1
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Al Jaf AIA, Peria S, Fabiano T, Ragnini-Wilson A. Remyelinating Drugs at a Crossroad: How to Improve Clinical Efficacy and Drug Screenings. Cells 2024; 13:1326. [PMID: 39195216 DOI: 10.3390/cells13161326] [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: 06/27/2024] [Revised: 08/01/2024] [Accepted: 08/06/2024] [Indexed: 08/29/2024] Open
Abstract
Axons wrapped around the myelin sheath enable fast transmission of neuronal signals in the Central Nervous System (CNS). Unfortunately, myelin can be damaged by injury, viral infection, and inflammatory and neurodegenerative diseases. Remyelination is a spontaneous process that can restore nerve conductivity and thus movement and cognition after a demyelination event. Cumulative evidence indicates that remyelination can be pharmacologically stimulated, either by targeting natural inhibitors of Oligodendrocyte Precursor Cells (OPCs) differentiation or by reactivating quiescent Neural Stem Cells (qNSCs) proliferation and differentiation in myelinating Oligodendrocytes (OLs). Although promising results were obtained in animal models for demyelination diseases, none of the compounds identified have passed all the clinical stages. The significant number of patients who could benefit from remyelination therapies reinforces the urgent need to reassess drug selection approaches and develop strategies that effectively promote remyelination. Integrating Artificial Intelligence (AI)-driven technologies with patient-derived cell-based assays and organoid models is expected to lead to novel strategies and drug screening pipelines to achieve this goal. In this review, we explore the current literature on these technologies and their potential to enhance the identification of more effective drugs for clinical use in CNS remyelination therapies.
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Affiliation(s)
- Aland Ibrahim Ahmed Al Jaf
- Department of Biology, University of Rome "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Simone Peria
- Department of Biology, University of Rome "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Tommaso Fabiano
- Department of Biology, University of Rome "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Rome, Italy
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Antonella Ragnini-Wilson
- Department of Biology, University of Rome "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Rome, Italy
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2
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Zhang J, Liu Y, Wang C, Vander Kooi CW, Jia J. Phosphatidic acid binding to Patched contributes to the inhibition of Smoothened and Hedgehog signaling in Drosophila wing development. Sci Signal 2023; 16:eadd6834. [PMID: 37847757 PMCID: PMC10661859 DOI: 10.1126/scisignal.add6834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 09/25/2023] [Indexed: 10/19/2023]
Abstract
Hedgehog (Hh) signaling controls growth and patterning during embryonic development and homeostasis in adult tissues. Hh binding to the receptor Patched (Ptc) elicits intracellular signaling by relieving Ptc-mediated inhibition of the transmembrane protein Smoothened (Smo). We uncovered a role for the lipid phosphatidic acid (PA) in the regulation of the Hh pathway in Drosophila melanogaster. Deleting the Ptc C-terminal tail or mutating the predicted PA-binding sites within it prevented Ptc from inhibiting Smo in wing discs and in cultured cells. The C-terminal tail of Ptc directly interacted with PA in vitro, an association that was reduced by Hh, and increased the amount of PA at the plasma membrane in cultured cells. Smo also interacted with PA in vitro through a binding pocket located in the transmembrane region, and mutating residues in this pocket reduced Smo activity in vivo and in cells. By genetically manipulating PA amounts in vivo or treating cultured cells with PA, we demonstrated that PA promoted Smo activation. Our findings suggest that Ptc may sequester PA in the absence of Hh and release it in the presence of Hh, thereby increasing the amount of PA that is locally available to promote Smo activation.
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Affiliation(s)
- Jie Zhang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Yajuan Liu
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Chi Wang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Craig W. Vander Kooi
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jianhang Jia
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
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3
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Wang J, Cui B, Li X, Zhao X, Huang T, Ding X. The emerging roles of Hedgehog signaling in tumor immune microenvironment. Front Oncol 2023; 13:1171418. [PMID: 37213270 PMCID: PMC10196179 DOI: 10.3389/fonc.2023.1171418] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/26/2023] [Indexed: 05/23/2023] Open
Abstract
The Hedgehog (Hh) signaling pathway is pervasively involved in human malignancies, making it an effective target for cancer treatment for decades. In addition to its direct role in regulating cancer cell attributes, recent work indicates that it has an immunoregulatory effect on tumor microenvironments. An integrated understanding of these actions of Hh signaling pathway in tumor cells and tumor microenvironments will pave the way for novel tumor treatments and further advances in anti-tumor immunotherapy. In this review, we discuss the most recent research about Hh signaling pathway transduction, with a particular emphasis on its role in modulating tumor immune/stroma cell phenotype and function, such as macrophage polarity, T cell response, and fibroblast activation, as well as their mutual interactions between tumor cells and nonneoplastic cells. We also summarize the recent advances in the development of Hh pathway inhibitors and nanoparticle formulation for Hh pathway modulation. We suggest that targeting Hh signaling effects on both tumor cells and tumor immune microenvironments could be more synergistic for cancer treatment.
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Affiliation(s)
- Juan Wang
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai, China
| | - Baiping Cui
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai, China
| | - Xiaojie Li
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai, China
| | - Xinyue Zhao
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai, China
| | - Taomin Huang
- Department of Pharmacy, Eye & ENT Hospital, Fudan University, Shanghai, China
- *Correspondence: Taomin Huang, ; Xiaolei Ding,
| | - Xiaolei Ding
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People’s Hospital of Nantong), School of Medicine, Shanghai University, Nantong, China
- Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai, China
- *Correspondence: Taomin Huang, ; Xiaolei Ding,
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4
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Mazmanian K, Chen T, Sargsyan K, Lim C. From quantum-derived principles underlying cysteine reactivity to combating the COVID-19 pandemic. WILEY INTERDISCIPLINARY REVIEWS. COMPUTATIONAL MOLECULAR SCIENCE 2022; 12:e1607. [PMID: 35600063 PMCID: PMC9111396 DOI: 10.1002/wcms.1607] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 01/31/2022] [Accepted: 02/13/2022] [Indexed: 12/20/2022]
Abstract
The COVID-19 pandemic poses a challenge in coming up with quick and effective means to counter its cause, the SARS-CoV-2. Here, we show how the key factors governing cysteine reactivity in proteins derived from combined quantum mechanical/continuum calculations led to a novel multi-targeting strategy against SARS-CoV-2, in contrast to developing potent drugs/vaccines against a single viral target such as the spike protein. Specifically, they led to the discovery of reactive cysteines in evolutionary conserved Zn2+-sites in several SARS-CoV-2 proteins that are crucial for viral polypeptide proteolysis as well as viral RNA synthesis, proofreading, and modification. These conserved, reactive cysteines, both free and Zn2+-bound, can be targeted using the same Zn-ejector drug (disulfiram/ebselen), which enables the use of broad-spectrum anti-virals that would otherwise be removed by the virus's proofreading mechanism. Our strategy of targeting multiple, conserved viral proteins that operate at different stages of the virus life cycle using a Zn-ejector drug combined with other broad-spectrum anti-viral drug(s) could enhance the barrier to drug resistance and antiviral effects, as compared to each drug alone. Since these functionally important nonstructural proteins containing reactive cysteines are highly conserved among coronaviruses, our proposed strategy has the potential to tackle future coronaviruses. This article is categorized under:Structure and Mechanism > Reaction Mechanisms and CatalysisStructure and Mechanism > Computational Biochemistry and BiophysicsElectronic Structure Theory > Density Functional Theory.
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Affiliation(s)
| | - Ting Chen
- Institute of Biomedical Sciences Academia Sinica Taipei Taiwan
| | - Karen Sargsyan
- Institute of Biomedical Sciences Academia Sinica Taipei Taiwan
| | - Carmay Lim
- Institute of Biomedical Sciences Academia Sinica Taipei Taiwan
- Department of Chemistry National Tsing Hua University Hsinchu Taiwan
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5
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Kong Z, Xu M, Zhang Y, Huang W, Zhao X, Luo J, Song BL. The cation-π interaction in cysteine-rich domain of Smoothened is critical for its cholesterylation and function. Acta Biochim Biophys Sin (Shanghai) 2022; 54:1171-1179. [PMID: 35904215 PMCID: PMC9828284 DOI: 10.3724/abbs.2022090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 05/26/2022] [Indexed: 11/25/2022] Open
Abstract
The Hedgehog (Hh) signaling pathway is critical for embryonic development and tissue renewal. The G protein-coupled receptor (GPCR)-like protein Smoothened (SMO) is the central signal transducer in the Hh pathway. Cholesterol binds and then covalently links to the D95 residue of cysteine-rich domain (CRD) of human SMO. The cholesterylation of CRD is critical for SMO activation. SMO cholesterylation is a Ca 2+-boosted autoreaction that requires the formation of an ester bond between the side chains of D95 and Y130 as an intermediate. It is unknown whether other residues of SMO are involved in the esterification between D95 and cholesterol. In this study, we find that the SMO-CRD(27-192) can undergo cholesterylation. In addition to D95 and Y130, the residues critical for cholesterol modification include Y85, T88, T90, W109, W119, K133, E160 and F166. T88, W109, W119 and F166 also seem to be involved in protein folding. Notably, we find that Y85 and K133 form a cation-π interaction whose disruption abolishes cholesterylation and ciliary localization of SMO. This study highlights the mechanism and function of cholesterol modification of SMO.
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Affiliation(s)
- Zekai Kong
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
| | - Min Xu
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
| | - Yanqing Zhang
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
| | - Wenda Huang
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
| | - Xiaolu Zhao
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
| | - Jie Luo
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
| | - Bao-Liang Song
- />Hubei Key Laboratory of Cell HomeostasisCollege of Life SciencesTaiKang Center for Life and Medical SciencesTaiKang Medical SchoolWuhan UniversityWuhan430071China
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6
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Feng L, Pérez-Sánchez H, Bai Q. Studying noncovalent or covalent bond problem between smoothened and cholesterol by molecular dynamics simulation and Markov state model. Phys Chem Chem Phys 2022; 24:19564-19575. [PMID: 35942902 DOI: 10.1039/d2cp01453j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Smoothened (SMO) is an attractive therapeutic target for the treatment and prevention of several malignant tumors of the nervous system. The crystal structure of SMO shows cholesterol interacts with residue Asp95 via the noncovalent bond. However, some studies indicate that cholesterol covalently binds to residue Asp95 of SMO. To study these contradictory results, we performed molecular dynamics (MD) simulations and Markov state model (MSM) on SMO in complex with noncovalent-bound and covalent-bound cholesterol. The MD simulated results showed that the noncovalent-bound cholesterol was extremely unstable around the position of residue Asp95 of SMO, while the covalent-bound cholesterol could keep the stable connection with residue Asp95 of SMO. The free energy landscape showed that noncovalent-bound cholesterol had more deep energy wells than covalent-bound cholesterol when it dynamically interacted with the extracellular domain of SMO crystal structure. The MSM results showed the noncovalent-bound cholesterol had more dynamic configuration transformation pathways than the covalent-bound cholesterol. These results theoretically revealed cholesterol should have a covalent bond with residue Asp95 if cholesterol could be stable in the near position of residue Asp95 of SMO. Our studies not only elucidate the covalent binding contradictory issue between cholesterol and residue Asp95 of SMO, but also supply helpful information for antagonists design of SMO.
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Affiliation(s)
- Liya Feng
- Key Lab of Preclinical Study for New Drugs of Gansu Province, Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, Gansu, P. R. China
| | - Horacio Pérez-Sánchez
- Structural Bioinformatics and High Performance Computing Research Group (BIO-HPC), Computer Engineering Department, UCAM Universidad Católica de Murcia, Murcia, Spain.
| | - Qifeng Bai
- Key Lab of Preclinical Study for New Drugs of Gansu Province, Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, Gansu, P. R. China
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7
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Nguyen TD, Truong ME, Reiter JF. The Intimate Connection Between Lipids and Hedgehog Signaling. Front Cell Dev Biol 2022; 10:876815. [PMID: 35757007 PMCID: PMC9222137 DOI: 10.3389/fcell.2022.876815] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/13/2022] [Indexed: 01/19/2023] Open
Abstract
Hedgehog (HH) signaling is an intercellular communication pathway involved in directing the development and homeostasis of metazoans. HH signaling depends on lipids that covalently modify HH proteins and participate in signal transduction downstream. In many animals, the HH pathway requires the primary cilium, an organelle with a specialized protein and lipid composition. Here, we review the intimate connection between HH signaling and lipids. We highlight how lipids in the primary cilium can create a specialized microenvironment to facilitate signaling, and how HH and components of the HH signal transduction pathway use lipids to communicate between cells.
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Affiliation(s)
- Thi D. Nguyen
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, United States
| | - Melissa E. Truong
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Jeremy F. Reiter
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, United States,Chan Zuckerberg Biohub, San Francisco, CA, United States,*Correspondence: Jeremy F. Reiter,
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8
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Kinnebrew M, Woolley RE, Ansell TB, Byrne EFX, Frigui S, Luchetti G, Sircar R, Nachtergaele S, Mydock-McGrane L, Krishnan K, Newstead S, Sansom MSP, Covey DF, Siebold C, Rohatgi R. Patched 1 regulates Smoothened by controlling sterol binding to its extracellular cysteine-rich domain. SCIENCE ADVANCES 2022; 8:eabm5563. [PMID: 35658032 PMCID: PMC9166294 DOI: 10.1126/sciadv.abm5563] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 04/15/2022] [Indexed: 05/06/2023]
Abstract
Smoothened (SMO) transduces the Hedgehog (Hh) signal across the plasma membrane in response to accessible cholesterol. Cholesterol binds SMO at two sites: one in the extracellular cysteine-rich domain (CRD) and a second in the transmembrane domain (TMD). How these two sterol-binding sites mediate SMO activation in response to the ligand Sonic Hedgehog (SHH) remains unknown. We find that mutations in the CRD (but not the TMD) reduce the fold increase in SMO activity triggered by SHH. SHH also promotes the photocrosslinking of a sterol analog to the CRD in intact cells. In contrast, sterol binding to the TMD site boosts SMO activity regardless of SHH exposure. Mutational and computational analyses show that these sites are in allosteric communication despite being 45 angstroms apart. Hence, sterols function as both SHH-regulated orthosteric ligands at the CRD and allosteric ligands at the TMD to regulate SMO activity and Hh signaling.
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Affiliation(s)
- Maia Kinnebrew
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Rachel E. Woolley
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Eamon F. X. Byrne
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Sara Frigui
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Giovanni Luchetti
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Ria Sircar
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Sigrid Nachtergaele
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Laurel Mydock-McGrane
- Department of Developmental Biology, Washington School of Medicine, St. Louis, MO, USA
| | - Kathiresan Krishnan
- Department of Developmental Biology, Washington School of Medicine, St. Louis, MO, USA
| | - Simon Newstead
- Department of Biochemistry, University of Oxford, Oxford, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, UK
| | | | - Douglas F. Covey
- Department of Developmental Biology, Washington School of Medicine, St. Louis, MO, USA
- Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Rajat Rohatgi
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, USA
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9
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Thauvin M, de Sousa RM, Alves M, Volovitch M, Vriz S, Rampon C. An early Shh-H2O2 reciprocal regulatory interaction controls the regenerative program during zebrafish fin regeneration. J Cell Sci 2022; 135:274206. [PMID: 35107164 DOI: 10.1242/jcs.259664] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/24/2022] [Indexed: 11/20/2022] Open
Abstract
Reactive oxygen species (ROS), originally classified as toxic molecules, have attracted increasing interest given their actions in cell signaling. Hydrogen peroxide (H2O2), the major ROS produced by cells, acts as a second messenger to modify redox-sensitive proteins or lipids. After caudal fin amputation, tight spatiotemporal regulation of ROS is required first for wound healing and later to initiate the regenerative program. However, the mechanisms carrying out this sustained ROS production and their integration with signaling pathways are still poorly understood. We focused on the early dialog between H2O2 and Sonic Hedgehog (Shh) during fin regeneration. We demonstrate that H2O2 controls Shh expression and that Shh in turn regulates the H2O2 level via a canonical pathway. Moreover, the means of this tight reciprocal control change during the successive phases of the regenerative program. Dysregulation of the Hedgehog pathway has been implicated in several developmental syndromes, diabetes and cancer. These data support the existence of an early positive crosstalk between Shh and H2O2 that might be more generally involved in various processes paving the way to improve regenerative processes, particularly in vertebrates.
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Affiliation(s)
- Marion Thauvin
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, France.,Sorbonne Université, Paris, France
| | - Rodolphe Matias de Sousa
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, France.,Sorbonne Université, Paris, France
| | - Marine Alves
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, France.,Université de Paris, Faculty of Sciences, Paris, France
| | - Michel Volovitch
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, France.,École Normale Supérieure, PSL Research University, Department of Biology, Paris, France
| | - Sophie Vriz
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, France.,Université de Paris, Faculty of Sciences, Paris, France
| | - Christine Rampon
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, PSL Research University, Paris, France.,Université de Paris, Faculty of Sciences, Paris, France
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10
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Zhao F, Wu Y, Zhou F, Xue D, Zhao S, Lu W, Liu X, Hu T, Qiu Y, Li R, Gu T, Xu Y, Xu F, Zhong G, Jiang Z, Zhao S, Tao H. Elucidation of Distinct Modular Assemblies of Smoothened Receptor by Bitopic Ligand Measurement. J Med Chem 2021; 64:13830-13840. [PMID: 34492176 DOI: 10.1021/acs.jmedchem.1c01220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Class F G protein-coupled receptors are characterized by a large extracellular domain (ECD) in addition to the common transmembrane domain (TMD) with seven α-helixes. For smoothened receptor (SMO), structural studies revealed dissected ECD and TMD, and their integrated assemblies. However, distinct assemblies were reported under different circumstances. Using an unbiased approach based on four series of cross-conjugated bitopic ligands, we explore the relationship between the active status and receptor assembly. Different activity dependency on the linker length for these bitopic ligands corroborates the various occurrences of SMO assembly. These results reveal a rigid "near" assembly for active SMO, which is in contrast to previous results. Conversely, inactive SMO adopts a free ECD, which would be remotely captured at "far" assembly by cholesterol. Altogether, we propose a mechanism of cholesterol flow-caused SMO activation involving an erection of ECD from far to near assembly.
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Affiliation(s)
- Fei Zhao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Yiran Wu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Fang Zhou
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Dongxiang Xue
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Simeng Zhao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Wanglong Lu
- School of Pharmaceutical Sciences, Wuhan University, 185 Donghu Road, Wuhan, Hubei 430071, China
| | - Xiaoyan Liu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Tao Hu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yanli Qiu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Rongyan Li
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Tangjie Gu
- School of Physics Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yueming Xu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
| | - Fei Xu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Guisheng Zhong
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Zhongxing Jiang
- School of Pharmaceutical Sciences, Wuhan University, 185 Donghu Road, Wuhan, Hubei 430071, China
| | - Suwen Zhao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Houchao Tao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China
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11
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Mechanisms of Smoothened Regulation in Hedgehog Signaling. Cells 2021; 10:cells10082138. [PMID: 34440907 PMCID: PMC8391454 DOI: 10.3390/cells10082138] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/05/2021] [Accepted: 08/16/2021] [Indexed: 12/21/2022] Open
Abstract
The seven-transmembrane protein, Smoothened (SMO), has shown to be critical for the hedgehog (HH) signal transduction on the cell membrane (and the cilium in vertebrates). SMO is subjected to multiple types of post-translational regulations, including phosphorylation, ubiquitination, and sumoylation, which alter SMO intracellular trafficking and cell surface accumulation. Recently, SMO is also shown to be regulated by small molecules, such as oxysterol, cholesterol, and phospholipid. The activity of SMO must be very well balanced by these different mechanisms in vivo because the malfunction of SMO will not only cause developmental defects in early stages, but also induce cancers in late stages. Here, we discuss the activation and inactivation of SMO by different mechanisms to better understand how SMO is regulated by the graded HH signaling activity that eventually governs distinct development outcomes.
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12
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Qi X, Friedberg L, De Bose-Boyd R, Long T, Li X. Sterols in an intramolecular channel of Smoothened mediate Hedgehog signaling. Nat Chem Biol 2020; 16:1368-1375. [PMID: 32929279 PMCID: PMC7669734 DOI: 10.1038/s41589-020-0646-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 07/16/2020] [Accepted: 07/23/2020] [Indexed: 12/11/2022]
Abstract
Smoothened (SMO), a class Frizzled G protein-coupled receptor (class F GPCR), transduces the Hedgehog signal across the cell membrane. Sterols can bind to its extracellular cysteine-rich domain (CRD) and to several sites in the seven transmembrane helices (7-TMs) of SMO. However, the mechanism by which sterols regulate SMO via multiple sites is unknown. Here we determined the structures of SMO-Gi complexes bound to the synthetic SMO agonist (SAG) and to 24(S),25-epoxycholesterol (24(S),25-EC). A novel sterol-binding site in the extracellular extension of TM6 was revealed to connect other sites in 7-TMs and CRD, forming an intramolecular sterol channel from the middle side of 7-TMs to CRD. Additional structures of two gain-of-function variants, SMOD384R and SMOG111C/I496C, showed that blocking the channel at its midpoints allows sterols to occupy the binding sites in 7-TMs, thereby activating SMO. These data indicate that sterol transport through the core of SMO is a major regulator of SMO-mediated signaling.
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Affiliation(s)
- Xiaofeng Qi
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lucas Friedberg
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ryan De Bose-Boyd
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Tao Long
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Xiaochun Li
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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13
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Jiang Y, Zhuo X, Mao C. G Protein-coupled Receptors in Cancer Stem Cells. Curr Pharm Des 2020; 26:1952-1963. [DOI: 10.2174/1381612826666200305130009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 02/10/2020] [Indexed: 12/19/2022]
Abstract
G protein-coupled receptors (GPCRs) are highly expressed on a variety of tumour tissues while several
GPCR exogenous ligands become marketed pharmaceuticals. In recent decades, cancer stem cells (CSCs) become
widely investigated drug targets for cancer therapy but the underlying mechanism is still not fully elucidated.
There are vigorous participations of GPCRs in CSCs-related signalling and functions, such as biomarkers for
CSCs, activation of Wnt, Hedgehog (HH) and other signalling to facilitate CSCs progressions. This relationship
can not only uncover a novel molecular mechanism for GPCR-mediated cancer cell functions but also assist our
understanding of maintaining and modulating CSCs. Moreover, GPCR antagonists and monoclonal antibodies
could be applied to impair CSCs functions and consequently attenuate tumour growth, some of which have been
undergoing clinical studies and are anticipated to turn into marketed anticancer drugs. Therefore, this review
summarizes and provides sufficient evidences on the regulation of GPCR signalling in the maintenance, differentiation
and pluripotency of CSCs, suggesting that targeting GPCRs on the surface of CSCs could be potential
therapeutic strategies for cancer therapy.
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Affiliation(s)
- Yuhong Jiang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Xin Zhuo
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Canquan Mao
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
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14
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Qi X, Li X. Mechanistic Insights into the Generation and Transduction of Hedgehog Signaling. Trends Biochem Sci 2020; 45:397-410. [PMID: 32311334 PMCID: PMC7174405 DOI: 10.1016/j.tibs.2020.01.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/19/2020] [Accepted: 01/23/2020] [Indexed: 12/23/2022]
Abstract
Cell differentiation and proliferation require Hedgehog (HH) signaling and aberrant HH signaling causes birth defects or cancers. In this signaling pathway, the N-terminally palmitoylated and C-terminally cholesterylated HH ligand is secreted into the extracellular space with help of the Dispatched-1 (DISP1) and Scube2 proteins. The Patched-1 (PTCH1) protein releases its inhibition of the oncoprotein Smoothened (SMO) after binding the HH ligand, triggering downstream signaling events. In this review, we discuss the recent structural and biochemical studies on four major components of the HH pathway: the HH ligand, DISP1, PTCH1, and SMO. This research provides mechanistic insights into how HH signaling is generated and transduced from the cell surface into the intercellular space and will aid in facilitating the treatment of HH-related diseases.
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Affiliation(s)
- Xiaofeng Qi
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Xiaochun Li
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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15
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Ding Z, Lu W, Dai C, Huang W, Liu F, Shan W, Cheng C, Xu J, Yin Z, He W. The CRD of Frizzled 7 exhibits chondroprotective effects in osteoarthritis via inhibition of the canonical Wnt3a/β-catenin signaling pathway. Int Immunopharmacol 2020; 82:106367. [PMID: 32151961 DOI: 10.1016/j.intimp.2020.106367] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/29/2020] [Accepted: 02/29/2020] [Indexed: 12/30/2022]
Abstract
Osteoarthritis (OA) is a chronic inflammatory joint disease without effective drugs. Frizzled 7 (FzD7) binds its ligand Wnt3a through an extracellular cysteine-rich domain (CRD) to transduce the canonical Wnt/β-catenin signaling pathway, which has been strongly implicated in OA pathogenesis. Effects of recombinant protein of FzD7 CRD on Wnt/β-catenin signaling and chondral destruction was evaluated in this study. Firstly, increased protein levels of FzD7, Wnt3a and β-catenin were detected in human OA cartilage implying that the canonical Wnt/β-catenin signaling mediated by Wnt3a and FzD7 executes an essential role in OA. Then we showed that FzD7 CRD antagonized the Wnt3a/β-catenin signaling pathway in a dose-dependent manner by binding Wnt3a. In addition, FzD7 CRD increased the expression of glycosaminoglycans (GAGs), Collagen II, aggrecan and reduced the expression of matrix metalloproteinase (MMP)-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5) in Wnt3a-stimulated human chondrocytes. Furthermore, a single intra-articular injection of the FzD7 CRD was efficacious in destabilization of the medial meniscus (DMM) mouse OA model, significantly improving Osteoarthritis Research Society International (OARSI) histology scores compared to mice treated with PBS. The results indicate that the FzD7 CRD exhibits chondroprotective effects by binding Wnt3a to suppress the Wnt3a/β-catenin signaling. Targeting the FzD7 CRD may be a novel therapy for the treatment of OA.
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Affiliation(s)
- Zhenfei Ding
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China
| | - Wei Lu
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China
| | - Ce Dai
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China
| | - Wei Huang
- Department of Orthopaedics, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China
| | - Fuen Liu
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China
| | - Wenshan Shan
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China
| | - Chao Cheng
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China
| | - Jiegou Xu
- School of Basic Medical Sciences, Anhui Medical University, 81#Mei Shan Road, Hefei 230032, Anhui, China
| | - Zongsheng Yin
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, 218#Ji Xi Road, Hefei 230032, Anhui, China.
| | - Wei He
- School of Basic Medical Sciences, Anhui Medical University, 81#Mei Shan Road, Hefei 230032, Anhui, China.
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16
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Structural basis for adhesion G protein-coupled receptor Gpr126 function. Nat Commun 2020; 11:194. [PMID: 31924782 PMCID: PMC6954182 DOI: 10.1038/s41467-019-14040-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 12/11/2019] [Indexed: 12/11/2022] Open
Abstract
Many drugs target the extracellular regions (ECRs) of cell-surface receptors. The large and alternatively-spliced ECRs of adhesion G protein-coupled receptors (aGPCRs) have key functions in diverse biological processes including neurodevelopment, embryogenesis, and tumorigenesis. However, their structures and mechanisms of action remain unclear, hampering drug development. The aGPCR Gpr126/Adgrg6 regulates Schwann cell myelination, ear canal formation, and heart development; and GPR126 mutations cause myelination defects in human. Here, we determine the structure of the complete zebrafish Gpr126 ECR and reveal five domains including a previously unknown domain. Strikingly, the Gpr126 ECR adopts a closed conformation that is stabilized by an alternatively spliced linker and a conserved calcium-binding site. Alternative splicing regulates ECR conformation and receptor signaling, while mutagenesis of the calcium-binding site abolishes Gpr126 function in vivo. These results demonstrate that Gpr126 ECR utilizes a multi-faceted dynamic approach to regulate receptor function and provide relevant insights for ECR-targeted drug design. The extracellular regions (ECRs) of adhesion GPCRs have diverse biological functions, but their structures and mechanisms of action remain unclear. Here, the authors solve the ECR structure of the Gpr126 receptor and show that ECR conformation and signaling functions are regulated by alternative splicing.
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17
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Kremer L, Hennes E, Brause A, Ursu A, Robke L, Matsubayashi HT, Nihongaki Y, Flegel J, Mejdrová I, Eickhoff J, Baumann M, Nencka R, Janning P, Kordes S, Schöler HR, Sterneckert J, Inoue T, Ziegler S, Waldmann H. Discovery of the Hedgehog Pathway Inhibitor Pipinib that Targets PI4KIIIß. Angew Chem Int Ed Engl 2019; 58:16617-16628. [PMID: 31454140 PMCID: PMC6900058 DOI: 10.1002/anie.201907632] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Indexed: 01/20/2023]
Abstract
The Hedgehog (Hh) signaling pathway is crucial for vertebrate embryonic development, tissue homeostasis and regeneration. Hh signaling is upregulated in basal cell carcinoma and medulloblastoma and Hh pathway inhibitors targeting the Smoothened (SMO) protein are in clinical use. However, the signaling cascade is incompletely understood and novel druggable proteins in the pathway are in high demand. We describe the discovery of the Hh-pathway modulator Pipinib by means of cell-based screening. Target identification and validation revealed that Pipinib selectively inhibits phosphatidylinositol 4-kinase IIIβ (PI4KB) and suppresses GLI-mediated transcription and Hh target gene expression by impairing SMO translocation to the cilium. Therefore, inhibition of PI4KB and, consequently, reduction in phosphatidyl-4-phosphate levels may be considered an alternative approach to inhibit SMO function and thus, Hedgehog signaling.
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Affiliation(s)
- Lea Kremer
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Elisabeth Hennes
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Alexandra Brause
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Andrei Ursu
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
- Current address: Department of ChemistryThe Scripps Research Institute110 Scripps WayJupiterFL33458USA
| | - Lucas Robke
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
| | - Hideaki T. Matsubayashi
- Department of Cell BiologyJohns Hopkins University School of Medicine855 N. Wolfe Street, 453 RangosBaltimoreMD21205USA
| | - Yuta Nihongaki
- Department of Cell BiologyJohns Hopkins University School of Medicine855 N. Wolfe Street, 453 RangosBaltimoreMD21205USA
| | - Jana Flegel
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Ivana Mejdrová
- Institute of Organic Chemistry and BiochemistryFlemingovo nam. 216610Prague 6Czech Republic
| | - Jan Eickhoff
- Lead Discovery Center GmbHOtto-Hahn-Straße 1544227DortmundGermany
| | - Matthias Baumann
- Lead Discovery Center GmbHOtto-Hahn-Straße 1544227DortmundGermany
| | - Radim Nencka
- Institute of Organic Chemistry and BiochemistryFlemingovo nam. 216610Prague 6Czech Republic
| | - Petra Janning
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Susanne Kordes
- Lead Discovery Center GmbHOtto-Hahn-Straße 1544227DortmundGermany
- Department of Cell and Developmental BiologyMax Planck Institute for Molecular BiomedicineRöntgenstr. 2048149MünsterGermany
| | - Hans R. Schöler
- Department of Cell and Developmental BiologyMax Planck Institute for Molecular BiomedicineRöntgenstr. 2048149MünsterGermany
- Medical FacultyUniversity of MünsterDomagkstr. 348149MünsterGermany
| | - Jared Sterneckert
- Department of Cell and Developmental BiologyMax Planck Institute for Molecular BiomedicineRöntgenstr. 2048149MünsterGermany
- Technische Universität DresdenDFG-Research Center for Regenerative Therapies Dresden01307DresdenGermany
| | - Takanari Inoue
- Department of Cell BiologyJohns Hopkins University School of Medicine855 N. Wolfe Street, 453 RangosBaltimoreMD21205USA
| | - Slava Ziegler
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
| | - Herbert Waldmann
- Department of Chemical BiologyMax-Planck-Institute of Molecular PhysiologyOtto-Hahn-Straße 1144227DortmundGermany
- Faculty of Chemistry and Chemical BiologyTechnical University DortmundOtto-Hahn-Straße 644221DortmundGermany
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18
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Kremer L, Hennes E, Brause A, Ursu A, Robke L, Matsubayashi HT, Nihongaki Y, Flegel J, Mejdrová I, Eickhoff J, Baumann M, Nencka R, Janning P, Kordes S, Schöler HR, Sterneckert J, Inoue T, Ziegler S, Waldmann H. Discovery of the Hedgehog Pathway Inhibitor Pipinib that Targets PI4KIIIß. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201907632] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Lea Kremer
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Elisabeth Hennes
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Alexandra Brause
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Andrei Ursu
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
- Current address: Department of Chemistry The Scripps Research Institute 110 Scripps Way Jupiter FL 33458 USA
| | - Lucas Robke
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
| | - Hideaki T. Matsubayashi
- Department of Cell Biology Johns Hopkins University School of Medicine 855 N. Wolfe Street, 453 Rangos Baltimore MD 21205 USA
| | - Yuta Nihongaki
- Department of Cell Biology Johns Hopkins University School of Medicine 855 N. Wolfe Street, 453 Rangos Baltimore MD 21205 USA
| | - Jana Flegel
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Ivana Mejdrová
- Institute of Organic Chemistry and Biochemistry Flemingovo nam. 2 16610 Prague 6 Czech Republic
| | - Jan Eickhoff
- Lead Discovery Center GmbH Otto-Hahn-Straße 15 44227 Dortmund Germany
| | - Matthias Baumann
- Lead Discovery Center GmbH Otto-Hahn-Straße 15 44227 Dortmund Germany
| | - Radim Nencka
- Institute of Organic Chemistry and Biochemistry Flemingovo nam. 2 16610 Prague 6 Czech Republic
| | - Petra Janning
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Susanne Kordes
- Lead Discovery Center GmbH Otto-Hahn-Straße 15 44227 Dortmund Germany
- Department of Cell and Developmental Biology Max Planck Institute for Molecular Biomedicine Röntgenstr. 20 48149 Münster Germany
| | - Hans R. Schöler
- Department of Cell and Developmental Biology Max Planck Institute for Molecular Biomedicine Röntgenstr. 20 48149 Münster Germany
- Medical Faculty University of Münster Domagkstr. 3 48149 Münster Germany
| | - Jared Sterneckert
- Department of Cell and Developmental Biology Max Planck Institute for Molecular Biomedicine Röntgenstr. 20 48149 Münster Germany
- Technische Universität Dresden DFG-Research Center for Regenerative Therapies Dresden 01307 Dresden Germany
| | - Takanari Inoue
- Department of Cell Biology Johns Hopkins University School of Medicine 855 N. Wolfe Street, 453 Rangos Baltimore MD 21205 USA
| | - Slava Ziegler
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
| | - Herbert Waldmann
- Department of Chemical Biology Max-Planck-Institute of Molecular Physiology Otto-Hahn-Straße 11 44227 Dortmund Germany
- Faculty of Chemistry and Chemical Biology Technical University Dortmund Otto-Hahn-Straße 6 44221 Dortmund Germany
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19
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Zhang J, Liu Y, Jiang K, Jia J. Hedgehog signaling promotes lipolysis in adipose tissue through directly regulating Bmm/ATGL lipase. Dev Biol 2019; 457:128-139. [PMID: 31550483 DOI: 10.1016/j.ydbio.2019.09.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/21/2019] [Accepted: 09/20/2019] [Indexed: 01/20/2023]
Abstract
Hedgehog (Hh) signaling has been shown to regulate multiple developmental processes, however, it is unclear how it regulates lipid metabolism. Here, we demonstrate that Hh signaling exhibits potent activity in Drosophila fat body, which is induced by both locally expressed and midgut-derived Hh proteins. Inactivation of Hh signaling increases, whereas activation of Hh signaling decreases lipid accumulation. The major lipase Brummer (Bmm) acts downstream of Smoothened (Smo) in Hh signaling to promote lipolysis, therefore, the breakdown of triacylglycerol (TAG). We identify a critical Ci binding site in bmm promoter that is responsible to mediate Bmm expression induced by Hh signaling. Genomic mutation of the Ci binding site significantly reduces the expression of Bmm and dramatically decreases the responsiveness to Ci overexpression. Together, our findings provide a model for lipolysis to be regulated by Hh signaling, raising the possibility for Hh signaling to be involved in lipid metabolic and/or lipid storage diseases.
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Affiliation(s)
- Jie Zhang
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Yajuan Liu
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Kai Jiang
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, 40536, USA
| | - Jianhang Jia
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, 40536, USA.
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20
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Zhang J, Li Y, Fan Y, Wu D, Xu J. Compound heterozygous mutations in SMO associated with anterior segment dysgenesis and morning glory syndrome. Gene 2019; 713:143973. [DOI: 10.1016/j.gene.2019.143973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/09/2019] [Accepted: 07/09/2019] [Indexed: 12/11/2022]
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21
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Kowatsch C, Woolley RE, Kinnebrew M, Rohatgi R, Siebold C. Structures of vertebrate Patched and Smoothened reveal intimate links between cholesterol and Hedgehog signalling. Curr Opin Struct Biol 2019; 57:204-214. [PMID: 31247512 PMCID: PMC6744280 DOI: 10.1016/j.sbi.2019.05.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/16/2019] [Accepted: 05/18/2019] [Indexed: 12/21/2022]
Abstract
The Hedgehog (HH) signalling pathway is a cell-cell communication system that controls the patterning of multiple tissues during embryogenesis in metazoans. In adults, HH signals regulate tissue stem cells and regenerative responses. Abnormal signalling can cause birth defects and cancer. The HH signal is received on target cells by Patched (PTCH1), the receptor for HH ligands, and then transmitted across the plasma membrane by Smoothened (SMO). Recent structural and biochemical studies have pointed to a sterol lipid, likely cholesterol itself, as the elusive second messenger that communicates the HH signal between PTCH1 and SMO, thus linking ligand reception to transmembrane signalling.
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Affiliation(s)
- Christiane Kowatsch
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Rachel E Woolley
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Maia Kinnebrew
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, United States
| | - Rajat Rohatgi
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, United States.
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.
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22
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Hu A, Song BL. The interplay of Patched, Smoothened and cholesterol in Hedgehog signaling. Curr Opin Cell Biol 2019; 61:31-38. [PMID: 31369952 DOI: 10.1016/j.ceb.2019.06.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/29/2019] [Accepted: 06/30/2019] [Indexed: 12/29/2022]
Abstract
The Hedgehog (HH) pathway plays a pivotal role in regulating a diverse array of events from embryonic tissue patterning to adult organ self-renewal. Aberrant activation of the pathway is linked to carcinogenesis. Key factors in the HH pathway include the signaling ligand HH, the receptor Patched (PTCH), and the G-protein-coupled receptor-like transducer Smoothened (SMO). A long-lasting question about this pathway is how PTCH prevents SMO from being activated. Recent high-resolution structural studies provide insight into the molecular basis of HH recognition by PTCH. Moreover, cholesterol stands out as the endogenous ligand of SMO and acts by binding and/or covalently linking to SMO. In this review, we discuss current advances in HH signaling, the interplay of PTCH, SMO and cholesterol, and propose putative models of SMO activation by cholesterol binding and/or modification.
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Affiliation(s)
- Ao Hu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Bao-Liang Song
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China.
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23
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An X, Bai Q, Bai F, Shi D, Liu H, Yao X. Deciphering the Allosteric Effect of Antagonist Vismodegib on Smoothened Receptor Deactivation Using Metadynamics Simulation. Front Chem 2019; 7:406. [PMID: 31214579 PMCID: PMC6558189 DOI: 10.3389/fchem.2019.00406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 05/20/2019] [Indexed: 01/12/2023] Open
Abstract
The smoothened receptor (Smo) plays a key role in Hedgehog (Hh) signaling pathway and it has been regarded as an efficacious therapeutic target for basal cell carcinoma (BCC) and medulloblastoma (MB). Nevertheless, the resistance mutation and active mutants of Smo have put forward the requirement of finding more effective inhibitors. Herein, we performed metadynamics simulations on Smo bound with vismodegib (Smo-Vismod) and with cholesterol (Smo-CLR), respectively, to explore the inhibition mechanism of vismodegib. The simulation results indicated that vismodegib-induced shifts of TM5, TM6, and TM7, which permitted the extracellular extension of TM6 and extracellular loop3 (ECL3) to enter the extracellular cysteine-rich domain (CRD) groove. Therefore, an open CRD groove that has not been noticed previously was observed in Smo-Vismod complex. As a consequence, the occupied CRD groove prevents the binding of cholesterol. In addition, the HD and ECLs play crucial roles in the interaction of CRD and TMD. These results reveal that TM5, TM6, and TM7 play important roles in allosteric inhibition the activation of Smo and disrupting cholesterol binding by vismodegib binding. Our results are expected to contribute to understanding the allosteric inhibition mechanism of Smo by vismodegib. Moreover, the detailed conformational changes contribute to the development of novel Smo inhibitors against resistance mutation and active mutants of Smo.
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Affiliation(s)
- Xiaoli An
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou, China
| | - Qifeng Bai
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou, China
| | - Fang Bai
- School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Danfeng Shi
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou, China
| | - Huanxiang Liu
- School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Xiaojun Yao
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou, China.,State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau, China
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Abstract
Signaling pathways that mediate cell-cell communication are essential for collective cell behaviors in multicellular systems. The hedgehog (HH) pathway, first discovered and elucidated in Drosophila, is one of these iconic signaling systems that plays many roles during embryogenesis and in adults; abnormal HH signaling can lead to birth defects and cancer. We review recent structural and biochemical studies that have advanced our understanding of the vertebrate HH pathway, focusing on the mechanisms by which the HH signal is received by patched on target cells, transduced across the cell membrane by smoothened, and transmitted to the nucleus by GLI proteins to influence gene-expression programs.
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Affiliation(s)
- Jennifer H Kong
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Rajat Rohatgi
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
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25
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Galperin I, Dempwolff L, Diederich WE, Lauth M. Inhibiting Hedgehog: An Update on Pharmacological Compounds and Targeting Strategies. J Med Chem 2019; 62:8392-8411. [DOI: 10.1021/acs.jmedchem.9b00188] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ilya Galperin
- Center for Tumor and Immune Biology (ZTI), Philipps University Marburg, Hans-Meerwein-Straße 3, 35043 Marburg, Germany
| | - Lukas Dempwolff
- School of Pharmacy, Center for Tumor and Immune Biology (ZTI), Philipps University Marburg, Hans-Meerwein-Straße 3, 35043 Marburg, Germany
| | - Wibke E. Diederich
- School of Pharmacy, Center for Tumor and Immune Biology (ZTI), Philipps University Marburg, Hans-Meerwein-Straße 3, 35043 Marburg, Germany
- Core Facility Medicinal Chemistry, Philipps University Marburg, Hans-Meerwein-Straße 3, 35043 Marburg, Germany
| | - Matthias Lauth
- Center for Tumor and Immune Biology (ZTI), Philipps University Marburg, Hans-Meerwein-Straße 3, 35043 Marburg, Germany
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26
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State of the art of Smo antagonists for cancer therapy: advances in the target receptor and new ligand structures. Future Med Chem 2019; 11:617-638. [PMID: 30912670 DOI: 10.4155/fmc-2018-0497] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Since the Hedgehog signaling pathway has been associated with cancer, it has emerged as a therapeutic target for cancer therapy. The main target among the key Hedgehog proteins is the GPCR-like Smo receptor. Therefore, some Smo antagonists that have entered clinical trials, including the US FDA-approved drugs vismodegib and sonidegib, to treat basal cell carcinoma and medulloblastoma. However, early resistance of these drugs has spawned the need to understand the molecular bases of this phenomena. We therefore reviewed details about Smo receptor structures and the best Smo antagonist chemical structures. In addition, we discussed strategies that should be considered to develop new, safer generations of Smo antagonists that avoid current clinical limitations.
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27
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Pietrobono S, Stecca B. Targeting the Oncoprotein Smoothened by Small Molecules: Focus on Novel Acylguanidine Derivatives as Potent Smoothened Inhibitors. Cells 2018; 7:cells7120272. [PMID: 30558232 PMCID: PMC6316656 DOI: 10.3390/cells7120272] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 11/30/2018] [Accepted: 12/10/2018] [Indexed: 12/13/2022] Open
Abstract
Hedgehog-GLI (HH) signaling was originally identified as a critical morphogenetic pathway in embryonic development. Since its discovery, a multitude of studies have reported that HH signaling also plays key roles in a variety of cancer types and in maintaining tumor-initiating cells. Smoothened (SMO) is the main transducer of HH signaling, and in the last few years, it has emerged as a promising therapeutic target for anticancer therapy. Although vismodegib and sonidegib have demonstrated effectiveness for the treatment of basal cell carcinoma (BCC), their clinical use has been hampered by severe side effects, low selectivity against cancer stem cells, and the onset of mutation-driven drug resistance. Moreover, SMO antagonists are not effective in cancers where HH activation is due to mutations of pathway components downstream of SMO, or in the case of noncanonical, SMO-independent activation of the GLI transcription factors, the final mediators of HH signaling. Here, we review the current and rapidly expanding field of SMO small-molecule inhibitors in experimental and clinical settings, focusing on a class of acylguanidine derivatives. We also discuss various aspects of SMO, including mechanisms of resistance to SMO antagonists.
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Affiliation(s)
- Silvia Pietrobono
- Tumor Cell Biology Unit⁻Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), 50139 Florence, Italy.
| | - Barbara Stecca
- Tumor Cell Biology Unit⁻Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), 50139 Florence, Italy.
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28
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Overcoming the emerging drug resistance of smoothened: an overview of small-molecule SMO antagonists with antiresistance activity. Future Med Chem 2018; 10:2855-2875. [PMID: 30557039 DOI: 10.4155/fmc-2018-0200] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Hedgehog (HH) signaling pathway plays vital roles in controlling embryonic cell fate and homeostatic, and becomes dormant in mature individuals, aberrant activation of HH signaling pathway is involved in a number of human cancers. Smoothened (SMO), a vital transducer of HH signaling pathway, attracts significant attentions in HH signaling pathway-related cancer therapy. The approval of SMO antagonists vismodegib proves that SMO is a promising therapeutic target, and a number of SMO antagonists are reported since then. However, high incidence of tumor recurrence with the clinical application of vismodegib urges exploring of novel drugs with antiresistance profiles. This review provides an overview of SMO mutations reported in the literature, crystal structures of SMO, as well as reported antagonists with antiresistance profiles.
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29
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Zhang X, Dong S, Xu F. Structural and Druggability Landscape of Frizzled G Protein-Coupled Receptors. Trends Biochem Sci 2018; 43:1033-1046. [DOI: 10.1016/j.tibs.2018.09.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/07/2018] [Accepted: 09/11/2018] [Indexed: 12/29/2022]
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30
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Bariwal J, Kumar V, Dong Y, Mahato RI. Design of Hedgehog pathway inhibitors for cancer treatment. Med Res Rev 2018; 39:1137-1204. [PMID: 30484872 DOI: 10.1002/med.21555] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 12/11/2022]
Abstract
Hedgehog (Hh) signaling is involved in the initiation and progression of various cancers and is essential for embryonic and postnatal development. This pathway remains in the quiescent state in adult tissues but gets activated upon inflammation and injuries. Inhibition of Hh signaling pathway using natural and synthetic compounds has provided an attractive approach for treating cancer and inflammatory diseases. While the majority of Hh pathway inhibitors target the transmembrane protein Smoothened (SMO), some small molecules that target the signaling cascade downstream of SMO are of particular interest. Substantial efforts are being made to develop new molecules targeting various components of the Hh signaling pathway. Here, we have discussed the discovery of small molecules as Hh inhibitors from the diverse chemical background. Also, some of the recently identified natural products have been included as a separate section. Extensive structure-activity relationship (SAR) of each chemical class is the focus of this review. Also, clinically advanced molecules are discussed from the last 5 to 7 years. Nanomedicine-based delivery approaches for Hh pathway inhibitors are also discussed concisely.
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Affiliation(s)
- Jitender Bariwal
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska
| | - Virender Kumar
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska
| | - Yuxiang Dong
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska
| | - Ram I Mahato
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska
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31
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Valnohova J, Kowalski-Jahn M, Sunahara RK, Schulte G. Functional dissection of the N-terminal extracellular domains of Frizzled 6 reveals their roles for receptor localization and Dishevelled recruitment. J Biol Chem 2018; 293:17875-17887. [PMID: 30237173 PMCID: PMC6240854 DOI: 10.1074/jbc.ra118.004763] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/18/2018] [Indexed: 11/06/2022] Open
Abstract
The Frizzled (FZD) proteins belong to class F of G protein-coupled receptors (GPCRs) and are essential for various pathways involving the secreted lipoglycoproteins of the wingless/int-1 (WNT) family. A WNT-binding cysteine-rich domain (CRD) in FZDs is N-terminally located and connected to the seven transmembrane domain-spanning receptor core by a linker domain that has a variable length in different FZD homologs. However, the function and importance of this linker domain are poorly understood. Here we used systematic mutagenesis of FZD6 to define the minimal N-terminal domain sufficient for receptor surface expression and recruitment of the intracellular scaffold protein Dishevelled (DVL). Further, we identified a triad of evolutionarily conserved cysteines in the FZD linker domain that is crucial for receptor membrane expression and recruitment of DVL. Our results are in agreement with the concept that the conserved cysteines in the linker domain of FZDs assist with the formation of a common secondary structure in this region. We propose that this structure could be involved in agonist binding and receptor activation mechanisms that are similar to the binding and activation mechanisms known for other GPCRs.
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Affiliation(s)
- Jana Valnohova
- From the Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Maria Kowalski-Jahn
- From the Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Roger K Sunahara
- Department of Pharmacology, University of California San Diego School of Medicine, La Jolla, California 92093
| | - Gunnar Schulte
- From the Section for Receptor Biology and Signaling, Department of Physiology and Pharmacology, Karolinska Institutet, 171 65 Stockholm, Sweden.
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32
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Hedgehog Signaling in Cancer: A Prospective Therapeutic Target for Eradicating Cancer Stem Cells. Cells 2018; 7:cells7110208. [PMID: 30423843 PMCID: PMC6262325 DOI: 10.3390/cells7110208] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/03/2018] [Accepted: 11/05/2018] [Indexed: 02/07/2023] Open
Abstract
The Hedgehog (Hh) pathway is a signaling cascade that plays a crucial role in many fundamental processes, including embryonic development and tissue homeostasis. Moreover, emerging evidence has suggested that aberrant activation of Hh is associated with neoplastic transformations, malignant tumors, and drug resistance of a multitude of cancers. At the molecular level, it has been shown that Hh signaling drives the progression of cancers by regulating cancer cell proliferation, malignancy, metastasis, and the expansion of cancer stem cells (CSCs). Thus, a comprehensive understanding of Hh signaling during tumorigenesis and development of chemoresistance is necessary in order to identify potential therapeutic strategies to target various human cancers and their relapse. In this review, we discuss the molecular basis of the Hh signaling pathway and its abnormal activation in several types of human cancers. We also highlight the clinical development of Hh signaling inhibitors for cancer therapy as well as CSC-targeted therapy.
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33
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Byrne EF, Luchetti G, Rohatgi R, Siebold C. Multiple ligand binding sites regulate the Hedgehog signal transducer Smoothened in vertebrates. Curr Opin Cell Biol 2018; 51:81-88. [PMID: 29268141 PMCID: PMC5949240 DOI: 10.1016/j.ceb.2017.10.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 10/16/2017] [Indexed: 12/31/2022]
Abstract
The Hedgehog (Hh) pathway plays a central role in the development of multicellular organisms, guiding cell differentiation, proliferation and survival. While many components of the vertebrate pathway were discovered two decades ago, the mechanism by which the Hh signal is transmitted across the plasma membrane remains mysterious. This fundamental task in signalling is carried out by Smoothened (SMO), a human oncoprotein and validated cancer drug target that is a member of the G-protein coupled receptor protein family. Recent structural and functional studies have advanced our mechanistic understanding of SMO activation, revealing its unique regulation by two separable but allosterically-linked ligand-binding sites. Unexpectedly, these studies have nominated cellular cholesterol as having an instructive role in SMO signalling.
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Affiliation(s)
- Eamon Fx Byrne
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Giovanni Luchetti
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, United States
| | - Rajat Rohatgi
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA, United States.
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.
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34
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Arensdorf AM, Dillard ME, Menke JM, Frank MW, Rock CO, Ogden SK. Sonic Hedgehog Activates Phospholipase A2 to Enhance Smoothened Ciliary Translocation. Cell Rep 2018; 19:2074-2087. [PMID: 28591579 DOI: 10.1016/j.celrep.2017.05.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 03/30/2017] [Accepted: 05/09/2017] [Indexed: 12/21/2022] Open
Abstract
The G protein-coupled receptor Smoothened (Smo) is the signal transducer of the Sonic Hedgehog (Shh) pathway. Smo signals through G protein-dependent and -independent routes, with G protein-independent canonical signaling to Gli effectors requiring Smo accumulation in the primary cilium. The mechanisms controlling Smo activation and trafficking are not yet clear but likely entail small-molecule binding to pockets in its extracellular cysteine-rich domain (CRD) and/or transmembrane bundle. Here, we demonstrate that the cytosolic phospholipase cPLA2α is activated through Gβγ downstream of Smo to release arachidonic acid. Arachidonic acid binds Smo and synergizes with CRD-binding agonists, promoting Smo ciliary trafficking and high-level signaling. Chemical or genetic cPLA2α inhibition dampens Smo signaling to Gli, revealing an unexpected contribution of G protein-dependent signaling to canonical pathway activity. Arachidonic acid displaces the Smo transmembrane domain inhibitor cyclopamine to rescue CRD agonist-induced signaling, suggesting that arachidonic acid may target the transmembrane bundle to allosterically enhance signaling by CRD agonist-bound Smo.
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Affiliation(s)
- Angela M Arensdorf
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Miriam E Dillard
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jacob M Menke
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Rhodes College St. Jude Summer Plus Program, Rhodes College, Memphis, TN 38112, USA
| | - Matthew W Frank
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Charles O Rock
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Stacey K Ogden
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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35
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Skoda AM, Simovic D, Karin V, Kardum V, Vranic S, Serman L. The role of the Hedgehog signaling pathway in cancer: A comprehensive review. Bosn J Basic Med Sci 2018; 18:8-20. [PMID: 29274272 DOI: 10.17305/bjbms.2018.2756] [Citation(s) in RCA: 435] [Impact Index Per Article: 72.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 12/01/2017] [Indexed: 12/14/2022] Open
Abstract
The Hedgehog (Hh) signaling pathway was first identified in the common fruit fly. It is a highly conserved evolutionary pathway of signal transmission from the cell membrane to the nucleus. The Hh signaling pathway plays an important role in the embryonic development. It exerts its biological effects through a signaling cascade that culminates in a change of balance between activator and repressor forms of glioma-associated oncogene (Gli) transcription factors. The components of the Hh signaling pathway involved in the signaling transfer to the Gli transcription factors include Hedgehog ligands (Sonic Hh [SHh], Indian Hh [IHh], and Desert Hh [DHh]), Patched receptor (Ptch1, Ptch2), Smoothened receptor (Smo), Suppressor of fused homolog (Sufu), kinesin protein Kif7, protein kinase A (PKA), and cyclic adenosine monophosphate (cAMP). The activator form of Gli travels to the nucleus and stimulates the transcription of the target genes by binding to their promoters. The main target genes of the Hh signaling pathway are PTCH1, PTCH2, and GLI1. Deregulation of the Hh signaling pathway is associated with developmental anomalies and cancer, including Gorlin syndrome, and sporadic cancers, such as basal cell carcinoma, medulloblastoma, pancreatic, breast, colon, ovarian, and small-cell lung carcinomas. The aberrant activation of the Hh signaling pathway is caused by mutations in the related genes (ligand-independent signaling) or by the excessive expression of the Hh signaling molecules (ligand-dependent signaling - autocrine or paracrine). Several Hh signaling pathway inhibitors, such as vismodegib and sonidegib, have been developed for cancer treatment. These drugs are regarded as promising cancer therapies, especially for patients with refractory/advanced cancers.
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Affiliation(s)
- Ana Marija Skoda
- Department of Biology, School of Medicine, University of Zagreb, Zagreb, Croatia.
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36
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Diepenhorst N, Rueda P, Cook AE, Pastoureau P, Sabatini M, Langmead CJ. G protein-coupled receptors as anabolic drug targets in osteoporosis. Pharmacol Ther 2017; 184:1-12. [PMID: 29080701 DOI: 10.1016/j.pharmthera.2017.10.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Osteoporosis is a progressive bone disorder characterised by imbalance between bone building (anabolism) and resorption (catabolism). Most therapeutics target inhibition of osteoclast-mediated bone resorption, but more recent attention in early drug discovery has focussed on anabolic targets in osteoblasts or their precursors. Two marketed agents that display anabolic properties, strontium ranelate and teriparatide, mediate their actions via the G protein-coupled calcium-sensing and parathyroid hormone-1 receptors, respectively. This review explores their activity, the potential for improved therapeutics targeting these receptors and other putative anabolic GPCR targets, including Smoothened, Wnt/Frizzled, relaxin family peptide, adenosine, cannabinoid, prostaglandin and sphingosine-1-phosphate receptors.
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Affiliation(s)
- Natalie Diepenhorst
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, VIC 3052, Australia
| | - Patricia Rueda
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, VIC 3052, Australia
| | - Anna E Cook
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, VIC 3052, Australia
| | - Philippe Pastoureau
- Therapeutic Innovation Pole of Immuno-Inflammatory Diseases, Institut de Recherches Servier, Suresnes, France
| | - Massimo Sabatini
- Therapeutic Innovation Pole of Immuno-Inflammatory Diseases, Institut de Recherches Servier, Suresnes, France
| | - Christopher J Langmead
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, VIC 3052, Australia.
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37
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Deol GSJ, Cuthbert TN, Gatie MI, Spice DM, Hilton LR, Kelly GM. Wnt and Hedgehog Signaling Regulate the Differentiation of F9 Cells into Extraembryonic Endoderm. Front Cell Dev Biol 2017; 5:93. [PMID: 29119099 PMCID: PMC5660979 DOI: 10.3389/fcell.2017.00093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 10/09/2017] [Indexed: 01/24/2023] Open
Abstract
Mouse F9 cells differentiate into primitive extraembryonic endoderm (PrE) when treated with retinoic acid (RA), and this is accompanied by an up-regulation of Gata6. The role of the GATA6 network in PrE differentiation is known, and we have shown it directly activates Wnt6. Canonical Wnt/β-catenin signaling is required by F9 cells to differentiate to PrE, and this, like most developmental processes, requires input from one or more additional pathways. We found both RA and Gata6 overexpression, can induce the expression of Indian Hedgehog (Ihh) and a subset of its target genes through Gli activation during PrE induction. Chemical activation of the Hh pathway using a Smoothened agonist (SAG) also increased Gli reporter activity, and as expected, when Hh signaling was blocked with a Smoothened antagonist, cyclopamine, this RA-induced reporter activity was reduced. Interestingly, SAG alone failed to induce markers of PrE differentiation, and had no effect on Wnt/β-catenin-dependent TCF-LEF reporter activity. The expected increase in Wnt/β-catenin-dependent TCF-LEF reporter activity and PrE markers induced by RA was, however, blocked by cyclopamine. Finally, inhibiting GSK3 activity with BIO increased both TCF-LEF and Gli reporter activities. Together, we demonstrate the involvement of Hh signaling in the RA-induced differentiation of F9 cells into PrE, and while the activation of the Hh pathway itself is not sufficient, it as well as active Wnt/β-catenin are necessary for F9 cell differentiation.
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Affiliation(s)
- Gurjoth S J Deol
- Molecular Genetics Unit, Department of Biology, University of Western Ontario, London, ON, Canada
| | - Tina N Cuthbert
- Molecular Genetics Unit, Department of Biology, University of Western Ontario, London, ON, Canada
| | - Mohamed I Gatie
- Molecular Genetics Unit, Department of Biology, University of Western Ontario, London, ON, Canada
| | - Danielle M Spice
- Molecular Genetics Unit, Department of Biology, University of Western Ontario, London, ON, Canada
| | - Lindsay R Hilton
- Molecular Genetics Unit, Department of Biology, University of Western Ontario, London, ON, Canada
| | - Gregory M Kelly
- Molecular Genetics Unit, Department of Biology, University of Western Ontario, London, ON, Canada.,Child Health Research Institute, London, ON, Canada.,Ontario Institute for Regenerative Medicine, Toronto, ON, Canada
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38
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Abstract
Communication between cells pervades the development and physiology of metazoans. In animals, this process is carried out by a relatively small number of signaling pathways, each consisting of a chain of biochemical events through which extracellular stimuli control the behavior of target cells. One such signaling system is the Hedgehog pathway, which is crucial in embryogenesis and is implicated in many birth defects and cancers. Although Hedgehog pathway components were identified by genetic analysis more than a decade ago, our understanding of the molecular mechanisms of signaling is far from complete. In this review, we focus on the biochemistry and cell biology of the Hedgehog pathway. We examine the unique biosynthesis of the Hedgehog ligand, its specialized release from cells into extracellular space, and the poorly understood mechanisms involved in ligand reception and pathway activation at the surface of target cells. We highlight several critical questions that remain open.
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Affiliation(s)
- Kostadin Petrov
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115; ,
| | - Bradley M Wierbowski
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115; ,
| | - Adrian Salic
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115; ,
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39
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Ye L, Ding K, Zhao F, Liu X, Wu Y, Liu Y, Xue D, Zhou F, Zhang X, Stevens RC, Xu F, Zhao S, Tao H. A structurally guided dissection-then-evolution strategy for ligand optimization of smoothened receptor. MEDCHEMCOMM 2017; 8:1332-1336. [PMID: 30108845 PMCID: PMC6072208 DOI: 10.1039/c7md00104e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/20/2017] [Indexed: 01/18/2023]
Abstract
We present herein a novel dissection-then-evolution strategy for ligand optimization. Using the co-crystal structure of the smoothened receptor (SMO) as a guide, we studied the modular contribution of LY2940680 by systematically "silencing" the specific interaction between the individual residue(s) and the fragment in the ligand. Following evolution by focusing on the benzoyl part finally yielded an improved ligand 21.
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Affiliation(s)
- Lintao Ye
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- Shanghai Institute of Materia Medica , Chinese Academy of Sciences , 555 Zuchongzhi Road, Building 3, Room 426 , Shanghai , 201203 , China
- University of Chinese Academy of Sciences , No. 19A, Yuquan Road , Beijing 100049 , China
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Kang Ding
- Key Laboratory of Computational Biology , CAS-MPG Partner Institute for Computational Biology , Shanghai Institutes for Biological Sciences , Chinese Academy of Sciences , Shanghai , 200031 , China
- University of Chinese Academy of Sciences , No. 19A, Yuquan Road , Beijing 100049 , China
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Fei Zhao
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
| | - Xiaoyan Liu
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
| | - Yiran Wu
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
| | - Yang Liu
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
| | - Dongxiang Xue
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- Shanghai Institute of Materia Medica , Chinese Academy of Sciences , 555 Zuchongzhi Road, Building 3, Room 426 , Shanghai , 201203 , China
- University of Chinese Academy of Sciences , No. 19A, Yuquan Road , Beijing 100049 , China
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Fang Zhou
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- Shanghai Institute of Materia Medica , Chinese Academy of Sciences , 555 Zuchongzhi Road, Building 3, Room 426 , Shanghai , 201203 , China
- University of Chinese Academy of Sciences , No. 19A, Yuquan Road , Beijing 100049 , China
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Xianjun Zhang
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- Institute of Biochemistry and Cell Biology , Shanghai Institutes for Biological Sciences , Chinese Academy of Sciences , Shanghai , 200031 , China
- University of Chinese Academy of Sciences , No. 19A, Yuquan Road , Beijing 100049 , China
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Raymond C Stevens
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Fei Xu
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Suwen Zhao
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
- School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China
| | - Houchao Tao
- iHuman Institute , ShanghaiTech University , 2F Building 6, 99 Haike Road, Pudong New District , Shanghai 201210 , China . ;
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Zhang X, Zhao F, Wu Y, Yang J, Han GW, Zhao S, Ishchenko A, Ye L, Lin X, Ding K, Dharmarajan V, Griffin PR, Gati C, Nelson G, Hunter MS, Hanson MA, Cherezov V, Stevens RC, Tan W, Tao H, Xu F. Crystal structure of a multi-domain human smoothened receptor in complex with a super stabilizing ligand. Nat Commun 2017; 8:15383. [PMID: 28513578 PMCID: PMC5442369 DOI: 10.1038/ncomms15383] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 03/24/2017] [Indexed: 02/06/2023] Open
Abstract
The Smoothened receptor (SMO) belongs to the Class Frizzled of the G protein-coupled receptor (GPCR) superfamily, constituting a key component of the Hedgehog signalling pathway. Here we report the crystal structure of the multi-domain human SMO, bound and stabilized by a designed tool ligand TC114, using an X-ray free-electron laser source at 2.9 Å. The structure reveals a precise arrangement of three distinct domains: a seven-transmembrane helices domain (TMD), a hinge domain (HD) and an intact extracellular cysteine-rich domain (CRD). This architecture enables allosteric interactions between the domains that are important for ligand recognition and receptor activation. By combining the structural data, molecular dynamics simulation, and hydrogen-deuterium-exchange analysis, we demonstrate that transmembrane helix VI, extracellular loop 3 and the HD play a central role in transmitting the signal employing a unique GPCR activation mechanism, distinct from other multi-domain GPCRs. Smoothened receptors (SMO) play a key role in the Hedgehog signalling pathway. Here the authors present the structure of a multi-domain human SMO with a rationally designed stabilizing ligand bound in the transmembrane domain of the receptor, and propose a model for SMO activation.
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Affiliation(s)
- Xianjun Zhang
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.,Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fei Zhao
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China
| | - Yiran Wu
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China
| | - Jun Yang
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Gye Won Han
- Departments of Chemistry, Biological Sciences and Physics &Astronomy, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA
| | - Suwen Zhao
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Andrii Ishchenko
- Departments of Chemistry, Biological Sciences and Physics &Astronomy, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA
| | - Lintao Ye
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.,Shanghai Institute of Materia Medica, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 555 Zuchongzhi Lu, Building 3, Room 426, Shanghai 201203, China
| | - Xi Lin
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.,Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kang Ding
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.,Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | | | - Patrick R Griffin
- Department of Molecular Therapeutics, The Scripps Research Institute, 130 Scripps Way, Jupiter, Florida 33458, USA
| | - Cornelius Gati
- Medical Research Council, Laboratory of Molecular Biology, Cambridge, Biomedical Campus, Francis Crick Avenue, Cambridge CB2 OQH, UK
| | - Garrett Nelson
- Department of Physics, Arizona State University, Tempe, Arizona 85287, USA
| | - Mark S Hunter
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | | | - Vadim Cherezov
- Departments of Chemistry, Biological Sciences and Physics &Astronomy, Bridge Institute, University of Southern California, Los Angeles, California 90089, USA
| | - Raymond C Stevens
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Wenfu Tan
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Houchao Tao
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China
| | - Fei Xu
- iHuman Institute, ShanghaiTech University, 2F Building 6, 99 Haike Road, Pudong New District, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
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41
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Wu F, Zhang Y, Sun B, McMahon AP, Wang Y. Hedgehog Signaling: From Basic Biology to Cancer Therapy. Cell Chem Biol 2017; 24:252-280. [PMID: 28286127 DOI: 10.1016/j.chembiol.2017.02.010] [Citation(s) in RCA: 218] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/29/2016] [Accepted: 02/10/2017] [Indexed: 02/07/2023]
Abstract
The Hedgehog (HH) signaling pathway was discovered originally as a key pathway in embryonic patterning and development. Since its discovery, it has become increasingly clear that the HH pathway also plays important roles in a multitude of cancers. Therefore, HH signaling has emerged as a therapeutic target of interest for cancer therapy. In this review, we provide a brief overview of HH signaling and the key molecular players involved and offer an up-to-date summary of our current knowledge of endogenous and exogenous small molecules that modulate HH signaling. We discuss experiences and lessons learned from the decades-long efforts toward the development of cancer therapies targeting the HH pathway. Challenges to develop next-generation cancer therapies are highlighted.
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Affiliation(s)
- Fujia Wu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Bo Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Andrew P McMahon
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad-CIRM Center for Regenerative Medicine and Stem Cell Research, W.M. Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Yu Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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42
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Dash RC, Maschinot CR, Hadden MK. A molecular dynamics approach to identify an oxysterol-based hedgehog pathway inhibitor. Biochim Biophys Acta Gen Subj 2016; 1861:168-177. [PMID: 27825830 DOI: 10.1016/j.bbagen.2016.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/26/2016] [Accepted: 11/03/2016] [Indexed: 01/01/2023]
Abstract
BACKGROUND Multiple oxysterols (OHCs) have demonstrated the ability to act as agonists or antagonists of the hedgehog (Hh) signaling pathway, a developmental signaling pathway that has been implicated as a potential therapeutic target in a variety of human diseases. These OHCs are known to modulate Hh signaling through direct binding interactions with the N-terminal cysteine rich domain (CRD) of Smoothened, a key regulator of Hh signal transduction. METHODS Homology modeling, molecular dynamics simulations, and MM/GBSA energy calculations were utilized to explore binding interactions between the OHC scaffold and the human Smoothened CRD. Follow-up cellular assays explored the in vitro activity of potential Hh pathway modulators. RESULTS Structural features that govern key molecular interactions between the Smoothened CRD and the OHC scaffold were identified. Orientation of the iso-octyl side chain as well as the overall entropy of the OHC-CRD complex are important for determining activity against the Hh pathway. OHC 9, which was previously thought to be inactive because it was not an Hh agonist, was identified as an inhibitor of Hh signal transmission. CONCLUSIONS Calculated MM/GBSA binding energies for OHCs in complex with the CRD of Smoothened correlate well with in vitro Hh modulatory activity. Compounds with high affinity stabilize Smoothened and are antagonists, whereas compounds with reduced affinity allow a conformational change in Smoothened that results in pathway activation. GENERAL SIGNIFICANCE Computational modeling and molecular dynamics simulations can be used to predict whether a small molecule that binds the Smoothened CRD will be an agonist or antagonist of the pathway.
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Affiliation(s)
- Radha Charan Dash
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd., Unit 3092, Storrs, CT, 06269-3092, United States
| | - Chad R Maschinot
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd., Unit 3092, Storrs, CT, 06269-3092, United States
| | - M Kyle Hadden
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd., Unit 3092, Storrs, CT, 06269-3092, United States.
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43
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Byrne EF, Sircar R, Miller PS, Hedger G, Luchetti G, Nachtergaele S, Tully MD, Mydock-McGrane L, Covey DF, Rambo RP, Sansom MSP, Newstead S, Rohatgi R, Siebold C. Structural basis of Smoothened regulation by its extracellular domains. Nature 2016; 535:517-522. [PMID: 27437577 PMCID: PMC4970916 DOI: 10.1038/nature18934] [Citation(s) in RCA: 254] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 06/15/2016] [Indexed: 01/04/2023]
Abstract
Developmental signals of the Hedgehog (Hh) and Wnt families are transduced across the membrane by Frizzledclass G-protein-coupled receptors (GPCRs) composed of both a heptahelical transmembrane domain (TMD) and an extracellular cysteine-rich domain (CRD). How the large extracellular domains of GPCRs regulate signalling by the TMD is unknown. We present crystal structures of the Hh signal transducer and oncoprotein Smoothened, a GPCR that contains two distinct ligand-binding sites: one in its TMD and one in the CRD. The CRD is stacked a top the TMD, separated by an intervening wedge-like linker domain. Structure-guided mutations show that the interface between the CRD, linker domain and TMD stabilizes the inactive state of Smoothened. Unexpectedly, we find a cholesterol molecule bound to Smoothened in the CRD binding site. Mutations predicted to prevent cholesterol binding impair the ability of Smoothened to transmit native Hh signals. Binding of a clinically used antagonist, vismodegib, to the TMD induces a conformational change that is propagated to the CRD, resulting in loss of cholesterol from the CRD-linker domain-TMD interface. Our results clarify the structural mechanism by which the activity of a GPCR is controlled by ligand-regulated interactions between its extracellular and transmembrane domains.
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Affiliation(s)
- Eamon F.X. Byrne
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Ria Sircar
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Paul S. Miller
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - George Hedger
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Giovanni Luchetti
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Sigrid Nachtergaele
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Mark D. Tully
- Diamond Light Source Ltd, Harwell Science &Innovation Campus, Didcot, UK
| | - Laurel Mydock-McGrane
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Douglas F. Covey
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Robert P. Rambo
- Diamond Light Source Ltd, Harwell Science &Innovation Campus, Didcot, UK
| | | | - Simon Newstead
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Rajat Rohatgi
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Christian Siebold
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
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44
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Lucena-Agell D, Hervás-Aguilar A, Múnera-Huertas T, Pougovkina O, Rudnicka J, Galindo A, Tilburn J, Arst HN, Peñalva MA. Mutational analysis of the Aspergillus ambient pH receptor PalH underscores its potential as a target for antifungal compounds. Mol Microbiol 2016; 101:982-1002. [PMID: 27279148 PMCID: PMC5026065 DOI: 10.1111/mmi.13438] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/07/2016] [Indexed: 12/18/2022]
Abstract
The pal/RIM ambient pH signalling pathway is crucial for the ability of pathogenic fungi to infect hosts. The Aspergillus nidulans 7‐TMD receptor PalH senses alkaline pH, subsequently facilitating ubiquitination of the arrestin PalF. Ubiquitinated PalF triggers downstream signalling events. The mechanism(s) by which PalH transduces the alkaline pH signal to PalF is poorly understood. We show that PalH is phosphorylated in a signal dependent manner, resembling mammalian GPCRs, although PalH phosphorylation, in contrast to mammalian GPCRs, is arrestin dependent. A genetic screen revealed that an ambient‐exposed region comprising the extracellular loop connecting TM4‐TM5 and ambient‐proximal residues within TM5 is required for signalling. In contrast, substitution by alanines of four aromatic residues within TM6 and TM7 results in a weak ‘constitutive’ activation of the pathway. Our data support the hypothesis that PalH mechanistically resembles mammalian GPCRs that signal via arrestins, such that the relative positions of individual helices within the heptahelical bundle determines the Pro316‐dependent transition between inactive and active PalH conformations, governed by an ambient‐exposed region including critical Tyr259 that potentially represents an agonist binding site. These findings open the possibility of screening for agonist compounds stabilizing the inactive conformation of PalH, which might act as antifungal drugs against ascomycetes.
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Affiliation(s)
- Daniel Lucena-Agell
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - América Hervás-Aguilar
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Tatiana Múnera-Huertas
- Section of Microbiology, Imperial College London, Flowers Building, Armstrong Road, London, SW7 2AZ, UK
| | - Olga Pougovkina
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Joanna Rudnicka
- Section of Microbiology, Imperial College London, Flowers Building, Armstrong Road, London, SW7 2AZ, UK
| | - Antonio Galindo
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain
| | - Joan Tilburn
- Section of Microbiology, Imperial College London, Flowers Building, Armstrong Road, London, SW7 2AZ, UK
| | - Herbert N Arst
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain.,Section of Microbiology, Imperial College London, Flowers Building, Armstrong Road, London, SW7 2AZ, UK
| | - Miguel A Peñalva
- Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain.
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45
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Maschinot CA, Pace JR, Hadden MK. Synthetic Small Molecule Inhibitors of Hh Signaling As Anti-Cancer Chemotherapeutics. Curr Med Chem 2016; 22:4033-57. [PMID: 26310919 DOI: 10.2174/0929867322666150827093904] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 08/25/2015] [Accepted: 08/26/2015] [Indexed: 12/11/2022]
Abstract
The hedgehog (Hh) pathway is a developmental signaling pathway that is essential to the proper embryonic development of many vertebrate systems. Dysregulation of Hh signaling has been implicated as a causative factor in the development and progression of several forms of human cancer. As such, the development of small molecule inhibitors of Hh signaling as potential anti-cancer chemotherapeutics has been a major area of research interest in both academics and industry over the past ten years. Through these efforts, synthetic small molecules that target multiple components of the Hh pathway have been identified and advanced to preclinical or clinical development. The goal of this review is to provide an update on the current status of several synthetic small molecule Hh pathway inhibitors and explore the potential of several recently disclosed inhibitory scaffolds.
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Affiliation(s)
| | | | - M K Hadden
- Department of Pharmaceutical Sciences, University of Connecticut, 69 N Eagleville Rd, Unit 3092, Storrs, CT 06269-3092, USA.
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46
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Boulton S, Melacini G. Advances in NMR Methods To Map Allosteric Sites: From Models to Translation. Chem Rev 2016; 116:6267-304. [PMID: 27111288 DOI: 10.1021/acs.chemrev.5b00718] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The last five years have witnessed major developments in the understanding of the allosteric phenomenon, broadly defined as coupling between remote molecular sites. Such advances have been driven not only by new theoretical models and pharmacological applications of allostery, but also by progress in the experimental approaches designed to map allosteric sites and transitions. Among these techniques, NMR spectroscopy has played a major role given its unique near-atomic resolution and sensitivity to the dynamics that underlie allosteric couplings. Here, we highlight recent progress in the NMR methods tailored to investigate allostery with the goal of offering an overview of which NMR approaches are best suited for which allosterically relevant questions. The picture of the allosteric "NMR toolbox" is provided starting from one of the simplest models of allostery (i.e., the four-state thermodynamic cycle) and continuing to more complex multistate mechanisms. We also review how such an "NMR toolbox" has assisted the elucidation of the allosteric molecular basis for disease-related mutations and the discovery of novel leads for allosteric drugs. From this overview, it is clear that NMR plays a central role not only in experimentally validating transformative theories of allostery, but also in tapping the full translational potential of allosteric systems.
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Affiliation(s)
- Stephen Boulton
- Department of Chemistry and Chemical Biology Department of Biochemistry and Biomedical Sciences, McMaster University , 1280 Main St. W., Hamilton L8S 4M1, Canada
| | - Giuseppe Melacini
- Department of Chemistry and Chemical Biology Department of Biochemistry and Biomedical Sciences, McMaster University , 1280 Main St. W., Hamilton L8S 4M1, Canada
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47
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Fu L, Lv X, Xiong Y, Zhao Y. Investigation of Protein-Protein Interactions and Conformational Changes in Hedgehog Signaling Pathway by FRET. Methods Mol Biol 2016; 1322:61-70. [PMID: 26179039 DOI: 10.1007/978-1-4939-2772-2_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Protein-protein interactions and signal-induced protein conformational changes are fundamental molecular events that are considered as essential in modern life sciences. Among various techniques developed to study such phenomena, fluorescence resonance energy transfer (FRET) is a widely used method with many advantages in detecting these molecular events. Here, we describe the application of FRET in the mechanistic investigation of cell signal transduction, taking the example of the Hh signaling pathway, which plays a critical role in embryonic development and tissue homeostasis. A number of general guidelines as well as some key notes have been summarized as a protocol for reader's reference.
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Affiliation(s)
- Lin Fu
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institute of Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai, 200031, People's Republic of China
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48
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Jiang K, Liu Y, Fan J, Zhang J, Li XA, Evers BM, Zhu H, Jia J. PI(4)P Promotes Phosphorylation and Conformational Change of Smoothened through Interaction with Its C-terminal Tail. PLoS Biol 2016; 14:e1002375. [PMID: 26863604 PMCID: PMC4749301 DOI: 10.1371/journal.pbio.1002375] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/07/2016] [Indexed: 12/29/2022] Open
Abstract
In Hedgehog (Hh) signaling, binding of Hh to the Patched-Interference Hh (Ptc-Ihog) receptor complex relieves Ptc inhibition on Smoothened (Smo). A longstanding question is how Ptc inhibits Smo and how such inhibition is relieved by Hh stimulation. In this study, we found that Hh elevates production of phosphatidylinositol 4-phosphate (PI(4)P). Increased levels of PI(4)P promote, whereas decreased levels of PI(4)P inhibit, Hh signaling activity. We further found that PI(4)P directly binds Smo through an arginine motif, which then triggers Smo phosphorylation and activation. Moreover, we identified the pleckstrin homology (PH) domain of G protein-coupled receptor kinase 2 (Gprk2) as an essential component for enriching PI(4)P and facilitating Smo activation. PI(4)P also binds mouse Smo (mSmo) and promotes its phosphorylation and ciliary accumulation. Finally, Hh treatment increases the interaction between Smo and PI(4)P but decreases the interaction between Ptc and PI(4)P, indicating that, in addition to promoting PI(4)P production, Hh regulates the pool of PI(4)P associated with Ptc and Smo.
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Affiliation(s)
- Kai Jiang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - Yajuan Liu
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - Junkai Fan
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - Jie Zhang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - Xiang-An Li
- Department of Pediatrics, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - B. Mark Evers
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
- Department of Surgery, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - Haining Zhu
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
| | - Jianhang Jia
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America
- * E-mail:
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49
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Abstract
The Hedgehog (Hh) signaling pathway play critical roles in embryonic development and adult tissue homeostasis. A critical step in Hh signal transduction is how Hh receptor Patched (Ptc) inhibits the atypical G protein-coupled receptor Smoothened (Smo) in the absence of Hh and how this inhibition is release by Hh stimulation. It is unlikely that Ptc inhibits Smo by direct interaction. Here we discuss how Hh regulates the phosphorylation and ubiquitination of Smo, leading to cell surface and ciliary accumulation of Smo in Drosophila and vertebrate cells, respectively. In addition, we discuss how PI(4)P phospholipid acts in between Ptc and Smo to regulate Smo phosphorylation and activation in response to Hh stimulation.
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Affiliation(s)
- Kai Jiang
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jianhang Jia
- Markey Cancer Center, Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
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50
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Tena TC, Philipp M. Assessing Smoothened-mediated Hedgehog signaling in zebrafish. Methods Cell Biol 2015; 132:147-64. [PMID: 26928543 DOI: 10.1016/bs.mcb.2015.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Smoothened belongs to the class of atypical G protein-coupled receptors and serves as the transducing molecule in Hedgehog (Hh) signaling. Hh proteins comprise a family of secreted, cholesterol-modified ligands, which act both as morphogens and as signaling molecules. Binding of Hh proteins to their direct receptor, the transmembrane protein Patched-1, relieves Smoothened from tonal inhibition by Patched-1 and causes the translocation of Smoothened into the cilium. Here, the Hh signaling cascade is initiated and results in transcriptional activation of Hh target genes such as gli1 or patched-1. This induces a plethora of physiological outcomes including normal embryonic development, but also cancer, which is the reason why scientists aim to develop strategies to manipulate as well as monitor Smoothened-mediated Hh signaling. The zebrafish has emerged as a valuable tool for the assessment of Smoothened-mediated Hh signaling. In this chapter we thus describe how Smoothened-mediated Hh signaling can be monitored and also quantified using zebrafish embryos.
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Affiliation(s)
- Teresa Casar Tena
- Institute for Biochemistry and Molecular Biology, Ulm University, Ulm, Germany
| | - Melanie Philipp
- Institute for Biochemistry and Molecular Biology, Ulm University, Ulm, Germany
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