1
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Watts SW, Townsend RR, Neubig RR. How New Developments in Pharmacology Receptor Theory Are Changing (Our Understanding of) Hypertension Therapy. Am J Hypertens 2024; 37:248-260. [PMID: 38150382 PMCID: PMC10941088 DOI: 10.1093/ajh/hpad121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 12/21/2023] [Indexed: 12/29/2023] Open
Abstract
BACKGROUND Many hypertension therapeutics were developed prior to major advances in drug receptor theory. Moreover, newer drugs may take advantage of some of the newly understood modalities of receptor function. GOAL The goal of this review is to provide an up-to-date summary of drug receptor theory. This is followed by a discussion of the drug classes recognized for treating hypertension to which new concepts in receptor theory apply. RESULTS We raise ideas for mechanisms of potential new antihypertensive drugs and whether they may take advantage of new theories in drug-receptor interaction.
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Affiliation(s)
- Stephanie W Watts
- Department of Pharmacology and Toxicology, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan 48824-131, USA
| | - Raymond R Townsend
- Department of Nephrology and Hypertension, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan 48824-131, USA
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2
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Foda BM, Neubig RR. Role of Rho/MRTF in Aggressive Vemurafenib-Resistant Murine Melanomas and Immune Checkpoint Upregulation. Int J Mol Sci 2023; 24:13785. [PMID: 37762086 PMCID: PMC10531039 DOI: 10.3390/ijms241813785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/01/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
Cutaneous melanoma is the deadliest skin cancer. Most have Ras-MAPK pathway (BRAFV600E or NRAS) mutations and highly effective targeted therapies exist; however, they and immune therapies are limited by resistance, in part driven by small GTPase (Rho and Rac) activation. To facilitate preclinical studies of combination therapies to provide durable responses, we describe the first mouse melanoma lines resistant to BRAF inhibitors. Treatment of mouse lines, YUMM1.7 and YUMMER, with vemurafenib (Vem), the BRAFV600E-selective inhibitor, resulted in high-level resistance (IC50 shifts 20-30-fold). Resistant cells showed enhanced activation of Rho and the downstream transcriptional coactivator, myocardin-related transcription factor (MRTF). Resistant cells exhibited increased stress fibers, nuclear translocation of MRTF-A, and an increased MRTF-A gene signature. Pharmacological inhibition of the Rho/MRTF pathway using CCG-257081 reduced viability of resistant lines and enhanced sensitivity to Vem. Remarkably, co-treatment of parental lines with Vem and CCG-257081 eliminated resistant colony development. Resistant cells grew more slowly in vitro, but they developed highly aggressive tumors with a shortened survival of tumor-bearing mice. Increased expression of immune checkpoint inhibitor proteins (ICIs) in resistant lines may contribute to aggressive in vivo behavior. Here, we introduce the first drug-resistant mouse melanoma models for assessing combinations of targeted and immune therapies.
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Affiliation(s)
- Bardees M. Foda
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48823, USA;
- Molecular Genetics and Enzymology Department, National Research Centre, Dokki 12622, Egypt
| | - Richard R. Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48823, USA;
- Nicholas V. Perricone, M.D. Division of Dermatology, Department of Medicine, Michigan State University, East Lansing, MI 48823, USA
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3
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Abdelgied M, Uhl K, Chen OG, Schultz C, Tripp K, Peraino AM, Paithankar S, Chen B, Tamae Kakazu M, Castillo Bahena A, Jager TE, Lawson C, Chesla DW, Pestov N, Modyanov NN, Prokop J, Neubig RR, Uhal BD, Girgis RE, Li X. Targeting ATP12A, a Nongastric Proton Pump α Subunit, for Idiopathic Pulmonary Fibrosis Treatment. Am J Respir Cell Mol Biol 2023; 68:638-650. [PMID: 36780662 PMCID: PMC10257074 DOI: 10.1165/rcmb.2022-0264oc] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 02/13/2023] [Indexed: 02/15/2023] Open
Abstract
Idiopathic pulmonary fibrosis (IPF) is a pathological condition of unknown etiology that results from injury to the lung and an ensuing fibrotic response that leads to the thickening of the alveolar walls and obliteration of the alveolar space. The pathogenesis is not clear, and there are currently no effective therapies for IPF. Small airway disease and mucus accumulation are prominent features in IPF lungs, similar to cystic fibrosis lung disease. The ATP12A gene encodes the α-subunit of the nongastric H+, K+-ATPase, which functions to acidify the airway surface fluid and impairs mucociliary transport function in patients with cystic fibrosis. It is hypothesized that the ATP12A protein may play a role in the pathogenesis of IPF. The authors' studies demonstrate that ATP12A protein is overexpressed in distal small airways from the lungs of patients with IPF compared with normal human lungs. In addition, overexpression of the ATP12A protein in mouse lungs worsened bleomycin induced experimental pulmonary fibrosis. This was prevented by a potassium competitive proton pump blocker, vonoprazan. These data support the concept that the ATP12A protein plays an important role in the pathogenesis of lung fibrosis. Inhibition of the ATP12A protein has potential as a novel therapeutic strategy in IPF treatment.
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Affiliation(s)
| | - Katie Uhl
- Department of Pediatrics and Human Development and
| | | | - Chad Schultz
- Department of Pediatrics and Human Development and
| | - Kaylie Tripp
- Department of Pediatrics and Human Development and
| | | | | | - Bin Chen
- Department of Pediatrics and Human Development and
- Department of Pharmacology and Toxicology and
| | - Maximiliano Tamae Kakazu
- Department of Medicine, College of Human Medicine, Michigan State University, Grand Rapids, Michigan
- Division of Pulmonary and Critical Care Medicine
| | | | - Tara E. Jager
- Richard Devos Heart and Lung Transplant Program, Spectrum Health, Grand Rapids, Michigan
| | - Cameron Lawson
- Richard Devos Heart and Lung Transplant Program, Spectrum Health, Grand Rapids, Michigan
| | | | - Nikolay Pestov
- Department of Physiology and Pharmacology and Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Health Science Campus, Toledo, Ohio
| | - Nikolai N. Modyanov
- Department of Physiology and Pharmacology and Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Health Science Campus, Toledo, Ohio
| | - Jeremy Prokop
- Department of Pediatrics and Human Development and
- Department of Pharmacology and Toxicology and
| | | | - Bruce D. Uhal
- Department of Physiology, Michigan State University, East Lansing, Michigan; and
| | - Reda E. Girgis
- Department of Medicine, College of Human Medicine, Michigan State University, Grand Rapids, Michigan
- Division of Pulmonary and Critical Care Medicine
- Richard Devos Heart and Lung Transplant Program, Spectrum Health, Grand Rapids, Michigan
| | - Xiaopeng Li
- Department of Pediatrics and Human Development and
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4
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Staerz S, Lisabeth EM, Njomen E, Dexheimer TS, Neubig RR, Tepe JJ. Development of a Cell-Based AlphaLISA Assay for High-Throughput Screening for Small Molecule Proteasome Modulators. ACS Omega 2023; 8:15650-15659. [PMID: 37151549 PMCID: PMC10157846 DOI: 10.1021/acsomega.3c01158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/12/2023] [Indexed: 05/09/2023]
Abstract
The balance between protein degradation and protein synthesis is a highly choreographed process generally called proteostasis. Most intracellular protein degradation occurs through the ubiquitin-proteasome system (UPS). This degradation takes place through either a ubiquitin-dependent or a ubiquitin-independent proteasomal pathway. The ubiquitin-independent pathway selectively targets unfolded proteins, including intrinsically disordered proteins (IDPs). Dysregulation of proteolysis can lead to the accumulation of IDPs, seen in the pathogenesis of various diseases, including cancer and neurodegeneration. Therefore, the enhancement of the proteolytic activity of the 20S proteasome using small molecules has been identified as a promising pathway to combat IDP accumulation. Currently, there are a limited number of known small molecules that enhance the activity of the 20S proteasome, and few are observed to exhibit enhanced proteasome activity in cell culture. Herein, we describe the development of a high-throughput screening assay to identify cell-permeable proteasome enhancers by utilizing an AlphaLISA platform that measures the degradation of a GFP conjugated intrinsically disordered protein, ornithine decarboxylase (ODC). Through the screening of the Prestwick and NIH Clinical Libraries, a kinase inhibitor, erlotinib, was identified as a new 20S proteasome enhancer, which enhances the degradation of ODC in cells and α-synuclein in vitro.
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Affiliation(s)
- Sophia
D. Staerz
- Department
of Chemistry, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Erika M. Lisabeth
- Department
of Chemistry, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Evert Njomen
- Department
of Chemistry, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Thomas S. Dexheimer
- Department
of Chemistry, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Richard R. Neubig
- Department
of Chemistry, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Jetze J. Tepe
- Department
of Chemistry, Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, United States
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5
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Pisanò CA, Mercatelli D, Mazzocchi M, Brugnoli A, Morella I, Fasano S, Zaveri NT, Brambilla R, O'Keeffe GW, Neubig RR, Morari M. Regulator of G-Protein Signalling 4 (RGS4) negatively modulates nociceptin/orphanin FQ opioid receptor signalling: Implication for l-Dopa-induced dyskinesia. Br J Pharmacol 2023; 180:927-942. [PMID: 34767639 DOI: 10.1111/bph.15730] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 10/11/2021] [Accepted: 10/18/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Regulator of G-protein signalling 4 (RGS4) is a signal transduction protein that accelerates intrinsic GTPase activity of Gαi/o and Gαq subunits, suppressing GPCR signalling. Here, we investigate whether RGS4 modulates nociceptin/orphanin FQ (N/OFQ) opioid (NOP) receptor signalling and if this modulation has relevance for l-Dopa-induced dyskinesia. EXPERIMENTAL APPROACH HEK293T cells transfected with NOP, NOP/RGS4 or NOP/RGS19 were challenged with N/OFQ and the small-molecule NOP agonist AT-403, using D1-stimulated cAMP levels as a readout. Primary rat striatal neurons and adult mouse striatal slices were challenged with either N/OFQ or AT-403 in the presence of the experimental RGS4 chemical probe, CCG-203920, and D1-stimulated cAMP or phosphorylated extracellular signal regulated kinase 1/2 (pERK) responses were monitored. In vivo, CCG-203920 was co-administered with AT-403 and l-Dopa to 6-hydroxydopamine hemilesioned rats, and dyskinetic movements, striatal biochemical correlates of dyskinesia (pERK and pGluR1 levels) and striatal RGS4 levels were measured. KEY RESULTS RGS4 expression reduced NOFQ and AT-403 potency and efficacy in HEK293T cells. CCG-203920 increased N/OFQ potency in primary rat striatal neurons and potentiated AT-403 response in mouse striatal slices. CCG-203920 enhanced AT-403-mediated inhibition of dyskinesia and its biochemical correlates, without compromising its motor-improving effects. Unilateral dopamine depletion caused bilateral reduction of RGS4 levels, which was reversed by l-Dopa. l-Dopa acutely up-regulated RGS4 in the lesioned striatum. CONCLUSIONS AND IMPLICATIONS RGS4 physiologically inhibits NOP receptor signalling. CCG-203920 enhanced NOP responses and improved the antidyskinetic potential of NOP receptor agonists, mitigating the effects of striatal RGS4 up-regulation occurring during dyskinesia expression. LINKED ARTICLES This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.
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Affiliation(s)
- Clarissa A Pisanò
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
| | - Daniela Mercatelli
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
| | - Martina Mazzocchi
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Alberto Brugnoli
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
| | - Ilaria Morella
- Neuroscience and Mental Health Research Institute, Division of Neuroscience, School of Biosciences, Cardiff University, Cardiff, UK
| | - Stefania Fasano
- Neuroscience and Mental Health Research Institute, Division of Neuroscience, School of Biosciences, Cardiff University, Cardiff, UK
| | - Nurulain T Zaveri
- Astraea Therapeutics, Medicinal Chemistry Division, Mountain View, California, USA
| | - Riccardo Brambilla
- Neuroscience and Mental Health Research Institute, Division of Neuroscience, School of Biosciences, Cardiff University, Cardiff, UK
- Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Gerard W O'Keeffe
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Michele Morari
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
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6
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Pawelec KM, Varnum M, Harkema JR, Auerbach B, Larsen SD, Neubig RR. Prevention of bleomycin-induced lung fibrosis via inhibition of the MRTF/SRF transcription pathway. Pharmacol Res Perspect 2022; 10:e01028. [PMID: 36426895 PMCID: PMC9695093 DOI: 10.1002/prp2.1028] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/21/2022] [Accepted: 10/11/2022] [Indexed: 11/26/2022] Open
Abstract
Bleomycin-induced lung fibrosis is a debilitating disease, linked to high morbidity and mortality in chemotherapy patients. The MRTF/SRF transcription pathway has been proposed as a potential therapeutic target, as it is critical for myofibroblast differentiation, a hallmark of fibrosis. In human lung fibroblasts, the MRTF/SRF pathway inhibitor, CCG-257081, effectively decreased mRNA levels of downstream genes: smooth muscle actin and connective tissue growth factor, with IC50 s of 4 and 15 μM, respectively. The ability of CCG-257081 to prevent inflammation and fibrosis, measured via pulmonary collagen content and histopathology, was tested in a murine model of bleomycin-induced lung fibrosis. Animals were given intraperitoneal bleomycin for 4 weeks and concurrently dosed with CCG-257081 (0, 10, 30, and 100 mg/kg PO), a clinical anti-fibrotic (nintedanib) or the clinical standard of care (prednisolone). Mice treated with 100 mg/kg CCG-257081 gained weight vs. vehicle-treated control mice, while those receiving nintedanib and prednisolone lost significant weight. Hydroxyproline content and histological findings in tissue of animals on 100 mg/kg CCG-257081 were not significantly different from naive tissue, indicating successful prevention. Measures of tissue fibrosis were comparable between CCG-257081 and nintedanib, but only the MRTF/SRF inhibitor decreased plasminogen activator inhibitor-1 (PAI-1), a marker linked to fibrosis, in bronchoalveolar lavage fluid. In contrast, prednisolone led to marked increases in lung fibrosis by all metrics. This study demonstrates the potential use of MRTF/SRF inhibitors to prevent bleomycin-induced lung fibrosis in a clinically relevant model of the disease.
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Affiliation(s)
| | - Megan Varnum
- FibrosIXEast LansingMichiganUSA,BBC Entrepreneurial Training and ConsultingChelseaMichiganUSA
| | - Jack R. Harkema
- Department of Pathology and Diagnostic InvestigationMichigan State UniversityEast LansingMichiganUSA,Department of Pharmacology & ToxicologyMichigan State UniversityEast LansingMichiganUSA
| | - Bruce Auerbach
- Office of Technology TransferUniversity of MichiganAnn ArborMichiganUSA
| | - Scott D. Larsen
- FibrosIXEast LansingMichiganUSA,Department of Medicinal ChemistryUniversity of MichiganAnn ArborMichiganUSA
| | - Richard R. Neubig
- FibrosIXEast LansingMichiganUSA,Department of Pharmacology & ToxicologyMichigan State UniversityEast LansingMichiganUSA
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7
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Feng H, Yuan Y, Williams MR, Roy AJ, Leipprandt J, Neubig RR. Mice With Monoallelic
GNAO1
Loss Exhibit Reduced Inhibitory Synaptic Input to Cerebellar Purkinje Cells. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r2992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Huijie Feng
- Pharmacology & ToxicologyMichigan State UniversityEast LansingMI
- NeurologyMichigan State UniversityEast LansingMI
| | - Yukun Yuan
- Pharmacology & ToxicologyMichigan State UniversityEast LansingMI
- Michigan State UniversityEast LansingMI
| | | | - Alex J. Roy
- Pharmacology & ToxicologyMichigan State UniversityEast LansingMI
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8
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Neubig RR. A Glowing Opportunity to Target YAP in Lung Fibrosis. Am J Respir Cell Mol Biol 2022; 67:1-2. [PMID: 35503038 PMCID: PMC9273223 DOI: 10.1165/rcmb.2022-0082ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Richard R Neubig
- Michigan State University, 3078, Pharmacology and Toxicology, East Lansing, Michigan, United States.,Michigan State University, 3078, Department of Medicine, Nicolas V. Perricone MD Division of Dermatology, East Lansing, Michigan, United States;
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9
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Misek SA, Foda BM, Dexheimer TS, Akram M, Conrad SE, Schmidt JC, Neubig RR, Gallo KA. BRAF Inhibitor Resistance Confers Increased Sensitivity to Mitotic Inhibitors. Front Oncol 2022; 12:766794. [PMID: 35444937 PMCID: PMC9015667 DOI: 10.3389/fonc.2022.766794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
Single agent and combination therapy with BRAFV600E/K and MEK inhibitors have remarkable efficacy against melanoma tumors with activating BRAF mutations, but in most cases BRAF inhibitor (BRAFi) resistance eventually develops. One resistance mechanism is reactivation of the ERK pathway. However, only about half of BRAFi resistance is due to ERK reactivation. The purpose of this study is to uncover pharmacological vulnerabilities of BRAFi-resistant melanoma cells, with the goal of identifying new therapeutic options for patients whose tumors have developed resistance to BRAFi/MEKi therapy. We screened a well-annotated compound library against a panel of isogenic pairs of parental and BRAFi-resistant melanoma cell lines to identify classes of compounds that selectively target BRAFi-resistant cells over their BRAFi-sensitive counterparts. Two distinct patterns of increased sensitivity to classes of pharmacological inhibitors emerged. In two cell line pairs, BRAFi resistance conferred increased sensitivity to compounds that share the property of cell cycle arrest at M-phase, including inhibitors of aurora kinase (AURK), polo-like kinase (PLK), tubulin, and kinesin. Live cell microscopy, used to track mitosis in real time, revealed that parental but not BRAFi-resistant melanoma cells were able to exit from compound-induced mitotic arrest through mitotic slippage, thus escaping death. Consistent with the key role of Cyclin B1 levels in regulating mitosis at the spindle checkpoint in arrested cells, we found lower Cyclin B1 levels in parental compared with BRAFi-resistant melanoma cells, suggesting that inability to down-regulate Cyclin B1 expression levels may explain the increased vulnerability of resistant cells to mitotic inhibitors. Another BRAFi-resistant cell line showed increased sensitivity to Chk1/2 inhibitors, which was associated with an accumulation of DNA damage, resulting in mitotic failure. This study demonstrates that BRAFi-resistance, in at least a subset of melanoma cells, confers vulnerability to pharmacological disruption of mitosis and suggests a targeted synthetic lethal approach for overcoming resistance to BRAF/MEK-directed therapies.
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Affiliation(s)
- Sean A Misek
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Bardees M Foda
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States.,Molecular Genetics and Enzymology Department, National Research Centre, Dokki, Egypt
| | - Thomas S Dexheimer
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Maisah Akram
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Susan E Conrad
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
| | - Jens C Schmidt
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI, United States.,Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI, United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States.,"Nicholas V. Perricone, M.D.", Division of Dermatology, Department of Medicine, Michigan State University, East Lansing, MI, United States
| | - Kathleen A Gallo
- Department of Physiology, Michigan State University, East Lansing, MI, United States
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10
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Feng H, Yuan Y, Williams MR, Roy AJ, Leipprandt JR, Neubig RR. MICE WITH GNAO1-ASSOCIATED MOVEMENT DISORDER EXHIBIT REDUCED INHIBITORY SYNAPTIC INPUT TO CEREBELLAR PURKINJE CELLS. J Neurophysiol 2022; 127:607-622. [PMID: 35080448 DOI: 10.1152/jn.00720.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
GNAO1 encodes Gαo, a heterotrimeric G protein alpha subunit in the Gi/o family. In this report, we used a Gnao1 mouse model "G203R" previously described as a "gain-of-function" Gnao1 mutant with movement abnormalities and enhanced seizure susceptibility. Here, we report an unexpected second mutation resulting in a loss-of-function Gαo protein and describe alterations in central synaptic transmission. Whole cell patch clamp recordings from Purkinje cells (PCs) in acute cerebellar slices from Gnao1 mutant mice showed significantly lower frequencies of spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs) compared to WT mice. There was no significant change in sEPSCs or mEPSCs. Whereas mIPSC frequency was reduced, mIPSC amplitudes were not affected, suggesting a presynaptic mechanism of action. A modest decrease in the number of molecular layer interneurons was insufficient to explain the magnitude of IPSC suppression. Paradoxically, Gi/o inhibitors (pertussis toxin), enhanced the mutant-suppressed mIPSC frequency and eliminated the difference between WT and Gnao1 mice. While GABAB receptor regulates mIPSCs, neither agonists nor antagonists of this receptor altered function in the mutant mouse PCs. This study is the first electrophysiological investigation of the role of Gi/o proteinin cerebellar synaptic transmission using an animal model with a loss-of-function Gi/o protein.
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Affiliation(s)
- Huijie Feng
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Yukun Yuan
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Michael R Williams
- Department of Pediatrics and Human Development, Michigan State University, Grand Rapids, MI, United States
| | - Alex J Roy
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Jeffrey R Leipprandt
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
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11
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Misek SA, Newbury PA, Chekalin E, Paithankar S, Doseff AI, Chen B, Gallo KA, Neubig RR. Ibrutinib Blocks YAP1 Activation and Reverses BRAF Inhibitor Resistance in Melanoma Cells. Mol Pharmacol 2022; 101:1-12. [PMID: 34732527 PMCID: PMC11037454 DOI: 10.1124/molpharm.121.000331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 10/01/2021] [Indexed: 11/22/2022] Open
Abstract
Most B-Raf proto-oncogene (BRAF)-mutant melanoma tumors respond initially to BRAF inhibitor (BRAFi)/mitogen-activated protein kinase kinase 1 inhibitor (MEKi) therapy, although few patients have durable long-term responses to these agents. The goal of this study was to use an unbiased computational approach to identify inhibitors that reverse an experimentally derived BRAFi resistance gene expression signature. Using this approach, we found that ibrutinib effectively reverses this signature, and we demonstrate experimentally that ibrutinib resensitizes a subset of BRAFi-resistant melanoma cells to vemurafenib. Ibrutinib is used clinically as an inhibitor of the Src family kinase Bruton tyrosine kinase (BTK); however, neither BTK deletion nor treatment with acalabrutinib, another BTK inhibitor with reduced off-target activity, resensitized cells to vemurafenib. These data suggest that ibrutinib acts through a BTK-independent mechanism in vemurafenib resensitization. To better understand this mechanism, we analyzed the transcriptional profile of ibrutinib-treated BRAFi-resistant melanoma cells and found that the transcriptional profile of ibrutinib was highly similar to that of multiple Src proto-oncogene kinase inhibitors. Since ibrutinib, but not acalabrutinib, has appreciable off-target activity against multiple Src family kinases, it suggests that ibrutinib may be acting through this mechanism. Furthermore, genes that are differentially expressed in ibrutinib-treated cells are enriched in Yes1-associated transcriptional regulator (YAP1) target genes, and we showed that ibrutinib, but not acalabrutinib, reduces YAP1 activity in BRAFi-resistant melanoma cells. Taken together, these data suggest that ibrutinib, or other Src family kinase inhibitors, may be useful for treating some BRAFi/MEKi-refractory melanoma tumors. SIGNIFICANCE STATEMENT: MAPK-targeted therapies provide dramatic initial responses, but resistance develops rapidly; a subset of these tumors may be rendered sensitive again by treatment with an approved Src family kinase inhibitor-ibrutinub-potentially providing improved clinical outcomes.
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Affiliation(s)
- Sean A Misek
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Patrick A Newbury
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Evgenii Chekalin
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Shreya Paithankar
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Andrea I Doseff
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Bin Chen
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Kathleen A Gallo
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
| | - Richard R Neubig
- Departments of Physiology (S.A.M., A.I.D., K.A.G.), Pediatrics and Human Development (P.A.N., E.C., S.P., B.C.), and Pharmacology (A.I.D., B.C., R.R.N.), Michigan State University, East Lansing, Michigan
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12
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Feng H, Larrivee CL, Demireva EY, Xie H, Leipprandt JR, Neubig RR. Retraction: Mouse models of GNAO1-associated movement disorder: Allele- and sex-specific differences in phenotypes. PLoS One 2021; 16:e0258912. [PMID: 34648593 PMCID: PMC8516238 DOI: 10.1371/journal.pone.0258912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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13
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Jia L, Li S, Dai W, Guo L, Xu Z, Scott AM, Zhang Z, Ren J, Zhang Q, Dexheimer TS, Chung-Davidson YW, Neubig RR, Li Q, Li W. Convergent olfactory trace amine-associated receptors detect biogenic polyamines with distinct motifs via a conserved binding site. J Biol Chem 2021; 297:101268. [PMID: 34600890 PMCID: PMC8546428 DOI: 10.1016/j.jbc.2021.101268] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 11/25/2022] Open
Abstract
Biogenic amines activate G-protein-coupled receptors (GPCRs) in the central nervous system in vertebrate animals. Several biogenic amines, when excreted, stimulate trace amine-associated receptors (TAARs), a group of GPCRs in the main olfactory epithelium, and elicit innate behaviors. How TAARs recognize amines with varying numbers of amino groups is largely unknown. We reasoned that a comparison between lamprey and mammalian olfactory TAARs, which are thought to have evolved independently but show convergent responses to polyamines, may reveal structural determinants of amine recognition. Here, we demonstrate that sea lamprey TAAR365 (sTAAR365) responds strongly to biogenic polyamines cadaverine, putrescine, and spermine, and shares a similar response profile as a mammalian TAAR (mTAAR9). Docking and site-directed mutagenesis analyses show that both sTAAR365 and mTAAR9 recognize the two amino groups of cadaverine with the conserved Asp3.32 and Tyr6.51 residues. sTAAR365, which has remarkable sensitivity for cadaverine (EC50 = 4 nM), uses an extra residue, Thr7.42, to stabilize ligand binding. These cadaverine recognition sites also interact with amines with four and three amino groups (spermine and spermidine, respectively). Glu7.36 of sTAAR365 cooperates with Asp3.32 and Thr7.42 to recognize spermine, whereas mTAAR9 recognizes spermidine through an additional aromatic residue, Tyr7.43. These results suggest a conserved mechanism whereby independently evolved TAAR receptors recognize amines with two, three, or four amino groups using the same recognition sites, at which sTAAR365 and mTAAR9 evolved distinct motifs. These motifs interact directly with the amino groups of the polyamines, a class of potent and ecologically important odorants, mediating olfactory signaling.
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Affiliation(s)
- Liang Jia
- Center for Brain Science, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA; College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Shengju Li
- Center for Brain Science, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wenxuan Dai
- Center for Brain Science, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lingna Guo
- Center for Brain Science, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhengrong Xu
- Center for Brain Science, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Otolaryngology Head and Neck Surgery, Jiangsu Provincial Key Medical Discipline (Laboratory), Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China
| | - Anne M Scott
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA
| | - Zhe Zhang
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA
| | - Jianfeng Ren
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Qinghua Zhang
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Thomas S Dexheimer
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, USA
| | - Yu-Wen Chung-Davidson
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA.
| | - Qian Li
- Center for Brain Science, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Research Center for Brain Science and Brain-Inspired Intelligence, Shanghai, China.
| | - Weiming Li
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA.
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14
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Ji Y, Lisabeth EM, Neubig RR. Transforming Growth Factor β1 Increases Expression of Contractile Genes in Human Pulmonary Arterial Smooth Muscle Cells by Potentiating Sphingosine-1-Phosphate Signaling. Mol Pharmacol 2021; 100:53-60. [PMID: 34031187 DOI: 10.1124/molpharm.120.000019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 04/30/2021] [Indexed: 11/22/2022] Open
Abstract
Pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary arterial pressure and carries a very poor prognosis. Understanding of PAH pathogenesis is needed to support the development of new therapeutic strategies. Transforming growth factor β (TGF-β) drives vascular remodeling and increases vascular resistance by regulating differentiation and proliferation of smooth muscle cells (SMCs). Also, sphingosine-1-phosphate (S1P) has been implicated in PAH, but the relation between these two signaling mechanisms is not well understood. Here, we characterize the signaling networks downstream of TGF-β in human pulmonary arterial smooth muscle cells (HPASMCs), which involves mothers against decapentaplegic homolog (SMAD) signaling as well as Rho GTPases. Activation of Rho GTPases regulates myocardin-related transcription factor (MRTF) and serum response factor (SRF) transcription activity and results in upregulation of contractile gene expression. Our genetic and pharmacologic data show that in HPASMCs upregulation of α smooth muscle actin (αSMA) and calponin by TGF-β is dependent on both SMAD and Rho/MRTF-A/SRF transcriptional mechanisms.The kinetics of TGF-β-induced myosin light chain (MLC) 2 phosphorylation, a measure of RhoA activation, are slow, as is regulation of the Rho/MRTF/SRF-induced αSMA expression. These results suggest that TGF-β1 activates Rho/phosphorylated MLC2 through an indirect mechanism, which was confirmed by sensitivity to cycloheximide treatment. As a potential mechanism for this indirect action, TGF-β1 upregulates mRNA for sphingosine kinase (SphK1), the enzyme that produces S1P, an upstream Rho activator, as well as mRNA levels of the S1P receptor (S1PR) 3. SphK1 inhibitor and S1PR3 inhibitors (PF543 and TY52156/VPC23019) reduce TGF-β1-induced αSMA upregulation. Overall, we propose a model in which TGF-β1 activates Rho/MRTF-A/SRF by potentiating an autocrine/paracrine S1P signaling mechanism through SphK1 and S1PR3. SIGNIFICANCE STATEMENT: In human pulmonary arterial smooth muscle cells, transforming growth factor β depends on sphingosine-1-phosphate signaling to bridge the interaction between mothers against decapentaplegic homolog and Rho/myocardin-related transcription factor (MRTF) signaling in regulating α smooth muscle actin (αSMA) expression. The Rho/MRTF pathway is a signaling node in the αSMA regulatory network and is a potential therapeutic target for the treatment of pulmonary arterial hypertension.
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Affiliation(s)
- Yajing Ji
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (Y.J., E.M.L., R.R.N.) and Nicholas V. Perricone, MD, Division of Dermatology, Department of Medicine, College of Human Medicine, East Lansing, Michigan (R.R.N.)
| | - Erika M Lisabeth
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (Y.J., E.M.L., R.R.N.) and Nicholas V. Perricone, MD, Division of Dermatology, Department of Medicine, College of Human Medicine, East Lansing, Michigan (R.R.N.)
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (Y.J., E.M.L., R.R.N.) and Nicholas V. Perricone, MD, Division of Dermatology, Department of Medicine, College of Human Medicine, East Lansing, Michigan (R.R.N.)
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15
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Appleton KM, Palsuledesai CC, Misek SA, Blake M, Zagorski J, Gallo KA, Dexheimer TS, Neubig RR. Inhibition of the Myocardin-Related Transcription Factor Pathway Increases Efficacy of Trametinib in NRAS-Mutant Melanoma Cell Lines. Cancers (Basel) 2021; 13:cancers13092012. [PMID: 33921974 PMCID: PMC8122681 DOI: 10.3390/cancers13092012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/14/2021] [Accepted: 04/14/2021] [Indexed: 12/28/2022] Open
Abstract
Simple Summary Malignant melanoma is the most aggressive skin cancer, and treatment is often ineffective due to the development of resistance to targeted therapeutic agents. The most prevalent form of melanoma with a mutated BRAF gene has an effective treatment, but the second most common mutation in melanoma (NRAS) leads to tumors that lack targeted therapies. In this study, we show that NRAS mutant human melanoma cells that are most resistant to inhibition of the oncogenic pathway have a second activated pathway (Rho). Inhibiting that pathway at one of several points can produce more effective cell killing than inhibition of the NRAS pathway alone. This raises the possibility that such a combination treatment could prove effective in those melanomas that fail to respond to existing targeted therapies such as vemurafenib and trametinib. Abstract The Ras/MEK/ERK pathway has been the primary focus of targeted therapies in melanoma; it is aberrantly activated in almost 80% of human cutaneous melanomas (≈50% BRAFV600 mutations and ≈30% NRAS mutations). While drugs targeting the MAPK pathway have yielded success in BRAFV600 mutant melanoma patients, such therapies have been ineffective in patients with NRAS mutant melanomas in part due to their cytostatic effects and primary resistance. Here, we demonstrate that increased Rho/MRTF-pathway activation correlates with high intrinsic resistance to the MEK inhibitor, trametinib, in a panel of NRAS mutant melanoma cell lines. A combination of trametinib with the Rho/MRTF-pathway inhibitor, CCG-222740, synergistically reduced cell viability in NRAS mutant melanoma cell lines in vitro. Furthermore, the combination of CCG-222740 with trametinib induced apoptosis and reduced clonogenicity in SK-Mel-147 cells, which are highly resistant to trametinib. These findings suggest a role of the Rho/MRTF-pathway in intrinsic trametinib resistance in a subset of NRAS mutant melanoma cell lines and highlight the therapeutic potential of concurrently targeting the Rho/MRTF-pathway and MEK in NRAS mutant melanomas.
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Affiliation(s)
- Kathryn M. Appleton
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA; (K.M.A.); (C.C.P.); (M.B.); (J.Z.); (T.S.D.)
| | - Charuta C. Palsuledesai
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA; (K.M.A.); (C.C.P.); (M.B.); (J.Z.); (T.S.D.)
| | - Sean A. Misek
- Department of Physiology, Michigan State University, East Lansing, MI 48824, USA; (S.A.M.); (K.A.G.)
| | - Maja Blake
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA; (K.M.A.); (C.C.P.); (M.B.); (J.Z.); (T.S.D.)
| | - Joseph Zagorski
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA; (K.M.A.); (C.C.P.); (M.B.); (J.Z.); (T.S.D.)
| | - Kathleen A. Gallo
- Department of Physiology, Michigan State University, East Lansing, MI 48824, USA; (S.A.M.); (K.A.G.)
| | - Thomas S. Dexheimer
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA; (K.M.A.); (C.C.P.); (M.B.); (J.Z.); (T.S.D.)
| | - Richard R. Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA; (K.M.A.); (C.C.P.); (M.B.); (J.Z.); (T.S.D.)
- Department of Medicine, Division of Dermatology, Michigan State University, East Lansing, MI 48824, USA
- Correspondence: ; Tel.: +1-517-353-7145
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16
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Abstract
The COVID-19 pandemic caused by the coronavirus SARS-COV-2 has cost many lives worldwide. In dealing with affected patients, the physician is faced with a very unusual pattern of organ damage that is not easily explained on the basis of prior knowledge of viral-induced pathogenesis. It is established that the main receptor for viral entry into tissues is the protein angiotensin-converting enzyme-2 ["ACE-2", (1)]. In a recent publication (2), a theory of autoimmunity against ACE-2, and/or against the ACE-2/SARS-COV-2 spike protein complex or degradation products thereof, was proposed as a possible explanation for the unusual pattern of organ damage seen in COVID-19. In the light of more recent information, this manuscript expands on the earlier proposed theory and offers additional, testable hypotheses that could explain both the pattern and timeline of organ dysfunction most often observed in COVID-19.
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Affiliation(s)
- Philip McMillan
- Doncaster and Bassetlaw National Health Service (NHS) Trust, Doncaster, United Kingdom
| | - Thomas Dexhiemer
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
| | - Richard R. Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, United States
- Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine, Michigan State University, East Lansing, MI, United States
| | - Bruce D. Uhal
- Department of Physiology, Michigan State University, East Lansing, MI, United States
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17
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Omouessi ST, Leipprandt JR, Akoume MY, Charbeneau R, Wade S, Neubig RR. Mice with an RGS-insensitive Gα i2 protein show growth hormone axis dysfunction. Mol Cell Endocrinol 2021; 521:111098. [PMID: 33278490 DOI: 10.1016/j.mce.2020.111098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/22/2020] [Accepted: 11/26/2020] [Indexed: 01/03/2023]
Abstract
Mice carrying an RGS-insensitive Gαi2 mutation display growth retardation early after birth. Although the growth hormone (GH)-axis is a key endocrine modulator of postnatal growth, its functional state in these mice has not been characterized. The present study was undertaken to address this issue. Results revealed that pituitary mRNA levels for GH, prolactin (PRL), somatostatin (SST), GH-releasing-hormone receptor (GHRH-R) and GH secretagogue receptor (GHS-R) were decreased in mutants compared to controls. These changes were reflected by a significant decrease in plasma levels of GH, IGF-1 and IGF-binding protein-3 (IGFBP-3). Mutants were also less responsive to GHRH and ghrelin (GhL) on GH stimulation of release from pituitary primary cell cultures. In contrast, they were more sensitive to the inhibitory effect of SST. These data provide the first evidence for an alteration of the functional state of the GH-axis in Gαi2G184S mice that likely contributes to their growth retardation.
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MESH Headings
- Animals
- Cells, Cultured
- Female
- GTP-Binding Protein alpha Subunit, Gi2/genetics
- GTP-Binding Protein alpha Subunit, Gi2/metabolism
- Ghrelin/pharmacology
- Growth Disorders/genetics
- Growth Disorders/metabolism
- Growth Hormone/blood
- Growth Hormone/genetics
- Growth Hormone/metabolism
- Growth Hormone-Releasing Hormone/blood
- Growth Hormone-Releasing Hormone/genetics
- Growth Hormone-Releasing Hormone/pharmacology
- Insulin-Like Growth Factor Binding Protein 3/blood
- Insulin-Like Growth Factor Binding Protein 3/genetics
- Insulin-Like Growth Factor I/genetics
- Insulin-Like Growth Factor I/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Mutation
- Pituitary Gland/drug effects
- Pituitary Gland/metabolism
- Prolactin/genetics
- Prolactin/metabolism
- RGS Proteins/genetics
- RGS Proteins/metabolism
- Real-Time Polymerase Chain Reaction
- Receptors, Ghrelin/metabolism
- Receptors, Neuropeptide/genetics
- Receptors, Neuropeptide/metabolism
- Receptors, Pituitary Hormone-Regulating Hormone/genetics
- Receptors, Pituitary Hormone-Regulating Hormone/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Somatostatin/genetics
- Somatostatin/metabolism
- Somatostatin/pharmacology
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Affiliation(s)
- S Thierry Omouessi
- Department of Pharmacology, University of Michigan Medical School, Michigan, USA; Department of Physiology, Faculty of Medicine, Université des Sciences de la Santé (USS) de Libreville, Libreville, Gabon.
| | - Jeffrey R Leipprandt
- Department of Pharmacology and Toxicology, Michigan State University, Michigan, USA
| | - Marie-Yvonne Akoume
- International Research Institute of Biomedical Sciences & Biotechnology-Carles Kambangoye (IRBK), Université Internationale de Libreville, Essassa, Gabon; Viscogliosi Laboratory in Molecular Genetics of Musculoskeletal Diseases, Sainte-Justine University Hospital Research Center, Montréal, Quebec, Canada
| | - Raelene Charbeneau
- Department of Pharmacology, University of Michigan Medical School, Michigan, USA
| | - Susan Wade
- Department of Pharmacology, University of Michigan Medical School, Michigan, USA
| | - Richard R Neubig
- Department of Pharmacology, University of Michigan Medical School, Michigan, USA; Department of Pharmacology and Toxicology, Michigan State University, Michigan, USA
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18
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Misek SA, Appleton KM, Dexheimer TS, Lisabeth EM, Lo RS, Larsen SD, Gallo KA, Neubig RR. Abstract B07: Rho-mediated gene transcription promotes BRAFi resistance in de-differentiated melanoma cells. Cancer Res 2020. [DOI: 10.1158/1538-7445.mel2019-b07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The goal of this study is to identify pharmacologically tractable resistance mechanisms, and ultimately to prevent or reverse drug resistance in melanoma. We demonstrate that a subset of BRAFi-resistant melanoma cell lines showed diminished expression of melanocyte differentiation markers (e.g., Sox10). The transcriptional signature of 15% of treatment-naïve TCGA SKCM (skin cutaneous melanoma) tumors is similar to that of de-differentiated BRAFi-resistant cell lines. This transcriptional signature in BRAFi-resistant melanoma cells and human tumors is associated with increased Rho activation and increased expression of a RhoA/C gene signature. Using a machine learning approach, we predict that these tumors have decreased sensitivity to multiple BRAF/MEK inhibitors, consistent with our observations in multiple cell line models. De-differentiated tumors are predicted to have increased sensitivity to multiple ROCK inhibitors, and this prediction was validated in multiple BRAFi-resistant cell line models. Since ROCK is one of the canonical Rho effector proteins, these data suggest that melanoma cells and tumors with low differentiation characteristics activate the Rho pathway and are sensitive to Rho pathway inhibition. As a consequence of the effect of Rho on the actin cytoskeleton, Rho regulates gene transcription through modulating transcriptional co-activators such as MRTFA and YAP1. Both MRTFA and YAP1 are activated in de-differentiated BRAFi-resistant cells and are predicted to be activated in human tumors with a similar transcriptomic profile. Consistent with our predictions, melanoma cells with MRTFA activation are sensitive to an MRTFA pathway inhibitor and those with high YAP1 activity are sensitive to indirect blockade of YAP1 activation. In total, these results demonstrate that over the course of drug resistance a subset of cells and tumors lose melanocyte lineage characteristics and gain Rho activation. In summary, our work has used bioinformatics/ML approaches to identify Rho-mediated gene transcription as an important, targetable mechanism of BRAFi resistance in de-differentiated melanomas. We experimentally demonstrate the efficacy of this approach in multiple BRAFi-resistant models, highlighting the potential of targeting Rho-mediated transcription for treating drug-resistant melanomas.
Citation Format: Sean A. Misek, Kate M. Appleton, Tom S. Dexheimer, Erika M. Lisabeth, Roger S. Lo, Scott D. Larsen, Kathleen A. Gallo, Richard R. Neubig. Rho-mediated gene transcription promotes BRAFi resistance in de-differentiated melanoma cells [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr B07.
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Affiliation(s)
| | | | | | | | - Roger S. Lo
- 2University of California, Los Angeles, Los Angeles, CA,
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19
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Zhang Z, Zhang Q, Dexheimer TS, Ren J, Neubig RR, Li W. Two highly related odorant receptors specifically detect α-bile acid pheromones in sea lamprey ( Petromyzon marinus). J Biol Chem 2020; 295:12153-12166. [PMID: 32636305 PMCID: PMC7443511 DOI: 10.1074/jbc.ra119.011532] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 07/01/2020] [Indexed: 10/23/2022] Open
Abstract
Pheromones play critical roles in habitat identification and reproductive behavior synchronization in the sea lamprey (Petromyzon marinus). The bile acid 3-keto petromyzonol sulfate (3kPZS) is a major component of the sex pheromone mixture from male sea lamprey that induces specific olfactory and behavioral responses in conspecific individuals. Olfactory receptors interact directly with pheromones, which is the first step in their detection, but identifying the cognate receptors of specific pheromones is often challenging. Here, we deorphanized two highly related odorant receptors (ORs), OR320a and OR320b, of P. marinus that respond to 3kPZS. In a heterologous expression system coupled to a cAMP-responsive CRE-luciferase, OR320a and OR320b specifically responded to C24 5α-bile acids, and both receptors were activated by the same set of 3kPZS analogs. OR320a displayed larger responses to all 3kPZS analogs than did OR320b. This difference appeared to be largely determined by a single amino acid residue, Cys-792.56, the C-terminal sixth residue relative to the most conserved residue in the second transmembrane domain (2.56) of OR320a. This region of TM2 residues 2.56-2.60 apparently is critical for the detection of steroid compounds by odorant receptors in lamprey, zebrafish, and humans. Finally, we identified OR320 orthologs in Japanese lamprey (Lethenteron camtschaticum), suggesting that the OR320 family may be widely present in lamprey species and that OR320 may be under purifying selection. Our results provide a system to examine the origin of olfactory steroid detection in vertebrates and to define a highly conserved molecular mechanism for steroid-ligand detection by G protein-coupled receptors.
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Affiliation(s)
- Zhe Zhang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China; International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China; Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution, Shanghai Ocean University, Shanghai, China
| | - Qinghua Zhang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China; International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China; Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution, Shanghai Ocean University, Shanghai, China
| | - Thomas S Dexheimer
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Jianfeng Ren
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, China; International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai, China; Shanghai Universities Key Laboratory of Marine Animal Taxonomy and Evolution, Shanghai Ocean University, Shanghai, China
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA.
| | - Weiming Li
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA.
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20
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Larrivee CL, Feng H, Quinn JA, Shaw VS, Leipprandt JR, Demireva EY, Xie H, Neubig RR. Mice with GNAO1 R209H Movement Disorder Variant Display Hyperlocomotion Alleviated by Risperidone. J Pharmacol Exp Ther 2020; 373:24-33. [PMID: 31907305 DOI: 10.1124/jpet.119.262733] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 12/27/2019] [Indexed: 11/22/2022] Open
Abstract
Neurodevelopmental disorder with involuntary movements (Online Mendelian Inheritance in Man: 617493) is a severe, early onset neurologic condition characterized by a delay in psychomotor development, hypotonia, and hyperkinetic involuntary movements. Heterozygous de novo mutations in the GNAO1 gene cause neurodevelopmental disorder with involuntary movements. Gα o, the gene product of GNAO1, is the alpha subunit of Go, a member of the heterotrimeric Gi/o family of G proteins. Go is found abundantly throughout the brain, but the pathophysiological mechanisms linking Gα o functions to clinical manifestations of GNAO1-related disorders are still poorly understood. One of the most common mutant alleles among the GNAO1 encephalopathies is the c.626G>A or p.Arg209His (R209H) mutation. We developed heterozygous knock-in Gnao1 +/R209H mutant mice using CRISPR/Cas9 methodology to assess whether a mouse model could replicate aspects of the neurodevelopmental disorder with involuntary movements clinical pattern. Mice carrying the R209H mutation exhibited increased locomotor activity and a modest gait abnormality at 8-12 weeks. In contrast to mice carrying other mutations in Gnao1, the Gnao1 +/R209H mice did not show enhanced seizure susceptibility. Levels of protein expression in multiple brain regions were unchanged from wild-type (WT) mice, but the nucleotide exchange rate of mutant R209H Gα o was 6.2× faster than WT. The atypical neuroleptic risperidone has shown efficacy in a patient with the R209H mutation. It also alleviated the hyperlocomotion phenotype observed in our mouse model but suppressed locomotion in WT mice as well. In this study, we show that Gnao1 +/R209H mice mirror elements of the patient phenotype and respond to an approved pharmacological agent. SIGNIFICANCE STATEMENT: Children with de novo mutations in the GNAO1 gene may present with movement disorders with limited effective therapeutic options. The most common mutant variant seen in children with GNAO1-associated movement disorder is R209H. Here we show, using a novel Gnao1 +/R209H mouse, that there is a clear behavioral phenotype that is suppressed by risperidone. However, risperidone also affects wild-type mouse activity, so its effects are not selective for the GNAO1-associated movement disorder.
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Affiliation(s)
- Casandra L Larrivee
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Huijie Feng
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Josiah A Quinn
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Vincent S Shaw
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Jeffrey R Leipprandt
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Elena Y Demireva
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Huirong Xie
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
| | - Richard R Neubig
- Department of Comparative Medicine and Integrative Biology (C.L.L.), Department of Pharmacology and Toxicology (C.L.L., H.F., J.A.Q., V.S.S., J.R.L., R.R.N.), Transgenic and Genome Editing Facility, Institute for Quantitative Health Science and Engineering (E.Y.D., H.X.), and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan
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21
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Misek SA, Appleton KM, Dexheimer TS, Lisabeth EM, Lo RS, Larsen SD, Gallo KA, Neubig RR. Rho-mediated signaling promotes BRAF inhibitor resistance in de-differentiated melanoma cells. Oncogene 2019; 39:1466-1483. [PMID: 31659259 PMCID: PMC7024013 DOI: 10.1038/s41388-019-1074-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 09/25/2019] [Accepted: 10/14/2019] [Indexed: 01/04/2023]
Abstract
Over half of cutaneous melanoma tumors have BRAFV600E/K mutations. Acquired resistance to BRAF inhibitors (BRAFi) remains a major hurdle in attaining durable therapeutic responses. In this study we demonstrate that approximately 50–60% of melanoma cell lines with vemurafenib resistance acquired in vitro show activation of RhoA family GTPases. In BRAFi-resistant melanoma cell lines and tumors, activation of RhoA is correlated with decreased expression of melanocyte lineage genes. Using a machine learning approach, we built gene expression-based models to predict drug sensitivity for 265 common anti-cancer compounds. We then projected these signatures onto the collection of TCGA cutaneous melanoma and found that poorly differentiated tumors were predicted to have increased sensitivity to multiple Rho kinase (ROCK) inhibitors. Two transcriptional effectors downstream of Rho, MRTF and YAP1, are activated in the RhoHigh BRAFi-resistant cell lines, and resistant cells are more sensitive to inhibition of these transcriptional mechanisms. Taken together, these results support the concept of targeting Rho-regulated gene transcription pathways as a promising therapeutic approach to restore sensitivity to BRAFi-resistant tumors or as a combination therapy to prevent the onset of drug resistance.
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Affiliation(s)
- S A Misek
- Department of Physiology, Michigan State University, East Lansing, MI, 48824, USA
| | - K M Appleton
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - T S Dexheimer
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - E M Lisabeth
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - R S Lo
- Division of Dermatology, Department of Medicine, University of California, Los Angeles, CA, 90095, USA.,Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, 90095, USA.,Jonsson Comprehensive Cancer Center, University of California, Los Angeles, CA, 90095, USA.,David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - S D Larsen
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA.,Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI, 48109, USA
| | - K A Gallo
- Department of Physiology, Michigan State University, East Lansing, MI, 48824, USA
| | - R R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, 48824, USA. .,Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine, College of Human Medicine, Michigan State University, East Lansing, 48824, MI, USA.
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22
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Phan HTN, Jackson WF, Shaw VS, Watts SW, Neubig RR. Loss-of-Function Mutations in Human Regulator of G Protein Signaling RGS2 Differentially Regulate Pharmacological Reactivity of Resistance Vasculature. Mol Pharmacol 2019; 96:826-834. [PMID: 31645376 DOI: 10.1124/mol.119.116822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 10/03/2019] [Indexed: 12/21/2022] Open
Abstract
Regulator of G protein signaling 2 (RGS2) plays a role in reducing vascular contraction and promoting relaxation due to its GTPase accelerating protein activity toward Gαq. Previously, we identified four human loss-of-function (LOF) mutations in RGS2 (Q2L, D40Y, R44H, and R188H). This study aimed to investigate whether those RGS2 LOF mutations disrupt the ability of RGS2 to regulate vascular reactivity. Isolated mesenteric arteries (MAs) from RGS2-/- mice showed an elevated contractile response to 5 nM angiotensin II and a loss of acetylcholine (ACh)-mediated vasodilation. Reintroduction of a wild-type (WT) RGS2-GFP plasmid into RGS2-/- MAs suppressed the vasoconstrictor response to angiotensin II. RGS2 LOF mutants failed to suppress the angiotensin II constriction response compared with RGS2 WT. In contrast, ACh-mediated vasoconstriction was restored by expression of RGS2 WT, D40Y, and R44H but not by RGS2 Q2L or R188H. Phosphorylation of RGS2 D40Y and R44H by protein kinase G (PKG) may explain their maintained function to support relaxation in MAs. This is supported by phosphomimetic mutants and suppression of vasorelaxation mediated by RGS2 D40Y by a PKG inhibitor. These results demonstrate that RGS2 attenuates vasoconstriction in MAs and that RGS2 LOF mutations cannot carry out this effect. Among them, the Q2L and R188H mutants supported less relaxation to ACh, whereas relaxation mediated by the D40Y and R44H mutant proteins was equal to that with WT protein. Phosphorylation of RGS2 by PKG appears to contribute to this vasorelaxation. These results provide insights for precision medicine targeting the rare individuals carrying these RGS2 mutations. SIGNIFICANCE STATEMENT: Regulator of G protein signaling 2 (RGS2) has been implicated in the control of blood pressure; rare mutations in the RGS2 gene have been identified in large-scale human gene sequencing studies. Four human mutations in RGS2 that cause loss of function (LOF) in cell-based assays were examined in isolated mouse arteries for effects on both vasoconstriction and vasodilation. All mutants showed the expected LOF effects in suppressing vasoconstriction. Surprisingly, the D40Y and R44H mutant RGS2 showed normal control of vasodilation. We propose that this is due to rescue of the mislocalization phenotype of these two mutants by nitric oxide-mediated/protein kinase G-dependent phosphorylation. These mechanisms may guide drug discovery or drug repurposing efforts for hypertension by enhancing RGS2 function.
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Affiliation(s)
- Hoa T N Phan
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (H.T.N.P., W.F.J., V.S.S., S.W.W., R.R.N.)
| | - William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (H.T.N.P., W.F.J., V.S.S., S.W.W., R.R.N.)
| | - Vincent S Shaw
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (H.T.N.P., W.F.J., V.S.S., S.W.W., R.R.N.)
| | - Stephanie W Watts
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (H.T.N.P., W.F.J., V.S.S., S.W.W., R.R.N.)
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (H.T.N.P., W.F.J., V.S.S., S.W.W., R.R.N.)
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23
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Shaw VS, Mohammadi M, Quinn JA, Vashisth H, Neubig RR. An Interhelical Salt Bridge Controls Flexibility and Inhibitor Potency for Regulators of G-protein Signaling Proteins 4, 8, and 19. Mol Pharmacol 2019; 96:683-691. [PMID: 31543506 DOI: 10.1124/mol.119.117176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/14/2019] [Indexed: 12/13/2022] Open
Abstract
Regulators of G-protein signaling (RGS) proteins modulate receptor signaling by binding to activated G-protein α-subunits, accelerating GTP hydrolysis. Selective inhibition of RGS proteins increases G-protein activity and may provide unique tissue specificity. Thiadiazolidinones (TDZDs) are covalent inhibitors that act on cysteine residues to inhibit RGS4, RGS8, and RGS19. There is a correlation between protein flexibility and potency of inhibition by the TDZD 4-[(4- fluorophenyl)methyl]-2-(4-methylphenyl)-1,2,4-thiadiazolidine-3,5-dione (CCG-50014). In the context of a single conserved cysteine residue on the α 4 helix, RGS19 is the most flexible and most potently inhibited by CCG-50014, followed by RGS4 and RGS8. In this work, we identify residues responsible for differences in both flexibility and potency of inhibition among RGS isoforms. RGS19 lacks a charged residue on the α 4 helix that is present in RGS4 and RGS8. Introducing a negative charge at this position (L118D) increased the thermal stability of RGS19 and decreased the potency of inhibition of CCG-50014 by 8-fold. Mutations eliminating salt bridge formation in RGS8 and RGS4 decreased thermal stability in RGS8 and increased potency of inhibition of both RGS4 and RGS8 by 4- and 2-fold, respectively. Molecular dynamics simulations with an added salt bridge in RGS19 (L118D) showed reduced RGS19 flexibility. Hydrogen-deuterium exchange studies showed striking differences in flexibility in the α 4 helix of RGS4, 8, and 19 with salt bridge-modifying mutations. These results show that the α 4 salt bridge-forming residue controls flexibility in several RGS isoforms and supports a causal relationship between RGS flexibility and the potency of TDZD inhibitors. SIGNIFICANCE STATEMENT: Inhibitor potency is often viewed in relation to the static structure of a target protein binding pocket. Using both experimental and computation studies we assess determinants of dynamics and inhibitor potency for three different RGS proteins. A single salt bridge-forming residue determines differences in flexibility between RGS isoforms; mutations either increase or decrease protein motion with correlated alterations in inhibitor potency. This strongly suggests a causal relationship between RGS protein flexibility and covalent inhibitor potency.
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Affiliation(s)
- Vincent S Shaw
- Department of Pharmacology and Toxicology (V.S.S., J.A.Q., R.R.N.) and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan; and Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire (M.M., H.V.)
| | - Mohammadjavad Mohammadi
- Department of Pharmacology and Toxicology (V.S.S., J.A.Q., R.R.N.) and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan; and Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire (M.M., H.V.)
| | - Josiah A Quinn
- Department of Pharmacology and Toxicology (V.S.S., J.A.Q., R.R.N.) and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan; and Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire (M.M., H.V.)
| | - Harish Vashisth
- Department of Pharmacology and Toxicology (V.S.S., J.A.Q., R.R.N.) and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan; and Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire (M.M., H.V.)
| | - Richard R Neubig
- Department of Pharmacology and Toxicology (V.S.S., J.A.Q., R.R.N.) and Nicholas V. Perricone, M.D., Division of Dermatology, Department of Medicine (R.R.N.), Michigan State University, East Lansing, Michigan; and Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire (M.M., H.V.)
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24
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Scott AM, Zhang Z, Jia L, Li K, Zhang Q, Dexheimer T, Ellsworth E, Ren J, Chung-Davidson YW, Zu Y, Neubig RR, Li W. Spermine in semen of male sea lamprey acts as a sex pheromone. PLoS Biol 2019; 17:e3000332. [PMID: 31287811 PMCID: PMC6615597 DOI: 10.1371/journal.pbio.3000332] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 06/03/2019] [Indexed: 12/19/2022] Open
Abstract
Semen is fundamental for sexual reproduction. The non-sperm part of ejaculated semen, or seminal plasma, facilitates the delivery of sperm to the eggs. The seminal plasma of some species with internal fertilization contains anti-aphrodisiac molecules that deter promiscuity in post-copulatory females, conferring fitness benefits to the ejaculating male. By contrast, in some taxa with external fertilization such as fish, exposure to semen promotes spawning behaviors. However, no specific compounds in semen have been identified as aphrodisiac pheromones. We sought to identify a pheromone from the milt (fish semen) of sea lamprey (Petromyzon marinus), a jawless fish that spawns in lek-like aggregations in which each spermiating male defends a nest, and ovulatory females move from nest to nest to mate. We postulated that milt compounds signal to ovulatory females the presence of spawning spermiating males. We determined that spermine, an odorous polyamine initially identified from human semen, is indeed a milt pheromone. At concentrations as low as 10-14 molar, spermine stimulated the lamprey olfactory system and attracted ovulatory females but did not attract males or pre-ovulatory females. We found spermine activated a trace amine-associated receptor (TAAR)-like receptor in the lamprey olfactory epithelium. A novel antagonist to that receptor nullified the attraction of ovulatory females to spermine. Our results elucidate a mechanism whereby a seminal plasma pheromone attracts ready-to-mate females and implicates a possible conservation of the olfactory detection of semen from jawless vertebrates to humans. Milt pheromones may also have management implications for sea lamprey populations.
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Affiliation(s)
- Anne M. Scott
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
| | - Zhe Zhang
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Liang Jia
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
| | - Ke Li
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
| | - Qinghua Zhang
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Thomas Dexheimer
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, United States of America
| | - Edmund Ellsworth
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, United States of America
| | - Jianfeng Ren
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Yu-Wen Chung-Davidson
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
| | - Yao Zu
- College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai, China
| | - Richard R. Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, United States of America
- * E-mail: (RRN); (WL)
| | - Weiming Li
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
- * E-mail: (RRN); (WL)
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Lionarons DA, Hancock DC, Rana S, East P, Moore C, Murillo MM, Carvalho J, Spencer-Dene B, Herbert E, Stamp G, Damry D, Calado DP, Rosewell I, Fritsch R, Neubig RR, Molina-Arcas M, Downward J. RAC1 P29S Induces a Mesenchymal Phenotypic Switch via Serum Response Factor to Promote Melanoma Development and Therapy Resistance. Cancer Cell 2019; 36:68-83.e9. [PMID: 31257073 PMCID: PMC6617390 DOI: 10.1016/j.ccell.2019.05.015] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 03/25/2019] [Accepted: 05/24/2019] [Indexed: 01/14/2023]
Abstract
RAC1 P29 is the third most commonly mutated codon in human cutaneous melanoma, after BRAF V600 and NRAS Q61. Here, we study the role of RAC1P29S in melanoma development and reveal that RAC1P29S activates PAK, AKT, and a gene expression program initiated by the SRF/MRTF transcriptional pathway, which results in a melanocytic to mesenchymal phenotypic switch. Mice with ubiquitous expression of RAC1P29S from the endogenous locus develop lymphoma. When expressed only in melanocytes, RAC1P29S cooperates with oncogenic BRAF or with NF1-loss to promote tumorigenesis. RAC1P29S also drives resistance to BRAF inhibitors, which is reversed by SRF/MRTF inhibitors. These findings establish RAC1P29S as a promoter of melanoma initiation and mediator of therapy resistance, while identifying SRF/MRTF as a potential therapeutic target.
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Affiliation(s)
- Daniël A Lionarons
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - David C Hancock
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Sareena Rana
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Lung Cancer Group, Division of Molecular Pathology, Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
| | - Philip East
- Bioinformatics & Biostatistics, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Christopher Moore
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Miguel M Murillo
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Lung Cancer Group, Division of Molecular Pathology, Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
| | - Joana Carvalho
- Experimental Histopathology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Bradley Spencer-Dene
- Experimental Histopathology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Eleanor Herbert
- Experimental Histopathology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Royal Veterinary College, Hatfield AL9 7TA, UK
| | - Gordon Stamp
- Experimental Histopathology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Djamil Damry
- Immunity & Cancer Laboratories, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Dinis P Calado
- Immunity & Cancer Laboratories, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Ian Rosewell
- Genetic Manipulation Service, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Ralph Fritsch
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Universitätsklinikum Freiburg, Freiburg 79106, Germany
| | | | - Miriam Molina-Arcas
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
| | - Julian Downward
- Oncogene Biology, Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Lung Cancer Group, Division of Molecular Pathology, Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK.
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26
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Leal AS, Misek SA, Lisabeth EM, Neubig RR, Liby KT. The Rho/MRTF pathway inhibitor CCG-222740 reduces stellate cell activation and modulates immune cell populations in Kras G12D; Pdx1-Cre (KC) mice. Sci Rep 2019; 9:7072. [PMID: 31068602 PMCID: PMC6506531 DOI: 10.1038/s41598-019-43430-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 04/24/2019] [Indexed: 12/18/2022] Open
Abstract
The stromal reaction in pancreatic cancer creates a physical barrier that blocks therapeutic intervention and creates an immunosuppressive tumor microenvironment. The Rho/myocardin-related transcription factor (MRTF) pathway is implicated in the hyper-activation of fibroblasts in fibrotic diseases and the activation of pancreatic stellate cells. In this study we use CCG-222740, a small molecule, designed as a Rho/MRTF pathway inhibitor. This compound decreases the activation of stellate cells in vitro and in vivo, by reducing the levels of alpha smooth muscle actin (α-SMA) expression. CCG-222740 also modulates inflammatory components of the pancreas in KC mice (LSL-KrasG12D/+; Pdx-1-Cre) stimulated with caerulein. It decreases the infiltration of macrophages and increases CD4 T cells and B cells. Analysis of the pancreatic adenocarcinoma (PDA) TCGA dataset revealed a correlation between elevated RhoA, RhoC and MRTF expression and decreased survival in PDA patients. Moreover, a MRTF signature is correlated with a Th2 cell signature in human PDA tumors.
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Affiliation(s)
- Ana S Leal
- Michigan State University, Department of Pharmacology & Toxicology, East Lansing, MI, USA
| | | | - Erika M Lisabeth
- Michigan State University, Department of Pharmacology & Toxicology, East Lansing, MI, USA
| | - Richard R Neubig
- Michigan State University, Department of Pharmacology & Toxicology, East Lansing, MI, USA
| | - Karen T Liby
- Michigan State University, Department of Pharmacology & Toxicology, East Lansing, MI, USA.
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27
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Kahl DJ, Hutchings KM, Lisabeth EM, Haak AJ, Leipprandt JR, Dexheimer T, Khanna D, Tsou PS, Campbell PL, Fox DA, Wen B, Sun D, Bailie M, Neubig RR, Larsen SD. 5-Aryl-1,3,4-oxadiazol-2-ylthioalkanoic Acids: A Highly Potent New Class of Inhibitors of Rho/Myocardin-Related Transcription Factor (MRTF)/Serum Response Factor (SRF)-Mediated Gene Transcription as Potential Antifibrotic Agents for Scleroderma. J Med Chem 2019; 62:4350-4369. [PMID: 30951312 DOI: 10.1021/acs.jmedchem.8b01772] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Through a phenotypic high-throughput screen using a serum response element luciferase promoter, we identified a novel 5-aryl-1,3,4-oxadiazol-2-ylthiopropionic acid lead inhibitor of Rho/myocardin-related transcription factor (MRTF)/serum response factor (SRF)-mediated gene transcription with good potency (IC50 = 180 nM). We were able to rapidly improve the cellular potency by 5 orders of magnitude guided by sharply defined and synergistic SAR. The remarkable potency and depth of the SAR, as well as the relatively low molecular weight of the series, suggests, but does not prove, that binding to the unknown molecular target may be occurring through a covalent mechanism. The series nevertheless has no observable cytotoxicity up to 100 μM. Ensuing pharmacokinetic optimization resulted in the development of two potent and orally bioavailable anti-fibrotic agents that were capable of dose-dependently reducing connective tissue growth factor gene expression in vitro as well as significantly reducing the development of bleomycin-induced dermal fibrosis in mice in vivo.
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Affiliation(s)
| | | | - Erika Mathes Lisabeth
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Andrew J Haak
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Jeffrey R Leipprandt
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Thomas Dexheimer
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Dinesh Khanna
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - Pei-Suen Tsou
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - Phillip L Campbell
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | - David A Fox
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence , University of Michigan Medical Center , Ann Arbor , Michigan 48109 , United States
| | | | | | - Marc Bailie
- Michigan State University in Vivo Facility , East Lansing , Michigan 48824 , United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48824 , United States
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Shaw VS, Quinn JA, Mohammadi M, Vashisth H, Neubig RR. A Salt Bridge between α4 and α5 Helices Drives Differences in Flexibility and Potency of Inhibition among Regulator of G‐protein Signaling (RGS) Proteins. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.784.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Vincent S Shaw
- Pharmacology and ToxicologyMichigan State UniversityLansingMI
| | - Josiah A Quinn
- Pharmacology and ToxicologyMichigan State UniversityLansingMI
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Lisabeth EM, Kahl D, Gopallawa I, Haynes SE, Misek SA, Campbell PL, Dexheimer TS, Khanna D, Fox DA, Jin X, Martin BR, Larsen SD, Neubig RR. Identification of Pirin as a Molecular Target of the CCG-1423/CCG-203971 Series of Antifibrotic and Antimetastatic Compounds. ACS Pharmacol Transl Sci 2019; 2:92-100. [PMID: 32039344 DOI: 10.1021/acsptsci.8b00048] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A series of compounds (including CCG-1423 and CCG-203971) discovered through an MRTF/SRF-dependent luciferase screen has shown remarkable efficacy in a variety of in vitro and in vivo models, including significant reduction of melanoma metastasis and bleomycin- induced fibrosis. Although these compounds are efficacious in these disease models, the molecular target is unknown. Here, we describe affinity isolation-based target identification efforts which yielded pirin, an iron-dependent cotranscription factor, as a target of this series of compounds. Using biophysical techniques including isothermal titration calorimetry and X-ray crystallography, we verify that pirin binds these compounds in vitro. We also show with genetic approaches that pirin modulates MRTF- dependent luciferase reporter activity. Finally, using both siRNA and a previously validated pirin inhibitor, we show a role for pirin in TGF-β- induced gene expression in primary dermal fibroblasts. A recently developed analog, CCG-257081, which co crystallizes with pirin, is also effective in the prevention of bleomycin-induced dermal fibrosis.
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Affiliation(s)
- Erika M Lisabeth
- Department of Pharmacology & Toxicology and Michigan State University, East Lansing, Michigan, 48824, United States
| | - Dylan Kahl
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Indiwari Gopallawa
- Department of Pharmacology & Toxicology and Michigan State University, East Lansing, Michigan, 48824, United States
| | - Sarah E Haynes
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Sean A Misek
- Department of Pharmacology & Toxicology and Michigan State University, East Lansing, Michigan, 48824, United States
| | - Phillip L Campbell
- Department of Internal Medicine, Division of Rheumatology, and University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Thomas S Dexheimer
- Department of Pharmacology & Toxicology and Michigan State University, East Lansing, Michigan, 48824, United States
| | - Dinesh Khanna
- Department of Internal Medicine, Division of Rheumatology, and University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - David A Fox
- Department of Internal Medicine, Division of Rheumatology, and University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Xiangshu Jin
- Department of Biochemistry, Michigan State University, East Lansing, Michigan, 48824, United States
| | - Brent R Martin
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Scott D Larsen
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, United States.,Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, Michigan, 48109, United States
| | - Richard R Neubig
- Department of Pharmacology & Toxicology and Michigan State University, East Lansing, Michigan, 48824, United States
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Mohammadi M, Mohammadiarani H, Shaw VS, Neubig RR, Vashisth H. Cover Image, Volume 87, Issue 2. Proteins 2019. [DOI: 10.1002/prot.25633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | | | - Vincent S. Shaw
- Department of Pharmacology and Toxicology; Michigan State University; East Lansing Michigan
| | - Richard R. Neubig
- Department of Pharmacology and Toxicology; Michigan State University; East Lansing Michigan
| | - Harish Vashisth
- Department of Chemical Engineering; University of New Hampshire; Durham New Hampshire
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Sumit M, Jovic A, Neubig RR, Takayama S, Linderman JJ. A Two-Pulse Cellular Stimulation Test Elucidates Variability and Mechanisms in Signaling Pathways. Biophys J 2019; 116:962-973. [PMID: 30782397 DOI: 10.1016/j.bpj.2019.01.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/14/2019] [Accepted: 01/18/2019] [Indexed: 12/14/2022] Open
Abstract
Mammalian cells respond in a variable manner when provided with physiological pulses of ligand, such as low concentrations of acetylcholine present for just tens of seconds or TNFα for just tens of minutes. For a two-pulse stimulation, some cells respond to both pulses, some do not respond, and yet others respond to only one or the other pulse. Are these different response patterns the result of the small number of ligands being able to only stochastically activate the pathway at random times or an output pattern from a deterministic algorithm responding differently to different stimulation intervals? If the response is deterministic in nature, what parameters determine whether a response is generated or skipped? To answer these questions, we developed a two-pulse test that utilizes different rest periods between stimulation pulses. This "rest-period test" revealed that cells skip responses predictably as the rest period is shortened. By combining these experimental results with a mathematical model of the pathway, we further obtained mechanistic insight into potential sources of response variability. Our analysis indicates that in both intracellular calcium and NFκB signaling, response variability is consistent with extrinsic noise (cell-to-cell variability in protein levels), a short-term memory of stimulation, and high Hill coefficient processes. Furthermore, these results support recent works that have emphasized the role of deterministic processes for explaining apparently stochastic cellular response variability and indicate that even weak stimulations likely guide mammalian cells to appropriate fates rather than leaving outcomes to chance. We envision that the rest-period test can be applied to other signaling pathways to extract mechanistic insight.
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Affiliation(s)
- Madhuresh Sumit
- Biophysics Graduate Program, University of Michigan, Ann Arbor, Michigan
| | - Andreja Jovic
- Program in Molecular Pharmacology, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Shuichi Takayama
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia.
| | - Jennifer J Linderman
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan; Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan.
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Feng H, Larrivee CL, Demireva EY, Xie H, Leipprandt JR, Neubig RR. Mouse models of GNAO1-associated movement disorder: Allele- and sex-specific differences in phenotypes. PLoS One 2019; 14:e0211066. [PMID: 30682176 PMCID: PMC6347370 DOI: 10.1371/journal.pone.0211066] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 01/07/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Infants and children with dominant de novo mutations in GNAO1 exhibit movement disorders, epilepsy, or both. Children with loss-of-function (LOF) mutations exhibit Epileptiform Encephalopathy 17 (EIEE17). Gain-of-function (GOF) mutations or those with normal function are found in patients with Neurodevelopmental Disorder with Involuntary Movements (NEDIM). There is no animal model with a human mutant GNAO1 allele. OBJECTIVES Here we develop a mouse model carrying a human GNAO1 mutation (G203R) and determine whether the clinical features of patients with this GNAO1 mutation, which includes both epilepsy and movement disorder, would be evident in the mouse model. METHODS A mouse Gnao1 knock-in GOF mutation (G203R) was created by CRISPR/Cas9 methods. The resulting offspring and littermate controls were subjected to a battery of behavioral tests. A previously reported GOF mutant mouse knock-in (Gnao1+/G184S), which has not been found in patients, was also studied for comparison. RESULTS Gnao1+/G203R mutant mice are viable and gain weight comparably to controls. Homozygotes are non-viable. Grip strength was decreased in both males and females. Male Gnao1+/G203R mice were strongly affected in movement assays (RotaRod and DigiGait) while females were not. Male Gnao1+/G203R mice also showed enhanced seizure propensity in the pentylenetetrazole kindling test. Mice with a G184S GOF knock-in also showed movement-related behavioral phenotypes but females were more strongly affected than males. CONCLUSIONS Gnao1+/G203R mice phenocopy children with heterozygous GNAO1 G203R mutations, showing both movement disorder and a relatively mild epilepsy pattern. This mouse model should be useful in mechanistic and preclinical studies of GNAO1-related movement disorders.
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Affiliation(s)
- Huijie Feng
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, United States of America
| | - Casandra L. Larrivee
- College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States of America
| | - Elena Y. Demireva
- Transgenic and Genome Editing Facility, Michigan State University, East Lansing, MI, United States of America
| | - Huirong Xie
- Transgenic and Genome Editing Facility, Michigan State University, East Lansing, MI, United States of America
| | - Jeff R. Leipprandt
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, United States of America
| | - Richard R. Neubig
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, United States of America
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33
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Mohammadi M, Mohammadiarani H, Shaw VS, Neubig RR, Vashisth H. Interplay of cysteine exposure and global protein dynamics in small-molecule recognition by a regulator of G-protein signaling protein. Proteins 2018; 87:146-156. [PMID: 30521141 DOI: 10.1002/prot.25642] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/07/2018] [Accepted: 11/29/2018] [Indexed: 02/06/2023]
Abstract
Regulator of G protein signaling (RGS) proteins play a pivotal role in regulation of G protein-coupled receptor (GPCR) signaling and are therefore becoming an increasingly important therapeutic target. Recently discovered thiadiazolidinone (TDZD) compounds that target cysteine residues have shown different levels of specificities and potencies for the RGS4 protein, thereby suggesting intrinsic differences in dynamics of this protein upon binding of these compounds. In this work, we investigated using atomistic molecular dynamics (MD) simulations the effect of binding of several small-molecule inhibitors on perturbations and dynamical motions in RGS4. Specifically, we studied two conformational models of RGS4 in which a buried cysteine residue is solvent-exposed due to side-chain motions or due to flexibility in neighboring helices. We found that TDZD compounds with aromatic functional groups perturb the RGS4 structure more than compounds with aliphatic functional groups. Moreover, small-molecules with aromatic functional groups but lacking sulfur atoms only transiently reside within the protein and spontaneously dissociate to the solvent. We further measured inhibitory effects of TDZD compounds using a protein-protein interaction assay on a single-cysteine RGS4 protein showing trends in potencies of compounds consistent with our simulation studies. Thermodynamic analyses of RGS4 conformations in the apo-state and on binding to TDZD compounds revealed links between both conformational models of RGS4. The exposure of cysteine side-chains appears to facilitate initial binding of TDZD compounds followed by migration of the compound into a bundle of four helices, thereby causing allosteric perturbations in the RGS/Gα protein-protein interface.
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Affiliation(s)
| | | | - Vincent S Shaw
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Harish Vashisth
- Department of Chemical Engineering, University of New Hampshire, Durham, New Hampshire
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Mohammadiarani H, Shaw VS, Neubig RR, Vashisth H. Interpreting Hydrogen-Deuterium Exchange Events in Proteins Using Atomistic Simulations: Case Studies on Regulators of G-Protein Signaling Proteins. J Phys Chem B 2018; 122:9314-9323. [PMID: 30222348 PMCID: PMC6430106 DOI: 10.1021/acs.jpcb.8b07494] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Hydrogen-deuterium exchange (HDX) experiments are widely used in studies of protein dynamics. To predict the propensity of amide hydrogens for exchange with deuterium, several models have been reported in which computations of amide-hydrogen protection factors are carried out using molecular dynamics (MD) simulations. Given significant variation in the criteria used in different models, the robustness and broader applicability of these models to other proteins, especially homologous proteins showing distinct amide-exchange patterns, remains unknown. The sensitivity of the predictions when MD simulations are conducted with different force-fields is yet to tested and quantified. Using MD simulations and experimental HDX data on three homologous signaling proteins, we report detailed studies quantifying the performance of seven previously reported models (M1-M7) of two general types: empirical and fractional-population models. We find that the empirical models show inconsistent predictions but predictions of the fractional population models are robust. Contrary to previously reported work, we find that the solvent-accessible surface area of amide hydrogens is a useful metric when combined with a new metric defining the distances of amide hydrogens from the first polar atoms in proteins. On the basis of this, we report two new models, one empirical (M8) and one population-based (M9). We find strong protection of amide hydrogens from solvent exchange both within the stable helical motifs and also in the interhelical loops. We further observe that the exchange-competent states of amide hydrogens occur on the sub 100 ps time-scale via localized fluctuations, and such states among amides of a given protein do not appear to show any cooperativity or allosteric coupling.
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Affiliation(s)
- Hossein Mohammadiarani
- Department of Chemical Engineering , University of New Hampshire , Durham , New Hampshire 03824 , United States
| | - Vincent S Shaw
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48825 , United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48825 , United States
| | - Harish Vashisth
- Department of Chemical Engineering , University of New Hampshire , Durham , New Hampshire 03824 , United States
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35
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Misek SA, Gallo KA, Neubig RR. Abstract 5895: Targeting RhoA-regulated gene transcription in drug-resistant melanoma. Cancer Res 2018. [DOI: 10.1158/1538-7445.am2018-5895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Much of the recent focus of melanoma targeted therapy has been on the ERK pathway, which is aberrantly activated in approximately 90% of melanoma tumors. Over half of these express BRAFV600E. Current targeted therapies such as Vemurafenib (BRAFV600E inhibitor), or a combination therapy of BRAF + MEK inhibitors show profound initial effects in a majority of BRAFV600E expressing tumors. However, these responses are often short-lived and resistance typically develops within months. The goal of this work is to identify pharmacologically targetable resistance mechanisms so that effective combination therapies can be developed.
Preliminary bioinformatics analysis suggests that the RhoA subfamily of Rho GTPases is activated in BRAFi-resistant cancer cell lines and BRAFi/MEKi-resistant human melanoma tumors. Thus, we hypothesize that RhoA promotes BRAFi resistance, so simultaneously targeting RhoA and BRAF may reverse drug resistance. Using cell line models of acquired BRAFi-resistance we demonstrated that the RhoA pathway is activated in a subset of resistant cell lines. The cell lines with increased RhoA activation have increased sensitivity to multiple ROCK inhibitors.
In addition to regulating the cytoskeleton, RhoA can also regulate gene transcription through activation of multiple transcriptional co-activators, including MRTF and YAP. MRTF and YAP regulated gene transcription through their role as transcriptional co-activators and their interaction with chromatin remodeling complexes. MRTF and YAP are both activated in BRAFi-resistant cell lines. Indirectly targeting MRTF with CCG-222740 or YAP with the YES1 inhibitor Dasatinib effectively kills BRAFi-resistant melanoma cells.
Sox10 was previously identified as a gene which promotes BRAFi resistance. Expression of Sox10 is downregulated, and Sox9 is upregulated, 100-1000-fold exclusively in the resistant cell lines which have RhoA activation. Further, a Sox10 gene signature is inversely correlated with a RhoA/C signature in the TCGA dataset and melanoma scRNA-seq data. Sox10 loss is a major drug resistance melanoma in melanoma. These data suggest that targeting RhoA-regulated gene transcription may be an effective mechanism to target Sox9High/Sox10Low cells, and ultimately prevent or reverse drug resistance.
Taken together these data suggest that MRTF and YAP promote Vemurafenib resistance in Sox9High/Sox10Low melanoma cells.
Citation Format: Sean A. Misek, Kathleen A. Gallo, Richard R. Neubig. Targeting RhoA-regulated gene transcription in drug-resistant melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5895.
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Feng H, Khalil S, Neubig RR, Sidiropoulos C. A mechanistic review on GNAO1-associated movement disorder. Neurobiol Dis 2018; 116:131-141. [PMID: 29758257 DOI: 10.1016/j.nbd.2018.05.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 04/28/2018] [Accepted: 05/10/2018] [Indexed: 02/07/2023] Open
Abstract
Mutations in the GNAO1 gene cause a complex constellation of neurological disorders including epilepsy, developmental delay, and movement disorders. GNAO1 encodes Gαo, the α subunit of Go, a member of the Gi/o family of heterotrimeric G protein signal transducers. Go is the most abundant membrane protein in the mammalian central nervous system and plays major roles in synaptic neurotransmission and neurodevelopment. GNAO1 mutations were first reported in early infantile epileptic encephalopathy 17 (EIEE17) but are also associated with a more common syndrome termed neurodevelopmental disorder with involuntary movements (NEDIM). Here we review a mechanistic model in which loss-of-function (LOF) GNAO1 alleles cause epilepsy and gain-of-function (GOF) alleles are primarily associated with movement disorders. We also develop a signaling framework related to cyclic AMP (cAMP), synaptic vesicle release, and neural development and discuss gene mutations perturbing those mechanisms in a range of genetic movement disorders. Finally, we analyze clinical reports of patients carrying GNAO1 mutations with respect to their symptom onset and discuss pharmacological/surgical treatments in the context of our mechanistic model.
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Affiliation(s)
- Huijie Feng
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Suad Khalil
- Department of Neurology & Ophthalmology, Michigan State University, East Lansing, MI 48824, USA
| | - Richard R Neubig
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI 48824, USA.
| | - Christos Sidiropoulos
- Department of Neurology & Ophthalmology, Michigan State University, East Lansing, MI 48824, USA.
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Shaw VS, Mohammadiarani H, Vashisth H, Neubig RR. Differential Protein Dynamics of Regulators of G-Protein Signaling: Role in Specificity of Small-Molecule Inhibitors. J Am Chem Soc 2018; 140:3454-3460. [PMID: 29460621 DOI: 10.1021/jacs.7b13778] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Small-molecule inhibitor selectivity may be influenced by variation in dynamics among members of a protein family. Regulator of G-protein Signaling (RGS) proteins are a family that plays a key role in G-Protein Coupled Receptor (GPCR) signaling by binding to active Gα subunits and accelerating GTP hydrolysis, thereby terminating activity. Thiadiazolidinones (TDZDs) inhibit the RGS-Gα interaction by covalent modification of cysteine residues in RGS proteins. Some differences in specificity may be explained by differences in the complement of cysteines among RGS proteins. However, key cysteines shared by RGS proteins inhibited by TDZDs are not exposed on the protein surface, and differences in potency exist among RGS proteins containing only buried cysteines. We hypothesize that differential exposure of buried cysteine residues among RGS proteins partially drives TDZD selectivity. Hydrogen-deuterium exchange (HDX) studies and molecular dynamics (MD) simulations were used to probe the dynamics of RGS4, RGS8, and RGS19, three RGS proteins inhibited at a range of potencies by TDZDs. When these proteins were mutated to contain a single, shared cysteine, RGS19 was found to be most potently inhibited. HDX studies revealed differences in α4 and α6 helix flexibility among RGS isoforms, with particularly high flexibility in RGS19. This could cause differences in cysteine exposure and lead to differences in potency of TDZD inhibition. MD simulations of RGS proteins revealed motions that correspond to solvent exposure observed in HDX, providing further evidence for a role of protein dynamics in TDZD selectivity.
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Affiliation(s)
- Vincent S Shaw
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48825 , United States
| | - Hossein Mohammadiarani
- Department of Chemical Engineering , University of New Hampshire , Durham , New Hampshire 03824 , United States
| | - Harish Vashisth
- Department of Chemical Engineering , University of New Hampshire , Durham , New Hampshire 03824 , United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology , Michigan State University , East Lansing , Michigan 48825 , United States
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38
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Dripps IJ, Boyer BT, Neubig RR, Rice KC, Traynor JR, Jutkiewicz EM. Role of signalling molecules in behaviours mediated by the δ opioid receptor agonist SNC80. Br J Pharmacol 2018; 175:891-901. [PMID: 29278419 DOI: 10.1111/bph.14131] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/08/2017] [Accepted: 11/30/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND AND PURPOSE GPCRs exist in multiple conformations that can engage distinct signalling mechanisms which in turn may lead to diverse behavioural outputs. In rodent models, activation of the δ opioid receptor (δ-receptor) has been shown to elicit antihyperalgesia, antidepressant-like effects and convulsions. We recently showed that these δ-receptor-mediated behaviours are differentially regulated by the GTPase-activating protein regulator of G protein signalling 4 (RGS4), which facilitates termination of G protein signalling. To further evaluate the signalling mechanisms underlying δ-receptor-mediated antihyperalgesia, antidepressant-like effects and convulsions, we observed how changes in Gαo or arrestin proteins in vivo affected behaviours elicited by the δ-receptor agonist SNC80 in mice. EXPERIMENTAL APPROACH Transgenic mice with altered expression of various signalling molecules were used in the current studies. Antihyperalgesia was measured in a nitroglycerin-induced thermal hyperalgesia assay. Antidepressant-like effects were evaluated in the forced swim test. Mice were also observed for convulsive activity following SNC80 treatment. KEY RESULTS In Gαo RGS-insensitive heterozygous knock-in mice, the potency of SNC80 to produce antihyperalgesia and antidepressant-like effects was enhanced with no change in SNC80-induced convulsions. Conversely, in Gαo heterozygous knockout mice, SNC80-induced antihyperalgesia was abolished while antidepressant-like effects and convulsions were unaltered. No changes in SNC80-induced behaviours were observed in arrestin 3 knockout mice. SNC80-induced convulsions were potentiated in arrestin 2 knockout mice. CONCLUSIONS AND IMPLICATIONS Taken together, these findings suggest that different signalling molecules may underlie the convulsive effects of the δ-receptor relative to its antihyperalgesic and antidepressant-like effects.
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Affiliation(s)
- Isaac J Dripps
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Brett T Boyer
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Kenner C Rice
- Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, North Bethesda, MD, USA
| | - John R Traynor
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Emily M Jutkiewicz
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
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Phan HTN, Sjögren B, Neubig RR. Human Missense Mutations in Regulator of G Protein Signaling 2 Affect the Protein Function Through Multiple Mechanisms. Mol Pharmacol 2017; 92:451-458. [PMID: 28784619 DOI: 10.1124/mol.117.109215] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 08/02/2017] [Indexed: 01/11/2023] Open
Abstract
Regulator of G protein signaling 2 (RGS2) plays a significant role in alleviating vascular contraction and promoting vascular relaxation due to its GTPase accelerating protein activity toward Gαq. Mice lacking RGS2 display a hypertensive phenotype, and several RGS2 missense mutations have been found predominantly in hypertensive human subjects. However, the mechanisms whereby these mutations could impact blood pressure is unknown. Here, we selected 16 rare, missense mutations in RGS2 identified in various human exome sequencing projects and evaluated their ability to inhibit intracellular calcium release mediated by angiotensin II receptor type 1 (AT1R). Four of them had reduced function and were further investigated to elucidate underlying mechanisms. Low protein expression, protein mislocalization, and reduced G protein binding were identified as likely mechanisms of the malfunctioning mutants. The Q2L mutant had 50% lower RGS2 than wild-type (WT) protein detected by Western blot. Confocal microscopy demonstrated that R44H and D40Y had impaired plasma membrane targeting; only 46% and 35% of those proteins translocated to the plasma membrane when coexpressed with Gαq Q209L compared with 67% for WT RGS2. The R188H mutant had a significant reduction in Gαq binding affinity (10-fold increase in Ki compared with WT RGS2 in a flow cytometry competition binding assay). This study provides functional data for 16 human RGS2 missense variants on their effects on AT1R-mediated calcium mobilization and provides molecular understanding of those variants with functional loss in vitro. These molecular behaviors can provide insight to inform antihypertensive therapeutics in individuals with variants having reduced function.
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Affiliation(s)
- Hoa T N Phan
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Benita Sjögren
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
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Feng H, Sjögren B, Karaj B, Shaw V, Gezer A, Neubig RR. Movement disorder in GNAO1 encephalopathy associated with gain-of-function mutations. Neurology 2017; 89:762-770. [PMID: 28747448 DOI: 10.1212/wnl.0000000000004262] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 04/17/2017] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To define molecular mechanisms underlying the clinical spectrum of epilepsy and movement disorder in individuals with de novo mutations in the GNAO1 gene. METHODS We identified all GNAO1 mutations reported in individuals with epilepsy (early infantile epileptiform encephalopathy 17) or movement disorders through April 2016; 15 de novo mutant alleles from 25 individuals were introduced into the Gαo subunit by site-directed mutagenesis in a mammalian expression plasmid. We assessed protein expression and function in vitro in HEK-293T cells by Western blot and determined functional Gαo-dependent cyclic adenosine monophosphate (cAMP) inhibition with a coexpressed α2A adrenergic receptor. RESULTS Of the 15 clinical GNAO1 mutations studied, 9 show reduced expression and loss of function (LOF; <90% maximal inhibition). Six other mutations show variable levels of expression but exhibit normal or even gain-of-function (GOF) behavior, as demonstrated by significantly lower EC50 values for α2A adrenergic receptor-mediated inhibition of cAMP. The GNAO1 LOF mutations are associated with epileptic encephalopathy while GOF mutants (such as G42R, G203R, and E246K) or normally functioning mutants (R209) were found in patients with movement disorders with or without seizures. CONCLUSIONS Both LOF and GOF mutations in Gαo (encoded by GNAO1) are associated with neurologic pathophysiology. There appears to be a strong predictive correlation between the in vitro biochemical phenotype and the clinical pattern of epilepsy vs movement disorder.
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Affiliation(s)
- Huijie Feng
- From the Department of Pharmacology & Toxicology, Michigan State University, East Lansing
| | - Benita Sjögren
- From the Department of Pharmacology & Toxicology, Michigan State University, East Lansing
| | - Behirda Karaj
- From the Department of Pharmacology & Toxicology, Michigan State University, East Lansing
| | - Vincent Shaw
- From the Department of Pharmacology & Toxicology, Michigan State University, East Lansing
| | - Aysegul Gezer
- From the Department of Pharmacology & Toxicology, Michigan State University, East Lansing
| | - Richard R Neubig
- From the Department of Pharmacology & Toxicology, Michigan State University, East Lansing.
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Misek SA, Larsen SD, Gallo KA, Neubig RR. Abstract 89: Targeting Rho/MRTF regulated gene transcription in drug-resistant melanoma. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Much of the recent focus of melanoma targeted therapy has been on the ERK pathway, which is aberrantly activated in approximately 90% of melanoma tumors (over half of which express BRAFV600E). Current targeted therapies such as vemurafenib (BRAFV600E inhibitor), or a combination therapy using dabrafenib (BRAFV600E inhibitor) and low dose trametinib (MEK inhibitor) shows profound initial effects in a majority of BRAFV600E expressing tumors. However, these responses are often short-lived and resistances typically develops within months. Resistance to these targeted therapies can arise from multiple mechanisms, including activation of pro-survival signaling pathways parallel to the ERK pathway. The goal of this work is to identify pharmacologically targetable resistance mechanisms so that effective combination therapies can be developed.
Despite the clear role of the RhoA subfamily of Rho GTPases (RhoA/B/C) as melanoma oncogenes, their role in drug resistance is not well understood. It is challenging to develop small molecule inhibitors which directly target the activity of small Rho GTPases, so an alternative approach is to inhibit downstream pathways. Through modulation of the actin cytoskeleton Rho can induce gene transcription through multiple transcriptional co-activators including Myocardin-Related Transcription Factor (MRTF) and Yes-Associated Protein 1 (YAP).
My bioinformatics analysis demonstrates that MRTF-A gene expression is correlated with poor overall survival in a large cohort of cutaneous melanoma patients. Furthermore, expression of a set of 216 MRTF target genes is enriched in dabrafenib/trametinib resistant cutaneous melanoma tumors compared to matched pre-treatment tumors, suggesting that MRTF activation may be involved in drug resistance. Based upon these results I hypothesized that small Rho GTPases may promote resistance to MAPK pathway targeted therapies through activation of MRTF/YAP.
To test this hypothesis, I generated vemurafenib resistant melanoma cells through chronic exposure to vemurafenib. This vemurafenib-resistant cell population is enriched for actin stress fiber positive cells, and these cells have increased Myosin Light Chain 2 (MLC2) phosphorylation, suggesting that there is increased Rho activation. Furthermore, these drug resistant cells are more sensitive to pharmacological inhibition of MRTF activity. These preliminary data suggest that vemurafenib resistant melanoma cells may be re-wired to depend on the Rho-induced gene transcription for their survival, and that a combination therapy simultaneously targeting these two pathways may be an effective treatment strategy for BRAF inhibitor-resistant melanomas.
Citation Format: Sean A. Misek, Scott D. Larsen, Kathleen A. Gallo, Richard R. Neubig. Targeting Rho/MRTF regulated gene transcription in drug-resistant melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 89. doi:10.1158/1538-7445.AM2017-89
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Johnson LA, Rodansky ES, Moons DS, Larsen SD, Neubig RR, Higgins PDR. Optimisation of Intestinal Fibrosis and Survival in the Mouse S. Typhimurium Model for Anti-fibrotic Drug Discovery and Preclinical Applications. J Crohns Colitis 2017; 11:724-736. [PMID: 27986839 PMCID: PMC5881735 DOI: 10.1093/ecco-jcc/jjw210] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 10/19/2016] [Accepted: 11/17/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND AIMS Intestinal fibrosis is a frequent complication in Crohn's disease [CD]. The mouse Salmonella typhimurium model, due to its simplicity, reproducibility, manipulability, and penetrance, is an established fibrosis model for drug discovery and preclinical trials. However, the severity of fibrosis and mortality are host- and bacterial strain-dependent, thus limiting the original model. We re-evaluated the S. typhimurium model to optimise fibrosis and survival, using commercially available mouse strains. METHODS Fibrotic and inflammatory markers were evaluated across S. typhimurium ΔaroA:C57bl/6 studies performed in our laboratory. A model optimisation study was performed using three commercially available mouse strains [CBA/J, DBA/J, and 129S1/SvImJ] infected with either SL1344 or ΔaroA S. typhimurium. Fibrotic penetrance was determined by histopathology, gene expression, and αSMA protein expression. Fibrosis severity, penetrance, and survival were analysed across subsequent CBA studies. RESULTS Fibrosis severity and survival are both host- and bacterial strain-dependent. Marked tissue fibrosis and 100% survival occurred in the CBA/J strain infected with SL1344. Subsequent experiments demonstrated that CBA/J mice develop extensive intestinal fibrosis, characterised by transmural tissue fibrosis, a Th1/Th17 cytokine response, and induction of pro-fibrotic genes and extracellular matrix proteins. A meta-analysis of subsequent SL1344:CBA/J studies demonstrated that intestinal fibrosis is consistent and highly penetrant across histological, protein, and gene expression markers. As proof-of-concept, we tested the utility of the SL1344:CBA/J fibrosis model to evaluate efficacy of CCG-203971, a novel anti-fibrotic drug. CONCLUSION The S. typhimurium SL1344:CBA/J model is an optimised model for the study of intestinal fibrosis.
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Affiliation(s)
- Laura A Johnson
- Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - Eva S Rodansky
- Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - David S Moons
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Scott D Larsen
- Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI, USA
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, Lansing, MI, USA
| | - Peter D R Higgins
- Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
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Shaw VS, Schilmiller AL, Vashisth H, Neubig RR. Investigating Regulator of G‐protein Signaling (RGS) Protein Dynamics by Hydrogen/Deuterium Exchange. FASEB J 2017. [DOI: 10.1096/fasebj.31.1_supplement.665.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Vincent S. Shaw
- Pharmacology and ToxicologyMichigan State UniversityEast LansingMI
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Yu-Wai-Man C, Spencer-Dene B, Lee RMH, Hutchings K, Lisabeth EM, Treisman R, Bailly M, Larsen SD, Neubig RR, Khaw PT. Local delivery of novel MRTF/SRF inhibitors prevents scar tissue formation in a preclinical model of fibrosis. Sci Rep 2017; 7:518. [PMID: 28364121 PMCID: PMC5428058 DOI: 10.1038/s41598-017-00212-w] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 02/14/2017] [Indexed: 11/09/2022] Open
Abstract
The myocardin-related transcription factor/serum response factor (MRTF/SRF) pathway represents a promising therapeutic target to prevent fibrosis. We have tested the effects of new pharmacological inhibitors of MRTF/SRF signalling in a preclinical model of fibrosis. CCG-222740, a novel MRTF/SRF inhibitor, markedly decreased SRF reporter gene activity and showed a greater inhibitory effect on MRTF/SRF target genes than the previously described MRTF-A inhibitor CCG-203971. CCG-222740 was also five times more potent, with an IC50 of 5 μM, in a fibroblast-mediated collagen contraction assay, was less cytotoxic, and a more potent inhibitor of alpha-smooth muscle actin protein expression than CCG-203971. Local delivery of CCG-222740 and CCG-203971 in a validated and clinically relevant rabbit model of scar tissue formation after glaucoma filtration surgery increased the long-term success of the surgery by 67% (P < 0.0005) and 33% (P < 0.01), respectively, and significantly decreased fibrosis and scarring histologically. Unlike mitomycin-C, neither CCG-222740 nor CCG-203971 caused any detectable epithelial toxicity or systemic side effects with very low drug levels measured in the aqueous, vitreous, and serum. We conclude that inhibitors of MRTF/SRF-regulated gene transcription such as CCG-222740, potentially represent a new therapeutic strategy to prevent scar tissue formation in the eye and other tissues.
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Affiliation(s)
- Cynthia Yu-Wai-Man
- UCL Institute of Ophthalmology, London, UK. .,National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK. .,Signalling and Transcription Group, Francis Crick Institute, London, UK.
| | | | - Richard M H Lee
- National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - Kim Hutchings
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Erika M Lisabeth
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Richard Treisman
- Signalling and Transcription Group, Francis Crick Institute, London, UK
| | | | - Scott D Larsen
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Peng T Khaw
- National Institute for Health Research (NIHR) Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
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45
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Rovati GE, Capra V, Shaw VS, Malik RU, Sivaramakrishnan S, Neubig RR. The DRY motif and the four corners of the cubic ternary complex model. Cell Signal 2017; 35:16-23. [PMID: 28347873 DOI: 10.1016/j.cellsig.2017.03.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 03/24/2017] [Indexed: 12/14/2022]
Abstract
Recent structural data on GPCRs using a variety of spectroscopic approaches suggest that GPCRs adopt a dynamic conformational landscape, with ligands stabilizing subsets of these states to activate one or more downstream signaling effectors. A key outstanding question posed by this emerging dynamic structural model of GPCRs is what states, active, inactive, or intermediate are captured by the numerous crystal structures of GPCRs complexed with a variety of agonists, partial agonists, and antagonists. In the early nineties the discovery of inverse agonists and constitutive activity led to the idea that the active receptor state (R⁎) is an intrinsic property of the receptor itself rather than of the RG complex, eventually leading to the formulation of the cubic ternary complex model (CTC). Here, by a careful analysis of a series of data obtained with a number of mutants of the highly conserved E/DRY motif, we show evidences for the existence of all the receptor states theorized by the CTC, four 'uncoupled (R, R⁎ and HR and HR⁎), and, consequently four 'coupled' (RG, R⁎G, HRG and HR⁎G). The E/DRY motif located at the cytosolic end of transmembrane helix III of Class A GPCRs has been widely studied and analyzed because it forms a network of interactions believed to lock receptors in the inactive conformation (R), and, thus, to play a key role in receptor activation. Our conclusions are supported by recent crystal and NMR spectra, as well as by results obtained with two prototypical GPCRs using a new FRET technology that de-couples G protein binding to the receptor from signal transduction. Thus, despite its complexity and limitations, we propose that the CTC is a useful framework to reconcile pharmacological, biochemical and structural data.
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Affiliation(s)
- G Enrico Rovati
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milano, Italy.
| | - Valérie Capra
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milano, Italy; Department of Health Science, University of Milan, Milano, Italy.
| | - Vincent S Shaw
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, USA.
| | - Rabia U Malik
- Department of Genetics, Cell Biology & Development, College of Biological Sciences, University of Minnesota Twin Cities, Minneapolis, MN, USA.
| | - Sivaraj Sivaramakrishnan
- Department of Genetics, Cell Biology & Development, College of Biological Sciences, University of Minnesota Twin Cities, Minneapolis, MN, USA.
| | - Richard R Neubig
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, USA.
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46
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Hutchings KM, Lisabeth EM, Rajeswaran W, Wilson MW, Sorenson RJ, Campbell PL, Ruth JH, Amin A, Tsou PS, Leipprandt JR, Olson SR, Wen B, Zhao T, Sun D, Khanna D, Fox DA, Neubig RR, Larsen SD. Pharmacokinetic optimitzation of CCG-203971: Novel inhibitors of the Rho/MRTF/SRF transcriptional pathway as potential antifibrotic therapeutics for systemic scleroderma. Bioorg Med Chem Lett 2017; 27:1744-1749. [PMID: 28285914 DOI: 10.1016/j.bmcl.2017.02.070] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 02/24/2017] [Accepted: 02/26/2017] [Indexed: 11/30/2022]
Abstract
We recently reported the development of a novel inhibitor of Rho-mediated gene transcription (1, CCG-203971) that is efficacious in multiple animal models of acute fibrosis, including scleroderma, when given intraperitoneally. The modest in vivo potency and poor pharmacokinetics (PK) of this lead, however, make it unsuitable for long term efficacy studies. We therefore undertook a systematic medicinal chemistry effort to improve both the metabolic stability and the solubility of 1, resulting in the identification of two analogs achieving over 10-fold increases in plasma exposures in mice. We subsequently showed that one of these analogs (8f, CCG-232601) could inhibit the development of bleomycin-induced dermal fibrosis in mice when administered orally at 50mg/kg, an effect that was comparable to what we had observed earlier with 1 at a 4-fold higher IP dose.
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Affiliation(s)
- Kim M Hutchings
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Erika M Lisabeth
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Walajapet Rajeswaran
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael W Wilson
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Roderick J Sorenson
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Phillip L Campbell
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - Jeffrey H Ruth
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - Asif Amin
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - Pei-Suen Tsou
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - Jeffrey R Leipprandt
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Samuel R Olson
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Bo Wen
- UM Pharmacokinetics Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ting Zhao
- UM Pharmacokinetics Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Duxin Sun
- UM Pharmacokinetics Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Dinesh Khanna
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - David A Fox
- Department of Internal Medicine, Division of Rheumatology and Clinical Autoimmunity Center of Excellence, University of Michigan Medical Center, Ann Arbor, MI 48109, USA
| | - Richard R Neubig
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Scott D Larsen
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA.
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Dripps IJ, Wang Q, Neubig RR, Rice KC, Traynor JR, Jutkiewicz EM. The role of regulator of G protein signaling 4 in delta-opioid receptor-mediated behaviors. Psychopharmacology (Berl) 2017; 234:29-39. [PMID: 27624599 PMCID: PMC5203942 DOI: 10.1007/s00213-016-4432-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 09/04/2016] [Indexed: 01/08/2023]
Abstract
RATIONALE Regulator of G protein signaling (RGS) proteins act as negative modulators of G protein signaling. RGS4 has been shown to negatively modulate G protein signaling mediated by the delta opioid receptor (DOPr) in vitro. However, the role of RGS4 in modulating DOPr-mediated behaviors in vivo has not been elucidated. OBJECTIVE The aim of this study was to compare the ability of the DOPr agonist SNC80 to induce DOPr-mediated antinociception, antihyperalgesia, antidepressant-like effects, and convulsions in wild-type and RGS4 knockout mice. METHODS Antinociception was assessed in the acetic acid stretch assay. Antihyperalgesia was measured in a nitroglycerin-induced thermal hyperalgesia assay. Antidepressant-like effects were evaluated in the forced swim and tail suspension tests. Mice were also observed for convulsive activity post-SNC80 treatment. SNC80-induced phosphorylation of MAP kinase in striatal tissue from RGS4 wild-type and knockout mice was quantified by Western blot. DOPr number from forebrain tissue was measured using [3H]DPDPE saturation binding. RESULTS Elimination of RGS4 potentiated SNC80-induced antinociception and antihyperalgesia. SNC80-induced antidepressant-like effects were potentiated in RGS4 knockout mice in the forced swim test but not in the tail suspension test. Additionally, RGS4 knockout did not alter SNC80-induced convulsions. SNC80-induced phosphorylation of MAP kinase was potentiated in striatum from RGS4 knockout mice. Loss of RGS4 did not affect total DOPr number. CONCLUSIONS Overall, these findings demonstrate that reduction of RGS4 functionally may increase the therapeutic index of SNC80. These results provide the first evidence of differential regulation of DOPr-mediated behaviors by RGS proteins and G protein signaling pathways.
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Affiliation(s)
- Isaac J. Dripps
- Department of Pharmacology, University of Michigan Medical School
| | - Qin Wang
- Department of Pharmacology, University of Michigan Medical School
| | - Richard R. Neubig
- Department of Pharmacology and Toxicology, Michigan State University
| | - Kenner C. Rice
- Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse
| | - John R Traynor
- Department of Pharmacology, University of Michigan Medical School
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Rorabaugh BR, Chakravarti B, Mabe NW, Seeley SL, Bui AD, Yang J, Watts SW, Neubig RR, Fisher RA. Regulator of G Protein Signaling 6 Protects the Heart from Ischemic Injury. J Pharmacol Exp Ther 2016; 360:409-416. [PMID: 28035008 DOI: 10.1124/jpet.116.238345] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 12/28/2016] [Indexed: 01/07/2023] Open
Abstract
Gαi-coupled receptors play important roles in protecting the heart from ischemic injury. Regulator of G protein signaling (RGS) proteins suppress Gαi signaling by accelerating the GTPase activity of Gαi subunits. However, the roles of individual RGS proteins in modulating ischemic injury are unknown. In this study, we investigated the effect of RGS6 deletion on myocardial sensitivity to ischemic injury. Hearts from RGS6 knockout (RGS6-/-) and RGS6 wild-type (RGS6+/+) mice were subjected to 30 minutes of ischemia and 2 hours of reperfusion on a Langendorff heart apparatus. Infarcts in RGS6-/- hearts were significantly larger than infarcts in RGS6+/+ hearts. RGS6-/- hearts also exhibited increased phosphorylation of β2-adrenergic receptors and G protein-coupled receptor kinase 2 (GRK2). Mitochondrial GRK2 as well as caspase-3 cleavage were increased significantly in RGS6-/- hearts compared with RGS6+/+ hearts after ischemia. Chronic propranolol treatment of mice prevented the observed increases in ischemic injury and the GRK2 phosphorylation observed in RGS6-/- hearts. Our findings suggest that loss of RGS6 predisposes the ventricle to prodeath signaling through a β2AR-GRK2-dependent signaling mechanism, and they provide evidence for a protective role of RGS6 in the ischemic heart. Individuals expressing genetic polymorphisms that suppress the activity of RGS6 may be at increased risk of cardiac ischemic injury. Furthermore, the development of agents that increase RGS6 expression or activity might provide a novel strategy for the treatment of ischemic heart disease.
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Affiliation(s)
- Boyd R Rorabaugh
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Bandana Chakravarti
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Nathaniel W Mabe
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Sarah L Seeley
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Albert D Bui
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Jianqi Yang
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Stephanie W Watts
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Richard R Neubig
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
| | - Rory A Fisher
- Department of Pharmaceutical and Biomedical Sciences, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio (B.R.R., N.W.M., S.L.S., A.D.B.); Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa (B.C., J.Y., R.A.F.); and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (S.W.W., R.R.N.)
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49
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Ferland DJ, Darios ES, Neubig RR, Sjögren B, Truong N, Torres R, Dexheimer TS, Thompson JM, Watts SW. Chemerin-induced arterial contraction is G i- and calcium-dependent. Vascul Pharmacol 2016; 88:30-41. [PMID: 27890480 DOI: 10.1016/j.vph.2016.11.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 10/27/2016] [Accepted: 11/21/2016] [Indexed: 12/12/2022]
Abstract
Chemerin is an adipokine associated with increased blood pressure, and may link obesity with hypertension. We tested the hypothesis that chemerin-induced contraction of the vasculature occurs via calcium flux in smooth muscle cells. Isometric contraction of rat aortic rings was performed in parallel with calcium kinetics of rat aortic smooth muscle cells to assess the possible signaling pathway. Chemerin-9 (nonapeptide of the chemerin S157 isoform) caused a concentration-dependent contraction of isolated aorta (EC50 100nM) and elicited a concentration-dependent intracellular calcium response (EC50 10nM). Pertussis toxin (Gi inhibitor), verapamil (L-type Ca2+ channel inhibitor), PP1 (Src inhibitor), and Y27632 (Rho kinase inhibitor) reduced both calcium influx and isometric contraction to chemerin-9 but PD098059 (Erk MAPK inhibitor) and U73122 (PLC inhibitor) had little to no effect on either measure of chemerin signaling. Although our primary aim was to examine chemerin signaling, we also highlight differences in the mechanisms of chemerin-9 and recombinant chemerin S157. These data support a chemerin-induced contractile mechanism in vascular smooth muscle that functions through Gi proteins to activate L-type Ca2+ channels, Src, and Rho kinase. There is mounting evidence linking chemerin to hypertension and this mechanism brings us closer to targeting chemerin as a form of therapy.
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MESH Headings
- Animals
- Aorta/drug effects
- Aorta/metabolism
- Calcium/metabolism
- Calcium Channels, L-Type/metabolism
- Chemokines/administration & dosage
- Chemokines/metabolism
- Dose-Response Relationship, Drug
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- Hypertension/physiopathology
- Intercellular Signaling Peptides and Proteins/administration & dosage
- Intercellular Signaling Peptides and Proteins/metabolism
- Male
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/drug effects
- rho-Associated Kinases/metabolism
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Affiliation(s)
- David J Ferland
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States.
| | - Emma S Darios
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Richard R Neubig
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Benita Sjögren
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Nguyen Truong
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Rosa Torres
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Thomas S Dexheimer
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Janice M Thompson
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
| | - Stephanie W Watts
- Department of Pharmacology and Toxicology, 1355 Bogue Street Rm B445, Michigan State University, East Lansing, MI 48824-1317, United States
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50
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Haak AJ, Appleton KM, Lisabeth EM, Misek SA, Ji Y, Wade SM, Bell JL, Rockwell CE, Airik M, Krook MA, Larsen SD, Verhaegen M, Lawlor ER, Neubig RR. Pharmacological Inhibition of Myocardin-related Transcription Factor Pathway Blocks Lung Metastases of RhoC-Overexpressing Melanoma. Mol Cancer Ther 2016; 16:193-204. [PMID: 27837031 DOI: 10.1158/1535-7163.mct-16-0482] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/17/2016] [Accepted: 10/21/2016] [Indexed: 02/04/2023]
Abstract
Melanoma is the most dangerous form of skin cancer with the majority of deaths arising from metastatic disease. Evidence implicates Rho-activated gene transcription in melanoma metastasis mediated by the nuclear localization of the transcriptional coactivator, myocardin-related transcription factor (MRTF). Here, we highlight a role for Rho and MRTF signaling and its reversal by pharmacologic inhibition using in vitro and in vivo models of human melanoma growth and metastasis. Using two cellular models of melanoma, we clearly show that one cell type, SK-Mel-147, is highly metastatic, has high RhoC expression, and MRTF nuclear localization and activity. Conversely, SK-Mel-19 melanoma cells have low RhoC expression, and decreased levels of MRTF-regulated genes. To probe the dependence of melanoma aggressiveness to MRTF transcription, we use a previously developed small-molecule inhibitor, CCG-203971, which at low micromolar concentrations blocks nuclear localization and activity of MRTF-A. In SK-Mel-147 cells, CCG-203971 inhibits cellular migration and invasion, and decreases MRTF target gene expression. In addition, CCG-203971-mediated inhibition of the Rho/MRTF pathway significantly reduces cell growth and clonogenicity and causes G1 cell-cycle arrest. In an experimental model of melanoma lung metastasis, the RhoC-overexpressing melanoma cells (SK-Mel-147) exhibited pronounced lung colonization compared with the low RhoC-expressing SK-Mel-19. Furthermore, pharmacologic inhibition of the MRTF pathway reduced both the number and size of lung metastasis resulting in a marked reduction of total lung tumor burden. These data link Rho and MRTF-mediated signaling with aggressive phenotypes and support targeting the MRTF transcriptional pathway as a novel approach to melanoma therapeutics. Mol Cancer Ther; 16(1); 193-204. ©2016 AACR.
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Affiliation(s)
- Andrew J Haak
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Kathryn M Appleton
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, Michigan
| | - Erika M Lisabeth
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, Michigan
| | - Sean A Misek
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, Michigan
| | - Yajing Ji
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, Michigan
| | - Susan M Wade
- Department of Pharmacology, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Jessica L Bell
- Department of Medicinal Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan.,College of Pharmacy, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Cheryl E Rockwell
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, Michigan
| | - Merlin Airik
- Department of Pediatrics, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Melanie A Krook
- Department of Pediatrics, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Scott D Larsen
- Department of Medicinal Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan.,College of Pharmacy, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Monique Verhaegen
- Department of Dermatology, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Elizabeth R Lawlor
- Department of Pediatrics, University of Michigan Medical Center, Ann Arbor, Michigan
| | - Richard R Neubig
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, Michigan.
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