1
|
Yuan W, Shi X, Lee LTO. RNA therapeutics in targeting G protein-coupled receptors: Recent advances and challenges. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102195. [PMID: 38741614 PMCID: PMC11089380 DOI: 10.1016/j.omtn.2024.102195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
G protein-coupled receptors (GPCRs) are the major targets of existing drugs for a plethora of human diseases and dominate the pharmaceutical market. However, over 50% of the GPCRs remain undruggable. To pursue a breakthrough and overcome this situation, there is significant clinical research for developing RNA-based drugs specifically targeting GPCRs, but none has been approved so far. RNA therapeutics represent a unique and promising approach to selectively targeting previously undruggable targets, including undruggable GPCRs. However, the development of RNA therapeutics faces significant challenges in areas of RNA stability and efficient in vivo delivery. This review presents an overview of the advances in RNA therapeutics and the diverse types of nanoparticle RNA delivery systems. It also describes the potential applications of GPCR-targeted RNA drugs for various human diseases.
Collapse
Affiliation(s)
- Wanjun Yuan
- Cancer Centre, Faculty of Health Sciences, University of Macau, Taipa 999078, Macau, China
| | - Xiangyang Shi
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, People’s Republic of China
| | - Leo Tsz On Lee
- Cancer Centre, Faculty of Health Sciences, University of Macau, Taipa 999078, Macau, China
- Ministry of Education Frontiers Science Center for Precision Oncology, University of Macau, Taipa 999078, Macau, China
| |
Collapse
|
2
|
Gui J, Zhou H, Wan H, Yang D, Liu Q, Zhu L, Mi Y. The Role of Vasodilator-stimulated Phosphoproteins in the Development of Malignant Tumors. Curr Cancer Drug Targets 2024; 24:477-489. [PMID: 37962042 PMCID: PMC11092557 DOI: 10.2174/0115680096262439231023110106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/06/2023] [Accepted: 09/06/2023] [Indexed: 11/15/2023]
Abstract
Vasodilator-stimulated phosphoprotein (VASP) is an actin-binding protein that includes three structural domains: Enabled/VASP homolog1 (EVH1), EVH2, and proline-rich (PRR). VASP plays an important role in various cellular behaviors related to cytoskeletal regulation. More importantly, VASP plays a key role in the progression of several malignant tumors and is associated with malignant cell proliferation, invasion, and metastasis. Here, we have summarized current studies on the impact of VASP on the development of several malignant tumors and their mechanisms. This study provides a new theoretical basis for clinical molecular diagnosis and molecular targeted therapy.
Collapse
Affiliation(s)
- Jiandong Gui
- Wuxi School of Medicine, Jiangnan University, 1800 Lihudadao, Wuxi, 214122, Jiangsu Province, China
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
| | - Hangsheng Zhou
- Wuxi School of Medicine, Jiangnan University, 1800 Lihudadao, Wuxi, 214122, Jiangsu Province, China
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
| | - Hongyuan Wan
- Wuxi School of Medicine, Jiangnan University, 1800 Lihudadao, Wuxi, 214122, Jiangsu Province, China
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
| | - Dongjie Yang
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
| | - Qing Liu
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
- Huadong Sanatorium, 67 Dajishan, Wuxi 214122, Jiangsu Province, China
| | - Lijie Zhu
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
| | - Yuanyuan Mi
- Department of Urology, Affiliated Hospital of Jiangnan University, 1000 Hefeng Road, Wuxi, 214122, Jiangsu Province, China
| |
Collapse
|
3
|
Nayak AP, Javed E, Villalba DR, Wang Y, Morelli HP, Shah SD, Kim N, Ostrom RS, Panettieri RA, An SS, Tang DD, Penn RB. Prorelaxant E-type Prostanoid Receptors Functionally Partition to Different Procontractile Receptors in Airway Smooth Muscle. Am J Respir Cell Mol Biol 2023; 69:584-591. [PMID: 37523713 PMCID: PMC10633839 DOI: 10.1165/rcmb.2022-0445oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 07/31/2023] [Indexed: 08/02/2023] Open
Abstract
Prostaglandin E2 imparts diverse physiological effects on multiple airway cells through its actions on four distinct E-type prostanoid (EP) receptor subtypes (EP1-EP4). Gs-coupled EP2 and EP4 receptors are expressed on airway smooth muscle (ASM), yet their capacity to regulate the ASM contractile state remains subject to debate. We used EP2 and EP4 subtype-specific agonists (ONO-259 and ONO-329, respectively) in cell- and tissue-based models of human ASM contraction-magnetic twisting cytometry (MTC), and precision-cut lung slices (PCLSs), respectively-to study the EP2 and EP4 regulation of ASM contraction and signaling under conditions of histamine or methacholine (MCh) stimulation. ONO-329 was superior (<0.05) to ONO-259 in relaxing MCh-contracted PCLSs (log half maximal effective concentration [logEC50]: 4.9 × 10-7 vs. 2.2 × 10-6; maximal bronchodilation ± SE, 35 ± 2% vs. 15 ± 2%). However, ONO-259 and ONO-329 were similarly efficacious in relaxing histamine-contracted PCLSs. Similar differential effects were observed in MTC studies. Signaling analyses revealed only modest differences in ONO-329- and ONO-259-induced phosphorylation of the protein kinase A substrates VASP and HSP20, with concomitant stimulation with MCh or histamine. Conversely, ONO-259 failed to inhibit MCh-induced phosphorylation of the regulatory myosin light chain (pMLC20) and the F-actin/G-actin ratio (F/G-actin ratio) while effectively inhibiting their induction by histamine. ONO-329 was effective in reversing induced pMLC20 and the F/G-actin ratio with both MCh and histamine. Thus, the contractile-agonist-dependent differential effects are not explained by changes in the global levels of phosphorylated protein kinase A substrates but are reflected in the regulation of pMLC20 (cross-bridge cycling) and F/G-actin ratio (actin cytoskeleton integrity, force transmission), implicating a role for compartmentalized signaling involving muscarinic, histamine, and EP receptor subtypes.
Collapse
Affiliation(s)
- Ajay P. Nayak
- Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Elham Javed
- Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Dominic R. Villalba
- Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Yinna Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Henry P. Morelli
- Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Sushrut D. Shah
- Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Nicholas Kim
- Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, New Jersey
| | - Rennolds S. Ostrom
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, California; and
| | - Reynold A. Panettieri
- Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, New Jersey
| | - Steven S. An
- Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, New Jersey
| | - Dale D. Tang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Raymond B. Penn
- Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| |
Collapse
|
4
|
Greenwald E, Posner C, Bharath A, Lyons A, Salmerón C, Sriram K, Wiley SZ, Insel PA, Zhang J. GPCR Signaling Measurement and Drug Profiling with an Automated Live-Cell Microscopy System. ACS Sens 2023; 8:19-27. [PMID: 36602887 PMCID: PMC9994309 DOI: 10.1021/acssensors.2c01341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A major limitation of time-lapse microscopy combined with fluorescent biosensors, a powerful tool for quantifying spatiotemporal dynamics of signaling in single living cells, is low-experimental throughput. To overcome this limitation, we created a highly customizable, MATLAB-based platform: flexible automated liquid-handling combined microscope (FALCOscope) that coordinates an OpenTrons liquid handler and a fluorescence microscope to automate drug treatments, fluorescence imaging, and single-cell analysis. To test the feasibility of the FALCOscope, we quantified G protein-coupled receptor (GPCR)-stimulated Protein Kinase A activity and cAMP responses to GPCR agonists and antagonists. We also characterized cAMP dynamics induced by GPR68/OGR1, a proton-sensing GPCR, in response to variable extracellular pH values. GPR68-induced cAMP responses were more transient in acidic than neutral pH values, suggesting a pH-dependence for signal attenuation. Ogerin, a GPR68 positive allosteric modulator, enhanced cAMP response most strongly at pH 7.0 and sustained cAMP response for acidic pH values, thereby demonstrating the capability of the FALCOscope to capture allosteric modulation. At a high concentration, ogerin increased cAMP signaling independent of GPR68, likely via phosphodiesterase inhibition. The FALCOscope system thus enables enhanced throughput single-cell dynamic measurements and is a versatile system for interrogating spatiotemporal regulation of signaling molecules in living cells and for drug profiling and screening.
Collapse
Affiliation(s)
- Eric Greenwald
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Clara Posner
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Ananya Bharath
- Department of Chemical Engineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Anne Lyons
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States
| | - Cristina Salmerón
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Krishna Sriram
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Shu Z Wiley
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States
| | - Paul A Insel
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States.,Department of Medicine, University of California, San Diego, La Jolla, California 92093 United States
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093, United States.,Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States.,Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| |
Collapse
|
5
|
In silico identification of a β 2-adrenoceptor allosteric site that selectively augments canonical β 2AR-Gs signaling and function. Proc Natl Acad Sci U S A 2022; 119:e2214024119. [PMID: 36449547 PMCID: PMC9894167 DOI: 10.1073/pnas.2214024119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Activation of β2-adrenoceptors (β2ARs) causes airway smooth muscle (ASM) relaxation and bronchodilation, and β2AR agonists (β-agonists) are front-line treatments for asthma and other obstructive lung diseases. However, the therapeutic efficacy of β-agonists is limited by agonist-induced β2AR desensitization and noncanonical β2AR signaling involving β-arrestin that is shown to promote asthma pathophysiology. Accordingly, we undertook the identification of an allosteric site on β2AR that could modulate the activity of β-agonists to overcome these limitations. We employed the site identification by ligand competitive saturation (SILCS) computational method to comprehensively map the entire 3D structure of in silico-generated β2AR intermediate conformations and identified a putative allosteric binding site. Subsequent database screening using SILCS identified drug-like molecules with the potential to bind to the site. Experimental assays in HEK293 cells (expressing recombinant wild-type human β2AR) and human ASM cells (expressing endogenous β2AR) identified positive and negative allosteric modulators (PAMs and NAMs) of β2AR as assessed by regulation of β-agonist-stimulation of cyclic AMP generation. PAMs/NAMs had no effect on β-agonist-induced recruitment of β-arrestin to β2AR- or β-agonist-induced loss of cell surface expression in HEK293 cells expressing β2AR. Mutagenesis analysis of β2AR confirmed the SILCS identified site based on mutants of amino acids R131, Y219, and F282. Finally, functional studies revealed augmentation of β-agonist-induced relaxation of contracted human ASM cells and bronchodilation of contracted airways. These findings identify a allosteric binding site on the β2AR, whose activation selectively augments β-agonist-induced Gs signaling, and increases relaxation of ASM cells, the principal therapeutic effect of β-agonists.
Collapse
|
6
|
Nayak AP, An SS. Anxiolytics for Bronchodilation: Refinements to GABA A Agonists for Asthma Relief. Am J Respir Cell Mol Biol 2022; 67:419-420. [PMID: 35901197 PMCID: PMC9564927 DOI: 10.1165/rcmb.2022-0287ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Ajay P. Nayak
- Center for Translational Medicine,Department of MedicineThomas Jefferson UniversityPhiladelphia, Pennsylvania
| | - Steven S. An
- Rutgers Institute for Translational Medicine and ScienceNew Brunswick, New Jersey,Rutgers-Robert Wood Johnson Medical SchoolThe State University of New JerseyPiscataway, New Jersey
| |
Collapse
|
7
|
Bell TJ, Nagel DJ, Woeller CF, Kottmann RM. Ogerin mediated inhibition of TGF-β(1) induced myofibroblast differentiation is potentiated by acidic pH. PLoS One 2022; 17:e0271608. [PMID: 35901086 PMCID: PMC9333254 DOI: 10.1371/journal.pone.0271608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 07/01/2022] [Indexed: 01/28/2023] Open
Abstract
Transforming growth factor beta (TGF-β) induced myofibroblast differentiation is central to the pathological scarring observed in Idiopathic Pulmonary Fibrosis (IPF) and other fibrotic diseases. Our lab has recently identified expression of GPR68 (Ovarian Cancer Gene Receptor 1, OGR1), a pH sensing G-protein coupled receptor, as a negative regulator of TGF-β induced profibrotic effects in primary human lung fibroblasts (PHLFs). We therefore hypothesized that small molecule activators of GPR68 would inhibit myofibroblast differentiation. Ogerin is a positive allosteric modulator (PAM) of GPR68, inducing a leftward shift of the dose response curve to proton induced signaling. Using PHLFs derived from patients with both non-fibrotic and IPF diagnoses, we show that Ogerin inhibits, and partially reverses TGF-β induced myofibroblast differentiation in a dose dependent manner. This occurs at the transcriptional level without inhibition of canonical TGF-β induced SMAD signaling. Ogerin induces PKA dependent CREB phosphorylation, a marker of Gαs pathway activation. The ability of Ogerin to inhibit both basal and TGF-β induced collagen gene transcription, and induction of Gαs signaling is enhanced at an acidic pH (pH 6.8). Similar findings were also found using fibroblasts derived from dermal, intestinal, and orbital tissue. The biological role of GPR68 in different tissues, cell types, and disease states is an evolving and emerging field. This work adds to the understanding of Gαs coupled GPCRs in fibrotic lung disease, the ability to harness the pH sensing properties of GPR68, and conserved mechanisms of fibrosis across different organ systems.
Collapse
Affiliation(s)
- Tyler J. Bell
- Department of Environmental Medicine Toxicology Training Program, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - David J. Nagel
- Department of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - Collynn F. Woeller
- Department of Ophthalmology, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - R. Mathew Kottmann
- Department of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
- * E-mail:
| |
Collapse
|
8
|
Imenez Silva PH, Câmara NO, Wagner CA. Role of proton-activated G protein-coupled receptors in pathophysiology. Am J Physiol Cell Physiol 2022; 323:C400-C414. [PMID: 35759438 DOI: 10.1152/ajpcell.00114.2022] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Local acidification is a common feature of many disease processes such as inflammation, infarction, or solid tumor growth. Acidic pH is not merely a sequelae of disease but contributes to recruitment and regulation of immune cells, modifies metabolism of parenchymal, immune and tumor cells, modulates fibrosis, vascular permeability, oxygen availability and consumption, invasiveness of tumor cells, and impacts on cell survival. Thus, multiple pH-sensing mechanisms must exist in cells involved in these processes. These pH-sensors play important roles in normal physiology and pathophysiology, and hence might be attractive targets for pharmacological interventions. Among the pH-sensing mechanisms, OGR1 (GPR68), GPR4 (GPR4), and TDAG8 (GPR65) have emerged as important molecules. These G protein-coupled receptors are widely expressed, are upregulated in inflammation and tumors, sense changes in extracellular pH in the range between pH 8 and 6, and are involved in modulating key processes in inflammation, tumor biology, and fibrosis. This review discusses key features of these receptors and highlights important disease states and pathways affected by their activity.
Collapse
Affiliation(s)
- Pedro H Imenez Silva
- Institute of Physiology, University of Zurich, Zurich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Switzerland
| | - Niels Olsen Câmara
- Department of Immunology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Carsten A Wagner
- Institute of Physiology, University of Zurich, Zurich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Switzerland
| |
Collapse
|
9
|
Imenez Silva PH, Wagner CA. Physiological relevance of proton-activated GPCRs. Pflugers Arch 2022; 474:487-504. [PMID: 35247105 PMCID: PMC8993716 DOI: 10.1007/s00424-022-02671-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 12/12/2022]
Abstract
The detection of H+ concentration variations in the extracellular milieu is accomplished by a series of specialized and non-specialized pH-sensing mechanisms. The proton-activated G protein–coupled receptors (GPCRs) GPR4 (Gpr4), TDAG8 (Gpr65), and OGR1 (Gpr68) form a subfamily of proteins capable of triggering intracellular signaling in response to alterations in extracellular pH around physiological values, i.e., in the range between pH 7.5 and 6.5. Expression of these receptors is widespread for GPR4 and OGR1 with particularly high levels in endothelial cells and vascular smooth muscle cells, respectively, while expression of TDAG8 appears to be more restricted to the immune compartment. These receptors have been linked to several well-studied pH-dependent physiological activities including central control of respiration, renal adaption to changes in acid–base status, secretion of insulin and peripheral responsiveness to insulin, mechanosensation, and cellular chemotaxis. Their role in pathological processes such as the genesis and progression of several inflammatory diseases (asthma, inflammatory bowel disease), and tumor cell metabolism and invasiveness, is increasingly receiving more attention and makes these receptors novel and interesting targets for therapy. In this review, we cover the role of these receptors in physiological processes and will briefly discuss some implications for disease processes.
Collapse
Affiliation(s)
- Pedro H Imenez Silva
- Institute of Physiology, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland. .,National Center of Competence in Research NCCR Kidney.CH, Zurich, Switzerland.
| | - Carsten A Wagner
- Institute of Physiology, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland. .,National Center of Competence in Research NCCR Kidney.CH, Zurich, Switzerland.
| |
Collapse
|
10
|
Kadowaki M, Sato K, Kamio H, Kumagai M, Sato R, Nyui T, Umeda Y, Waseda Y, Anzai M, Aoki-Saito H, Koga Y, Hisada T, Tomura H, Okajima F, Ishizuka T. Metal-Stimulated Interleukin-6 Production Through a Proton-Sensing Receptor, Ovarian Cancer G Protein-Coupled Receptor 1, in Human Bronchial Smooth Muscle Cells: A Response Inhibited by Dexamethasone. J Inflamm Res 2021; 14:7021-7034. [PMID: 34955648 PMCID: PMC8694576 DOI: 10.2147/jir.s326964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 12/01/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose Human bronchial smooth muscle cells (BSMCs) contribute to airway obstruction and hyperresponsiveness in patients with bronchial asthma. BSMCs also generate cytokines and matricellular proteins in response to extracellular acidification through the ovarian cancer G protein-coupled receptor 1 (OGR1). Cobalt (Co) and nickel (Ni) are occupational agents, which cause occupational asthma. We examined the effects of Co and Ni on interleukin-6 (IL-6) secretion by human BSMCs because these metals may act as ligands of OGR1. Methods Human BSMCs were incubated in Dulbecco's Modified Eagle Medium (DMEM) containing 0.1% bovine serum albumin (BSA) (0.1% BSA-DMEM) for 16 hours and stimulated for the indicated time by exchanging the medium with 0.1% BSA-DMEM containing any of the metals or pH-adjusted 0.1% BSA-DMEM. IL-6 mRNA expression was quantified via reverse transcription polymerase chain reaction (RT-PCR) using the real-time TaqMan technology. IL-6 was measured using an enzyme-linked immunosorbent assay. Dexamethasone (DEX) was added 30 minutes before each stimulation. To knock down the expression of OGR1 in BSMCs, small interfering RNA (siRNA) targeting OGR1 (OGR1-siRNA) was transfected to the cells and non-targeting siRNA (NT-siRNA) was used as a control. Results Co and Ni both significantly increased IL-6 secretion in human BSMCs at 300 μM. This significant increase in IL-6 mRNA expression was observed 5 hours after stimulation. BSMCs transfected with OGR1-siRNA produced less IL-6 than BSMCs transfected with NT-siRNA in response to either Co or Ni stimulation. DEX inhibited Co- and Ni-stimulated IL-6 secretion by human BSMCs as well as pH 6.3-stimulated IL-6 secretion in a dose-dependent manner. DEX did not decrease phosphorylation of ERK1/2, p38 MAP kinase, and NF-κB p65 induced by either Co or Ni stimulation. Conclusion Co and Ni induce secretion of IL-6 in human BSMCs through activation of OGR1. Co- and Ni-stimulated IL-6 secretion is inhibited by DEX.
Collapse
Affiliation(s)
- Maiko Kadowaki
- Third Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
| | - Koichi Sato
- Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebeshi, 371-8512, Japan
| | - Hisashi Kamio
- Laboratory of Signal Transduction, Faculty of Pharmaceutical Sciences, Aomori University, Aomori, 030-0943, Japan
| | - Makoto Kumagai
- Laboratory of Signal Transduction, Faculty of Pharmaceutical Sciences, Aomori University, Aomori, 030-0943, Japan
| | - Rikishi Sato
- Laboratory of Signal Transduction, Faculty of Pharmaceutical Sciences, Aomori University, Aomori, 030-0943, Japan
| | - Takafumi Nyui
- Laboratory of Signal Transduction, Faculty of Pharmaceutical Sciences, Aomori University, Aomori, 030-0943, Japan
| | - Yukihiro Umeda
- Third Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
| | - Yuko Waseda
- Third Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
| | - Masaki Anzai
- Third Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
| | - Haruka Aoki-Saito
- Department of Respiratory Medicine, Gunma University Graduate School of Medicine, Maebeshi, 371-8511, Japan
| | - Yasuhiko Koga
- Department of Respiratory Medicine, Gunma University Graduate School of Medicine, Maebeshi, 371-8511, Japan
| | - Takeshi Hisada
- Gunma University Graduate School of Health Sciences, Maebeshi, 371-8514, Japan
| | - Hideaki Tomura
- Laboratory of Cell Signaling Regulation, Division of Life Science, School of Agriculture, Meiji University, Kawasaki, 214-8571, Japan
| | - Fumikazu Okajima
- Laboratory of Signal Transduction, Faculty of Pharmaceutical Sciences, Aomori University, Aomori, 030-0943, Japan
| | - Tamotsu Ishizuka
- Third Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
| |
Collapse
|
11
|
Nayak AP, Deshpande DA, Shah SD, Villalba DR, Yi R, Wang N, Penn RB. OGR1-dependent regulation of the allergen-induced asthma phenotype. Am J Physiol Lung Cell Mol Physiol 2021; 321:L1044-L1054. [PMID: 34668419 PMCID: PMC8715030 DOI: 10.1152/ajplung.00200.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 10/10/2021] [Accepted: 10/15/2021] [Indexed: 11/22/2022] Open
Abstract
The proton-sensing receptor, ovarian cancer G protein-coupled receptor (OGR1), has been shown to be expressed in airway smooth muscle (ASM) cells and is capable of promoting ASM contraction in response to decreased extracellular pH. OGR1 knockout (OGR1KO) mice are reported to be resistant to the asthma features induced by inhaled allergen. We recently described certain benzodiazepines as OGR1 activators capable of mediating both procontractile and prorelaxant signaling in ASM cells. Here we assess the effect of treatment with the benzodiazepines lorazepam or sulazepam on the asthma phenotype in wild-type (WT) and OGR1KO mice subjected to inhaled house dust mite (HDM; Dermatophagoides pteronyssius) challenge for 3 wk. In contrast to previously published reports, both WT and OGR1KO mice developed significant allergen-induced lung inflammation and airway hyperresponsiveness (AHR). In WT mice, treatment with sulazepam (a Gs-biased OGR1 agonist), but not lorazepam (a balanced OGR1 agonist), prevented allergen-induced AHR, although neither drug inhibited lung inflammation. The protection from development of AHR conferred by sulazepam was absent in OGR1KO mice. Treatment of WT mice with sulazepam also resulted in significant inhibition of HDM-induced collagen accumulation in the lung tissue. These findings suggest that OGR1 expression is not a requirement for development of the allergen-induced asthma phenotype, but OGR1 can be targeted by the Gs-biased OGR1 agonist sulazepam (but not the balanced agonist lorazepam) to protect from allergen-induced AHR, possibly mediated via suppression of chronic bronchoconstriction and airway remodeling in the absence of effects on airway inflammation.
Collapse
Affiliation(s)
- Ajay P Nayak
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Deepak A Deshpande
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Sushrut D Shah
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Dominic R Villalba
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Roslyn Yi
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Nadan Wang
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Raymond B Penn
- Department of Medicine, Division of Pulmonary and Critical Care Medicine & Center for Translational Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| |
Collapse
|
12
|
Nayak AP, Lim JM, Arbel E, Wang R, Villalba DR, Nguyen TL, Schaible N, Krishnan R, Tang DD, Penn RB. Cooperativity between β-agonists and c-Abl inhibitors in regulating airway smooth muscle relaxation. FASEB J 2021; 35:e21674. [PMID: 34115899 DOI: 10.1096/fj.202100154r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 04/28/2021] [Accepted: 05/03/2021] [Indexed: 01/29/2023]
Abstract
Current therapeutic approaches to avoid or reverse bronchoconstriction rely primarily on β2 adrenoceptor agonists (β-agonists) that regulate pharmacomechanical coupling/cross bridge cycling in airway smooth muscle (ASM). Targeting actin cytoskeleton polymerization in ASM represents an alternative means to regulate ASM contraction. Herein we report the cooperative effects of targeting these distinct pathways with β-agonists and inhibitors of the mammalian Abelson tyrosine kinase (Abl1 or c-Abl). The cooperative effect of β-agonists (isoproterenol) and c-Abl inhibitors (GNF-5, or imatinib) on contractile agonist (methacholine, or histamine) -induced ASM contraction was assessed in cultured human ASM cells (using Fourier Transfer Traction Microscopy), in murine precision cut lung slices, and in vivo (flexiVent in mice). Regulation of intracellular signaling that regulates contraction (pMLC20, pMYPT1, pHSP20), and actin polymerization state (F:G actin ratio) were assessed in cultured primary human ASM cells. In each (cell, tissue, in vivo) model, c-Abl inhibitors and β-agonist exhibited additive effects in either preventing or reversing ASM contraction. Treatment of contracted ASM cells with c-Abl inhibitors and β-agonist cooperatively increased actin disassembly as evidenced by a significant reduction in the F:G actin ratio. Mechanistic studies indicated that the inhibition of pharmacomechanical coupling by β-agonists is near optimal and is not increased by c-Abl inhibitors, and the cooperative effect on ASM relaxation resides in further relaxation of ASM tension development caused by actin cytoskeleton depolymerization, which is regulated by both β-agonists and c-Abl inhibitors. Thus, targeting actin cytoskeleton polymerization represents an untapped therapeutic reserve for managing airway resistance.
Collapse
Affiliation(s)
- Ajay P Nayak
- Department of Medicine, Pulmonary and Critical Care Medicine, Center for Translational Medicine, Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, USA
| | - John M Lim
- Department of Medicine, Pulmonary and Critical Care Medicine, Center for Translational Medicine, Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, USA
| | - Eylon Arbel
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Ruping Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Dominic R Villalba
- Department of Medicine, Pulmonary and Critical Care Medicine, Center for Translational Medicine, Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, USA
| | - Tahn L Nguyen
- Department of Medicine, Pulmonary and Critical Care Medicine, Center for Translational Medicine, Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, USA
| | - Niccole Schaible
- Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Ramaswamy Krishnan
- Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Dale D Tang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Raymond B Penn
- Department of Medicine, Pulmonary and Critical Care Medicine, Center for Translational Medicine, Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, USA
| |
Collapse
|
13
|
Li H, Wang S, Yao Q, Liu Y, Yang J, Xu L, Yang G. A Combined Long Noncoding RNA Signature as a Candidate Prognostic Biomarker for Ovarian Cancer. Front Oncol 2021; 11:624240. [PMID: 34123783 PMCID: PMC8191461 DOI: 10.3389/fonc.2021.624240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 05/03/2021] [Indexed: 11/13/2022] Open
Abstract
Aims Dysregulated long noncoding RNAs (lncRNAs) contributing to ovarian cancer (OC) development may serve as prognostic biomarker. We aimed to explore a lncRNA signature to serve as prognostic biomarker of OC. Methods Univariate Cox regression was conducted on the lncRNA expression dataset from the TCGA cohort, and 246 genes significantly associated with survival were retained for building a model. A random forest survival model was carried out, and a model was developed using 6 genes with the highest frequency. The selected genes were applied in a Cox multivariate regression model for prognostic prediction by calculating the risk score. We also used CCK-8, EdU, and colony formation assays to validate the function of these lncRNAs in OC cells. Results This study confirmed that the 6-lncRNA combined signature was related to OC prognosis. Systematic analysis demonstrated that lncRNA-associated genes were enriched in oncogenic signalling pathways. Five out of the 6 lncRNAs participated in OC proliferation. Conclusion We established a 6-lncRNA combined signature for OC prognosis, which may serve as powerful prognostic biomarker for OC after further validation.
Collapse
Affiliation(s)
- Hui Li
- Central Laboratory, the Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Shuoer Wang
- Department of Musculoskeletal Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Nuclear Medicine, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Qianlan Yao
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China.,Institute of Pathology, Fudan University, Shanghai, China
| | - Yan Liu
- Department of Gynecology, Weifang People's Hospital, Weifang, China
| | - Jing Yang
- Department of Anesthesiology and Postanesthesia Care Unit, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lun Xu
- Department of Musculoskeletal Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Gong Yang
- Central Laboratory, the Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China
| |
Collapse
|
14
|
Lin H, Wang J, Wen X, Wen Q, Huang S, Mai Z, Lu L, Liang X, Pan H, Li S, He Y, Ma H. A prognosis-predictive nomogram of ovarian cancer with two immune-related genes: CDC20B and PNPLA5. Oncol Lett 2020; 20:204. [PMID: 32963610 DOI: 10.3892/ol.2020.12067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 07/29/2020] [Indexed: 12/12/2022] Open
Abstract
Ovarian carcinoma (OV) is one of the most lethal gynecological malignancies globally, and the overall 5-year survival rate of OV was 47% in 2018 according to American data. To increase the survival rate of patients with OV, many researchers have sought to identify biomarkers that act as both prognosis-predictive markers and therapy targets. However, most of these have not been suitable for clinical application. The present study aimed at constructing a predictive prognostic nomogram of OV using the genes identified by combining The Cancer Genome Atlas (TCGA) dataset for OV with the immune score calculated by the Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data algorithm. Firstly, the algorithm was used to calculate the immune score of patients with OV in the TCGA-OV dataset. Secondly, differentially expressed genes (DEGs) between low and high immune score tissues were identified, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis was performed to predict the functions of these DEGs. Thirdly, univariate, multivariate and Lasso Cox's regression analyses were carried out step by step, and six prognosis-related DEGs were identified. Then, Kaplan-Myer survival curves were generated for these genes and validated by comparing their expression levels to further narrow the range of DEGs and to calculate the risk score. Two genes were identified, cell division cycle 20B and patatin-like phospholipase domain containing 5, which were both shown to have higher expression levels in OV tissues and to be significantly associated with the prognosis of OV. Next, a nomogram was created using these two genes and age, and using the receiver operating characteristic (ROC) curve and calibration curve, the effectiveness of the nomogram was validated. Finally, an external validation was conducted for this nomogram. The ROC showed that the areas under the curve (AUCs) of the 3- and 5-year overall survival predictions for the nomogram were 0.678 and 0.62, respectively. Moreover, the ROC of the external validation model showed that the AUCs of the 3- and 5-year were 0.699 and 0.643, respectively, demonstrating the effectiveness of the generated nomogram. In conclusion, the present study has identified two immune-related genes as biomarkers that reliably predict overall survival in OV. These biomarkers might also be potential molecular targets of immune therapy to treat patients with OV.
Collapse
Affiliation(s)
- Han Lin
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Jiamin Wang
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Xiaohui Wen
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Qidan Wen
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Shiya Huang
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Zhefen Mai
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Lingjing Lu
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Xingyan Liang
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Haixia Pan
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Shuna Li
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| | - Yuhong He
- Department of Gynecology of Traditional Chinese Medicine, The Affiliated Ruikang Hospital of Guangxi University of Chinese Medicine, Nanning, Guangxi 530000, P.R. China
| | - Hongxia Ma
- Department of Gynecology of Traditional Chinese Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510000, P.R. China
| |
Collapse
|
15
|
Penn RB. Mast cells in asthma: Here I am, stuck in the middle with you. Eur Respir J 2020; 56:56/1/2001337. [PMID: 32616549 PMCID: PMC7643049 DOI: 10.1183/13993003.01337-2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 05/07/2020] [Indexed: 12/24/2022]
|
16
|
Nayak AP, Penn RB. The proton-sensing receptor ovarian cancer G-protein coupled receptor 1 (OGR1) in airway physiology and disease. Curr Opin Pharmacol 2020; 51:1-10. [PMID: 32361614 DOI: 10.1016/j.coph.2020.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/22/2020] [Accepted: 03/26/2020] [Indexed: 12/28/2022]
Abstract
Numerous G protein-coupled receptors (GPCRs) regulate multiple airway functions and play fundamental roles in normal and aberrant airway and lung physiology. Thus, GPCRs are prime candidates of targeting by disease therapeutics. The intriguing proton-sensing GPCR Ovarian cancer G-protein coupled receptor 1 (OGR1; aka GPR68) has recently been shown capable of regulating airway smooth muscle (ASM) contraction and proliferation. Although the study of OGR1 has been confounded by the fact that the proton is the presumed cognate ligand of OGR1, recent studies have begun to identify novel ligands and modulators capable of regulating the diverse signaling, and functional role of OGR1. Such studies offer hope for OGR1-targeting drugs as therapeutics for obstructive lung diseases such as asthma. Herein, we review the literature to date detailing the receptor biology and pharmacology of OGR1, receptor function in the airway, and describe the potential clinical utility of OGR1-modulating drugs.
Collapse
Affiliation(s)
- Ajay P Nayak
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Thomas Jefferson University, 1020 Locust St., Suite 543G JAH, Philadelphia, PA, 19107, United States.
| | - Raymond B Penn
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Institute, Thomas Jefferson University, 1020 Locust St., Suite 543G JAH, Philadelphia, PA, 19107, United States.
| |
Collapse
|
17
|
Comprehensive Assessment of GPR68 Expression in Normal and Neoplastic Human Tissues Using a Novel Rabbit Monoclonal Antibody. Int J Mol Sci 2019; 20:ijms20215261. [PMID: 31652823 PMCID: PMC6862545 DOI: 10.3390/ijms20215261] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 10/17/2019] [Accepted: 10/22/2019] [Indexed: 02/07/2023] Open
Abstract
GPR68 (OGR1) belongs to the proton-sensing G protein-coupled receptors that are involved in cellular adaptations to pH changes during tumour development. Although expression of GPR68 has been described in many tumour cell lines, little is known about its presence in human tumour entities. We characterised the novel rabbit monoclonal anti-human GPR68 antibody 16H23L16 using various cell lines and tissue specimens. The antibody was then applied to a large series of formalin-fixed, paraffin-embedded normal and neoplastic human tissue samples. Antibody specificity was demonstrated in a Western blot analysis of GPR68-expressing cells using specific siRNAs. Immunocytochemical experiments revealed pH-dependent changes in subcellular localisation of the receptor and internalisation after stimulation with lorazepam. In normal tissue, GPR68 was present in glucagon-producing islet cells, neuroendocrine cells of the intestinal tract, gastric glands, granulocytes, macrophages, muscle layers of arteries and arterioles, and capillaries. GPR68 was also expressed in neuroendocrine tumours, where it may be a positive prognostic factor, in pheochromocytomas, cervical adenocarcinomas, and endometrial cancer, as well as in paragangliomas, medullary thyroid carcinomas, gastrointestinal stromal tumours, and pancreatic adenocarcinomas. Often, tumour capillaries were also strongly GPR68-positive. The novel antibody 16H23L16 will be a valuable tool for basic research and for identifying GPR68-expressing tumours during histopathological examinations.
Collapse
|