1
|
Guan Y, Yang YJ, Nagarajan P, Ge Y. Transcriptional and signalling regulation of skin epithelial stem cells in homeostasis, wounds and cancer. Exp Dermatol 2020; 30:529-545. [PMID: 33249665 DOI: 10.1111/exd.14247] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/10/2020] [Accepted: 11/13/2020] [Indexed: 02/06/2023]
Abstract
The epidermis and skin appendages are maintained by their resident epithelial stem cells, which undergo long-term self-renewal and multilineage differentiation. Upon injury, stem cells are activated to mediate re-epithelialization and restore tissue function. During this process, they often mount lineage plasticity and expand their fates in response to damage signals. Stem cell function is tightly controlled by transcription machineries and signalling transductions, many of which derail in degenerative, inflammatory and malignant dermatologic diseases. Here, by describing both well-characterized and newly emerged pathways, we discuss the transcriptional and signalling mechanisms governing skin epithelial homeostasis, wound repair and squamous cancer. Throughout, we highlight common themes underscoring epithelial stem cell plasticity and tissue-level crosstalk in the context of skin physiology and pathology.
Collapse
Affiliation(s)
- Yinglu Guan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Youn Joo Yang
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Priyadharsini Nagarajan
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yejing Ge
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
2
|
Dinçer T, Boz Er AB, Er İ, Toraman B, Yildiz G, Kalay E. RIPK4 suppresses the TGF-β1 signaling pathway in HaCaT cells. Cell Biol Int 2019; 44:848-860. [PMID: 31825120 DOI: 10.1002/cbin.11282] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 12/06/2019] [Indexed: 12/15/2022]
Abstract
Receptor-interacting serine/threonine kinase 4 (RIPK4) and transforming growth factor-β 1 (TGF-β1) play critical roles in the development and maintenance of the epidermis. A negative correlation between the expression patterns of RIPK4 and TGF-β signaling during epidermal homeostasis-related events and suppression of RIPK4 expression by TGF-β1 in keratinocyte cell lines suggest the presence of a negative regulatory loop between the two factors. So far, RIPK4 has been shown to regulate nuclear factor-κB (NF-κB), protein kinase C (PKC), wingless-type MMTV integration site family (Wnt), and (mitogen-activated protein kinase) MAPK signaling pathways. In this study, we examined the effect of RIPK4 on the canonical Smad-mediated TGF-β1 signaling pathway by using the immortalized human keratinocyte HaCaT cell line. According to our results, RIPK4 inhibits intracellular Smad-mediated TGF-β1 signaling events through suppression of TGF-β1-induced Smad2/3 phosphorylation, which is reflected in the upcoming intracellular events including Smad2/3-Smad4 interaction, nuclear localization, and TGF-β1-induced gene expression. Moreover, the kinase activity of RIPK4 is required for this process. The in vitro wound-scratch assay demonstrated that RIPK4 suppressed TGF-β1-mediated wound healing through blocking TGF-β1-induced cell migration. In conclusion, our results showed the antagonistic effect of RIPK4 on TGF-β1 signaling in keratinocytes for the first time and have the potential to contribute to the understanding and treatment of skin diseases associated with aberrant TGF-β1 signaling.
Collapse
Affiliation(s)
- Tuba Dinçer
- Department of Medical Biology, Faculty of Medicine, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Asiye Büşra Boz Er
- Department of Medical Biology, Institute of Health Science, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - İdris Er
- Department of Medical Biology, Institute of Health Science, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Bayram Toraman
- Department of Medical Biology, Faculty of Medicine, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Gokhan Yildiz
- Department of Medical Biology, Faculty of Medicine, Karadeniz Technical University, 61080, Trabzon, Turkey
| | - Ersan Kalay
- Department of Medical Biology, Faculty of Medicine, Karadeniz Technical University, 61080, Trabzon, Turkey
| |
Collapse
|
3
|
Sümer C, Boz Er AB, Dinçer T. Keratin 14 is a novel interaction partner of keratinocyte differentiation regulator: receptor-interacting protein kinase 4. ACTA ACUST UNITED AC 2019; 43:225-234. [PMID: 31582880 PMCID: PMC6713913 DOI: 10.3906/biy-1904-37] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The epidermis, the outer layer of the skin, is formed by stratified keratinocyte layers. The self-renewal of the epidermis is provided by sustained proliferation and differentiation of the keratinocyte stem cells localized to the basal layer of the epidermis. Receptor-interacting protein kinase 4 (RIPK4) is an important regulator of keratinocyte differentiation, mutations of which are associated with congenital ectodermal malformations. In an attempt to identify the molecular basis of RIPK4’s function, we applied yeast two-hybrid screen (Y2H) and found basal layer-specific keratin filament component keratin 14 (KRT14) as a novel RIPK4-interacting partner. During keratinocyte differentiation, layer-specific keratin composition is tightly regulated. Likewise, the basal layer specific KRT14/keratin 5 (KRT5) heterodimers are replaced by keratin 1 (KRT1)/keratin 10 (KRT10) in suprabasal layers. The regulation of keratin turnover is under the control of signaling associated with posttranslational modifications in which phosphorylation plays a major role. In this study, we verified the KRT14-RIPK4 interaction, which was identified with Y2H, in mammalian cells and showed that the interaction was direct by using proteins expressed in bacteria. According to our results, the N-terminal kinase domain of RIPK4 is responsible for KRT14-RIPK4 interaction; however, the RIPK4 kinase activity is dispensable for the interaction. In accordance with their interaction, RIPK4 and KRT14 colocalize within the cells, particularly at keratin filaments associated with perinuclear ring-like structures. Moreover, RIPK4 did not show any effect on KRT14/KRT5 heterodimer formation. Our results suggest that RIPK4 may regulate the keratin turnover required for keratinocyte differentiation through interacting with KRT14.
Collapse
Affiliation(s)
- Ceren Sümer
- Department of Medical Biology, Institute of Health Science, Karadeniz Technical University, Trabzon Turkey
| | - Asiye Büşra Boz Er
- Department of Medical Biology, Institute of Health Science, Karadeniz Technical University, Trabzon Turkey
| | - Tuba Dinçer
- Department of Medical Biology, Faculty of Medicine, Karadeniz Technical University, Trabzon Turkey
| |
Collapse
|
4
|
Duteil D, Tourrette Y, Eberlin A, Willmann D, Patel D, Friedrichs N, Müller JM, Schüle R. The histone acetyltransferase inhibitor Nir regulates epidermis development. Development 2018; 145:dev.158543. [PMID: 29490983 DOI: 10.1242/dev.158543] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 02/11/2018] [Indexed: 11/20/2022]
Abstract
In addition to its function as an inhibitor of histone acetyltransferases, Nir (Noc2l) binds to p53 and TAp63 to regulate their activity. Here, we show that epidermis-specific ablation of Nir impairs epidermal stratification and barrier function, resulting in perinatal lethality. Nir-deficient epidermis lacks appendages and remains single layered during embryogenesis. Cell proliferation is inhibited, whereas apoptosis and p53 acetylation are increased, indicating that Nir is controlling cell proliferation by limiting p53 acetylation. Transcriptome analysis revealed that Nir regulates the expression of essential factors in epidermis development, such as keratins, integrins and laminins. Furthermore, Nir binds to and controls the expression of p63 and limits H3K18ac at the p63 promoter. Corroborating the stratification defects, asymmetric cell divisions were virtually absent in Nir-deficient mice, suggesting that Nir is required for correct mitotic spindle orientation. In summary, our data define Nir as a key regulator of skin development.
Collapse
Affiliation(s)
- Delphine Duteil
- Urologische Klinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg, Germany
| | - Yves Tourrette
- Urologische Klinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg, Germany
| | - Adrien Eberlin
- Urologische Klinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg, Germany
| | - Dominica Willmann
- Urologische Klinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg, Germany
| | - Dharmeshkumar Patel
- Pediatric Blood and Marrow Transplant, University of Minnesota, 2-191 Moos Tower, 515 Delaware St. SE, Minneapolis, MN 55455, USA
| | - Nicolaus Friedrichs
- Institute of Pathology, University of Cologne Medical School, 50937 Cologne, Germany
| | - Judith M Müller
- Urologische Klinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg, Germany
| | - Roland Schüle
- Urologische Klinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg, Germany .,BIOSS Centre of Biological Signalling Studies, Albert-Ludwigs-University, 79106 Freiburg, Germany.,Deutsche Konsortium für Translationale Krebsforschung (DKTK), Standort, 79106 Freiburg, Germany
| |
Collapse
|
5
|
Khandelwal KD, Ockeloen CW, Venselaar H, Boulanger C, Brichard B, Sokal E, Pfundt R, Rinne T, van Beusekom E, Bloemen M, Vriend G, Revencu N, Carels CEL, van Bokhoven H, Zhou H. Identification of a de novo variant in CHUK in a patient with an EEC/AEC syndrome-like phenotype and hypogammaglobulinemia. Am J Med Genet A 2017; 173:1813-1820. [PMID: 28513979 DOI: 10.1002/ajmg.a.38274] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/17/2017] [Accepted: 04/08/2017] [Indexed: 11/10/2022]
Abstract
The cardinal features of Ectrodactyly, Ectodermal dysplasia, Cleft lip/palate (EEC), and Ankyloblepharon-Ectodermal defects-Cleft lip/palate (AEC) syndromes are ectodermal dysplasia (ED), orofacial clefting, and limb anomalies. EEC and AEC are caused by heterozygous mutations in the transcription factor p63 encoded by TP63. Here, we report a patient with an EEC/AEC syndrome-like phenotype, including ankyloblepharon, ED, cleft palate, ectrodactyly, syndactyly, additional hypogammaglobulinemia, and growth delay. Neither pathogenic mutations in TP63 nor CNVs at the TP63 locus were identified. Exome sequencing revealed de novo heterozygous variants in CHUK (conserved helix-loop-helix ubiquitous kinase), PTGER4, and IFIT2. While the variant in PTGER4 might contribute to the immunodeficiency and growth delay, the variant in CHUK appeared to be most relevant for the EEC/AEC-like phenotype. CHUK is a direct target gene of p63 and encodes a component of the IKK complex that plays a key role in NF-κB pathway activation. The identified CHUK variant (g.101980394T>C; c.425A>G; p.His142Arg) is located in the kinase domain which is responsible for the phosphorylation activity of the protein. The variant may affect CHUK function and thus contribute to the disease phenotype in three ways: (1) the variant exhibits a dominant negative effect and results in an inactive IKK complex that affects the canonical NF-κB pathway; (2) it affects the feedback loop of the canonical and non-canonical NF-κB pathways that are CHUK kinase activity-dependent; and (3) it disrupts NF-κB independent epidermal development that is often p63-dependent. Therefore, we propose that the heterozygous CHUK variant is highly likely to be causative to the EEC/AEC-like and additional hypogammaglobulinemia phenotypes in the patient presented here.
Collapse
Affiliation(s)
- Kriti D Khandelwal
- Department of Orthodontics and Craniofacial Biology, Radboud university medical center, Nijmegen, The Netherlands
| | - Charlotte W Ockeloen
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
| | - Hanka Venselaar
- Centre for Molecular and Biomolecular Informatics, Radboud university medical center, Nijmegen, The Netherlands
| | - Cécile Boulanger
- Department of Pediatric Haematology and Oncology, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Bénédicte Brichard
- Department of Pediatric Haematology and Oncology, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Etienne Sokal
- Université Catholique de Louvain, Cliniques Universitaires St Luc, Service de Gastroentérologie et Hépatologie Pédiatrique, Brussels, Belgium
| | - Rolph Pfundt
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
| | - Tuula Rinne
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
| | - Ellen van Beusekom
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
| | - Marjon Bloemen
- Department of Orthodontics and Craniofacial Biology, Radboud university medical center, Nijmegen, The Netherlands
| | - Gerrit Vriend
- Centre for Molecular and Biomolecular Informatics, Radboud university medical center, Nijmegen, The Netherlands
| | - Nicole Revencu
- Centre for Human Genetics, Cliniques universitaires Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Carine E L Carels
- Department of Orthodontics and Craniofacial Biology, Radboud university medical center, Nijmegen, The Netherlands.,Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands
| | - Hans van Bokhoven
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.,Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands
| | - Huiqing Zhou
- Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.,Department of Molecular Developmental Biology, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| |
Collapse
|
6
|
Hepatic p63 regulates steatosis via IKKβ/ER stress. Nat Commun 2017; 8:15111. [PMID: 28480888 PMCID: PMC5424198 DOI: 10.1038/ncomms15111] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 03/01/2017] [Indexed: 12/28/2022] Open
Abstract
p53 family members control several metabolic and cellular functions. The p53 ortholog p63 modulates cellular adaptations to stress and has a major role in cell maintenance and proliferation. Here we show that p63 regulates hepatic lipid metabolism. Mice with liver-specific p53 deletion develop steatosis and show increased levels of p63. Down-regulation of p63 attenuates liver steatosis in p53 knockout mice and in diet-induced obese mice, whereas the activation of p63 induces lipid accumulation. Hepatic overexpression of N-terminal transactivation domain TAp63 induces liver steatosis through IKKβ activation and the induction of ER stress, the inhibition of which rescues the liver functions. Expression of TAp63, IKKβ and XBP1s is also increased in livers of obese patients with NAFLD. In cultured human hepatocytes, TAp63 inhibition protects against oleic acid-induced lipid accumulation, whereas TAp63 overexpression promotes lipid storage, an effect reversible by IKKβ silencing. Our findings indicate an unexpected role of the p63/IKKβ/ER stress pathway in lipid metabolism and liver disease.
Collapse
|
7
|
Kousa YA, Mansour TA, Seada H, Matoo S, Schutte BC. Shared molecular networks in orofacial and neural tube development. Birth Defects Res 2017; 109:169-179. [DOI: 10.1002/bdra.23598] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 10/17/2016] [Accepted: 10/21/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Youssef A. Kousa
- Pediatric Residency Program; Children's National Health System; Washington DC
| | - Tamer A. Mansour
- Department of Population Health and Reproduction; University of California; Davis California
- Department of Clinical Pathology, College of Medicine; Mansoura University; Egypt
| | - Haitham Seada
- Department of Computer Science and Engineering, Computational Optimization and Innovation Laboratory; Michigan State University; East Lansing Michigan
| | - Samaneh Matoo
- Department of Modern Science; Islamic Azad University-Tehran Medical Branch; Tehran Iran
| | - Brian C. Schutte
- Department of Microbiology and Molecular Genetics and the Department of Pediatrics and Human Development; Michigan State University; East Lansing Michigan
| |
Collapse
|
8
|
XIE YUXIN, XIE KEQI, GOU QIHENG, CHEN NIANYONG. IκB kinase α functions as a tumor suppressor in epithelial-derived tumors through an NF-κB-independent pathway (Review). Oncol Rep 2015; 34:2225-32. [DOI: 10.3892/or.2015.4229] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/06/2015] [Indexed: 11/06/2022] Open
|
9
|
Gollasch B, Basmanav FB, Nanda A, Fritz G, Mahmoudi H, Thiele H, Wehner M, Wolf S, Altmüller J, Nürnberg P, Frank J, Betz RC. Identification of a novel mutation inRIPK4in a kindred with phenotypic features of Bartsocas-Papas and CHAND syndromes. Am J Med Genet A 2015; 167A:2555-62. [DOI: 10.1002/ajmg.a.37233] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 06/15/2015] [Indexed: 12/15/2022]
Affiliation(s)
| | | | - Arti Nanda
- Genetic Skin Diseases Clinic; As'ad Al-Hamad Dermatology Center; Al-Sabah Hospital Kuwait
| | - Günter Fritz
- Department of Neuropathology; Neurozentrum; University of Freiburg; Freiburg Germany
| | | | - Holger Thiele
- Cologne Center for Genomics (CCG); University of Cologne; Cologne Germany
| | - Maria Wehner
- Institute of Human Genetics; University of Bonn; Bonn Germany
| | - Sabrina Wolf
- Institute of Human Genetics; University of Bonn; Bonn Germany
| | - Janine Altmüller
- Cologne Center for Genomics (CCG); University of Cologne; Cologne Germany
- Institute of Human Genetics; University of Cologne; Cologne Germany
| | - Peter Nürnberg
- Cologne Center for Genomics (CCG); University of Cologne; Cologne Germany
- Cluster of Excellence on Cellular Stress Responses in Aging-Associated Diseases (CECAD); University of Cologne; Cologne Germany
- Center for Molecular Medicine Cologne (CMMC); University of Cologne; Cologne Germany
| | - Jorge Frank
- Division of Dermatogenetics and Skin Cancer Center; Department of Dermatology; University of Düsseldorf; Düsseldorf Germany
| | - Regina C. Betz
- Institute of Human Genetics; University of Bonn; Bonn Germany
| |
Collapse
|
10
|
Restelli M, Molinari E, Marinari B, Conte D, Gnesutta N, Costanzo A, Merlo GR, Guerrini L. FGF8, c-Abl and p300 participate in a pathway that controls stability and function of the ΔNp63α protein. Hum Mol Genet 2015; 24:4185-97. [PMID: 25911675 PMCID: PMC4492388 DOI: 10.1093/hmg/ddv151] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/21/2015] [Indexed: 12/22/2022] Open
Abstract
The p63 transcription factor, homolog to the p53 tumor suppressor gene, plays a crucial role in epidermal and limb development, as its mutations are associated to human congenital syndromes characterized by skin, craniofacial and limb defects. While limb and skin-specific p63 transcriptional targets are being discovered, little is known of the post-translation modifications controlling ΔNp63α functions. Here we show that the p300 acetyl-transferase physically interacts in vivo with ΔNp63α and catalyzes its acetylation on lysine 193 (K193) inducing ΔNp63α stabilization and activating specific transcriptional functions. Furthermore we show that Fibroblast Growth Factor-8 (FGF8), a morphogenetic signaling molecule essential for embryonic limb development, increases the binding of ΔNp63α to the tyrosine kinase c-Abl as well as the levels of ΔNp63α acetylation. Notably, the natural mutant ΔNp63α-K193E, associated to the Split-Hand/Foot Malformation-IV syndrome, cannot be acetylated by this pathway. This mutant ΔNp63α protein displays promoter-specific loss of DNA binding activity and consequent altered expression of development-associated ΔNp63α target genes. Our results link FGF8, c-Abl and p300 in a regulatory pathway that controls ΔNp63α protein stability and transcriptional activity. Hence, limb malformation-causing p63 mutations, such as the K193E mutation, are likely to result in aberrant limb development via the combined action of altered protein stability and altered promoter occupancy.
Collapse
Affiliation(s)
- Michela Restelli
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Elisa Molinari
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Barbara Marinari
- Dermatology Unit, NESMOS Department, Università di Roma La Sapienza, I-00189 Rome, Italy and
| | - Daniele Conte
- Department of Molecular Biotechnologies and Health Sciences, Università di Torino, I-10126 Torino, Italy
| | - Nerina Gnesutta
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Antonio Costanzo
- Dermatology Unit, NESMOS Department, Università di Roma La Sapienza, I-00189 Rome, Italy and
| | - Giorgio Roberto Merlo
- Department of Molecular Biotechnologies and Health Sciences, Università di Torino, I-10126 Torino, Italy
| | - Luisa Guerrini
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy,
| |
Collapse
|
11
|
Koster MI, Dinella J, Chen J, O'Shea C, Koch PJ. Integrating animal models and in vitro tissue models to elucidate the role of desmosomal proteins in diseases. ACTA ACUST UNITED AC 2014; 21:55-63. [PMID: 24460201 DOI: 10.3109/15419061.2013.876015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Desmosomes are intercellular junctions that provide tissues with structural stability. These junctions might also act as signaling centers that transmit environmental clues to the cell, thereby affecting cell differentiation, migration, and proliferation. The importance of desmosomes is underscored by devastating skin and heart diseases caused by mutations in desmosomal genes. Recent observations suggest that abnormal desmosomal protein expression might indirectly contribute to skin disorders previously not linked to these proteins. For example, it has been postulated that reduced desmosomal protein expression occurs in patients affected by Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome (AEC), a skin fragility disorder caused by mutations in the transcription factor TP63. Currently, it is not clear how these changes in desmosomal gene expression contribute to AEC. We will discuss new approaches that combine in vitro and in vivo models to elucidate the role of desmosomal gene deregulation in human skin diseases such as AEC.
Collapse
Affiliation(s)
- Maranke I Koster
- Department of Dermatology, University of Colorado School of Medicine and Charles C Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado School of Medicine , Aurora, CO , USA
| | | | | | | | | |
Collapse
|
12
|
Costanzo A, Pediconi N, Narcisi A, Guerrieri F, Belloni L, Fausti F, Botti E, Levrero M. TP63 and TP73 in cancer, an unresolved "family" puzzle of complexity, redundancy and hierarchy. FEBS Lett 2014; 588:2590-9. [PMID: 24983500 DOI: 10.1016/j.febslet.2014.06.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 06/16/2014] [Accepted: 06/16/2014] [Indexed: 12/24/2022]
Abstract
TP53 belongs to a small gene family that includes, in mammals, two additional paralogs, TP63 and TP73. The p63 and p73 proteins are structurally and functionally similar to p53 and their activity as transcription factors is regulated by a wide repertoire of shared and unique post-translational modifications and interactions with regulatory cofactors. p63 and p73 have important functions in embryonic development and differentiation but are also involved in tumor suppression. The biology of p63 and p73 is complex since both TP63 and TP73 genes are transcribed into a variety of different isoforms that give rise to proteins with antagonistic properties, the TA-isoforms that act as tumor-suppressors and DN-isoforms that behave as proto-oncogenes. The p53 family as a whole behaves as a signaling "network" that integrates developmental, metabolic and stress signals to control cell metabolism, differentiation, longevity, proliferation and death. Despite the progress of our knowledge, the unresolved puzzle of complexity, redundancy and hierarchy in the p53 family continues to represent a formidable challenge.
Collapse
Affiliation(s)
- Antonio Costanzo
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Natalia Pediconi
- Laboratory of Molecular Oncology, Department of Molecular Medicine, Sapienza University of Rome, Italy; Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy
| | - Alessandra Narcisi
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Francesca Guerrieri
- Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy; Laboratory of Gene Expression, Department of Internal Medicine (DMISM), Sapienza University of Rome, Italy
| | - Laura Belloni
- Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy; Laboratory of Gene Expression, Department of Internal Medicine (DMISM), Sapienza University of Rome, Italy
| | - Francesca Fausti
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Elisabetta Botti
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Massimo Levrero
- Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy; Laboratory of Gene Expression, Department of Internal Medicine (DMISM), Sapienza University of Rome, Italy.
| |
Collapse
|
13
|
Yan M, Zhang Y, He B, Xiang J, Wang ZF, Zheng FM, Xu J, Chen MY, Zhu YL, Wen HJ, Wan XB, Yue CF, Yang N, Zhang W, Zhang JL, Wang J, Wang Y, Li LH, Zeng YX, Lam EWF, Hung MC, Liu Q. IKKα restoration via EZH2 suppression induces nasopharyngeal carcinoma differentiation. Nat Commun 2014; 5:3661. [DOI: 10.1038/ncomms4661] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 03/14/2014] [Indexed: 02/07/2023] Open
|
14
|
Koch PJ, Dinella J, Fete M, Siegfried EC, Koster MI. Modeling AEC-New approaches to study rare genetic disorders. Am J Med Genet A 2014; 164A:2443-54. [PMID: 24665072 DOI: 10.1002/ajmg.a.36455] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 01/03/2014] [Indexed: 11/06/2022]
Abstract
Ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome is a rare monogenetic disorder that is characterized by severe abnormalities in ectoderm-derived tissues, such as skin and its appendages. A major cause of morbidity among affected infants is severe and chronic skin erosions. Currently, supportive care is the only available treatment option for AEC patients. Mutations in TP63, a gene that encodes key regulators of epidermal development, are the genetic cause of AEC. However, it is currently not clear how mutations in TP63 lead to the various defects seen in the patients' skin. In this review, we will discuss current knowledge of the AEC disease mechanism obtained by studying patient tissue and genetically engineered mouse models designed to mimic aspects of the disorder. We will then focus on new approaches to model AEC, including the use of patient cells and stem cell technology to replicate the disease in a human tissue culture model. The latter approach will advance our understanding of the disease and will allow for the development of new in vitro systems to identify drugs for the treatment of skin erosions in AEC patients. Further, the use of stem cell technology, in particular induced pluripotent stem cells (iPSC), will enable researchers to develop new therapeutic approaches to treat the disease using the patient's own cells (autologous keratinocyte transplantation) after correction of the disease-causing mutations.
Collapse
Affiliation(s)
- Peter J Koch
- Department of Dermatology, University of Colorado School of Medicine, Aurora, Colorado; Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado; Charles C. Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado School of Medicine, Aurora, Colorado; Graduate Program in Cell Biology, Stem Cells and Development, University of Colorado School of Medicine, Aurora, Colorado
| | | | | | | | | |
Collapse
|
15
|
Remels AHV, Gosker HR, Langen RC, Polkey M, Sliwinski P, Galdiz J, van den Borst B, Pansters NA, Schols AMWJ. Classical NF-κB activation impairs skeletal muscle oxidative phenotype by reducing IKK-α expression. Biochim Biophys Acta Mol Basis Dis 2013; 1842:175-85. [PMID: 24215713 DOI: 10.1016/j.bbadis.2013.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 10/28/2013] [Accepted: 11/01/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Loss of quadriceps muscle oxidative phenotype (OXPHEN) is an evident and debilitating feature of chronic obstructive pulmonary disease (COPD). We recently demonstrated involvement of the inflammatory classical NF-κB pathway in inflammation-induced impairments in muscle OXPHEN. The exact underlying mechanisms however are unclear. Interestingly, IκB kinase α (IKK-α: a key kinase in the alternative NF-κB pathway) was recently identified as a novel positive regulator of skeletal muscle OXPHEN. We hypothesised that inflammation-induced classical NF-κB activation contributes to loss of muscle OXPHEN in COPD by reducing IKK-α expression. METHODS Classical NF-κB signalling was activated (molecularly or by tumour necrosis factor α: TNF-α) in cultured myotubes and the impact on muscle OXPHEN and IKK-α levels was investigated. Moreover, the alternative NF-κB pathway was modulated to investigate the impact on muscle OXPHEN in absence or presence of an inflammatory stimulus. As a proof of concept, quadriceps muscle biopsies of COPD patients and healthy controls were analysed for expression levels of IKK-α, OXPHEN markers and TNF-α. RESULTS IKK-α knock-down in cultured myotubes decreased expression of OXPHEN markers and key OXPHEN regulators. Moreover, classical NF-κB activation (both by TNF-α and IKK-β over-expression) reduced IKK-α levels and IKK-α over-expression prevented TNF-α-induced impairments in muscle OXPHEN. Importantly, muscle IKK-α protein abundance and OXPHEN was reduced in COPD patients compared to controls, which was more pronounced in patients with increased muscle TNF-α mRNA levels. CONCLUSION Classical NF-κB activation impairs skeletal muscle OXPHEN by reducing IKK-α expression. TNF-α-induced reductions in muscle IKK-α may accelerate muscle OXPHEN deterioration in COPD.
Collapse
Key Words
- 3-monooxygenase/tryptophan 5-monooxygenase activation protein, zeta polypeptide
- 50S ribosomal subunit protein L15
- 60S ribosomal protein L13a
- ACTB
- ALAS1
- ATP
- Ad
- Adenosine triphosphate
- Adenoviral
- B2M
- BMI
- Beta Cytoskeletal Actin
- Body mass index
- CA
- COPD
- COXIV
- CS
- Chronic obstructive pulmonary disease
- Citrate synthase
- Classical NF-κB
- Constitutively active
- Cytochrome c oxidase 4
- DMEM
- Delta-aminolevulinate synthase 1
- Dulbecco's Modified Eagle Medium
- FEV1
- FVC
- Forced expiratory volume in one second
- Forced vital capacity
- GAPDH
- GUSB
- Gapdh, Glyceraldehyde-3-phosphate dehydrogenase
- Gfp
- Glucuronidase, bèta
- Green fluorescent protein
- HAD
- HBSS
- HCBP
- HMBS
- HPRT
- Hank's Balanced Salt solution
- Hprt, Hypoxanthine phosphoribosyltransferase 1
- Human carnitine-palmitoyl transferase B
- Hydroxymethylbilane Synthase
- IKK-α
- Icam-1
- Ikk-α, IκB kinase alpha
- Ikk-β
- Il-1β
- Intra-cellular adhesion molecule 1
- IκB kinase beta
- IκBα
- Mlc
- Myhc
- Myosin heavy chain
- Myosin light chain
- NF-κB
- NS
- Not significant
- Nrf
- Nuclear factor kappa B
- Nuclear respiratory factor
- OXPHEN
- Oxidative metabolism
- Oxidative phenotype
- Oxidative phosphorylation
- Oxphos
- PBS
- PGC-1
- PPAR
- PPIA
- Pgc-1, Peroxisome proliferator-activated receptor gamma co-activator 1
- Phosphate-buffered saline
- Ppar, Peroxisome proliferator-activated receptor
- RPL13A
- RPLO
- SD
- SEM
- SR
- Skeletal muscle
- Standard deviation
- Standard equality of the mean
- Super repressor
- TFAM
- TNF-α
- Tfam, Mitochondrial transcription factor A
- Tnf-α, Tumour necrosis factor alpha
- UBC
- Ubiquitin C
- WT
- Wild-type
- YWHAZ
- interleukin 1β
- nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha
- peptidylprolyl isomerase A (cyclophilin A)
- β-hydroxyacyl-CoA dehydrogenase
- β2m, Beta 2 microglobulin
Collapse
Affiliation(s)
- A H V Remels
- NUTRIM School for Nutrition, Toxicology & Metabolism, Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht, the Netherlands.
| | - H R Gosker
- NUTRIM School for Nutrition, Toxicology & Metabolism, Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht, the Netherlands.
| | - R C Langen
- NUTRIM School for Nutrition, Toxicology & Metabolism, Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht, the Netherlands.
| | - M Polkey
- NIHR Respiratory Biomedical Research unit, Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London SW3 6NP, UK.
| | - P Sliwinski
- Department of Respiratory Medicine, Institute of Tuberculosis and Lung Diseases, Warsaw, Poland.
| | - J Galdiz
- Pneumology Department and Research Unit, Cruces Hospital, Basque Country University, Barakaldo, Spain.
| | - B van den Borst
- NUTRIM School for Nutrition, Toxicology & Metabolism, Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht, the Netherlands.
| | - N A Pansters
- NUTRIM School for Nutrition, Toxicology & Metabolism, Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht, the Netherlands
| | - A M W J Schols
- NUTRIM School for Nutrition, Toxicology & Metabolism, Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht, the Netherlands.
| |
Collapse
|
16
|
Mouse Genetic Models Reveal Surprising Functions of IkB Kinase Alpha in Skin Development and Skin Carcinogenesis. Cancers (Basel) 2013; 5:170-83. [PMID: 24216703 PMCID: PMC3730312 DOI: 10.3390/cancers5010170] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 01/25/2013] [Accepted: 02/06/2013] [Indexed: 01/05/2023] Open
Abstract
Gene knockout studies unexpectedly reveal a pivotal role for IκB kinase alpha (IKKα) in mouse embryonic skin development. Skin carcinogenesis experiments show that Ikkα heterozygous mice are highly susceptible to chemical carcinogen or ultraviolet B light (UVB) induced benign and malignant skin tumors in comparison to wild-type mice. IKKα deletion mediated by keratin 5 (K5).Cre or K15.Cre in keratinocytes induces epidermal hyperplasia and spontaneous skin squamous cell carcinomas (SCCs) in Ikkα floxed mice. On the other hand, transgenic mice overexpressing IKKα in the epidermis, under the control of a truncated loricrin promoter or K5 promoter, develop normal skin and show no defects in the formation of the epidermis and other epithelial organs, and the transgenic IKKα represses chemical carcinogen or UVB induced skin carcinogenesis. Moreover, IKKα deletion mediated by a mutation, which generates a stop codon in the Ikkα gene, has been reported in a human autosomal recessive lethal syndrome. Downregulated IKKα and Ikkα mutations and deletions are found in human skin SCCs. The collective evidence not only highlights the importance of IKKα in skin development, maintaining skin homeostasis, and preventing skin carcinogenesis, but also demonstrates that mouse models are extremely valuable tools for revealing the mechanisms underlying these biological events, leading our studies from bench side to bedside.
Collapse
|
17
|
Fujimoto A, Kurban M, Nakamura M, Farooq M, Fujikawa H, Kibbi AG, Ito M, Dahdah M, Matta M, Diab H, Shimomura Y. GJB6, of which mutations underlie Clouston syndrome, is a potential direct target gene of p63. J Dermatol Sci 2012; 69:159-66. [PMID: 23219093 DOI: 10.1016/j.jdermsci.2012.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 11/06/2012] [Accepted: 11/08/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Clouston syndrome is a rare autosomal dominant condition characterized by hypotrichosis, nail dystrophy, and occasionally palmoplantar keratoderma. The disease is caused by mutations in GJB6 gene, which encodes a gap junction protein connexin 30 (Cx30). OBJECTIVE To disclose the molecular basis of Clouston syndrome in a Lebanese-German family, and also to determine precise expression of Cx30 in normal skin of humans and mice, as well as transcriptional regulation for the GJB6 expression. METHODS We searched for mutations in the GJB6 gene using DNA of the family members with Clouston syndrome. We performed immunostaining to localize the Cx30 expression in normal human skin and mouse embryos. In addition, we did a series of in vitro studies to investigate if the GJB6 could be a direct transcriptional target gene of p63. RESULTS We identified a recurrent heterozygous mutation c.31G>C (p.Gly11Arg) in the GJB6 gene in the Lebanese-German family with Clouston syndrome. Immunostaining in normal human skin sections demonstrated predominant expression of Cx30 in hair follicles, nails, and palmoplantar epidermis, which partially overlapped with p63 expression. We also showed co-expression of Cx30 and p63 in developing mouse hair follicles and nail units. In cultured cells, the GJB6 expression was significantly upregulated by ΔNp63α isoform. Further in vitro analyses suggested that ΔNp63α was potentially involved in the GJB6 expression via binding to the sequences in intron 1 of the GJB6 gene. CONCLUSION Our data further underscore the crucial roles of Cx30 in morphogenesis and development of skin and its appendages.
Collapse
Affiliation(s)
- Atsushi Fujimoto
- Laboratory of Genetic Skin Diseases, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Ferone G, Mollo MR, Thomason HA, Antonini D, Zhou H, Ambrosio R, De Rosa L, Salvatore D, Getsios S, van Bokhoven H, Dixon J, Missero C. p63 control of desmosome gene expression and adhesion is compromised in AEC syndrome. Hum Mol Genet 2012; 22:531-43. [PMID: 23108156 PMCID: PMC3542863 DOI: 10.1093/hmg/dds464] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Ankyloblepharon, ectodermal defects, cleft lip/palate (AEC) syndrome is a rare autosomal dominant disorder caused by mutations in the p63 gene, essential for embryonic development of stratified epithelia. The most severe cutaneous manifestation of this disorder is the long-lasting skin fragility associated with severe skin erosions after birth. Using a knock-in mouse model for AEC syndrome, we found that skin fragility was associated with microscopic blistering between the basal and suprabasal compartments of the epidermis and reduced desmosomal contacts. Expression of desmosomal cadherins and desmoplakin was strongly reduced in AEC mutant keratinocytes and in newborn epidermis. A similar impairment in desmosome gene expression was observed in human keratinocytes isolated from AEC patients, in p63-depleted keratinocytes and in p63 null embryonic skin, indicating that p63 mutations causative of AEC syndrome have a dominant-negative effect on the wild-type p63 protein. Among the desmosomal components, desmocollin 3, desmoplakin and desmoglein 1 were the most significantly reduced by mutant p63 both at the RNA and protein levels. Chromatin immunoprecipitation experiments and transactivation assays revealed that p63 controls these genes at the transcriptional level. Consistent with reduced desmosome function, AEC mutant and p63-deficient keratinocytes had an impaired ability to withstand mechanical stress, which was alleviated by epidermal growth factor receptor inhibitors known to stabilize desmosomes. Our study reveals that p63 is a crucial regulator of a subset of desmosomal genes and that this function is impaired in AEC syndrome. Reduced mechanical strength resulting from p63 mutations can be alleviated pharmacologically by increasing desmosome adhesion with possible therapeutic implications.
Collapse
|
19
|
Clements SE, Techanukul T, Lai-Cheong JE, Mee JB, South AP, Pourreyron C, Burrows NP, Mellerio JE, McGrath JA. Mutations in AEC syndrome skin reveal a role for p63 in basement membrane adhesion, skin barrier integrity and hair follicle biology. Br J Dermatol 2012; 167:134-44. [PMID: 22329826 DOI: 10.1111/j.1365-2133.2012.10888.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AEC (ankyloblepharon-ectodermal defects-clefting) syndrome is an autosomal dominant ectodermal dysplasia disorder caused by mutations in the transcription factor p63. Clinically, the skin is dry and often fragile; other features can include partial eyelid fusion (ankyloblepharon), hypodontia, orofacial clefting, sparse hair or alopecia, and nail dystrophy. OBJECTIVES To investigate how p63 gene mutations affect gene and protein expression in AEC syndrome skin. METHODS We performed microarray analysis on samples of intact and eroded AEC syndrome skin compared with control skin. Changes were verified by quantitative real-time reverse transcription-polymerase chain reaction and, for basal keratinocyte-associated genes, by immunohistochemistry and analysis of microdissected skin. RESULTS We identified significant upregulation of six genes and downregulation of 69 genes in AEC syndrome skin, with the main changes in genes implicated in epidermal adhesion, skin barrier formation and hair follicle biology. There was reduced expression of genes encoding the basement membrane proteins FRAS1 and collagen VII, as well as the skin barrier-associated small proline-rich proteins 1A and 4, late cornified envelope protein 5A, hornerin, and lipid transporters including ALOX15B. Reduced expression of the hair-associated keratins 25, 27, 31, 33B, 34, 35, 81 and 85 was also noted. We also confirmed similar alterations in gene expression for 26 of the 75 genes in eroded AEC scalp skin. CONCLUSIONS This study identifies specific changes in skin structural biology and signalling pathways that result from mutant p63 and provides new molecular insight into the AEC syndrome phenotype.
Collapse
Affiliation(s)
- S E Clements
- St John's Institute of Dermatology, King's College London (Guy's Campus), London SE1 9RT, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Ferone G, Thomason HA, Antonini D, De Rosa L, Hu B, Gemei M, Zhou H, Ambrosio R, Rice DP, Acampora D, van Bokhoven H, Del Vecchio L, Koster MI, Tadini G, Spencer-Dene B, Dixon M, Dixon J, Missero C. Mutant p63 causes defective expansion of ectodermal progenitor cells and impaired FGF signalling in AEC syndrome. EMBO Mol Med 2012; 4:192-205. [PMID: 22247000 PMCID: PMC3376849 DOI: 10.1002/emmm.201100199] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 12/07/2011] [Accepted: 12/08/2011] [Indexed: 11/11/2022] Open
Abstract
Ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome, which is characterized by cleft palate and severe defects of the skin, is an autosomal dominant disorder caused by mutations in the gene encoding transcription factor p63. Here, we report the generation of a knock-in mouse model for AEC syndrome (p63(+/L514F) ) that recapitulates the human disorder. The AEC mutation exerts a selective dominant-negative function on wild-type p63 by affecting progenitor cell expansion during ectodermal development leading to a defective epidermal stem cell compartment. These phenotypes are associated with impairment of fibroblast growth factor (FGF) signalling resulting from reduced expression of Fgfr2 and Fgfr3, direct p63 target genes. In parallel, a defective stem cell compartment is observed in humans affected by AEC syndrome and in Fgfr2b(-/-) mice. Restoring Fgfr2b expression in p63(+/L514F) epithelial cells by treatment with FGF7 reactivates downstream mitogen-activated protein kinase signalling and cell proliferation. These findings establish a functional link between FGF signalling and p63 in the expansion of epithelial progenitor cells and provide mechanistic insights into the pathogenesis of AEC syndrome.
Collapse
|
21
|
Mitchell K, O'Sullivan J, Missero C, Blair E, Richardson R, Anderson B, Antonini D, Murray J, Shanske A, Schutte B, Romano RA, Sinha S, Bhaskar S, Black G, Dixon J, Dixon M. Exome sequence identifies RIPK4 as the Bartsocas-Papas syndrome locus. Am J Hum Genet 2012; 90:69-75. [PMID: 22197488 DOI: 10.1016/j.ajhg.2011.11.013] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 10/14/2011] [Accepted: 11/14/2011] [Indexed: 10/14/2022] Open
Abstract
Pterygium syndromes are complex congenital disorders that encompass several distinct clinical conditions characterized by multiple skin webs affecting the flexural surfaces often accompanied by craniofacial anomalies. In severe forms, such as in the autosomal-recessive Bartsocas-Papas syndrome, early lethality is common, complicating the identification of causative mutations. Using exome sequencing in a consanguineous family, we identified the homozygous mutation c.1127C>A in exon 7 of RIPK4 that resulted in the introduction of the nonsense mutation p.Ser376X into the encoded ankyrin repeat-containing kinase, a protein that is essential for keratinocyte differentiation. Subsequently, we identified a second mutation in exon 2 of RIPK4 (c.242T>A) that resulted in the missense variant p.Ile81Asn in the kinase domain of the protein. We have further demonstrated that RIPK4 is a direct transcriptional target of the protein p63, a master regulator of stratified epithelial development, which acts as a nodal point in the cascade of molecular events that prevent pterygium syndromes.
Collapse
|
22
|
A symphony of regulations centered on p63 to control development of ectoderm-derived structures. J Biomed Biotechnol 2011; 2011:864904. [PMID: 21716671 PMCID: PMC3118300 DOI: 10.1155/2011/864904] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 01/25/2011] [Accepted: 03/16/2011] [Indexed: 12/27/2022] Open
Abstract
The p53-related transcription factor p63 is critically important for basic cellular functions during development of the ectoderm and derived structure and tissues, including skin, limb, palate, and hair. On the one side, p63 is required to sustain the proliferation of keratinocyte progenitors, while on the other side it is required for cell stratification, commitment to differentiate, cell adhesion, and epithelial-mesenchymal signaling. Molecules that are components or regulators of the p63 pathway(s) are rapidly being identified, and it comes with no surprise that alterations in the p63 pathway lead to congenital conditions in which the skin and other ectoderm-derived structures are affected. In this paper, we summarize the current knowledge of the molecular and cellular regulations centered on p63, derived from the comprehension of p63-linked human diseases and the corresponding animal models, as well as from cellular models and high-throughput molecular approaches. We point out common themes and features, that allow to speculate on the possible role of p63 downstream events and their potential exploitation in future attempts to correct the congenital defect in preclinical studies.
Collapse
|
23
|
Abstract
The transcription factor p63 is essential for the formation of the epidermis and other stratifying epithelia. This is clearly demonstrated by the severe abnormality of p63-deficient mice and by the development of certain types of ectodermal dysplasias in humans as a result of p63 mutations. Investigation of the in vivo functions of p63 is complicated by the occurrence of 10 different splicing isoforms and by its interaction with the other family members, p53 and p73. In vitro and in vivo models have been used to unravel the functions of p63 and its different isoforms, but the results or their interpretation are often contradictory. This review focuses on what mammalian in vivo models and patient studies have taught us in the last 10 years.
Collapse
Affiliation(s)
- Hans Vanbokhoven
- Department of Human Genetics, Molecular Neurogenetics Unit, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | | | | | | |
Collapse
|
24
|
Induction of ΔNp63 by the newly identified keratinocyte-specific transforming growth factor β Signaling Pathway with Smad2 and IκB Kinase α in squamous cell carcinoma. Neoplasia 2011; 12:969-79. [PMID: 21170261 DOI: 10.1593/neo.101054] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 09/19/2010] [Accepted: 09/28/2010] [Indexed: 11/18/2022]
Abstract
The expression of p63 (TP63/p51) occurs in the basal cells of stratified epithelia and is strongly enhanced at the early stages of squamous cell carcinomas (SCCs) of the head and neck, skin, cervix, and others. We analyzed a promoter/enhancer region (2kΔN) that drives the predominant expression of ΔNp63 for sensitivity to Smad signaling pathways. Reporter assays in HepG2 cells showed a moderate activation of 2kΔN by Smad2 and IκB kinase α (IKKα), partners of the newly identified keratinocyte-specific transforming growth factor β (TGF-β) signaling, but not by other Smad molecules. In A431 cells, 2kΔN was activated by Smad2 and IKKα, for which a Smad binding element (SMD2) at -204 was essential. Binding of Smad2 to the chromosomal SMD2 site was detectable. The association of Smad2 with IKKα was evident in the nucleus of A431, accounting for the enhancement of ΔNp63 expression by TGF-β. Moreover, both ΔNp63 and IKKα were necessary to maintain the noninvasive phenotype of this cell line. FaDu, an invasive, Smad4-deficient SCC, also allowed 2kΔN transactivation by transfected Smad2 in the presence of endogenous IKKα. Reflecting the lack of chromosomal SMD2-Smad2 association and the absence of nuclear IKKα, however, endogenous ΔNp63 was not controlled by TGF-β or IKKα in FaDu. SCC tissue arrays showed nuclear accumulation of IKKα and p63 intensification in well-differentiated noninvasive lesions. This study indicates that p63 is a target gene of the proposed keratinocyte-specific TGF-β signal pathway for suppression of the malignant conversion of SCC.
Collapse
|
25
|
Boominathan L. The guardians of the genome (p53, TA-p73, and TA-p63) are regulators of tumor suppressor miRNAs network. Cancer Metastasis Rev 2011; 29:613-39. [PMID: 20922462 DOI: 10.1007/s10555-010-9257-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The tumor suppressor p53 homologues, TA-p73, and p63 have been shown to function as tumor suppressors. However, how they function as tumor suppressors remains elusive. Here, I propose a number of tumor suppressor pathways that illustrate how the TA-p73 and p63 could function as negative regulators of invasion, metastasis, and cancer stem cells (CSCs) proliferation. Furthermore, I provide molecular insights into how TA-p73 and p63 could function as tumor suppressors. Remarkably, the guardians--p53, p73, and p63--of the genome are in control of most of the known tumor suppressor miRNAs, tumor suppressor genes, and metastasis suppressors by suppressing c-myc through miR-145/let-7/miR-34/TRIM32/PTEN/FBXW7. In particular, p53 and TA-p73/p63 appear to upregulate the expression of (1) tumor suppressor miRNAs, such as let-7, miR-34, miR-15/16a, miR-145, miR-29, miR-26, miR-30, and miR-146a; (2) tumor suppressor genes, such as PTEN, RBs, CDKN1a/b/c, and CDKN2a/b/c/d; (3) metastasis suppressors, such as Raf kinase inhibitory protein, CycG2, and DEC2, and thereby they enlarge their tumor suppressor network to inhibit tumorigenesis, invasion, angiogenesis, migration, metastasis, and CSCs proliferation.
Collapse
|
26
|
LeBoeuf M, Terrell A, Trivedi S, Sinha S, Epstein JA, Olson EN, Morrisey EE, Millar SE. Hdac1 and Hdac2 act redundantly to control p63 and p53 functions in epidermal progenitor cells. Dev Cell 2010; 19:807-18. [PMID: 21093383 DOI: 10.1016/j.devcel.2010.10.015] [Citation(s) in RCA: 191] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 10/26/2010] [Accepted: 10/26/2010] [Indexed: 11/19/2022]
Abstract
Epidermal and hair follicle development from surface ectodermal progenitor cells requires coordinated changes in gene expression. Histone deacetylases alter gene expression programs through modification of chromatin and transcription factors. We find that deletion of ectodermal Hdac1 and Hdac2 results in dramatic failure of hair follicle specification and epidermal proliferation and stratification, phenocopying loss of the key ectodermal transcription factor p63. Although expression of p63 and its positively regulated basal cell targets is maintained in Hdac1/2-deficient ectoderm, targets of p63-mediated repression, including p21, 14-3-3σ, and p16/INK4a, are ectopically expressed, and HDACs bind and are active at their promoter regions in normal undifferentiated keratinocytes. Mutant embryos display increased levels of acetylated p53, which opposes p63 functions, and p53 is required for HDAC inhibitor-mediated p21 expression in keratinocytes. Our data identify critical requirements for HDAC1/2 in epidermal development and indicate that HDAC1/2 directly mediate repressive functions of p63 and suppress p53 activity.
Collapse
Affiliation(s)
- Matthew LeBoeuf
- Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, 19104, USA
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
The transcription factor p63 is critically important for skin development and maintenance. Processes that require p63 include epidermal lineage commitment, epidermal differentiation, cell adhesion, and basement membrane formation. Not surprisingly, alterations in the p63 pathway underlie a subset of ectodermal dysplasias, developmental syndromes in which the skin and skin appendages do not develop normally. This review summarizes the current understanding of the role of p63 in normal development and ectodermal dysplasias.
Collapse
Affiliation(s)
- Maranke I Koster
- Department of Dermatology, Charles C. Gates Regenerative Medicine and Stem Cell Biology Program, University of Colorado Denver, Aurora, Colorado 80045, USA.
| |
Collapse
|
28
|
Kim S, Choi IF, Quante JR, Zhang L, Roop DR, Koster MI. p63 directly induces expression of Alox12, a regulator of epidermal barrier formation. Exp Dermatol 2010; 18:1016-21. [PMID: 19555433 DOI: 10.1111/j.1600-0625.2009.00894.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Epidermal development and differentiation are tightly controlled processes that culminate in the formation of the epidermal barrier. A critical regulator of different stages of epidermal development and differentiation is the transcription factor p63. More specifically, we previously demonstrated elsewhere that p63 is required for both the commitment to stratification and the commitment to terminal differentiation. We now demonstrate that DeltaNp63alpha, the predominantly expressed p63 isoform in postnatal epidermis, also plays a role in the final stages of epidermal differentiation, namely the formation of the epidermal barrier. We found that DeltaNp63alpha contributes to epidermal barrier formation by directly inducing expression of ALOX12, a lipoxygenase which contributes to epidermal barrier function. Our data demonstrate that DeltaNp63alpha directly interacts with the promoter of Alox12 in the developing epidermis. Furthermore, we found that the induction of Alox12 expression by DeltaNp63alpha depends on intact p63 binding sites in the Alox12 promoter. Finally, we found that DeltaNp63alpha can induce Alox12 expression only in differentiating keratinocytes, consistent with the role of ALOX12 in epidermal barrier formation.
Collapse
Affiliation(s)
- Soeun Kim
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | | | | | | | | | | |
Collapse
|
29
|
Moretti F, Marinari B, Lo Iacono N, Botti E, Giunta A, Spallone G, Garaffo G, Vernersson-Lindahl E, Merlo G, Mills AA, Ballarò C, Alemà S, Chimenti S, Guerrini L, Costanzo A. A regulatory feedback loop involving p63 and IRF6 links the pathogenesis of 2 genetically different human ectodermal dysplasias. J Clin Invest 2010; 120:1570-7. [PMID: 20424325 DOI: 10.1172/jci40267] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 02/24/2010] [Indexed: 12/19/2022] Open
Abstract
The human congenital syndromes ectrodactyly ectodermal dysplasia-cleft lip/palate syndrome, ankyloblepharon ectodermal dysplasia clefting, and split-hand/foot malformation are all characterized by ectodermal dysplasia, limb malformations, and cleft lip/palate. These phenotypic features are a result of an imbalance between the proliferation and differentiation of precursor cells during development of ectoderm-derived structures. Mutations in the p63 and interferon regulatory factor 6 (IRF6) genes have been found in human patients with these syndromes, consistent with phenotypes. Here, we used human and mouse primary keratinocytes and mouse models to investigate the role of p63 and IRF6 in proliferation and differentiation. We report that the DeltaNp63 isoform of p63 activated transcription of IRF6, and this, in turn, induced proteasome-mediated DeltaNp63 degradation. This feedback regulatory loop allowed keratinocytes to exit the cell cycle, thereby limiting their ability to proliferate. Importantly, mutations in either p63 or IRF6 resulted in disruption of this regulatory loop: p63 mutations causing ectodermal dysplasias were unable to activate IRF6 transcription, and mice with mutated or null p63 showed reduced Irf6 expression in their palate and ectoderm. These results identify what we believe to be a novel mechanism that regulates the proliferation-differentiation balance of keratinocytes essential for palate fusion and skin differentiation and links the pathogenesis of 2 genetically different groups of ectodermal dysplasia syndromes into a common molecular pathway.
Collapse
Affiliation(s)
- Francesca Moretti
- Department of Dermatology, University of Rome Tor Vergata, Rome, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Xia X, Park E, Liu B, Willette-Brown J, Gong W, Wang J, Mitchell D, Fischer SM, Hu Y. Reduction of IKKalpha expression promotes chronic ultraviolet B exposure-induced skin inflammation and carcinogenesis. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 176:2500-8. [PMID: 20304950 DOI: 10.2353/ajpath.2010.091041] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Ultraviolet B light (UVB) is a common cause of human skin cancer. UVB irradiation induces mutations in the tumor suppressor p53 gene as well as chronic inflammation, which are both essential for UVB carcinogenesis. Inhibitor of nuclear factor kappaB kinase-alpha (IKKalpha) plays an important role in maintaining skin homeostasis, and expression of IKKalpha was found to be down-regulated in human and murine skin squamous cell carcinomas. However, the role of IKKalpha in UVB skin carcinogenesis has not been investigated. Thus, here we performed UVB carcinogenesis experiments on Ikkalpha(+/+) and Ikkalpha(+/-) mice. Ikkalpha(+/-) mice were found to develop a twofold greater number of skin tumors than Ikkalpha(+/+) mice after chronic UVB irradiation. In addition, tumor latency was significantly shorter and tumors were bigger in Ikkalpha(+/-) than in Ikkalpha(+/+) mice. At an early stage of carcinogenesis, an increase in UVB-induced p53 mutations as well as macrophage recruitment and mitogenic activity, and a decrease in UVB-induced apoptosis, were detected in Ikkalpha(+/-) compared with those in Ikkalpha(+/+) skin. Also, reduction of IKKalpha levels in keratinocytes up-regulated the expression of monocyte chemoattractant protein-1 (MCP-1/CCL2), TNFalpha, IL-1, and IL-6, and elevated macrophage migration, which might promote macrophage recruitment and inflammation. Therefore, these findings suggest that reduction of IKKalpha expression orchestrates UVB carcinogen, accelerating tumorigenesis.
Collapse
Affiliation(s)
- Xiaojun Xia
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, Texas, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Koster MI, Marinari B, Payne AS, Kantaputra PN, Costanzo A, Roop DR. DeltaNp63 knockdown mice: A mouse model for AEC syndrome. Am J Med Genet A 2010; 149A:1942-7. [PMID: 19681108 DOI: 10.1002/ajmg.a.32794] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Dominant mutations in TP63 cause ankyloblepharon ectodermal dysplasia and clefting (AEC), an ectodermal dysplasia characterized by skin fragility. Since DeltaNp63alpha is the predominantly expressed TP63 isoform in postnatal skin, we hypothesized that mutant DeltaNp63alpha proteins are primarily responsible for skin fragility in AEC patients. We found that mutant DeltaNp63alpha proteins expressed in AEC patients function as dominant-negative molecules, suggesting that the human AEC skin phenotype could be mimicked in mouse skin by downregulating DeltaNp63alpha. Indeed, downregulating DeltaNp63 expression in mouse epidermis caused severe skin erosions, which resembled lesions that develop in AEC patients. In both cases, lesions were characterized by suprabasal epidermal proliferation, delayed terminal differentiation, and basement membrane abnormalities. By failing to provide structural stability to the epidermis, these defects likely contribute to the observed skin fragility. The development of a mouse model for AEC will allow us to further unravel the genetic pathways that are normally regulated by DeltaNp63 and that may be perturbed in AEC patients. Ultimately, these studies will not only contribute to our understanding of the molecular mechanisms that cause skin fragility in AEC patients, but may also result in the identification of targets for novel therapeutic approaches aimed at treating skin erosions. (c) 2009 Wiley-Liss, Inc.
Collapse
Affiliation(s)
- Maranke I Koster
- Department of Dermatology and Charles C. Gates Regenerative Medicine and Stem Cell Biology Program, University of Colorado-Denver, Aurora, CO 80045, USA.
| | | | | | | | | | | |
Collapse
|
32
|
Abstract
The skin functions as a barrier protecting the body from dehydration and environmental insults. This barrier function is mainly provided by the outermost layer of the skin, the epidermis. The epidermis is maintained by epidermal stem cells which reside in the basal layer and which generate daughter cells that move upward toward the surface of the skin. During this journey, keratinocytes undergo a series of biochemical and morphological changes that result in the formation of the various layers of the epidermis. Eventually, these cells turn into the outermost layer of dead cornified cells that are sloughed into the environment. This review summarizes our current understanding of the mechanisms that control proliferation and differentiation of epidermal stem cells, and thus addresses fundamental processes that control epidermal morphogenesis and function.
Collapse
Affiliation(s)
- Maranke I Koster
- Department of Dermatology and Charles C Gates Regenerative Medicine and Stem Cell Biology Program, University of Colorado Denver, Aurora, Colorado 80045, USA.
| |
Collapse
|
33
|
Lopardo T, Lo Iacono N, Marinari B, Giustizieri ML, Cyr DG, Merlo G, Crosti F, Costanzo A, Guerrini L. Claudin-1 is a p63 target gene with a crucial role in epithelial development. PLoS One 2008; 3:e2715. [PMID: 18648642 PMCID: PMC2453228 DOI: 10.1371/journal.pone.0002715] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 06/19/2008] [Indexed: 12/31/2022] Open
Abstract
The epidermis of the skin is a self-renewing, stratified epithelium that functions as the interface between the human body and the outer environment, and acts as a barrier to water loss. Components of intercellular junctions, such as Claudins, are critical to maintain tissue integrity and water retention. p63 is a transcription factor essential for proliferation of stem cells and for stratification in epithelia, mutated in human hereditary syndromes characterized by ectodermal dysplasia. Both p63 and Claudin-1 null mice die within few hours from birth due to dehydration from severe skin abnormalities. These observations suggested the possibility that these two genes might be linked in one regulatory pathway with p63 possibly regulating Claudin-1 expression. Here we show that silencing of ΔNp63 in primary mouse keratinocytes results in a marked down-regulation of Claudin-1 expression (−80%). ΔNp63α binds in vivo to the Claudin-1 promoter and activates both the endogenous Claudin-1 gene and a reporter vector containing a –1.4 Kb promoter fragment of the Claudin-1 gene. Accordingly, Claudin-1 expression was absent in the skin of E15.5 p63 null mice and natural p63 mutant proteins, specifically those found in Ankyloblepharon–Ectodermal dysplasia–Clefting (AEC) patients, were indeed altered in their capacity to regulate Claudin-1 transcription. This correlates with deficient Claudin-1 expression in the epidermis of an AEC patient carrying the I537T p63 mutation. Notably, AEC patients display skin fragility similar to what observed in the epidermis of Claudin-1 and p63 null mice. These findings reinforce the hypothesis that these two genes might be linked in a common regulatory pathway and that Claudin-1 may is an important p63 target gene involved in the pathogenesis of ectodermal dysplasias.
Collapse
Affiliation(s)
- Teresa Lopardo
- Department of Biomolecular Sciences and Biotechnology, University of Milan, Milan, Italy
| | - Nadia Lo Iacono
- Department of Biomolecular Sciences and Biotechnology, University of Milan, Milan, Italy
| | - Barbara Marinari
- Department of Dermatology, University of Rome “Tor Vergata”, Rome, Italy
| | | | - Daniel G. Cyr
- INRS-Institut Armand-Frappier, Laval, Quebec, Canada
| | - Giorgio Merlo
- Dulbecco Telethon Laboratory, Molecular Biotech Center, University of Torino, Torino, Italy
| | | | - Antonio Costanzo
- Department of Dermatology, University of Rome “Tor Vergata”, Rome, Italy
| | - Luisa Guerrini
- Department of Biomolecular Sciences and Biotechnology, University of Milan, Milan, Italy
- * E-mail:
| |
Collapse
|