1
|
Bele T, Turk T, Križaj I. Nicotinic acetylcholine receptors in cancer: Limitations and prospects. Biochim Biophys Acta Mol Basis Dis 2024; 1870:166875. [PMID: 37673358 DOI: 10.1016/j.bbadis.2023.166875] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 08/09/2023] [Accepted: 08/31/2023] [Indexed: 09/08/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) have long been considered to solely mediate neurotransmission. However, their widespread distribution in the human body suggests a more diverse physiological role. Additionally, the expression of nAChRs is increased in certain cancers, such as lung cancer, and has been associated with cell proliferation, epithelial-to-mesenchymal cell transition, angiogenesis and apoptosis prevention. Several compounds that interact with these receptors have been identified as potential therapeutic agents. They have been tested as drugs for treating nicotine addiction, alcoholism, depression, pain and Alzheimer's disease. This review focuses on nAChR-mediated signalling in cancer, presenting opportunities for the development of innovative nAChR-based anticancer drugs. It displays the differences in expression of each nAChR subunit between normal and cancer cells for selected cancer types, highlighting their possible involvement in specific cases. Antagonists of nAChRs that could complement existing cancer therapies are summarised and critically discussed. We hope that this review will stimulate further research on the role of nAChRs in cancer potentially leading to innovative cancer therapies.
Collapse
Affiliation(s)
- T Bele
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Vrazov trg 2, SI-1000 Ljubljana, Slovenia.
| | - T Turk
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia.
| | - I Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
| |
Collapse
|
2
|
Ho TNT, Abraham N, Lewis RJ. Unravelling the allosteric binding mode of αD-VxXXB at nicotinic acetylcholine receptors. Front Pharmacol 2023; 14:1170514. [PMID: 37124228 PMCID: PMC10133702 DOI: 10.3389/fphar.2023.1170514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/30/2023] [Indexed: 05/02/2023] Open
Abstract
αD-conotoxins are 11 kDa homodimers that potently inhibit nicotinic acetylcholine receptors (nAChRs) through a non-competitive (allosteric) mechanism. In this study, we describe the allosteric binding mode of the granulin-like C-terminal (CTD) of VxXXB bound to Lymnea stagnalis acetylcholine binding protein (Ls-AChBP), a soluble homologue of the extracellular ligand-binding domain of nAChRs. This co-crystal complex revealed a novel allosteric binding site for nAChR antagonists outside the C-loop that caps the orthosteric site defined by the nAChR agonist nicotine and the antagonist epibatidine. Mutational and docking studies on Ls-AChBP supported a two-site binding mode for full-length VxXXB, with the first CTD binding site located outside the C-loop as seen in the co-crystal complex, with a second CTD binding site located near the N-terminal end of the adjacent subunit of AChBP. These results provide new structural insight into a novel allosteric mechanism of nAChR inhibition and define the cooperative binding mode of the N-terminal domain linked granulin core domains of αD-conotoxins.
Collapse
|
3
|
Ho TNT, Abraham N, Lewis RJ. Synthesis of full-length homodimer αD-VxXXB that targets human α7 nicotinic acetylcholine receptors. RSC Med Chem 2022; 13:1410-1419. [PMID: 36439982 PMCID: PMC9667780 DOI: 10.1039/d2md00188h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/05/2022] [Indexed: 09/07/2023] Open
Abstract
αD-Conotoxin VxXXB is a pseudo-homodimer that allosterically inhibits nicotinic acetylcholine receptors (nAChRs) with high potency and selectivity. However, challenges in synthesizing αD-conotoxins have hindered further structure-function studies on this novel class of peptides. To address this gap, we synthesized and characterized its C-terminal domain (CTD) and N-terminal domain (NTD). The CTD inhibited α7 nAChRs (IC50 of 23 nM, measured via FLIPR assays) and bound at the acetylcholine binding protein (Ls-AChBP) through an allosteric binding mode determined from radioligand binding assays. The anti-parallel dimeric NTD synthesised via a regioselective strategy also inhibited α7 nAChRs but with reduced potency (IC50 of 30 μM). The α-ketoacid-hydroxylamine (KAHA) method generated CTD linked to the NTD (VxXXB-NC; α7 IC50 of 27 nM) and full-length synthetic VxXXB variant (α7 IC50 of 11 nM), while the three other native chemical ligation approaches proved unsuccessful. This work underpins further characterisation of the structural components contributing to αD-conotoxin affinity, selectivity and allosteric inhibition of nAChR function that may prove useful in the development of new treatments for nAChR-related disorders.
Collapse
Affiliation(s)
- Thao N T Ho
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland St Lucia Queensland 4067 Australia
| | - Nikita Abraham
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland St Lucia Queensland 4067 Australia
| | - Richard J Lewis
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland St Lucia Queensland 4067 Australia
| |
Collapse
|
4
|
A Novel Dimeric Conotoxin, FrXXA, from the Vermivorous Cone Snail Conus fergusoni, of the Eastern Pacific, Inhibits Nicotinic Acetylcholine Receptors. Toxins (Basel) 2022; 14:toxins14080510. [PMID: 35893752 PMCID: PMC9330476 DOI: 10.3390/toxins14080510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/05/2022] [Accepted: 07/10/2022] [Indexed: 02/04/2023] Open
Abstract
We isolated a new dimeric conotoxin with inhibitory activity against neuronal nicotinic acetylcholine receptors. Edman degradation and transcriptomic studies indicate a homodimeric conotoxin composed by two chains of 47 amino acid in length. It has the cysteine framework XX and 10 disulfide bonds. According to conotoxin nomenclature, it has been named as αD-FrXXA. The αD-FrXXA conotoxin inhibited the ACh-induced response on nAChR with a IC50 of 125 nM on hα7, 282 nM on hα3β2, 607 nM on α4β2, 351 nM on mouse adult muscle, and 447 nM on mouse fetal muscle. This is first toxin characterized from C. fergusoni and, at the same time, the second αD-conotoxin characterized from a species of the Eastern Pacific.
Collapse
|
5
|
Jin AH, Muttenthaler M, Dutertre S, Himaya SWA, Kaas Q, Craik DJ, Lewis RJ, Alewood PF. Conotoxins: Chemistry and Biology. Chem Rev 2019; 119:11510-11549. [PMID: 31633928 DOI: 10.1021/acs.chemrev.9b00207] [Citation(s) in RCA: 161] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The venom of the marine predatory cone snails (genus Conus) has evolved for prey capture and defense, providing the basis for survival and rapid diversification of the now estimated 750+ species. A typical Conus venom contains hundreds to thousands of bioactive peptides known as conotoxins. These mostly disulfide-rich and well-structured peptides act on a wide range of targets such as ion channels, G protein-coupled receptors, transporters, and enzymes. Conotoxins are of interest to neuroscientists as well as drug developers due to their exquisite potency and selectivity, not just against prey but also mammalian targets, thereby providing a rich source of molecular probes and therapeutic leads. The rise of integrated venomics has accelerated conotoxin discovery with now well over 10,000 conotoxin sequences published. However, their structural and pharmacological characterization lags considerably behind. In this review, we highlight the diversity of new conotoxins uncovered since 2014, their three-dimensional structures and folds, novel chemical approaches to their syntheses, and their value as pharmacological tools to unravel complex biology. Additionally, we discuss challenges and future directions for the field.
Collapse
Affiliation(s)
- Ai-Hua Jin
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Markus Muttenthaler
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia.,Institute of Biological Chemistry, Faculty of Chemistry , University of Vienna , 1090 Vienna , Austria
| | - Sebastien Dutertre
- Département des Acides Amines, Peptides et Protéines, Unité Mixte de Recherche 5247, Université Montpellier 2-Centre Nationale de la Recherche Scientifique , Institut des Biomolécules Max Mousseron , Place Eugène Bataillon , 34095 Montpellier Cedex 5 , France
| | - S W A Himaya
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Quentin Kaas
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - David J Craik
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Richard J Lewis
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| | - Paul F Alewood
- Institute for Molecular Bioscience , The University of Queensland , Brisbane Queensland 4072 , Australia
| |
Collapse
|
6
|
Abstract
Covering: January to December 2017This review covers the literature published in 2017 for marine natural products (MNPs), with 740 citations (723 for the period January to December 2017) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1490 in 477 papers for 2017), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that led to the revision of structures or stereochemistries, have been included. Geographic distributions of MNPs at a phylogenetic level are reported.
Collapse
Affiliation(s)
- Anthony R Carroll
- School of Environment and Science, Griffith University, Gold Coast, Australia. and Griffith Institute for Drug Discovery, Griffith University, Brisbane, Australia
| | - Brent R Copp
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Rohan A Davis
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Australia
| | - Robert A Keyzers
- Centre for Biodiscovery, School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
| | | |
Collapse
|
7
|
Abraham N, Lewis RJ. Neuronal Nicotinic Acetylcholine Receptor Modulators from Cone Snails. Mar Drugs 2018; 16:E208. [PMID: 29899286 PMCID: PMC6024932 DOI: 10.3390/md16060208] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/25/2018] [Accepted: 06/06/2018] [Indexed: 12/15/2022] Open
Abstract
Marine cone snails are a large family of gastropods that have evolved highly potent venoms for predation and defense. The cone snail venom has exceptional molecular diversity in neuropharmacologically active compounds, targeting a range of receptors, ion channels, and transporters. These conotoxins have helped to dissect the structure and function of many of these therapeutically significant targets in the central and peripheral nervous systems, as well as unravelling the complex cellular mechanisms modulated by these receptors and ion channels. This review provides an overview of α-conotoxins targeting neuronal nicotinic acetylcholine receptors. The structure and activity of both classical and non-classical α-conotoxins are discussed, along with their contributions towards understanding nicotinic acetylcholine receptor (nAChR) structure and function.
Collapse
Affiliation(s)
- Nikita Abraham
- IMB Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia.
| | - Richard J Lewis
- IMB Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia.
| |
Collapse
|
8
|
α-Conotoxins to explore the molecular, physiological and pathophysiological functions of neuronal nicotinic acetylcholine receptors. Neurosci Lett 2017; 679:24-34. [PMID: 29199094 DOI: 10.1016/j.neulet.2017.11.063] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 12/22/2022]
Abstract
The vast diversity of neuronal nicotinic acetylcholine subunits expressed in the central and peripheral nervous systems, as well as in non-neuronal tissues, constitutes a formidable challenge for researchers and clinicians to decipher the role of particular subtypes, including complex subunit associations, in physiological and pathophysiological functions. Many natural products target the nAChRs, but there is no richer source of nicotinic ligands than the venom of predatory gastropods known as cone snails. Indeed, every single species of cone snail was shown to produce at least one type of such α-conotoxins. These tiny peptides (10-25 amino acids), constrained by disulfide bridges, proved to be unvaluable tools to investigate the structure and function of nAChRs, some of them having also therapeutic potential. In this review, we provide a recent update on the pharmacology and subtype specificity of several major α-conotoxins.
Collapse
|