1
|
Kite J, Hill M, Preston N, Rubina A, Kollnberger S, Wang ECY, Elliott G. Downregulation of endogenous nectin1 in human keratinocytes by herpes simplex virus 1 glycoprotein D excludes superinfection but does not affect NK cell function. J Gen Virol 2024; 105:001969. [PMID: 38471041 PMCID: PMC10950026 DOI: 10.1099/jgv.0.001969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
Many viruses downregulate their cognate receptors, facilitating virus replication and pathogenesis via processes that are not yet fully understood. In the case of herpes simplex virus 1 (HSV1), the receptor binding protein glycoprotein D (gD) has been implicated in downregulation of its receptor nectin1, but current understanding of the process is limited. Some studies suggest that gD on the incoming virion is sufficient to achieve nectin1 downregulation, but the virus-encoded E3 ubiquitin ligase ICP0 has also been implicated. Here we have used the physiologically relevant nTERT human keratinocyte cell type - which we have previously shown to express readily detectable levels of endogenous nectin1 - to conduct a detailed investigation of nectin1 expression during HSV1 infection. In these cells, nectin1, but not nectin2 or the transferrin receptor, disappeared from the cell surface in a process that required virus protein synthesis rather than incoming virus, but did not involve virus-induced host shutoff. Furthermore, gD was not only required but was sufficient for nectin1 depletion, indicating that no other virus proteins are essential. NK cells were shown to be activated in the presence of keratinocytes, a process that was greatly inhibited in cells infected with wild-type virus. However, degranulation of NK cells was also inhibited in ΔgD-infected cells, indicating that blocking of NK cell activation was independent of gD downregulation of nectin1. By contrast, a superinfection time-course revealed that the ability of HSV1 infection to block subsequent infection of a GFP-expressing HSV1 was dependent on gD and occurred in line with the timing of nectin1 downregulation. Thus, the role of gD-dependent nectin1 impairment during HSV infection is important for virus infection, but not immune evasion, which is achieved by other mechanisms.
Collapse
Affiliation(s)
- Joanne Kite
- Section of Virology, Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford GU2 7XH, UK
| | - Monica Hill
- Section of Virology, Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford GU2 7XH, UK
| | - Natasha Preston
- Section of Virology, Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford GU2 7XH, UK
| | - Anzelika Rubina
- Division of Infection & Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
| | - Simon Kollnberger
- Division of Infection & Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
| | - Eddie Chung Yern Wang
- Division of Infection & Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK
| | - Gillian Elliott
- Section of Virology, Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford GU2 7XH, UK
| |
Collapse
|
2
|
Bone M, Inman GJ. Exon-specific oncogenic function of the long noncoding RNA plasmacytoma variant translocation 1 in cutaneous squamous cell carcinoma: a promising potential therapeutic target. Br J Dermatol 2024; 190:300-301. [PMID: 38037672 PMCID: PMC10873561 DOI: 10.1093/bjd/ljad476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Accepted: 12/08/2023] [Indexed: 12/02/2023]
Affiliation(s)
- Max Bone
- Cancer Research UK Scotland Institute and School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Gareth J Inman
- Cancer Research UK Scotland Institute and School of Cancer Sciences, University of Glasgow, Glasgow, UK
| |
Collapse
|
3
|
Goolamali SI, Shim TN, Purdie K, Mladkova N, Francis N, Harwood CA, Bunker CB. Is the presence of Merkel cell polyomavirus and human papillomavirus DNA in keratinocyte cancers and precancers associated with HIV status? A case-control study. Clin Exp Dermatol 2024; 49:263-266. [PMID: 37793080 DOI: 10.1093/ced/llad336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 09/24/2023] [Accepted: 09/26/2023] [Indexed: 10/06/2023]
Abstract
The epidemiology and potential pathogenic roles of human papillomavirus (HPV) and Merkel cell polyomavirus (MCV) in keratinocyte cancers (KCs) arising in people living with HIV (PLWH) compared with HIV-negative individuals are poorly understood. These issues were investigated by a case-control study in which the presence of MCV and HPV DNA was identified by polymerase chain reaction in microdissected formalin-fixed paraffin-embedded tissue from PLWH and HIV-negative individuals. The samples comprised 190 cutaneous and genital KCs/precancers (actinic keratoses, n = 43; cutaneous squamous cell carcinoma (cSCC) in situ, n = 24; basal cell carcinoma, n = 78; cSCC, n = 34; penile carcinoma in situ, n = 9; penile SCC, n = 2 from 104 individuals (PLWH, n = 51; HIV-negative, n = 53). Almost one-quarter of samples were positive for MCV: this was not significantly associated with either HIV status (P = 0.06) nor lesion type. Overall, 36% (16/44) of MCV-positive lesions were coinfected with HPV; this was also not associated with HIV status. These findings indicate that if these viruses do contribute to the pathogenesis of KCs, it is likely to be independent of HIV status.
Collapse
Affiliation(s)
- Sacha I Goolamali
- Dermatology Department, Chelsea and Westminster Hospital, London, UK
| | - Tang N Shim
- Dermatology Department, Chelsea and Westminster Hospital, London, UK
| | - Karin Purdie
- Blizard Institute, Queen Mary University of London, UK
| | | | | | | | - Christopher B Bunker
- Dermatology Department, Chelsea and Westminster Hospital, London, UK
- Dermatology Department, University College Hospital, London, UK
| |
Collapse
|
4
|
Petrasca A, Hambly R, Kearney N, Smith CM, Pender EK, Mac Mahon J, O'Rourke AM, Ismaiel M, Boland PA, Almeida JP, Kennedy C, Zaborowski A, Murphy S, Winter D, Kirby B, Fletcher JM. Metformin has anti-inflammatory effects and induces immunometabolic reprogramming via multiple mechanisms in hidradenitis suppurativa. Br J Dermatol 2023; 189:730-740. [PMID: 37648653 DOI: 10.1093/bjd/ljad305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/11/2023] [Accepted: 08/17/2023] [Indexed: 09/01/2023]
Abstract
BACKGROUND Targeting immunometabolism has shown promise in treating autoimmune and inflammatory conditions. Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease involving painful lesions in apocrine gland-bearing skin. Therapeutic options for HS are limited and often ineffective; thus, there is a pressing need for improved treatments. To date, metabolic dysregulation has not been investigated in HS. As HS is highly inflammatory, we hypothesized that energy metabolism is dysregulated in these patients. Metformin, an antidiabetic drug, which is known to impact on cellular metabolic and signalling pathways, has been shown to have anti-inflammatory effects in cancer and arthritis. While metformin is not licensed for use in HS, patients with HS taking metformin show improved clinical symptoms. OBJECTIVE To assess the effect and mechanism of action of metformin in HS. METHODS To assess the effect of metformin in vivo, we compared the immune and metabolic profiles of peripheral blood mononuclear cells (PBMCs) of patients with HS taking metformin vs. those not taking metformin. To examine the effect of metformin treatment ex vivo, we employed a skin explant model on skin biopsies from patients with HS not taking metformin, which we cultured with metformin overnight. We used enzyme-linked immunosorbent assays, multiplex cytokine assays and quantitative real-time polymerase chain reaction (RT-PCR) to measure inflammatory markers, and Seahorse flux technology and quantitative RT-PCR to assess glucose metabolism. RESULTS We showed that metabolic pathways are dysregulated in the PBMCs of patients with HS vs. healthy individuals. In metformin-treated patients, these metabolic pathways were restored and their PBMCs had reduced inflammatory markers following long-term metformin treatment. In the skin explant model, we found that overnight culture with metformin reduced inflammatory cytokines and chemokines and glycolytic genes in lesions and tracts of patients with HS. Using in vitro assays, we found that metformin may induce these changes via the NLR family pyrin domain containing 3 (NLRP3) inflammasome and the AMP-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR) pathway, which is linked to glycolysis and protein synthesis. CONCLUSIONS Our study provides insight into the mechanisms of action of metformin in HS. The anti-inflammatory effects of metformin support its use as a therapeutic agent in HS, while its effects on immunometabolism suggest that targeting metabolism is a promising therapeutic option in inflammatory diseases, including HS.
Collapse
Affiliation(s)
- Andreea Petrasca
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Roisin Hambly
- Department of Dermatology, St. Vincent's University Hospital, Dublin, Ireland
- Charles Institute of Dermatology, Dublin, Ireland
| | - Niamh Kearney
- Department of Dermatology, St. Vincent's University Hospital, Dublin, Ireland
- Charles Institute of Dermatology, Dublin, Ireland
| | - Conor M Smith
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Emily K Pender
- Department of Dermatology, St. Vincent's University Hospital, Dublin, Ireland
- Charles Institute of Dermatology, Dublin, Ireland
| | - Julie Mac Mahon
- Department of Dermatology, St. Vincent's University Hospital, Dublin, Ireland
- Charles Institute of Dermatology, Dublin, Ireland
| | - Aoife M O'Rourke
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Mohamed Ismaiel
- Department of Surgery, St. Michael's Hospital, Dublin, Ireland
| | | | - Jose P Almeida
- Department of Surgery, St. Michael's Hospital, Dublin, Ireland
| | - Czara Kennedy
- Department of Surgery, St. Michael's Hospital, Dublin, Ireland
| | | | - Siun Murphy
- Department of Plastic Reconstructive and Aesthetic Surgery, Blackrock Clinic, Dublin, Ireland
| | - Desmond Winter
- Department of Surgery, St. Michael's Hospital, Dublin, Ireland
| | - Brian Kirby
- Department of Dermatology, St. Vincent's University Hospital, Dublin, Ireland
- Charles Institute of Dermatology, Dublin, Ireland
| | - Jean M Fletcher
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
- School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| |
Collapse
|
5
|
Soo JK, Castle JT, Bennett DC. Preferential killing of melanoma cells by a p16-related peptide. Biol Open 2023; 12:bio059965. [PMID: 37522264 PMCID: PMC10445694 DOI: 10.1242/bio.059965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 07/25/2023] [Indexed: 08/01/2023] Open
Abstract
We report the identification of a synthetic, cell-penetrating peptide able to kill human melanoma cells efficiently and selectively, while being less toxic to normal human melanocytes and nontoxic to human fibroblasts. The peptide is based on the target-binding site of the melanoma suppressor and senescence effector p16 (also known as INK4A or CDKN2A), coupled to a cell-penetrating moiety. The killing is by apoptosis and appears to act by a route other than the canonical downstream target of p16 and CDK4, the retinoblastoma (RB) protein family, as it is also effective in HeLa cells and a melanocyte line expressing HPV E7 oncogenes, which both lack any active RB. There was varying toxicity to other types of cancer cell lines, such as glioblastoma. Melanoma cell killing by a p16-derived peptide was reported once before but only at a higher concentration, while selectivity and generality were not previously tested.
Collapse
Affiliation(s)
- Julia K. Soo
- Molecular & Clinical Sciences Research Institute, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Joanna T. Castle
- Molecular & Clinical Sciences Research Institute, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Dorothy C. Bennett
- Molecular & Clinical Sciences Research Institute, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| |
Collapse
|
6
|
Tagoe H, Hassan S, Bliss E, Youssef G, Heywood W, Mills K, Harper JI, O'Shaughnessy RFL. Chronic activation of Toll-like receptor 2 induces an ichthyotic skin phenotype. Br J Dermatol 2023; 189:91-102. [PMID: 36972303 DOI: 10.1093/bjd/ljad095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 03/06/2023] [Accepted: 03/18/2023] [Indexed: 03/29/2023]
Abstract
BACKGROUND Ichthyosis defines a group of chronic conditions that manifest phenotypically as a thick layer of scales, often affecting the entire skin. While the gene mutations that lead to ichthyosis are well documented, the actual signalling mechanisms that lead to scaling are poorly characterized; however, recent publications suggest that common mechanisms are active in ichthyotic tissue and in analogous models of ichthyosis. OBJECTIVES To determine common mechanisms of hyperkeratosis that may be easily targeted with small-molecule inhibitors. METHODS We combined gene expression analysis of gene-specific short hairpin RNA (shRNA) knockdowns in rat epidermal keratinocytes (REKs) of two genes mutated in autosomal recessive congenital ichthyosis (ARCI), Tgm1 and Alox12b, and proteomic analysis of skin scale from patients with ARCI, as well as RNA sequencing data from rat epidermal keratinocytes treated with the Toll-like receptor 2 (TLR2) agonist Pam3CSK4. RESULTS We identified common activation of the TLR2 pathway. Exogenous TLR2 activation led to increased expression of important cornified envelope genes and, in organotypic culture, caused hyperkeratosis. Conversely, blockade of TLR2 signalling in keratinocytes from patients with ichthyosis and our shRNA models reduced the expression of keratin 1, a structural protein overexpressed in ichthyosis scale. A time course of TLR2 activation in REKs revealed that although there was rapid initial activation of innate immune pathways, this was rapidly superseded by widespread upregulation of epidermal differentiation-related proteins. Both nuclear factor kappa B phosphorylation and GATA3 upregulation was associated with this switch, and GATA3 overexpression was sufficient to increase keratin 1 expression. CONCLUSIONS Taken together, these data define a dual role for TLR2 activation during epidermal barrier repair that may be a useful therapeutic modality in treating diseases of epidermal barrier dysfunction.
Collapse
Affiliation(s)
- Hephzi Tagoe
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
- Livingstone Skin Research Centre
| | - Sakinah Hassan
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
- Livingstone Skin Research Centre
| | | | - Gehad Youssef
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
- Livingstone Skin Research Centre
| | | | | | - John I Harper
- Livingstone Skin Research Centre
- Department of Immunobiology and Dermatology, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Ryan F L O'Shaughnessy
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
| |
Collapse
|
7
|
Scott H, Dong L, Stevenson A, MacDonald AI, Srinivasan S, Massimi P, Banks L, Martin PE, Johnstone SR, Graham SV. The human discs large protein 1 interacts with and maintains connexin 43 at the plasma membrane in keratinocytes. J Cell Sci 2023; 136:jcs259984. [PMID: 37288673 PMCID: PMC10309592 DOI: 10.1242/jcs.259984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/21/2023] [Indexed: 05/10/2023] Open
Abstract
Gap junction channels, composed of connexins, allow direct cell-to-cell communication. Connexin 43 (Cx43; also known as GJA1) is widely expressed in tissues, including the epidermis. In a previous study of human papillomavirus-positive cervical epithelial tumour cells, we identified Cx43 as a binding partner of the human homologue of Drosophila Discs large (Dlg1; also known as SAP97). Dlg1 is a member of the membrane associated-guanylate kinase (MAGUK) scaffolding protein family, which is known to control cell shape and polarity. Here, we show that Cx43 also interacts with Dlg1 in uninfected keratinocytes in vitro and in keratinocytes, dermal cells and adipocytes in normal human epidermis in vivo. Depletion of Dlg1 in keratinocytes did not alter Cx43 transcription but was associated with a reduction in Cx43 protein levels. Reduced Dlg1 levels in keratinocytes resulted in a reduction in Cx43 at the plasma membrane with a concomitant reduction in gap junctional intercellular communication and relocation of Cx43 to the Golgi compartment. Our data suggest a key role for Dlg1 in maintaining Cx43 at the plasma membrane in keratinocytes.
Collapse
Affiliation(s)
- Harry Scott
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Li Dong
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Andrew Stevenson
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Alasdair I. MacDonald
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| | - Sharmila Srinivasan
- Translation Research Platform for Veterinary Biologicals, Chennai, Tamil Nadu, India
| | - Paola Massimi
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Lawrence Banks
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Patricia E. Martin
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK
| | - Scott R. Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion, Center for Vascular and Heart Research, Virginia Tech, Roanoke VA 24016, USA
| | - Sheila V. Graham
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow G61 1QH, UK
| |
Collapse
|
8
|
Abstract
CYLD lysine 63 deubiquitinase (CYLD) is a ubiquitin hydrolase with important roles in immunity and cancer. Complete CYLD ablation, truncation and expression of alternate isoforms, including short CYLD, drive distinct phenotypes and offer insights into CYLD function in inflammation, cell death, cell cycle progression and cell transformation. Research in diverse model systems has shown that these are mediated via CYLD regulation of cellular pathways including the NF-κB, Wnt and TGF-β pathways. Recent biochemical advances and models have offered new insights into the regulation and function of CYLD. In addition, recent discoveries of gain-of-function germline pathogenic CYLD variants in patients with a neurodegenerative phenotype contrast with the more widely known loss-of-function mutations seen in patients with CYLD cutaneous syndrome and with sporadic cancers. Here, we provide a current review of mechanistic insights into CYLD function gained from CYLD animal models, as well as an update on the role of CYLD in human disease.
Collapse
Affiliation(s)
- José L Marín-Rubio
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Ishier Raote
- Université de Paris, CNRS, Institut Jacques Monod, Paris 75016, France
| | - Joseph Inns
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Carol Dobson-Stone
- Brain and Mind Centre and School of Medical Sciences, University of Sydney, Sydney, NSW 2050, Australia
| | - Neil Rajan
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
- Department of Dermatology, Royal Victoria Infirmary, Newcastle upon Tyne NE1 4LP, UK
| |
Collapse
|
9
|
Shelley JR, McHugh BJ, Wills J, Dorin JR, Weller R, Clarke DJ, Davidson DJ. A mechanistic evaluation of human beta defensin 2 mediated protection of human skin barrier in vitro. Sci Rep 2023; 13:2271. [PMID: 36755116 PMCID: PMC9908873 DOI: 10.1038/s41598-023-29558-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
The human skin barrier, a biological imperative, is impaired in inflammatory skin diseases such as atopic dermatitis (AD). Staphylococcus aureus is associated with AD lesions and contributes to pathological inflammation and further barrier impairment. S. aureus secretes extracellular proteases, such as V8 (or 'SspA'), which cleave extracellular proteins to reduce skin barrier. Previous studies demonstrated that the host defence peptide human beta-defensin 2 (HBD2) prevented V8-mediated damage. Here, the mechanism of HBD2-mediated barrier protection in vitro is examined. Application of exogenous HBD2 provided protection against V8, irrespective of timeline of application or native peptide folding, raising the prospect of simple peptide analogues as therapeutics. HBD2 treatment, in context of V8-mediated damage, modulated the proteomic/secretomic profiles of HaCaT cells, altering levels of specific extracellular matrix proteins, potentially recovering V8 damage. However, HBD2 alone did not substantially modulate cellular proteomic/secretomics profiles in the absence of damage, suggesting possible therapeutic targeting of lesion damage sites only. HBD2 did not show any direct protease inhibition or induce expression of known antiproteases, did not alter keratinocyte migration or proliferation, or form protective nanonet structures. These data validate the barrier-protective properties of HBD2 in vitro and establish key protein datasets for further targeted mechanistic analyses.
Collapse
Affiliation(s)
- Jennifer R Shelley
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, BioQuarter, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, Scotland, UK.
- The Commonwealth Building, The Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK.
| | - Brian J McHugh
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, BioQuarter, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, Scotland, UK
| | - Jimi Wills
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, The University of Edinburgh, Western General Hospital Campus, Crewe Road, Edinburgh, EH4 2XU, Scotland, UK
| | - Julia R Dorin
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, BioQuarter, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, Scotland, UK
| | - Richard Weller
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, BioQuarter, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, Scotland, UK
| | - David J Clarke
- The EastChem School of Chemistry, University of Edinburgh, Joseph Black Building, Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Donald J Davidson
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, BioQuarter, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, Scotland, UK
| |
Collapse
|
10
|
Bamford M, Udensi L, Khanna A, O'Riordan M, Saldanha G. Comparison of the prognostic value of microscopically measured invasive width versus macroscopic width in cutaneous melanoma shows the superiority of microscopic invasive width measurement. J Cutan Pathol 2022; 49:536-542. [PMID: 35262956 PMCID: PMC9314712 DOI: 10.1111/cup.14220] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/02/2022] [Accepted: 03/03/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Invasive width, the distance between the most peripheral invasive melanoma cells on the section where Breslow thickness (BT) was measured, was recently identified as a prognostic feature. It is unclear whether a routine measurement is justified, given that macroscopic width is already included in many melanoma histopathology reports and may itself be a prognostic feature. This study sought to investigate this. METHODS A retrospective cohort of 718 melanoma patients in which macroscopic width had been stated in the original histopathology report was used. Survival analysis was performed. RESULTS Macroscopic and invasive widths were positively correlated (p < 0.001). Invasive width was typically smaller than the paired macroscopic width (median difference 3.7 mm, p < 0.001), a difference seen across all T groups. Both macroscopic and invasive widths were significantly associated with melanoma survival in Kaplan-Meier analysis, including overall survival, but invasive width survival curves were more widely separated. Both were significantly associated with outcome after correction for BT in Cox proportional hazards regression, but the models containing invasive width had a substantially better fit. CONCLUSIONS This study shows that both macroscopic and invasive widths have prognostic values, but confirms that the latter is superior. It supports further investigation of this feature's prognostic value.
Collapse
Affiliation(s)
- Mark Bamford
- Department of Cellular PathologyUniversity Hospitals of Leicester NHS TrustLeicesterUK
| | - Louisa Udensi
- Department of Cellular PathologyUniversity Hospitals of Leicester NHS TrustLeicesterUK
| | - Arushi Khanna
- Leicester Medical SchoolUniversity of LeicesterLeicesterUK
| | - Marie O'Riordan
- Department of Cellular PathologyUniversity Hospitals of Leicester NHS TrustLeicesterUK
| | - Gerald Saldanha
- Department of Cellular PathologyUniversity Hospitals of Leicester NHS TrustLeicesterUK
- Leicester Cancer Research CentreUniversity of LeicesterLeicesterUK
| |
Collapse
|
11
|
Hurault G, Stalder JF, Mery S, Delarue A, Saint Aroman M, Josse G, Tanaka RJ. EczemaPred: A computational framework for personalised prediction of eczema severity dynamics. Clin Transl Allergy 2022; 12:e12140. [PMID: 35344305 PMCID: PMC8967258 DOI: 10.1002/clt2.12140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/12/2022] [Accepted: 03/14/2022] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Atopic dermatitis (AD) is a chronic inflammatory skin disease leading to substantial quality of life impairment with heterogeneous treatment responses. People with AD would benefit from personalised treatment strategies, whose design requires predicting how AD severity evolves for each individual. OBJECTIVE This study aims to develop a computational framework for personalised prediction of AD severity dynamics. METHODS We introduced EczemaPred, a computational framework to predict patient-dependent dynamic evolution of AD severity using Bayesian state-space models that describe latent dynamics of AD severity items and how they are measured. We used EczemaPred to predict the dynamic evolution of validated patient-oriented scoring atopic dermatitis (PO-SCORAD) by combining predictions from the models for the nine severity items of PO-SCORAD (six intensity signs, extent of eczema, and two subjective symptoms). We validated this approach using longitudinal data from two independent studies: a published clinical study in which PO-SCORAD was measured twice weekly for 347 AD patients over 17 weeks, and another one in which PO-SCORAD was recorded daily by 16 AD patients for 12 weeks. RESULTS EczemaPred achieved good performance for personalised predictions of PO-SCORAD and its severity items daily to weekly. EczemaPred outperformed standard time-series forecasting models such as a mixed effect autoregressive model. The uncertainty in predicting PO-SCORAD was mainly attributed to that in predicting intensity signs (75% of the overall uncertainty). CONCLUSIONS EczemaPred serves as a computational framework to make a personalised prediction of AD severity dynamics relevant to clinical practice. EczemaPred is available as an R package.
Collapse
|
12
|
Kite J, Russell T, Jones J, Elliott G. Cell-to-cell transmission of HSV1 in human keratinocytes in the absence of the major entry receptor, nectin1. PLoS Pathog 2021; 17:e1009631. [PMID: 34587223 PMCID: PMC8505007 DOI: 10.1371/journal.ppat.1009631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 10/11/2021] [Accepted: 09/16/2021] [Indexed: 11/23/2022] Open
Abstract
Herpes simplex virus 1 (HSV1) infects the stratified epithelia of the epidermis, oral or genital mucosa, where the main cell type is the keratinocyte. Here we have used nTERT human keratinocytes to generate a CRISPR-Cas9 knockout (KO) of the primary candidate HSV1 receptor, nectin1, resulting in a cell line that is refractory to HSV1 entry. Nonetheless, a small population of KO cells was able to support infection which was not blocked by a nectin1 antibody and hence was not a consequence of residual nectin1 expression. Strikingly at later times, the population of cells originally resistant to HSV1 infection had also become infected. Appearance of this later population was blocked by inhibition of virus genome replication, or infection with a ΔUL34 virus defective in capsid export to the cytoplasm. Moreover, newly formed GFP-tagged capsids were detected in cells surrounding the initial infected cell, suggesting that virus was spreading following replication in the original susceptible cells. Additional siRNA depletion of the second major HSV1 receptor HVEM, or PTP1B, a cellular factor shown elsewhere to be involved in cell-to-cell transmission, had no effect on virus spread in the absence of nectin1. Neutralizing human serum also failed to block virus transmission in nectin1 KO cells, which was dependent on the receptor binding protein glycoprotein D and the cell-to-cell spread glycoproteins gI and gE, indicating that virus was spreading by direct cell-to-cell transmission. In line with these results, both HSV1 and HSV2 formed plaques on nectin1 KO cells, albeit at a reduced titre, confirming that once the original cell population was infected, the virus could spread into all other cells in the monolayer. We conclude that although nectin1 is required for extracellular entry in to the majority of human keratinocytes, it is dispensable for direct cell-to-cell transmission. Herpes simplex virus 1 (HSV1) infects the epithelia of the epidermis, oral or genital mucosa to cause cold sores, genital herpes, or more serious outcomes such as keratitis and neonatal herpes. Like many viruses, HSV1 can spread through the extracellular environment or by direct cell-to-cell transmission, with the latter mechanism being important for avoiding antibody responses in the host. Here we have studied HSV1 entry and transmission in the human keratinocyte, the main cell type in the target epithelia, by generating a CRISPR-Cas9 knockout of the primary candidate virus receptor, nectin1. While HSV1 was unable to infect the majority of nectin1 knockout keratinocytes, a small population of these nectin1 KO cells remained susceptible to virus entry, and once infected, the virus was able to spread into the rest of the monolayer. This spread continued in the presence of neutralising serum which blocks extracellular virus, and required glycoprotein D, the main virus receptor-binding protein, and glycoproteins gE and gI which are known to be involved in cell-to-cell spread. Hence, while nectin1 is required for virus entry into the majority of human keratinocyte cells, it is dispensable for cell-to-cell transmission of the virus. These data have implications for the mechanism of HSV1 epithelial spread and pathogenesis.
Collapse
Affiliation(s)
- Joanne Kite
- Section of Virology, Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Tiffany Russell
- Section of Virology, Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Juliet Jones
- Section of Virology, Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Gillian Elliott
- Section of Virology, Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
- * E-mail:
| |
Collapse
|
13
|
Rabanal-Ruiz Y, Byron A, Wirth A, Madsen R, Sedlackova L, Hewitt G, Nelson G, Stingele J, Wills JC, Zhang T, Zeug A, Fässler R, Vanhaesebroeck B, Maddocks OD, Ponimaskin E, Carroll B, Korolchuk VI. mTORC1 activity is supported by spatial association with focal adhesions. J Cell Biol 2021; 220:e202004010. [PMID: 33635313 PMCID: PMC7923692 DOI: 10.1083/jcb.202004010] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 11/21/2020] [Accepted: 01/29/2021] [Indexed: 02/07/2023] Open
Abstract
The mammalian target of rapamycin complex 1 (mTORC1) integrates mitogenic and stress signals to control growth and metabolism. Activation of mTORC1 by amino acids and growth factors involves recruitment of the complex to the lysosomal membrane and is further supported by lysosome distribution to the cell periphery. Here, we show that translocation of lysosomes toward the cell periphery brings mTORC1 into proximity with focal adhesions (FAs). We demonstrate that FAs constitute discrete plasma membrane hubs mediating growth factor signaling and amino acid input into the cell. FAs, as well as the translocation of lysosome-bound mTORC1 to their vicinity, contribute to both peripheral and intracellular mTORC1 activity. Conversely, lysosomal distribution to the cell periphery is dispensable for the activation of mTORC1 constitutively targeted to FAs. This study advances our understanding of spatial mTORC1 regulation by demonstrating that the localization of mTORC1 to FAs is both necessary and sufficient for its activation by growth-promoting stimuli.
Collapse
Affiliation(s)
- Yoana Rabanal-Ruiz
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Adam Byron
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Alexander Wirth
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Ralitsa Madsen
- UCL Cancer Institute, University College London, London, UK
| | - Lucia Sedlackova
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Graeme Hewitt
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Glyn Nelson
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Julian Stingele
- Gene Center, Ludwig Maximilians University Munich, Munich, Germany
- Department of Biochemistry, Ludwig Maximilians University Munich, Munich, Germany
| | - Jimi C. Wills
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Tong Zhang
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - André Zeug
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Reinhard Fässler
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | | | - Oliver D.K. Maddocks
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Evgeni Ponimaskin
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
- Institute of Neuroscience, Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russia
| | | | - Viktor I. Korolchuk
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| |
Collapse
|
14
|
Adesanya EI, Schonmann Y, Hayes JF, Mathur R, Mulick AR, Rayner L, Smeeth L, Smith CH, Langan SM, Mansfield KE. Risk factors for mental illness in adults with atopic eczema or psoriasis: protocol for a systematic review. BMJ Open 2020; 10:e038324. [PMID: 33372068 PMCID: PMC7772326 DOI: 10.1136/bmjopen-2020-038324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Evidence indicates that people with the common inflammatory skin diseases atopic eczema or psoriasis are at increased risk of mental illness. However, the reasons for the relationship between skin disease and common mental disorders (ie, depression and anxiety) or severe mental illnesses (ie, schizophrenia, bipolar disorder and other psychoses) are unclear. Therefore, we aim to synthesise the available evidence regarding the risk factors for mental illness in adults with atopic eczema or psoriasis. METHODS AND ANALYSIS We will conduct a systematic review of randomised controlled trials, cohort, case-control and cross-sectional studies. We will search the following databases from inception to March 2020: Medline, Embase, Global Health, Scopus, the Cochrane Library, Web of Science, Base, PsycInfo, the Global Resource of Eczema Trials, and the grey literature databases Open Grey, PsycExtra and the New York Academy of Medicine Grey Literature Report. We will also search the bibliographies of eligible studies and relevant systematic reviews to identify additional relevant studies. Citation searching of large summary papers will be used to further identify relevant publications. Two reviewers will initially review study titles and abstracts for eligibility, followed by full text screening. We will extract data using a standardised data extraction form. We will assess the risk of bias of included studies using the Quality in Prognosis Studies tool. We will synthesise data narratively, and if studies are sufficiently homogenous, we will consider a meta-analysis. We will assess the quality of the evidence using the Grading of Recommendations, Assessment, Development and Evaluation framework. ETHICS AND DISSEMINATION Ethical approval is not required for a systematic review. Results of the review will be published in a peer-reviewed journal and disseminated through conferences. PROSPERO REGISTRATION NUMBER CRD42020163941.
Collapse
Affiliation(s)
- Elizabeth I Adesanya
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Yochai Schonmann
- Siaal Research Center for Family Medicine and Primary Care, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
- Department of Quality Measurements and Research, Clalit Health Services, Tel Aviv, Israel
| | - Joseph F Hayes
- Division of Psychiatry, University College London, London, UK
| | - Rohini Mathur
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Amy R Mulick
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Lauren Rayner
- Department of Psychological Medicine, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, UK
| | - Liam Smeeth
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Catherine H Smith
- St John's Institute of Dermatology, Guys and St Thomas' Foundation Trust and King's College London, London, UK
| | - Sinéad M Langan
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- Health Data Research UK, London, UK
| | - Kathryn E Mansfield
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| |
Collapse
|
15
|
Chen YL, Gomes T, Hardman CS, Vieira Braga FA, Gutowska-Owsiak D, Salimi M, Gray N, Duncan DA, Reynolds G, Johnson D, Salio M, Cerundolo V, Barlow JL, McKenzie AN, Teichmann SA, Haniffa M, Ogg G. Re-evaluation of human BDCA-2+ DC during acute sterile skin inflammation. J Exp Med 2020; 217:e20190811. [PMID: 31845972 PMCID: PMC7062525 DOI: 10.1084/jem.20190811] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 09/01/2019] [Accepted: 11/12/2019] [Indexed: 12/24/2022] Open
Abstract
Plasmacytoid dendritic cells (pDCs) produce type I interferon (IFN-I) and are traditionally defined as being BDCA-2+CD123+. pDCs are not readily detectable in healthy human skin, but have been suggested to accumulate in wounds. Here, we describe a CD1a-bearing BDCA-2+CD123int DC subset that rapidly infiltrates human skin wounds and comprises a major DC population. Using single-cell RNA sequencing, we show that these cells are largely activated DCs acquiring features compatible with lymph node homing and antigen presentation, but unexpectedly express both BDCA-2 and CD123, potentially mimicking pDCs. Furthermore, a third BDCA-2-expressing population, Axl+Siglec-6+ DCs (ASDC), was also found to infiltrate human skin during wounding. These data demonstrate early skin infiltration of a previously unrecognized CD123intBDCA-2+CD1a+ DC subset during acute sterile inflammation, and prompt a re-evaluation of previously ascribed pDC involvement in skin disease.
Collapse
Affiliation(s)
- Yi-Ling Chen
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Tomas Gomes
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - Clare S. Hardman
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Felipe A. Vieira Braga
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Open Targets, Wellcome Trust Genome Campus, Hinxton, UK
| | - Danuta Gutowska-Owsiak
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- University of Gdańsk, Intercollegiate Faculty of Biotechnology of University of Gdańsk and Medical University of Gdańsk, Gdańsk, Poland
| | - Maryam Salimi
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Nicki Gray
- Centre for Computational Biology, Weatherall Institute of Molecular Medicine, Oxford, UK
| | - David A. Duncan
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | | | - David Johnson
- Department of Plastic and Reconstructive Surgery, John Radcliffe Hospital, Oxford University Hospitals National Health Services Foundation Trust, Oxford, UK
| | - Mariolina Salio
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Vincenzo Cerundolo
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jillian L. Barlow
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Sarah A. Teichmann
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Theory of Condensed Matter, Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK
| | - Muzlifah Haniffa
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Institute of Cellular Medicine, Newcastle, UK
- Department of Dermatology and National Institute for Health Research Newcastle Biomedical Research Centre, Newcastle Hospitals National Health Services Foundation Trust, Newcastle upon Tyne, UK
| | - Graham Ogg
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
16
|
Carroll B, Nelson G, Rabanal-Ruiz Y, Kucheryavenko O, Dunhill-Turner NA, Chesterman CC, Zahari Q, Zhang T, Conduit SE, Mitchell CA, Maddocks ODK, Lovat P, von Zglinicki T, Korolchuk VI. Persistent mTORC1 signaling in cell senescence results from defects in amino acid and growth factor sensing. J Cell Biol 2017; 216:1949-1957. [PMID: 28566325 PMCID: PMC5496614 DOI: 10.1083/jcb.201610113] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 03/05/2017] [Accepted: 04/19/2017] [Indexed: 12/13/2022] Open
Abstract
Mammalian target of rapamycin complex 1 (mTORC1) and cell senescence are intimately linked to each other and to organismal aging. Inhibition of mTORC1 is the best-known intervention to extend lifespan, and recent evidence suggests that clearance of senescent cells can also improve health and lifespan. Enhanced mTORC1 activity drives characteristic phenotypes of senescence, although the underlying mechanisms responsible for increased activity are not well understood. We have identified that in human fibroblasts rendered senescent by stress, replicative exhaustion, or oncogene activation, mTORC1 is constitutively active and resistant to serum and amino acid starvation. This is driven in part by depolarization of senescent cell plasma membrane, which leads to primary cilia defects and a resultant failure to inhibit growth factor signaling. Further, increased autophagy and high levels of intracellular amino acids may act to support mTORC1 activity in starvation conditions. Interventions to correct these phenotypes restore sensitivity to the mTORC1 signaling pathway and cause death, indicating that persistent signaling supports senescent cell survival.
Collapse
Affiliation(s)
- Bernadette Carroll
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Glyn Nelson
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Yoana Rabanal-Ruiz
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Olena Kucheryavenko
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | | | - Charlotte C Chesterman
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Qabil Zahari
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Tong Zhang
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Sarah E Conduit
- Cancer Program, Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Christina A Mitchell
- Cancer Program, Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Oliver D K Maddocks
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Penny Lovat
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Thomas von Zglinicki
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Viktor I Korolchuk
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| |
Collapse
|
17
|
Carroll B, Maetzel D, Maddocks ODK, Otten G, Ratcliff M, Smith GR, Dunlop EA, Passos JF, Davies OR, Jaenisch R, Tee AR, Sarkar S, Korolchuk VI. Control of TSC2-Rheb signaling axis by arginine regulates mTORC1 activity. eLife 2016; 5:e11058. [PMID: 26742086 PMCID: PMC4764560 DOI: 10.7554/elife.11058] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 12/30/2015] [Indexed: 01/07/2023] Open
Abstract
The mammalian target of rapamycin complex 1 (mTORC1) is the key signaling hub that regulates cellular protein homeostasis, growth, and proliferation in health and disease. As a prerequisite for activation of mTORC1 by hormones and mitogens, there first has to be an available pool of intracellular amino acids. Arginine, an amino acid essential during mammalian embryogenesis and early development is one of the key activators of mTORC1. Herein, we demonstrate that arginine acts independently of its metabolism to allow maximal activation of mTORC1 by growth factors via a mechanism that does not involve regulation of mTORC1 localization to lysosomes. Instead, arginine specifically suppresses lysosomal localization of the TSC complex and interaction with its target small GTPase protein, Rheb. By interfering with TSC-Rheb complex, arginine relieves allosteric inhibition of Rheb by TSC. Arginine cooperates with growth factor signaling which further promotes dissociation of TSC2 from lysosomes and activation of mTORC1. Arginine is the main amino acid sensed by the mTORC1 pathway in several cell types including human embryonic stem cells (hESCs). Dependence on arginine is maintained once hESCs are differentiated to fibroblasts, neurons, and hepatocytes, highlighting the fundamental importance of arginine-sensing to mTORC1 signaling. Together, our data provide evidence that different growth promoting cues cooperate to a greater extent than previously recognized to achieve tight spatial and temporal regulation of mTORC1 signaling.
Collapse
Affiliation(s)
- Bernadette Carroll
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Dorothea Maetzel
- Whitehead Institute for Biomedical ResearchMassachusetts Institute of TechnologyCambridgeUnited States
| | | | - Gisela Otten
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Matthew Ratcliff
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Graham R Smith
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Elaine A Dunlop
- Institute of Cancer and GeneticsCardiff UniversityCardiffUnited Kingdom
| | - João F Passos
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Owen R Davies
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| | - Rudolf Jaenisch
- Whitehead Institute for Biomedical ResearchMassachusetts Institute of TechnologyCambridgeUnited States
| | - Andrew R Tee
- Institute of Cancer and GeneticsCardiff UniversityCardiffUnited Kingdom
| | - Sovan Sarkar
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Viktor I Korolchuk
- Institute for Cell and Molecular BiosciencesNewcastle UniversityNewcastle upon TyneUnited Kingdom
| |
Collapse
|