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DMBA/TPA treatment is necessary for BCC formation from patched deficient epidermal cells in Ptch(flox/flox)CD4Cre(+/-) mice. J Invest Dermatol 2014; 134:2620-2629. [PMID: 24662765 DOI: 10.1038/jid.2014.157] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 02/20/2014] [Accepted: 02/28/2014] [Indexed: 12/17/2022]
Abstract
The development of basal cell carcinoma (BCC), the most frequently diagnosed tumor among persons with European ancestry, is closely linked to mutations in the Hedgehog (Hh) receptor and tumor suppressor Patched1 (Ptch). Using Ptch(flox/flox)CD4Cre(+/-) mice, in which Ptch was ablated in CD4Cre-expressing cells, we demonstrate that the targeted cells can give rise to BCC after treatment with DMBA (7,12-dimethylbenz(a)anthracene)/TPA (12-O-tetradecanoylphorbol-13-acetate), but not after wounding of the skin. In addition, in this model, BCC are not caused by malfunctioning of Ptch-deficient T cells, as BCC did not develop when bone marrow (BM) of Ptch(flox/flox)CD4Cre(+/-) mice was transplanted into Ptch wild-type mice. Instead, lineage-tracing experiments and flow cytometric analyses suggest that the tumors are initiated from rare Ptch-deficient stem cell-like cells of the epidermis that express CD4. As DMBA/TPA is a prerequisite for BCC development in this model, the initiated cells need a second stimulus for expansion and tumor formation. However, in contrast to papilloma, this stimulus seems to be unrelated to alterations in the Ras signaling cascade. Together, these data suggest that biallelic loss of Ptch in CD4(+) cells does not suffice for BCC formation and that BCC formation requires a second so far unknown event, at least in the Ptch(flox/flox)CD4Cre(+/-) BCC mouse model.
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152
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Transplantation of the LGR6+ Epithelial Stem Cell into Full-Thickness Cutaneous Wounds Results in Enhanced Healing, Nascent Hair Follicle Development, and Augmentation of Angiogenic Analytes. Plast Reconstr Surg 2014; 133:579-590. [DOI: 10.1097/prs.0000000000000075] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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153
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Lu C, Fuchs E. Sweat gland progenitors in development, homeostasis, and wound repair. Cold Spring Harb Perspect Med 2014; 4:4/2/a015222. [PMID: 24492848 DOI: 10.1101/cshperspect.a015222] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The human body is covered with several million sweat glands. These tiny coiled tubular skin appendages produce the sweat that is our primary source of cooling and hydration of the skin. Numerous studies have been published on their morphology and physiology. Until recently, however, little was known about how glandular skin maintains homeostasis and repairs itself after tissue injury. Here, we provide a brief overview of sweat gland biology, including newly identified reservoirs of stem cells in glandular skin and their activation in response to different types of injuries. Finally, we discuss how the genetics and biology of glandular skin has advanced our knowledge of human disorders associated with altered sweat gland activity.
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Affiliation(s)
- Catherine Lu
- Laboratory of Mammalian Cell Biology and Development, The Rockefeller University, New York, New York 10065
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154
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Rishikaysh P, Dev K, Diaz D, Qureshi WMS, Filip S, Mokry J. Signaling involved in hair follicle morphogenesis and development. Int J Mol Sci 2014; 15:1647-70. [PMID: 24451143 PMCID: PMC3907891 DOI: 10.3390/ijms15011647] [Citation(s) in RCA: 239] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Revised: 10/21/2013] [Accepted: 10/22/2013] [Indexed: 12/17/2022] Open
Abstract
Hair follicle morphogenesis depends on Wnt, Shh, Notch, BMP and other signaling pathways interplay between epithelial and mesenchymal cells. The Wnt pathway plays an essential role during hair follicle induction, Shh is involved in morphogenesis and late stage differentiation, Notch signaling determines stem cell fate while BMP is involved in cellular differentiation. The Wnt pathway is considered to be the master regulator during hair follicle morphogenesis. Wnt signaling proceeds through EDA/EDAR/NF-κB signaling. NF-κB regulates the Wnt pathway and acts as a signal mediator by upregulating the expression of Shh ligand. Signal crosstalk between epithelial and mesenchymal cells takes place mainly through primary cilia. Primary cilia formation is initiated with epithelial laminin-511 interaction with dermal β-1 integrin, which also upregulates expression of downstream effectors of Shh pathway in dermal lineage. PDGF signal transduction essential for crosstalk is mediated through epithelial PDGF-A and PDGFRα expressed on the primary cilia. Dermal Shh and PDGF signaling up-regulates dermal noggin expression; noggin is a potent inhibitor of BMP signaling which helps in counteracting BMP mediated β-catenin inhibition. This interplay of signaling between the epithelial and dermal lineage helps in epithelial Shh signal amplification. The dermal Wnt pathway helps in upregulation of epithelial Notch expression. Dysregulation of these pathways leads to certain abnormalities and in some cases even tumor outgrowth.
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Affiliation(s)
- Pisal Rishikaysh
- Department of Histology and Embryology, Medical Faculty in Hradec Kralove, Charles University in Prague, Simkova 870, 500 38 Hradec Kralove, Czech Republic.
| | - Kapil Dev
- Department of Histology and Embryology, Medical Faculty in Hradec Kralove, Charles University in Prague, Simkova 870, 500 38 Hradec Kralove, Czech Republic.
| | - Daniel Diaz
- Department of Histology and Embryology, Medical Faculty in Hradec Kralove, Charles University in Prague, Simkova 870, 500 38 Hradec Kralove, Czech Republic.
| | - Wasay Mohiuddin Shaikh Qureshi
- Department of Histology and Embryology, Medical Faculty in Hradec Kralove, Charles University in Prague, Simkova 870, 500 38 Hradec Kralove, Czech Republic.
| | - Stanislav Filip
- Department of Oncology and Radiotherapy, Medical Faculty in Hradec Kralove, Charles University in Prague, Simkova 870, 500 38 Hradec Kralove, Czech Republic.
| | - Jaroslav Mokry
- Department of Histology and Embryology, Medical Faculty in Hradec Kralove, Charles University in Prague, Simkova 870, 500 38 Hradec Kralove, Czech Republic.
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155
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Abstract
Cutaneous wound healing assay is important to address many key questions including (1) migration ability of different cells; (2) communication between the different cell types such as keratinocytes, fibroblasts, and immune cells; (3) understanding the cell-autonomous and non-cell-autonomous function(s) of the different cells; and (4) gene regulation in healing processes. Wound healing studies can be used to test new treatment modalities, function of new drugs/compounds, and stem cell-based therapies on the different stages of healing and for accelerating wound healing in patients with compromised healing. In this chapter, we have described a simple step-by-step protocol to generate full-thickness cutaneous wounds in the dorsal skin of mice, followed by collecting the post-wounding biopsied materials on specific days for histological and immunohistochemical analyses and for RNA and protein extractions.
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Affiliation(s)
- Gitali Ganguli-Indra
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, 1601 SW Jefferson str, Corvallis, OR, 97331, USA,
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156
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Abstract
The skin is the first line of defense against dehydration and external environmental aggressions. It constantly renews itself throughout adult life mainly due to the activity of tissue-specific stem cells. In this review, we discuss fundamental characteristics of different stem cell populations within the skin and how they are able to contribute to normal skin homeostasis. We also examine the most recent results regarding the cell-intrinsic and -extrinsic components of the stem cell niche within the adult skin epithelium. Finally, we address the recent efforts to understand how abnormal regulation of stem cell activity contributes to the initiation and progression of skin-associated cancers.
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Affiliation(s)
| | - Valerie Horsley
- Department of Molecular, Cell and Developmental Biology, Yale University, New Haven, Connecticut, USA.
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157
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Abstract
Lineage tracing involves labeling cells to track their subsequent behavior within the normal tissue environment. The advent of genetic lineage tracing and cell proliferation assays, together with high resolution three-dimensional (3D) imaging and quantitative methods to infer cell behavior from lineage-tracing data, has transformed our understanding of murine epidermal stem and progenitor cells. Here, we review recent insights that reveal how a progenitor cell population maintains interfollicular epidermis, whereas stem cells, quiescent under homeostatic conditions, are mobilized in response to wounding. We discuss progress in understanding how the various stem cell populations of the hair follicle sustain this complex and highly dynamic structure, and recent analysis of stem cells in sweat and sebaceous glands. The extent to which insights from mouse studies can be applied to human epidermis is also considered.
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Affiliation(s)
- Maria P Alcolea
- MRC Cancer Unit, University of Cambridge, Cambridge CB2 0XZ, United Kingdom
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158
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Affiliation(s)
- Julia Frede
- MRC Cancer Unit, University of Cambridge, Hutchison-MRC Research Centre, Box 197, Cambridge Biomedical Campus, Cambridge CB2 0XZ, UK
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159
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Rompolas P, Greco V. Stem cell dynamics in the hair follicle niche. Semin Cell Dev Biol 2013; 25-26:34-42. [PMID: 24361866 DOI: 10.1016/j.semcdb.2013.12.005] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 11/27/2013] [Accepted: 12/11/2013] [Indexed: 12/17/2022]
Abstract
Hair follicles are appendages of the mammalian skin that have the ability to periodically and stereotypically regenerate in order to continuously produce new hair over our lifetime. The ability of the hair follicle to regenerate is due to the presence of stem cells that along with other cell populations and non-cellular components, including molecular signals and extracellular material, make up a niche microenvironment. Mounting evidence suggests that the niche is critical for regulating stem cell behavior and thus the process of regeneration. Here, we review the literature concerning past and current studies that have utilized mouse genetic models, combined with other approaches to dissect the molecular and cellular composition of the hair follicle niche. We also discuss our current understanding of how stem cells operate within the niche during the process of tissue regeneration and the factors that regulate their behavior.
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Affiliation(s)
- Panteleimon Rompolas
- Department of Genetics, Department of Dermatology, Yale Stem Cell Center, Yale Cancer Center, Yale School of Medicine, New Haven, CT 06510, USA.
| | - Valentina Greco
- Department of Genetics, Department of Dermatology, Yale Stem Cell Center, Yale Cancer Center, Yale School of Medicine, New Haven, CT 06510, USA.
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160
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Lin LM, Ricucci D, Huang GTJ. Regeneration of the dentine-pulp complex with revitalization/revascularization therapy: challenges and hopes. Int Endod J 2013; 47:713-24. [PMID: 24330275 DOI: 10.1111/iej.12210] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Accepted: 11/01/2013] [Indexed: 12/12/2022]
Abstract
The concept of regenerative endodontics has gained much attention in clinical endodontics in the past decade. One aspect of this discipline is the application of revitalization/revascularization therapies for infected and/or necrotic immature pulps in permanent teeth. Following the publication of a case report (Iwaya et al. ), investigators have been rigorously examining the types of tissues formed in the canals as well as exploring strategies to regenerate the pulp-dentine complex in revitalized teeth. This review will provide an update on the types of tissues generated in the canals after revitalization/revascularization therapy in both animal and human studies. The understanding of the role of stem cells and microenvironment in the process of wound healing resulting in either regeneration or repair will be thoroughly discussed. Stem cells and microenvironmental cues introduced into the canal during revitalization/revascularization procedures will be examined. In addition, requirement of a sterile microenvironment in the canal and vital tissue generation in revitalization/revascularization therapy will be emphasized. The challenges that we face and the hopes that we have in revitalization/revascularization therapy for regenerative endodontics will be presented.
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Affiliation(s)
- L M Lin
- Department of Endodontics, New York University College of Dentistry, New York, NY, USA
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161
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Whyte JL, Smith AA, Liu B, Manzano WR, Evans ND, Dhamdhere GR, Fang MY, Chang HY, Oro AE, Helms JA. Augmenting endogenous Wnt signaling improves skin wound healing. PLoS One 2013; 8:e76883. [PMID: 24204695 PMCID: PMC3799989 DOI: 10.1371/journal.pone.0076883] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 08/28/2013] [Indexed: 11/18/2022] Open
Abstract
Wnt signaling is required for both the development and homeostasis of the skin, yet its contribution to skin wound repair remains controversial. By employing Axin2LacZ/+ reporter mice we evaluated the spatial and temporal distribution patterns of Wnt responsive cells, and found that the pattern of Wnt responsiveness varies with the hair cycle, and correlates with wound healing potential. Using Axin2LacZ/LacZ mice and an ear wound model, we demonstrate that amplified Wnt signaling leads to improved healing. Utilizing a biochemical approach that mimics the amplified Wnt response of Axin2LacZ/LacZ mice, we show that topical application of liposomal Wnt3a to a non-healing wound enhances endogenous Wnt signaling, and results in better skin wound healing. Given the importance of Wnt signaling in the maintenance and repair of skin, liposomal Wnt3a may have widespread application in clinical practice.
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Affiliation(s)
- Jemima L. Whyte
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Andrew A. Smith
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Bo Liu
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Wilfred R. Manzano
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Nick D. Evans
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Girija R. Dhamdhere
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Mark Y. Fang
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
| | - Howard Y. Chang
- Department of Dermatology, Stanford School of Medicine, Stanford, California, United States of America
- Howard Hughes Medical Institute, Stanford, California, United States of America
| | - Anthony E. Oro
- Department of Dermatology, Stanford School of Medicine, Stanford, California, United States of America
| | - Jill A. Helms
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, California, United States of America
- * E-mail:
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162
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Bone morphogenetic protein signaling suppresses wound-induced skin repair by inhibiting keratinocyte proliferation and migration. J Invest Dermatol 2013; 134:827-837. [PMID: 24126843 PMCID: PMC3945401 DOI: 10.1038/jid.2013.419] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 09/02/2013] [Accepted: 09/16/2013] [Indexed: 12/29/2022]
Abstract
Bone morphogenetic protein (BMP) signalling plays a key role in the control of skin development and postnatal remodelling by regulating keratinocyte proliferation, differentiation and apoptosis. To study the role of BMPs in wound-induced epidermal repair, we used transgenic mice overexpressing the BMP downstream component Smad1 under the control of a K14 promoter as an in vivo model, as well as ex vivo and in vitro assays. K14-caSmad1 mice exhibited retarded wound healing associated with significant inhibition of proliferation and increased apoptosis in healing wound epithelium. Furthermore, microarray and qRT-PCR analyses revealed decreased expression of a number of cytoskeletal/cell motility-associated genes including wound-associated keratins (Krt16, Krt17) and Myo5a, in the epidermis of K14-caSmad1 mice versus wild-type controls during wound healing. BMP treatment significantly inhibited keratinocyte migration ex vivo, and primary keratinocytes of K14-caSmad1 mice showed retarded migration compared to wild-type controls. Finally, siRNA-mediated silencing of Bmpr-1B in primary mouse keratinocytes accelerated cell migration and was associated with increased expression of Krt16, Krt17 and Myo5a compared to controls. Thus, this study demonstrates that BMPs inhibit keratinocyte proliferation, cytoskeletal organization and migration in regenerating skin epithelium during wound healing, and raises a possibility for using BMP antagonists for the management of chronic wounds.
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163
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A novel model of surgical injury in adult rat kidney: a "pouch model". Sci Rep 2013; 3:2890. [PMID: 24100472 PMCID: PMC3792422 DOI: 10.1038/srep02890] [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: 03/25/2013] [Accepted: 09/09/2013] [Indexed: 11/16/2022] Open
Abstract
Regenerative mechanisms after surgical injury have been studied in many organs but not in the kidney. Studying surgical injury may provide new insights into mechanisms of kidney regeneration. In rodent models, extrarenal tissues adhere to surgical kidney wound and interfere with healing. We hypothesized that this can be prevented by wrapping injured kidney in a plastic pouch. Adult rats tolerated 5/6 nephrectomy with pouch application well. Histological analysis demonstrates that application of the pouch effectively prevented formation of adhesions and induced characteristic wound healing manifested by formation of granulation tissue. Additionally, selected tubules of the wounded kidney extended into the granulation tissue forming branching tubular epithelial outgrowths (TEOs) without terminal differentiation. Tubular regeneration outside of renal parenchyma was not previously observed, and suggests previously unrecognized capacity for regeneration. Our model provides a novel approach to study kidney wound healing.
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164
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Fractional Skin Harvesting: Autologous Skin Grafting without Donor-site Morbidity. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2013; 1:e47. [PMID: 25289241 PMCID: PMC4174164 DOI: 10.1097/gox.0b013e3182a85a36] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 07/18/2013] [Indexed: 11/26/2022]
Abstract
Background: Conventional autologous skin grafts are associated with significant donor-site morbidity. This study was conducted to determine feasibility, safety, and efficacy of a new strategy for skin grafting based on harvesting small columns of full-thickness skin with minimal donor-site morbidity. Methods: The swine model was used for this study. Hundreds of full-thickness columns of skin tissue (~700 µm diameter) were harvested using a custom-made harvesting device, and then applied directly to excisional skin wounds. Healing in donor and graft sites was evaluated over 3 months by digital photographic measurement of wound size and blinded, computer-aided evaluation of histological features and compared with control wounds that healed by secondary intention or with conventional split-thickness skin grafts (STSG). Results: After harvesting hundreds of skin columns, the donor sites healed rapidly without scarring. These sites reepithelialized within days and were grossly and histologically indistinguishable from normal skin within 7 weeks. By contrast, STSG donor sites required 2 weeks for reepithelialization and retained scar-like characteristics in epidermal and dermal architecture throughout the experiment. Wounds grafted with skin columns resulted in accelerated reepithelialization compared with ungrafted wounds while avoiding the “fish-net” patterning caused by STSG. Conclusion: Full-thickness columns of skin can be harvested in large quantities with negligible long-term donor-site morbidity, and these columns can be applied directly to skin wounds to enhance wound healing.
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165
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166
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EGFR-ras-raf signaling in epidermal stem cells: roles in hair follicle development, regeneration, tissue remodeling and epidermal cancers. Int J Mol Sci 2013; 14:19361-84. [PMID: 24071938 PMCID: PMC3821561 DOI: 10.3390/ijms141019361] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/12/2013] [Accepted: 09/17/2013] [Indexed: 12/19/2022] Open
Abstract
The mammalian skin is the largest organ of the body and its outermost layer, the epidermis, undergoes dynamic lifetime renewal through the activity of somatic stem cell populations. The EGFR-Ras-Raf pathway has a well-described role in skin development and tumor formation. While research mainly focuses on its role in cutaneous tumor initiation and maintenance, much less is known about Ras signaling in the epidermal stem cells, which are the main targets of skin carcinogenesis. In this review, we briefly discuss the properties of the epidermal stem cells and review the role of EGFR-Ras-Raf signaling in keratinocyte stem cells during homeostatic and pathological conditions.
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167
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Solanas G, Benitah SA. Regenerating the skin: a task for the heterogeneous stem cell pool and surrounding niche. Nat Rev Mol Cell Biol 2013; 14:737-48. [DOI: 10.1038/nrm3675] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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168
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Baik HS, Park J, Lee KJ, Chung C. Local application of periodontal ligament stromal cells promotes soft tissue regeneration. Oral Dis 2013; 20:574-81. [PMID: 24112808 DOI: 10.1111/odi.12175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 07/11/2013] [Accepted: 08/04/2013] [Indexed: 01/07/2023]
Abstract
OBJECTIVES To test the potential stimulatory effect of local application of periodontal ligament (PDL) stromal cells on soft tissue regeneration. MATERIALS AND METHODS Fluorescently labeled PDL cells outgrown from extracted human premolars or phosphate-buffered saline were locally injected to the cutaneous wounds created on mice. Soft tissue regeneration was evaluated for 14 days using photographs and histomorphometry. PDL cell engraftment was tracked with confocal microscopy. To detect the paracrine effect of the PDL cells on soft tissue regeneration, PDL cell-conditioned medium (CM) was evaluated for the concentration of secretory factors, transforming growth factor-beta 1 (TGFβ1). The effect of PDL CM on the proliferation and migration of dermal fibroblast and keratinocyte was tested using MTT assay and migration assay. RESULTS The application of PDL cells significantly promoted soft tissue regeneration compared with the application of PBS. Self-replicating PDL cells were engrafted into the hair follicles of the host tissue. Dermal fibroblast proliferation and keratinocyte migration were significantly enhanced by the treatment with PDL CM. Physiologically significant amount of TGFβ1 was secreted from PDL cells into the CM. CONCLUSION Local injection of PDL cells promoted soft tissue regeneration in part by the enhancement of fibroblast proliferation and keratinocyte migration through a paracrine mechanism.
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Affiliation(s)
- H S Baik
- Department of Orthodontics, Collage of Dentistry, Yonsei University, Seoul, Korea; Institute of Craniofacial Deformity, Yonsei University, Seoul, Korea
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169
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Ceelen W, Pattyn P, Mareel M. Surgery, wound healing, and metastasis: recent insights and clinical implications. Crit Rev Oncol Hematol 2013; 89:16-26. [PMID: 23958676 DOI: 10.1016/j.critrevonc.2013.07.008] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 06/15/2013] [Accepted: 07/18/2013] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Surgery-induced acceleration of tumour growth has been observed since several centuries. METHODS We reviewed recent insights from in vitro data, animal experimentation, and clinical studies on how surgery-induced wound healing or resection of a primary cancer influences the tumour-host ecosystem in patients harbouring minimal residual or metastatic disease. RESULTS Most of the growth factors, chemokines, and cytokines orchestrating surgical wound healing promote tumour growth, invasion, or angiogenesis. In addition, resection of a primary tumour may accelerate synchronous metastatic growth. In the clinical setting, indirect evidence supports the relevance of the above findings. Randomized clinical trials are underway comparing resection versus observation in metastatic breast and colon cancer with asymptomatic primary tumours. CONCLUSIONS In depth knowledge of how surgical intervention alters the tumour-host-metastasis communicating ecosystems could have important implications for clinical decision making in patients with synchronous metastatic disease and for the design and timing of multimodality treatment strategies.
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Affiliation(s)
- Wim Ceelen
- Department of of Surgery, Ghent University Hospital, B-9000 Ghent, Belgium.
| | - Piet Pattyn
- Department of of Surgery, Ghent University Hospital, B-9000 Ghent, Belgium
| | - Marc Mareel
- Department of Radiotherapy and Experimental Cancer Research, Ghent University Hospital, B-9000 Ghent, Belgium
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170
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Page ME, Lombard P, Ng F, Göttgens B, Jensen KB. The epidermis comprises autonomous compartments maintained by distinct stem cell populations. Cell Stem Cell 2013; 13:471-82. [PMID: 23954751 PMCID: PMC3793873 DOI: 10.1016/j.stem.2013.07.010] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 06/18/2013] [Accepted: 07/16/2013] [Indexed: 12/14/2022]
Abstract
The complex anatomy of the epidermis contains multiple adult stem cell populations, but the extent to which they functionally overlap during homeostasis, wound healing, and tumor initiation remains poorly defined. Here, we demonstrate that Lrig1(+ve) cells are highly proliferative epidermal stem cells. Long-term clonal analysis reveals that Lrig1(+ve) cells maintain the upper pilosebaceous unit, containing the infundibulum and sebaceous gland as independent compartments, but contribute to neither the hair follicle nor the interfollicular epidermis, which are maintained by distinct stem cell populations. In contrast, upon wounding, stem cell progeny from multiple compartments acquire lineage plasticity and make permanent contributions to regenerating tissue. We further show that oncogene activation in Lrig1(+ve) cells drives hyperplasia but requires auxiliary stimuli for tumor formation. In summary, our data demonstrate that epidermal stem cells are lineage restricted during homeostasis and suggest that compartmentalization may constitute a conserved mechanism underlying epithelial tissue maintenance.
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Affiliation(s)
- Mahalia E Page
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, Tennis Court Road, CB2 1QR Cambridge, UK; Department of Oncology, University of Cambridge, CB2 0QQ Cambridge, UK
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171
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Makarem M, Kannan N, Nguyen LV, Knapp DJHF, Balani S, Prater MD, Stingl J, Raouf A, Nemirovsky O, Eirew P, Eaves CJ. Developmental changes in the in vitro activated regenerative activity of primitive mammary epithelial cells. PLoS Biol 2013; 11:e1001630. [PMID: 23966837 PMCID: PMC3742452 DOI: 10.1371/journal.pbio.1001630] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 07/03/2013] [Indexed: 01/04/2023] Open
Abstract
Mouse fetal mammary cells display greater regenerative activity than do adult mammary cells when stimulated to proliferate in a new system that supports the production of transplantable mammary stem cells ex vivo. Many normal adult tissues contain rare stem cells with extensive self-maintaining regenerative potential. During development, the stem cells of the hematopoietic and neural systems undergo intrinsically specified changes in their self-renewal potential. In the mouse, mammary stem cells with transplantable regenerative activity are first detectable a few days before birth. They share some phenotypic properties with their adult counterparts but are enriched in a subpopulation that displays a distinct gene expression profile. Here we show that fetal mammary epithelial cells have a greater direct and inducible growth potential than their adult counterparts. The latter feature is revealed in a novel culture system that enables large numbers of in vitro clonogenic progenitors as well as mammary stem cells with serially transplantable activity to be produced within 7 days from single fetal or adult input cells. We further show that these responses are highly dependent on novel factors produced by fibroblasts. These findings provide new avenues for elucidating mechanisms that regulate normal mammary epithelial stem cell properties at the single-cell level, how these change during development, and how their perturbation may contribute to transformation. Many adult tissues are maintained by a rare subset of undifferentiated stem cells that can self-renew and give rise to specialized daughter cells that have a more limited regenerative ability. The recent identification of cells in the fetal and adult mammary gland that display the properties of stem cells provides a foundation for investigating their self-renewal and differentiation control. We now show that these stem cell properties can be elicited from single mouse mammary cells placed in 3D cultures if novel factors produced by fibroblasts are present. Moreover, a comparison of the clonal outputs of fetal and adult mammary cells in this in vitro system shows that the fetal mammary cells have superior regenerative activity relative to their adult counterparts. The ability to activate and quantify the regenerative capacity of single mouse mammary epithelial cells in vitro sets the stage for further investigations of the timing and mechanisms that alter their stem cell properties during development, the potential relevance of these events to other normal epithelial tissues, and how these processes might be involved in the genesis of breast cancer.
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Affiliation(s)
- Maisam Makarem
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Nagarajan Kannan
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Long V. Nguyen
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - David J. H. F. Knapp
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Sneha Balani
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Michael D. Prater
- Cancer Research UK Cambridge Research Institute, Li Ka Shing Centre, Cambridge, United Kingdom
| | - John Stingl
- Cancer Research UK Cambridge Research Institute, Li Ka Shing Centre, Cambridge, United Kingdom
| | - Afshin Raouf
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
- Department of Immunology and The Regenerative Medicine Program, Manitoba Institute of Cell Biology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Oksana Nemirovsky
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Peter Eirew
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Connie J. Eaves
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
- Departments of Medical Genetics, Medicine, and Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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172
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Abstract
Melanocyte stem cells differ greatly from melanoma stem cells; the former provide pigmented cells during normal tissue homeostasis and repair, and the latter play an active role in a lethal form of cancer. These 2 cell types share several features and can be studied by similar methods. Aspects held in common by both melanocyte stem cells and melanoma stem cells include their expression of shared biochemical markers, a system of similar molecular signals necessary for their maintenance, and a requirement for an ideal niche microenvironment for providing these factors. This review provides a perspective of both these cell types and discusses potential models of stem cell growth and propagation. Recent findings provide a strong foundation for the development of new therapeutics directed at isolating and manipulating melanocyte stem cells for tissue engineering or at targeting and eradicating melanoma specifically, while sparing nontumor cells.
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Affiliation(s)
- Deborah Lang
- Department of Medicine, Section of Dermatology, University of Chicago, Pritzker School of Medicine, MC 5067, Chicago, IL 60637, USA.
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173
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Abstract
Adult animals rely on populations of stem cells to ensure organ function throughout their lifetime. Stem cells are governed by signals from stem cell niches, and much is known about how single niches promote stemness and direct stem cell behavior. However, most organs contain a multitude of stem cell-niche units, which are often distributed across the entire expanse of the tissue. Beyond the biology of individual stem cell-niche interactions, the next challenge is to uncover the tissue-level processes that orchestrate spatial control of stem-based renewal, repair, and remodeling throughout a whole organ. Here we examine what is known about higher order mechanisms for interniche coordination in epithelial organs, whose simple geometry offers a promising entry point for understanding the regulation of niche number, distribution, and activity. We also consider the potential existence of stem cell territories and how tissue architecture may influence niche coordination.
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Affiliation(s)
- Lucy Erin O'Brien
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305;
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174
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Blanpain C, Simons BD. Unravelling stem cell dynamics by lineage tracing. Nat Rev Mol Cell Biol 2013; 14:489-502. [PMID: 23860235 DOI: 10.1038/nrm3625] [Citation(s) in RCA: 184] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
During embryonic and postnatal development, the different cells types that form adult tissues must be generated and specified in a precise temporal manner. During adult life, most tissues undergo constant renewal to maintain homeostasis. Lineage-tracing and genetic labelling technologies are beginning to shed light on the mechanisms and dynamics of stem and progenitor cell fate determination during development, tissue maintenance and repair, as well as their dysregulation in tumour formation. Statistical approaches, based on proliferation assays and clonal fate analyses, provide quantitative insights into cell kinetics and fate behaviour. These are powerful techniques to address new questions and paradigms in transgenic mouse models and other model systems.
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Affiliation(s)
- Cédric Blanpain
- Université Libre de Bruxelles, Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire (IRIBHM), Brussels, Belgium.
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175
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Senoo M. Epidermal Stem Cells in Homeostasis and Wound Repair of the Skin. Adv Wound Care (New Rochelle) 2013; 2:273-282. [PMID: 24527349 DOI: 10.1089/wound.2012.0372] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Indexed: 12/17/2022] Open
Abstract
SIGNIFICANCE The skin interfollicular epidermis (IFE) is an organism's first line of defense against a harmful environment and physical damage. During homeostasis and wound repair, the IFE is rejuvenated constantly by IFE stem cells (SCs) that are capable of both proliferation and differentiation. However, the identity and behavior of IFE SCs remain controversial. RECENT ADVANCES Two opposing theories exist regarding homeostasis of the IFE. On the basis of morphological and proliferative characteristics, one posits that the IFE is composed of a discrete epidermal proliferative unit comprised of ∼10 transit-amplifying (TA) cells and a centrally located SC in the basal layer. The other suggests that homeostasis of the IFE is maintained by a single progenitor population in the basal layer. A recent study has challenged these two apparently distinct models and demonstrated that the basal layer of the IFE contains both SCs and TA cells, which make distinct contributions to tissue homeostasis and repair. Moreover, phosphorylation levels of the transcription factor p63, the master regulator of the proliferative potential of epidermal SCs, can be used to distinguish self-renewing SCs from TA cells with more limited proliferative potential. CRITICAL ISSUES As technologies advance, IFE SCs can be identified at a single-cell level. Refinements of their identification and characterization are critical, not only for SC biology but also for the development of novel clinical applications. FUTURE DIRECTIONS Understanding the signaling pathways that control self-renewal and differentiation of IFE SCs will aid in developing novel cell-based therapeutics targeting degenerative epidermal diseases and wound repair.
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Affiliation(s)
- Makoto Senoo
- Institute for Regenerative Medicine, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania
- Department of Animal Biology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania
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176
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Kamel RA, Ong JF, Eriksson E, Junker JPE, Caterson EJ. Tissue engineering of skin. J Am Coll Surg 2013; 217:533-55. [PMID: 23816384 DOI: 10.1016/j.jamcollsurg.2013.03.027] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 03/15/2013] [Accepted: 03/18/2013] [Indexed: 11/18/2022]
Affiliation(s)
- Rami A Kamel
- Division of Plastic Surgery, Brigham and Women's Surgery, Harvard Medical School, Boston, MA 02115, USA
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177
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Makarem M, Spike BT, Dravis C, Kannan N, Wahl GM, Eaves CJ. Stem cells and the developing mammary gland. J Mammary Gland Biol Neoplasia 2013; 18:209-19. [PMID: 23624881 PMCID: PMC4161372 DOI: 10.1007/s10911-013-9284-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 04/16/2013] [Indexed: 12/13/2022] Open
Abstract
The mammary gland undergoes dynamic changes throughout life. In the mouse, these begin with initial morphogenesis of the gland in the mid-gestation embryo followed by hormonally regulated changes during puberty and later in adulthood. The adult mammary gland contains a hierarchy of cell types with varying potentials for self-maintenance and differentiation. These include cells able to produce complete, functional mammary glands in vivo and that contain daughter cells with the same remarkable regenerative potential, as well as cells with more limited clonogenic activity in vitro. Here we review how applying in vitro and in vivo methods for quantifying these cells in adult mammary tissue to fetal mammary cells has enabled the first cells fulfilling the functional criteria of transplantable, isolated mammary stem cells to be identified a few days before birth. Thereafter, the number of these cells increases rapidly. Populations containing these fetal stem cells display growth and gene expression programs that differ from their adult counterparts but share signatures characteristic of certain types of breast cancer. Such observations reinforce growing evidence of important differences between tissue-specific fetal and adult cells with stem cell properties and emphasize the merits of investigating their molecular basis.
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Affiliation(s)
- Maisam Makarem
- Terry Fox Laboratory, British Columbia Cancer Agency, 675 West 10th Avenue, Vancouver, BC V5Z 1L3, Canada
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178
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Epidermal stem cells in orthopaedic regenerative medicine. Int J Mol Sci 2013; 14:11626-42. [PMID: 23727934 PMCID: PMC3709750 DOI: 10.3390/ijms140611626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 05/15/2013] [Accepted: 05/20/2013] [Indexed: 01/01/2023] Open
Abstract
In the last decade, great advances have been made in epidermal stem cell studies at the cellular and molecular level. These studies reported various subpopulations and differentiations existing in the epidermal stem cell. Although controversies and unknown issues remain, epidermal stem cells possess an immune-privileged property in transplantation together with easy accessibility, which is favorable for future clinical application. In this review, we will summarize the biological characteristics of epidermal stem cells, and their potential in orthopedic regenerative medicine. Epidermal stem cells play a critical role via cell replacement, and demonstrate significant translational potential in the treatment of orthopedic injuries and diseases, including treatment for wound healing, peripheral nerve and spinal cord injury, and even muscle and bone remodeling.
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179
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Epidermal development in mammals: key regulators, signals from beneath, and stem cells. Int J Mol Sci 2013; 14:10869-95. [PMID: 23708093 PMCID: PMC3709707 DOI: 10.3390/ijms140610869] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 04/22/2013] [Accepted: 04/23/2013] [Indexed: 12/23/2022] Open
Abstract
Epidermis is one of the best-studied tissues in mammals that contain types of stem cells. Outstanding works in recent years have shed great light on behaviors of different epidermal stem cell populations in the homeostasis and regeneration of the epidermis as well as hair follicles. Also, the molecular mechanisms governing these stem cells are being elucidated, from genetic to epigenetic levels. Compared with the explicit knowledge about adult skin, embryonic development of the epidermis, especially the early period, still needs exploration. Furthermore, stem cells in the embryonic epidermis are largely unstudied or ambiguously depicted. In this review, we will summarize and discuss the process of embryonic epidermal development, with focuses on some key molecular regulators and the role of the sub-epidermal mesenchyme. We will also try to trace adult epidermal stem cell populations back to embryonic development. In addition, we will comment on in vitro derivation of epidermal lineages from ES cells and iPS cells.
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180
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Abstract
Primary human oral epithelial cells are readily available and have been recently employed for tissue engineering. These cells are currently being widely utilized in multiple research efforts, ranging from the study of oral biology, mucosal immunity, and carcinogenesis to stem cell biology and tissue engineering. This chapter describes step-by-step protocols for the successful isolation and culture of human oral epithelial cells and fibroblasts, and techniques for their use in two-dimensional and three-dimensional culture systems. The described methods will enable to generate reconstituted tissues that resemble epithelial like structures in vitro, which can recapitulate some of the key features of the oral epithelium in vivo.
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181
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Sun X, Fu X, Han W, Zhao M, Chalmers L. Epidermal stem cells: an update on their potential in regenerative medicine. Expert Opin Biol Ther 2013; 13:901-10. [DOI: 10.1517/14712598.2013.776036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Xiaoyan Sun
- Wound Healing and Cell Biology Laboratory, Institute of Basic Medical Science, Trauma Center of Postgraduate Medical School, Chinese PLA General Hospital,
28 Fu Xing Road, Beijing 100853, P. R. China ;
- Department of Dermatology, UC Davis School of Medicine,
Suite 1630, 2921 Stockton Blvd, Sacramento, CA 95817, USA
- Department of Ophthalmology,
Sacramento, CA, USA
- Institute for Regenerative Cures, UC Davis School of Medicine,
Suite 1630, 2921 Stockton Blvd, Sacramento, CA 95817, USA
| | - Xiaobing Fu
- Wound Healing and Cell Biology Laboratory, Institute of Basic Medical Science, Trauma Center of Postgraduate Medical School, Chinese PLA General Hospital,
28 Fu Xing Road, Beijing 100853, P. R. China ;
| | - Weidong Han
- Wound Healing and Cell Biology Laboratory, Institute of Basic Medical Science, Trauma Center of Postgraduate Medical School, Chinese PLA General Hospital,
28 Fu Xing Road, Beijing 100853, P. R. China ;
| | - Min Zhao
- Department of Dermatology, UC Davis School of Medicine,
Suite 1630, 2921 Stockton Blvd, Sacramento, CA 95817, USA
- Department of Ophthalmology,
Sacramento, CA, USA
- Institute for Regenerative Cures, UC Davis School of Medicine,
Suite 1630, 2921 Stockton Blvd, Sacramento, CA 95817, USA
| | - Laura Chalmers
- Department of Dermatology, UC Davis School of Medicine,
Suite 1630, 2921 Stockton Blvd, Sacramento, CA 95817, USA
- Department of Ophthalmology,
Sacramento, CA, USA
- Institute for Regenerative Cures, UC Davis School of Medicine,
Suite 1630, 2921 Stockton Blvd, Sacramento, CA 95817, USA
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182
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Chueh SC, Lin SJ, Chen CC, Lei M, Wang LM, Widelitz R, Hughes MW, Jiang TX, Chuong CM. Therapeutic strategy for hair regeneration: hair cycle activation, niche environment modulation, wound-induced follicle neogenesis, and stem cell engineering. Expert Opin Biol Ther 2013; 13:377-91. [PMID: 23289545 PMCID: PMC3706200 DOI: 10.1517/14712598.2013.739601] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION There are major new advancements in the fields of stem cell biology, developmental biology, regenerative hair cycling, and tissue engineering. The time is ripe to integrate, translate, and apply these findings to tissue engineering and regenerative medicine. Readers will learn about new progress in cellular and molecular aspects of hair follicle development, regeneration, and potential therapeutic opportunities these advances may offer. AREAS COVERED Here, we use hair follicle formation to illustrate this progress and to identify targets for potential strategies in therapeutics. Hair regeneration is discussed in four different categories: i) Intra-follicle regeneration (or renewal) is the basic production of hair fibers from hair stem cells and dermal papillae in existing follicles. ii) Chimeric follicles via epithelial-mesenchymal recombination to identify stem cells and signaling centers. iii) Extra-follicular factors including local dermal and systemic factors can modulate the regenerative behavior of hair follicles, and may be relatively easy therapeutic targets. iv) Follicular neogenesis means the de novo formation of new follicles. In addition, scientists are working to engineer hair follicles, which require hair-forming competent epidermal cells and hair-inducing dermal cells. EXPERT OPINION Ideally self-organizing processes similar to those occurring during embryonic development should be elicited with some help from biomaterials.
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183
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Abstract
For tumours to develop, mutations must disrupt tissue homeostasis in favour of deregulated proliferation. Genetic lineage tracing has uncovered the behaviour of proliferating cells that underpins the maintenance of epithelial tissues and the barriers that are broken in neoplastic transformation. In this Review, we focus on new insights revealed by quantifying the behaviour of normal, preneoplastic and tumour cells in epithelia in transgenic mice and consider their potential importance in humans.
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184
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Castilho RM, Squarize CH, Gutkind JS. Exploiting PI3K/mTOR signaling to accelerate epithelial wound healing. Oral Dis 2013; 19:551-8. [PMID: 23379329 DOI: 10.1111/odi.12070] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 12/28/2012] [Accepted: 12/29/2012] [Indexed: 11/29/2022]
Abstract
The molecular circuitries controlling the process of skin wound healing have gained new significant insights in recent years. This knowledge is built on landmark studies on skin embryogenesis, maturation, and differentiation. Furthermore, the identification, characterization, and elucidation of the biological roles of adult skin epithelial stem cells and their influence in tissue homeostasis have provided the foundation for the overall understanding of the process of skin wound healing and tissue repair. Among numerous signaling pathways associated with epithelial functions, the PI3K/Akt/mTOR signaling route has gained substantial attention with the generation of animal models capable of dissecting individual components of the pathway, thereby providing a novel insight into the molecular framework underlying skin homeostasis and tissue regeneration. In this review, we focus on recent findings regarding the mechanisms involved in wound healing associated with the upregulation of the activity of the PI3K/Akt/mTOR circuitry. This review highlights critical findings on the molecular mechanisms controlling the activation of mTOR, a downstream component of the PI3K-PTEN pathway, which is directly involved in epithelial migration and proliferation. We discuss how this emerging information can be exploited for the development of novel pharmacological intervention strategies to accelerate the healing of critical size wounds.
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Affiliation(s)
- R M Castilho
- Laboratory of Epithelial Biology, Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.
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185
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Tracing the cellular origin of cancer. Nat Cell Biol 2013; 15:126-34. [DOI: 10.1038/ncb2657] [Citation(s) in RCA: 205] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 11/20/2012] [Indexed: 12/13/2022]
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186
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Boulter E, Estrach S, Errante A, Pons C, Cailleteau L, Tissot F, Meneguzzi G, Féral CC. CD98hc (SLC3A2) regulation of skin homeostasis wanes with age. ACTA ACUST UNITED AC 2013; 210:173-90. [PMID: 23296466 PMCID: PMC3549711 DOI: 10.1084/jem.20121651] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Loss of CD98hc expression in young adult skin induces changes similar to those associated with aging, including improper skin homeostasis and epidermal wound healing. Skin aging is linked to reduced epidermal proliferation and general extracellular matrix atrophy. This involves factors such as the cell adhesion receptors integrins and amino acid transporters. CD98hc (SLC3A2), a heterodimeric amino acid transporter, modulates integrin signaling in vitro. We unravel CD98hc functions in vivo in skin. We report that CD98hc invalidation has no appreciable effect on cell adhesion, clearly showing that CD98hc disruption phenocopies neither CD98hc knockdown in cultured keratinocytes nor epidermal β1 integrin loss in vivo. Instead, we show that CD98hc deletion in murine epidermis results in improper skin homeostasis and epidermal wound healing. These defects resemble aged skin alterations and correlate with reduction of CD98hc expression observed in elderly mice. We also demonstrate that CD98hc absence in vivo induces defects as early as integrin-dependent Src activation. We decipher the molecular mechanisms involved in vivo by revealing a crucial role of the CD98hc/integrins/Rho guanine nucleotide exchange factor (GEF) leukemia-associated RhoGEF (LARG)/RhoA pathway in skin homeostasis. Finally, we demonstrate that the deregulation of RhoA activation in the absence of CD98hc is also a result of impaired CD98hc-dependent amino acid transports.
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Affiliation(s)
- Etienne Boulter
- Institute for Research on Cancer and Aging, Nice, AVENIR Team, University of Nice Sophia-Antipolis, Institut National de la Santé et de la Recherche Médicale U1081, Centre National de la Recherche Scientifique UMR 7284, Centre Antoine Lacassagne, Nice 06107, France
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187
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Mistriotis P, Andreadis ST. Hair follicle: a novel source of multipotent stem cells for tissue engineering and regenerative medicine. TISSUE ENGINEERING PART B-REVIEWS 2013; 19:265-78. [PMID: 23157470 DOI: 10.1089/ten.teb.2012.0422] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The adult body harbors powerful reservoirs of stem cells that enable tissue regeneration under homeostatic conditions or in response to disease or injury. The hair follicle (HF) is a readily accessible mini organ within the skin and contains stem cells from diverse developmental origins that were shown to have surprisingly broad differentiation potential. In this review, we discuss the biology of the HF with particular emphasis on the various stem cell populations residing within the tissue. We summarize the existing knowledge on putative HF stem cell markers, the differentiation potential, and technologies to isolate and expand distinct stem cell populations. We also discuss the potential of HF stem cells for drug and gene delivery, tissue engineering, and regenerative medicine. We propose that the abundance of stem cells with broad differentiation potential and the ease of accessibility makes the HF an ideal source of stem cells for gene and cell therapies.
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Affiliation(s)
- Panagiotis Mistriotis
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York 14260-4200, USA
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188
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Lee B, Dai X. Transcriptional control of epidermal stem cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 786:157-73. [PMID: 23696356 DOI: 10.1007/978-94-007-6621-1_9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Transcriptional regulation is fundamentally important for the progression of tissue stem cells through different stages of development and differentiation. Mammalian skin epidermis is an excellent model system to study such regulatory mechanisms due to its easy accessibility, stereotypic spatial arrangement, and availability of well-established cell type/lineage differentiation markers. Moreover, epidermis is one of the few mammalian tissues the stem cells of which can be maintained and propagated in culture to generate mature cell types and a functional tissue (reviewed in [1]), offering in vitro and ex vivo platforms to probe deep into the underlying cell and molecular mechanisms of biological functions.
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Affiliation(s)
- Briana Lee
- Department of Biological Chemistry, School of Medicine, University of California, D250 Med Sci I, Irvine 92697-1700, CA, USA
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189
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Sada A, Tumbar T. New insights into mechanisms of stem cell daughter fate determination in regenerative tissues. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 300:1-50. [PMID: 23273858 DOI: 10.1016/b978-0-12-405210-9.00001-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Stem cells can self-renew and differentiate over extended periods of time. Understanding how stem cells acquire their fates is a central question in stem cell biology. Early work in Drosophila germ line and neuroblast showed that fate choice is achieved by strict asymmetric divisions that can generate each time one stem and one differentiated cell. More recent work suggests that during homeostasis, some stem cells can divide symmetrically to generate two differentiated cells or two identical stem cells to compensate for stem cell loss that occurred by direct differentiation or apoptosis. The interplay of all these factors ensures constant tissue regeneration and the maintenance of stem cell pool size. This interplay can be modeled as a population-deterministic dynamics that, at least in some systems, may be described as stochastic behavior. Here, we overview recent progress made on the characterization of stem cell dynamics in regenerative tissues.
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Affiliation(s)
- Aiko Sada
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, USA
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190
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Isolation and cultivation of human scalp interfollicular epidermal stem cells. Methods Mol Biol 2013; 989:11-9. [PMID: 23483383 DOI: 10.1007/978-1-62703-330-5_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Skin regeneration is intricately controlled by epidermal stem cells. In human skin, the long-lived, slow-cycling, and highly proliferative stem cells are located in the basal layer of the interfollicular epidermis (IFE). The ability to isolate and culture human IFE stem cells (IFESCs) offers fascinating therapeutic potential for skin diseases as well as epithelial tissue engineering. Here we describe a straightforward strategy for generation of β1 integrin(+)/CD24(-) IFESCs from scalp with defined, serum-free, feeder-free medium and collagen I-coated culture plates. The use of defined media throughout isolation and cultivation allows for detailed investigation of the molecular events involved in ESC self-renewal and differentiation as well as provides a safe source for clinical use.
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191
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192
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Jadhav SS, Sharma N, Meeks CJ, Mordwinkin NM, Espinoza TB, Roda NR, DiZerega GS, Hill CK, Louie SG, Rodgers KE. Effects of combined radiation and burn injury on the renin-angiotensin system. Wound Repair Regen 2012; 21:131-40. [PMID: 23231670 DOI: 10.1111/j.1524-475x.2012.00867.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 09/27/2012] [Indexed: 01/13/2023]
Abstract
The renin-angiotensin system (RAS) plays an important role in wound repair; however, little is known pertaining to RAS expression in response to thermal injury and the combination of radiation plus burn injury (CRBI). The purpose of this study was to test the hypothesis that thermal injury modifies expression of RAS components and CRBI delayed this up-regulation of RAS. Skin from uninjured mice was compared with mice receiving local thermal injury or CRBI (injury site). Skin was analyzed for gene and protein expression of RAS components. There was an initial increase in the expression of various components of RAS following thermal injury. However, in the higher CRBI group there is an initial decrease in AT(1b) (vasoconstriction, pro-proliferative), AT(2) (vasodilation, differentiation), and Mas (vasodilation, anti-inflammatory) gene expression. This corresponded with a delay and decrease in AT(1) , AT(2) , and MAS protein expression in fibroblasts and keratinocytes. The reduction in RAS receptor positive fibroblasts and keratinocytes correlated with a reduction in collagen deposition and keratinocyte infiltration into the wounded area resulting in a delay of reepithelialization following CRBI. These data support the hypothesis that delayed wound healing observed in subjects following radiation exposure may be in part due to decreased expression of RAS.
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Affiliation(s)
- Sachin S Jadhav
- School of Pharmacy, University of Southern California, Los Angeles, California 90033, USA
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193
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Rittié L, Sachs DL, Orringer JS, Voorhees JJ, Fisher GJ. Eccrine sweat glands are major contributors to reepithelialization of human wounds. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 182:163-71. [PMID: 23159944 DOI: 10.1016/j.ajpath.2012.09.019] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/05/2012] [Accepted: 09/24/2012] [Indexed: 10/27/2022]
Abstract
Eccrine sweat glands are skin-associated epithelial structures (appendages) that are unique to some primates including humans and are absent in the skin of most laboratory animals including rodents, rabbits, and pigs. On the basis of the known importance of other skin appendages (hair follicles, apocrine glands, and sebaceous glands) for wound repair in model animals, the present study was designed to assess the role of eccrine glands in the repair of wounded human skin. Partial-thickness wounds were generated on healthy human forearms, and epidermal repair was studied in skin biopsy samples obtained at precise times during the first week after wounding. Wound reepithelialization was assessed using immunohistochemistry and computer-assisted 3-dimensional reconstruction of in vivo wounded skin samples. Our data demonstrate a key role for eccrine sweat glands in reconstituting the epidermis after wounding in humans. More specifically, (i) eccrine sweat glands generate keratinocyte outgrowths that ultimately form new epidermis; (ii) eccrine sweat glands are the most abundant appendages in human skin, outnumbering hair follicles by a factor close to 3; and (iii) the rate of expansion of keratinocyte outgrowths from eccrine sweat glands parallels the rate of reepithelialization. This novel appreciation of the unique importance of eccrine sweat glands for epidermal repair may be exploited to improve our approaches to understanding and treating human wounds.
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Affiliation(s)
- Laure Rittié
- Department of Dermatology, University of Michigan, Ann Arbor, Michigan 48109, USA.
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194
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Mascré G, Dekoninck S, Drogat B, Youssef KK, Broheé S, Sotiropoulou PA, Simons BD, Blanpain C. Distinct contribution of stem and progenitor cells to epidermal maintenance. Nature 2012; 489:257-62. [PMID: 22940863 DOI: 10.1038/nature11393] [Citation(s) in RCA: 404] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 07/03/2012] [Indexed: 02/07/2023]
Abstract
The skin interfollicular epidermis (IFE) is the first barrier against the external environment and its maintenance is critical for survival. Two seemingly opposite theories have been proposed to explain IFE homeostasis. One posits that IFE is maintained by long-lived slow-cycling stem cells that give rise to transit-amplifying cell progeny, whereas the other suggests that homeostasis is achieved by a single committed progenitor population that balances stochastic fate. Here we probe the cellular heterogeneity within the IFE using two different inducible Cre recombinase–oestrogen receptor constructs targeting IFE progenitors in mice. Quantitative analysis of clonal fate data and proliferation dynamics demonstrate the existence of two distinct proliferative cell compartments arranged in a hierarchy involving slow-cycling stem cells and committed progenitor cells. After wounding, only stem cells contribute substantially to the repair and long-term regeneration of the tissue, whereas committed progenitor cells make a limited contribution.
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Affiliation(s)
- Guilhem Mascré
- Université Libre de Bruxelles, IRIBHM, Brussels B-1070, Belgium
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195
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Seifert K, Büttner A, Rigol S, Eilert N, Wandel E, Giannis A. Potent small molecule Hedgehog agonists induce VEGF expression in vitro. Bioorg Med Chem 2012; 20:6465-81. [DOI: 10.1016/j.bmc.2012.08.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 08/17/2012] [Accepted: 08/20/2012] [Indexed: 12/21/2022]
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196
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Jiménez F, Garde C, Poblet E, Jimeno B, Ortiz J, Martínez ML, Gutiérrez-Rivera A, Pérez-López V, Etxaniz U, Naveda C, Higuera JL, Egüés N, Escario E, Izeta A. A pilot clinical study of hair grafting in chronic leg ulcers. Wound Repair Regen 2012; 20:806-14. [DOI: 10.1111/j.1524-475x.2012.00846.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 07/19/2012] [Indexed: 01/09/2023]
Affiliation(s)
| | - Carmen Garde
- Outpatient Care Unit; Hospital Universitario Donostia; San Sebastian; Spain
| | - Enrique Poblet
- Department of Pathology; Hospital General Universitario Reina Sofía and Universidad de Murcia; Murcia; Spain
| | - Begoña Jimeno
- Outpatient Care Unit; Hospital Universitario Donostia; San Sebastian; Spain
| | - Jesús Ortiz
- Outpatient Care Unit; Hospital Universitario Donostia; San Sebastian; Spain
| | - María L. Martínez
- Department of Dermatology; Hospital General Universitario de Albacete; Albacete; Spain
| | | | | | - Usue Etxaniz
- Department of Bioengineering; Instituto Biodonostia; San Sebastian; Spain
| | - Corina Naveda
- Outpatient Care Unit; Hospital Universitario Donostia; San Sebastian; Spain
| | - José L. Higuera
- Department of Vascular Surgery; Hospital Universitario Donostia; San Sebastian; Spain
| | - Nerea Egüés
- Research Unit; Instituto Biodonostia; Hospital Universitario Donostia; San Sebastian; Spain
| | - Eduardo Escario
- Department of Dermatology; Hospital General Universitario de Albacete; Albacete; Spain
| | - Ander Izeta
- Department of Bioengineering; Instituto Biodonostia; San Sebastian; Spain
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197
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Butler C, Birchall M, Giangreco A. Interventional and intrinsic airway homeostasis and repair. Physiology (Bethesda) 2012; 27:140-7. [PMID: 22689789 DOI: 10.1152/physiol.00001.2012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Human airways are a paragon of intrinsic engineering. They experience 7,000-10,000 liters of airflow/day, have a 70-m(2) surface area, and undergo complete renewal every 100-400 days. Despite this, airways are susceptible to aging, injury, and diseases that are major causes of mortality. Current airway regeneration research is focused both on understanding the cells and strategies responsible for maintaining intrinsic tissue homeostasis as well as on establishing clinical interventions for improving repair.
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Affiliation(s)
- Colin Butler
- Centre for Respiratory Research, Department of Medicine, University College London, Rayne Institute, London, United Kingdom
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198
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Li L, Gu W, Du J, Reid B, Deng X, Liu Z, Zong Z, Wang H, Yao B, Yang C, Yan J, Zeng L, Chalmers L, Zhao M, Jiang J. Electric fields guide migration of epidermal stem cells and promote skin wound healing. Wound Repair Regen 2012; 20:840-51. [PMID: 23082865 DOI: 10.1111/j.1524-475x.2012.00829.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 06/06/2012] [Indexed: 12/25/2022]
Affiliation(s)
- Li Li
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Wei Gu
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Juan Du
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Brian Reid
- Department of Dermatology and Department of Ophthalmology; Institute for Regenerative Cures; UC Davis School of Medicine; Davis; California
| | - Xianjian Deng
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Zhidai Liu
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Zhaowen Zong
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Haiyan Wang
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Bo Yao
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Ce Yang
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Jun Yan
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Ling Zeng
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
| | - Laura Chalmers
- Department of Dermatology and Department of Ophthalmology; Institute for Regenerative Cures; UC Davis School of Medicine; Davis; California
| | - Min Zhao
- Department of Dermatology and Department of Ophthalmology; Institute for Regenerative Cures; UC Davis School of Medicine; Davis; California
| | - Jianxin Jiang
- State Key Laboratory of Trauma; Burns and Combined Injury; Institute of Surgery Research; Daping Hospital; Third Military Medical University; Chongqing; China
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199
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Plikus MV, Gay DL, Treffeisen E, Wang A, Supapannachart RJ, Cotsarelis G. Epithelial stem cells and implications for wound repair. Semin Cell Dev Biol 2012; 23:946-53. [PMID: 23085626 DOI: 10.1016/j.semcdb.2012.10.001] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 10/01/2012] [Indexed: 12/19/2022]
Abstract
Activation of epithelial stem cells and efficient recruitment of their proliferating progeny plays a critical role in cutaneous wound healing. The reepithelialized wound epidermis has a mosaic composition consisting of progeny that can be traced back both to epidermal and several types of hair follicle stem cells. The contribution of hair follicle stem cells to wound epidermis is particularly intriguing as it involves lineage identity change from follicular to epidermal. Studies from our laboratory show that hair follicle-fated bulge stem cells commit only transient amplifying epidermal progeny that participate in the initial wound re-epithelialization, but eventually are outcompeted by other epidermal clones and largely disappear after a few months. Conversely, recently described stem cell populations residing in the isthmus portion of hair follicle contribute long-lasting progeny toward wound epidermis and, arguably, give rise to new interfollicular epidermal stem cells. The role of epithelial stem cells during wound healing is not limited to regenerating stratified epidermis. By studying regenerative response in large cutaneous wounds, our laboratory uncovered that epithelial cells in the center of the wound can acquire greater morphogenetic plasticity and, together with the underlying wound dermis, can engage in an embryonic-like process of hair follicle neogenesis. Future studies should uncover the cellular and signaling basis of this remarkable adult wound regeneration phenomenon.
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Affiliation(s)
- Maksim V Plikus
- Department of Dermatology, Kligman Laboratories, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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200
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Cutaneous wound healing: recruiting developmental pathways for regeneration. Cell Mol Life Sci 2012; 70:2059-81. [PMID: 23052205 PMCID: PMC3663196 DOI: 10.1007/s00018-012-1152-9] [Citation(s) in RCA: 303] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 08/29/2012] [Accepted: 08/30/2012] [Indexed: 12/15/2022]
Abstract
Following a skin injury, the damaged tissue is repaired through the coordinated biological actions that constitute the cutaneous healing response. In mammals, repaired skin is not identical to intact uninjured skin, however, and this disparity may be caused by differences in the mechanisms that regulate postnatal cutaneous wound repair compared to embryonic skin development. Improving our understanding of the molecular pathways that are involved in these processes is essential to generate new therapies for wound healing complications. Here we focus on the roles of several key developmental signaling pathways (Wnt/β-catenin, TGF-β, Hedgehog, Notch) in mammalian cutaneous wound repair, and compare this to their function in skin development. We discuss the varying responses to cutaneous injury across the taxa, ranging from complete regeneration to scar tissue formation. Finally, we outline how research into the role of developmental pathways during skin repair has contributed to current wound therapies, and holds potential for the development of more effective treatments.
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