1
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Gurri S, Siegenthaler B, Cangkrama M, Restivo G, Huber M, Saliba J, Dummer R, Blank V, Hohl D, Werner S. NRF3 suppresses squamous carcinogenesis, involving the unfolded protein response regulator HSPA5. EMBO Mol Med 2023; 15:e17761. [PMID: 37807968 PMCID: PMC10630885 DOI: 10.15252/emmm.202317761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 09/05/2023] [Accepted: 09/15/2023] [Indexed: 10/10/2023] Open
Abstract
Epithelial skin cancers are extremely common, but the mechanisms underlying their malignant progression are still poorly defined. Here, we identify the NRF3 transcription factor as a tumor suppressor in the skin. NRF3 protein expression is strongly downregulated or even absent in invasively growing cancer cells of patients with basal and squamous cell carcinomas (BCC and SCC). NRF3 deficiency promoted malignant conversion of chemically induced skin tumors in immunocompetent mice, clonogenic growth and migration of human SCC cells, their invasiveness in 3D cultures, and xenograft tumor formation. Mechanistically, the tumor-suppressive effect of NRF3 involves HSPA5, a key regulator of the unfolded protein response, which we identified as a potential NRF3 interactor. HSPA5 levels increased in the absence of NRF3, thereby promoting cancer cell survival and migration. Pharmacological inhibition or knock-down of HSPA5 rescued the malignant features of NRF3-deficient SCC cells in vitro and in preclinical mouse models. Together with the strong expression of HSPA5 in NRF3-deficient cancer cells of SCC patients, these results suggest HSPA5 inhibition as a treatment strategy for these malignancies in stratified cancer patients.
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Affiliation(s)
- Selina Gurri
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Beat Siegenthaler
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Michael Cangkrama
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Gaetana Restivo
- Department of Dermatology, University Hospital Zurich, Zurich, Switzerland
| | - Marcel Huber
- Service of Dermatology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - James Saliba
- Lady Davis Institute for Medical Research, McGill University, Montreal, Canada
| | - Reinhard Dummer
- Department of Dermatology, University Hospital Zurich, Zurich, Switzerland
| | - Volker Blank
- Lady Davis Institute for Medical Research, McGill University, Montreal, Canada
| | - Daniel Hohl
- Service of Dermatology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Sabine Werner
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
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García-Galindo G, Castro J, Matés J, Bravo M, Ribó M, Vilanova M, Benito A. The Selectivity for Tumor Cells of Nuclear-Directed Cytotoxic RNases Is Mediated by the Nuclear/Cytoplasmic Distribution of p27 KIP1. Molecules 2021; 26:molecules26051319. [PMID: 33801209 PMCID: PMC7957890 DOI: 10.3390/molecules26051319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 02/24/2021] [Accepted: 02/25/2021] [Indexed: 12/03/2022] Open
Abstract
Although single targeted anti-cancer drugs are envisaged as safer treatments because they do not affect normal cells, cancer is a very complex disease to be eradicated with a single targeted drug. Alternatively, multi-targeted drugs may be more effective and the tumor cells may be less prone to develop drug resistance although these drugs may be less specific for cancer cells. We have previously developed a new strategy to endow human pancreatic ribonuclease with antitumor action by introducing in its sequence a non-classical nuclear localization signal. These engineered proteins cleave multiple species of nuclear RNA promoting apoptosis of tumor cells. Interestingly, these enzymes, on ovarian cancer cells, affect the expression of multiple genes implicated in metabolic and signaling pathways that are critic for the development of cancer. Since most of these targeted pathways are not highly relevant for non-proliferating cells, we envisioned the possibility that nuclear directed-ribonucleases were specific for tumor cells. Here, we show that these enzymes are much more cytotoxic for tumor cells in vitro. Although the mechanism of selectivity of NLSPE5 is not fully understood, herein we show that p27KIP1 displays an important role on the higher resistance of non-tumor cells to these ribonucleases.
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Affiliation(s)
- Glòria García-Galindo
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
| | - Jessica Castro
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
- Institut d’Investigació Biomèdica de Girona Josep Trueta (IdIBGi), 17003 Girona, Spain
| | - Jesús Matés
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
- Institut d’Investigació Biomèdica de Girona Josep Trueta (IdIBGi), 17003 Girona, Spain
| | - Marlon Bravo
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
- Institut d’Investigació Biomèdica de Girona Josep Trueta (IdIBGi), 17003 Girona, Spain
| | - Marc Ribó
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
- Institut d’Investigació Biomèdica de Girona Josep Trueta (IdIBGi), 17003 Girona, Spain
| | - Maria Vilanova
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
- Institut d’Investigació Biomèdica de Girona Josep Trueta (IdIBGi), 17003 Girona, Spain
- Correspondence: (M.V.); (A.B.); Tel.: +34-972418173 (M.V.); +34-630415072 (A.B.)
| | - Antoni Benito
- Laboratori d’Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Campus de Montilivi, Maria Aurèlia Capmany 40, 17003 Girona, Spain; (G.G.-G.); (J.C.); (J.M.); (M.B.); (M.R.)
- Institut d’Investigació Biomèdica de Girona Josep Trueta (IdIBGi), 17003 Girona, Spain
- Correspondence: (M.V.); (A.B.); Tel.: +34-972418173 (M.V.); +34-630415072 (A.B.)
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3
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van de Sandt J, Roguet R, Cohen C, Esdaile D, Ponec M, Corsini E, Barker C, Fusenig N, Liebsch M, Benford D, de Brugerolle de Fraissinette A, Fartasch M. The Use of Human Keratinocytes and Human Skin Models for Predicting Skin Irritation. Altern Lab Anim 2019; 27:723-43. [DOI: 10.1177/026119299902700504] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Johannes van de Sandt
- Toxicology Division, TNO Nutrition and Food Research Institute, Utrechtseweg 48, 3704 HE Zeist, The Netherlands
| | - Roland Roguet
- Life Sciences Research, L'Oréal Advanced Research, Central Department of Products Safety, 1 Avenue Eugene Schueller, 93600 Aulnay-sous-Bois, France
| | - Catherine Cohen
- Life Sciences Research, L'Oréal Advanced Research, Central Department of Products Safety, 1 Avenue Eugene Schueller, 93600 Aulnay-sous-Bois, France
| | - David Esdaile
- Rhône-Poulenc, BP 153, 355 Rue Dostoievski, 06903 Sophia Antipolis Cedex, France
| | - Maria Ponec
- Department of Dermatology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands
| | - Emanuela Corsini
- Istituto di Scienze Farmacologiche, Università degli Studi di Milano, Via Balzaretti 9, 20133 Milan, Italy
| | - Carol Barker
- School of Biomedical Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Norbert Fusenig
- Forschungsschwerpunkt Tumorzellregulation, Abteilung Differenzierung und Carcinogenese, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | | | - Diane Benford
- School of Biological Sciences, University of Surrey, Guildford, Surrey GU2 5XH, UK
| | | | - Manigé Fartasch
- Department of Dermatology, University of Erlangen, Hantmannstrasse 14, 91052 Erlangen, Germany
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4
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Nogueira AT, Braun KM, Carabeo RA. Characterization of the Growth of Chlamydia trachomatis in In Vitro-Generated Stratified Epithelium. Front Cell Infect Microbiol 2017; 7:438. [PMID: 29067282 PMCID: PMC5641298 DOI: 10.3389/fcimb.2017.00438] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 09/25/2017] [Indexed: 01/01/2023] Open
Abstract
Chlamydia infection targets the mucosal epithelium, where squamous and columnar epithelia can be found. Research on Chlamydia-epithelia interaction has predominantly focused on columnar epithelia, with very little known on how Chlamydia interacts with the squamous epithelium. The stratification and differentiation processes found in the squamous epithelium might influence chlamydial growth and infection dissemination. For this reason, three-dimensional (3D) organotypic stratified squamous epithelial cultures were adapted to mimic the stratified squamous epithelium and chlamydial infection was characterized. Chlamydia trachomatis infection in monolayers and 3D cultures were monitored by immunofluorescence and transmission electron microscopy to evaluate inclusion growth and chlamydial interconversion between elementary and reticulate body. We observed that the stratified epithelium varied in susceptibility to C. trachomatis serovars L2 and D infection. The undifferentiated basal cells were susceptible to infection by both serovars, while the terminally differentiated upper layers were resistant. The differentiating suprabasal cells exhibited different susceptibilities to serovars L2 and D, with the latter unable to establish a successful infection in this layer. Mature elementary body-containing inclusions were much more prevalent in these permissive basal layers, while the uppermost differentiated layers consistently harbored very few reticulate bodies with no elementary bodies, indicative of severely limited bacterial replication and development. For serovar D, the differentiation state of the host cell was a determining factor, as calcium-induced differentiation of cells in a monolayer negatively affected growth of this serovar, in contrast to serovar L2. The apparent completion of the developmental cycle in the basal layers of the 3D cultures correlated with the greater degree of dissemination within and the level of disruption of the stratified epithelium. Our studies indicate that the squamous epithelium is a suboptimal environment for growth, and thus potentially contributing to the protection of the lower genital tract from infection. The relatively more fastidious serovar D exhibited more limited growth than the faster-growing and more invasive L2 strain. However, if given access to the more hospitable basal cell layer, both strains were able to produce mature inclusions, replicate, and complete their developmental cycle.
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Affiliation(s)
- Ana T Nogueira
- Program in Microbiology, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom.,School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Kristin M Braun
- Centre for Cutaneous Research, Blizard Institute, Barts and the London School of Medicine and Dentistry, London, United Kingdom
| | - Rey A Carabeo
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
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5
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El Darzi E, Bazzi S, Daoud S, Echtay KS, Bahr GM. Differential regulation of surface receptor expression, proliferation, and apoptosis in HaCaT cells stimulated with interferon-γ, interleukin-4, tumor necrosis factor-α, or muramyl dipeptide. Int J Immunopathol Pharmacol 2017; 30:130-145. [PMID: 28449603 PMCID: PMC5806789 DOI: 10.1177/0394632017707611] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Keratinocytes are routinely subjected to both internal and external stimulation. This study investigates the effects of interferon gamma, interleukin-4, tumor necrosis factor alpha, and the synthetic immunomodulator muramyl dipeptide on the human keratinocyte cell line, HaCaT. Following HaCaT stimulation with cytokines or muramyl dipeptide for different time periods, changes in the expression of different cell surface receptors, cell proliferation, and cell apoptosis were evaluated by flow cytometry, tritiated thymidine uptake, and annexin-V staining, respectively. A significant decrease in the expression of CD49d was found upon treatment with interleukin-4. Interferon gamma and tumor necrosis factor alpha increased the expression of intercellular adhesion molecule 1 and major histocompatibility complex class I, whereas major histocompatibility complex class II and CD1b were only upregulated by interferon gamma. Interferon gamma and tumor necrosis factor alpha had opposite effects regarding CD119 expression, with the former downregulating, while the latter upregulating its expression. Of the stimuli tested, only interferon gamma and tumor necrosis factor alpha significantly inhibited proliferation of HaCaT cells, yet only interferon gamma played a significant role in inducing HaCaT cell apoptosis. Our data demonstrate differential effects of the three tested cytokines on keratinocytes and reveal that the absence of HaCaT cell responses to muramyl dipeptide is associated with undetectable levels of its cytoplasmic receptor, nucleotide-binding oligomerization domain-containing protein 2.
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Affiliation(s)
- Emale El Darzi
- 1 Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Al Kurah, Lebanon
| | - Samer Bazzi
- 2 Department of Biology, Faculty of Sciences, University of Balamand, Al Kurah, Lebanon
| | - Sarah Daoud
- 1 Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Al Kurah, Lebanon
| | - Karim S Echtay
- 1 Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Al Kurah, Lebanon
| | - Georges M Bahr
- 1 Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Al Kurah, Lebanon
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6
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Gursoy UK, Gursoy M, Könönen E, Sintim HO, Uitto VJ, Syrjänen S. Construction and characterization of a multilayered gingival keratinocyte culture model: the TURK-U model. Cytotechnology 2016; 68:2345-2354. [PMID: 27752840 DOI: 10.1007/s10616-016-0029-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 09/17/2016] [Indexed: 12/01/2022] Open
Abstract
In construction of epithelial cells as multilayers, the cells are grown submerged to confluence on fibroblast-embedded collagen gels and, then, lifted to air to promote their stratification. We recently demonstrated that gingival epithelial cells form uniform monolayers on semi-permeable nitrocellulose membranes, supported with a semi-solid growth medium, which allows the cells to grow at an air-liquid-solid interface from the beginning of the culturing protocol. In this study, the aim was to further develop our previous model to form a multilayered gingival epithelial culture model. Two different epithelial cell lines (HaCaT from skin and HMK from gingiva) were used in all experiments. Both cell lines were grown first as monolayers for 3 days. After that, keratinocytes were trypsinized, counted and seeded on a sterile semi-permeable nitrocellulose membrane placed on the top of a semi-solid growth medium, forming an air-liquid-solid interface for the cells to grow. At days 1, 4, and 7, epithelial cells were fixed, embedded in paraffin, and sectioned for routine Hematoxylin-Eosin staining and immunohistochemistry for cytokeratin (Ck). At day 1, HMK cells grew as monolayers, while HaCaT cells stratified forming an epithelium with two to three layers. At day 4, a stratified epithelium in the HMK model had four to five layers and its proliferation continued up to day 7. HaCaT cells formed a dense and weakly proliferating epithelium with three to four layers of stratification at day 4 but the proliferation disappeared at day 7. At all days, both models were strongly positive for Ck5, Ck7, and Ck 19, and weakly positive for Ck10. Gingival epithelial cells stratify successfully on semi-permeable nitrocellulose membranes, supported with a semi-solid growth medium. This technique allows researchers to construct uniform gingival epithelial cell multilayers at an air-liquid-solid interface, without using collagen gels, resulting in a more reproducible method.
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Affiliation(s)
- Ulvi K Gursoy
- Department of Periodontology, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520, Turku, Finland.
| | - Mervi Gursoy
- Department of Periodontology, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520, Turku, Finland
| | - Eija Könönen
- Department of Periodontology, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520, Turku, Finland.,Oral Health Care, Welfare Division, Turku, Finland
| | - Herman O Sintim
- Department of Chemistry and Purdue Institute for Drug Discovery and Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
| | - Veli-Jukka Uitto
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Stina Syrjänen
- Department of Oral Pathology, Institute of Dentistry, University of Turku, Turku, Finland
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7
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Prenzler F, Fragasso A, Schmitt A, Munz B. Functional analysis of ZFP36 proteins in keratinocytes. Eur J Cell Biol 2016; 95:277-84. [PMID: 27182009 DOI: 10.1016/j.ejcb.2016.04.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 04/28/2016] [Accepted: 04/28/2016] [Indexed: 12/22/2022] Open
Abstract
The ZFP36 family of zinc finger proteins, including ZFP36, ZFP36L1, and ZFP36L2, regulates the production of growth factors and cytokines via destabilization of the respective mRNAs. We could recently demonstrate that in cultured keratinocytes, expression of the ZFP36, ZFP36L1, and ZFP36L2 genes is induced by growth factors and cytokines and that ZFP36L1 is a potent regulator of keratinocyte VEGF production. We now further analyzed the localization and function of ZFP36 proteins in the skin, specifically in epidermal keratinocytes. We found that in human epidermis, the ZFP36 protein could be detected in basal and suprabasal keratinocytes, whereas ZFP36L1 and ZFP36L2 were expressed mainly in the basal layer, indicating different and non-redundant functions of the three proteins in the epidermis. Consistently, upon inhibition of ZFP36 or ZFP36L1 expression using specific siRNAs, there was no major effect on expression of the respective other gene. In addition, we demonstrate that both ZFP36 and ZFP36L1 influence keratinocyte cell cycle, differentiation, and apoptosis in a distinct manner. Finally, we show that similarly as ZFP36L1, ZFP36 is a potent regulator of keratinocyte VEGF production. Thus, it is likely that both proteins regulate angiogenesis via paracrine mechanisms. Taken together, our results suggest that ZFP36 proteins might control reepithelialization and angiogenesis in the skin in a multimodal manner.
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Affiliation(s)
- Frauke Prenzler
- University Hospital Tübingen, Medical Clinic, Department of Sports Medicine, Hoppe-Seyler-Str. 6, D-72076 Tübingen, Germany
| | - Annunziata Fragasso
- University Hospital Tübingen, Medical Clinic, Department of Sports Medicine, Hoppe-Seyler-Str. 6, D-72076 Tübingen, Germany
| | - Angelika Schmitt
- University Hospital Tübingen, Medical Clinic, Department of Sports Medicine, Hoppe-Seyler-Str. 6, D-72076 Tübingen, Germany
| | - Barbara Munz
- University Hospital Tübingen, Medical Clinic, Department of Sports Medicine, Hoppe-Seyler-Str. 6, D-72076 Tübingen, Germany.
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8
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Langbein L, Eckhart L, Fischer H, Rogers MA, Praetzel-Wunder S, Parry DAD, Kittstein W, Schweizer J. Localisation of keratin K78 in the basal layer and first suprabasal layers of stratified epithelia completes expression catalogue of type II keratins and provides new insights into sequential keratin expression. Cell Tissue Res 2015; 363:735-50. [PMID: 26340985 DOI: 10.1007/s00441-015-2278-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/07/2015] [Indexed: 01/21/2023]
Abstract
Among the 26 human type II keratins, K78 is the only one that has not yet been explored with regard to its expression characteristics. Here, we show that, at both the transcriptional and translational levels, K78 is strongly expressed in the basal and parabasal cell layers with decreasing intensity in the lower suprabasal cells of keratinising and non-keratinising squamous epithelia and keratinocyte cultures. The same pattern has been detected at the transcriptional level in the corresponding mouse epithelia. Murine K78 protein, which contains an extraordinary large extension of its tail domain, which is unique among all known keratins, is not detectable by the antibody used. Concomitant studies in human epithelia have confirmed K78 co-expression with the classical basal keratins K5 and K14. Similarly, K78 co-expression with the differentiation-related type I keratins K10 (epidermis) and K13 (non-keratinising epithelia) occurs in the parabasal cell layer, whereas that of the corresponding type II keratins K1 (epidermis) and K4 (non-keratinising epithelia) unequivocally starts subsequent to the respective type I keratins. Our data concerning K78 expression modify the classical concept of keratin pair K5/K14 representing the basal compartment and keratin pairs K1/K10 or K4/K13 defining the differentiating compartment of stratified epithelia. Moreover, the K78 expression pattern and the decoupled K1/K10 and K4/K13 expression define the existence of a hitherto unperceived early differentiation stage in the parabasal layer characterized by K78/K10 or K78/K13 expression.
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MESH Headings
- Adult
- Amino Acid Sequence
- Animals
- Carcinoma, Squamous Cell/metabolism
- Carcinoma, Squamous Cell/pathology
- Embryonic Development
- Epidermis/metabolism
- Epithelium/metabolism
- Evolution, Molecular
- Fluorescent Antibody Technique
- Gene Expression Regulation
- Genetic Loci
- Humans
- In Situ Hybridization
- Keratinocytes/metabolism
- Keratins, Type II/chemistry
- Keratins, Type II/genetics
- Keratins, Type II/metabolism
- Mice, Inbred C57BL
- Molecular Sequence Data
- Protein Transport
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Sequence Analysis, Protein
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Affiliation(s)
- Lutz Langbein
- Department of Genetics of Skin Carcinogenesis, German Cancer Research Center, A110, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.
| | - Leopold Eckhart
- Department of Dermatology, Medical University Vienna, Vienna, Austria
| | - Heinz Fischer
- Department of Dermatology, Medical University Vienna, Vienna, Austria
| | - Michael A Rogers
- Department of Molecular Genetics of the German Cancer Research Center, Heidelberg, Germany
| | - Silke Praetzel-Wunder
- Department of Genetics of Skin Carcinogenesis, German Cancer Research Center, A110, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - David A D Parry
- Institute of Fundamental Sciences and Riddet Institute, Massey University, Palmerston North, New Zealand
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9
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Zhang Y, Bai X, Wang Y, Li N, Li X, Han F, Su L, Hu D. Role for heat shock protein 90α in the proliferation and migration of HaCaT cells and in the deep second-degree burn wound healing in mice. PLoS One 2014; 9:e103723. [PMID: 25111496 PMCID: PMC4128658 DOI: 10.1371/journal.pone.0103723] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 07/01/2014] [Indexed: 01/22/2023] Open
Abstract
Inflammation, proliferation, and tissue remodeling are essential steps for wound healing. The hypoxic wound microenvironment promotes cell migration through a hypoxia—heat shock protein 90 alpha (Hsp90α)—low density lipoprotein receptor-related protein-1 (LRP-1) autocrine loop. To elucidate the role of this autocrine loop on burn wound healing, we investigated the expression profile of Hsp90α at the edge of burn wounds and found a transient increase in both mRNA and protein levels. Experiments performed with a human keratinocyte cell line—HaCaT also confirmed above results. 17-dimethylaminoethylamino-17demethoxygeldanamycin hydrochloride (17-DMAG), an Hsp90α inhibitor, was used to further evaluate the function of Hsp90α in wound healing. Consistently, topical application of Hsp90α in the early stage of deep second-degree burn wounds led to reduced inflammation and increased tissue granulation, with a concomitant reduction in the size of the wound at each time point tested (p<0.05). Consequently, epidermal cells at the wound margin progressed more rapidly causing an expedited healing process. In conclusion, these results provided a rationale for the therapeutic effect of Hsp90α on the burn wound management.
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Affiliation(s)
- Yue Zhang
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
| | - Xiaozhi Bai
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
| | - Yunchuan Wang
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
| | - Na Li
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
| | - Xiaoqiang Li
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
| | - Fei Han
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
| | - Linlin Su
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
- * E-mail: (LS); (DH)
| | - Dahai Hu
- Department of Burns and Cutaneous Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shannxi, China
- * E-mail: (LS); (DH)
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10
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Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity. PLoS One 2014; 9:e103125. [PMID: 25084357 PMCID: PMC4118848 DOI: 10.1371/journal.pone.0103125] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/25/2014] [Indexed: 12/20/2022] Open
Abstract
Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease), and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs). Recombinant SWAN protein (rSWAN) digested multiple forms of DNA including NET DNA and human RNA, which required both Mg2+ and Ca2+ for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.
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11
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Shen CI, Lee HC, Kao YH, Wu CS, Chen PH, Lin SZ, Lai PS, Su HL. EpCAM Induction Functionally Links to the Wnt-Enhanced Cell Proliferation in Human Keratinocytes. Cell Transplant 2014; 23:1031-1044. [PMID: 23635478 DOI: 10.3727/096368913x666403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Accelerating proliferation of primary keratinocytes benefits skin autografts for severely burned patients. Wnt signal, a conserved pathway controlling cell cycle and morphogenesis in embryo, also involves in cell proliferation and tumorigenesis in adult tissues. Here the effects of Wnt signal on the growth of human interfollicular keratinocytes were investigated. We demonstrated that recombinant Wnt3a significantly promoted the growth of primary keratinocytes at a low cell density. A well-characterized GSK-3b inhibitor, BIO, activated the Wnt signals and also enhanced the colony formation of keratinocytes dose dependently. Gene expression profile of the BIO-treated keratinocytes revealed the linkage of BIO with cell mitosis and indicated that epithelial cell adhesion molecule (EpCAM), a Wnt target gene, was significantly upregulated. Compared to the sorted EpCAM- keratinocytes, the EpCAM+ cells showed a higher proliferation rate and efficacy of colony formation. Inhibiting the EpCAM expression by shRNA attenuated the proliferation effect of BIO and the growth advantage of the EpCAM+ keratinocytes. These evidences emphasize the positive roles of canonical Wnt and EpCAM on the regulation of cell growth and self-renewal of human keratinocytes.
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Affiliation(s)
- Ching-I Shen
- Department of Chemistry, Agricultural Biotechnology Center, National Chung-Hsing University, Taiwan
| | - Hsiu-Chin Lee
- Department of Life Sciences, Agricultural Biotechnology Center, National Chung-Hsing University, Taiwan
| | - Ying-Hsien Kao
- Department of Medical Research, E-DA Hospital, I-Shou University, Taiwan
| | - Chieh-Shan Wu
- Department of Dermatology, Kaohsiung Veterans General Hospital, Taiwan
| | - Po-Hung Chen
- Chen Po-Hung Dermatologic Clinic, Kaohsiung, Taiwan
| | - Shinn-Zong Lin
- Center for Neuropsychiatry, China Medical University and Hospital, Taiwan.,China Medical University Beigang Hospital, Taiwan.,Department of Immunology, China Medical University, Taiwan
| | - Ping-Shan Lai
- Department of Chemistry, Agricultural Biotechnology Center, National Chung-Hsing University, Taiwan
| | - Hong-Lin Su
- Department of Life Sciences, Agricultural Biotechnology Center, National Chung-Hsing University, Taiwan.,Department of Physical Therapy, Graduate Institute of Rehabilitation Science, China Medical University, Taichung, Taiwan
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12
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Wound healing potential of a dimeric InlB variant analyzed by in vitro experiments on re-epithelialization of human skin models. Eur J Pharm Biopharm 2013; 86:277-83. [PMID: 24140590 DOI: 10.1016/j.ejpb.2013.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 10/04/2013] [Accepted: 10/07/2013] [Indexed: 12/11/2022]
Abstract
A constitutively dimeric truncated variant of internalin B (InlB321-CD), acting as stimulator of the receptor tyrosine kinase MET, was tested for dermal wound-healing potential. Due to a lack of the endogenous MET agonist HGF/SF in chronic wounds, HGF/SF substitution by an InlB321-CD-loaded hydrogel might be beneficial in chronic wound therapy. In this study, InlB321-CD in solution and incorporated in a hydrogel was tested for mitogenic effects on immortalized human dermal keratinocytes (HaCaT) with an MTT assay. Cell migration was investigated with a scratch assay on primary keratinocytes (PHK) and on HaCaT. For the latter, scratching needed to be mitomycin C-controlled. InlB321-CD effects on a model of human skin were analyzed histologically with respect to viability. InlB321-CD led to dose-dependent proliferative effects on HaCaT cells whereas the equimolar dose of monomeric InlB321 did not. Upon hydrogel incorporation of InlB321-CD its mitogenic activity for HaCaT cells was maintained thus confirming the hydrogel as a promising drug delivery system. Motogenic effects were shown on both HaCaT and PHK cells. InlB321-CD neither possesses cytotoxic effects on the viability of a human skin model nor alters its organotypic cell morphology.
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13
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Seo MD, Kang TJ, Lee CH, Lee AY, Noh M. HaCaT Keratinocytes and Primary Epidermal Keratinocytes Have Different Transcriptional Profiles of Cornified Envelope-Associated Genes to T Helper Cell Cytokines. Biomol Ther (Seoul) 2013; 20:171-6. [PMID: 24116291 PMCID: PMC3792214 DOI: 10.4062/biomolther.2012.20.2.171] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 03/04/2012] [Accepted: 03/06/2012] [Indexed: 02/04/2023] Open
Abstract
HaCaT cells are the immortalized human keratinocytes and have been extensively used to study the epidermal homeostasis and its pathophysiology. T helper cells play a role in various chronic dermatological conditions and they can affect skin barrier homeostasis. To evaluate whether HaCaT cells can be used as a model cell system to study abnormal skin barrier development in various dermatologic diseases, we analyzed the gene expression profile of epidermal differentiation markers of HaCaT cells in response to major T helper (Th) cell cytokines, such as IFNγ, IL-4, IL-17A and IL-22. The gene transcriptional profile of cornified envelope-associated proteins, such as filaggrin, loricrin, involucrin and keratin 10 (KRT10), in HaCaT cells was generally different from that in normal human keratinocytes (NHKs). This suggests that HaCaT cells have a limitation as a model system to study the pathophysiological mechanism associated with the Th cell cytokine-dependent changes in cornified envelope-associated proteins which are essential for normal skin barrier development. In contrast, the gene transcription profile change of human β2-defensin (HBD2) in response to IFNγ, IL-4 or IL-17A in HaCaT cells was consistent with the expression pattern of NHKs. IFNγ also up-regulated transglutaminase 2 (TGM2) gene transcription in both HaCaT cells and NHKs. As an alternative cell culture system for NHKs, HaCaT cells can be used to study molecular mechanisms associated with abnormal HBD2 and TGM2 expression in response to IFNγ, IL-4 or IL-17A.
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Affiliation(s)
- Min-Duk Seo
- College of Pharmacy, Ajou University, Suwon 443-749
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14
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Bose A, Teh MT, Mackenzie IC, Waseem A. Keratin k15 as a biomarker of epidermal stem cells. Int J Mol Sci 2013; 14:19385-98. [PMID: 24071939 PMCID: PMC3821562 DOI: 10.3390/ijms141019385] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 09/05/2013] [Accepted: 09/10/2013] [Indexed: 01/21/2023] Open
Abstract
Keratin 15 (K15) is type I keratin protein co-expressed with the K5/K14 pair present in the basal keratinocytes of all stratified epithelia. Although it is a minor component of the cytoskeleton with a variable expression pattern, nonetheless its expression has been reported as a stem cell marker in the bulge of hair follicles. Conversely, suprabasal expression of K15 has also been reported in both normal and diseased tissues, which is inconsistent with its role as a stem cell marker. Our recently published work has given evidence of the molecular pathways that seem to control the expression of K15 in undifferentiated and differentiated cells. In this article, we have critically reviewed the published work to establish the reliability of K15 as an epidermal stem cell marker.
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Affiliation(s)
- Amrita Bose
- Centre for Clinical and Diagnostic Oral Sciences, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK.
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15
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Breitkreutz D, Koxholt I, Thiemann K, Nischt R. Skin basement membrane: the foundation of epidermal integrity--BM functions and diverse roles of bridging molecules nidogen and perlecan. BIOMED RESEARCH INTERNATIONAL 2013; 2013:179784. [PMID: 23586018 PMCID: PMC3618921 DOI: 10.1155/2013/179784] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 01/18/2013] [Accepted: 01/28/2013] [Indexed: 02/06/2023]
Abstract
The epidermis functions in skin as first defense line or barrier against environmental impacts, resting on extracellular matrix (ECM) of the dermis underneath. Both compartments are connected by the basement membrane (BM), composed of a set of distinct glycoproteins and proteoglycans. Herein we are reviewing molecular aspects of BM structure, composition, and function regarding not only (i) the dermoepidermal interface but also (ii) the resident microvasculature, primarily focusing on the per se nonscaffold forming components perlecan and nidogen-1 and nidogen-2. Depletion or functional deficiencies of any BM component are lethal at some stage of development or around birth, though BM defects vary between organs and tissues. Lethality problems were overcome by developmental stage- and skin-specific gene targeting or by cell grafting and organotypic (3D) cocultures of normal or defective cells, which allows recapitulating BM formation de novo. Thus, evidence is accumulating that BM assembly and turnover rely on mechanical properties and composition of the adjacent ECM and the dynamics of molecular assembly, including further "minor" local components, nidogens largely functioning as catalysts or molecular adaptors and perlecan as bridging stabilizer. Collectively, orchestration of BM assembly, remodeling, and the role of individual players herein are determined by the developmental, tissue-specific, or functional context.
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Affiliation(s)
- Dirk Breitkreutz
- Department of Dermatology, University of Cologne, Kerpener Strasse 62, 50937 Cologne, Germany.
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16
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Okugawa Y, Hirai Y. Extracellular epimorphin modulates epidermal differentiation signals mediated by epidermal growth factor receptor. J Dermatol Sci 2013; 69:236-42. [DOI: 10.1016/j.jdermsci.2012.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 11/04/2012] [Accepted: 11/06/2012] [Indexed: 11/29/2022]
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17
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Ramot Y, Sugawara K, Zákány N, Tóth BI, Bíró T, Paus R. A novel control of human keratin expression: cannabinoid receptor 1-mediated signaling down-regulates the expression of keratins K6 and K16 in human keratinocytes in vitro and in situ. PeerJ 2013; 1:e40. [PMID: 23638377 PMCID: PMC3628749 DOI: 10.7717/peerj.40] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 01/28/2013] [Indexed: 12/23/2022] Open
Abstract
Cannabinoid receptors (CB) are expressed throughout human skin epithelium. CB1 activation inhibits human hair growth and decreases proliferation of epidermal keratinocytes. Since psoriasis is a chronic hyperproliferative, inflammatory skin disease, it is conceivable that the therapeutic modulation of CB signaling, which can inhibit both proliferation and inflammation, could win a place in future psoriasis management. Given that psoriasis is characterized by up-regulation of keratins K6 and K16, we have investigated whether CB1 stimulation modulates their expression in human epidermis. Treatment of organ-cultured human skin with the CB1-specific agonist, arachidonoyl-chloro-ethanolamide (ACEA), decreased K6 and K16 staining intensity in situ. At the gene and protein levels, ACEA also decreased K6 expression of cultured HaCaT keratinocytes, which show some similarities to psoriatic keratinocytes. These effects were partly antagonized by the CB1-specific antagonist, AM251. While CB1-mediated signaling also significantly inhibited human epidermal keratinocyte proliferation in situ, as shown by K6/Ki-67-double immunofluorescence, the inhibitory effect of ACEA on K6 expression in situ was independent of its anti-proliferative effect. Given recent appreciation of the role of K6 as a functionally important protein that regulates epithelial wound healing in mice, it is conceivable that the novel CB1-mediated regulation of keratin 6/16 revealed here also is relevant to wound healing. Taken together, our results suggest that cannabinoids and their receptors constitute a novel, clinically relevant control element of human K6 and K16 expression.
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Affiliation(s)
- Yuval Ramot
- Department of Dermatology, University of Luebeck, Luebeck, Germany.,Department of Dermatology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Koji Sugawara
- Department of Dermatology, University of Luebeck, Luebeck, Germany.,Department of Dermatology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Nóra Zákány
- Department of Dermatology, University of Luebeck, Luebeck, Germany.,DE-MTA "Lendület" Cellular Physiology Research Group, Department of Physiology, MHSC, RCMM, University of Debrecen, Debrecen, Hungary
| | - Balázs I Tóth
- DE-MTA "Lendület" Cellular Physiology Research Group, Department of Physiology, MHSC, RCMM, University of Debrecen, Debrecen, Hungary.,Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Tamás Bíró
- DE-MTA "Lendület" Cellular Physiology Research Group, Department of Physiology, MHSC, RCMM, University of Debrecen, Debrecen, Hungary
| | - Ralf Paus
- Department of Dermatology, University of Luebeck, Luebeck, Germany.,Institute of Inflammation and Repair, and Dermatology Centre, University of Manchester, Manchester, UK
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18
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A potential skin substitute constructed with hEGF gene modified HaCaT cells for treatment of burn wounds in a rat model. Burns 2012; 38:702-12. [DOI: 10.1016/j.burns.2011.12.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Revised: 12/13/2011] [Accepted: 12/15/2011] [Indexed: 12/28/2022]
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19
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Bose A, Teh MT, Hutchison IL, Wan H, Leigh IM, Waseem A. Two mechanisms regulate keratin K15 expression in keratinocytes: role of PKC/AP-1 and FOXM1 mediated signalling. PLoS One 2012; 7:e38599. [PMID: 22761689 PMCID: PMC3384677 DOI: 10.1371/journal.pone.0038599] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 05/08/2012] [Indexed: 01/24/2023] Open
Abstract
Background Keratin 15 (K15) is a type I keratin that is used as a marker of stem cells. Its expression is restricted to the basal layer of stratified epithelia, and the bulge in hair follicles. However, in certain clinical situations including oral lichen planus, K15 is induced in suprabasal layers, which is inconsistent with the role of a stem cell marker. This study provides insights into the mechanisms of K15 expression in the basal and differentiating keratinocytes. Methodology/Principal Findings Human keratinocytes were differentiated by three different methods; suspension in methylcellulose, high cell density and treatment with phorbol ester. The expression of mRNA was determined by quantitative PCR and protein by western blotting and immunostaining. Keratinocytes in suspension suppressed β1-integrin expression, induced differentiation-specific markers and K15, whereas FOXM1 (a cell cycle regulated protein) and K14 were downregulated. Rescuing β1-integrin by either fibronectin or the arginine-glycine-aspartate peptide suppressed K15 but induced K14 and FOXM1 expression. Specific inhibition of PKCδ, by siRNA, and AP-1 transcription factor, by TAM67 (dominant negative c-Jun), suppressed K15 expression, suggesting that PKC/AP-1 pathway plays a role in the differentiation-specific expression of K15. The basal cell-specific K15 expression may involve FOXM1 because ectopic expression of the latter is known to induce K15. Using chromatin immunoprecipitation, we have identified a single FOXM1 binding motif in the K15 promoter. Conclusions/Significance The data suggests that K15 is induced during terminal differentiation mediated by the down regulation of β1-integrin. However, this cannot be the mechanism of basal/stem cell-specific K15 expression in stratified epithelia, because basal keratinocytes do not undergo terminal differentiation. We propose that there are two mechanisms regulating K15 expression in stratified epithelia; differentiation-specific involving PKC/AP-1 pathway, and basal-specific mediated by FOXM1, and therefore the use of K15 expression as a marker of stem cells must be viewed with caution.
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Affiliation(s)
- Amrita Bose
- Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Muy-Teck Teh
- Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Iain L. Hutchison
- Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Hong Wan
- Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Irene M. Leigh
- Division of Cancer, Medical Research Institute, University of Dundee, Dundee, United Kingdom
| | - Ahmad Waseem
- Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
- * E-mail:
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20
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Cholesteatoma-associated fibroblasts modulate epithelial growth and differentiation through KGF/FGF7 secretion. Histochem Cell Biol 2012; 138:251-69. [PMID: 22481617 PMCID: PMC3407559 DOI: 10.1007/s00418-012-0947-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2012] [Indexed: 11/04/2022]
Abstract
The keratinocyte growth factor (KGF/FGF7), produced by stromal cells, is a key paracrine mediator of epithelial proliferation, differentiation and migration. Expression of the growth factor is increased in wound healing and in hyperproliferative epithelial diseases, as a consequence of the activation of dermal fibroblasts by the inflammatory microenvironment. The middle ear cholesteatoma, an aural epidermal pathology characterized by keratinocyte hyperproliferation and chronic inflammation, may represent a model condition to study the epithelial-mesenchymal interactions. To develop an in vitro model for this disease, we isolated and characterized human primary cultures of fibroblasts associated with the cholesteatoma lesion, analyzing their secretory behaviour and degree of differentiation or activation. Compared to the perilesional or control normal fibroblasts, all cultures derived from cholesteatoma tissues were less proliferating and more differentiated and their highly variable activated phenotype correlated with the secretion of KGF as well as of metalloproteases 2 and 9. Culture supernatants collected from the cholesteatoma-associated fibroblasts were able to increase the proliferation and differentiation of human keratinocytes assessed by the expression of Ki67 and keratin-1 markers. The single crucial contribution of the KGF released by fibroblasts on the keratinocyte biological response was shown by the specific, although partial, block induced by inhibiting the KGF receptor or by immunoneutralizing the growth factor. Altogether, these results suggest that the activation of the stromal fibroblasts present in the pathological tissue, and the consequent increased secretion of KGF, play a crucial role in the deregulation of the epidermal proliferation and differentiation.
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21
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Hacker C, Valchanova R, Adams S, Munz B. ZFP36L1 is regulated by growth factors and cytokines in keratinocytes and influences their VEGF production. Growth Factors 2010; 28:178-90. [PMID: 20166898 DOI: 10.3109/08977190903578660] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Keratinocyte-derived growth factors and cytokines play an important role in epidermal homeostasis and particularly in cutaneous wound repair. Thus, we analyzed a potential role of the ZFP36/tristetraprolin family of zinc finger proteins, which are targets of these factors, but also regulate their production, in keratinocytes. We show that expression of ZFP36, ZFP36L1, and ZFP36L2 is induced by a broad variety of growth factors and cytokines, and by scratch wounding. Since ZFP36L1 is a modulator of vascular endothelium growth factor (VEGF) mRNA stability, we subsequently used siRNA technology to inhibit ZFP36L1 gene expression. Notably, this treatment resulted in prolonged maintenance of elevated VEGF levels in HaCaT keratinocytes upon epidermal growth factor stimulation of these cells. Taken together, our results suggest an important role of ZFP36L1 in wound healing.
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Affiliation(s)
- Christine Hacker
- Institute of Physiology, Charité - University Medicine Berlin, Arnimallee 22, D-14195, Berlin, Germany
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22
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Sedimentation field-flow fractionation separation of proliferative and differentiated subpopulations during Ca2+-induced differentiation in HaCaT cells. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:1051-8. [DOI: 10.1016/j.jchromb.2010.03.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 03/05/2010] [Accepted: 03/09/2010] [Indexed: 11/22/2022]
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23
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Alternative splicing of human papillomavirus type-16 E6/E6* early mRNA is coupled to EGF signaling via Erk1/2 activation. Proc Natl Acad Sci U S A 2010; 107:7006-11. [PMID: 20351270 DOI: 10.1073/pnas.1002620107] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Certain types of human papillomaviruses (HPVs) are etiologically linked to cervical cancer. Their transforming capacity is encoded by a polycistronic premRNA, where alternative splicing leads to the translation of functional distinct proteins such as E6, E6*, and E7. Here we show that splicing of HPV16 E6/E7 ORF cassette is regulated by the epidermal growth factor (EGF) pathway. The presence of EGF was coupled to preferential E6 expression, whereas depletion of EGF, or treatment with EGF receptor (EGFR) neutralizing antibodies or the EGFR inhibitor tyrphostin AG1478, resulted in E6 exon exclusion in favor of E6*. As a consequence, increased p53 levels and enhanced translation of E7 with a subsequent reduction of the retinoblastoma protein pRb could be discerned. E6 exon exclusion upon EGF depletion was independent from promoter usage, mRNA stability, or selective mRNA transport. Time-course experiments and incubation with cycloheximide demonstrated that E6 alternative splicing is a direct and reversible effect of EGF signal transduction, not depending on de novo protein synthesis. Within this process, Erk1/2-kinase activation was the critical event for E6 exon inclusion, mediated by the upstream MAP kinase MEK1/2. Moreover, siRNA knockdown experiments revealed an involvement of splicing factors hnRNPA1 and hnRNPA2 in E6 exon exclusion, whereas the splicing factors Brm and Sam68 were found to promote E6 exon inclusion. Because there is a natural gradient of EGF and EGF receptor expression in the stratified epithelium, it is reasonable to assume that EGF modulates E6/E7 splicing during the viral life cycle and transformation.
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24
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Adams S, Valchanova RS, Munz B. RIP2: A novel player in the regulation of keratinocyte proliferation and cutaneous wound repair? Exp Cell Res 2010; 316:728-36. [DOI: 10.1016/j.yexcr.2009.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Revised: 12/01/2009] [Accepted: 12/01/2009] [Indexed: 12/25/2022]
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25
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Platelet activating factor stimulates arachidonic acid release in differentiated keratinocytes via arachidonyl non-selective phospholipase A2. Arch Dermatol Res 2009; 302:221-7. [PMID: 20041255 PMCID: PMC2829133 DOI: 10.1007/s00403-009-1017-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 12/10/2009] [Accepted: 12/14/2009] [Indexed: 11/27/2022]
Abstract
Platelet activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is known to be present in excess in psoriatic skin, but its exact role is uncertain. In the present study we demonstrate for the first time the role of group VI PLA2 in PAF-induced arachidonic acid release in highly differentiated human keratinocytes. The group IVα PLA2 also participates in the release, while secretory PLA2s play a minor role. Two anti-inflammatory synthetic fatty acids, tetradecylthioacetic acid and tetradecylselenoacetic acid, are shown to interfere with signalling events upstream of group IVα PLA2 activation. In summary, our major novel finding is the involvement of the arachidonyl non-selective group VI PLA2 in PAF-induced inflammatory responses.
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26
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Mielgo A, Torres VA, Schmid MC, Graf R, Zeitlin SG, Lee P, Shields DJ, Barbero S, Jamora C, Stupack DG. The death effector domains of caspase-8 induce terminal differentiation. PLoS One 2009; 4:e7879. [PMID: 19924290 PMCID: PMC2774162 DOI: 10.1371/journal.pone.0007879] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Accepted: 10/15/2009] [Indexed: 11/19/2022] Open
Abstract
The differentiation and senescence programs of metazoans play key roles in regulating normal development and preventing aberrant cell proliferation, such as cancer. These programs are intimately associated with both the mitotic and apoptotic pathways. Caspase-8 is an apical apoptotic initiator that has recently been appreciated to coordinate non-apoptotic roles in the cell. Most of these functions are attributed to the catalytic domain, however, the amino-terminal death effector domains (DED)s, which belong to the death domain superfamily of proteins, can also play key roles during development. Here we describe a novel role for caspase-8 DEDs in regulating cell differentiation and senescence. Caspase-8 DEDs accumulate during terminal differentiation and senescence of epithelial, endothelial and myeloid cells; genetic deletion or shRNA suppression of caspase-8 disrupts cell differentiation, while re-expression of DEDs rescues this phenotype. Among caspase-8 deficient neuroblastoma cells, DED expression attenuated tumor growth in vivo and proliferation in vitro via disruption of mitosis and cytokinesis, resulting in upregulation of p53 and induction of differentiation markers. These events occur independent of caspase-8 catalytic activity, but require a critical lysine (K156) in a microtubule-binding motif in the second DED domain. The results demonstrate a new function for the DEDs of caspase-8, and describe an unexpected mechanism that contributes to cell differentiation and senescence.
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Affiliation(s)
- Ainhoa Mielgo
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Vicente A. Torres
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Michael C. Schmid
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Ryon Graf
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Samantha G. Zeitlin
- Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Pedro Lee
- Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America
| | - David J. Shields
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Simone Barbero
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Colin Jamora
- Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Dwayne G. Stupack
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
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Wells J, Lee B, Cai AQ, Karapetyan A, Lee WJ, Rugg E, Sinha S, Nie Q, Dai X. Ovol2 suppresses cell cycling and terminal differentiation of keratinocytes by directly repressing c-Myc and Notch1. J Biol Chem 2009; 284:29125-35. [PMID: 19700410 DOI: 10.1074/jbc.m109.008847] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Ovol2 belongs to the Ovo family of evolutionarily conserved zinc finger transcription factors that act downstream of key developmental signaling pathways including Wg/Wnt and BMP/TGF-beta. We previously reported Ovol2 expression in the basal layer of epidermis, where epidermal stem/progenitor cells reside. In this work, we use HaCaT human keratinocytes to investigate the cellular and molecular functions of Ovol2. We show that depletion of Ovol2 leads to transient cell expansion but a loss of cells with long term proliferation potential. Mathematical modeling and experimental findings suggest that both faster cycling and precocious withdrawal from the cell cycle underlie this phenotype. Ovol2 depletion also accelerates extracellular signal-induced terminal differentiation in two- and three-dimensional culture models. By chromatin immunoprecipitation, luciferase reporter, and functional rescue assays, we demonstrate that Ovol2 directly represses two critical downstream targets, c-Myc and Notch1, thereby suppressing keratinocyte transient proliferation and terminal differentiation, respectively. These findings shed light on how an epidermal cell maintains a proliferation-competent and differentiation-resistant state.
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Affiliation(s)
- Julie Wells
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, California 92697, USA
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28
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Yokoyama A, Makishima M, Choi M, Cho Y, Nishida S, Hashimoto Y, Terui T. Induction of SREBP-1c mRNA by Differentiation and LXR Ligand in Human Keratinocytes. J Invest Dermatol 2009; 129:1395-401. [DOI: 10.1038/jid.2009.15] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Basement membranes in skin: unique matrix structures with diverse functions? Histochem Cell Biol 2009; 132:1-10. [DOI: 10.1007/s00418-009-0586-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2009] [Indexed: 01/23/2023]
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Micallef L, Belaubre F, Pinon A, Jayat-Vignoles C, Delage C, Charveron M, Simon A. Effects of extracellular calcium on the growth-differentiation switch in immortalized keratinocyte HaCaT cells compared with normal human keratinocytes. Exp Dermatol 2009; 18:143-51. [DOI: 10.1111/j.1600-0625.2008.00775.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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31
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Weber C, Muller-Goymann C. Usefulness of a 3D skin construct in the detection of regenerative effects after previous SDS damage. J Drug Deliv Sci Technol 2009. [DOI: 10.1016/s1773-2247(09)50070-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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32
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Okugawa Y, Hirai Y. Overexpression of Extracellular Epimorphin Leads to Impaired Epidermal Differentiation in HaCaT Keratinocytes. J Invest Dermatol 2008; 128:1884-93. [DOI: 10.1038/jid.2008.22] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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33
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PARAMIO J, JORCANO J. Role of protin kinases in thein vitrodifferentiation of human epidermal HaCaT cells. Br J Dermatol 2008. [DOI: 10.1046/j.1365-2133.1997.17661858.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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34
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SCHÖN M, SCHÖN M, GEILEN C, HOFFMANN M, HAKYI N, ORFANOS C, REUTTER W. Cell-matrix interactions of normal and transformed human keratinocytesin vitroare modulated by the synthetic phospholipid analogue hexadecylphosphocholine. Br J Dermatol 2008. [DOI: 10.1046/j.1365-2133.1996.d01-1065.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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35
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Attama A, Weber C, Müller-Goymann C. Assessment of drug permeation from lipid nanoparticles formulated with a novel structured lipid matrix through artificial skin construct bio-engineered from HDF and HaCaT cell lines. J Drug Deliv Sci Technol 2008. [DOI: 10.1016/s1773-2247(08)50034-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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36
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Stenzinger A, Schreiner D, Pfeiffer T, Tag C, Hofer HW, Wimmer M. Epidermal growth factor-, transforming growth factor-beta-, retinoic acid- and 1,25-dihydroxyvitamin D3-regulated expression of the novel protein PTPIP51 in keratinocytes. Cells Tissues Organs 2007; 184:76-87. [PMID: 17361080 DOI: 10.1159/000098949] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Indexed: 11/19/2022] Open
Abstract
The novel protein PTPIP51 (protein tyrosine phosphatase-interacting protein 51), which has been found to interact with protein tyrosine phosphatases of the PTP1B/TcPTP subfamily, is expressed in all suprabasal layers of human epidermis. Hence, a human keratinocyte cell line (HaCaT) grown on culture slides was used as a simplified model system to study the influence of hormonal agents on the regulation of PTPIP51 expression. Results were obtained by immunocytochemistry and subsequent statistical analysis. Additionally, immunoblotting was performed to detect the possible occurrence of distinct molecular weight forms as described previously. Subcellular localization of PTPIP51 protein was analyzed by specific staining of cellular organelles. HaCaT cells were subjected to treatment with factors that are crucial for the regulation of proliferation and differentiation of keratinocytes in human epidermis: epidermal growth factor (EGF), transforming growth factor-beta(TGF-beta), retinoic acid (RA) and 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)]. Epidermal growth factor receptor (EGFR) expressed in HaCaT cells was inhibited by PD153035. Only about 35% of untreated HaCaT cells were immunoreactive for the PTPIP51 protein. Whereas cells treated with increasing concentrations of 1,25 (OH)(2)D(3) showed a stepwise numerical increase of PTPIP51-positive cells, treatment with RA did not influence the number of PTPIP51-positive cells except when supraphysiological concentrations were applied. Concentration-dependent increase of cells stained positive for PTPIP51 was also observed when HaCaT cells were subjected to EGF treatment. Additional treatment of these cells with PD153035 led to a slight decrease in the fraction of PTPIP51-positive cells, which was not statistically significant. Immunoblotting results suggest a specific pattern of different molecular weight forms of PTPIP51 being expressed in HaCaT cells. Subcellular analysis revealed an association of the protein with mitochondria in nonconfluent cells, whereas confluent cells lack such correlation. The intracellular distribution of PTPIP51 resembled the localization of its interacting partner TcPTP. Furthermore, PTPIP51 was found to be present in both the nucleus and cytoplasm of HaCaT cells. In summary, the results indicate a possible association of PTPIP51 expression with differentiation as well as with apoptosis of keratinocytes.
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Affiliation(s)
- Albrecht Stenzinger
- Institute of Anatomy and Cell Biology, Justus Liebig University Giessen, Giessen, Germany
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37
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Breitkreutz D, Braiman-Wiksman L, Daum N, Denning MF, Tennenbaum T. Protein kinase C family: on the crossroads of cell signaling in skin and tumor epithelium. J Cancer Res Clin Oncol 2007; 133:793-808. [PMID: 17661083 DOI: 10.1007/s00432-007-0280-3] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Accepted: 07/03/2007] [Indexed: 12/28/2022]
Abstract
The protein kinase C (PKC) family represents a large group of phospholipid dependent enzymes catalyzing the covalent transfer of phosphate from ATP to serine and threonine residues of proteins. Phosphorylation of the substrate proteins induces a conformational change resulting in modification of their functional properties. The PKC family consists of at least ten members, divided into three subgroups: classical PKCs (alpha, betaI, betaII, gamma), novel PKCs (delta, epsilon, eta, theta), and atypical PKCs (zeta, iota/lambda). The specific cofactor requirements, tissue distribution, and cellular compartmentalization suggest differential functions and fine tuning of specific signaling cascades for each isoform. Thus, specific stimuli can lead to differential responses via isoform specific PKC signaling regulated by their expression, localization, and phosphorylation status in particular biological settings. PKC isoforms are activated by a variety of extracellular signals and, in turn, modify the activities of cellular proteins including receptors, enzymes, cytoskeletal proteins, and transcription factors. Accordingly, the PKC family plays a central role in cellular signal processing. Accumulating data suggest that various PKC isoforms participate in the regulation of cell proliferation, differentiation, survival and death. These findings have enabled identification of abnormalities in PKC isoform function, as they occur in several cancers. Specifically, the initiation of squamous cell carcinoma formation and progression to the malignant phenotype was found to be associated with distinct changes in PKC expression, activation, distribution, and phosphorylation. These studies were recently further extended to transgenic and knockout animals, which allowed a more direct analysis of individual PKC functions. Accordingly, this review is focused on the involvement of PKC in physiology and pathology of the skin.
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Affiliation(s)
- D Breitkreutz
- Division of Differentiation and Carcinogenesis (A080/A110), German Cancer Research Center (DKFZ), POB 101949, Im Neuenheimer Feld 280, 69009, Heidelberg, Germany.
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38
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Severino A, Abbruzzese C, Manente L, Valderas AA, Mattarocci S, Federico A, Starace G, Chersi A, Mileo AM, Paggi MG. Human papillomavirus-16 E7 interacts with Siva-1 and modulates apoptosis in HaCaT human immortalized keratinocytes. J Cell Physiol 2007; 212:118-25. [PMID: 17348035 DOI: 10.1002/jcp.21011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The viral factor E7 plays a key role in the well-established association between "high-risk" Human Papillomavirus (HPV) infection and the development of epithelial malignant tumors, as uterine cervix and ano-genital cancer. To delve into the molecular mechanisms of HPV-mediated cell transformation, we searched for novel potential cellular targets of the HPV-16 E7 oncoprotein, by means of the yeast two-hybrid technique, identifying a protein-protein interaction between HPV-16 E7 and the pro-apoptotic cellular factor Siva-1. Using co-precipitation assays and the "PepSets" technique, we confirmed this physical interaction and mapped accurately, for both proteins, the amino acid residues involved. Additionally, we found that HPV-16 E7 competed in vitro with the binding of the Bcl-X(L) anti-apoptotic factor to Siva-1, an interaction that has a major inference in UV radiation-induced apoptosis. In HaCaT immortalized human keratinocytes, forced HPV-16 E7 expression by retroviral infection caused Siva-1 transcript up-regulation, detected by cDNA macroarray hybridization and real-time quantitative PCR, paralleled by an increased amount of protein. Confirming the anti-apoptotic role of HPV-16 E7 in the HaCaT cellular model, evaluated by nuclear morphology, we also found that Siva-1 expression produced a significant increase of the apoptotic rate in UV radiation-exposed HaCaT cells, and that this effect resulted explicitly counteracted by HPV-16 E7. Being apoptosis a key physiological process for the elimination of irreversibly injured cells, the anti-apoptotic role of HPV-16 E7, performed at least by its interference with Siva-1, can be considered an additional mechanism for the survival of damaged, potentially transforming, cell clones.
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Affiliation(s)
- Anna Severino
- Department for the Development of Therapeutic Programs, Regina Elena Cancer Institute, Rome, Italy
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39
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Mileo AM, Piombino E, Severino A, Tritarelli A, Paggi MG, Lombardi D. Multiple interference of the human papillomavirus-16 E7 oncoprotein with the functional role of the metastasis suppressor Nm23-H1 protein. J Bioenerg Biomembr 2007; 38:215-25. [PMID: 17103045 DOI: 10.1007/s10863-006-9037-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
High-risk human papillomaviruses (HPV) are linked to human cervical and other ano-genital cancers. Integration of the viral genome in the transformed epithelial cells is restricted to the coding regions for the E6 and E7 oncoproteins. Nevertheless, E7 plays the major role in cell transformation. We report a novel interaction between HPV-16 E7 and the Nm23-H1 and Nm23-H2 proteins identified in yeast by the two-hybrid system and confirmed by co-immunoprecipitation in the human keratinocyte HaCaT cell line. Expression of the E7 oncoprotein in HaCaT cells induces modified keratinocyte proliferation and differentiation patterns, and leads to down-modulation and functional inactivation of the metastasis suppressor Nm23-H1 protein. Both transcriptional down-regulation and protein degradation contribute to reduce Nm23-H1 intracellular content. Besides metastasis suppression, Nm23-H1 displays multiple functions in cell cycle regulation and differentiation, development, DNA regulation and caspase-independent apoptosis. As a consequence of Nm23-H1 inhibition, HPV-16 E7 expressing HaCaT cells, acquire invasiveness capabilities and resistance to granzyme A-induced apoptosis. We propose that impairment of the multifunctional role of Nm23-H1 is an important feature consistent with the complex strategy carried out by HPV-16 E7 to promote cell transformation and tumor progression.
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Affiliation(s)
- Anna Maria Mileo
- Department for the Development of Therapeutic Programs, Laboratory C, Regina Elena Cancer Institute, Centre for Experimental Research, Via delle Messi d'Oro 156, 00158, Rome, Italy
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Abstract
Apoptosis of keratinocytes is a key mechanism required for epidermal homeostasis and the renewal of damaged cells. Its dysregulation has been implicated in many skin diseases including cancer and hyperproliferative disorders. In the present study, the effect of sodium butyrate, a histone deacetylase inhibitor, on keratinocyte apoptosis was investigated using the HaCaT human keratinocyte cell line. Sodium butyrate induced morphological changes associated with apoptosis and nuclear fragmentation of HaCaTs. Annexin V staining demonstrated that sodium butyrate induced apoptosis in a dose and time-dependent manner with 50% of HaCaTs apoptotic after exposure to 0.8 mg/ml sodium butyrate for 24 h. Apoptosis was associated with upregulation of cell surface expression of the death receptor Fas and activation of the extrinsic caspase pathway, with induction of caspase 8 activity peaking after 8 h. Caspase 3 activity peaked after 24 h and was associated with cleavage of the caspase 3 substrate, poly (ADP-ribose) polymerase (PARP). The intrinsic caspase pathway was not activated as caspase 9 activity was not detected, and there was no change in the expression of terminal differentiation markers keratin 10 and involucrin following sodium butyrate treatment. Together these results indicate that sodium butyrate is a potent inducer of Fas associated apoptosis via caspase activation in HaCaT keratinocytes, an effect that is independent of the induction of terminal differentiation.
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Affiliation(s)
- Ilse S Daehn
- Child Health Research Institute, Women's and Children's Hospital, North Adelaide, SA, Australia
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41
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Rotzer D, Krampert M, Sulyok S, Braun S, Stark HJ, Boukamp P, Werner S. Id proteins: novel targets of activin action, which regulate epidermal homeostasis. Oncogene 2006; 25:2070-81. [PMID: 16288215 DOI: 10.1038/sj.onc.1209230] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Activin is a member of the transforming growth factor beta (TGF-beta) family, which plays a crucial role in skin morphogenesis and wound healing. To gain insight into the underlying mechanisms of action, we searched for activin-regulated genes in cultured keratinocytes. One of the identified target genes encodes Id1, a negative regulator of helix-loop-helix transcription factors. We show that Id1, Id2, and Id3 are strongly downregulated by activin in keratinocytes in vitro and in vivo. To determine the role of Id1 in keratinocyte biology, we generated stable HaCaT keratinocyte cell lines overexpressing this protein. Our results revealed that enhanced levels of Id1 do not affect proliferation of keratinocytes in monoculture under exponential culture conditions or in response to activin or TGF-beta1. However, in three-dimensional organotypic cultures, Id1-overexpressing HaCaT cells formed a hyperthickened and disorganized epithelium that was characterized by enhanced keratinocyte proliferation, abnormal differentiation, and an increased rate of apoptosis. These results identify an important function of Id1 in the regulation of epidermal homeostasis.
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Affiliation(s)
- D Rotzer
- Institute of Cell Biology, Department of Biology, ETH Zürich, Hönggerberg, Zürich, Switzerland
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Abstract
The trace element zinc is essential for the survival and function of all cells. Zinc deficiency, whether nutritional or genetic, is fatal if left untreated. The effects of zinc deficiency are particularly obvious in the skin, seen as an erythematous rash, scaly plaques, and ulcers. Electron microscopy reveals degenerative changes within keratinocytes. Despite the well-documented association between zinc deficiency and skin pathology, it is not clear which cellular processes are most sensitive to zinc deficiency and could account for the typical pathological features. We used the cultured HaCaT keratinocyte line to obtain insight into the cellular effects of zinc deficiency, as these cells show many characteristics of normal skin keratinocytes. Zinc deficiency was induced by growing cells in the presence of the zinc chelator, TPEN, or by growth in zinc-deficient medium. Growth of cells in zinc-deficient medium resulted in a 44% reduction of intracellular zinc levels and a 75% reduction in the activity of the zinc-dependent enzyme, 5'-nucleotidase, relative to the control cells. Over a period of 7 days of exposure to zinc-deficient conditions, no changes in cell viability and growth, or in the cytoskeletal and cell adhesion systems, were found in HaCaT cells. At 7 days, however, induction of apoptosis was indicated by the presence of DNA fragmentation and expression of active caspase-3 in cells. These results demonstrate that apoptosis is the earliest detectable cellular change induced by zinc deficiency in HaCaT keratinocytes. Our observations account for many of the features of zinc deficiency, including the presence of degenerate nuclei, chromatin aggregates and abnormal organization of keratin, that may represent the later stages of apoptosis. In summary, a major causal role for apoptosis in the pathology of zinc deficiency in the skin is proposed. This role is consistent with the previously unexplained diverse range of degenerative cellular changes seen at the ultrastructural level in zinc-deficient keratinocytes.
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Affiliation(s)
- Dallas Wilson
- Centre for Cellular and Molecular Biology, Deakin University, Melbourne, Victoria, Australia
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Terron-Kwiatkowski A, van Steensel MAM, van Geel M, Lane EB, McLean WHI, Steijlen PM. Mutation S233L in the 1B domain of keratin 1 causes epidermolytic palmoplantar keratoderma with "tonotubular" keratin. J Invest Dermatol 2006; 126:607-13. [PMID: 16439967 DOI: 10.1038/sj.jid.5700152] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominant genodermatosis characterized by epidermolytic hyperkeratosis restricted to the palm and sole epidermis. The disorder is normally associated with dominant-negative mutations in the keratin 9 (K9) gene; however, a small number of cases have been reported where causative mutations were identified in the K1 gene. Here, we present two unrelated Dutch EPPK families with striking ultrastructural findings: tubular keratin structures in the cytoplasm of suprabasal cells. Similar structures were reported previously in a German EPPK family and were termed "tonotubular" keratin. After excluding the involvement of the K9 gene by complete sequencing, we identified a novel mutation, S233L, at the beginning of the 1B domain of K1 in both families. Protein expression studies in cultured cells indicated pathogenicity of this mutation. This is the first report of a genetic defect in this domain of K1. The unusual gain-of-function mutation points to a subtle role of the 1B domain in mediating filament-filament interactions with regular periodicity.
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Affiliation(s)
- Ana Terron-Kwiatkowski
- Epithelial Genetics Group, Human Genetics Unit, Division of Pathology and Neuroscience, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
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44
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Wang TC, Jee SH, Tsai TF, Huang YL, Tsai WL, Chen RH. Role of breast tumour kinase in the in vitro differentiation of HaCaT cells. Br J Dermatol 2005; 153:282-9. [PMID: 16086737 DOI: 10.1111/j.1365-2133.2005.06604.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Breast tumour kinase (BRK) is a newly identified non-receptor protein tyrosine kinase from a metastatic breast tumour. Its biological functions are still under extensive investigation. The mouse homologue Sik (Src-related intestinal kinase) has been implicated in mouse keratinocyte differentiation; however, not much is known about the functions of BRK in human cutaneous biology. OBJECTIVES Using HaCaT cells as an experimental model, to explore the mutual relationships between BRK and differentiation of human keratinocytes. METHODS Archival paraffin blocks of normal and pathological skin were retrieved for examining the in vivo distribution of BRK. Its expression and subcellular localization were examined via indirect immunofluorescence, and quantitative changes were analysed by Northern and Western blots. The kinase activity of BRK was determined by its autophosphorylation and phosphorylation of exogenous substrate in the in vitro kinase assay. Using a retroviral infection method, we established stably transfected HaCaT cells expressing vector, wild-type BRK or a kinase-defective mutant (K219M). Expression of the differentiation marker keratin 10 (K10) was compared among these cells using semiquantitative reverse transcription-polymerase chain reaction. Results Histochemical examination showed that BRK was expressed exclusively in suprabasal keratinocytes. Its distribution was both cytoplasmic and intranuclear. An enhanced regional suprabasal expression pattern was observed in the confluent areas of cell cultures. The expression of BRK transcript and protein was up-regulated in prolonged confluence culture in a serum-dependent manner. Its kinase activity was activated shortly after the addition of calcium and ionomycin and returned to the basal level within 30 min. Overexpression of wild-type BRK moderately promoted the expression of K10 transcript while the kinase-defective BRK mutant exerted a prominent suppressive effect. CONCLUSIONS The in vivo distribution of BRK and its up-regulation during in vitro differentiation of HaCaT cells, together with the activation of its kinase activity by calcium/ionomycin and its influence on K10 expression, all indicate a role for BRK in the complex process of keratinocyte differentiation.
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Affiliation(s)
- T C Wang
- Department of Dermatology, College of Medicine, National Taiwan University and National Taiwan University Hospital, Taipei, Taiwan
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45
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Barnhart KF, Credille KM, Ambrus A, Dunstan RW. Preservation of phenotype in an organotypic cell culture model of a recessive keratinization defect of Norfolk terrier dogs. Exp Dermatol 2005; 14:481-90. [PMID: 15946235 DOI: 10.1111/j.0906-6705.2005.00306.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The purpose of this study is to reproduce in vitro a recessive keratinization defect of Norfolk terrier dogs characterized by a lack of keratin 10 (K10) production. Keratinocytes from skin biopsy samples of four normal dogs and two affected dogs were cultured organotypically with growth factor-supplemented media in order to stimulate cornification. The cultured epidermis from the normal dogs closely resembled the normal epidermis in vivo and cornified. The cultured epidermis from the affected dogs displayed many phenotypic alterations identified in skin biopsies from dogs with this heritable defect. Immunohistochemistry and immunoblotting showed a marked decrease in K10 from the cultures of the affected keratinocytes, compared to that in K10 from the cultures of the normal keratinocytes. Real-time reverse transcription polymerase chain reaction quantitation showed a 31-fold decrease in K10, a 1.75-fold increase in K1 and a 136-fold increase in K2e between the affected and the normal epidermis. Organotypic keratinocytes showed a 241-fold decrease in K10, a 31-fold decrease in K1 and a 1467-fold decrease in K2e between the affected and normal cultures. Although in vitro keratin expression did not precisely simulate in vivo, the morphology of the normal and the affected epidermis was largely preserved; thus, this culture system may provide an alternative to in vivo investigations for cutaneous research involving cornification.
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Affiliation(s)
- Kirstin F Barnhart
- Department of Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, TX, USA.
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46
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Lunny DP, Weed E, Nolan PM, Marquardt A, Augustin M, Porter RM. Mutations in gasdermin 3 cause aberrant differentiation of the hair follicle and sebaceous gland. J Invest Dermatol 2005; 124:615-21. [PMID: 15737203 DOI: 10.1111/j.0022-202x.2005.23623.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Defolliculated (Dfl) is a spontaneous mouse mutant with a hair-loss phenotype that includes altered sebaceous gland differentiation, short hair shafts, aberrant catagen stage of the hair cycle, and eventual loss of the hair follicle. Recently a similar mutant, finnegan (Fgn), with an identical phenotype was discovered during a phenotypic screen for mutations induced by chemical mutagenesis. The gene underlying the phenotype of both finnegan and defolliculated has been mapped to chromosome 11 and here we show that both mice harbor mutations in gasdermin 3 (Gsdm3), a gene of unknown function. Gsdm3(Dfl) is a B2 insertion near the 3' splice site of exon 7 and Gsdm3(Fgn) is a point mutation T278P. To investigate the role of the gasdermin gene family an antiserum was raised to a peptide highly homologous to all three mouse gasdermins and human gasdermin. Immunohistochemical analysis revealed that gasdermins are expressed specifically in cells at advanced stages of differentiation in the upper epidermis, the differentiating inner root sheath and hair shaft and in the most mature sebocytes of the sebaceous gland and preputial, meibomium, ceruminous gland, and anal glands. This expression pattern suggests a role for gasdermins in differentiation of the epidermis and its appendages.
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Affiliation(s)
- Declan P Lunny
- School of Life Sciences, University of Dundee, Dundee, UK
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47
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Reichrath J, Rafi L, Rech M, Mitschele T, Meineke V, Gärtner BC, Tilgen W, Holick MF. Analysis of the vitamin D system in cutaneous squamous cell carcinomas. J Cutan Pathol 2004; 31:224-31. [PMID: 14984574 DOI: 10.1111/j.0303-6987.2003.00183.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Increasing evidence points at an important function of vitamin D metabolites for growth regulation in various tissues, and new vitamin D analogs are interesting candidates for the treatment of malignancies, including squamous cell carcinomas (SCC). METHODS We have analyzed expression of vitamin D receptor (VDR), vitamin D-25-hydroxylase (25-OHase), 25-hydroxyvitamin D-1 alpha-hydroxylase (1 alpha-OHase), and 1,25-dihydroxyvitamin D-24-hydroxylase (24-OHase) in SCC. RESULTS Intensity of VDR immunoreactivity was increased in SCCs as compared to normal human skin. VDR staining did not correlate with histological type or grading, nor with markers for proliferation, differentiation, or apoptotic cells. Incubation of SCC cell lines (SCL-1, SCL-2) with calcitriol resulted in a dose-dependent suppression of cell proliferation (approximately up to 30%) in vitro, as measured by a tetrazolium salt (WST-1)-based colorimetric assay. RNA levels for VDR, 25-OHase, 1 alpha-OHase, and 24-OHase were significantly elevated in SCCs as compared to HS, as measured by real-time polymerase chain reaction. CONCLUSIONS Our findings demonstrate that modulation of VDR expression and local synthesis or metabolism of vitamin D metabolites may be of importance for growth regulation of SCCs. Additionally, SCCs represent potential targets for therapy with new vitamin D analogs that exert little calcemic side effects or for pharmacological modulation of calcitriol synthesis/metabolism in these tumors.
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Affiliation(s)
- Jörg Reichrath
- Department of Dermatology, The Saarland University Hospital, Homburg, Germany.
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48
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Széll M, Bata-Csörgo Z, Koreck A, Pivarcsi A, Polyánka H, Szeg C, Gaál M, Dobozy A, Kemény L. Proliferating keratinocytes are putative sources of the psoriasis susceptibility-related EDA+ (extra domain A of fibronectin) oncofetal fibronectin. J Invest Dermatol 2004; 123:537-46. [PMID: 15304094 DOI: 10.1111/j.0022-202x.2004.23224.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The extra domain A of fibronectin (EDA+ oncofetal isoform of fibronectin was recently reported to be overexpressed in psoriatic uninvolved epidermis. It has been proposed that the abnormal presence of EDA+ oncofetal protein at the dermal-epidermal junction in the uninvolved skin may provide the "psoriatic" environment in which keratinocytes are in a preactivated state with regard to mitogenic signals (e.g., T cell lymphokines). To determine the possible sources of cellular fibronectin in the non-lesional psoriatic skin, we aimed to investigate whether keratinocytes could produce the EDA+ oncofetal form of fibronectin. RT-PCR studies revealed that both cultured normal keratinocytes and HaCaT cells express the EDA+ splice variant of fibronectin mRNA, and in HaCaT cells the EDA+/EDA- transcript ratio was elevated compared with normal keratinocytes. Cultured keratinocytes and HaCaT cells showed intracytoplasmic staining with an EDA+ fibronectin-specific antibody and among the positively stained cells many showed mitosis. Using RT-PCR, western blot analysis, and flow cytometry, we showed that in synchronized HaCaT cells the amount of both total fibronectin and its EDA+ isoform change with the proliferation/differentiation state of HaCaT cells and peak in highly proliferating cells. We show that in short-term ex vivo cultures, a small population of EDA+ fibronectin containing cell population appear among psoriatic uninvolved, but not normal epidermal cells. We also demonstrate that cell attachment has a strong influence on the expression of both total and EDA+ fibronectin. Our results suggest that proliferating keratinocytes could be the sources of the psoriasis susceptibility-related EDA+ oncofetal fibronectin in the epidermis.
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Affiliation(s)
- Márta Széll
- Dermatological Research Group of the Hungarian Academy of Sciences and the University of Szeged, 6720 Szeged, Korányi fasor 6, Hungary.
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49
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Lemaître G, Lamartine J, Pitaval A, Vaigot P, Garin J, Bouet S, Petat C, Soularue P, Gidrol X, Martin MT, Waksman G. Expression profiling of genes and proteins in HaCaT keratinocytes: Proliferating versus differentiated state. J Cell Biochem 2004; 93:1048-62. [PMID: 15389883 DOI: 10.1002/jcb.20212] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The knowledge of the mechanism of keratinocyte differentiation in culture is still uncompleted. The emergence of new technologies, such as cDNA microarrays or 2D electrophoresis followed by mass spectrometry analysis, has allowed the identification of genes and proteins expressed in biological processes in keratinocytes. Here, we report a genome wide analysis of proliferating versus differentiated human HaCaT keratinocytes. We found that genes and proteins which take part in the cell cycle control, carbohydrate metabolism, cell auto-immunity, adhesion and cytokine signal transduction pathways were regulated in differentiated HaCaT keratinocytes. In addition, we identified seven proteins and 33 transcripts that had not been previously described as differentially expressed in proliferating versus differentiated HaCaT cells. Furthermore, some of these transcripts or proteins were similarly regulated in human primary keratinocytes and in human epidermis. The present study opens new areas of investigation in the comprehension of keratinocyte differentiation.
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Affiliation(s)
- Gilles Lemaître
- Service de Génomique Fonctionnelle, CEA, Département de Radiobiologie et Radiopathologie, Evry, France
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50
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Spinardi L, Rietdorf J, Nitsch L, Bono M, Tacchetti C, Way M, Marchisio PC. A dynamic podosome-like structure of epithelial cells. Exp Cell Res 2004; 295:360-74. [PMID: 15093736 DOI: 10.1016/j.yexcr.2004.01.007] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2003] [Revised: 12/22/2003] [Indexed: 01/15/2023]
Abstract
Focal contacts and hemidesmosomes are cell-matrix adhesion structures of cultured epithelial cells. While focal contacts link the extracellular matrix to microfilaments, hemidesmosomes make connections with intermediate filaments. We have analyzed hemidesmosome assembly in 804G carcinoma cells. Our data show that hemidesmosomes are organized around a core of actin filaments that appears early during cell adhesion. These actin structures look similar to podosomes described in cells of mesenchymal origin. These podosome-like structures are distinct from focal contacts and specifically contain Arp3 (Arp2/3 complex), cortactin, dynamin, gelsolin, N-WASP, VASP, Grb2 and src-like kinase(s). The integrin alpha3beta1 is localized circularly around F-actin cores and co-distributes with paxillin, vinculin, and zyxin. We also show that the maintenance of the actin core and hemidesmosomes is dependent on actin polymerization, src-family kinases, and Grb2, but not on microtubules. Video microscopy analysis reveals that assembly of hemidesmosomes is preceded by recruitment of beta4 integrin subunit to the actin core before its positioning at hemidesmosomes. When 804G cells are induced to migrate, actin cores as well as hemidesmosomes disappear and beta4 integrin subunit becomes co-localized with dynamic actin at leading edges. We show that podosome-like structures are not unique to cells of mesenchymal origin, but also appear in epithelial cells, where they seem to be related to basement membrane adhesion.
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Affiliation(s)
- Laura Spinardi
- DIBIT, Department of Biological and Technological Research, San Raffaele Scientific Institute and University Vita-Salute San Raffaele, 20132 Milan, Italy.
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