time-lapse imaging and microarray-based expression analysis we found that genetic and pharmacological SERT deficiency significantly increased the migratory speed of CGE-derived INs and affected transcriptional programmes regulating neuronal migration. Postnatal studies revealed that SERT deficiency altered the cortical laminar distribution of subtypes of CGE-derived INs but not MGE-derived INs. More specifically, we found that the distribution of vasointestinal peptide (VIP)-expressing INs in layer 2/3 was abnormal in both genetic and pharmacological SERT-deficiency models. Collectively, these data indicate that early-life SERT deficiency has an impact on the migration and molecular programmes of CGE-derived INs, thus leading to specific alterations in the positioning of VIP-expressing INs. These data add to the growing evidence that early-life serotonin dysregulation affects cortical microcircuit formation and contributes to the emergence of psychiatric-relevant phenotypes.
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Affiliation(s)
- S Frazer
- Department of Mental Health and Psychiatry, University of Geneva Medical School, Geneva, Switzerland,Department of Psychiatry and Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland
| | - K Otomo
- Department of Mental Health and Psychiatry, University of Geneva Medical School, Geneva, Switzerland,Department of Psychiatry and Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland
| | - A Dayer
- Department of Mental Health and Psychiatry, University of Geneva Medical School, Geneva, Switzerland,Department of Psychiatry and Basic Neurosciences, University of Geneva Medical School, Geneva, Switzerland,Department of Psychiatry and Basic Neurosciences, University of Geneva Medical School (CMU), Rue Michel-Servet 1, 1211 Genève 4, Geneva 1211, Switzerland. E-mail:
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Tsutsui T, Fukasawa R, Tanaka A, Hirose Y, Ohkuma Y. Identification of target genes for the CDK subunits of the Mediator complex. Genes Cells 2015; 16:1208-18. [PMID: 22117896 DOI: 10.1111/j.1365-2443.2011.01565.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mediator is a large complex containing up to 30 subunits that consist of four modules each: head, middle, tail and CDK/Cyclin. Recent studies have shown that CDK8, a subunit of the CDK/Cyclin module, is one of the key subunits of Mediator that mediates its pivotal roles in transcriptional regulation. In addition to CDK8, CDK19 was identified in human Mediator with a great deal of similarity to CDK8 but was conserved only in vertebrates. Previously, we reported that human CDK19 could form the Mediator complexes independent of CDK8. To further investigate the in vivo transcriptional activities of the complexes, we used a luciferase assay in combined with siRNA-mediated knockdown to show that CDK8 and CDK19 possess opposing functions in viral activator VP16-dependent transcriptional regulation. CDK8 supported transcriptional activation, whereas CDK19, however, counteracted it. In this study, we further characterized CDK19. We used microarrays to identify target genes for each CDK, and we selected six genes: two target genes of CDK8, two target genes of CDK19 and two genes that were targets for both. Surprisingly, it turned out that both CDKs bound to all six target genes, regardless of their effects in transcription upon binding, suggesting Mediator as a context-specific transcriptional regulator.
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Affiliation(s)
- Taiki Tsutsui
- Laboratory of Gene Regulation, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
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Marinković G, Heemskerk N, van Buul JD, de Waard V. The Ins and Outs of Small GTPase Rac1 in the Vasculature. J Pharmacol Exp Ther 2015; 354:91-102. [PMID: 26036474 DOI: 10.1124/jpet.115.223610] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/01/2015] [Indexed: 12/16/2022] Open
Abstract
The Rho family of small GTPases forms a 20-member family within the Ras superfamily of GTP-dependent enzymes that are activated by a variety of extracellular signals. The most well known Rho family members are RhoA (Ras homolog gene family, member A), Cdc42 (cell division control protein 42), and Rac1 (Ras-related C3 botulinum toxin substrate 1), which affect intracellular signaling pathways that regulate a plethora of critical cellular functions, such as oxidative stress, cellular contacts, migration, and proliferation. In this review, we describe the current knowledge on the role of GTPase Rac1 in the vasculature. Whereas most recent reviews focus on the role of vascular Rac1 in endothelial cells, in the present review we also highlight the functional involvement of Rac1 in other vascular cells types, namely, smooth muscle cells present in the media and fibroblasts located in the adventitia of the vessel wall. Collectively, this overview shows that Rac1 activity is involved in various functions within one cell type at distinct locations within the cell, and that there are overlapping but also cell type-specific functions in the vasculature. Chronically enhanced Rac1 activity seems to contribute to vascular pathology; however, Rac1 is essential to vascular homeostasis, which makes Rac1 inhibition as a therapeutic option a delicate balancing act.
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Affiliation(s)
- Goran Marinković
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Niels Heemskerk
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jaap D van Buul
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Vivian de Waard
- Department Medical Biochemistry (G.M., V.d.W.) and Department of Molecular Cell Biology (N.H., J.D.v.B.), Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Choi S, Thapa N, Tan X, Hedman AC, Anderson RA. PIP kinases define PI4,5P₂signaling specificity by association with effectors. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1851:711-23. [PMID: 25617736 PMCID: PMC4380618 DOI: 10.1016/j.bbalip.2015.01.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 01/14/2015] [Accepted: 01/16/2015] [Indexed: 12/21/2022]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI4,5P₂) is an essential lipid messenger with roles in all eukaryotes and most aspects of human physiology. By controlling the targeting and activity of its effectors, PI4,5P₂modulates processes, such as cell migration, vesicular trafficking, cellular morphogenesis, signaling and gene expression. In cells, PI4,5P₂has a much higher concentration than other phosphoinositide species and its total content is largely unchanged in response to extracellular stimuli. The discovery of a vast array of PI4,5P₂ binding proteins is consistent with data showing that the majority of cellular PI4,5P₂is sequestered. This supports a mechanism where PI4,5P₂functions as a localized and highly specific messenger. Further support of this mechanism comes from the de novo synthesis of PI4,5P₂which is often linked with PIP kinase interaction with PI4,5P₂effectors and is a mechanism to define specificity of PI4,5P₂signaling. The association of PI4,5P₂-generating enzymes with PI4,5P₂effectors regulate effector function both temporally and spatially in cells. In this review, the PI4,5P₂effectors whose functions are tightly regulated by associations with PI4,5P₂-generating enzymes will be discussed. This article is part of a Special Issue entitled Phosphoinositides.
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Affiliation(s)
- Suyong Choi
- Cellular and Molecular Biology Program, University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Narendra Thapa
- Molecular and Cellular Pharmacology Program, University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Xiaojun Tan
- Molecular and Cellular Pharmacology Program, University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Andrew C Hedman
- Molecular and Cellular Pharmacology Program, University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA
| | - Richard A Anderson
- Cellular and Molecular Biology Program, University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA; Molecular and Cellular Pharmacology Program, University of Wisconsin-Madison, School of Medicine and Public Health, 1300 University Avenue, Madison, WI 53706, USA.
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Chen CH, Statt S, Chiu CL, Thai P, Arif M, Adler KB, Wu R. Targeting myristoylated alanine-rich C kinase substrate phosphorylation site domain in lung cancer. Mechanisms and therapeutic implications. Am J Respir Crit Care Med 2015; 190:1127-38. [PMID: 25318062 DOI: 10.1164/rccm.201408-1505oc] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
RATIONALE Phosphorylation of myristoylated alanine-rich C kinase substrate (phospho-MARCKS) at the phosphorylation site domain (PSD) is crucial for mucus granule secretion and cell motility, but little is known concerning its function in lung cancer. OBJECTIVES We aimed to determine if MARCKS PSD activity can serve as a therapeutic target and to elucidate the molecular basis of this potential. METHODS The clinical relevance of phospho-MARCKS was first confirmed. Next, we used genetic approaches to verify the functionality and molecular mechanism of phospho-MARCKS. Finally, cancer cells were pharmacologically inhibited for MARCKS activity and subjected to functional bioassays. MEASUREMENTS AND MAIN RESULTS We demonstrated that higher phospho-MARCKS levels were correlated with shorter overall survival of lung cancer patients. Using shRNA silencing and ectopic expression of wild-type and PSD-mutated (S159/163A) MARCKS, we showed that elevated phospho-MARCKS promoted cancer growth and erlotinib resistance. Further studies demonstrated an interaction of phosphoinositide 3-kinase with MARCKS, but not with phospho-MARCKS. Interestingly, phospho-MARCKS acted in parallel with increased phosphatidylinositol (3,4,5)-triphosphate pools and AKT activation in cells. Through treatment with a 25-mer peptide targeting the MARCKS PSD motif (MPS peptide), we were able to suppress tumor growth and metastasis in vivo, and reduced levels of phospho-MARCKS, phosphatidylinositol (3,4,5)-triphosphate, and AKT activity. This peptide also enhanced the sensitivity of lung cancer cells to erlotinib treatment, especially those with sustained activation of phosphoinositide 3-kinase/AKT signaling. CONCLUSIONS These results suggest a key role for MARCKS PSD in cancer disease and provide a unique strategy for inhibiting the activity of MARCKS PSD as a treatment for lung cancer.
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Affiliation(s)
- Ching-Hsien Chen
- 1 Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, California; and
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Rohrbach TD, Jarboe JS, Anderson JC, Trummell HQ, Hicks PH, Weaver AN, Yang ES, Oster RA, Deshane JS, Steele C, Siegal GP, Bonner JA, Willey CD. Targeting the effector domain of the myristoylated alanine rich C-kinase substrate enhances lung cancer radiation sensitivity. Int J Oncol 2014; 46:1079-88. [PMID: 25524703 DOI: 10.3892/ijo.2014.2799] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 11/07/2014] [Indexed: 11/06/2022] Open
Abstract
Lung cancer is the leading cause of cancer related deaths. Common molecular drivers of lung cancer are mutations in receptor tyrosine kinases (RTKs) leading to activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pro-growth, pro-survival signaling pathways. Myristoylated alanine rich C-kinase substrate (MARCKS) is a protein that has the ability to mitigate this signaling cascade by sequestering the target of PI3K, phosphatidylinositol (4,5)-bisphosphate (PIP2). As such, MARCKS has been implicated as a tumor suppressor, though there is some evidence that MARCKS may be tumor promoting in certain cancer types. Since the MARCKS function depends on its phosphorylation status, which impacts its subcellular location, MARCKS role in cancer may depend highly on the signaling context. Currently, the importance of MARCKS in lung cancer biology is limited. Thus, we investigated MARCKS in both clinical specimens and cell culture models. Immunohistochemistry scoring of MARCKS protein expression in a diverse lung tumor tissue array revealed that the majority of squamous cell carcinomas stained positive for MARCKS while other histologies, such as adenocarcinomas, had lower levels. To study the importance of MARCKS in lung cancer biology, we used inducible overexpression of wild-type (WT) and non-phosphorylatable (NP)-MARCKS in A549 lung cancer cells that had a low level of endogenous MARCKS. We found that NP-MARCKS expression, but not WT-MARCKS, enhanced the radiosensitivity of A549 cells in part by inhibiting DNA repair as evidenced by prolonged radiation-induced DNA double strand breaks. We confirmed the importance of MARCKS phosphorylation status by treating several lung cancer cell lines with a peptide mimetic of the phosphorylation domain, the effector domain (ED), which effectively attenuated cell growth as measured by cell index. Thus, the MARCKS ED appears to be an important target for lung cancer therapeutic development.
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Affiliation(s)
- Timothy D Rohrbach
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - John S Jarboe
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joshua C Anderson
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hoa Q Trummell
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Patricia H Hicks
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Alice N Weaver
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Eddy S Yang
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Robert A Oster
- Division of Preventive Medicine, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jessy S Deshane
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Chad Steele
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Gene P Siegal
- Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - James A Bonner
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Christopher D Willey
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, AL, USA
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Wang SJH, Tsai A, Wang M, Yoo S, Kim HY, Yoo B, Chui V, Kisiel M, Stewart B, Parkhouse W, Harden N, Krieger C. Phospho-regulated Drosophila adducin is a determinant of synaptic plasticity in a complex with Dlg and PIP2 at the larval neuromuscular junction. Biol Open 2014; 3:1196-206. [PMID: 25416060 PMCID: PMC4265757 DOI: 10.1242/bio.20148342] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Accepted: 10/15/2014] [Indexed: 12/12/2022] Open
Abstract
Adducin is a ubiquitously expressed actin- and spectrin-binding protein involved in cytoskeleton organization, and is regulated through phosphorylation of the myristoylated alanine-rich C-terminal kinase (MARCKS)-homology domain by protein kinase C (PKC). We have previously shown that the Drosophila adducin, Hu-li tai shao (Hts), plays a role in larval neuromuscular junction (NMJ) growth. Here, we find that the predominant isoforms of Hts at the NMJ contain the MARCKS-homology domain, which is important for interactions with Discs large (Dlg) and phosphatidylinositol 4,5-bisphosphate (PIP2). Through the use of Proximity Ligation Assay (PLA), we show that the adducin-like Hts isoforms are in complexes with Dlg and PIP2 at the NMJ. We provide evidence that Hts promotes the phosphorylation and delocalization of Dlg at the NMJ through regulation of the transcript distribution of the PAR-1 and CaMKII kinases in the muscle. We also show that Hts interactions with Dlg and PIP2 are impeded through phosphorylation of the MARCKS-homology domain. These results are further evidence that Hts is a signaling-responsive regulator of synaptic plasticity in Drosophila.
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Affiliation(s)
- Simon Ji Hau Wang
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Amy Tsai
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Mannan Wang
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - SooHyun Yoo
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Hae-Yoon Kim
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Byoungjoo Yoo
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Vincent Chui
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Marta Kisiel
- Department of Biology, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
| | - Bryan Stewart
- Department of Biology, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
| | - Wade Parkhouse
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Nicholas Harden
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
| | - Charles Krieger
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada
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Trovò L, Stroobants S, D'Hooge R, Ledesma MD, Dotti CG. Improvement of biochemical and behavioral defects in the Niemann-Pick type A mouse by intraventricular infusion of MARCKS. Neurobiol Dis 2014; 73:319-26. [PMID: 25251606 DOI: 10.1016/j.nbd.2014.09.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 07/31/2014] [Accepted: 09/12/2014] [Indexed: 12/28/2022] Open
Abstract
Niemann-Pick disease type A (NPDA) is a fatal disease due to mutations in the acid sphingomyelinase (ASM) gene, which triggers the abnormal accumulation of sphingomyelin (SM) in lysosomes and the plasma membrane of mutant cells. Although the disease affects multiple organs, the impact on the brain is the most invalidating feature. The mechanisms responsible for the cognitive deficit characteristic of this condition are only partially understood. Using mice lacking the ASM gene (ASMko), a model system in NPDA research, we report here that high sphingomyelin levels in mutant neurons lead to low synaptic levels of phosphoinositide PI(4,5)P2 and reduced activity of its hydrolyzing phosphatase PLCγ, which are key players in synaptic plasticity events. In addition, mutant neurons have reduced levels of membrane-bound MARCKS, a protein required for PI(4,5)P2 membrane clustering and hydrolysis. Intracerebroventricular infusion of a peptide that mimics the effector domain of MARCKS increases the content of PI(4,5)P2 in the synaptic membrane and ameliorates behavioral abnormalities in ASMko mice.
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Affiliation(s)
- Laura Trovò
- Center for Human Genetics, VIB Center for the Biology of Disease and Katholieke Universiteit Leuven, Herestraat 49, 3000 Leuven, Belgium.
| | - Stijn Stroobants
- Laboratory of Biological Psychology, Faculty of Psychology and Educational Sciences, University of Leuven (K.U. Leuven), Belgium
| | - Rudi D'Hooge
- Laboratory of Biological Psychology, Faculty of Psychology and Educational Sciences, University of Leuven (K.U. Leuven), Belgium
| | - Maria Dolores Ledesma
- Centro Biología Molecular "Severo Ochoa" (CSIC-UAM), Campus Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Carlos G Dotti
- Centro Biología Molecular "Severo Ochoa" (CSIC-UAM), Campus Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain.
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Zhou Y, Hancock JF. Ras nanoclusters: Versatile lipid-based signaling platforms. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:841-9. [PMID: 25234412 DOI: 10.1016/j.bbamcr.2014.09.008] [Citation(s) in RCA: 175] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 09/05/2014] [Accepted: 09/08/2014] [Indexed: 12/31/2022]
Abstract
Ras proteins assemble into transient nanoclusters on the plasma membrane. Nanoclusters are the sites of Ras effector recruitment and activation and are therefore essential for signal transmission. The dynamics of nanocluster formation and disassembly result in interesting emergent properties including high-fidelity signal transmission. More recently the lipid structure of Ras nanoclusters has been reported and shown to contribute to isoform-specific Ras signaling. In addition specific lipids play critical roles in mediating the formation, stability and dynamics of Ras nanoclusters. In consequence the spatiotemporal organization of these lipids has emerged as important and novel regulators of Ras function. This article is part of a Special Issue entitled: Nanoscale membrane organisation and signalling.
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Affiliation(s)
- Yong Zhou
- Department of Integrative Biology and Pharmacology, University of Texas Medical School, Houston, TX 77030, USA.
| | - John F Hancock
- Department of Integrative Biology and Pharmacology, University of Texas Medical School, Houston, TX 77030, USA.
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Kim BR, Dong SM, Seo SH, Lee JH, Lee JM, Lee SH, Rho SB. Lysyl oxidase-like 2 (LOXL2) controls tumor-associated cell proliferation through the interaction with MARCKSL1. Cell Signal 2014; 26:1765-73. [DOI: 10.1016/j.cellsig.2014.05.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 05/15/2014] [Indexed: 01/25/2023]
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Central role for hydrogen peroxide in P2Y1 ADP receptor-mediated cellular responses in vascular endothelium. Proc Natl Acad Sci U S A 2014; 111:3383-8. [PMID: 24550450 DOI: 10.1073/pnas.1320854111] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ADP activates a family of cell surface receptors that modulate signaling pathways in a broad range of cells. ADP receptor antagonists are widely used to treat cardiovascular disease states. These studies identify a critical role for the stable reactive oxygen species hydrogen peroxide (H2O2) in mediating cellular responses activated by the G protein-coupled P2Y1 receptor for ADP. We found that ADP-dependent phosphorylation of key endothelial signaling proteins--including endothelial nitric oxide synthase, AMP-activated protein kinase, and the actin-binding MARCKS protein--was blocked by preincubation with PEG-catalase, which degrades H2O2. ADP treatment promoted the H2O2-dependent phosphorylation of c-Abl, a nonreceptor tyrosine kinase that modulates the actin cytoskeleton. Cellular imaging experiments using fluorescence resonance energy transfer-based biosensors revealed that ADP-stimulated activation of the cytoskeleton-associated small GTPase Rac1 was independent of H2O2. However, Rac1-dependent activation of AMP-activated protein kinase, the signaling phospholipid phosphatidylinositol-(4, 5)-bisphosphate, and the c-Abl-interacting protein CrkII are mediated by H2O2. We transfected endothelial cells with differentially targeted HyPer2 H2O2 biosensors and found that ADP promoted a marked increase in H2O2 levels in the cytosol and caveolae, and a smaller increase in mitochondria. We performed a screen for P2Y1 receptor-mediated receptor tyrosine kinase transactivation and discovered that ADP transactivates Fms-like tyrosine kinase 3 (Flt3), a receptor tyrosine kinase expressed in these cells. Our observation that P2Y1 receptor-mediated responses involve Flt3 transactivation may identify a unique mechanism whereby cancer chemotherapy with receptor tyrosine kinase inhibitors promotes vascular dysfunction. Taken together, these findings establish a critical role for endogenous H2O2 in control of ADP-mediated signaling responses in the vascular wall.
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Alonso S, Bär M. Modeling domain formation of MARCKS and protein kinase C at cellular membranes. ACTA ACUST UNITED AC 2014. [DOI: 10.1140/epjnbp14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Signal integration by lipid-mediated spatial cross talk between Ras nanoclusters. Mol Cell Biol 2013; 34:862-76. [PMID: 24366544 DOI: 10.1128/mcb.01227-13] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipid-anchored Ras GTPases form transient, spatially segregated nanoclusters on the plasma membrane that are essential for high-fidelity signal transmission. The lipid composition of Ras nanoclusters, however, has not previously been investigated. High-resolution spatial mapping shows that different Ras nanoclusters have distinct lipid compositions, indicating that Ras proteins engage in isoform-selective lipid sorting and accounting for different signal outputs from different Ras isoforms. Phosphatidylserine is a common constituent of all Ras nanoclusters but is only an obligate structural component of K-Ras nanoclusters. Segregation of K-Ras and H-Ras into spatially and compositionally distinct lipid assemblies is exquisitely sensitive to plasma membrane phosphatidylserine levels. Phosphatidylserine spatial organization is also modified by Ras nanocluster formation. In consequence, Ras nanoclusters engage in remote lipid-mediated communication, whereby activated H-Ras disrupts the assembly and operation of spatially segregated K-Ras nanoclusters. Computational modeling and experimentation reveal that complex effects of caveolin and cortical actin on Ras nanoclustering are similarly mediated through regulation of phosphatidylserine spatiotemporal dynamics. We conclude that phosphatidylserine maintains the lateral segregation of diverse lipid-based assemblies on the plasma membrane and that lateral connectivity between spatially remote lipid assemblies offers important previously unexplored opportunities for signal integration and signal processing.
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Orecchia A, Mettouchi A, Uva P, Simon GC, Arcelli D, Avitabile S, Ragone G, Meneguzzi G, Pfenninger KH, Zambruno G, Failla CM. Endothelial cell adhesion to soluble vascular endothelial growth factor receptor‐1 triggers a cell dynamic and angiogenic phenotype. FASEB J 2013; 28:692-704. [DOI: 10.1096/fj.12-225771] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Angela Orecchia
- Molecular and Cell Biology LaboratoryIstituto Dermopatico dell'Immacolata (IDI)–Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS)RomeItaly
| | - Amel Mettouchi
- Institut National de la Santé et de la Recherche Médicale (INSERM) U634NiceFrance
| | - Paolo Uva
- Center for Advanced Studies, Research, and Development in Sardinia (CRS4)Bioinformatics LaboratoryCagliariItaly
| | - Glenn C. Simon
- Department of PediatricsUniversity of ColoradoAuroraColoradoUSA
| | - Diego Arcelli
- Molecular Oncology LaboratoryIstituto Dermopatico dell'Immacolata (IDI)–Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS)RomeItaly
| | - Simona Avitabile
- Molecular and Cell Biology LaboratoryIstituto Dermopatico dell'Immacolata (IDI)–Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS)RomeItaly
| | - Gianluca Ragone
- Molecular Oncology LaboratoryIstituto Dermopatico dell'Immacolata (IDI)–Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS)RomeItaly
| | - Guerrino Meneguzzi
- Institut National de la Santé et de la Recherche Médicale (INSERM) U634NiceFrance
| | | | - Giovanna Zambruno
- Molecular and Cell Biology LaboratoryIstituto Dermopatico dell'Immacolata (IDI)–Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS)RomeItaly
| | - Cristina Maria Failla
- Molecular and Cell Biology LaboratoryIstituto Dermopatico dell'Immacolata (IDI)–Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS)RomeItaly
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Browne BC, Hochgräfe F, Wu J, Millar EKA, Barraclough J, Stone A, McCloy RA, Lee CS, Roberts C, Ali NA, Boulghourjian A, Schmich F, Linding R, Farrow L, Gee JMW, Nicholson RI, O'Toole SA, Sutherland RL, Musgrove EA, Butt AJ, Daly RJ. Global characterization of signalling networks associated with tamoxifen resistance in breast cancer. FEBS J 2013; 280:5237-57. [PMID: 23876235 DOI: 10.1111/febs.12441] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 06/27/2013] [Accepted: 07/17/2013] [Indexed: 12/30/2022]
Abstract
Acquired resistance to the anti-estrogen tamoxifen remains a significant challenge in breast cancer management. In this study, we used an integrative approach to characterize global protein expression and tyrosine phosphorylation events in tamoxifen-resistant MCF7 breast cancer cells (TamR) compared with parental controls. Quantitative mass spectrometry and computational approaches were combined to identify perturbed signalling networks, and candidate regulatory proteins were functionally interrogated by siRNA-mediated knockdown. Network analysis revealed that cellular metabolism was perturbed in TamR cells, together with pathways enriched for proteins associated with growth factor, cell-cell and cell matrix-initiated signalling. Consistent with known roles for Ras/MAPK and PI3-kinase signalling in tamoxifen resistance, tyrosine-phosphorylated MAPK1, SHC1 and PIK3R2 were elevated in TamR cells. Phosphorylation of the tyrosine kinase Yes and expression of the actin-binding protein myristoylated alanine-rich C-kinase substrate (MARCKS) were increased two- and eightfold in TamR cells respectively, and these proteins were selected for further analysis. Knockdown of either protein in TamR cells had no effect on anti-estrogen sensitivity, but significantly decreased cell motility. MARCKS expression was significantly higher in breast cancer cell lines than normal mammary epithelial cells and in ER-negative versus ER-positive breast cancer cell lines. In primary breast cancers, cytoplasmic MARCKS staining was significantly higher in basal-like and HER2 cancers than in luminal cancers, and was independently predictive of poor survival in multivariate analyses of the whole cohort (P < 0.0001) and in ER-positive patients (P = 0.0005). These findings provide network-level insights into the molecular alterations associated with the tamoxifen-resistant phenotype, and identify MARCKS as a potential biomarker of therapeutic responsiveness that may assist in stratification of patients for optimal therapy.
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Affiliation(s)
- Brigid C Browne
- Cancer Research Program, The Kinghorn Cancer Centre, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
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35
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Chen CH, Thai P, Yoneda K, Adler KB, Yang PC, Wu R. A peptide that inhibits function of Myristoylated Alanine-Rich C Kinase Substrate (MARCKS) reduces lung cancer metastasis. Oncogene 2013; 33:3696-706. [PMID: 23955080 DOI: 10.1038/onc.2013.336] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 07/04/2013] [Accepted: 07/07/2013] [Indexed: 12/25/2022]
Abstract
Myristoylated Alanine-Rich C Kinase Substrate (MARCKS), a substrate of protein kinase C, is a key regulatory molecule controlling mucus granule secretion by airway epithelial cells as well as directed migration of leukocytes, stem cells and fibroblasts. Phosphorylation of MARKCS may be involved in these responses. However, the functionality of MARCKS and its related phosphorylation in lung cancer malignancy have not been characterized. This study demonstrated elevated levels of MARCKS and phospho-MARCKS in highly invasive lung cancer cell lines and lung cancer specimens from non-small-cell lung cancer patients. siRNA knockdown of MARCKS expression in these highly invasive lung cancer cell lines reduced cell migration and suppressed PI3K (phosphatidylinositol 3'-kinase)/Akt phosphorylation and Slug level. Interestingly, treatment with a peptide identical to the MARCKS N-terminus sequence (the MANS peptide) impaired cell migration in vitro and also the metastatic potential of invasive lung cancer cells in vivo. Mechanistically, MANS peptide treatment resulted in a coordination of increase of E-cadherin expression, suppression of MARCKS phosphorylation and AKT/Slug signalling pathway but not the expression of total MARCKS. These results indicate a crucial role for MARCKS, specifically its phosphorylated form, in potentiating lung cancer cell migration/metastasis and suggest a potential use of MARCKS-related peptides in the treatment of lung cancer metastasis.
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Affiliation(s)
- C-H Chen
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, CA, USA
| | - P Thai
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, CA, USA
| | - K Yoneda
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, CA, USA
| | - K B Adler
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, NC, USA
| | - P-C Yang
- Department of Internal Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - R Wu
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, CA, USA
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36
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Kim WK, Park M, Park M, Kim YJ, Shin N, Kim HK, You KT, Kim H. Identification and Selective Degradation of Neopeptide-Containing Truncated Mutant Proteins in the Tumors with High Microsatellite Instability. Clin Cancer Res 2013; 19:3369-82. [DOI: 10.1158/1078-0432.ccr-13-0684] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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37
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Trovò L, Ahmed T, Callaerts-Vegh Z, Buzzi A, Bagni C, Chuah M, Vandendriessche T, D'Hooge R, Balschun D, Dotti CG. Low hippocampal PI(4,5)P₂ contributes to reduced cognition in old mice as a result of loss of MARCKS. Nat Neurosci 2013; 16:449-55. [PMID: 23434911 DOI: 10.1038/nn.3342] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 01/18/2013] [Indexed: 02/03/2023]
Abstract
Cognitive and motor performances decline during aging. Although it is clear that such signs reflect synaptic compromise, the underlying mechanisms have not been defined. We found that the levels and activity of the synaptic plasticity modulators phosphatidylinositol-(4,5)-bisphosphate (PI(4,5)P₂) and phospholipase Cγ (PLCγ) were substantially reduced in hippocampal synaptic membranes from old mice. In addition, these membranes contained reduced levels of the PI(4,5)P₂-clustering molecule myristoylated alanine-rich C kinase substrate (MARCKS). Consistent with a cause-effect relationship, raising MARCKS levels in the brain of old mice led to increased synaptic membrane clustering of PI(4,5)P₂ and to PLCγ activation. MARCKS overexpression in the hippocampus of old mice or intraventricular perfusion of MARCKS peptide resulted in enhanced long-term potentiation and improved memory. These results reveal one of the mechanisms involved in brain dysfunction during aging.
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Affiliation(s)
- Laura Trovò
- VIB Center for the Biology of Disease, Leuven and Center for Human Genetics, University of Leuven (Katholieke University of Leuven), Leuven, Belgium
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38
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Sheehan AJ, Goodrich W, Banks P, Crouch MF, Osmond RIW. Development and validation of a single-well cell-based assay for the detection of endogenous phosphoproteins. Assay Drug Dev Technol 2012; 11:108-16. [PMID: 23062078 DOI: 10.1089/adt.2012.471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We describe a cellular assay for detection of phosphorylation of endogenous proteins, whereby cells are seeded, treated, and assayed for modulation of phosphorylation in a single microplate well. The procedure is coupled to a rapid, one-wash sandwich enzyme-linked immuno-sorbent assay, enabling results to be obtained within 3-4 h from cell seeding. The assay was tested in two separate cellular systems, namely, HeLa and MCF-7 cells. When using the one-well protocol with Akt phosphorylation as a model, the response to a number of agonists was the same as the response obtained using cells treated in a separate microplate, using a conventional lysate transfer approach. The assay procedure was automated, and quantitative pharmacological data on three known inhibitors of the PI3-kinase signaling pathway was obtained within 4 h from seeding cells, with six dispense steps, and a single wash cycle. Thus, the protocol affords a reliable means of assaying for cellular signaling events in different cell types, and is amenable to automation.
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MARCKS protein mediates hydrogen peroxide regulation of endothelial permeability. Proc Natl Acad Sci U S A 2012; 109:14864-9. [PMID: 22927426 DOI: 10.1073/pnas.1204974109] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Impairment of endothelial barrier function is implicated in many vascular and inflammatory disorders. One prevalent mechanism of endothelial dysfunction is an increase in reactive oxygen species under oxidative stress. Previous reports have demonstrated that hydrogen peroxide (H(2)O(2)), a highly stable reactive oxygen species that modulates physiological signaling pathways, also enhances endothelial permeability, but the mechanism of this effect is unknown. Here, we identify the actin-binding protein myristoylated alanine-rich C-kinase substrate (MARCKS) as a key mediator of the H(2)O(2)-induced permeability change in bovine aortic endothelial cells. MARCKS knockdown and H(2)O(2) treatment alter the architecture of the actin cytoskeleton in endothelial cells, and H(2)O(2) induces the phosphorylation and translocation of MARCKS from the cell membrane to the cytosol. Using pharmacological inhibitors and small interference RNA constructs directed against specific proteins, we uncover a signaling cascade from Rac1 to Abl1, phospholipase Cγ1, and PKCδ that is triggered by H(2)O(2) and leads to MARCKS phosphorylation. Our findings establish a distinct role for MARCKS in the regulation of H(2)O(2)-induced permeability change in endothelial cells, and suggest potential new therapeutic targets for the treatment of disorders involving oxidative stress and altered endothelial permeability.
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Kalwa H, Sartoretto JL, Sartoretto SM, Michel T. Angiotensin-II and MARCKS: a hydrogen peroxide- and RAC1-dependent signaling pathway in vascular endothelium. J Biol Chem 2012; 287:29147-58. [PMID: 22773836 DOI: 10.1074/jbc.m112.381517] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
MARCKS is an actin-binding protein that modulates vascular endothelial cell migration and cytoskeleton signaling (Kalwa, H., and Michel, T. (2011) J. Biol. Chem. 286, 2320-2330). Angiotensin-II is a vasoactive peptide implicated in vascular physiology as well as pathophysiology; the pathways connecting angiotensin-II and cytoskeletal remodeling are incompletely understood. Here we show that MARCKS is expressed in intact arterial preparations, with prominent staining of the endothelium. In endothelial cells, angiotensin-II-promoted MARCKS phosphorylation is abrogated by PEG-catalase, implicating endogenous H(2)O(2) in the angiotensin-II response. Studies using the H(2)O(2) biosensor HyPer2 reveal that angiotensin-II promotes increases in intracellular H(2)O(2). We used a Rac1 FRET biosensor to show that angiotensin-II promotes Rac1 activation that is attenuated by PEG-catalase. siRNA-mediated Rac1 knockdown blocks angiotensin-II-stimulated MARCKS phosphorylation. Cell imaging studies using a phosphoinositide 4,5-bisphosphate (PIP(2)) biosensor revealed that angiotensin-II PIP(2) regulation depends on MARCKS and H(2)O(2). siRNA-mediated knockdown of MARCKS or Rac1 attenuates receptor-mediated activation of the tyrosine kinase c-Abl and disrupts actin fiber formation. These studies establish a critical role for H(2)O(2) in angiotensin-II signaling to the endothelial cytoskeleton in a novel pathway that is critically dependent on MARCKS, Rac1, and c-Abl.
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Affiliation(s)
- Hermann Kalwa
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Kleveta G, Borzęcka K, Zdioruk M, Czerkies M, Kuberczyk H, Sybirna N, Sobota A, Kwiatkowska K. LPS induces phosphorylation of actin-regulatory proteins leading to actin reassembly and macrophage motility. J Cell Biochem 2012; 113:80-92. [PMID: 21898535 DOI: 10.1002/jcb.23330] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Upon bacterial infection lipopolysaccharide (LPS) induces migration of monocytes/macrophages to the invaded region and production of pro-inflammatory mediators. We examined mechanisms of LPS-stimulated motility and found that LPS at 100 ng/ml induced rapid elongation and ruffling of macrophage-like J774 cells. A wound-healing assay revealed that LPS also activated directed cell movement that was followed by TNF-α production. The CD14 and TLR4 receptors of LPS translocated to the leading lamella of polarized cells, where they transiently colocalized triggering local accumulation of actin filaments and phosphatidylinositol 4,5-bisphosphate. Fractionation of Triton X-100 cell lysates revealed that LPS induced polymerization of cytoskeletal actin filaments by 50%, which coincided with the peak of cell motility. This microfilament population appeared at the expense of short filaments composing the plasma membrane skeleton of unstimulated cells and actin monomers consisting prior to the LPS stimulation about 60% of cellular actin. Simultaneously with actin polymerization, LPS stimulated phosphorylation of two actin-regulatory proteins, paxillin on tyrosine 118 by 80% and N-WASP on serine 484/485 by 20%, and these events preceded activation of NF-κB. LPS-induced protein phosphorylation and reorganization of the actin cytoskeleton were inhibited by PP2, a drug affecting activity of tyrosine kinases of the Src family. The data indicate that paxillin and N-WASP are involved in the reorganization of actin cytoskeleton driving motility of LPS-stimulated cells. Disturbances of actin organization induced by cytochalasin D did not inhibit TNF-α production suggesting that LPS-induced cell motility is not required for TNF-α release.
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Affiliation(s)
- Galyna Kleveta
- Department of Cell Biology, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
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42
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Green TD, Park J, Yin Q, Fang S, Crews AL, Jones SL, Adler KB. Directed migration of mouse macrophages in vitro involves myristoylated alanine-rich C-kinase substrate (MARCKS) protein. J Leukoc Biol 2012; 92:633-9. [PMID: 22623357 DOI: 10.1189/jlb.1211604] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
A role for MARCKS protein in directed migration of macrophages toward a chemoattractant was investigated. A peptide identical to the N-terminus of MARCKS (the MANS peptide), shown previously to inhibit the function of MARCKS in various cell types, was used. We investigated whether this MARCKS-related peptide could affect migration of macrophages, using the mouse macrophage-like J774A.1 cell line and primary murine macrophages. Both of these cell types migrated in response to the chemoattractants macrophage/MCPs, MCP-1 (25-100 ng/ml) or C5a (5-20 ng/ml). Cells were preincubated (15 min) with MANS or a mis-sense control peptide (RNS), both at 50 μM, and effects on migration determined 3 h after addition of chemoattractants. The movement and interactions of MARCKS and actin also were followed visually via confocal microscopy using a fluorescently labeled antibody to MARCKS and fluorescently tagged phalloidin to identify actin. MANS, but not RNS, attenuated migration of J774A.1 cells and primary macrophages in response to MCP-1 or C5a, implicating MARCKS in the cellular mechanism of directed migration. Exposure of cells to MCP-1 resulted in rapid phosphorylation and translocation of MARCKS from plasma membrane to cytosol, whereas actin appeared to spread through the cell and into cell protrusions; there was visual and biochemical evidence of a transient interaction between MARCKS and actin during the process of migration. These results suggest that MARCKS is involved in directed migration of macrophages via a process involving its phosphorylation, cytoplasmic translocation, and interaction with actin.
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Affiliation(s)
- Teresa D Green
- Department of Molecular Biomedical Sciences, North Carolina State University, College of Veterinary Medicine, Raleigh, NC, USA
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Lee S, Jang E, Kim JH, Kim JH, Lee WH, Suk K. Lipocalin-type prostaglandin D2 synthase protein regulates glial cell migration and morphology through myristoylated alanine-rich C-kinase substrate: prostaglandin D2-independent effects. J Biol Chem 2012; 287:9414-28. [PMID: 22275363 DOI: 10.1074/jbc.m111.330662] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Prostaglandin D synthase (PGDS) is responsible for the conversion of PGH(2) to PGD(2). Two distinct types of PGDS have been identified: hematopoietic-type PGDS (H-PGDS) and lipocalin-type PGDS (L-PGDS). L-PGDS acts as both a PGD(2)-synthesizing enzyme and as an extracellular transporter of various lipophilic small molecules. Although L-PGDS is one of the most abundant proteins in the cerebrospinal fluid, little is known about the function of L-PGDS in the central nervous system (CNS). To better understand the role of L-PGDS in the CNS, effects of L-PGDS on the migration and morphology of glial cells were investigated. The L-PGDS protein accelerated the migration of cultured glial cells. Expression of the L-pgds gene was detected in glial cells and neurons. L-PGDS protein also induced morphological changes in glia similar to the characteristic phenotypic changes in reactive gliosis. L-PGDS-induced cell migration was associated with augmented formation of actin filaments and focal adhesion, which was accompanied by activation of AKT, RhoA, and JNK pathways. L-PGDS protein injected into the mouse brain promoted migration and accumulation of astrocytes in vivo. Furthermore, the cell migration-promoting effect of L-PGDS on glial cells was independent of the PGD(2) products. The L-PGDS protein interacted with myristoylated alanine-rich protein kinase C substrate (MARCKS) to promote cell migration. These results demonstrate the critical role of L-PGDS as a secreted lipocalin in the regulation of glial cell migration and morphology. The results also indicate that L-PGDS may participate in reactive gliosis in an autocrine or paracrine manner, and may have pathological implications in neuroinflammatory diseases.
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Affiliation(s)
- Shinrye Lee
- Department of Pharmacology, Brain Science & Engineering Institute, CMRI, Kyungpook National University School of Medicine, Kyungpook National University, Daegu, Korea
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Zhang L, Mao YS, Janmey PA, Yin HL. Phosphatidylinositol 4, 5 bisphosphate and the actin cytoskeleton. Subcell Biochem 2012; 59:177-215. [PMID: 22374091 DOI: 10.1007/978-94-007-3015-1_6] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Dynamic changes in PM PIP(2) have been implicated in the regulation of many processes that are dependent on actin polymerization and remodeling. PIP(2) is synthesized primarily by the type I phosphatidylinositol 4 phosphate 5 kinases (PIP5Ks), and there are three major isoforms, called a, b and g. There is emerging evidence that these PIP5Ks have unique as well as overlapping functions. This review will focus on the isoform-specific roles of individual PIP5K as they relate to the regulation of the actin cytoskeleton. We will review recent advances that establish PIP(2) as a critical regulator of actin polymerization and cytoskeleton/membrane linkages, and show how binding of cytoskeletal proteins to membrane PIP(2) might alter lateral or transverse movement of lipids to affect raft formation or lipid asymmetry. The mechanisms for specifying localized increase in PIP(2) to regulate dynamic actin remodeling will also be discussed.
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Affiliation(s)
- Li Zhang
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, 75390-9040, Dallas, TX, USA
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Johnsson AK, Karlsson R. Synaptotagmin 1 causes phosphatidyl inositol lipid-dependent actin remodeling in cultured non-neuronal and neuronal cells. Exp Cell Res 2011; 318:114-26. [PMID: 22036579 DOI: 10.1016/j.yexcr.2011.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 10/04/2011] [Accepted: 10/06/2011] [Indexed: 11/24/2022]
Abstract
Here we demonstrate that a dramatic actin polymerizing activity caused by ectopic expression of the synaptic vesicle protein synaptotagmin 1 that results in extensive filopodia formation is due to the presence of a lysine rich sequence motif immediately at the cytoplasmic side of the transmembrane domain of the protein. This polybasic sequence interacts with anionic phospholipids in vitro, and, consequently, the actin remodeling caused by this sequence is interfered with by expression of a phosphatidyl inositol (4,5)-bisphosphate (PIP2)-targeted phosphatase, suggesting that it intervenes with the function of PIP2-binding actin control proteins. The activity drastically alters the behavior of a range of cultured cells including the neuroblastoma cell line SH-SY5Y and primary cortical mouse neurons, and, since the sequence is conserved also in synaptotagmin 2, it may reflect an important fine-tuning role for these two proteins during synaptic vesicle fusion and neurotransmitter release.
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Affiliation(s)
- Anna-Karin Johnsson
- Department of Cell Biology, Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
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