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Gröner B, Hoffmann C, Endepols H, Urusova EA, Brugger M, Neumaier F, Timmer M, Neumaier B, Zlatopolskiy BD. Radiosynthesis and Preclinical Evaluation of m-[ 18F]FET and [ 18F]FET-OMe as Novel [ 18F]FET Analogs for Brain Tumor Imaging. Mol Pharm 2024; 21:2795-2812. [PMID: 38747353 DOI: 10.1021/acs.molpharmaceut.3c01215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
O-([18F]Fluoroethyl)-l-tyrosine ([18F]FET) is actively transported into the brain and cancer cells by LAT1 and possibly other amino acid transporters, which enables brain tumor imaging by positron emission tomography (PET). However, tumor delivery of this probe in the presence of competing amino acids may be limited by a relatively low affinity for LAT1. The aim of the present work was to evaluate the meta-substituted [18F]FET analog m-[18F]FET and the methyl ester [18F]FET-OMe, which were designed to improve tumor delivery by altering the physicochemical, pharmacokinetic, and/or transport properties. Both tracers could be prepared with good radiochemical yields of 41-56% within 66-90 min. Preclinical evaluation with [18F]FET as a reference tracer demonstrated reduced in vitro uptake of [18F]FET-OMe by U87 glioblastoma cells and no advantage for in vivo tumor imaging. In contrast, m-[18F]FET showed significantly improved in vitro uptake and accelerated in vivo tumor accumulation in an orthotopic glioblastoma model. As such, our work identifies m-[18F]FET as a promising alternative to [18F]FET for brain tumor imaging that deserves further evaluation with regard to its transport properties and in vivo biodistribution.
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Affiliation(s)
- Benedikt Gröner
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Chris Hoffmann
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Heike Endepols
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
- Faculty of Medicine and University Hospital Cologne, Department of Nuclear Medicine, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Elizaveta A Urusova
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Melanie Brugger
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
| | - Felix Neumaier
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Marco Timmer
- Faculty of Medicine and University Hospital Cologne, Center for Neurosurgery, Department of General Neurosurgery, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Bernd Neumaier
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Boris D Zlatopolskiy
- Forschungszentrum Jülich GmbH, Nuclear Chemistry (INM-5), Institute of Neuroscience and Medicine, Wilhelm-Johnen-Straße, Jülich 52428, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging, University of Cologne, Kerpener Straße 62, Cologne 50937, Germany
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2
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Järvinen J, Pulkkinen H, Rautio J, Timonen JM. Amino Acid-Based Boron Carriers in Boron Neutron Capture Therapy (BNCT). Pharmaceutics 2023; 15:2663. [PMID: 38140004 PMCID: PMC10748186 DOI: 10.3390/pharmaceutics15122663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 11/18/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Interest in the design of boronated amino acids has emerged, partly due to the utilization of boronophenylalanine (BPA), one of the two agents employed in clinical Boron Neutron Capture Therapy (BNCT). The boronated amino acids synthesized thus far for BNCT investigations can be classified into two categories based on the source of boron: boronic acids or carboranes. Amino acid-based boron carriers, employed in the context of BNCT treatment, demonstrate significant potential in the treatment of challenging tumors, such as those located in the brain. This review aims to shed light on the developmental journey and challenges encountered over the years in the field of amino acid-based boron delivery compound development. The primary focus centers on the utilization of the large amino acid transporter 1 (LAT1) as a target for boron carriers in BNCT. The development of efficient carriers remains a critical objective, addressing challenges related to tumor specificity, effective boron delivery, and rapid clearance from normal tissue and blood. LAT1 presents an intriguing and promising target for boron delivery, given its numerous characteristics that make it well suited for drug delivery into tumor tissues, particularly in the case of brain tumors.
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Affiliation(s)
- Juulia Järvinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70211 Kuopio, Finland
| | - Herkko Pulkkinen
- Department of Technical Physics, Faculty of Science, Forestry and Technology, University of Eastern Finland, 70211 Kuopio, Finland
| | - Jarkko Rautio
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70211 Kuopio, Finland
| | - Juri M. Timonen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70211 Kuopio, Finland
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, 00014 Helsinki, Finland
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3
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Guo H, Xu W, Nomoto T, Kanamori K, Voon YM, Honda Y, Yamada N, Takemoto H, Matsui M, Nishiyama N. Polymeric ligands comprising sulfur-containing amino acids for targeting tumor-associated amino acid transporters. Biomaterials 2023; 293:121987. [PMID: 36584445 DOI: 10.1016/j.biomaterials.2022.121987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 12/16/2022] [Accepted: 12/23/2022] [Indexed: 12/25/2022]
Abstract
Various cancer cells overexpress L-type amino acid transporter 1 (LAT1) to take up a large number of neutral amino acids such as phenylalanine and methionine, and LAT1 transporter should be a promising target for cancer diagnosis and therapy. However, only a few studies reported drug delivery systems targeting LAT1 probably due to limited knowledge about the interaction between LAT1 and its substrate. Here, we developed polymers having methionine (Met)- or cysteine (Cys)-like structures on their side chains to examine their affinity with LAT1. While both the Met- and Cys-modified polymers exhibited efficient cellular uptake selectively in cancer cells, the Met-modified polymers exhibited higher cellular uptake efficiency in an LAT1-selective manner than the Cys-modified polymers. In the in vivo study, the intraperitoneally injected Met-modified polymers showed appreciable tumor-selective accumulation in the peritoneal dissemination model, and importantly, Met-modified polymers conjugated with photosensitizers exhibited significant therapeutic effects upon photoirradiation with reduced photochemical damage to normal organs. Our results may provide important knowledge about the polymer-LAT1 interaction, and the Met-modified polymers should offer a new concept for designing LAT1-targeting drug delivery systems.
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Affiliation(s)
- Haochen Guo
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Wen Xu
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Takahiro Nomoto
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan.
| | - Kaito Kanamori
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Yan Ming Voon
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Yuto Honda
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Naoki Yamada
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Hiroyasu Takemoto
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Makoto Matsui
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Nobuhiro Nishiyama
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; Innovation Center of Nanomedicine (iCONM), Kawasaki Institute of Industrial Promotion, 3-25-14 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa, 210-0821, Japan.
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Gyimesi G, Hediger MA. Transporter-Mediated Drug Delivery. Molecules 2023; 28:molecules28031151. [PMID: 36770817 PMCID: PMC9919865 DOI: 10.3390/molecules28031151] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/12/2023] [Accepted: 01/18/2023] [Indexed: 01/27/2023] Open
Abstract
Transmembrane transport of small organic and inorganic molecules is one of the cornerstones of cellular metabolism. Among transmembrane transporters, solute carrier (SLC) proteins form the largest, albeit very diverse, superfamily with over 400 members. It was recognized early on that xenobiotics can directly interact with SLCs and that this interaction can fundamentally determine their efficacy, including bioavailability and intertissue distribution. Apart from the well-established prodrug strategy, the chemical ligation of transporter substrates to nanoparticles of various chemical compositions has recently been used as a means to enhance their targeting and absorption. In this review, we summarize efforts in drug design exploiting interactions with specific SLC transporters to optimize their therapeutic effects. Furthermore, we describe current and future challenges as well as new directions for the advanced development of therapeutics that target SLC transporters.
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5
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Bahrami K, Järvinen J, Laitinen T, Reinisalo M, Honkakoski P, Poso A, Huttunen KM, Rautio J. Structural Features Affecting the Interactions and Transportability of LAT1-Targeted Phenylalanine Drug Conjugates. Mol Pharm 2023; 20:206-218. [PMID: 36394563 PMCID: PMC9811466 DOI: 10.1021/acs.molpharmaceut.2c00594] [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] [Indexed: 11/18/2022]
Abstract
L-type amino acid transporter 1 (LAT1) transfers essential amino acids across cell membranes. Owing to its predominant expression in the blood-brain barrier and tumor cells, LAT1 has been exploited for drug delivery and targeting to the central nervous system (CNS) and various cancers. Although the interactions of amino acids and their mimicking compounds with LAT1 have been extensively investigated, the specific structural features for an optimal drug scaffold have not yet been determined. Here, we evaluated a series of LAT1-targeted drug-phenylalanine conjugates (ligands) by determining their uptake rates by in vitro studies and investigating their interaction with LAT1 via induced-fit docking. Combining the experimental and computational data, we concluded that although LAT1 can accommodate various types of structures, smaller compounds are preferred. As the ligand size increased, its flexibility became more crucial in determining the compound's transportability and interactions. Compounds with linear or planar structures exhibited reduced uptake; those with rigid lipophilic structures lacked interactions and likely utilized other transport mechanisms for cellular entry. Introducing polar groups between aromatic structures enhanced interactions. Interestingly, compounds with a carbamate bond in the aromatic ring's para-position displayed very good transport efficiencies for the larger compounds. Compared to the ester bond, the corresponding amide bond had superior hydrogen bond acceptor properties and increased interactions. A reverse amide bond was less favorable than a direct amide bond for interactions with LAT1. The present information can be applied broadly to design appropriate CNS or antineoplastic drug candidates with a prodrug strategy and to discover novel LAT1 inhibitors used either as direct or adjuvant cancer therapy.
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6
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Hutchinson K, Silva DB, Bohlke J, Clausen C, Thomas AA, Bonomi M, Schlessinger A. Describing inhibitor specificity for the amino acid transporter LAT1 from metainference simulations. Biophys J 2022; 121:4476-4491. [PMID: 36369754 PMCID: PMC9748366 DOI: 10.1016/j.bpj.2022.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 09/09/2022] [Accepted: 10/31/2022] [Indexed: 11/13/2022] Open
Abstract
The human L-type amino acid transporter 1 (LAT1; SLC7A5) is a membrane transporter of amino acids, thyroid hormones, and drugs such as the Parkinson's disease drug levodopa (L-Dopa). LAT1 is found in the blood-brain barrier, testis, bone marrow, and placenta, and its dysregulation has been associated with various neurological diseases, such as autism and epilepsy, as well as cancer. In this study, we combine metainference molecular dynamics simulations, molecular docking, and experimental testing, to characterize LAT1-inhibitor interactions. We first conducted a series of molecular docking experiments to identify the most relevant interactions between LAT1's substrate-binding site and ligands, including both inhibitors and substrates. We then performed metainference molecular dynamics simulations using cryoelectron microscopy structures in different conformations of LAT1 with the electron density map as a spatial restraint, to explore the inherent heterogeneity in the structures. We analyzed the LAT1 substrate-binding site to map important LAT1-ligand interactions as well as newly described druggable pockets. Finally, this analysis guided the discovery of previously unknown LAT1 ligands using virtual screening and cellular uptake experiments. Our results improve our understanding of LAT1-inhibitor recognition, providing a framework for rational design of future lead compounds targeting this key drug target.
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Affiliation(s)
- Keino Hutchinson
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Dina Buitrago Silva
- Department of Bioengineering and Therapeutic Sciences University of California, San Francisco, San Francisco, California
| | - Joshua Bohlke
- Department of Chemistry, University of Nebraska at Kearney, Kearney, Nebraska
| | - Chase Clausen
- Department of Chemistry, University of Nebraska at Kearney, Kearney, Nebraska
| | - Allen A Thomas
- Department of Chemistry, University of Nebraska at Kearney, Kearney, Nebraska
| | - Massimiliano Bonomi
- Department of Structural Biology and Chemistry, Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Paris, France.
| | - Avner Schlessinger
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York.
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7
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Khavinson V, Linkova N, Kozhevnikova E, Dyatlova A, Petukhov M. Transport of Biologically Active Ultrashort Peptides Using POT and LAT Carriers. Int J Mol Sci 2022; 23:ijms23147733. [PMID: 35887081 PMCID: PMC9323678 DOI: 10.3390/ijms23147733] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 01/27/2023] Open
Abstract
Ultrashort peptides (USPs), consisting of 2–7 amino-acid residues, are a group of signaling molecules that regulate gene expression and protein synthesis under normal conditions in various diseases and ageing. USPs serve as a basis for the development of drugs with a targeted mechanism of action. The purpose of this review is to systematize the available data on USP transport involving POT and LAT transporters in various organs and tissues under normal, pathological and ageing conditions. The carriers of the POT family (PEPT1, PEPT2, PHT1, PHT2) transport predominantly di- and tripeptides into the cell. Methods of molecular modeling and physicochemistry have demonstrated the ability of LAT1 to transfer not only amino acids but also some di- and tripeptides into the cell and out of it. LAT1 and 2 are involved in the regulation of the antioxidant, endocrine, immune and nervous systems’ functions. Analysis of the above data allows us to conclude that, depending on their structure, di- and tripeptides can be transported into the cells of various tissues by POT and LAT transporters. This mechanism is likely to underlie the tissue specificity of peptides, their geroprotective action and effectiveness in the case of neuroimmunoendocrine system disorders.
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Affiliation(s)
- Vladimir Khavinson
- Department of Biogerontology, Saint Petersburg Institute of Bioregulation and Gerontology, 197110 Saint Petersburg, Russia; (N.L.); (E.K.); (A.D.)
- Group of Peptide Regulation of Aging, Pavlov Institute of Physiology of Russian Academy of Sciences, 199034 Saint Petersburg, Russia
- Correspondence: or ; Tel.: +7-(921)-9110800
| | - Natalia Linkova
- Department of Biogerontology, Saint Petersburg Institute of Bioregulation and Gerontology, 197110 Saint Petersburg, Russia; (N.L.); (E.K.); (A.D.)
- The Laboratory “Problems of Aging”, Belgorod National Research University, 308015 Belgorod, Russia
| | - Ekaterina Kozhevnikova
- Department of Biogerontology, Saint Petersburg Institute of Bioregulation and Gerontology, 197110 Saint Petersburg, Russia; (N.L.); (E.K.); (A.D.)
| | - Anastasiia Dyatlova
- Department of Biogerontology, Saint Petersburg Institute of Bioregulation and Gerontology, 197110 Saint Petersburg, Russia; (N.L.); (E.K.); (A.D.)
| | - Mikhael Petukhov
- Petersburg Nuclear Physics Institute Named after B.P. Konstantinov, NRC “Kurchatov Institute”, 188300 Gatchina, Russia;
- Peter the Great St. Petersburg Group of Biophysics, Higher Engineering and Technical School, Peter the Great St. Petersburg Polytechnic University, 195251 Saint Petersburg, Russia
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8
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Huttunen KM, Terasaki T, Urtti A, Montaser AB, Uchida Y. Pharmacoproteomics of Brain Barrier Transporters and Substrate Design for the Brain Targeted Drug Delivery. Pharm Res 2022; 39:1363-1392. [PMID: 35257288 PMCID: PMC9246989 DOI: 10.1007/s11095-022-03193-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/08/2022] [Indexed: 12/12/2022]
Abstract
One of the major reasons why central nervous system (CNS)-drug development has been challenging in the past, is the barriers that prevent substances entering from the blood circulation into the brain. These barriers include the blood-brain barrier (BBB), blood-spinal cord barrier (BSCB), blood-cerebrospinal fluid barrier (BCSFB), and blood-arachnoid barrier (BAB), and they differ from each other in their transporter protein expression and function as well as among the species. The quantitative expression profiles of the transporters in the CNS-barriers have been recently revealed, and in this review, it is described how they affect the pharmacokinetics of compounds and how these expression differences can be taken into account in the prediction of brain drug disposition in humans, an approach called pharmacoproteomics. In recent years, also structural biology and computational resources have progressed remarkably, enabling a detailed understanding of the dynamic processes of transporters. Molecular dynamics simulations (MDS) are currently used commonly to reveal the conformational changes of the transporters and to find the interactions between the substrates and the protein during the binding, translocation in the transporter cavity, and release of the substrate on the other side of the membrane. The computational advancements have also aided in the rational design of transporter-utilizing compounds, including prodrugs that can be actively transported without losing potency towards the pharmacological target. In this review, the state-of-art of these approaches will be also discussed to give insights into the transporter-mediated drug delivery to the CNS.
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Affiliation(s)
- Kristiina M Huttunen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Tetsuya Terasaki
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Arto Urtti
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Ahmed B Montaser
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Yasuo Uchida
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan
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9
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Huttunen J, Agami M, Tampio J, Montaser AB, Huttunen KM. Comparison of Experimental Strategies to Study l-Type Amino Acid Transporter 1 (LAT1) Utilization by Ligands. Molecules 2021; 27:molecules27010037. [PMID: 35011270 PMCID: PMC8746705 DOI: 10.3390/molecules27010037] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 01/08/2023] Open
Abstract
l-Type amino acid transporter 1 (LAT1), expressed abundantly in the brain and placenta and overexpressed in several cancer cell types, has gained a lot of interest in drug research and development, as it can be utilized for brain-targeted drug delivery, as well as inhibiting the essential amino acid supply to cancer cells. The structure of LAT1 is today very well-known and the interactions of ligands at the binding site of LAT1 can be modeled and explained. However, less is known of LAT1′s life cycle within the cells. Moreover, the functionality of LAT1 can be measured by several different methods, which may vary between the laboratories and make the comparison of the results challenging. In the present study, the usefulness of indirect cis-inhibition methods and direct cellular uptake methods and their variations to interpret the interactions of LAT1-ligands were evaluated. Moreover, this study also highlights the importance of understanding the intracellular kinetics of LAT1-ligands, and how they can affect the regular function of LAT1 in critical tissues, such as the brain. Hence, it is discussed herein how the selected methodology influences the outcome and created knowledge of LAT1-utilizing compounds.
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10
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Pinheiro RGR, Coutinho AJ, Pinheiro M, Neves AR. Nanoparticles for Targeted Brain Drug Delivery: What Do We Know? Int J Mol Sci 2021; 22:ijms222111654. [PMID: 34769082 PMCID: PMC8584083 DOI: 10.3390/ijms222111654] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/18/2021] [Accepted: 10/25/2021] [Indexed: 12/26/2022] Open
Abstract
The blood-brain barrier (BBB) is a barrier that separates the blood from the brain tissue and possesses unique characteristics that make the delivery of drugs to the brain a great challenge. To achieve this purpose, it is necessary to design strategies to allow BBB passage, in order to reach the brain and target the desired anatomic region. The use of nanomedicine has great potential to overcome this problem, since one can modify nanoparticles with strategic molecules that can interact with the BBB and induce uptake through the brain endothelial cells and consequently reach the brain tissue. This review addresses the potential of nanomedicines to treat neurological diseases by using nanoparticles specially developed to cross the BBB.
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Affiliation(s)
- Rúben G. R. Pinheiro
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Ana Joyce Coutinho
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Marina Pinheiro
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Ana Rute Neves
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
- CQM—Centro de Química da Madeira, Campus da Penteada, Universidade da Madeira, 9020-105 Funchal, Portugal
- Correspondence:
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11
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Targeting Systems to the Brain Obtained by Merging Prodrugs, Nanoparticles, and Nasal Administration. Pharmaceutics 2021; 13:pharmaceutics13081144. [PMID: 34452105 PMCID: PMC8399330 DOI: 10.3390/pharmaceutics13081144] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/13/2021] [Accepted: 07/23/2021] [Indexed: 01/27/2023] Open
Abstract
About 40 years ago the lipidization of hydrophilic drugs was proposed to induce their brain targeting by transforming them into lipophilic prodrugs. Unfortunately, lipidization often transforms a hydrophilic neuroactive agent into an active efflux transporter (AET) substrate, with consequent rejection from the brain after permeation across the blood brain barrier (BBB). Currently, the prodrug approach has greatly evolved in comparison to lipidization. This review describes the evolution of the prodrug approach for brain targeting considering the design of prodrugs as active influx substrates or molecules able to inhibit or elude AETs. Moreover, the prodrug approach appears strategic in optimization of the encapsulation of neuroactive drugs in nanoparticulate systems that can be designed to induce their receptor-mediated transport (RMT) across the BBB by appropriate decorations on their surface. Nasal administration is described as a valuable alternative to obtain the brain targeting of drugs, evidencing that the prodrug approach can allow the optimization of micro or nanoparticulate nasal formulations of neuroactive agents in order to obtain this goal. Furthermore, nasal administration is also proposed for prodrugs characterized by peripheral instability but potentially able to induce their targeting inside cells of the brain.
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Kärkkäinen J, Laitinen T, Markowicz-Piasecka M, Montaser A, Lehtonen M, Rautio J, Gynther M, Poso A, Huttunen KM. Molecular characteristics supporting l-Type amino acid transporter 1 (LAT1)-mediated translocation. Bioorg Chem 2021; 112:104921. [PMID: 33933805 DOI: 10.1016/j.bioorg.2021.104921] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/21/2021] [Accepted: 02/23/2021] [Indexed: 01/02/2023]
Abstract
l-Type amino acid transporter 1 (LAT1) is an interesting protein due to its peculiar expression profile. It can be utilized not only as a carrier for improved or targeted drug delivery, e.g., into the brain but also as a target protein by which amino acid supply can be restricted, e.g., from the cancer cells. The recognition and binding processes of LAT1-ligands, such as amino acids and clinically used small molecules, including l-dopa, gabapentin, and melphalan, are today well-known. Binding to LAT1 is crucial, particularly when designing the LAT1-inhibitors. However, it will not guarantee effective translocation across the cell membrane via LAT1, which is a definite requirement for LAT1-substrates, such as drugs that elicit their pharmacological effects inside the cells. Therefore, in the present study, the accumulation of known LAT1-utilizing compounds into the selected LAT1-expressing cancer cells (MCF-7) was explored experimentally over a time period. The differences found among the transport efficiency and affinity of the studied compounds for LAT1 were subsequently explained by docking the ligands into the human LAT1 model (based on the recent cryo-electron microscopy structure). Thus, the findings of this study clarify the favorable structural requirements of the size, shape, and polarity of the ligands that support the translocation and effective transport across the cell membrane via LAT1. This knowledge can be applied in future drug design to attain improved or targeted drug delivery and hence, successful LAT1-utilizing drugs with increased therapeutic effects.
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Affiliation(s)
- Jussi Kärkkäinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; Department of Pharmacy, Kuopio University Hospital, Finland, P.O. Box 100, FI-70029, KYS, Kuopio, Finland
| | - Tuomo Laitinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Magdalena Markowicz-Piasecka
- Laboratory of Bioanalysis, Department of Pharmaceutical Chemistry Drug Analysis and Radiopharmacy, Medical University of Lodz, Lodz, Poland
| | - Ahmed Montaser
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Marko Lehtonen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Jarkko Rautio
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Mikko Gynther
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Antti Poso
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Kristiina M Huttunen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland.
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13
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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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Venteicher B, Merklin K, Ngo HX, Chien HC, Hutchinson K, Campbell J, Way H, Griffith J, Alvarado C, Chandra S, Hill E, Schlessinger A, Thomas AA. The Effects of Prodrug Size and a Carbonyl Linker on l-Type Amino Acid Transporter 1-Targeted Cellular and Brain Uptake. ChemMedChem 2020; 16:869-880. [PMID: 33230949 DOI: 10.1002/cmdc.202000824] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/23/2020] [Indexed: 11/08/2022]
Abstract
The l-type amino acid transporter 1 (LAT1, SLC7A5) imports dietary amino acids and amino acid drugs (e. g., l-DOPA) into the brain, and plays a role in cancer metabolism. Though there have been numerous reports of LAT1-targeted amino acid-drug conjugates (prodrugs), identifying the structural determinants to enhance substrate activity has been challenging. In this work, we investigated the position and orientation of a carbonyl group in linking hydrophobic moieties including the anti-inflammatory drug ketoprofen to l-tyrosine and l-phenylalanine. We found that esters of meta-carboxyl l-phenylalanine had better LAT1 transport rates than the corresponding acylated l-tyrosine analogues. However, as the size of the hydrophobic moiety increased, we observed a decrease in LAT1 transport rate with a concomitant increase in potency of inhibition. Our results have important implications for designing amino acid prodrugs that target LAT1 at the blood-brain barrier or on cancer cells.
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Affiliation(s)
- Brooklynn Venteicher
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Kasey Merklin
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Huy X Ngo
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, 1550 4th St, Rm RH581, San Francisco, CA 94143, USA
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, 1550 4th St, Rm RH581, San Francisco, CA 94143, USA
| | - Keino Hutchinson
- Department of Pharmacological Sciences, Icahn School of Medicine at Mt. Sinai, 1468 Madison Ave, Annenberg Building Floor 19, New York, NY 10029, USA
| | - Jerome Campbell
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Hannah Way
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Joseph Griffith
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Cesar Alvarado
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Surabhi Chandra
- Department of Biology, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
| | - Evan Hill
- Department of Psychology, University of Nebraska, at Kearney 2507 11th Ave, Copeland Hall, Kearney, NE, 68849, (USA)
| | - Avner Schlessinger
- Department of Pharmacological Sciences, Icahn School of Medicine at Mt. Sinai, 1468 Madison Ave, Annenberg Building Floor 19, New York, NY 10029, USA
| | - Allen A Thomas
- Department of Chemistry, University of Nebraska at Kearney, 2401 11th Ave, Bruner Hall of Science, Kearney, NE 68849, USA
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15
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Puris E, Gynther M, Auriola S, Huttunen KM. L-Type amino acid transporter 1 as a target for drug delivery. Pharm Res 2020; 37:88. [PMID: 32377929 PMCID: PMC7203094 DOI: 10.1007/s11095-020-02826-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 04/15/2020] [Indexed: 12/13/2022]
Abstract
Our growing understanding of membrane transporters and their substrate specificity has opened a new avenue in the field of targeted drug delivery. The L-type amino acid transporter 1 (LAT1) has been one of the most extensively investigated transporters for delivering drugs across biological barriers. The transporter is predominantly expressed in cerebral cortex, blood-brain barrier, blood-retina barrier, testis, placenta, bone marrow and several types of cancer. Its physiological function is to mediate Na+ and pH independent exchange of essential amino acids: leucine, phenylalanine, etc. Several drugs and prodrugs designed as LAT1 substrates have been developed to improve targeted delivery into the brain and cancer cells. Thus, the anti-parkinsonian drug, L-Dopa, the anti-cancer drug, melphalan and the anti-epileptic drug gabapentin, all used in clinical practice, utilize LAT1 to reach their target site. These examples provide supporting evidence for the utility of the LAT1-mediated targeted delivery of the (pro)drug. This review comprehensively summarizes recent advances in LAT1-mediated targeted drug delivery. In addition, the use of LAT1 is critically evaluated and limitations of the approach are discussed.
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Affiliation(s)
- Elena Puris
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, 69120, Heidelberg, Germany.
| | - Mikko Gynther
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Seppo Auriola
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Kristiina M Huttunen
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
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16
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Pocasap P, Weerapreeyakul N, Timonen J, Järvinen J, Leppänen J, Kärkkäinen J, Rautio J. Tyrosine-Chlorambucil Conjugates Facilitate Cellular Uptake through L-Type Amino Acid Transporter 1 (LAT1) in Human Breast Cancer Cell Line MCF-7. Int J Mol Sci 2020; 21:ijms21062132. [PMID: 32244913 PMCID: PMC7139360 DOI: 10.3390/ijms21062132] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/19/2020] [Accepted: 03/19/2020] [Indexed: 12/27/2022] Open
Abstract
l-type amino acid transporter 1 (LAT1) is an amino acid transporter that is overexpressed in several types of cancer and, thus, it can be a potential target for chemotherapy. The objectives of this study were to (a) synthesize LAT1-targeted chlorambucil derivatives and (b) evaluate their LAT1-mediated cellular uptake as well as antiproliferative activity in vitro in the human breast cancer MCF-7 cell line. Chlorambucil was conjugated to l-tyrosine—an endogenous LAT1 substrate—via either ester or amide linkage (compounds 1 and 2, respectively). While chlorambucil itself did not bind to LAT1, its derivatives 1 and 2 bound to LAT1 with a similar affinity as with l-tyrosine and their respective cellular uptake was significantly higher than that of chlorambucil in MCF-7. The results of our cellular uptake study are indicative of antiproliferative activity, as a higher intracellular uptake of chlorambucil derivatives resulted in greater cytotoxicity than chlorambucil by itself. LAT1 thus contributes to intracellular uptake of chlorambucil derivatives and, therefore, increases antiproliferative activity. The understanding gained from our research can be used in the development of LAT1-targeted anticancer drugs and prodrugs for site-selective and enhanced chemotherapeutic activity.
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Affiliation(s)
- Piman Pocasap
- Division of Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand;
- Human High Performance and Health Promotion Research Institute, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Natthida Weerapreeyakul
- Division of Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand;
- Human High Performance and Health Promotion Research Institute, Khon Kaen University, Khon Kaen 40002, Thailand
- Correspondence: (N.W.); (J.R.)
| | - Juri Timonen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.T.); (J.J.); (J.L.); (J.K.)
| | - Juulia Järvinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.T.); (J.J.); (J.L.); (J.K.)
| | - Jukka Leppänen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.T.); (J.J.); (J.L.); (J.K.)
| | - Jussi Kärkkäinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.T.); (J.J.); (J.L.); (J.K.)
| | - Jarkko Rautio
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; (J.T.); (J.J.); (J.L.); (J.K.)
- Correspondence: (N.W.); (J.R.)
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Scalise M, Pochini L, Galluccio M, Console L, Indiveri C. Glutamine transporters as pharmacological targets: From function to drug design. Asian J Pharm Sci 2020; 15:207-219. [PMID: 32373200 PMCID: PMC7193454 DOI: 10.1016/j.ajps.2020.02.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 02/18/2020] [Accepted: 02/29/2020] [Indexed: 12/17/2022] Open
Abstract
Among the different targets of administered drugs, there are membrane transporters that play also a role in drug delivery and disposition. Moreover, drug-transporter interactions are responsible for off-target effects of drugs underlying their toxicity. The improvement of the drug design process is subjected to the identification of those membrane transporters mostly relevant for drug absorption, delivery and side effect production. A peculiar group of proteins with great relevance to pharmacology is constituted by the membrane transporters responsible for managing glutamine traffic in different body districts. The interest around glutamine metabolism lies in its physio-pathological role; glutamine is considered a conditionally essential amino acid because highly proliferative cells have an increased request of glutamine that cannot be satisfied only by endogenous synthesis. Then, glutamine transporters provide cells with this special nutrient. Among the glutamine transporters, SLC1A5, SLC6A14, SLC6A19, SLC7A5, SLC7A8 and some members of SLC38 family are the best characterized, so far, in both physiological and pathological conditions. Few 3D structures have been solved by CryoEM; other structural data on these transporters have been obtained by computational analysis. Interactions with drugs have been described for several transporters of this group. For some of them, the studies are at an advanced stage, for others, the studies are still in nuce and novel biochemical findings open intriguing perspectives.
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Affiliation(s)
- Mariafrancesca Scalise
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Lorena Pochini
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Michele Galluccio
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Lara Console
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Cesare Indiveri
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
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18
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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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19
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Rigorous sampling of docking poses unveils binding hypothesis for the halogenated ligands of L-type Amino acid Transporter 1 (LAT1). Sci Rep 2019; 9:15061. [PMID: 31636293 PMCID: PMC6803698 DOI: 10.1038/s41598-019-51455-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 09/24/2019] [Indexed: 12/15/2022] Open
Abstract
L-type Amino acid Transporter 1 (LAT1) plays a significant role in the growth and propagation of cancer cells by facilitating the cross-membrane transport of essential nutrients, and is an attractive drug target. Several halogen-containing L-phenylalanine-based ligands display high affinity and high selectivity for LAT1; nonetheless, their molecular mechanism of binding remains unclear. In this study, a combined in silico strategy consisting of homology modeling, molecular docking, and Quantum Mechanics-Molecular Mechanics (QM-MM) simulation was applied to elucidate the molecular basis of ligand binding in LAT1. First, a homology model of LAT1 based on the atomic structure of a prokaryotic homolog was constructed. Docking studies using a set of halogenated ligands allowed for deriving a binding hypothesis. Selected docking poses were subjected to QM-MM calculations to investigate the halogen interactions. Collectively, the results highlight the dual nature of the ligand-protein binding mode characterized by backbone hydrogen bond interactions of the amino acid moiety of the ligands and residues I63, S66, G67, F252, G255, as well as hydrophobic interactions of the ligand’s side chains with residues I139, I140, F252, G255, F402, W405. QM-MM optimizations indicated that the electrostatic interactions involving halogens contribute to the binding free energy. Importantly, our results are in good agreement with the recently unraveled cryo-Electron Microscopy structures of LAT1.
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20
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Hall C, Wolfe H, Wells A, Chien HC, Colas C, Schlessinger A, Giacomini KM, Thomas AA. l-Type amino acid transporter 1 activity of 1,2,3-triazolyl analogs of l-histidine and l-tryptophan. Bioorg Med Chem Lett 2019; 29:2254-2258. [PMID: 31248771 DOI: 10.1016/j.bmcl.2019.06.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 06/12/2019] [Accepted: 06/19/2019] [Indexed: 01/03/2023]
Abstract
A series of 1,2,3-triazole analogs of the amino acids l-histidine and l-tryptophan were modeled, synthesized and tested for l-type amino acid transporter 1 (LAT1; SLC7A5) activity to guide the design of amino acid-drug conjugates (prodrugs). These triazoles were conveniently prepared by the highly convergent Huisgen 1,3-dipolar cycloaddition (Click Chemistry). Despite comparable predicted binding modes, triazoles generally demonstrated reduced cell uptake and LAT1 binding potency relative to their natural amino acid counterparts. The structure-activity relationship (SAR) data for these triazoles has important ramifications for treating cancer and brain disorders using amino acid prodrugs or LAT1 inhibitors.
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Affiliation(s)
- Colton Hall
- Department of Chemistry, University of Nebraska at Kearney, Kearney, NE 69949, USA
| | - Hannah Wolfe
- Department of Chemistry, University of Nebraska at Kearney, Kearney, NE 69949, USA
| | - Alyssa Wells
- Department of Chemistry, University of Nebraska at Kearney, Kearney, NE 69949, USA
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Claire Colas
- Department of Pharmacological Sciences, Icahn School of Medicine at Mt. Sinai, New York, NY 10029, USA
| | - Avner Schlessinger
- Department of Pharmacological Sciences, Icahn School of Medicine at Mt. Sinai, New York, NY 10029, USA
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Allen A Thomas
- Department of Chemistry, University of Nebraska at Kearney, Kearney, NE 69949, USA.
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21
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Cryo-EM structure of the human L-type amino acid transporter 1 in complex with glycoprotein CD98hc. Nat Struct Mol Biol 2019; 26:510-517. [DOI: 10.1038/s41594-019-0237-7] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 04/26/2019] [Indexed: 02/07/2023]
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22
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Singh N, Scalise M, Galluccio M, Wieder M, Seidel T, Langer T, Indiveri C, Ecker GF. Discovery of Potent Inhibitors for the Large Neutral Amino Acid Transporter 1 (LAT1) by Structure-Based Methods. Int J Mol Sci 2018; 20:ijms20010027. [PMID: 30577601 PMCID: PMC6337383 DOI: 10.3390/ijms20010027] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/11/2018] [Accepted: 12/15/2018] [Indexed: 12/20/2022] Open
Abstract
The large neutral amino acid transporter 1 (LAT1) is a promising anticancer target that is required for the cellular uptake of essential amino acids that serve as building blocks for cancer growth and proliferation. Here, we report a structure-based approach to identify chemically diverse and potent inhibitors of LAT1. First, a homology model of LAT1 that is based on the atomic structures of the prokaryotic homologs was constructed. Molecular docking of nitrogen mustards (NMs) with a wide range of affinity allowed for deriving a common binding mode that could explain the structure−activity relationship pattern in NMs. Subsequently, validated binding hypotheses were subjected to molecular dynamics simulation, which allowed for extracting a set of dynamic pharmacophores. Finally, a library of ~1.1 million molecules was virtually screened against these pharmacophores, followed by docking. Biological testing of the 30 top-ranked hits revealed 13 actives, with the best compound showing an IC50 value in the sub-μM range.
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Affiliation(s)
- Natesh Singh
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
| | - Mariafrancesca Scalise
- Department DiBEST, Unit of Biochemistry & Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy.
| | - Michele Galluccio
- Department DiBEST, Unit of Biochemistry & Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy.
| | - Marcus Wieder
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
| | - Thomas Seidel
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
| | - Thierry Langer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
| | - Cesare Indiveri
- Department DiBEST, Unit of Biochemistry & Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, Italy.
| | - Gerhard F Ecker
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
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Chien HC, Colas C, Finke K, Springer S, Stoner L, Zur AA, Venteicher B, Campbell J, Hall C, Flint A, Augustyn E, Hernandez C, Heeren N, Hansen L, Anthony A, Bauer J, Fotiadis D, Schlessinger A, Giacomini KM, Thomas AA. Reevaluating the Substrate Specificity of the L-Type Amino Acid Transporter (LAT1). J Med Chem 2018; 61:7358-7373. [PMID: 30048132 DOI: 10.1021/acs.jmedchem.8b01007] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The L-type amino acid transporter 1 (LAT1, SLC7A5) transports essential amino acids across the blood-brain barrier (BBB) and into cancer cells. To utilize LAT1 for drug delivery, potent amino acid promoieties are desired, as prodrugs must compete with millimolar concentrations of endogenous amino acids. To better understand ligand-transporter interactions that could improve potency, we developed structural LAT1 models to guide the design of substituted analogues of phenylalanine and histidine. Furthermore, we evaluated the structure-activity relationship (SAR) for both enantiomers of naturally occurring LAT1 substrates. Analogues were tested in cis-inhibition and trans-stimulation cell assays to determine potency and uptake rate. Surprisingly, LAT1 can transport amino acid-like substrates with wide-ranging polarities including those containing ionizable substituents. Additionally, the rate of LAT1 transport was generally nonstereoselective even though enantiomers likely exhibit different binding modes. Our findings have broad implications to the development of new treatments for brain disorders and cancer.
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Affiliation(s)
- Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences , University of California, San Francisco , San Francisco , California 94158 , United States
| | - Claire Colas
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States
| | - Karissa Finke
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Seth Springer
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Laura Stoner
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Arik A Zur
- Department of Bioengineering and Therapeutic Sciences , University of California, San Francisco , San Francisco , California 94158 , United States
| | - Brooklynn Venteicher
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Jerome Campbell
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Colton Hall
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Andrew Flint
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Evan Augustyn
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Christopher Hernandez
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Nathan Heeren
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Logan Hansen
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Abby Anthony
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Justine Bauer
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
| | - Dimitrios Fotiadis
- Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure , University of Bern , 3012 Bern , Switzerland
| | - Avner Schlessinger
- Department of Pharmacological Sciences , Icahn School of Medicine at Mount Sinai , New York , New York 10029 , United States
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences , University of California, San Francisco , San Francisco , California 94158 , United States
| | - Allen A Thomas
- Department of Chemistry , University of Nebraska at Kearney , Kearney , Nebraska 68849 , United States
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Kärkkäinen J, Gynther M, Kokkola T, Petsalo A, Auriola S, Lahtela-Kakkonen M, Laine K, Rautio J, Huttunen KM. Structural properties for selective and efficient l-type amino acid transporter 1 (LAT1) mediated cellular uptake. Int J Pharm 2018; 544:91-99. [DOI: 10.1016/j.ijpharm.2018.04.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/13/2018] [Accepted: 04/13/2018] [Indexed: 12/24/2022]
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Singh N, Ecker GF. Insights into the Structure, Function, and Ligand Discovery of the Large Neutral Amino Acid Transporter 1, LAT1. Int J Mol Sci 2018; 19:E1278. [PMID: 29695141 PMCID: PMC5983779 DOI: 10.3390/ijms19051278] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 04/18/2018] [Accepted: 04/19/2018] [Indexed: 12/31/2022] Open
Abstract
The large neutral amino acid transporter 1 (LAT1, or SLC7A5) is a sodium- and pH-independent transporter, which supplies essential amino acids (e.g., leucine, phenylalanine) to cells. It plays an important role at the Blood⁻Brain Barrier (BBB) where it facilitates the transport of thyroid hormones, pharmaceuticals (e.g., l-DOPA, gabapentin), and metabolites into the brain. Moreover, its expression is highly upregulated in various types of human cancer that are characterized by an intense demand for amino acids for growth and proliferation. Therefore, LAT1 is believed to be an important drug target for cancer treatment. With the crystallization of the arginine/agmatine antiporter (AdiC) from Escherichia Coli, numerous homology models of LAT1 have been built to elucidate the substrate binding site, ligand⁻transporter interaction, and structure⁻function relationship. The use of these models in combination with molecular docking and experimental testing has identified novel chemotypes of ligands of LAT1. Here, we highlight the structure, function, transport mechanism, and homology modeling of LAT1. Additionally, results from structure⁻function studies performed on LAT1 are addressed, which have enhanced our knowledge of the mechanism of substrate binding and translocation. This is followed by a discussion on ligand- and structure-based approaches, with an emphasis on elucidating the molecular basis of LAT1 inhibition. Finally, we provide an exhaustive summary of different LAT1 inhibitors that have been identified so far, including the recently discovered irreversible covalent inhibitors.
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Affiliation(s)
- Natesh Singh
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
| | - Gerhard F Ecker
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.
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Puris E, Gynther M, Huttunen J, Petsalo A, Huttunen KM. L-type amino acid transporter 1 utilizing prodrugs: How to achieve effective brain delivery and low systemic exposure of drugs. J Control Release 2017; 261:93-104. [DOI: 10.1016/j.jconrel.2017.06.023] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 06/18/2017] [Accepted: 06/24/2017] [Indexed: 10/19/2022]
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Zur AA, Chien HC, Augustyn E, Flint A, Heeren N, Finke K, Hernandez C, Hansen L, Miller S, Lin L, Giacomini KM, Colas C, Schlessinger A, Thomas AA. LAT1 activity of carboxylic acid bioisosteres: Evaluation of hydroxamic acids as substrates. Bioorg Med Chem Lett 2016; 26:5000-5006. [PMID: 27624080 DOI: 10.1016/j.bmcl.2016.09.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/27/2016] [Accepted: 09/01/2016] [Indexed: 01/23/2023]
Abstract
Large neutral amino acid transporter 1 (LAT1) is a solute carrier protein located primarily in the blood-brain barrier (BBB) that offers the potential to deliver drugs to the brain. It is also up-regulated in cancer cells, as part of a tumor's increased metabolic demands. Previously, amino acid prodrugs have been shown to be transported by LAT1. Carboxylic acid bioisosteres may afford prodrugs with an altered physicochemical and pharmacokinetic profile than those derived from natural amino acids, allowing for higher brain or tumor levels of drug and/or lower toxicity. The effect of replacing phenylalanine's carboxylic acid with a tetrazole, acylsulfonamide and hydroxamic acid (HA) bioisostere was examined. Compounds were tested for their ability to be LAT1 substrates using both cis-inhibition and trans-stimulation cell assays. As HA-Phe demonstrated weak substrate activity, its structure-activity relationship (SAR) was further explored by synthesis and testing of HA derivatives of other LAT1 amino acid substrates (i.e., Tyr, Leu, Ile, and Met). The potential for a false positive in the trans-stimulation assay caused by parent amino acid was evaluated by conducting compound stability experiments for both HA-Leu and the corresponding methyl ester derivative. We concluded that HA's are transported by LAT1. In addition, our results lend support to a recent account that amino acid esters are LAT1 substrates, and that hydrogen bonding may be as important as charge for interaction with the transporter binding site.
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Affiliation(s)
- Arik A Zur
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158, United States.
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158, United States
| | - Evan Augustyn
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Andrew Flint
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Nathan Heeren
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Karissa Finke
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Christopher Hernandez
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Logan Hansen
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Sydney Miller
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States
| | - Lawrence Lin
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158, United States
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158, United States
| | - Claire Colas
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States
| | - Avner Schlessinger
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States
| | - Allen A Thomas
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE 68849, United States.
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Augustyn E, Finke K, Zur AA, Hansen L, Heeren N, Chien HC, Lin L, Giacomini KM, Colas C, Schlessinger A, Thomas AA. LAT-1 activity of meta-substituted phenylalanine and tyrosine analogs. Bioorg Med Chem Lett 2016; 26:2616-2621. [PMID: 27106710 DOI: 10.1016/j.bmcl.2016.04.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/08/2016] [Accepted: 04/09/2016] [Indexed: 12/23/2022]
Abstract
The transporter protein Large-neutral Amino Acid Transporter 1 (LAT-1, SLC7A5) is responsible for transporting amino acids such as tyrosine and phenylalanine as well as thyroid hormones, and it has been exploited as a drug delivery mechanism. Recently its role in cancer has become increasingly appreciated, as it has been found to be up-regulated in many different tumor types, and its expression levels have been correlated with prognosis. Substitution at the meta position of aromatic amino acids has been reported to increase affinity for LAT-1; however, the SAR for this position has not previously been explored. Guided by newly refined computational models of the binding site, we hypothesized that groups capable of filling a hydrophobic pocket would increase binding to LAT-1, resulting in improved substrates relative to parent amino acid. Tyrosine and phenylalanine analogs substituted at the meta position with halogens, alkyl and aryl groups were synthesized and tested in cis-inhibition and trans-stimulation cell assays to determine activity. Contrary to our initial hypothesis we found that lipophilicity was correlated with diminished substrate activity and increased inhibition of the transporter. The synthesis and SAR of meta-substituted phenylalanine and tyrosine analogs is described.
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Affiliation(s)
- Evan Augustyn
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE, 68849
| | - Karissa Finke
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE, 68849
| | - Arik A Zur
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158
| | - Logan Hansen
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE, 68849
| | - Nathan Heeren
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE, 68849
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158
| | - Lawrence Lin
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, Schools of Pharmacy and Medicine, University of California San Francisco, San Francisco, CA 94158
| | - Claire Colas
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Avner Schlessinger
- Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Allen A Thomas
- Department of Chemistry, University of Nebraska Kearney, Kearney, NE, 68849
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Development of a cell-based screening method for compounds that inhibit or are transported by large neutral amino acid transporter 1, a key transporter at the blood-brain barrier. Anal Biochem 2015; 486:81-5. [PMID: 26151684 DOI: 10.1016/j.ab.2015.06.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 06/20/2015] [Accepted: 06/30/2015] [Indexed: 11/24/2022]
Abstract
Large neutral amino acid transporter 1 (LAT1) transports neutral amino acids with aromatic or branched side chains as well as their derivatives or prodrugs. Because the transporter is highly expressed at the blood-brain barrier and in some tumor cells, it is a potential target to treat brain disease and cancer. Therefore, it is essential to develop a method to screen for LAT1 inhibitors or for therapeutic compounds that it can transport. In this study, one such method was developed that combines an in vitro cell-based assay with high-throughput ultra-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-QQQ-MS). Using this method, candidate compounds could be tested for the ability to inhibit or to compete with uptake of gabapentin, an LAT1 substrate, in HT-29 cells, which abundantly express the transporter. Gabapentin uptake is measured by mass spectrometry, which requires as little as 6min/sample and will enable analysis of large numbers of samples. We anticipate that the method will be useful to identify LAT1 inhibitors or substrates without the need for animals or radioactive labeling.
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Napolitano L, Scalise M, Galluccio M, Pochini L, Albanese LM, Indiveri C. LAT1 is the transport competent unit of the LAT1/CD98 heterodimeric amino acid transporter. Int J Biochem Cell Biol 2015; 67:25-33. [PMID: 26256001 DOI: 10.1016/j.biocel.2015.08.004] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 06/10/2015] [Accepted: 08/04/2015] [Indexed: 01/25/2023]
Abstract
LAT1 (SLC7A5) and CD98 (SLC3A2) constitute a heterodimeric transmembrane protein complex that catalyzes amino acid transport. Whether one or both subunits are competent for transport is still unclear. The present work aims to solve this question using different experimental strategies. Firstly, LAT1 and CD98 were immuno-detected in protein extracts from SiHa cells. Under oxidizing conditions, i.e., without addition of SH (thiol) reducing agent DTE, both proteins were revealed as a 120kDa major band. Upon DTE treatment separated bands, corresponding to LAT1(35kDa) or CD98(80kDa), were detected. LAT1 function was evaluated in intact cells as BCH sensitive [(3)H]His transport inhibited by hydrophobic amino acids. Antiport of [(3)H]His was measured in proteoliposomes reconstituted with SiHa cell extract in presence of internal His. Transport was increased by DTE. Hydrophobic amino acids were best inhibitors in addition to hydrophilic Tyr, Gln, Asn and Lys. Cys, Tyr and Gln, included in the intraliposomal space, were transported in antiport with external [(3)H]His. Similar experiments were performed in proteoliposomes reconstituted with the recombinant purified hLAT1. Results overlapping those obtained with native protein were achieved. Lower transport of [(3)H]Leu and [(3)H]Gln with respect to [(3)H]His was detected. Kinetic asymmetry was found with external Km for His lower than internal one. No transport was detected in proteoliposomes reconstituted with recombinant hCD98. The experimental data demonstrate that LAT1 is the sole transport competent subunit of the heterodimer. This conclusion has important outcome for following studies on functional characterization and identification of specific inhibitors with potential application in human therapy.
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Affiliation(s)
- Lara Napolitano
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Michele Galluccio
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Lorena Pochini
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Leticia Maria Albanese
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via Bucci 4C, 87036 Arcavacata di Rende, Italy
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via Bucci 4C, 87036 Arcavacata di Rende, Italy.
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Amino acid ester prodrugs conjugated to the α-carboxylic acid group do not display affinity for the L-type amino acid transporter 1 (LAT1). Eur J Pharm Sci 2015; 66:36-40. [DOI: 10.1016/j.ejps.2014.09.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 09/30/2014] [Accepted: 09/30/2014] [Indexed: 11/22/2022]
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32
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Kadiyala KG, Datta A, Tanwar J, Adhikari A, Kumar BSH, Chuttani K, Thirumal M, Mishra AK. Metal Based Imaging Probes of DO3A-Act-Met for LAT1 Mediated Methionine Specific Tumors : Synthesis and Preclinical Evaluation. Pharm Res 2014; 32:955-67. [DOI: 10.1007/s11095-014-1509-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 08/29/2014] [Indexed: 11/30/2022]
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Ylikangas H, Malmioja K, Peura L, Gynther M, Nwachukwu EO, Leppänen J, Laine K, Rautio J, Lahtela-Kakkonen M, Huttunen KM, Poso A. Quantitative Insight into the Design of Compounds Recognized by theL-Type Amino Acid Transporter 1 (LAT1). ChemMedChem 2014; 9:2699-707. [DOI: 10.1002/cmdc.201402281] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Indexed: 11/07/2022]
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Tachikawa M, Uchida Y, Ohtsuki S, Terasaki T. Recent Progress in Blood–Brain Barrier and Blood–CSF Barrier Transport Research: Pharmaceutical Relevance for Drug Delivery to the Brain. DRUG DELIVERY TO THE BRAIN 2014. [DOI: 10.1007/978-1-4614-9105-7_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Abbott NJ. Blood-brain barrier structure and function and the challenges for CNS drug delivery. J Inherit Metab Dis 2013; 36:437-49. [PMID: 23609350 DOI: 10.1007/s10545-013-9608-0] [Citation(s) in RCA: 543] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 04/02/2013] [Accepted: 04/03/2013] [Indexed: 12/12/2022]
Abstract
The neurons of the central nervous system (CNS) require precise control of their bathing microenvironment for optimal function, and an important element in this control is the blood-brain barrier (BBB). The BBB is formed by the endothelial cells lining the brain microvessels, under the inductive influence of neighbouring cell types within the 'neurovascular unit' (NVU) including astrocytes and pericytes. The endothelium forms the major interface between the blood and the CNS, and by a combination of low passive permeability and presence of specific transport systems, enzymes and receptors regulates molecular and cellular traffic across the barrier layer. A number of methods and models are available for examining BBB permeation in vivo and in vitro, and can give valuable information on the mechanisms by which therapeutic agents and constructs permeate, ways to optimize permeation, and implications for drug discovery, delivery and toxicity. For treating lysosomal storage diseases (LSDs), models can be included that mimic aspects of the disease, including genetically-modified animals, and in vitro models can be used to examine the effects of cells of the NVU on the BBB under pathological conditions. For testing CNS drug delivery, several in vitro models now provide reliable prediction of penetration of drugs including large molecules and artificial constructs with promising potential in treating LSDs. For many of these diseases it is still not clear how best to deliver appropriate drugs to the CNS, and a concerted approach using a variety of models and methods can give critical insights and indicate practical solutions.
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Affiliation(s)
- N Joan Abbott
- BBB Group, Institute of Pharmaceutical Science, King's College London, London, UK.
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