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Xia P, Dubrovska A. CD98 heavy chain as a prognostic biomarker and target for cancer treatment. Front Oncol 2023; 13:1251100. [PMID: 37823053 PMCID: PMC10562705 DOI: 10.3389/fonc.2023.1251100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 08/29/2023] [Indexed: 10/13/2023] Open
Abstract
The SLC3A2 gene encodes for a cell-surface transmembrane protein CD98hc (4F2). CD98hc serves as a chaperone for LAT1 (SLC7A5), LAT2 (SLC7A8), y+LAT1 (SLC7A7), y+LAT2 (SLC7A6), xCT (SLC7A11) and Asc1 (SLC7A10) providing their recruitment to the plasma membrane. Together with the light subunits, it constitutes heterodimeric transmembrane amino acid transporters. CD98hc interacts with other surface molecules, such as extracellular matrix metalloproteinase inducer CD147 (EMMPRIN) and adhesion receptors integrins, and regulates glucose uptake. In this way, CD98hc connects the signaling pathways sustaining cell proliferation and migration, biosynthesis and antioxidant defense, energy production, and stem cell properties. This multifaceted role makes CD98hc one of the critical regulators of tumor growth, therapy resistance, and metastases. Indeed, the high expression levels of CD98hc were confirmed in various tumor tissues, including head and neck squamous cell carcinoma, glioblastoma, colon adenocarcinoma, pancreatic ductal adenocarcinoma, and others. A high expression of CD98hc has been linked to clinical prognosis and response to chemo- and radiotherapy in several types of cancer. In this mini-review, we discuss the physiological functions of CD98hc, its role in regulating tumor stemness, metastases, and therapy resistance, and the clinical significance of CD98hc as a tumor marker and therapeutic target.
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Affiliation(s)
- Pu Xia
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Anna Dubrovska
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, Dresden, Germany
- German Cancer Consortium (DKTK), Partner Site Dresden and German Cancer Research Center (DKFZ), Heidelberg, Germany
- National Center for Tumor Diseases (NCT), Partner Site Dresden: German Cancer Research Center (DKFZ), Heidelberg, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, Germany
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Xia P, Liu DH, Wang D, Wen GM, Zhao ZY. SLC3A2, as an indirect target gene of ALDH2, exacerbates alcohol-associated liver cancer via the sphingolipid biosynthesis pathway. Free Radic Biol Med 2023; 206:125-133. [PMID: 37406742 DOI: 10.1016/j.freeradbiomed.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 06/29/2023] [Accepted: 07/03/2023] [Indexed: 07/07/2023]
Abstract
Excessive drinking is one of the main causes of liver cancer. In the process of alcohol metabolism, aldehyde dehydrogenase 2 (ALDH2) is the key enzyme of acetaldehyde metabolism. ALDH2 gene deficiency is positively associated with the risk of hepatocellular carcinoma (HCC). However, no studies have shown a connection between ALDH2 and another metabolic regulatory gene, SLC3A2. In this study, we analyzed the expression levels of ALDH2 and SLC3A2 in liver cancer tissues based on the TCGA database. Subsequently, we constructed ALDH2 knockout and SLC3A2 knock-in transgenic mice to check the roles of ALDH2 and SLC3A2 in tumorigenesis in vivo. In addition, we examined the mechanisms of ALDH2 and SLC3A2 in HCC cells using small RNA interference technology. Consistent with previous studies, we also confirmed the functions of ALDH2 in inhibiting hepatocarcinogenesis, while SLC3A2 had the opposite effect. The main finding of this study is that ALDH2 inhibited BSG expression through the TGF-β1 pathway, which indirectly inhibited SLC3A2 expression; subsequently, the sphingolipid metabolism pathway was also inhibited in HCC cells. Therefore, SLC3A2 is a novel target for HCC treatment.
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Affiliation(s)
- Pu Xia
- Biological Anthropology Institute, Jinzhou Medical University, Jinzhou, Liaoning, PR China; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.
| | - Da-Hua Liu
- Biological Anthropology Institute, Jinzhou Medical University, Jinzhou, Liaoning, PR China
| | - Dan Wang
- College of Human Kinesiology, Shenyang Sport University, Shenyang, Liaoning, PR China
| | - Gui-Min Wen
- Department of Community Nursing, College of Nursing, Jinzhou Medical University, Jinzhou, Liaoning, PR China
| | - Zhen-Ying Zhao
- Department of Pharmacy, Tianjin Union Medical Center, Tianjin, PR China
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Geller C, Maddela J, Tuplano R, Runa F, Adamian Y, Güth R, Ortiz Soto G, Tomaneng L, Cantor J, Kelber JA. Fibronectin, DHPS and SLC3A2 Signaling Cooperate to Control Tumor Spheroid Growth, Subcellular eIF5A1/2 Distribution and CDK4/6 Inhibitor Resistance. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.13.536765. [PMID: 37090582 PMCID: PMC10120696 DOI: 10.1101/2023.04.13.536765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Extracellular matrix (ECM) protein expression/deposition within and stiffening of the breast cancer microenvironment facilitates disease progression and correlates with poor patient survival. However, the mechanisms by which ECM components control tumorigenic behaviors and responses to therapeutic intervention remain poorly understood. Fibronectin (FN) is a major ECM protein controlling multiple processes. In this regard, we previously reported that DHPS-dependent hypusination of eIF5A1/2 is necessary for fibronectin-mediated breast cancer metastasis and epithelial to mesenchymal transition (EMT). Here, we explored the clinical significance of an interactome generated using hypusination pathway components and markers of intratumoral heterogeneity. Solute carrier 3A2 (SLC3A2 or CD98hc) stood out as an indicator of poor overall survival among patients with basal-like breast cancers that express elevated levels of DHPS. We subsequently discovered that blockade of DHPS or SLC3A2 reduced triple negative breast cancer (TNBC) spheroid growth. Interestingly, spheroids stimulated with exogenous fibronectin were less sensitive to inhibition of either DHPS or SLC3A2 - an effect that could be abrogated by dual DHPS/SLC3A2 blockade. We further discovered that a subset of TNBC cells responded to fibronectin by increasing cytoplasmic localization of eIF5A1/2. Notably, these fibronectin-induced subcellular localization phenotypes correlated with a G0/G1 cell cycle arrest. Fibronectin-treated TNBC cells responded to dual DHPS/SLC3A2 blockade by shifting eIF5A1/2 localization back to a nucleus-dominant state, suppressing proliferation and further arresting cells in the G2/M phase of the cell cycle. Finally, we observed that dual DHPS/SLC3A2 inhibition increased the sensitivity of both Rb-negative and -positive TNBC cells to the CDK4/6 inhibitor palbociclib. Taken together, these data identify a previously unrecognized mechanism through which extracellular fibronectin controls cancer cell tumorigenicity by modulating subcellular eIF5A1/2 localization and provides prognostic/therapeutic utility for targeting the cooperative DHPS/SLC3A2 signaling axis to improve breast cancer treatment responses.
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Affiliation(s)
- Cameron Geller
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Joanna Maddela
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Ranel Tuplano
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Farhana Runa
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Yvess Adamian
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Robert Güth
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Gabriela Ortiz Soto
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Luke Tomaneng
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
| | - Joseph Cantor
- BD Biosciences, 1077 N Torrey Pines Rd, La Jolla, CA
| | - Jonathan A. Kelber
- Department of Biology, California State University Northridge, Northridge, CA & Department of Biology, Baylor University, Waco, TX
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Integrin αvβ3 Is a Master Regulator of Resistance to TKI-Induced Ferroptosis in HER2-Positive Breast Cancer. Cancers (Basel) 2023; 15:cancers15041216. [PMID: 36831558 PMCID: PMC9954089 DOI: 10.3390/cancers15041216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/17/2023] Open
Abstract
Human epidermal growth factor receptor-2 (HER2)-targeting therapies provide clinical benefits for patients with HER2-positive breast cancer. However, the resistance to monotherapies invariably develops and leads to disease relapse and treatment failure. Previous studies have demonstrated a link between the potency of HER2-targeting tyrosine kinase inhibitors (TKIs) and their ability to induce an iron-dependent form of cell death called ferroptosis. The aim of this study was to understand the mechanisms of resistance to TKI-induced ferroptosis and identify novel approaches to overcome treatment resistance. We used mouse and human HER2-positive models of acquired TKI resistance to demonstrate an intimate link between the resistance to TKIs and to ferroptosis and present the first evidence that the cell adhesion receptor αvβ3 integrin is a critical mediator of resistance to TKI-induced ferroptosis. Our findings indicate that αvβ3 integrin-mediated resistance is associated with the re-wiring of the iron/antioxidant metabolism and persistent activation of AKT signalling. Moreover, using gene manipulation approaches and pharmacological inhibitors, we show that this "αvβ3 integrin addiction" can be targeted to reverse TKI resistance. Collectively, these findings provide critical insights into new therapeutic strategies to improve the treatment of advanced HER2-positive breast cancer patients.
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Role of integrin and its potential as a novel postmortem biomarker in traumatic axonal injury. Int J Legal Med 2022; 137:843-849. [PMID: 36562807 DOI: 10.1007/s00414-022-02938-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022]
Abstract
Traumatic axonal injury (TAI) accounts for a large proportion of the mortality of traumatic brain injury (TBI). The diagnosis of TAI is currently of limited use for medicolegal purposes. It is known that axons in TAI are diffusely damaged by secondary processes other than direct head injury. However, the physiopathological mechanism of TAI is still elusive. The present study used RGD peptide, an antagonist of the mechanotransduction protein integrin, to explore the role of integrin-transmitted mechanical signalling in the pathogenesis of rat TAI. The rats were subjected to a linearly accelerating load, and changes in beta-amyloid precursor protein (β-APP) expression, skeleton ultrastructure, skeleton protein neurofilament light (NF-L), and α-tubulin in the brainstem were observed, indicating that RGD could relieve the severity of axonal injury in TAI rats. In addition, the expression of β-integrin was stronger and centralized in the brainstem of the deceased died from TAI compared to other nonviolent causes. This study examined the pathophysiology and biomechanics of TAI and assessed the role of integrin in the injury of microtubules and neurofilaments in TAI. Thus, we propose that integrin-mediated cytoskeletal injury plays an important role in TAI and that integrin has the potential as a biomarker for TAI.
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Saha SS, Samanas NB, Miralda I, Shubin NJ, Niino K, Bhise G, Acharya M, Seo AJ, Camp N, Deutsch GH, James RG, Piliponsky AM. Mast cell surfaceome characterization reveals CD98 heavy chain is critical for optimal cell function. J Allergy Clin Immunol 2022; 149:685-697. [PMID: 34324892 PMCID: PMC8792104 DOI: 10.1016/j.jaci.2021.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Mast cells are involved in many distinct pathologic conditions, suggesting that they recognize and respond to various stimuli and thus require a rich repertoire of cell surface proteins. However, mast cell surface proteomes have not been comprehensively characterized. OBJECTIVE We aimed to further characterize the mast cell surface proteome to obtain a better understanding of how mast cells function in health and disease. METHODS We enriched for glycosylated surface proteins expressed in mouse bone marrow-derived cultured mast cells (BMCMCs) and identified them using mass spectrometry analysis. The presence of novel surface proteins in mast cells was validated by real-time quantitative PCR and flow cytometry analysis in BMCMCs and peritoneal mast cells (PMCs). We developed a clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene editing approach to disrupt genes of interest in BMCMCs. RESULTS The glycoprotein enrichment approach resulted in the identification of 1270 proteins in BMCMCs, 378 of which were localized to the plasma membrane. The most common protein classes among plasma membrane proteins were small GTPases, receptors, and transporters. One such cell surface protein was CD98 heavy chain (CD98hc), encoded by the Slc3a2 gene. Slc3a2 gene disruption resulted in a significant reduction in CD98hc expression, adhesion, and proliferation. CONCLUSIONS Glycoprotein enrichment coupled with mass spectrometry can be used to identify novel surface molecules in mast cells. Moreover, CD98hc plays an important role in mast cell function.
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Affiliation(s)
- Siddhartha S. Saha
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Nyssa B. Samanas
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Irina Miralda
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Nicholas J. Shubin
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Kerri Niino
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Gauri Bhise
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Manasa Acharya
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Albert J. Seo
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Nathan Camp
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - Gail H. Deutsch
- Department of Laboratories, Seattle Children’s Research Institute, Seattle, Washington, United States of America,Department of Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Richard G. James
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America,Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Adrian M. Piliponsky
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, United States of America,Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, United States of America,Department of Pathology, University of Washington School of Medicine, Seattle, Washington, United States of America,Department of Global Health, University of Washington School of Medicine, Seattle, Washington, United States of America,Corresponding author: Adrian M. Piliponsky, Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, 1900 9th Ave, Room 721, , Phone number: 206-884-7226, Fax number: 206-987-7310
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Fairweather SJ, Shah N, Brӧer S. Heteromeric Solute Carriers: Function, Structure, Pathology and Pharmacology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 21:13-127. [PMID: 33052588 DOI: 10.1007/5584_2020_584] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Solute carriers form one of three major superfamilies of membrane transporters in humans, and include uniporters, exchangers and symporters. Following several decades of molecular characterisation, multiple solute carriers that form obligatory heteromers with unrelated subunits are emerging as a distinctive principle of membrane transporter assembly. Here we comprehensively review experimentally established heteromeric solute carriers: SLC3-SLC7 amino acid exchangers, SLC16 monocarboxylate/H+ symporters and basigin/embigin, SLC4A1 (AE1) and glycophorin A exchanger, SLC51 heteromer Ost α-Ost β uniporter, and SLC6 heteromeric symporters. The review covers the history of the heteromer discovery, transporter physiology, structure, disease associations and pharmacology - all with a focus on the heteromeric assembly. The cellular locations, requirements for complex formation, and the functional role of dimerization are extensively detailed, including analysis of the first complete heteromer structures, the SLC7-SLC3 family transporters LAT1-4F2hc, b0,+AT-rBAT and the SLC6 family heteromer B0AT1-ACE2. We present a systematic analysis of the structural and functional aspects of heteromeric solute carriers and conclude with common principles of their functional roles and structural architecture.
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Affiliation(s)
- Stephen J Fairweather
- Research School of Biology, Australian National University, Canberra, ACT, Australia. .,Resarch School of Chemistry, Australian National University, Canberra, ACT, Australia.
| | - Nishank Shah
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Stefan Brӧer
- Research School of Biology, Australian National University, Canberra, ACT, Australia.
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Identification by proximity labeling of novel lipidic and proteinaceous potential partners of the dopamine transporter. Cell Mol Life Sci 2021; 78:7733-7756. [PMID: 34709416 PMCID: PMC8629785 DOI: 10.1007/s00018-021-03998-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 10/07/2021] [Accepted: 10/17/2021] [Indexed: 12/05/2022]
Abstract
Dopamine (DA) transporters (DATs) are regulated by trafficking and modulatory processes that probably rely on stable and transient interactions with neighboring proteins and lipids. Using proximity-dependent biotin identification (BioID), we found novel potential partners for DAT, including several membrane proteins, such as the transmembrane chaperone 4F2hc, the proteolipid M6a and a potential membrane receptor for progesterone (PGRMC2). We also detected two cytoplasmic proteins: a component of the Cullin1-dependent ubiquitination machinery termed F-box/LRR-repeat protein 2 (FBXL2), and the enzyme inositol 5-phosphatase 2 (SHIP2). Immunoprecipitation (IP) and immunofluorescence studies confirmed either a physical association or a close spatial proximity between these proteins and DAT. M6a, SHIP2 and the Cullin1 system were shown to increase DAT activity in coexpression experiments, suggesting a functional role for their association. Deeper analysis revealed that M6a, which is enriched in neuronal protrusions (filopodia or dendritic spines), colocalized with DAT in these structures. In addition, the product of SHIP2 enzymatic activity (phosphatidylinositol 3,4-bisphosphate [PI(3,4)P2]) was tightly associated with DAT, as shown by co-IP and by colocalization of mCherry-DAT with a specific biosensor for this phospholipid. PI(3,4)P2 strongly stimulated transport activity in electrophysiological recordings, and conversely, inhibition of SHIP2 reduced DA uptake in several experimental systems including striatal synaptosomes and the dopaminergic cell line SH-SY5Y. In summary, here we report several potential new partners for DAT and a novel regulatory lipid, which may represent new pharmacological targets for DAT, a pivotal protein in dopaminergic function of the brain.
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Banerjee A, Kulkarni S, Mukherjee A. Herpes Simplex Virus: The Hostile Guest That Takes Over Your Home. Front Microbiol 2020; 11:733. [PMID: 32457704 PMCID: PMC7221137 DOI: 10.3389/fmicb.2020.00733] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/30/2020] [Indexed: 12/15/2022] Open
Abstract
Alpha (α)-herpesviruses (HSV-1 and HSV-2), like other viruses, are obligate intracellular parasites. They hijack the cellular machinery to survive and replicate through evading the defensive responses by the host. The viral genome of herpes simplex viruses (HSVs) contains viral genes, the products of which are destined to exploit the host apparatus for their own existence. Cellular modulations begin from the entry point itself. The two main gateways that the virus has to penetrate are the cell membrane and the nuclear membrane. Changes in the cell membrane are triggered when the glycoproteins of HSV interact with the surface receptors of the host cell, and from here, the components of the cytoskeleton take over. The rearrangement in the cytoskeleton components help the virus to enter as well as transport to the nucleus and back to the cell membrane to spread out to the other cells. The entire carriage process is also mediated by the motor proteins of the kinesin and dynein superfamily and is directed by the viral tegument proteins. Also, the virus captures the cell’s most efficient cargo carrying system, the endoplasmic reticulum (ER)–Golgi vesicular transport machinery for egress to the cell membrane. For these reasons, the host cell has its own checkpoints where the normal functions are halted once a danger is sensed. However, a cell may be prepared for the adversities from an invading virus, and it is simply commendable that the virus has the antidote to these cellular strategies as well. The HSV viral proteins are capable of limiting the use of the transcriptional and translational tools for the cell itself, so that its own transcription and translation pathways remain unhindered. HSV prefers to constrain any self-destruction process of the cell—be it autophagy in the lysosome or apoptosis by the mitochondria, so that it can continue to parasitize the cell for its own survival. This review gives a detailed account of the significance of compartmentalization during HSV pathogenesis. It also highlights the undiscovered areas in the HSV cell biology research which demand attention for devising improved therapeutics against the infection.
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Affiliation(s)
- Anwesha Banerjee
- Division of Virology, Indian Council of Medical Research-National AIDS Research Institute, Pune, India
| | - Smita Kulkarni
- Division of Virology, Indian Council of Medical Research-National AIDS Research Institute, Pune, India
| | - Anupam Mukherjee
- Division of Virology, Indian Council of Medical Research-National AIDS Research Institute, Pune, India
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Co-Expression Effect of SLC7A5/SLC3A2 to Predict Response to Endocrine Therapy in Oestrogen-Receptor-Positive Breast Cancer. Int J Mol Sci 2020; 21:ijms21041407. [PMID: 32093034 PMCID: PMC7073058 DOI: 10.3390/ijms21041407] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/15/2020] [Accepted: 02/17/2020] [Indexed: 12/23/2022] Open
Abstract
The majority of breast cancers are oestrogen-receptor-positive (ER+) and are subject to endocrine therapy; however, an unpredictable subgroup of patients will develop resistance to endocrine therapy. The SLC7A5/SLC3A2 complex is a major route for the transport of large neutral essential amino acids through the plasma membrane. Alterations in the expression and function of those amino-acid transporters lead to metabolic reprogramming, which contributes to the tumorigenesis and drug resistance. This study aims to assess the effects and roles of SLC7A5/SLC3A2 co-expression in predicting responses to endocrine therapy in patients with ER+ breast cancer. The biological and clinical impact of SLC7A5/SLC3A2 co-expression was assessed in large annotated cohorts of ER+/HER2− breast cancer with long-term follow-up at the mRNA and protein levels. In vitro experiments were conducted to investigate the effect of SLC7A5/SLC3A2 knockdown in the proliferation of cancer cells and to the sensitivity to tamoxifen. We found that proliferation-related genes are highly expressed in a subgroup of patients with high SLC7A5/SLC3A2, and knockdown of SLC7A5/SLC3A2 decreased proliferation of ER+ breast cancer cells. In patients treated with endocrine therapy, high SLC7A5/SLC3A2 co-expression was associated with poor patient outcome, and depletion of SLC7A5/SLC3A2 using siRNA increased the sensitivity of breast cancer cells to tamoxifen. On the basis of our findings, SLC7A5/SLC3A2 co-expression has the potential of identifying a subgroup of ER+/HER2− breast cancer patients who fail to benefit from endocrine therapy and could guide the choice of other alternative therapies.
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Lu X. The Role of Large Neutral Amino Acid Transporter (LAT1) in Cancer. Curr Cancer Drug Targets 2019; 19:863-876. [DOI: 10.2174/1568009619666190802135714] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/24/2019] [Accepted: 05/31/2019] [Indexed: 12/11/2022]
Abstract
Background:
The solute carrier family 7 (SLC7) can be categorically divided into two
subfamilies, the L-type amino acid transporters (LATs) including SLC7A5-13, and SLC7A15, and
the cationic amino acid transporters (CATs) including SLC7A1-4 and SLC7A14. Members of the
CAT family transport predominantly cationic amino acids by facilitating diffusion with intracellular
substrates. LAT1 (also known as SLC7A5), is defined as a heteromeric amino acid transporter
(HAT) interacting with the glycoprotein CD98 (SLC3A2) through a conserved disulfide to uptake
not only large neutral amino acids, but also several pharmaceutical drugs to cells.
Methods:
In this review, we provide an overview of the interaction of the structure-function of
LAT1 and its essential role in cancer, specifically, its role at the blood-brain barrier (BBB) to facilitate
the transport of thyroid hormones, pharmaceuticals (e.g., I-DOPA, gabapentin), and metabolites
into the brain.
Results:
LAT1 expression increases as cancers progress, leading to higher expression levels in highgrade
tumors and metastases. In addition, LAT1 plays a crucial role in cancer-associated
reprogrammed metabolic networks by supplying tumor cells with essential amino acids.
Conclusion:
The increasing understanding of the role of LAT1 in cancer has led to an increase in
interest surrounding its potential as a drug target for cancer treatment.
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Affiliation(s)
- Xinjie Lu
- The Mary and Garry Weston Molecular Immunology Laboratory, Thrombosis Research Institute, London, SW3 6LR, United Kingdom
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12
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Abstract
Integrins are heterodimeric cell surface receptors ensuring the mechanical connection between cells and the extracellular matrix. In addition to the anchorage of cells to the extracellular matrix, these receptors have critical functions in intracellular signaling, but are also taking center stage in many physiological and pathological conditions. In this review, we provide some historical, structural, and physiological notes so that the diverse functions of these receptors can be appreciated and put into the context of the emerging field of mechanobiology. We propose that the exciting journey of the exploration of these receptors will continue for at least another new generation of researchers.
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Affiliation(s)
- Michael Bachmann
- Department of Cell Physiology and Metabolism, University of Geneva, Centre Médical Universitaire , Geneva , Switzerland ; and Faculty of Medicine and Health Technology, Tampere University, and Fimlab Laboratories , Tampere , Finland
| | - Sampo Kukkurainen
- Department of Cell Physiology and Metabolism, University of Geneva, Centre Médical Universitaire , Geneva , Switzerland ; and Faculty of Medicine and Health Technology, Tampere University, and Fimlab Laboratories , Tampere , Finland
| | - Vesa P Hytönen
- Department of Cell Physiology and Metabolism, University of Geneva, Centre Médical Universitaire , Geneva , Switzerland ; and Faculty of Medicine and Health Technology, Tampere University, and Fimlab Laboratories , Tampere , Finland
| | - Bernhard Wehrle-Haller
- Department of Cell Physiology and Metabolism, University of Geneva, Centre Médical Universitaire , Geneva , Switzerland ; and Faculty of Medicine and Health Technology, Tampere University, and Fimlab Laboratories , Tampere , Finland
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13
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Cui Y, Qin L, Tian D, Wang T, Fan L, Zhang P, Wang Z. ZEB1 Promotes Chemoresistance to Cisplatin in Ovarian Cancer Cells by Suppressing SLC3A2. Chemotherapy 2018; 63:262-271. [PMID: 30481785 DOI: 10.1159/000493864] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 09/14/2018] [Indexed: 11/19/2022]
Abstract
Ovarian cancer is one of the deadliest gynecological malignancies in women. Chemoresistance has been a major obstacle for ovarian cancer treatment. Zinc finger E-box-binding homeobox 1 (ZEB1) is an important regulator of tumor development in various types of cancer. Abnormal expression of SLC3A2 (CD98hc), a type 2 transmembrane cell surface molecule, has been described in several cancers. This study was designed to investigate the role of ZEB1 and SLC3A2 in the chemoresistance to cisplatin in ovarian cancer cells. We found that ZEB1 was increased in cisplatin-resistant SKOV3/DPP cells. Downregulation of ZEB1 significantly decreased cell viability in response to cisplatin, increased cis-platin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. In addition, downregulation of ZEB1 decreased the volume and weight of implanted tumors. SLC3A2 was decreased in cisplatin-resistant SKOV3/DPP cells. Upregulation of SLC3A2 significantly decreased cell viability in response to cisplatin, increased cisplatin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. Moreover, upregulation of SLC3A2 decreased the volume and weight of implanted tumors. Downregulation of ZEB1 resulted in a significant increase of SLC3A2 expression. Moreover, downregulation of SLC3A2 significantly inhibited ZEB1 knockdown-mediated inhibition of cisplatin-resistance. ZEB1-mediated regulation of SLC3A2 was involved in the chemoresistance to cisplatin in ovarian cancer cells. Overall, we provide new insights into the mechanism of chemoresistance to cisplatin in ovarian cancer cells. ZEB1/SLC3A2 may be promising therapeutic targets for enhancement of the sensitivity of ovarian cancer cells to cisplatin-mediated chemotherapy.
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Affiliation(s)
- Yajie Cui
- Department of Obstetrics and Gynecology, Xi'an No. 4 Hospital, Xi'an, China
| | - Li Qin
- Department of Obstetrics and Gynecology, Shaanxi Province People's Hospital, Xi'an, China
| | - Defu Tian
- Department of General Surgery, Shaanxi Provincial Fourth People's Hospital, Xi'an, China
| | - Ting Wang
- Northwest Women and Children's Hospital, Xi'an, China
| | - Lijing Fan
- Department of Obstetrics and Gynecology, Xi'an No. 1 Hospital, Xi'an, China
| | - Peilian Zhang
- Department of Obstetrics and Gynecology, Xi'an No. 1 Hospital, Xi'an, China
| | - Zhongqi Wang
- Department of Gynecology, An Kang Central Hospital, An Kang, China,
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14
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Fuchs R, Stracke A, Holzmann V, Luschin-Ebengreuth G, Meier-Allard N, Ebner N, Lassacher TM, Absenger-Novak M, Fröhlich E, Schittmayer M, Cano Crespo S, Palacin M, Rinner B, Birner-Gruenberger R. Prazosin induced lysosomal tubulation interferes with cytokinesis and the endocytic sorting of the tumour antigen CD98hc. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2018; 1865:1211-1229. [PMID: 29909287 PMCID: PMC6070144 DOI: 10.1016/j.bbamcr.2018.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/28/2018] [Accepted: 06/12/2018] [Indexed: 11/29/2022]
Abstract
The quinazoline based drug prazosin (PRZ) is a potent inducer of apoptosis in human cancer cells. We recently reported that PRZ enters cells via endocytosis and induces tubulation of the endolysosomal system. In a proteomics approach aimed at identifying potential membrane proteins with binding affinity to quinazolines, we detected the oncoprotein CD98hc. We confirmed shuttling of CD98hc towards lysosomes and upregulation of CD98hc expression in PRZ treated cells. Gene knockout (KO) experiments revealed that endocytosis of PRZ still occurs in the absence of CD98hc - suggesting that PRZ does not enter the cell via CD98hc but misroutes the protein towards tubular lysosomes. Lysosomal tubulation interfered with completion of cytokinesis and provoked endoreplication. CD98hc KO cells showed reduced endoreplication capacity and lower sensitivity towards PRZ induced apoptosis than wild type cells. Thus, loss of CD98hc does not affect endocytosis of PRZ and lysosomal tubulation, but the ability for endoreplication and survival of cells. Furthermore, we found that glutamine, lysomototropic agents - namely chloroquine and NH4Cl - as well as inhibition of v-ATPase, interfere with the intracellular transport of CD98hc. In summary, our study further emphasizes lysosomes as target organelles to inhibit proliferation and to induce cell death in cancer. Most importantly, we demonstrate for the first time that the intracellular trafficking of CD98hc can be modulated by small molecules. Since CD98hc is considered as a potential drug target in several types of human malignancies, our study possesses translational significance suggesting, that old drugs are able to act on a novel target.
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Affiliation(s)
- Robert Fuchs
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria.
| | - Anika Stracke
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Viktoria Holzmann
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria; FH JOANNEUM - University of Applied Sciences, Alte Poststraße 149, 8020 Graz, Austria
| | - Gerfried Luschin-Ebengreuth
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Nathalie Meier-Allard
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Nadine Ebner
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Teresa Maria Lassacher
- Chair of Immunology and Pathophysiology, Otto Loewi Research Center, Medical University of Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Markus Absenger-Novak
- Centre for Medical Research, Medical University of Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
| | - Eleonore Fröhlich
- Centre for Medical Research, Medical University of Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
| | - Matthias Schittmayer
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria; Omics Center Graz, BioTechMed-Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
| | - Sara Cano Crespo
- Institute for Research in Biomedicine (IRB-Barcelona), Barcelona Institute of Science and Technology (BIST), Department of Biochemistry and Molecular Biomedicine, University of Barcelona, and CIBERER, Parc Científic de Barcelona. Baldiri I Reixac 10-12, 08028 Barcelona, Spain
| | - Manuel Palacin
- Institute for Research in Biomedicine (IRB-Barcelona), Barcelona Institute of Science and Technology (BIST), Department of Biochemistry and Molecular Biomedicine, University of Barcelona, and CIBERER, Parc Científic de Barcelona. Baldiri I Reixac 10-12, 08028 Barcelona, Spain
| | - Beate Rinner
- Biomedical Research, Medical University of Graz, Roseggerweg 48, 8036 Graz, Austria
| | - Ruth Birner-Gruenberger
- Research Unit Functional Proteomics and Metabolic Pathways, Institute of Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036 Graz, Austria; Omics Center Graz, BioTechMed-Graz, Stiftingtalstrasse 24, 8010 Graz, Austria
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15
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The receptor protein tyrosine phosphatase PTPRJ negatively modulates the CD98hc oncoprotein in lung cancer cells. Oncotarget 2018; 9:23334-23348. [PMID: 29805737 PMCID: PMC5955124 DOI: 10.18632/oncotarget.25101] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 03/24/2018] [Indexed: 01/16/2023] Open
Abstract
PTPRJ, a receptor protein tyrosine phosphatase strongly downregulated in human cancer, displays tumor suppressor activity by negatively modulating several proteins involved in proliferating signals. Here, through a proteomic-based approach, we identified a list of potential PTPRJ-interacting proteins and among them we focused on CD98hc, a type II glycosylated integral membrane protein encoded by SLC3A2, corresponding to the heavy chain of a heterodimeric transmembrane amino-acid transporter, including LAT1. CD98hc is widely overexpressed in several types of cancers and contributes to the process of tumorigenesis by interfering with cell proliferation, adhesion, and migration. We first validated PTPRJ-CD98hc interaction, then demonstrated that PTPRJ overexpression dramatically reduces CD98hc protein levels in A549 lung cancer cells. In addition, following to the treatment of PTPRJ-transduced cells with MG132, a proteasome inhibitor, CD98hc levels did not decrease compared to controls, indicating that PTPRJ is involved in the regulation of CD98hc proteasomal degradation. Moreover, PTPRJ overexpression combined with CD98hc silencing consistently reduced cell proliferation and triggered apoptosis of lung cancer cells. Interestingly, by interrogating the can Evolve database, we observed an inverse correlation between PTPRJ and SLC3A2 gene expression. Indeed, the non-small cell lung cancers (NSCLCs) of patients showing a short survival rate express the lowest and the highest levels of PTPRJ and SLC3A2, respectively. Therefore, the results reported here contribute to shed lights on PTPRJ signaling in cancer cells: moreover, our findings also support the development of a novel anticancer therapeutic approach by targeting the pathway of PTPRJ that is usually downregulated in highly malignant human neoplasias.
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16
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El Ansari R, Craze ML, Diez-Rodriguez M, Nolan CC, Ellis IO, Rakha EA, Green AR. The multifunctional solute carrier 3A2 (SLC3A2) confers a poor prognosis in the highly proliferative breast cancer subtypes. Br J Cancer 2018; 118:1115-1122. [PMID: 29545595 PMCID: PMC5931111 DOI: 10.1038/s41416-018-0038-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 12/31/2022] Open
Abstract
Breast cancer (BC) is a heterogeneous disease characterised by variant biology, metabolic activity and patient outcome. This study aimed to evaluate the biological and prognostic value of the membrane solute carrier, SLC3A2 in BC with emphasis on the intrinsic molecular subtypes. SLC3A2 was assessed at the genomic level, using METABRIC data (n = 1980), and at the proteomic level, using immunohistochemistry on tissue microarray (TMA) sections constructed from a large well-characterised primary BC cohort (n = 2500). SLC3A2 expression was correlated with clinicopathological parameters, molecular subtypes and patient outcome. SLC3A2 mRNA and protein expression were strongly correlated with higher tumour grade and poor Nottingham prognostic index (NPI). High expression of SLC3A2 was observed in triple-negative (TN), HER2+ and ER+ high-proliferation subtypes. SLC3A2 mRNA and protein expression were significantly associated with the expression of c-MYC in all BC subtypes (p < 0.001). High expression of SLC3A2 protein was associated with poor patient outcome (p < 0.001), but only in the ER+ high-proliferation (p = 0.01) and TN (p = 0.04) subtypes. In multivariate analysis SLC3A2 protein was an independent risk factor for shorter BC-specific survival (p < 0.001). SLC3A2 appears to play a role in the aggressive BC subtypes driven by MYC and could act as a potential prognostic marker. Functional assessment is necessary to reveal its potential therapeutic value in the different BC subtypes.
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Affiliation(s)
- Rokaya El Ansari
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Madeleine L Craze
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Maria Diez-Rodriguez
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Christopher C Nolan
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Ian O Ellis
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK.,Breast Institute, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Emad A Rakha
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK.,Breast Institute, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Andrew R Green
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, Nottingham City Hospital, University of Nottingham, Hucknall Road, Nottingham, NG5 1PB, UK.
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17
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Dai Y, Liu H, Liu Y, Zhang Y, He W. EBV transformation induces overexpression of hMSH2/3/6 on B lymphocytes and enhances γδT-cell-mediated cytotoxicity via TCR and NKG2D. Immunology 2018; 154:673-682. [PMID: 29512904 PMCID: PMC6050216 DOI: 10.1111/imm.12920] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 02/28/2018] [Accepted: 02/28/2018] [Indexed: 12/14/2022] Open
Abstract
The engagement of Epstein-Barr virus (EBV)-induced protein ligands in γδ T-cell-mediated anti-EBV immunity, especially in EBV-associated B-cell malignancies, has not been fully elucidated. Previously we reported the overexpression of human MutS homologue 2 (hMSH2), a stress-inducible protein ligand for human γδ T-cells, on EBV-transformed B lymphoblastic cell lines (B-LCLs). In this study, we first generated EBV-transformed B-LCLs from peripheral blood mononuclear cells of healthy volunteers with B95-8 cellular supernatant and cyclosporine A. Secondly, we demonstrated the significantly elevated cell surface protein expression and mRNA transcription of hMSH2 in EBV-transformed B-LCLs, 3D5 and EBV-positive B lymphoma cell line Daudi and Raji. Thirdly, hMSH2-mediated recognition of EBV-transformed B malignant cells by human γδ T-cells was confirmed by specific antibody blocking and siRNA interference. Both TCRγδ and NKG2D participated in hMSH2-mediated recognition of EBV-transformed B malignant cells. Furthermore, hMSH3 and hMSH6, the companion proteins of hMSH2, along with CD98, were found overexpressed on the surface of EBV-transformed malignant B-cells. We concluded that the induced overexpression of hMSH proteins might serve as early alerting biomarkers emerged in EBV-related B-cell malignances or as potential targets for establishing γδ T-cell-based therapeutic immunotherapies towards EBV infection.
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Affiliation(s)
- Yu‐mei Dai
- Department of Clinical Laboratory MedicineGuangzhou Women and Children's Medical CentreGuangzhou Medical UniversityGuangzhouChina
| | - Hai‐ying Liu
- Department of Clinical Laboratory MedicineGuangzhou Women and Children's Medical CentreGuangzhou Medical UniversityGuangzhouChina
| | - Yun‐feng Liu
- Department of Clinical Laboratory MedicineGuangzhou Women and Children's Medical CentreGuangzhou Medical UniversityGuangzhouChina
| | - Yuan Zhang
- Department of Clinical Laboratory MedicineGuangzhou Women and Children's Medical CentreGuangzhou Medical UniversityGuangzhouChina
| | - Wei He
- Department of ImmunologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences and School of Peking Union Medical CollegeBeijingChina
- The National Key Laboratory of Medical Molecular BiologyBeijingChina
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18
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Quantitative membrane proteomics reveals a role for tetraspanin enriched microdomains during entry of human cytomegalovirus. PLoS One 2017; 12:e0187899. [PMID: 29121670 PMCID: PMC5679760 DOI: 10.1371/journal.pone.0187899] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 10/27/2017] [Indexed: 12/15/2022] Open
Abstract
Human cytomegalovirus (HCMV) depends on and modulates multiple host cell membrane proteins during each stage of the viral life cycle. To gain a global view of the impact of HCMV-infection on membrane proteins, we analyzed HCMV-induced changes in the abundance of membrane proteins in fibroblasts using stable isotope labeling with amino acids (SILAC), membrane fractionation and protein identification by two-dimensional liquid chromatography and tandem mass spectrometry. This systematic approach revealed that CD81, CD44, CD98, caveolin-1 and catenin delta-1 were down-regulated during infection whereas GRP-78 was up-regulated. Since CD81 downregulation was also observed during infection with UV-inactivated virus we hypothesized that this tetraspanin is part of the viral entry process. Interestingly, additional members of the tetraspanin family, CD9 and CD151, were also downregulated during HCMV-entry. Since tetraspanin-enriched microdomains (TEM) cluster host cell membrane proteins including known CMV receptors such as integrins, we studied whether TEMs are required for viral entry. When TEMs were disrupted with the cholesterol chelator methyl-β-cylcodextrin, viral entry was inhibited and this inhibition correlated with reduced surface levels of CD81, CD9 and CD151, whereas integrin levels remained unchanged. Furthermore, simultaneous siRNA-mediated knockdown of multiple tetraspanins inhibited viral entry whereas individual knockdown had little effect suggesting essential, but redundant roles for individual tetraspanins during entry. Taken together, our data suggest that TEM act as platforms for receptors utilized by HCMV for entry into cells.
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19
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RalBP1 and p19-VHL play an oncogenic role, and p30-VHL plays a tumor suppressor role during the blebbishield emergency program. Cell Death Discov 2017; 3:17023. [PMID: 28580172 PMCID: PMC5447132 DOI: 10.1038/cddiscovery.2017.23] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 03/28/2017] [Accepted: 04/04/2017] [Indexed: 01/10/2023] Open
Abstract
Cancer stem cells evade apoptotic death by blebbishield emergency program, which constructs blebbishields from apoptotic bodies and drives cellular transformation. Von Hippel-Lindau (VHL) plays both tumor suppressor and oncogenic roles, and the reason behind is poorly understood. Here we demonstrate that dimers and trimers of p19-VHL interact with RalBP1 to construct blebbishields. Expression of RalBP1, p19-VHL, and high-molecular weight VHL is required to evade apoptosis by blebbishield-mediated transformation. In contrast, p30-VHL plays a tumor suppressor role by inhibiting blebbishield-mediated transformation. Furthermore, target genes of VHL that suppress oxidative stress were elevated during blebbishield-mediated cellular transformation. Thus, RalBP1 and p19-VHL play an oncogenic role, whereas p30-VHL plays a tumor suppressor role during the blebbishield emergency program by regulating oxidative stress management genes.
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20
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Herpes Simplex Virus 1 UL34 Protein Regulates the Global Architecture of the Endoplasmic Reticulum in Infected Cells. J Virol 2017; 91:JVI.00271-17. [PMID: 28356536 DOI: 10.1128/jvi.00271-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 03/21/2017] [Indexed: 11/20/2022] Open
Abstract
Upon herpes simplex virus 1 (HSV-1) infection, the CD98 heavy chain (CD98hc) is redistributed around the nuclear membrane (NM), where it promotes viral de-envelopment during the nuclear egress of nucleocapsids. In this study, we attempted to identify the factor(s) involved in CD98hc accumulation and demonstrated the following: (i) the null mutation of HSV-1 UL34 caused specific dispersion throughout the cytoplasm of CD98hc and the HSV-1 de-envelopment regulators, glycoproteins B and H (gB and gH); (ii) as observed with CD98hc, gB, and gH, wild-type HSV-1 infection caused redistribution of the endoplasmic reticulum (ER) markers calnexin and ERp57 around the NM, whereas the UL34-null mutation caused cytoplasmic dispersion of these markers; (iii) the ER markers colocalized efficiently with CD98hc, gB, and gH in the presence and absence of UL34 in HSV-1-infected cells; (iv) at the ultrastructural level, wild-type HSV-1 infection caused ER compression around the NM, whereas the UL34-null mutation caused cytoplasmic dispersion of the ER; and (v) the UL34-null mutation significantly decreased the colocalization efficiency of lamin protein markers of the NM with CD98hc and gB. Collectively, these results indicate that HSV-1 infection causes redistribution of the ER around the NM, with resulting accumulation of ER-associated CD98hc, gB, and gH around the NM and that UL34 is required for ER redistribution, as well as for efficient recruitment to the NM of the ER-associated de-envelopment factors. Our study suggests that HSV-1 induces remodeling of the global ER architecture for recruitment of regulators mediating viral nuclear egress to the NM.IMPORTANCE The ER is an important cellular organelle that exists as a complex network extending throughout the cytoplasm. Although viruses often remodel the ER to facilitate viral replication, information on the effects of herpesvirus infections on ER morphological integrity is limited. Here, we showed that HSV-1 infection led to compression of the global ER architecture around the NM, resulting in accumulation of ER-associated regulators associated with nuclear egress of HSV-1 nucleocapsids. We also identified HSV-1 UL34 as a viral factor that mediated ER remodeling. Furthermore, we demonstrated that UL34 was required for efficient targeting of these regulators to the NM. To our knowledge, this is the first report showing that a herpesvirus remodels ER global architecture. Our study also provides insight into the mechanism by which the regulators for HSV-1 nuclear egress are recruited to the NM, where this viral event occurs.
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21
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Baumer Y, McCurdy S, Alcala M, Mehta N, Lee BH, Ginsberg MH, Boisvert WA. CD98 regulates vascular smooth muscle cell proliferation in atherosclerosis. Atherosclerosis 2017; 256:105-114. [PMID: 28012647 PMCID: PMC5276722 DOI: 10.1016/j.atherosclerosis.2016.11.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 11/10/2016] [Accepted: 11/15/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND AND AIMS Vascular smooth muscle cells (VSMC) migrate and proliferate to form a stabilizing fibrous cap that encapsulates atherosclerotic plaques. CD98 is a transmembrane protein made of two subunits, CD98 heavy chain (CD98hc) and one of six light chains, and is known to be involved in cell proliferation and survival. Because the influence of CD98hc on atherosclerosis development is unknown, our aim was to determine if CD98hc expressed on VSMC plays a role in shaping the morphology of atherosclerotic plaques by regulating VSMC function. METHODS In addition to determining the role of CD98hc in VSMC proliferation and apoptosis, we utilized mice with SMC-specific deletion of CD98hc (CD98hcfl/flSM22αCre+) to determine the effects of CD98hc deficiency on VSMC function in atherosclerotic plaque. RESULTS After culturing for 5 days in vitro, CD98hc-/- VSMC displayed dramatically reduced cell counts, reduced proliferation, as well as reduced migration compared to control VSMC. Analysis of aortic VSCM after 8 weeks of HFD showed a reduction in CD98hc-/- VSMC proliferation as well as increased apoptosis compared to controls. A long-term atherosclerosis study using SMC-CD98hc-/-/ldlr-/- mice was performed. Although total plaque area was unchanged, CD98hc-/- mice showed reduced presence of VSMC within the plaque (2.1 ± 0.4% vs. 4.3 ± 0.4% SM22α-positive area per plaque area, p < 0.05), decreased collagen content, as well as increased necrotic core area (25.8 ± 1.9% vs. 10.9 ± 1.6%, p < 0.05) compared to control ldlr-/- mice. CONCLUSIONS We conclude that CD98hc is required for VSMC proliferation, and that its deficiency leads to significantly reduced presence of VSMC in the neointima. Thus, CD98hc expression in VSMC contributes to the formation of plaques that are morphologically more stable, and thereby protects against atherothrombosis.
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MESH Headings
- Animals
- Apoptosis
- Atherosclerosis/genetics
- Atherosclerosis/metabolism
- Atherosclerosis/pathology
- Cell Movement
- Cell Proliferation
- Cells, Cultured
- Disease Models, Animal
- Elastin/metabolism
- Fusion Regulatory Protein 1, Heavy Chain/genetics
- Fusion Regulatory Protein 1, Heavy Chain/metabolism
- Genetic Predisposition to Disease
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Necrosis
- Neointima
- Phenotype
- Plaque, Atherosclerotic
- Receptors, LDL/deficiency
- Receptors, LDL/genetics
- Rupture, Spontaneous
- Time Factors
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Affiliation(s)
- Yvonne Baumer
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Sara McCurdy
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Martin Alcala
- Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad CEU San Pablo, Madrid, Spain
| | - Nehal Mehta
- Section of Inflammation and Cardiometabolic Diseases, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States
| | - Bog-Hieu Lee
- Department of Food and Nutrition, School of Food Science and Technology, Chung-Ang University, Seoul, South Korea.
| | - Mark H Ginsberg
- Department of Medicine, University of California San Diego, La Jolla, CA, United States
| | - William A Boisvert
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States; Kazan Federal University, Kazan, Russia.
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22
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Bianconi D, Unseld M, Prager GW. Integrins in the Spotlight of Cancer. Int J Mol Sci 2016; 17:ijms17122037. [PMID: 27929432 PMCID: PMC5187837 DOI: 10.3390/ijms17122037] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 11/17/2016] [Accepted: 11/28/2016] [Indexed: 02/07/2023] Open
Abstract
Integrins are heterodimeric cell surface receptors that bind to different extracellular ligands depending on their composition and regulate all processes which enable multicellular life. In cancer, integrins trigger and play key roles in all the features that were once described as the Hallmarks of Cancer. In this review, we will discuss the contribution of integrins to these hallmarks, including uncontrolled and limitless proliferation, invasion of tumor cells, promotion of tumor angiogenesis and evasion of apoptosis and resistance to growth suppressors, by highlighting the latest findings. Further on, given the paramount role of integrins in cancer, we will present novel strategies for integrin inhibition that are starting to emerge, promising a hopeful future regarding cancer treatment.
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Affiliation(s)
- Daniela Bianconi
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, A-1090 Vienna, Austria.
| | - Matthias Unseld
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, A-1090 Vienna, Austria.
| | - Gerald W Prager
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, A-1090 Vienna, Austria.
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23
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18F-fluorodihydroxyphenylalanine PET/CT in pheochromocytoma and paraganglioma: relation to genotype and amino acid transport system L. Eur J Nucl Med Mol Imaging 2016; 44:812-821. [PMID: 27900521 DOI: 10.1007/s00259-016-3586-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 11/22/2016] [Indexed: 01/01/2023]
Abstract
PURPOSE F-FDOPA is a highly sensitive and specific radiopharmaceutical for pheochromocytoma and paraganglioma (PPGL) imaging. However, 18F-FDOPA might be falsely negative in these tumors, especially those related to mutations in succinate dehydrogenase genes (SDHx). The aim of the present study was to evaluate the relationship between expression of L-DOPA transporters and 18F-FDOPA PET imaging results in PPGL. METHODS From 2007 to 2015, 175 patients with non-metastatic PPGL were evaluated by 18F-FDOPA PET/CT for initial diagnosis/staging and follow-up. 18F-FDOPA PET/CT was considered as falsely negative for at least one lesion in 10/126 (8%) patients (two sporadic, six SDHD, two SDHB PPGLs). The mRNA and protein expression levels of CD98hc and LATs were evaluated in samples with different genetic backgrounds and imaging phenotypes. The qRT-PCR and immunohistochemical analyses were performed in 14 and 16 tumor samples, respectively. RESULTS The SDHx mutated samples exhibited a significant decrease in mRNA expression of LAT3 when compared to sporadic PPGLs (P = 0.042). There was also a statistical trend toward decreased CD98hc (P = 0.147) and LAT4 (P = 0.012) levels in SDHx vs sporadic PPGLs. No difference was observed for LAT1/LAT2 mRNA levels. LAT1 protein was expressed in 15 out of 16 (93.75%) SDHx tumors, regardless of the 18F-FDOPA positivity. LAT1 and CD98hc were co-expressed in 6/8 18F-FDOPA-negative PPGLs. In contrast, in one case with absence of LAT1/CD98hc, 18F-FDOPA uptake was positive and attributed to LAT4 expression. CONCLUSIONS We conclude that down-regulation of LAT1/CD98hc cannot explain the imaging phenotype of SDHx-related PPGLs. A reduced activity of LAT1 remains the primary hypothesis possibly due to a modification of intracellular amino acid content which may reduce 18F-FDOPA uptake.
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Dominant Suppression of β1 Integrin by Ectopic CD98-ICD Inhibits Hepatocellular Carcinoma Progression. Int J Mol Sci 2016; 17:ijms17111882. [PMID: 27834933 PMCID: PMC5133882 DOI: 10.3390/ijms17111882] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/28/2016] [Accepted: 11/01/2016] [Indexed: 01/31/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is currently the third most common cause of cancer-related death in the Asia-Pacific region. Our previous work showed that knockdown of CD98 significantly inhibits malignant HCC cell phenotypes in vitro and in vivo. The level of CD98 in the membrane is tightly regulated to mediate complex processes associated with cell–cell communication and intracellular signaling. In addition, the intracellular domain of CD98 (CD98-ICD) seems to be of vital importance for recycling CD98 to the membrane after it is endocytosed. The intracellular and transmembrane domains of CD98 associate with β-integrins (primarily β1 but also β3), and this association is essential for CD98 mediation of integrin-like signaling and complements dominant suppression of β1-integrin. We speculated that isolated CD98-ICD would similarly suppress β1-integrin activation and inhibit the malignant behaviors of cancer cells. In particular, the exact role of CD98-ICD has not been studied independently in HCC. In this study, we found that ectopic expression of CD98-ICD inhibited the malignant phenotypes of HCC cells, and the mechanism possibly involves β1-integrin suppression. Moreover, the expression levels of CD98, β1-integrin-A (the activated form of β1-integrin) and Ki-67 were significantly increased in HCC tissues relative to those of normal liver tissues. Therefore, our preliminary study indicates that ectopic CD98-ICD has an inhibitory role in the malignant development of HCC, and shows that CD98-ICD acts as a dominant negative mutant of CD98 that attenuates β1-integrin activation. CD98-ICD may emerge as a promising candidate for antitumor treatment.
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Kim MY, Cho JY. Molecular association of CD98, CD29, and CD147 critically mediates monocytic U937 cell adhesion. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:515-23. [PMID: 27610038 PMCID: PMC5014998 DOI: 10.4196/kjpp.2016.20.5.515] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/05/2016] [Accepted: 07/25/2016] [Indexed: 12/15/2022]
Abstract
Adhesion events of monocytes represent an important step in inflammatory responses induced by chemokines. The β1-integrin CD29 is a major adhesion molecule regulating leukocyte migration and extravasation. Although several adhesion molecules have been known as regulators of CD29, the molecular interactions between CD29 and its regulatory adhesion molecules (such as CD98 and CD147) have not been fully elucidated. Therefore, in this study, we examined whether these molecules are functionally, biochemically, and cell-biologically associated using monocytic U937 cells treated with aggregation-stimulating and blocking antibodies, as well as enzyme inhibitors. The surface levels of CD29, CD98, and CD147 (but not CD43, CD44, and CD82) were increased. The activation of CD29, CD98, and CD147 by ligation of them with aggregation-activating antibodies triggered the induction of cell-cell adhesion, and sensitivity to various enzyme inhibitors and aggregation-blocking antibodies was similar for CD29-, CD98-, and CD147-induced U937 cell aggregation. Molecular association between these molecules and the actin cytoskeleton was confirmed by confocal microscopy and immunoprecipitation. These results strongly suggest that CD29 might be modulated by its biochemical and cellular regulators, including CD98 and CD147, via the actin cytoskeleton.
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Affiliation(s)
- Mi-Yeon Kim
- School of Systems Biomedical Science, Soongsil University, Seoul 06978, Korea
| | - Jae Youl Cho
- Depatment of Genetic Engineering, Sungkyunkwan University, Suwon 16419, Korea
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Xiao B, Ma P, Viennois E, Merlin D. Urocanic acid-modified chitosan nanoparticles can confer anti-inflammatory effect by delivering CD98 siRNA to macrophages. Colloids Surf B Biointerfaces 2016; 143:186-193. [PMID: 27011348 PMCID: PMC4856589 DOI: 10.1016/j.colsurfb.2016.03.035] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 02/18/2016] [Accepted: 03/10/2016] [Indexed: 01/17/2023]
Abstract
CD98 plays an important role in the development and progression of inflammation. Here, CD98 siRNA (siCD98) was complexed with urocanic acid-modified chitosan (UAC) to form nanoparticles (NPs), which were transfected into Raw 264.7 macrophages in an effort to convey anti-inflammatory effects. Characterization showed that the generated NPs had a desirable particle size (156.0-247.1nm), a slightly positive zeta potential (15.8-17.5mV), and no apparent cytotoxicity against Raw 264.7 macrophages and colon-26 cells compared to control NPs fabricated by Oligofectamine (OF) and siRNA. Cellular uptake experiments demonstrated that macrophages exhibited a time-dependent accumulation profile of UAC/siRNA NPs. Further in vitro gene silencing experiments revealed that UAC/siCD98 NPs with a weight ratio of 60:1 yielded the most efficient knockdowns of CD98 and the pro-inflammatory cytokine, TNF-α. Indeed, the RNAi efficiency obtained with our NPs was even higher than that of the positive control OF/siCD98 NPs. These results suggest that UAC/siCD98 NPs might be a safe, efficient and promising candidate for the treatment of inflammatory disease.
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Affiliation(s)
- Bo Xiao
- Institute for Clean Energy and Advanced Materials, Faculty for Materials and Energy, Southwest University, Chongqing 400715, PR China; Center for Diagnostics and Therapeutics, Institute for Biomedical Science, Georgia State University, Atlanta 30302, USA.
| | - Panpan Ma
- Institute for Clean Energy and Advanced Materials, Faculty for Materials and Energy, Southwest University, Chongqing 400715, PR China
| | - Emilie Viennois
- Center for Diagnostics and Therapeutics, Institute for Biomedical Science, Georgia State University, Atlanta 30302, USA; Atlanta Veterans Affairs Medical Center, Decatur 30033, USA
| | - Didier Merlin
- Center for Diagnostics and Therapeutics, Institute for Biomedical Science, Georgia State University, Atlanta 30302, USA; Atlanta Veterans Affairs Medical Center, Decatur 30033, USA
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Wu B, Wang Y, Yang XM, Xu BQ, Feng F, Wang B, Liang Q, Li Y, Zhou Y, Jiang JL, Chen ZN. Basigin-mediated redistribution of CD98 promotes cell spreading and tumorigenicity in hepatocellular carcinoma. J Exp Clin Cancer Res 2015; 34:110. [PMID: 26437640 PMCID: PMC4594993 DOI: 10.1186/s13046-015-0226-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 09/29/2015] [Indexed: 11/10/2022] Open
Abstract
Background Dysregulated endocytosis of membrane proteins contributes significantly to several hallmarks of cancer. Basigin can enhance cancer progression, but its precise mechanism remains unclear. CD98 promotes cell spreading and tumorigenicity by triggering integrin clustering and enhancing cell adhesion to the extracellular matrix. The endocytosis and recyle of basigin and CD98 might play critical roles in cancer. Methods The role of CD98 was confirmed in liver cancer cells by cell spreading in vitro and tumorigenicity by nude mice xenograft tumor assay in vivo; membrane expression of basigin and CD98 in SMMC-7721 was measured by FCAS; pull down and SPR analysis were uses to reveal the direct association between basigin and CD98; DsRed1 tagged CD98 was blocked in the cytoplasm in K7721 (whose basigin was knockn out) and had a well colocalization with ER and Rab5a positive recycling endosomes under co-focal; finally, by FRET imaging and FCAS we observed the internalization of basigin and CD98 was flotillin-1-regulated, and their recycle at early steps was Arf6-mediated. Results Basigin and CD98 were highly expressed and co-localized on the human hepatocellular carcinoma (HCC) cell membrane; basigin can directly bind to CD98, mediating CD98 redistribution on the HCC cell membrane and activating the downstream integrin signaling pathway. Internalization of basigin and CD98 was flotillin-1 regulated the and their recycling was mediated by Arf6. This recycling process for basigin and CD98 promotes cell spreading and tumor growth in liver cancer xenografts. Conclusion Basigin, as a redistribution chaperone of CD98, plays a critical role in promoting cell spreading and the progression of hepatocellular carcinoma. Electronic supplementary material The online version of this article (doi:10.1186/s13046-015-0226-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bo Wu
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Yi Wang
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Xiang-Min Yang
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Bao-Qing Xu
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Fei Feng
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Bin Wang
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Qiang Liang
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Yu Li
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Yang Zhou
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Jian-Li Jiang
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
| | - Zhi-Nan Chen
- Cell Engineering Research Centre & Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, P. R. China.
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Bianconi D, Schuler A, Pausz C, Geroldinger A, Kaider A, Lenz HJ, Kornek G, Scheithauer W, Zielinski CC, Pabinger I, Ay C, Prager GW. Integrin beta-3 genetic variants and risk of venous thromboembolism in colorectal cancer patients. Thromb Res 2015; 136:865-9. [PMID: 26440977 PMCID: PMC7496222 DOI: 10.1016/j.thromres.2015.08.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/12/2015] [Accepted: 08/16/2015] [Indexed: 11/16/2022]
Abstract
Background Integrin β3 is involved in tumor and endothelial cell biology as well as in platelet aggregation. Herein, we evaluated the predictive potential of three germline single nucleotide polymorphisms (SNPs) in the integrin β3 gene (rs3809865, rs5918 and rs4642) to predict the risk of venous thromboembolism (VTE) in colorectal cancer (CRC) patients, which is one of the leading causes of death among cancer patients. Methods 112 patients diagnosed with CRC enrolled in the prospective Vienna Cancer and Thrombosis Study (CATS) were assessed with a median follow-up of 46 months. DNA was isolated from venous blood samples and SNPs were analyzed by the PCR-RFLP method. Results VTE occurred in 12% (n = 13) of all patients. The SNPs rs5918 and rs4642 were not associated with VTE risk. For rs3809565, 23% (n = 11) of patients had the A/A genotype, 4% (n = 2) had the A/T genotype, but none (0%) had the T/T genotype. In the univariate analysis, patients with the A/A genotype had a significantly higher risk to develop VTE compared to the other polymorphisms (P = 0.0005 after Fine and Gray). In the multivariable analysis, the predictive value remained significant. Conclusions This study identified the rs3809865 A/A genotype as an independent risk factor for VTE in CRC patients. Our findings would help identify high risk patients and would be essential for tailored anticoagulant prophylaxis.
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Affiliation(s)
- Daniela Bianconi
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Alexandra Schuler
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Clemens Pausz
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Angelika Geroldinger
- Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Austria
| | - Alexandra Kaider
- Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Austria
| | - Heinz-Josef Lenz
- Norris Cancer Center, University of Southern California, Los Angeles, CA, USA
| | - Gabriela Kornek
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Werner Scheithauer
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Christoph C Zielinski
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Ingrid Pabinger
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Cihan Ay
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria.
| | - Gerald W Prager
- Department of Internal Medicine I, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria.
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Abstract
Bone metastasis is a common burden in many types of cancer and has a severe impact on the quality of life in patients. Hence, specific therapeutic strategies inhibiting tumor induced osteolysis are urgently needed. In this study, we aimed to interfere with integrin adhesion receptors, which are central players of the bone resorption process. For this purpose, we used cilengitide, a cyclic RGD peptide, which blocks integrin αVβ3 and αVβ5-ligand binding. Our results revealed that cilengitide blocked osteoclast maturation in a dose-dependent manner. In detail, pre-osteoclasts treated with cilengitide exhibited reduced cell spreading, cell migration and cell adhesion on RGD-containing matrix proteins, which are ligands of integrin αV. The activation of the most upstream signal transduction molecules of the integrin receptor-initiated pathway, FAK and c-Src, were consistently blocked by cilengitide. First evidence suggests that cilengitide might interfere with metastatic bone disease in vivo and this study describes a potential underlying mechanism of the inhibitory effect of cilengitide on αV-integrin expressing pre-osteoclasts by blocking integrin ligand binding and interfering with osteoclast maturation and cell behavior. In conclusion, our findings suggest that cilengitide, which interferes with αV-integrins on osteoclasts, may represent a novel therapeutic strategy in the treatment of malignant bone disease.
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Chen CL, Chung T, Wu CC, Ng KF, Yu JS, Tsai CH, Chang YS, Liang Y, Tsui KH, Chen YT. Comparative Tissue Proteomics of Microdissected Specimens Reveals Novel Candidate Biomarkers of Bladder Cancer. Mol Cell Proteomics 2015; 14:2466-78. [PMID: 26081836 DOI: 10.1074/mcp.m115.051524] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Indexed: 12/22/2022] Open
Abstract
More than 380,000 new cases of bladder cancer are diagnosed worldwide, accounting for ∼150,200 deaths each year. To discover potential biomarkers of bladder cancer, we employed a strategy combining laser microdissection, isobaric tags for relative and absolute quantitation labeling, and liquid chromatography-tandem MS (LC-MS/MS) analysis to profile proteomic changes in fresh-frozen bladder tumor specimens. Cellular proteins from four pairs of surgically resected primary bladder cancer tumor and adjacent nontumorous tissue were extracted for use in two batches of isobaric tags for relative and absolute quantitation experiments, which identified a total of 3220 proteins. A DAVID (database for annotation, visualization and integrated discovery) analysis of dysregulated proteins revealed that the three top-ranking biological processes were extracellular matrix organization, extracellular structure organization, and oxidation-reduction. Biological processes including response to organic substances, response to metal ions, and response to inorganic substances were highlighted by up-expressed proteins in bladder cancer. Seven differentially expressed proteins were selected as potential bladder cancer biomarkers for further verification. Immunohistochemical analyses showed significantly elevated levels of three proteins-SLC3A2, STMN1, and TAGLN2-in tumor cells compared with noncancerous bladder epithelial cells, and suggested that TAGLN2 could be a useful tumor tissue marker for diagnosis (AUC = 0.999) and evaluating lymph node metastasis in bladder cancer patients. ELISA results revealed significantly increased urinary levels of both STMN1 and TAGLN2 in bladder cancer subgroups compared with control groups. In comparisons with age-matched hernia urine specimens, urinary TAGLN2 in bladder cancer samples showed the largest fold change (7.13-fold), with an area-under-the-curve value of 0.70 (p < 0.001, n = 205). Overall, TAGLN2 showed the most significant overexpression in individual bladder cancer tissues and urine specimens, and thus represents a potential biomarker for noninvasive screening for bladder cancer. Our findings highlight the value of bladder tissue proteome in providing valuable information for future validation studies of potential biomarkers in urothelial carcinoma.
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Affiliation(s)
- Chien-Lun Chen
- From the ‡Department of Urology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; §School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Ting Chung
- ¶Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Chih-Ching Wu
- ¶Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan; ‖Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kwai-Fong Ng
- **Department of Pathology, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Jau-Song Yu
- ¶Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan; ‡‡Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Cheng-Han Tsai
- ‡‡Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Sun Chang
- ¶Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan; ‡‡Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Ying Liang
- ¶Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Ke-Hung Tsui
- From the ‡Department of Urology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; §School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yi-Ting Chen
- ¶Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan; ‡‡Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan; §§Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
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Herpes Simplex Virus 1 Recruits CD98 Heavy Chain and β1 Integrin to the Nuclear Membrane for Viral De-Envelopment. J Virol 2015; 89:7799-812. [PMID: 25995262 DOI: 10.1128/jvi.00741-15] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/11/2015] [Indexed: 01/08/2023] Open
Abstract
UNLABELLED Herpesviruses have evolved a unique mechanism for nucleocytoplasmic transport of nascent nucleocapsids: the nucleocapsids bud through the inner nuclear membrane (INM; primary envelopment), and the enveloped nucleocapsids then fuse with the outer nuclear membrane (de-envelopment). Little is known about the molecular mechanism of herpesviral de-envelopment. We show here that the knockdown of both CD98 heavy chain (CD98hc) and its binding partner β1 integrin induced membranous structures containing enveloped herpes simplex virus 1 (HSV-1) virions that are invaginations of the INM into the nucleoplasm and induced aberrant accumulation of enveloped virions in the perinuclear space and in the invagination structures. These effects were similar to those of the previously reported mutation(s) in HSV-1 proteins gB, gH, UL31, and/or Us3, which were shown here to form a complex(es) with CD98hc in HSV-1-infected cells. These results suggested that cellular proteins CD98hc and β1 integrin synergistically or independently regulated HSV-1 de-envelopment, probably by interacting directly and/or indirectly with these HSV-1 proteins. IMPORTANCE Certain cellular and viral macromolecular complexes, such as Drosophila large ribonucleoprotein complexes and herpesvirus nucleocapsids, utilize a unique vesicle-mediated nucleocytoplasmic transport: the complexes acquire primary envelopes by budding through the inner nuclear membrane into the space between the inner and outer nuclear membranes (primary envelopment), and the enveloped complexes then fuse with the outer nuclear membrane to release de-enveloped complexes into the cytoplasm (de-envelopment). However, there is a lack of information on the molecular mechanism of de-envelopment fusion. We report here that HSV-1 recruited cellular fusion regulatory proteins CD98hc and β1 integrin to the nuclear membrane for viral de-envelopment fusion. This is the first report of cellular proteins required for efficient de-envelopment of macromolecular complexes during their nuclear egress.
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Fei F, Li X, Xu L, Li D, Zhang Z, Guo X, Yang H, Chen Z, Xing J. CD147-CD98hc Complex Contributes to Poor Prognosis of Non-Small Cell Lung Cancer Patients Through Promoting Cell Proliferation Via the PI3K/Akt Signaling Pathway. Ann Surg Oncol 2014; 21:4359-68. [DOI: 10.1245/s10434-014-3816-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Indexed: 01/21/2023]
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Downregulation of LAT1 expression suppresses cholangiocarcinoma cell invasion and migration. Cell Signal 2014; 26:1668-79. [DOI: 10.1016/j.cellsig.2014.04.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 03/26/2014] [Accepted: 04/04/2014] [Indexed: 01/26/2023]
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Garrigues HJ, DeMaster LK, Rubinchikova YE, Rose TM. KSHV attachment and entry are dependent on αVβ3 integrin localized to specific cell surface microdomains and do not correlate with the presence of heparan sulfate. Virology 2014; 464-465:118-133. [PMID: 25063885 DOI: 10.1016/j.virol.2014.06.035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/02/2014] [Accepted: 06/27/2014] [Indexed: 11/16/2022]
Abstract
Cellular receptors for KSHV attachment and entry were characterized using tyramide signal amplification (TSA)-enhanced confocal microscopy. Integrins αVβ3, αVβ5 and α3β1 were detected on essentially all the actin-based cell surface microdomains that initially bind KSHV, while the presence of CD98 and heparan sulfate (HS), the putative attachment receptor, was more variable. KSHV bound to the same cell surface microdomains with and without HS indicating that initial attachment of KSHV is not dependent on HS and that receptors other than HS can mediate attachment. A human salivary gland (HSG) epithelial line was identified, which lacks αVβ3 but expresses high levels of HS, α3β1 and other putative KSHV receptors. These cells were resistant to KSHV binding and infection. Reconstitution of cell surface αVβ3 rendered HSG cells highly susceptible to KSHV infection, demonstrating a critical role for αVβ3 in the binding and entry of KSHV that is not shared with other proposed receptors.
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Affiliation(s)
- H Jacques Garrigues
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA.
| | - Laura K DeMaster
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | - Yelena E Rubinchikova
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA.
| | - Timothy M Rose
- Seattle Children׳s Research Institute, 1900 Ninth Avenue, 8th Floor, Seattle, WA 98101, USA; Department of Pediatrics, University of Washington, Seattle, WA 98195, USA.
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Poettler M, Unseld M, Braemswig K, Haitel A, Zielinski CC, Prager GW. CD98hc (SLC3A2) drives integrin-dependent renal cancer cell behavior. Mol Cancer 2013; 12:169. [PMID: 24359579 PMCID: PMC3879186 DOI: 10.1186/1476-4598-12-169] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 11/29/2013] [Indexed: 11/30/2022] Open
Abstract
Background Overexpression of CD98hc (SLC3A2) occurs in a variety of cancers and is suspected to contribute to tumor growth. CD98, a heterodimeric transmembrane protein, physically associates with certain integrin β subunit cytoplasmic domains via its heavy chain, CD98hc. CD98hc regulates adhesion-induced intracellular signal transduction via integrins, thereby, affecting cell proliferation and clonal expansion. Disruption of CD98hc led to embryonic lethality in mice (E 3.5 and E 9.5) and CD98hc −/− embryonic stem cell transplantation failed to form teratomas, while CD98hc over-expression in somatic cells resulted in anchorage-independent growth. However, it is unclear whether interference with CD98hc expression tumor cell behavior. Methods Renal cell cancer cell lines have been used to determine the effect of CD98hc expression on cancer cell behavior using cell adhesion, cell trans-migration and cell spreading assays. Flow cytometric analysis was performed to study the rate of apoptosis after detachment or serum starvation. shRNA-lentiviral constructs were used to stably knockdown or reconstitute full length or mutated CD98hc. The role of CD98 as a promotor of tumorigenesis was evaluated using an in in vivo tumor transplantation animal model. Immunohistochemical analysis was performed to analyze cell proliferation and CD98 expression in tumors. Results This report shows that CD98hc silencing in clear cell renal cancer cells reverts certain characteristics of tumorigenesis, including cell spreading, migration, proliferation and survival in vitro, and tumor growth in vivo. Acquisition of tumorigenic characteristics in clear cell renal cancer cells occurred through the integrin binding domain of CD98hc. A CD98hc/integrin interaction was required for adhesion-induced sustained FAK phosphorylation and activation of the major downstream signaling pathways PI3k/Akt and MEK/ERK, while overexpression of a constitutive active form of FAK rescued the CD98hc deficiency. Conclusions In this study we demonstrate that loss of CD98hc blocks tumorigenic potential in renal cell cancer.
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Affiliation(s)
| | | | | | | | | | - Gerald W Prager
- Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria.
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Targeting intestinal inflammation with CD98 siRNA/PEI-loaded nanoparticles. Mol Ther 2013; 22:69-80. [PMID: 24025751 DOI: 10.1038/mt.2013.214] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 09/03/2013] [Indexed: 12/27/2022] Open
Abstract
Intestinal CD98 expression plays a crucial role in controlling homeostatic and innate immune responses in the gut. Modulation of CD98 expression in intestinal cells therefore represents a promising therapeutic strategy for the treatment and prevention of inflammatory intestinal diseases, such as inflammatory bowel disease. Here, the advantages of nanoparticles (NPs) are used, including their ability to easily pass through physiological barriers and evade phagocytosis, high loading concentration, rapid kinetics of mixing and resistance to degradation. Using physical chemistry characterizations techniques, CD98 siRNA/polyethyleneimine (PEI)-loaded NPs was characterized (diameter of ~480 nm and a zeta potential of -5.26 mV). Interestingly, CD98 siRNA can be electrostatically complexed by PEI and thus protected from RNase. In addition, CD98 siRNA/PEI-loaded NPs are nontoxic and biocompatible with intestinal cells. Oral administration of CD98/PEI-loaded NPs encapsulated in a hydrogel reduced CD98 expression in mouse colonic tissues and decreased dextran sodium sulfate-induced colitis in a mouse model. Finally, flow cytometry showed that CD98 was effectively downregulated in the intestinal epithelial cells and intestinal macrophages of treated mice. Finally, the results collectively demonstrated the therapeutic effect of "hierarchical nano-micro particles" with colon-homing capabilities and the ability to directly release "molecularly specific" CD98 siRNA in colonic cells, thereby decreasing colitis.
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Santiago-Gómez A, Barrasa JI, Olmo N, Lecona E, Burghardt H, Palacín M, Lizarbe MA, Turnay J. 4F2hc-silencing impairs tumorigenicity of HeLa cells via modulation of galectin-3 and β-catenin signaling, and MMP-2 expression. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2045-56. [PMID: 23651923 DOI: 10.1016/j.bbamcr.2013.04.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 04/29/2013] [Accepted: 04/30/2013] [Indexed: 01/17/2023]
Abstract
4F2hc is a type-II glycoprotein whose covalent-bound association with one of several described light chains yields a heterodimer mainly involved in large neutral amino acid transport. Likewise, it is well known that the heavy chain interacts with β-integrins mediating integrin-dependent events such as survival, proliferation, migration and even transformation. 4F2hc is a ubiquitous protein whose overexpression has been related to tumor development and progression. Stable silencing of 4F2hc in HeLa cells using an artificial miRNA impairs in vivo tumorigenicity and leads to an ineffective proliferation response to mitogens. 4F2hc colocalizes with β1-integrins and CD147, but this interaction does not occur in lipid rafts in HeLa cells. Moreover, silenced cells present defects in integrin- (FAK, Akt and ERK1/2) and hypoxia-dependent signaling, and reduced expression/activity of MMP-2. These alterations seem to be dependent on the inappropriate formation of CD147/4F2hc/β1-integrin heterocomplexes on the cell surface, arising when CD147 cannot interact with 4F2hc. Although extracellular galectin-3 accumulates due to the decrease in MMP-2 activity, galectin-3 signaling events are blocked due to an impaired interaction with 4F2hc, inducing an increased degradation of β-catenin. Furthermore, cell motility is compromised after protein silencing, suggesting that 4F2hc is related to tumor invasion by facilitating cell motility. Therefore, here we propose a molecular mechanism by which 4F2hc participates in tumor progression, favoring first steps of epithelial-mesenchymal transition by inhibition of β-catenin proteasomal degradation through Akt/GSK-3β signaling and enabling cell motility.
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Affiliation(s)
- Angélica Santiago-Gómez
- Departamento de Bioquímica y Biología Molecular I, Facultad de Ciencias Químicas, Universidad Complutense, 28040-Madrid, Spain
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CD98 increases renal epithelial cell proliferation by activating MAPKs. PLoS One 2012; 7:e40026. [PMID: 22768207 PMCID: PMC3386947 DOI: 10.1371/journal.pone.0040026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 05/31/2012] [Indexed: 12/22/2022] Open
Abstract
CD98 heavy chain (CD98hc) is a multifunctional transmembrane spanning scaffolding protein whose extracellular domain binds with light chain amino acid transporters (Lats) to form the heterodimeric amino acid transporters (HATs). It also interacts with β1 and β3 integrins by its transmembrane and cytoplasmic domains. This interaction is proposed to be the mechanism whereby CD98 mediates cell survival and growth via currently undefined signaling pathways. In this study, we determined whether the critical function of CD98-dependent amino acid transport also plays a role in cell proliferation and defined the signaling pathways that mediate CD98-dependent proliferation of murine renal inner medullary collecting duct (IMCD) cells. We demonstrate that downregulating CD98hc expression resulted in IMCD cell death. Utilizing overexpression studies of CD98hc mutants that either lacked a cytoplasmic tail or were unable to bind to Lats we showed that CD98 increases serum-dependent cell proliferation by a mechanism that requires the CD98hc cytoplasmic tail. We further demonstrated that CD98-dependent amino acid transport increased renal tubular epithelial cell proliferation by a mechanism that does not require the CD98hc cytoplasmic tail. Both these mechanisms of increased renal tubular epithelial cell proliferation are mediated by Erk and p38 MAPK signaling. Although increased amino transport markedly activated mTor signaling, this pathway did not alter cell proliferation. Thus, these studies demonstrate that in IMCD cells, the cytoplasmic and extracellular domains of CD98hc regulate cell proliferation by distinct mechanisms that are mediated by common MAPK signaling pathways.
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Cheng L, Chen Y, Chen L, Shen Y, Shen J, An R, Luo Q, Du J. Interactions between the ROP18 kinase and host cell proteins that aid in the parasitism of Toxoplasma gondii. Acta Trop 2012; 122:255-60. [PMID: 22365922 DOI: 10.1016/j.actatropica.2012.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 01/20/2012] [Accepted: 02/08/2012] [Indexed: 11/24/2022]
Abstract
Serine/threonine kinases secreted from rhoptry organelles are important virulence factors for Toxoplasma gondii. Among rhoptry proteins, the ROP18 kinase has been identified as a key virulence determinant mediating pathogenesis in T. gondii; however, the molecular mechanisms by which this kinase exerts its pathogenic action remain poorly understood. In this study, the interactions between the ROP18 kinase of Toxoplasma gondii and the host cell proteins were analyzed using a yeast two-hybrid technique. The cMyc-ROP18(25-251) fusion proteins expressed by pGBKT7 plasmids in AH109 yeast were bound to host cell proteins from a human fetal brain cDNA library transformed to AH109 yeast using a mating method. Using these selection procedures, we identified seven host proteins that had not previously been reported to interact with ROP18 such as DDB1, TOR1AIP1, integrin, SLC3A2, TPST2, DERL2 and OCIAD1. These host proteins are associated with DNA repair, transcriptional regulation, translation modification, protein degradation and cell adhesion. Our data strongly support the hypothesis that the secreted kinase ROP18 is involved in several complex cellular pathways for the invasion and commandeering of host functions.
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Cantor JM, Ginsberg MH. CD98 at the crossroads of adaptive immunity and cancer. J Cell Sci 2012; 125:1373-82. [PMID: 22499670 DOI: 10.1242/jcs.096040] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Adaptive immunity, a vertebrate specialization, adds memory and exquisite specificity to the basic innate immune responses present in invertebrates while conserving metabolic resources. In adaptive immunity, antigenic challenge requires extremely rapid proliferation of rare antigen-specific lymphocytes to produce large, clonally expanded effector populations that neutralize pathogens. Rapid proliferation and resulting clonal expansion are dependent on CD98, a protein whose well-conserved orthologs appear restricted to vertebrates. Thus, CD98 supports lymphocyte clonal expansion to enable protective adaptive immunity, an advantage that could account for the presence of CD98 in vertebrates. CD98 supports lymphocyte clonal expansion by amplifying integrin signals that enable proliferation and prevent apoptosis. These integrin-dependent signals can also provoke cancer development and invasion, anchorage-independence and the rapid proliferation of tumor cells. CD98 is highly expressed in many cancers and contributes to formation of tumors in experimental models. Strikingly, vertebrates, which possess highly conserved CD98 proteins, CD98-binding integrins and adaptive immunity, also display propensity towards invasive and metastatic tumors. In this Commentary, we review the roles of CD98 in lymphocyte biology and cancer. We suggest that the CD98 amplification of integrin signaling in adaptive immunity provides survival benefits to vertebrates, which, in turn, bear the price of increased susceptibility to cancer.
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Affiliation(s)
- Joseph M Cantor
- Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA
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Homeostatic and innate immune responses: role of the transmembrane glycoprotein CD98. Cell Mol Life Sci 2012; 69:3015-26. [PMID: 22460579 DOI: 10.1007/s00018-012-0963-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2011] [Revised: 02/14/2012] [Accepted: 03/12/2012] [Indexed: 12/11/2022]
Abstract
The transmembrane glycoprotein CD98 is a potential regulator of multiple functions, including integrin signaling and amino acid transport. Abnormal expression or function of CD98 and disruption of the interactions between CD98 and its binding partners result in defects in cell homeostasis and immune responses. Indeed, expression of CD98 has been correlated with diseases such as inflammation and tumor metastasis. Modulation of CD98 expression and/or function therefore represents a promising therapeutic strategy for the treatment and prevention of such pathologies. Herein, we review the role of CD98 with focus on its functional importance in homeostasis and immune responses, which could help to better understand the pathogenesis of CD98-associated diseases.
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Tsumura H, Ito M, Li XK, Nakamura A, Ohnami N, Fujimoto JI, Komada H, Ito Y. The role of CD98hc in mouse macrophage functions. Cell Immunol 2012; 276:128-34. [DOI: 10.1016/j.cellimm.2012.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 04/24/2012] [Accepted: 04/25/2012] [Indexed: 01/23/2023]
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The lipid raft-associated protein CD98 is required for vaccinia virus endocytosis. J Virol 2012; 86:4868-82. [PMID: 22345471 DOI: 10.1128/jvi.06610-11] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mature vaccinia virus (vaccinia MV) infects a broad range of animals in vivo and cell cultures in vitro; however, the cellular receptors that determine vaccinia MV tropism and entry pathways are poorly characterized. Here, we performed quantitative proteomic analyses of lipid raft-associated proteins upon vaccinia MV entry into HeLa cells. We found that a type II membrane glycoprotein, CD98, is enriched in lipid rafts upon vaccinia MV infection compared to mock-infected HeLa cells. The knockdown of CD98 expression in HeLa cells significantly reduced vaccinia MV entry. Furthermore, CD98 knockout (KO) mouse embryonic fibroblasts (MEFs) also exhibited reduced vaccinia MV infectivity without affecting MV attachment to cells, suggesting a role for CD98 in the postbinding step of virus entry. Further characterization with inhibitors and dominant negative proteins that block different endocytic pathways revealed that vaccinia MV entry into MEFs occurs through a clathrin-independent, caveolin-independent, dynamin-dependent, fluid-phase endocytic pathway, implying that CD98 plays a specific role in the vaccinia MV endocytic pathway. Infections of wild-type and CD98 KO MEF cells with different strains of vaccinia MV provided further evidence that CD98 plays a specific role in MV endocytosis but not in plasma membrane fusion. Finally, different CD98-C69 chimeric proteins were expressed in CD98 KO MEFs, but none were able to reconstitute MV infectivity, suggesting that the overall structure of the CD98 protein is required for vaccinia MV endocytosis.
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Solute carrier family 3 member 2 (Slc3a2) controls yolk syncytial layer (YSL) formation by regulating microtubule networks in the zebrafish embryo. Proc Natl Acad Sci U S A 2012; 109:3371-6. [PMID: 22331904 DOI: 10.1073/pnas.1200642109] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The yolk syncytial layer (YSL) in the zebrafish embryo is a multinucleated syncytium essential for embryo development, but the molecular mechanisms underlying YSL formation remain largely unknown. Here we show that zebrafish solute carrier family 3 member 2 (Slc3a2) is expressed specifically in the YSL and that slc3a2 knockdown causes severe YSL defects including clustering of the yolk syncytial nuclei and enhanced cell fusion, accompanied by disruption of microtubule networks. Expression of a constitutively active RhoA mimics the YSL phenotypes caused by slc3a2 knockdown, whereas attenuation of RhoA or ROCK activity rescues the slc3a2-knockdown phenotypes. Furthermore, slc3a2 knockdown significantly reduces tyrosine phosphorylation of c-Src, and overexpression of a constitutively active Src restores the slc3a2-knockdown phenotypes. Our data demonstrate a signaling pathway regulating YSL formation in which Slc3a2 inhibits the RhoA/ROCK pathway via phosphorylation of c-Src to modulate YSL microtubule dynamics. This work illuminates processes at a very early stage of zebrafish embryogenesis and more generally informs the mechanism of cell dynamics during syncytium formation.
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Prager GW, Poettler M. Angiogenesis in cancer. Basic mechanisms and therapeutic advances. Hamostaseologie 2011; 32:105-14. [PMID: 21837355 DOI: 10.5482/ha-1163] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 07/18/2011] [Indexed: 12/15/2022] Open
Abstract
Etiological concepts on cancer development, malignant growth and tumour propagation have undergone a revolutionary development during recent years: Among other aspects, the discovery of angiogenesis - the growth of new blood vessels from pre-existing vasculature - as a key element in the pathogenesis of malignancy has opened an abundance of biologic insights and subsequent therapeutic options, which have led to improved prognosis in many cancers including those originating from colon, lung, breast and kidney. Thereby, targeting the major pro-angiogenic stimulus vascular endothelial growth factor (VEGF) became the focus for therapeutic interventions. However, the use of VEGF-targeting drugs has been shown to be of limited efficacy, which might lie in the fact that tumor angiogenesis is mediated by a variety of different subcellular systems. This review focuses on the basic mechanisms involved in angiogenesis, which potentially represent novel targets for pharmacological agents in the treatment of malignancies.
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Affiliation(s)
- G W Prager
- Comprehensive Cancer Center Vienna, Department of Medicine I, Medical University of Vienna, Austria.
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CD98hc (SLC3A2) is a key regulator of keratinocyte adhesion. J Dermatol Sci 2011; 61:169-79. [PMID: 21282044 DOI: 10.1016/j.jdermsci.2010.12.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 12/21/2010] [Accepted: 12/24/2010] [Indexed: 11/22/2022]
Abstract
BACKGROUND Adhesion of keratinocytes is crucial for maintaining the integrity of the skin, as demonstrated by the number of dermatological disorders of genetic origin that are associated with a defect of basal keratinocyte adhesion. Integrins are the main component of the molecular networks involved in this phenomenon, but there are many others. In a recent description of proteins associated to caveolae at the plasma membrane of human basal epidermal cells, we demonstrated that CD98hc is localized with β1 integrin. OBJECTIVES We investigated the CD98hc proteins interactions and the role of CD98hc in keratinocyte adhesion. METHODS CD98hc protein interaction was identified following co-immunoprecipitation and proteomic analysis using LTQ-FT mass spectrometer. Extinction of CD98hc gene expression using specific short hairpin RNA or over-expression of CD98hc lacking the β1 integrin binding site was used to evaluate the role of this protein in keratinocyte fate. RESULTS We show that CD98hc forms molecular complexes with β1 and β4 integrins in primary human keratinocytes and, using immunofluorescence, that these complexes are localized at the plasma membrane, in keeping with a role in adhesion. We confirmed that this protein is a key player of keratinocyte adhesion because in absence of interaction between CD98hc and integrins, β1 integrin failed to translocate from the cytoplasm to the plasma membrane and keratinocytes expressed epidermal differentiation markers. CONCLUSIONS All these data strongly suggested that CD98hc is involved in integrin trafficking and by consequence, in keratinocyte adhesion and differentiation.
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Fogelstrand P, Féral CC, Zargham R, Ginsberg MH. Dependence of proliferative vascular smooth muscle cells on CD98hc (4F2hc, SLC3A2). ACTA ACUST UNITED AC 2009; 206:2397-406. [PMID: 19841087 PMCID: PMC2768859 DOI: 10.1084/jem.20082845] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Activation of vascular smooth muscle cells (VSMCs) to migrate and proliferate is essential for the formation of intimal hyperplasia. Hence, selectively targeting activated VSMCs is a potential strategy against vaso-occlusive disorders such as in-stent restenosis, vein-graft stenosis, and transplant vasculopathy. We show that CD98 heavy chain (CD98hc) is markedly up-regulated in neointimal and cultured VSMCs, and that activated but not quiescent VSMCs require CD98hc for survival. CD98hc mediates integrin signaling and localizes amino acid transporters to the plasma membrane. SMC-specific deletion of CD98hc did not affect normal vessel morphology, indicating that CD98hc was not required for the maintenance of resident quiescent VSMCs; however, CD98hc deletion reduced intimal hyperplasia after arterial injury. Ex vivo and in vitro, loss of CD98hc suppressed proliferation and induced apoptosis in VSMCs. Furthermore, reconstitution with CD98hc mutants showed that CD98hc interaction with integrins was necessary for the survival of VSMCs. These studies establish the importance of CD98hc in VSMC proliferation and survival. Furthermore, loss of CD98hc was selectively deleterious to activated VSMCs while sparing resident quiescent VSMCs, suggesting that activated VSMCs are physiologically dependent on CD98hc, and hence, CD98hc is a potential therapeutic target in vaso-occlusive disorders.
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Affiliation(s)
- Per Fogelstrand
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
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Watts JC, Huo H, Bai Y, Ehsani S, Won AH, Shi T, Daude N, Lau A, Young R, Xu L, Carlson GA, Williams D, Westaway D, Schmitt-Ulms G. Interactome analyses identify ties of PrP and its mammalian paralogs to oligomannosidic N-glycans and endoplasmic reticulum-derived chaperones. PLoS Pathog 2009; 5:e1000608. [PMID: 19798432 PMCID: PMC2749441 DOI: 10.1371/journal.ppat.1000608] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Accepted: 09/08/2009] [Indexed: 02/04/2023] Open
Abstract
The physiological environment which hosts the conformational conversion of the cellular prion protein (PrP(C)) to disease-associated isoforms has remained enigmatic. A quantitative investigation of the PrP(C) interactome was conducted in a cell culture model permissive to prion replication. To facilitate recognition of relevant interactors, the study was extended to Doppel (Prnd) and Shadoo (Sprn), two mammalian PrP(C) paralogs. Interestingly, this work not only established a similar physiological environment for the three prion protein family members in neuroblastoma cells, but also suggested direct interactions amongst them. Furthermore, multiple interactions between PrP(C) and the neural cell adhesion molecule, the laminin receptor precursor, Na/K ATPases and protein disulfide isomerases (PDI) were confirmed, thereby reconciling previously separate findings. Subsequent validation experiments established that interactions of PrP(C) with PDIs may extend beyond the endoplasmic reticulum and may play a hitherto unrecognized role in the accumulation of PrP(Sc). A simple hypothesis is presented which accounts for the majority of interactions observed in uninfected cells and suggests that PrP(C) organizes its molecular environment on account of its ability to bind to adhesion molecules harboring immunoglobulin-like domains, which in turn recognize oligomannose-bearing membrane proteins.
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Affiliation(s)
- Joel C. Watts
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Hairu Huo
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Yu Bai
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Sepehr Ehsani
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Amy Hye Won
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Tujin Shi
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
| | - Nathalie Daude
- Alberta Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Agnes Lau
- Alberta Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Rebecca Young
- McLaughlin Research Institute, Great Falls, Montana, United States of America
| | - Lei Xu
- McLaughlin Research Institute, Great Falls, Montana, United States of America
| | - George A. Carlson
- McLaughlin Research Institute, Great Falls, Montana, United States of America
| | - David Williams
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - David Westaway
- Alberta Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Gerold Schmitt-Ulms
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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Drosophila expresses a CD98 transporter with an evolutionarily conserved structure and amino acid-transport properties. Biochem J 2009; 420:363-72. [PMID: 19335336 DOI: 10.1042/bj20082198] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mammalian CD98 heterodimeric amino acid transporters consist of a promiscuous single-pass transmembrane glycoprotein, CD98hc (CD98 heavy chain), and one of six multipass transmembrane proteins or 'light chains'. The heterodimeric complexes of CD98hc and the light chains LAT1 (L-type amino acid transporter 1) or LAT2 specifically promote sodium-independent System L exchange of neutral amino acids, including leucine. CD98hc is also implicated in other processes, including cell fusion, cell adhesion and activation of TOR (target of rapamycin) signalling. Surprisingly, recent reports suggested that insects lack a membrane-bound CD98hc, but in the present study we show that Drosophila CG2791 encodes a functional CD98hc orthologue with conservation in intracellular, transmembrane and extracellular domains. We demonstrate by RNA-interference knockdown in Drosophila Schneider cells that CG2791 and two Drosophila homologues of the mammalian CD98 light chains, Mnd (Minidiscs) and JhI-21, are required for normal levels of System L transport. Furthermore, we show that System L activity is increased by methoprene, an analogue of the developmentally regulated endocrine hormone juvenile hormone, an effect that is potentially mediated by elevated Mnd expression. Co-expression of CG2791 and JhI-21, but not CG2791 and Mnd, in Xenopus oocytes mediates System L transport. Finally, mapping of conserved sequences on to the recently determined crystal structure of the human CD98hc extracellular domain highlights two conserved exposed hydrophobic patches at either end of the domain that are potential protein-protein-interaction surfaces. Therefore our results not only show that there is functional conservation of CD98hc System L transporters in flies, but also provide new insights into the structure, functions and regulation of heterodimeric amino acid transporters.
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Prager GW, Poettler M, Schmidinger M, Mazal PR, Susani M, Zielinski CC, Haitel A. CD98hc (SLC3A2), a novel marker in renal cell cancer. Eur J Clin Invest 2009; 39:304-10. [PMID: 19292886 DOI: 10.1111/j.1365-2362.2009.02096.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND In a variety of malignant diseases, molecular targeting represents a therapeutic option, whereby, when compared with chemotherapy, fewer side effects are thought to be expected. Especially in renal cell cancer (RCC), tyrosine kinase-inhibitors have been established as useful and highly effective therapy. However, tyrosine kinase-inhibitors currently approved for RCC treatment lack single molecule specificity and bear a variety of side effects of the gastro-intestinal tract, skin, heart and haematopoietic system. Therefore, the identification of novel cell surface markers is sought, which might lead to novel diagnostic and therapeutic strategies in cancer. MATERIAL AND METHODS Paraffin-embedded RCCs from a well characterized tissue bank were immunohistochemically quantified for embryonic transmembrane antigen CD98hc (SLC3A2) expression and semi-quantitative analyses were correlated with subtype or grade of differentiation. RESULTS We found increased CD98hc expression in different types of malign RCCs, among them clear cell (cc)RCC, papillary (p)RCC and chromophobe (ch)RCC, but lack of expression in the benign renal oncocytoma. Thereby, the extent of CD98hc expression directly complies with grade of malignancy. Furthermore, the more malignant type II pRCC significantly higher expressed CD98hc than the less malignant and more differentiated type I pRCC (type II 83.34%, type I 4.76% CD98hc positive, P < 0.00001; n = 51). The established marker for type I pRCC, Cytokreatin 7, showed 95.24% expression in type I and 26.67% expression in type II pRCC (P < 0.00001, n = 51). CONCLUSIONS From these data, we conclude that CD98hc is expressed in RCCs, whereby the extent of expression is likely to correlate directly with grade of malignancy. In pRCCs, CD98hc might represent a novel and reliable marker for type II pRCC.
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Affiliation(s)
- G W Prager
- Department of Medicine I, Medical University of Vienna, Vienna, Austria.
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